Nanophotonics 2021; ▪▪▪(▪▪▪): 1–17

Review
Hiroaki Wakiyama, Takuya Kato, Aki Furusawa, Peter L. Choyke and Hisataka Kobayashi*

Near infrared photoimmunotherapy of cancer;
possible clinical applications
https://doi.org/10.1515/nanoph-2021-0119
Received March 20, 2021; accepted April 15, 2021;
published online May 6, 2021

Abstract: Near-infrared photoimmunotherapy (NIR-PIT) isa new cancer treatment that uses an antibody-photoabsorber conjugate (APC) composed of a targeting monoclonal antibody conjugated with a photoactivatablephthalocyanine-derivative dye, IRDye700DX (IR700).
APCs injected into the body can bind to cancer cells where
they are activated by local exposure to NIR light typicallydelivered by a NIR laser. NIR light alters the APC chemical
conformation inducing damage to cancer cell membranes,
resulting in necrotic cell death within minutes of light
exposure. NIR-PIT selectivity kills cancer cells by immunogenic cell death (ICD) with minimal damage to adjacentnormal cells thus, leading to rapid recovery by the patient.
Moreover, since NIR-PIT induces ICD only on cancer cells,
NIR-PIT initiates and activates antitumor host immunitythat could be further enhanced when combined with immune checkpoint inhibition. NIR-PIT induces dramaticchanges in the tumor vascularity causing the superenhanced permeability and retention (SUPR) effect that
dramatically enhances nanodrug delivery to the tumor
bed. Currently, a worldwide Phase 3 study of NIR-PIT forrecurrent or inoperable head and neck cancer patients isunderway. In September 2020, the first APC and accompanying laser system were conditionally approved forclinical use in Japan. In this review, we introduce NIR-PIT
and the SUPR effect and summarize possible applicationsof NIR-PIT in a variety of cancers.

*Corresponding author: Hisataka Kobayashi, Molecular Imaging
Branch, Center for Cancer Research, National Cancer Institute, NIH, 10Center Drive, Bethesda, MD, 20892, USA,
E-mail: kobayash@mail.nih.gov. https://orcid.org/0000-0003-10194112
Hiroaki Wakiyama, Takuya Kato, Aki Furusawa and Peter L. Choyke,
Molecular Imaging Branch, Center for Cancer Research, National
Cancer Institute, NIH, Bethesda, MD, 20892, USA. https://orcid.org/
0000-0001-6388-9888 (H. Wakiyama)Open Access. © 2021 Hiroaki Wakiyama et al., published by De Gruyter.
International License.

Keywords: anti-cancer host immunity; cancer; immunogenic cell death; near-infrared photoimmunotherapy(NIR-PIT); super-enhanced permeability and retention(SUPR) effects.

1 Introduction
Cancer is the second leading cause of death globally [1]. It
is estimated that 19.3 million new cancer cases and almost
10.0 million cancer deaths occurred in 2020. Moreover,cancer incidence and mortality is rapidly rising worldwide, reﬂecting aging and environmental exposures [2].
Three major cancer therapies; surgery, radiation therapy,
and chemotherapy have been the mainstay of cancer
treatment for many decades. Each method can reducecancer burden, however, each treatment also causes severe collateral damage to normal cells including immune
cells and stem cells contributing to disease recurrence anddelayed healing, and resulting in signiﬁcant consequences for quality of life. In the last decade, improved
cancer immunotherapies have dramatically altered thetherapeutic landscape [3]. However, the effectiveness of
immunotherapy depends on altering the careful balanceof effector T cells and immune suppressor cells [4].
Although it can produce spectacular results, the overall
response rate of immunotherapy remains relatively low,
mostly because of the absence of T cell inﬁltration in tumors [5]. Meanwhile, immunotherapy-related side effects,
termed immune-related adverse events (irAEs), have been
widely reported and often mimic autoimmune disease. It
has been reported that irAEs were observed in up to 90% of
patients treated with an anti-cytotoxic T-lymphocyte
antigen 4 (CTLA-4) drug and 70% of those treated with aprogrammed death-1 (PD-1)/PD-ligand 1 (PD-L1) inhibitor,
two common checkpoint inhibitors [6]. Thus, despite advances, no cancer treatment is capable of selectively
killing cancer cells while activating the local host immune
response. Near-infrared photoimmunotherapy (NIR-PIT)
is proposed as a method to overcome these challenges.
In this review, we first provide an overview of NIR-PIT.
Then, we describe how NIR-PIT can enhance nanodrug
This work is licensed under the Creative Commons Attribution 4.0

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H. Wakiyama et al.: Near infrared photoimmunotherapy

delivery based on the super-enhanced permeability andretention (SUPR) effect. Finally, we discuss possible clinical applications of NIR-PIT and SUPR to cancers arising invarious organs.

2 NIR-PITNIR-PIT is a newly developed cancer treatment that employs
an antibody conjugated with the NIR light-absorbing silicon
phthalocyanine dye, IRDye700DX (IR700) [7, 8]. This antibody-photo-absorber conjugate (APC) is injected intravenously where it binds to speciﬁc cancer cells expressing theappropriate antigen on the cell membrane. NIR light(∼690 nm) is then directed to the tumor site activating the
APC to induce cell killing [7, 9–11]. Recently the mechanismof cytotoxicity of NIR-PIT has been explained [12]. Immediately after NIR light exposure, axial ligands of the IR700
molecule, which are responsible for its hydrophilicity, aredissociated from the main molecule causing the APC tochange from a highly hydrophilic to a highly hydrophobic
compound (Figure 1A). This change in chemical propertiesof the APC promotes aggregation leading to damage andrupture of the cellular membrane. The cell membrane isprogressively weakened, microperforations form and ultimately blebbing and bursting occurs, resulting in necrotic
cell death (Figure 1B). Damage to the cellular membrane
during NIR-PIT can be observed with such techniques as
three-dimensional low-coherent quantitative phase microscopy or dual-view inverted selective plane illumination
microscopy [13]. Movies of cells undergoing cell death during NIR-PIT reveal a rapid swelling of the cell, blebbing, andrupture with release of the intracellular contents into theextracellular space. This mechanism of cell death clearly
distinguishes NIR-PIT from conventional photodynamic
therapy (PDT), which relies on the production of reactive
oxygen species to cause non selective damage to adjacentnormal tissue.
In theory, NIR-PIT is most suited to treating superficial
tumors because NIR light can penetrate only approximately 2 cm from the tissue surface [14]. In special circumstances, such as treating tumors in the lung andpleural cavity, NIR light can be transmitted much further

Figure 1: The mechanisms of cell death caused by NIR-PIT.
(A) Structural change of IR700. Upon NIR light exposure, axial ligands are released from the IR700 molecule. Adapted from Ref. [8]. (B) Schemeof the cell killing mechanism induced by NIR-PIT. An antibody–IR700–antigen complex is formed on the antigen on the cell membrane. The
conformational change of conjugate produces physical stress in the cell membrane, resulting in the weakening and rupture of the cell
membrane. The water outside of the cell is ﬂown into the cell, leading cell death. Adapted from Ref. [8].

H. Wakiyama et al.: Near infrared photoimmunotherapy

through the air in the lungs [15–18]. However, in more solid
tissues NIR light is rapidly attenuated and thus, the lightsource must be placed into or nearby tumors [19]. This canbe accomplished by using ﬂexible, cylindrical, ﬁber optic,
interstitial light diffusers that are inserted into the treatment site. Using interstitial light diffusers practically any
tumor site is amenable to NIR-PIT whether inserted via
needle, catheter or endoscope [20, 21]. Furthermore,
implanted wireless NIR light emitting diode (LED) sources
can be used to generate light repeatedly in a remote tumor
site [22]. Since the IR700 is both a therapeutic and a diagnostic, ﬂuorescence imaging can be used to detect sites oftumor to which the APC is bound and direct therapeutic
doses of light to those ﬂuorescing regions. As the light
photobleaches the IR700, there is a decrease in ﬂuorescence reaching a minimum plateau after the dye iscompletely photobleached. It is reported that the therapeutic effect correlates with the photo bleaching extent[12]. A commercially available camera, originally designed
to image indocyanine green, which typically operates atwavelengths of 830 nm, can be repurposed to detect the
low level ﬂuorescence arising from IR700 during NIR-PIT
because of the high intensity of the excitation light and theemission spectrum of IR700 which extends beyond
830 nm. This enables NIR-PIT to be monitored in real timeat wavelengths far from the intense laser excitation light at
690 nm [23].
Unlike most cancer therapies which produce apoptotic
cell death, NIR-PIT is unique in causing “immunogenic cell
death (ICD)” [24, 25]. ICD is a type of cell death in which theadaptive immune system responds to the onslaught of cellassociated antigens released from damaged cancer cells[26, 27]. Apoptotic cell death does not activate the adaptive
immune system [28]. ICD is initiated by the release of
danger signals, such as calreticulin (CRT), adenosine
triphosphate (ATP), high-mobility group box 1 (HMGB1),
heat shock protein (Hsp) 70, and Hsp 90 [29, 30]. These
danger signals activate immature dendritic cells (DCs) andstimulate the presentation of tumor-antigens to T cells.
Cancer cells treated by NIR-PIT release such death signals
as CRT, ATP, and HMGB1. Moreover, the activated DCs
engulf cancer-speciﬁc antigens released from the ruptured
tumor cells thereby converting into mature DCs, which canprime and educate naive T cells to become cancer-speciﬁc
CD8+ T effector cells [24, 31]. NIR-PIT has been shown toconvert some non- or low-immunogenic tumors into
immunogenic tumors by utilizing innate immunity torecognize newly released cancer-speciﬁc antigens. It istherefore, not surprising that NIR-PIT in combination withimmune activation therapies (e.g. immune checkpoint inhibitors) has shown an additive effect and even abscopal

3

effects can be observed in mouse models with intact immune systems [31–34].
Currently, a global Phase 3 clinical trial using anantibody against epidermal growth factor receptor (EGFR)
conjugated to IR700 molecule (Cetuximab-IR700) is being
tested in patients with recurrent head and neck cancers[35]. NIR-PIT has been given fast-track recognition by the
US Food and Drug Administration (FDA). Moreover, theﬁrst EGFR targeted NIR-PIT drug (ASP-1929; Akalux™,
Rakten Medical Inc.) and a diode laser system (BioBlade™,
Rakten Medical Inc.) was conditionally approved andregistered for clinical use by the Pharmaceuticals andMedical Devices Agency in Japan in September 2020.

3 SUPR effect
3.1 Nanoparticle carriers and EPR effectChemotherapy has been a mainstay in the treatment ofadvanced cancer, especially in the late stages. Chemotherapeutic drugs can kill cancer cells effectively but also
damage normal cells causing side effects, such as bonemarrow suppression, mucositis, neurotoxicity, nausea,
vomiting, and hair loss [36, 37]. Since the molecular weightof conventional chemotherapeutic drugs is typically low(<1000 Da), these drugs are delivered everywhere in thebody, and therefore, side effects can involve numerous bodysystems. The serum half-life of conventional chemotherapeutic drugs in blood is short and the off-target accumulation of them in multiple healthy organs is signiﬁcant, andthese two factors result in often severe side effects [38].
Because of rapid progress in nanotechnology, nanoparticle
carriers (NCs) have been developed in the last few decades.
These typically measure 50–200 nm in diameter andtherefore, do not enter most tumors in large amounts. NCs
have the advantage of having large payloads of drug.
However, typically leakage into the tumor parenchyma by
NCs is very limited because of their prolonged circulation
time, NCs accumulate in tumors based on what is known as
the enhanced permeability and retention (EPR) effect, which
was ﬁrst reported by Matsumura and Maeda in 1986 and has
been the basis for developing NCs for tumor-targeted drugdelivery ever since [39, 40]. However, the EPR effect isusually subtle and the effect is not large. It arises from abnormalities in the inherent permeability of tumor bloodvessels and absence of lymphatic drainage in tumors.
Nanomaterials with sizes up to several hundred nanometersslowly extravasate from tumor blood vessels and areretained in tumor beds, leading to a relatively effective andselective accumulation of NCs in solid tumors. However, the4

H. Wakiyama et al.: Near infrared photoimmunotherapy

EPR effect is misleadingly prominent in small animal
xenograft models and frustratingly minimal in most humantumors [41]. While many preclinical studies showed that NCs
were effective for tumor treatment, most have not beensuccessful when tested in human clinical trials [42–44].
Therefore, most of recent studies have tended to investigate
approaches to extend the conventional EPR-based targetingwith NCs, which is known as “passive targeting”.

3.2 Strategies for improving of delivering
nanodrugs into tumors
Unlike passive targeting, active targeting, using targeting ligands such as antibodies, fragments of antibodies and peptides, can be a complementary strategy
to enhance nanomedicine tumor accumulation andretention. For example, 90Y-ibritumomab tiuxetan(Zevalin®), 131I-tositumomab (Bexxar®) and denileukin
diftitox (Ontak®) have been approved for clinical use by
the FDA [45, 46]. Triggered drug release can be anothercomplementary strategy. Drug delivery systems madefrom materials that are sensitive to an external stimulus(e.g. pH, temperature, ultrasound, electrical and magnetic ﬁelds, and speciﬁc molecules) are designed torelease the payload drug only when it has reached thetumor and encounters a release stimulus [47–49]. As aresult, triggered drug release can treat tumors selectively and efﬁciently while minimizing nonspeciﬁc
toxicity. Although active targeting and triggered drug
release have obvious appeal as delivery strategies, thesetargeted agents must still enter tumor sites in sufﬁcientconcentrations to be effective. Accordingly, adequatepassive targeting is required before both strategies canbe effective.

3.3 Strategies for improving of the drugdelivery to tumor sites
The efficiency of passive targeting depends on thepermeability of tumor vasculature, interstitial fluid pressure (IFP), and forces exerted by nonfluid components.
Tumor vessels are often enlarged, leaky, and exhibit
bidirectional flow. These factors tend to create unevendelivery of drugs within the tumor [50]. IFP is often morethan 5–10 mmHg within a tumor compared to near zero innormal non tumor tissue decreasing the pressure gradient
between capillaries and the extracellular space and thus,
reducing diffusion of nanoparticles [51]. Extracellularmatrix (ECM) can also be a transport barrier to drugdelivery as it can narrow the vasculature, increase thediffusion distance from vessels to the tumor cells; entrap
drugs and create a steric obstruction to diffusion of
nanoparticles [51]. Tumor cells and the ECM create a solid
stress within tumors [52]. The EPR effect can be improvedby altering any of the above conditions. There are threemain strategies to modify the tumor environment: (i) increase tumor blood ﬂow, (ii) normalize the vessels themselves, and (iii) reduce transcapillary resistance [53].

3.4 SUPR effect
NIR-PIT kills cancer cells without destroying surrounding normal cells (e.g. vascular endothelial cells). When
APCs arrive at a tumor they leak from the blood vessels
and bind to the tumor. By virtue of their proximity to thevessel, the APCs tend to bind to the first cells theyencounter, namely perivascular cells. Therefore, the firstcells to be killed by NIR-PIT are perivascular tumor cells.
The immediate death of perivascular cancer cells createsa potential space between the vessel wall and theremaining tumor which allows nanodrugs to enter thetreated tumor beds at dramatically increased concentrations than could be achieved with EPR alone. The
drastic increase in permeability and retention in tumor
beds following NIR-PIT has been termed the “superenhanced permeability and retention” (SUPR) effect(Figure 2A) [44, 54, 55]. The SUPR effect allows muchhigher concentrations of nanodrugs into the tumor, since
the initial binding site barrier has been eliminated. Thus,
nanodrugs not only accumulate in higher concentrations
but can also inﬁltrate deeper into tumors following
NIR-PIT. After NIR-PIT, SUPR effects are always observed
permitting the accumulation of many types of nanodrugsof various sizes up to several hundred nanometers indiameter (e.g., monoclonal antibody targeting tumor,
nontargeted PEG-coated quantum dots, iron oxide
nanoparticles, and dendrimer-based nanosized contrast
agents) [54, 56]. Up to 24-fold greater accumulation ofuntargeted nanoparticles has been measured after
NIR-PIT compared to untreated control tumors in which
only the conventional EPR effect is present (Figure 2B)[54]. When NIR-PIT was combined with clinicallyapproved nanodrugs such as liposomal daunorubicin(DaunoXome®) or albumin-bound paclitaxel (Abraxane®), therapeutic effects were signiﬁcantly enhanced
compared to single therapy of either NIR-PIT or nanodrugs [54, 57]. Therefore, the combination of NIR-PIT and
nanodrugs could be a promising strategy for increasing
the effectiveness of either monotherapy alone.

H. Wakiyama et al.: Near infrared photoimmunotherapy

Figure 2: The mechanisms of SUPR effects induced by NIR-PIT.
(A) Scheme of SUPR effect induced by NIR-PIT. Many of the initial cellkilling occurs in the perivascular layer of tumor cells after NIR-PIT,
leading to form a potential space around the tumor vasculature. It
increases vascular permeability and decreases interstitialpressures. Then, nanodrug delivery to the remaining tumor can beenhanced. Adapted from Ref. [8]. (B) The increases of PEGylated
quantum dot 800 into tumor bed 1 h after NIR-PIT were observed
compared to control tumors (up to 24-fold). Adapted from Ref. [8].

4 NIR-PIT for various cancers
NIR-PIT can be applied with any surface marker of cancer
or stromal cells provided that an antibody exists to bind toit [8, 58, 59]. In this section, we discuss a range of NIR-PIT
applications for various cancers in clinical and preclinicalstudies (Figure 3).

4.1 Head and neck squamous cell carcinoma
Head and neck cancer is the seventh most common cancer
with >931,000 new cases worldwide and is seventh the mostcommon cause of cancer death with >467,000 deaths
worldwide in 2020 [2]. Head and neck squamous cell carcinoma (HNSCCs) is the most common type of head and neckcancer [60]. Risk factors for HNSCCs are exposure totobacco-derived carcinogens, excessive alcohol consumption, and human papillomavirus or Epstein–Barr virus
infection. Approximately 30–40% of HNSCC patients

5present at an early stage are curable with surgery or radiotherapy alone. However, multimodality treatment including
surgery, radiation, chemotherapy, or immunotherapy isoften required for late-stage patients, which constitute morethan 60% of patients [61]. The side effects of these combined
therapies can damage the delicate structures controllingspeech, taste and swallowing leading to debilitating loss ofquality of life [62]. Therefore, developing new therapeutic
methods which treat the cancer effectively while preserving
function is a high priority.
Head and neck cancers are amenable to NIR-PIT
because they are often close to the skin or mucosa. Interstitial light fibers can be inserted into deeper tumors.
Because head and neck cancers can invade critical
vascular structures, care must be taken when treating headand neck cancers with NIR-PIT.
The most clinical experience exists for head and neck
NIR-PIT. EGFR is overexpressed in up to 90% of HNSCCs[63]. Cetuximab, which is a chimeric IgG1 monoclonal
antibody and a competitive inhibitor of EGFR ligand
binding, was approved by the FDA in 2006. CetuximabIR700 was the ﬁrst agent clinically introduced for NIR-PIT.
A Phase 1/2 clinical trial of NIR-PIT using cetuximab-IR700
in patients with recurrent HNSCC concluded in 2017 andshowed that cetuximab-IR700 NIR-PIT is more effective
than current second- and third-line therapies for recurrent
HNSCCs [64]. These results prompted the FDA to assign afast track designation for cetuximab-IR700 in 2018. In
September 2020, cetuximab-IR700 received conditional
approval from the Japanese Ministry of Health, Labor, andWelfare as a treatment for HNSCC patients. A global phase
3 trial in recurrent HNSCC is currently underway [35]. It is
anticipated that NIR-PIT may be used earlier in the disease,including on premalignant lesions in the mouth such as
leukoplakia which also express EGFR.
CD44, a cancer stem cell (CSC) marker, is also
expressed on HNSCC. Its presence is a negative prognostic
indicator and is associated with tumor progression,
metastasis and poor prognosis [65]. In mouse homograftmodels, CD44 targeted NIR-PIT suppressed tumor growthand prolonged survival [32]. Moreover, CD44 targeted
NIR-PIT with PD-1 blockade therapy was more effective
than single therapies in mouse homograft models
including a minimally immunogenic tumor [31, 34].

4.2 Glioblastoma multiforme
Glioblastoma multiforme (GBM) is among the mostaggressive tumors in adults and carries a dismal 5 year
prognosis of only 5.5% [66, 67]. In the United States, an6

H. Wakiyama et al.: Near infrared photoimmunotherapy

Figure 3: Various cancers and promisingtargets for NIR-PIT.

estimated 11,833 patients are diagnosed with GBM per year[68]. The current standard of care for patients younger thanage 70 years with newly diagnosed GBM is maximal safe
surgical resection, followed by radiation therapy andconcomitant temozolomide (TMZ) followed by adjuvant
TMZ [66]. For elderly patients performance status can affecttreatment decisions and is adjusted according to the abilityof the patient to tolerate the intense combination therapy[69]. Even though GBM is well known to extend beyond thevisible borders seen on brain MRI, studies of recurrence
patterns of GBM after surgery, radiotherapy, and chemotherapy have shown that ∼80–90% of recurrences arewithin the original treatment ﬁeld [70–73], suggesting the
efﬁcacy of current therapeutic methods is insufﬁcient.
NIR-PIT could be a useful adjuvant to surgery to selectively
kill the unresected tumor cells that invade around surgicalcavity.
Although NIR light can transmit through the skull it isuncertain whether it is of sufficient intensity to treat GBMs.
More likely NIR-PIT will be used with thin fibro optic diffusers through inserted small catheter or as an adjuvant tosurgery after the skull is opened. Direct light application to
the surgical field could be useful in sterilizing tumor margins. It is possible that wireless LEDs could also be inserted
in the surgical cavity to supply light as needed in case ofrecurrent disease [22].
Several studies have shown EGFR gene amplificationin ∼40% of all GBMs [74–76]. Burley et al. reported that
EGFR targeted NIR-PIT showed effectiveness in xenograftmodels of GBM [77]. Therefore, the most likely ﬁrst APC to
be used in GBM will be cetuximab-IR700.
Therapeutic resistance may also arise from CSCs within
GBMs [78, 79]. The neural stem cell marker CD133 has been
the CSC marker most associated with GBM and identiﬁes
cells with higher rates of self renewal and proliferation andincreased differentiation ability [80, 81]. In orthotopic
xenograft models, anti-CD133-IR700 conjugates accumulated in brain tumors, suggesting anti-CD133-IR700 canpass through the blood brain barrier. Moreover, CD133
targeted NIR-PIT was highly efﬁcient in both the subcutaneous and orthotopic models [11]. Therefore, EGFR or CSC
targeted NIR-PIT is a potential therapy for GBMs.

4.3 Esophageal cancer
Esophageal carcinoma is the 11th most common cancer
with >604,000 cases worldwide and is the sixth mostcommon cause of cancer death with >544,000 deaths
worldwide in 2020 [2]. The two major subtypes of esophageal cancer are esophageal squamous cell carcinoma(ESCC) and esophageal adenocarcinoma (EAC). ESCC represents 90% of all cases of esophageal cancer globally andis dominant in East Asia, East Africa, and South America.
EAC is more common in developed countries than indeveloping countries [82]. Most patients with esophageal
cancer need multimodality treatment, including chemotherapy, chemoradiotherapy, and/or surgical resection.
Recurrences are particularly difﬁcult to treat.

H. Wakiyama et al.: Near infrared photoimmunotherapy

NIR-PIT would most likely be applied in conjunction
with upper gastrointestinal (GI) endoscopy. The operator
could identify the tumor location and then apply NIR lightto tumors in patients who had previously received the APC.
Naturally, treatment of transmural tumors could lead toesophageal perforations so proper patient selection isneeded.
Between 71 and 91% of ESCCs and 32–64% of EACs
express EGFR and therefore may be potential candidates for
EGFR targeted NIR-PIT [83–87]. Overexpression of humanepidermal growth factor 2 (HER2) has been reported in up to
64% of ESCCs and 32% of EACs, respectively [88–90]. In vitro
studies, EGFR or HER2 targeted NIR-PIT has been shown tobe effective in esophageal carcinoma cell lines [91].
In addition to epithelial growth factor receptors,
many studies have emphasized the importance of cancerassociated fibroblasts (CAFs) in esophageal carcinoma[92, 93]. CAF targeted NIR-PIT inhibited tumor progression in co-culture models of ESCCs and CAFs [94, 95].
Therefore, esophageal cancer could be treated with somecombination of EGFR, HER2, or CAF targeted NIR-PIT. It is
possible in the future that cocktails of APCs could be used
to more completely treat particular cancers.

4.4 Lung cancer
Lung cancer is the second most common cancer with
>2,206,000 new cases worldwide and is the most common
cause of cancer death with >1,796,000 deaths worldwide in2020 [2]. The two major subtypes of lung cancer are nonsmall cell lung cancer (NSCLC) (85% of patients) and small
cell lung cancer (SCLC) (15%) [96].
The lungs are a particularly interesting organ toconsider treating with NIR-PIT. NIR light transmits throughair very well. For lesions near the main bronchi it may bepossible to deliver light via a bronchoscope. For deeper
lesions a bronchoscope or transcutaneous fiber might beused. It may be possible to treat several lesions simultaneously by applying light to normal lung and having it
transmit throughout the lung. Intraoperatively, light could
be directed to pleural surfaces or to the lung parenchyma.
EGFR overexpression has been identified in 40–80% of
NCSLCs [97]. NIR-PIT with panitumumab (another antibody targeting EGFR)-IR700 conjugates inhibited tumor
growth in a transgenic mouse model of spontaneous lungcancer expressing human EGFR [15]. Several monoclonal
antibodies (mAbs) against PD-L1 and PD-1 have demonstrated clinical beneﬁt in patients with NSCLC and arecollectively known as checkpoint inhibitors [98–100].
PD-L1 is over expressed in many cancers, and therefore it is7

a potential target for NIR-PIT. NIR-PIT using avelumab(human antiPD-L1 mAb)-IR700 induced signiﬁcant therapeutic effects in an NSCLC xenograft model [101]. Thus,
PD-L1 targeted NIR-PIT might be useful for NSCLC cancers
with high PD-L1 expression. SCLC has a poor prognosis andit is commonly diagnosed at an advanced, unresectablestage [102]. Delta-like protein 3 (DLL3) is a potential therapeutic target molecule for SCLC [103], but rovalpituzumab
tesirine, which is the ﬁrst antibody drug conjugate (ADC)
targeting DLL3, was terminated on August 2019 because of
failure of both the TAHOE (NCT03061812) and MERU
(NCT03033511) clinical trials. The failure of this ADC is notnecessarily an indictment of the antibody; however,
NIR-PIT targeting DDL3 showed marked antitumor effects[104]. Malignant cells in the pleural ﬂuid or pleural metastases are classiﬁed as M1a and stage IV according to
TNM Classiﬁcation of Malignant Tumors 8th edition (UICC
8th edition) and typically surgical resection is excluded[105]. Therefore, therapies that could treat pleural metastases without damage to the adjacent organs might prolong
survival. In xenograft models, HER2 targeted NIR-PIT led tosigniﬁcant reduction in pleural dissemination by HER2
expressing NSCLC cells [18]. Furthermore, in mouse models
of lung metastasis, HER2 targeted NIR-PIT showed significant reductions in metastasis tumor volume and prolonged survival [16, 17]. These results suggest a potential
new therapy for the local control of lung metastases or
pleural dissemination which could readily be translated toclinical treatments.

4.5 Malignant pleural mesothelioma
Malignant pleural mesothelioma (MPM) is a malignant
tumor that originates from mesothelial cells in the pleuraand peritoneum and has an extremely poor prognosis, witha median survival of 8–14 months [106]. It is often debulked
with extrapleural pneumonectomies but recurrence iscommon.
NIR-PIT could be considered at the time of thedebulking procedure. At that time the mesothelioma would
be exposed and NIR light could be directly applied to thetumor surface. It may also be possible to deliver light to thepleura broncho-scopically in some cases.
Podoplanin (PDPN) is a type I transmembrane glycoprotein that is expressed in lymphatic endothelial cells,
type I alveolar epithelial cells, and podocytes of theglomeruli. PDPN is a specific pathological diagnostic marker
to distinguish lymphatic vessels from blood vessels but it isalso expressed in MPM [107–109]. PDPN targeted NIR-PITin MPM models suppressed tumor progression [110].

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Another MSM marker, mesothelin (MSLN) is a cell surface
glycoprotein that is a target for antibody-based therapies[111, 112]. MSLN targeted NIR-PIT has been shown to beeffective in mouse xenograft models [113]. These ﬁndings
suggest that PDPN and/or MSLN targeted NIR-PIT might be apotential alternative treatment of MPM.

4.6 Breast cancer
Female breast cancer is the most common cancer with
>2,260,000 new cases worldwide and is the fifth mostcommon cause of cancer death with >684,000 deaths
worldwide in 2020 [2]. Breast cancer is classiﬁed into threemajor subtypes based on the presence or absence of molecular markers for two hormone receptors (HR) andHER2. HER2, which is a member of the epidermal growth
factor receptor family, regulates cell proliferation, differentiation, and apoptosis through signal transduction.
Tumors are classiﬁed by their HR and HER2 status: HR+/
HER2− (70% of patients), HR±/HER2+ (15–20%), and“triple-negative” (HR−/HER2−; 10–15%) [114]. Breast
cancer is treated by multimodal therapy. Locoregional
therapies include surgery and radiation therapy. Systemic
therapies include hormone therapy for HR+ patients,
chemotherapy, HER2 targeted therapy for HER2+ patients,
bone-modifying agents, poly (ADP-ribose) polymerase(PARP) inhibitors for BRCA-mutated cancer and immunotherapy [114–117].
NIR-PIT could be used in a variety of ways in breast
cancer. For localized disease it could be a method oftreating the cancer with interstitial fibers. For local recurrences or recurrences in the chest wall a similar strategy
could be used. For lung metastases it might be possible toilluminate the lungs to deliver light.
Trastuzumab, an anti-HER2 mAb has been used as an
NIR-PIT agent in xenograft models of breast cancer [7].
Cells that are unresponsive to HER2 targeted NIR-PIT areoften shown to be HER2 targeted NIR-PIT-responsive after
viral transduction of the HER2-extracellular domain [118].
For triple-negative breast tumors, no targeted therapy iscurrently available. However, EGFR expression has beenreported in 50–89% of cases [119, 120]. Therefore, EGFR
targeted NIR-PIT could be used in some cases of triplenegative breast cancer. In xenograft models with two
different cell lines established from triple-negative breast
cancers, cetuximab-IR700 NIR-PIT suppressed tumor
growth and prolonged survival [121].

4.7 Gastric cancer
Gastric cancer is the sixth most common cancer with
>1,089,000 new cases worldwide and is the fourth mostcommon cause of cancer death with >768,000 deaths
worldwide in 2020 [2]. Helicobacter pylori infection has
been implicated in more than 93% of gastric cancer patients [122]. In the trastuzumab for gastric cancer trial(ToGA trial), HER2 positivity was 22.1% [89]. The FDA
approved trastuzumab (anti-HER2 mAb) in combination
with chemotherapy as a standard treatment for patientswith HER2+ advanced gastric or gastro-esophageal junction cancer in 2010 [123]. In mouse models of peritoneal
carcinomatosis or a ﬂank tumor, HER2 targeted NIR-PIT
showed signiﬁcant reductions in tumor volume [124]. The
combination therapy of HER2 targeted NIR-PIT (using
Trastuzumab-IR700) and conventional chemotherapy of
5-FU rapidly induced signiﬁcant tumor inhibition [125].
Currently, anti-HER2 antibodies recognizing different
epitopes of HER2 have been developed, such as pertuzumab which could also be used for NIR-PIT. NIR-PIT withtrastuzumab-IR700 and pertuzumab-IR700 conjugates
showed stronger antitumor effects than either antibody
conjugate alone [126]. Less than 6% of the normal gastrictissues demonstrated EGFR expression, whereas EGFR
was expressed in 41.8–57.7% of gastric cancers byimmunohistochemistry (IHC) analysis [127–129]. Therefore, EGFR targeted NIR-PIT, perhaps in combination with
HER2 targeted NIR-PIT might be a suitable treatment forsome patients with gastric cancer.

4.8 Colorectal cancer
Colorectal cancer is the third most common cancer with
>1,880,000 new cases worldwide and is the second mostcommon cause of cancer death with >915,000 deaths
worldwide in 2020. The incidence rate of colorectal cancer ishigher in developed countries than in developing countries[2]. With economic growth in developing countries, it isestimated that the incidence of colorectal cancer could increase to 2.5 million new cases by 2035 [130]. Carcinoembryonic antigen (CEA) is preferentially expressed in coloncancer cells compared to normal colon cells [131, 132].
Moreover, overexpression of CEA in tumor tissue is associated with a negative prognostic sign [133, 134]. CEA targeted
NIR-PIT inhibited tumor growth in a CEA-expressing mouse
xenograft model [135, 136].

H. Wakiyama et al.: Near infrared photoimmunotherapy

Another potential target for NIR-PIT in colon cancer isthe glycoprotein A33 antigen (GPA33) which is highly
expressed in over 95% of human colorectal cancers andexhibits limited expression in normal intestinal epithelium[137]. GPA33 targeted NIR-PIT showed signiﬁcant efﬁcacy
in xenograft models [138]. EGFR overexpression has been
observed in 43.9–97% of colorectal cancer patients basedon IHC analysis [139–142]. Some of the anti-EGFR mAbs
including cetuximab and panitumumab have been
approved by FDA as ﬁrst-line treatments of colorectal
cancer [143]. Thus, EGFR targeted NIR-PIT could be utilized
as adjuvant therapy in conjunction with surgery orlaparoscopy.

4.9 Liver cancer
Liver cancer is the eighth most common with >905,000 new
cases worldwide and is the third most common cause ofcancer death with >830,000 deaths worldwide in 2020 [2].
Hepatocellular carcinoma (HCC) is the most common typeof primary hepatic malignancy. HCC is caused by chronicviral hepatitis which results in cirrhosis and tumor formation. Treatments include surgery, radiation, chemotherapy, immunotherapy, and liver transplantation. In
general, mortality rates are high for HCC.
Since HCC is usually found within the liver parenchyma it would have to be approached with catheters or
fiber optic needles. The liver itself is relatively poor at lighttransmission so it is important that the fiber optic needles
would be placed within the tumor itself. In the future it may
be possible to leave in place wireless LEDs to provide lightin the event of recurrence after NIR-PIT.
Glypican-3 (GPC3) is highly expressed in HCC but not
in normal tissue, and therefore, is a target-candidate for
NIR-PIT [144]. GPC3 targeted NIR-PIT inhibited tumor
growth compared to untreated controls in a xenograftmodel of HCC [145]. Moreover, the combination of GPC3
targeted NIR-PIT and nanoparticle albumin-bound paclitaxel enhanced the therapeutic effect compared to either
alone [57]. The post NIR-PIT SUPR effect enabled more drugdelivery to the tumor. Cholangiocarcinoma (CCA) is thesecond most common liver cancer after HCC accounting for∼15% of all primary liver cancers and ∼3% of all gastrointestinal cancers worldwide [146]. It is difﬁcult to deliver NIR
light into the bile duct for CCA from outside the body.
However, newly developed catheter-based devices containing LEDs could be used to deliver light for NIR-PIT
resulting in tumor suppression in xenograft models [147].
Tumor-associated calcium signal transducer 2 (TROP2) isoverexpressed in many epithelial cancers including CCA

9[148] and TROP2 corelates with a poor prognosis in various
cancers [149]. TROP2 targeted NIR-PIT inhibited tumor
growth in CCA xenograft model [150].

4.10 Pancreatic cancer
Pancreatic cancer is the 14th most common cancer with
>495,000 new cases worldwide and the eighth most common cause of cancer death with >466,000 deaths worldwide in 2020 [2]. Pancreatic cancer is aggressive and often
presents late because symptoms are nonspeciﬁc or minimal early in the disease. The pancreatic cancer cell isparticularly aggressive and the tumor recurrence rate afterradical surgical resection is 80% even though surgical
techniques and adjuvant treatments have improved in thelast decades [151].
The pancreas primary is difficult to approach with light.
It is possible, depending on the tumor location in thepancreas, that endoscopic-ultrasound-light delivery could
provide light to the tumor. More realistically, NIR-PIT could
be performed as an adjuvant to open or laparoscopic surgery.
Given the high rate of recurrence it may be especially beneficial to have a wide field of NIR-PIT in pancreatic cancer.
Among the targets potentially suitable for NIR-PIT
targeting is anti-CEA mAb-IR700 which demonstrated agood response in an orthotopic xenograft model [152].
Cadherin-17 (CDH17) is highly expressed on gastrointestinal cancer cells. CDH17 targeted NIR-PIT inhibited tumor
growth in a xenograft model which used a pancreaticcancer cell line [153]. TROP2 is also overexpressed inpancreatic cancer [148]. TROP2 targeted NIR-PIT inhibitedtumor growth in pancreatic cancer xenograft models [150].
Moreover, CEA targeted NIR-PIT following surgery reduced
recurrence by eliminating remaining cancer cells [154, 155].
EGFR expression was observed in 62–69% of pancreaticcancer patients with IHC analysis [156–158]. Thus, somecombination of antibody conjugates engaging CEA, CDH17,
TROP2, and EGFR might be successful in pancreatic cancer.

4.11 Ovarian cancer
Ovarian cancer is the 19th most common cancer with
>313,000 new cases worldwide and the 15th most common
cause of cancer death with >207,000 deaths worldwide in2020 [2]. Since ovarian cancer is a highly metastatic disease,a minority (15%) of patients is diagnosed with localized tumor (stage I) however, when early diagnosis can be madethe 5-year survival is 92%. However, the majority of cases
present late with disseminated intra abdominal disease

10

H. Wakiyama et al.: Near infrared photoimmunotherapy(stages III–IV) with a 5-year survival of 25% [159, 160].
Standard therapy of ovarian cancer is a combination ofchemotherapy and surgery. Cytoreductive surgery is
initially employed to remove all macroscopic disease (R0resection). The success of the R0 resection is a prognostic
indicator [161, 162]. When the disease is considered to be
R1 (<1 cm), all visible disease is removed but viablemicroscopic cancer cells are assumed to remain at thesurgical margin and recurrence is common [160, 163].
Therefore, the development of new therapies for treating
residual disease in the peritoneum after cytoreductive
surgery is needed.
A typical pattern of recurrence is in the peritoneum
where direct light exposure is possible during open orlaparoscopic procedures. Lymph node metastases present
a greater problem and may require direct light exposure
during surgery. While NIR-PIT might not be curative in allcases it could be very useful in killing recurrent peritoneal
disease thus staving off the primary symptom of recurrent
ovarian cancer, malignant ascites.
HER2 targeted NIR-PIT showed significant tumor suppression in subcutaneous tumor models but also indisseminated peritoneal models using HER2 expressing
ovarian cancer cell lines [164]. Galactosyl serum albumin(GSA) binds to beta-D-galactose receptors, which is overexpressed on the surface of many ovarian tumors [165].
GSA targeted NIR-PIT speciﬁcally killed ovarian cancer
cells (SHIN3) in vitro and suppressed tumor growth in aperitoneal disseminated model [166].

4.12 Bladder cancer
Bladder cancer is the 13th most common cancer with>573,000 new cases and is the 14th most common causeof cancer death with >212,000 deaths worldwide in 2020[2]. Evaluation of bladder cancer patients is performed
using cystoscopy with a ﬂexible scope [167]. EGFR and
HER2 were detected in 72.2 and 44.5% of bladder cancers,
respectively [168]. Therefore, these receptors could betargets for NIR-PIT in bladder cancer. EGFR targeted
NIR-PIT caused cell death in human bladder tumor celllines in vitro and inhibited tumor growth in bladder tumor xenograft models [169, 170]. Moreover, combined
EGFR and HER2 targeted NIR-PIT inhibited tumor growthsigniﬁcantly in a xenograft bladder tumor model [171].
CD47, one of the “don’t eat me” signals for macrophages,
is also highly expressed (80%) in bladder cancer tumors,
but is not expressed on normal luminal urothelium [172].
Kiss et al. reported that CD47 targeted NIR-PIT killedhuman bladder tumor cell lines and patient derived

bladder tumor cells in vivo, and suppressed tumor
growth in xenograft models [173].

4.13 Prostate cancer
Prostate cancer is the fourth most common cancer with
>1,414,000 new cases and is the ninth most common causeof cancer death with >375,000 deaths worldwide in 2020[2]. Prostate cancer is treated by surgery, radiation or active
surveillance in the case of low-grade cancers. Because of
the high morbidity of prostate cancer treatments (urinary
incontinence and erectile dysfunction) alternative therapies have been proposed. Focal therapies consist of ablative methods that physically destroy prostate cancers but
also tend to undertreat inﬁltrative disease while damaging
normal prostate tissue.
Prostate cancer NIR-PIT could be relatively straightforward as the prostate is commonly biopsied using
MRI-Ultrasound fusion imaging. Instead of biopsy needles,
fiber optic needles could be introduced into the prostate
enabling the killing of cancer cells while sparing criticalstructures like the urethra, sphincters, and pelvic nerves.
Prostate-specific membrane antigen (PSMA) is overexpressed significantly in prostatic cancer cells and theexpression level of PSMA is associated with the stage andgrade of the prostate cancer but the expression is low innormal tissues [174]. Thus, PSMA is a reasonable target formolecular therapy. PSMA targeted NIR-PIT eliminatedprostate tumor cells signiﬁcantly in vivo and suppressedtumor progression and prolonged survival in xenograftmodels [175]. Moreover, PSMA targeted NIR-PIT using antiPSMA diabody (Db) or anti-PSMA minibody (Mb), which
are small and bivalent antibody fragments of antiPSMA-IgG, showed PSMA+ cell death in vitro and suppressed tumor growth in a xenograft model [176]. A majoradvantage of PSMA targeted NIR-PIT is that suitable patients could be determined using PSMA PET scans prior to
the procedure [177]. This would localize the tumor accurately and allow placement of ﬁber optic catheters.
Following NIR-PIT the same PSMA PET scan could be used
to determine the success of the procedure and whether
additional treatments might be needed.

4.14 Lymphoma
Lymphoma is the ninth most common cancer with
>627,000 new cases worldwide and is the 12th most common cause of cancer death with >283,000 deaths worldwide in 2020 [2]. Traditionally, lymphoma is divided into

H. Wakiyama et al.: Near infrared photoimmunotherapy

Hodgkin’s lymphoma (approx. 13% of all lymphomas) andnon-Hodgkin’s lymphoma [2]. The majority of lymphomas
are B cell origin [178]. B-cell lymphomas often express
B-cell markers, such as CD19 and CD20, which can bind
speciﬁc mAbs [179]. CD20 targeted NIR-PIT using
rituximab-IR700 conjugates showed efﬁcacy in xenograftmodels of B-cell lymphoma [180]. Furthermore, the therapeutic effect of CD20 targeted NIR-PIT was more effective
than that of radioimmunotherapy in a xenograft model ofaggressive B-cell lymphoma [181]. Mycosis fungoides (MF)is a rare cancer however; it is the most common subtype of
cutaneous T-cell lymphoma [182]. It is reported that
MF cells express cutaneous lymphocyte antigen (CLA)[183]. CLA targeted NIR-PIT speciﬁcally killed MF cell line
in vitro [184]. Thus, NIR-PIT could treat the locoregional
lymphomas including skin-based lymphoma which would
be highly amenable to direct NIR light exposure.

4.15 Melanoma
Melanoma is the most aggressive and the lethal form ofskin cancer. Melanoma is treated by multimodal therapies,
such as surgical resection, chemotherapy, PDT, immunotherapy, and targeted therapy using small molecule inhibitors or antibodies [185].
Because early melanoma is usually present on the skinsurface it is relatively amenable to direct NIR light exposure, however, deeper nodal involvement might requireinterstitial placement of catheters/fiber optics in order todelivery light to all facets of the tumor.
CD146 has been identified as a melanoma cell adhesion molecule. CD146 is overexpressed in 70% of primarymelanomas and 90% of lymph node metastases [186]. Wei
et al. reported that CD146 targeted NIR-PIT inhibited tumor
growth in CD146-positive melanoma xenograft model [187].
Thus, CD146 targeted NIR-PIT could be a potential methodof treating melanomas without highly disﬁguring surgery.

4.16 Bone metastases
Bone is the third most common site of metastases in cancer
patients [188]. It has been assumed that NIR-PIT for bonemetastases would have no effect because light cannot
penetrate bone. However, ex vivo experiments showed that
NIR-PIT not only penetrates bone but can kill tumor cells
located behind bone. Moreover, tumor viability was
reduced by NIR-PIT [189]. Hence, in spite of decreasing of

11

light transmittance, NIR-PIT nonetheless is able to treat
cancers within bone.

5 Conclusion
NIR-PIT is a new cancer therapy with broad applications. It
has an immediate effect on the tumor neovasculature which
results in the SUPR effect which enables nanodrugs topenetrate into the treated tumor at far higher concentrations
than are normally possible. It also profoundly activates theimmune system both locally and, in some cases, systemically.
NIR-PIT kills cancers in a highly specific manner and therefore, could be used in a variety of cancers. Each cancer requires one or more specific antibodies that bind the tumor
and can be conjugated with IR700 to become an NIR-PIT
agent. Using cocktails of mAb-IR700 conjugates that are
injected intravenously and various methods of delivering
light, a wide range of tumors could be treated with minimalside effects. Recently, EGFR targeted NIR-PIT was conditionally approved in Japan and a phase 3 clinical trial isongoing. Thus, NIR-PIT has great potential to become awidely applicable cancer therapy in the near future.
Author contributions: All the authors have accepted
responsibility for the entire content of this submitted
manuscript and approved submission.
Research funding: This work was supported by the
Intramural Research Program of the National Institutes of
Health, National Cancer Institute, Center for Cancer
Research [grant numbers ZIA BC 011513].
Conﬂict of interest statement: No potential conﬂicts ofinterest were disclosed.

References[1] Cancer. WHO, 2018. Available at: https://www.who.int/newsroom/fact-sheets/detail/cancer [accessed: Feb. 26, 2021].
[2] H. Sung, J. Ferlay, R. L. Siegel, et al., “Global cancer statistics
2020: GLOBOCAN estimates of incidence and mortality worldwide
for 36 cancers in 185 countries,” CA Cancer J. Clin., 2021. https://doi.org/10.3322/caac.21660, in press.
[3] C. Robert, “A decade of immune-checkpoint inhibitors in cancer
therapy,” Nat. Commun., vol. 11, p. 3801, 2020.
[4] J. Galon and D. Bruni, “Approaches to treat immune hot, alteredand cold tumours with combination immunotherapies,” Nat. Rev.
Drug Discov., vol. 18, pp. 197–218, 2019.
[5] P. Bonaventura, T. Shekarian, V. Alcazer, et al., “Cold tumors: A
therapeutic challenge for immunotherapy,” Front. Immunol.,vol. 10, p. 168, 2019.

12

H. Wakiyama et al.: Near infrared photoimmunotherapy[6] S. B. Dubbs, “The latest cancer agents and their complications,”
Emerg. Med. Clin., vol. 36, pp. 485–492, 2018.
[7] M. Mitsunaga, M. Ogawa, N. Kosaka, L. T. Rosenblum,
P. L. Choyke, and H. Kobayashi, “Cancer cell-selective in vivo
near infrared photoimmunotherapy targeting speciﬁc membrane
molecules,” Nat. Med., vol. 17, pp. 1685–1691, 2011.
[8] H. Kobayashi and P. L. Choyke, “Near-infrared
photoimmunotherapy of cancer,” Acc. Chem. Res., vol. 52,
pp. 2332–2339, 2019.
[9] K. Sato, T. Nakajima, P. L. Choyke, and H. Kobayashi, “Selective
cell elimination in vitro and in vivo from tissues and tumors using
antibodies conjugated with a near infrared phthalocyanine,”
RSC Adv., vol. 5, pp. 25105–25114, 2015.
[10] K. Sato, N. Sato, B. Xu, et al., “Spatially selective depletion of tumorassociated regulatory T cells with near-infrared
photoimmunotherapy,” Sci. Transl. Med., vol. 8, p. 352ra110, 2016.
[11] H. Jing, C. Weidensteiner, W. Reichardt, et al., “Imaging andselective elimination of glioblastoma stem cells with theranostic
near-infrared-labeled cd133-speciﬁc antibodies,” Theranostics,
vol. 6, pp. 862–874, 2016.
[12] K. Sato, K. Ando, S. Okuyama, et al., “Photoinduced ligand
release from a silicon phthalocyanine dye conjugated withmonoclonal antibodies: A mechanism of cancer cell cytotoxicity
after near-infrared photoimmunotherapy,” ACS Cent. Sci., vol. 4,
pp. 1559–1569, 2018.
[13] F. Ogata, T. Nagaya, S. Okuyama, et al., “Dynamic changes in thecell membrane on three dimensional low coherent quantitative
phase microscopy (3D LC-QPM) after treatment with the nearinfrared photoimmunotherapy,” Oncotarget, vol. 8,
pp. 104295–104302, 2017.
[14] T. A. Henderson and L. D. Morries, “Near-infrared photonic
energy penetration: can infrared phototherapy effectively reachthe human brain?” Neuropsychiatric Dis. Treat., vol. 11,
pp. 2191–2208, 2015.
[15] Y. Nakamura, Z. W. Ohler, D. Householder, et al., “Near infrared
photoimmunotherapy in a transgenic mouse model of
spontaneous epidermal growth factor receptor (EGFR)expressing lung cancer,” Mol. Canc. Therapeut., vol. 16,
pp. 408–414, 2017.
[16] K. Sato, T. Nagaya, Y. Nakamura, T. Harada, P. L. Choyke, andH. Kobayashi, “Near infrared photoimmunotherapy preventslung cancer metastases in a murine model,” Oncotarget, vol. 6,
pp. 19747–19758, 2015.
[17] K. Sato, T. Nagaya, M. Mitsunaga, P. L. Choyke, andH. Kobayashi, “Near infrared photoimmunotherapy for lungmetastases,” Canc. Lett., vol. 365, pp. 112–121, 2015.
[18] K. Sato, T. Nagaya, P. L. Choyke, and H. Kobayashi, “Nearinfrared photoimmunotherapy in the treatment of pleuraldisseminated NSCLC: preclinical experience,” Theranostics,
vol. 5, pp. 698–709, 2015.
[19] Y. Maruoka, T. Nagaya, K. Sato, et al., “Near infrared
photoimmunotherapy with combined exposure of external andinterstitial light sources,” Mol. Pharm., vol. 15, pp. 3634–3641,
2018.
[20] T. Nagaya, S. Okuyama, F. Ogata, Y. Maruoka, P. L. Choyke, andH. Kobayashi, “Endoscopic near infrared photoimmunotherapy
using a ﬁber optic diffuser for peritoneal dissemination of gastriccancer,” Canc. Sci., vol. 109, pp. 1902–1908, 2018.

[21] S. Okuyama, T. Nagaya, K. Sato, et al., “Interstitial near-infrared
photoimmunotherapy: effective treatment areas and light doses
needed for use with ﬁber optic diffusers,” Oncotarget, vol. 9,
p. 11159, 2018.
[22] K. Nakajima, T. Kimura, H. Takakura, et al., “Implantablewireless powered light emitting diode (LED) for near-infrared
photoimmunotherapy: device development and experimental
assessment in vitro and in vivo,” Oncotarget, vol. 9,
pp. 20048–20057, 2018.
[23] F. F. Inagaki, D. Fujimura, A. Furusawa, et al., “Diagnostic
imaging in near-infrared photoimmunotherapy using acommercially available camera for indocyanine green,” Canc.
Sci., vol. 18, no. 3, pp. 1238–1246, 2021.
[24] M. Ogawa, Y. Tomita, Y. Nakamura, et al., “Immunogenic cancer
cell death selectively induced by near infrared
photoimmunotherapy initiates host tumor immunity,”
Oncotarget, vol. 8, pp. 10425–10436, 2017.
[25] H. Kobayashi, A. Furusawa, A. Rosenberg, and P. L. Choyke,“Near-infrared photoimmunotherapy of cancer: A new approachthat kills cancer cells and enhances anti-cancer host immunity,”Int. Immunol., vol. 33, pp. 7–15, 2021.
[26] D. R. Green, T. Ferguson, L. Zitvogel, and G. Kroemer,“Immunogenic and tolerogenic cell death,” Nat. Rev. Immunol.,vol. 9, pp. 353–363, 2009.
[27] G. Kroemer, L. Galluzzi, O. Kepp, and L. Zitvogel, “Immunogenic
cell death in cancer therapy,” Annu. Rev. Immunol., vol. 31,
pp. 51–72, 2013.
[28] L. Galluzzi, I. Vitale, J. M. Abrams, et al., “Molecular deﬁnitions ofcell death subroutines: recommendations of the Nomenclature
Committee on Cell Death 2012,” Cell Death Differ., vol. 19,
pp. 107–120, 2012.
[29] D. V. Krysko, A. D. Garg, A. Kaczmarek, O. Krysko, P. Agostinis,
and P. Vandenabeele, “Immunogenic cell death and DAMPs incancer therapy,” Nat. Rev. Canc., vol. 12, pp. 860–875, 2012.
[30] L. Galluzzi, A. Buque, O. Kepp, L. Zitvogel, and G. Kroemer,“Immunogenic cell death in cancer and infectious disease,” Nat.
Rev. Immunol., vol. 17, pp. 97–111, 2017.
[31] T. Nagaya, J. Friedman, Y. Maruoka, et al., “Host immunity
following near-infrared photoimmunotherapy is enhanced with
PD-1 checkpoint blockade to eradicate established antigenic
tumors,” Canc. Immunol. Res., vol. 7, pp. 401–413, 2019.
[32] T. Nagaya, Y. Nakamura, S. Okuyama, et al., “Syngeneic mousemodels of oral cancer are effectively targeted by antiCD44-based NIR-PIT,” Mol. Canc. Res., vol. 15, pp. 1667–1677,
2017.
[33] Y. Maruoka, A. Furusawa, R. Okada, et al., “Near-infrared
photoimmunotherapy combined with CTLA4 checkpoint
blockade in syngeneic mouse cancer models,” Vaccines, vol. 8,
no. 3, p. 528, 2020.
[34] H. Wakiyama, A. Furusawa, R. Okada, et al., “Increased
immunogenicity of a minimally immunogenic tumor after cancertargeting near infrared photoimmunotherapy,” Cancers, vol. 12,
no. 12, p. 3747, 2020.
[35] ASP-1929 photoimmunotherapy (PIT) study in recurrent head/neck cancer for patients who have failed at least two lines oftherapy. ClinicalTrials.gov, 2020. Available at: https://clinicaltrials.gov/ct2/show/NCT03769506 [accessed: Feb. 26,
2021].

H. Wakiyama et al.: Near infrared photoimmunotherapy[36] R. Oun, Y. E. Moussa, and N. J. Wheate, “The side effects ofplatinum-based chemotherapy drugs: A review for chemists,”
Dalton Trans., vol. 47, pp. 6645–6653, 2018.
[37] L. Y. Ramirez, S. E. Huestis, T. Y. Yap, S. Zyzanski, D. Drotar, andE. Kodish, “Potential chemotherapy side effects: what do
oncologists tell parents?” Pediatr. Blood Canc., vol. 52,
pp. 497–502, 2009.
[38] S. K. Golombek, J. N. May, B. Theek, et al., “Tumor targeting via
EPR: strategies to enhance patient responses,” Adv. Drug Deliv.
Rev., vol. 130, pp. 17–38, 2018.
[39] Y. Matsumura and H. Maeda, “A new concept for macromoleculartherapeutics in cancer chemotherapy: mechanism oftumoritropic accumulation of proteins and the antitumor agent
smancs,” Canc. Res., vol. 46, pp. 6387–6392, 1986.
[40] H. Maeda, J. Wu, T. Sawa, Y. Matsumura, and K. Hori, “Tumor
vascular permeability and the EPR effect in macromoleculartherapeutics: A review,” J. Contr. Release, vol. 65, pp. 271–284,
2000.
[41] G. H. Petersen, S. K. Alzghari, W. Chee, S. S. Sankari, andN. M. La-Beck, “Meta-analysis of clinical and preclinical studies
comparing the anticancer efﬁcacy of liposomal versus
conventional non-liposomal doxorubicin,” J. Contr. Release, vol.
232, pp. 255–264, 2016.
[42] A. C. Anselmo and S. Mitragotri, “Nanoparticles in the clinic: An
update,” Bioeng. Transl. Med., vol. 4, no. 3, p. e10143, 2019.
[43] C. L. Ventola, “Progress in nanomedicine: approved andinvestigational nanodrugs,” P T, vol. 42, pp. 742–755, 2017.
[44] Y. Nakamura, A. Mochida, P. L. Choyke, and H. Kobayashi,“Nanodrug delivery: is the enhanced permeability and retention
effect sufﬁcient for curing cancer?” Bioconjugate Chem., vol. 27,
pp. 2225–2238, 2016.
[45] G. Manoukian and F. Hagemeister, “Denileukin diftitox: A novel
immunotoxin,” Expet Opin. Biol. Ther., vol. 9, pp. 1445–1451,
2009.
[46] D. J. Green and O. W. Press, “Whither radioimmunotherapy: to
Be or not to Be?” Canc. Res., vol. 77, pp. 2191–2196, 2017.
[47] Y. Wang and D. S. Kohane, “External triggering and triggered
targeting strategies for drug delivery,” Nat. Rev. Mater., vol. 2,
p. 17020, 2017.
[48] T. Ta and T. M. Porter, “Thermosensitive liposomes for localized
delivery and triggered release of chemotherapy,” J. Contr.
Release, vol. 169, pp. 112–125, 2013.
[49] Y. Bae, N. Nishiyama, S. Fukushima, H. Koyama, M. Yasuhiro,
and K. Kataoka, “Preparation and biological characterizationof polymeric micelle drug carriers with intracellular
pH-triggered drug release Property: tumor permeability,
controlled subcellular drug distribution, and enhanced in vivo
antitumor efﬁcacy,” Bioconjugate Chem., vol. 16, pp. 122–130,
2005.
[50] R. K. Jain, “Molecular regulation of vessel maturation,” Nat.
Med., vol. 9, pp. 685–693, 2003.
[51] M. W. Dewhirst and T. W. Secomb, “Transport of drugs fromblood vessels to tumour tissue,” Nat. Rev. Canc., vol. 17,
pp. 738–750, 2017.
[52] T. Stylianopoulos, J. D. Martin, V. P. Chauhan, et al., “Causes,
consequences, and remedies for growth-induced solid stress inmurine and human tumors,” Proc. Natl. Acad. Sci. U. S. A., vol.
109, pp. 15101–15108, 2012.

13[53] F. F. Inagaki, A. Furusawa, P. L. Choyke, and H. Kobayashi,“Enhanced nanodrug delivery in tumors after near-infrared
photoimmunotherapy,” Nanophotonics, vol. 8, pp. 1673–1688,2019.
[54] K. Sano, T. Nakajima, P. L. Choyke, and H. Kobayashi, “Markedly
enhanced permeability and retention effects induced by photoimmunotherapy of tumors,” ACS Nano, vol. 7, pp. 717–724, 2013.
[55] H. Kobayashi and P. L. Choyke, “Super enhanced permeability
and retention (SUPR) effects in tumors following near infrared
photoimmunotherapy,” Nanoscale, vol. 8, pp. 12504–12509,
2016.
[56] K. Sano, T. Nakajima, P. L. Choyke, and H. Kobayashi, “The effectof photoimmunotherapy followed by liposomal daunorubicin ina mixed tumor model: A demonstration of the super-enhanced
permeability and retention effect after photoimmunotherapy,”
Mol. Canc. Therapeut., vol. 13, pp. 426–432, 2014.
[57] H. Hanaoka, T. Nakajima, K. Sato, et al., “Photoimmunotherapyof hepatocellular carcinoma-targeting Glypican-3 combined withnanosized albumin-bound paclitaxel,” Nanomedicine, vol. 10,
pp. 1139–1147, 2015.
[58] R. Okada, Y. Maruoka, A. Furusawa, et al., “The effect of antibody
fragments on CD25 targeted regulatory T cell near-infrared
photoimmunotherapy,” Bioconjugate Chem., vol. 30,
pp. 2624–2633, 2019.
[59] R. Okada, T. Kato, A. Furusawa, et al., “Local depletion of
immune checkpoint ligand CTLA4 expressing cells in tumor
beds enhances antitumor host immunity,” Adv. Therap., n/a,p. 2000269, 2021. https://doi.org/10.1002/adtp.202000269.
[60] D. E. Johnson, B. Burtness, C. R. Leemans, V. W. Y. Lui,
J. E. Bauman, and J. R. Grandis, “Head and neck squamous cell
carcinoma,” Nat. Rev. Dis. Prim., vol. 6, p. 92, 2020.
[61] Chow LQM, “Head and neck cancer,” N. Engl. J. Med., vol. 382,
pp. 60–72, 2020.
[62] M. A. List and S. P. Bilir, “Functional outcomes in head and neckcancer,” Semin. Radiat. Oncol., vol. 14, pp. 178–189, 2004.
[63] S. Kalyankrishna and J. R. Grandis, “Epidermal growth factor
receptor biology in head and neck cancer,” J. Clin. Oncol., vol. 24,
pp. 2666–2672, 2006.
[64] Study of RM-1929 and photoimmunotherapy in patients withrecurrent head and neck cancer. ClinicalTrials.gov, 2020.
Avaliable at: https://clinicaltrials.gov/ct2/show/NCT02422979[accessed: Feb. 26, 2021].
[65] J. Chen, J. Zhou, J. Lu, H. Xiong, X. Shi, and L. Gong, “Signiﬁcanceof CD44 expression in head and neck cancer: A systemic review
and meta-analysis,” BMC Canc., vol. 14, p. 15, 2014.
[66] B. M. Alexander and T. F. Cloughesy, “Adult glioblastoma,”
J. Clin. Oncol., vol. 35, pp. 2402–2409, 2017.
[67] A. Omuro and L. M. DeAngelis, “Glioblastoma and othermalignant gliomas: A clinical review,” J. Am. Med. Assoc., vol.
310, pp. 1842–1850, 2013.
[68] Q. T. Ostrom, G. Ciofﬁ, H. Gittleman, et al., “CBTRUS statisticalreport: primary brain and other central nervous system tumors
diagnosed in the United States in 2012-2016,” Neuro Oncol., vol.
21, pp. v1–v100, 2019.
[69] P. Farina, G. Lombardi, E. Bergo, A. Roma, and V. Zagonel,“Treatment of malignant gliomas in elderly patients: A concise
overview of the literature,” BioMed Res. Int., vol. 2014,
p. 734281, 2014.

14

H. Wakiyama et al.: Near infrared photoimmunotherapy[70] M. C. Chamberlain, “Radiographic patterns of relapse in
glioblastoma,” J. Neuro Oncol., vol. 101, pp. 319–323, 2011.
[71] F. H. Hochberg and A. Pruitt, “Assumptions in the radiotherapy ofglioblastoma,” Neurology, vol. 30, pp. 907–911, 1980.
[72] K. E. Wallner, J. H. Galicich, G. Krol, E. Arbit, and M. G. Malkin,“Patterns of failure following treatment for glioblastoma
multiforme and anaplastic astrocytoma,” Int. J. Radiat. Oncol.
Biol. Phys., vol. 16, pp. 1405–1409, 1989.
[73] K. Petrecca, M. C. Guiot, V. Panet-Raymond, and L. Souhami,“Failure pattern following complete resection plus radiotherapy
and temozolomide is at the resection margin in patients withglioblastoma,” J. Neuro Oncol., vol. 111, pp. 19–23, 2013.
[74] T. A. Libermann, N. Razon, A. D. Bartal, Y. Yarden,
J. Schlessinger, and H. Soreq, “Expression of epidermal growth
factor receptors in human brain tumors,” Canc. Res., vol. 44,
pp. 753–760, 1984.
[75] T. A. Libermann, H. R. Nusbaum, N. Razon, et al., “Ampliﬁcation,enhanced expression and possible rearrangement of EGF
receptor gene in primary human brain tumours of glial origin,”
Nature, vol. 313, pp. 144–147, 1985.
[76] N. Shinojima, K. Tada, S. Shiraishi, et al., “Prognostic value of
epidermal growth factor receptor in patients with glioblastoma
multiforme,” Canc. Res., vol. 63, pp. 6962–6970, 2003.
[77] T. A. Burley, J. Maczynska, A. Shah, et al., “Near-infrared
photoimmunotherapy targeting EGFR-Shedding new light on
glioblastoma treatment,” Int. J. Canc., vol. 142, pp. 2363–2374, 2018.
[78] J. D. Lathia, S. C. Mack, E. E. Mulkearns-Hubert, C. L. L. Valentim,
and J. N. Rich, “Cancer stem cells in glioblastoma,” Genes Dev.,
vol. 29, pp. 1203–1217, 2015.
[79] R. Chen, M. C. Nishimura, S. M. Bumbaca, et al., “A hierarchy ofself-renewing tumor-initiating cell types in glioblastoma,” Canc.
Cell, vol. 17, pp. 362–375, 2010.
[80] S. K. Singh, C. Hawkins, I. D. Clarke, et al., “Identiﬁcation ofhuman brain tumour initiating cells,” Nature, vol. 432,
pp. 396–401, 2004.
[81] S. Bao, Q. Wu, S. Sathornsumetee, et al., “Stem cell-like glioma
cells promote tumor angiogenesis through vascular endothelial
growth factor,” Canc. Res., vol. 66, pp. 7843–7848, 2006.
[82] E. C. Smyth, J. Lagergren, R. C. Fitzgerald, et al., “Oesophageal
cancer,” Nat. Rev. Dis. Prim., vol. 3, p. 17048, 2017.
[83] H. Mukaida, M. Toi, T. Hirai, Y. Yamashita, and T. Toge, “Clinicalsigniﬁcance of the expression of epidermal growth factor and its
receptor in esophageal cancer,” Cancer, vol. 68, pp. 142–148,
1991.
[84] Y. Itakura, H. Sasano, C. Shiga, et al., “Epidermal growth factor
receptor overexpression in esophageal carcinoma. An
immunohistochemical study correlated with clinicopathologic
ﬁndings and DNA ampliﬁcation,” Cancer, vol. 74, pp. 795–804, 1994.
[85] K. L. Wang, T. T. Wu, I. S. Choi, et al., “Expression of epidermal
growth factor receptor in esophageal and esophagogastricjunction adenocarcinomas: association with poor outcome,”
Cancer, vol. 109, pp. 658–667, 2007.
[86] D. Navarini, R. R. Gurski, C. A. Madalosso, L. Aita, L. Meurer, andF. Fornari, “Epidermal growth factor receptor expression inesophageal adenocarcinoma: relationship with tumor stage andsurvival after esophagectomy,” Gastroenterol. Res. Pract., vol.
2012, p. 941954, 2012.
[87] L. Yacoub, H. Goldman, and R. D. Odze, “Transforming growth
factor-alpha, epidermal growth factor receptor, and MiB-1
expression in Barrett’s-associated neoplasia: correlation withprognosis,” Mod. Pathol. : Off. J. U. S. Can. Acad. Pathol. Inc.,
vol. 10, pp. 105–112, 1997.
[88] N. Zhan, W. G. Dong, Y. F. Tang, Z. S. Wang, and C. L. Xiong,“Analysis of HER2 gene ampliﬁcation and protein expression inesophageal squamous cell carcinoma,” Med. Oncol., vol. 29,
pp. 933–940, 2012.
[89] E. Van Cutsem, Y. J. Bang, F. Feng-Yi, et al., “HER2 screening
data from ToGA: targeting HER2 in gastric andgastroesophageal junction cancer,” Gastric Cancer, vol. 18,
pp. 476–484, 2015.
[90] Cancer Genome Atlas Research N, Analysis Working Group:
Asan U, Agency BCC, et al., “Integrated genomic
characterization of oesophageal carcinoma,” Nature, vol. 541,
pp. 169–175, 2017.
[91] E. Hartmans, M. D. Linssen, C. Sikkens, et al., “Tyrosine kinase
inhibitor induced growth factor receptor upregulation enhances
the efﬁcacy of near-infrared targeted photodynamic therapy inesophageal adenocarcinoma cell lines,” Oncotarget, vol. 8,
pp. 29846–29856, 2017.
[92] T. Kato, K. Noma, T. Ohara, et al., “Cancer-associatedﬁbroblasts affect intratumoral CD8(+) and FoxP3(+) T cells via
IL6 in the tumor microenvironment,” Clin. Canc. Res., vol. 24,
pp. 4820–4833, 2018.
[93] H. Kashima, K. Noma, T. Ohara, et al., “Cancer-associatedﬁbroblasts (CAFs) promote the lymph node metastasis ofesophageal squamous cell carcinoma,” Int. J. Canc., vol. 144,
pp. 828–840, 2019.
[94] S. Watanabe, K. Noma, T. Ohara, et al., “Photoimmunotherapy forcancer-associated ﬁbroblasts targeting ﬁbroblast activation protein
in human esophageal squamous cell carcinoma,” Canc. Biol. Ther.,vol. 20, no. 9, pp. 1234–1248, 2019.
[95] R. Katsube, K. Noma, T. Ohara, et al., “Fibroblast activation
protein targeted near infrared photoimmunotherapy (NIR PIT)
overcomes therapeutic resistance in human esophageal
cancer,” Sci. Rep., vol. 11, p. 1693, 2021.
[96] N. Duma, R. Santana-Davila, and J. R. Molina, “Non-small celllung cancer: epidemiology, screening, diagnosis, andtreatment,” Mayo Clin. Proc., vol. 94, pp. 1623–1640, 2019.
[97] R. S. Herbst, “Review of epidermal growth factor receptor biology,”
Int. J. Radiat. Oncol. Biol. Phys., vol. 59, pp. 21–26, 2004.
[98] S. M. Ansell, A. M. Lesokhin, I. Borrello, et al., “PD-1 blockadewith nivolumab in relapsed or refractory Hodgkin’s lymphoma,”
N. Engl. J. Med., vol. 372, pp. 311–319, 2015.
[99] J. R. Brahmer, S. S. Tykodi, L. Q. Chow, et al., “Safety and activityof anti-PD-L1 antibody in patients with advanced cancer,”N. Engl. J. Med., vol. 366, pp. 2455–2465, 2012.
[100] R. S. Herbst, J. C. Soria, M. Kowanetz, et al., “Predictive
correlates of response to the anti-PD-L1 antibody MPDL3280A
in cancer patients,” Nature, vol. 515, pp. 563–567, 2014.
[101] T. Nagaya, Y. Nakamura, K. Sato, et al., “Near infrared
photoimmunotherapy with avelumab, an anti-programmed
death-ligand 1 (PD-L1) antibody,” Oncotarget, vol. 8,
pp. 8807–8817, 2017.
[102] W. N. William, Jr. and B. S. Glisson, “Novel strategies for thetreatment of small-cell lung carcinoma,” Nat. Rev. Clin. Oncol.,vol. 8, pp. 611–619, 2011.
[103] L. R. Saunders, A. J. Bankovich, W. C. Anderson, et al., “A
DLL3-targeted antibody-drug conjugate eradicates high-grade
pulmonary neuroendocrine tumor-initiating cells in vivo,” Sci.
Transl. Med., vol. 7, p. 302ra136, 2015.

H. Wakiyama et al.: Near infrared photoimmunotherapy[104] Y. Isobe, K. Sato, Y. Nishinaga, et al., “Near infrared
photoimmunotherapy targeting DLL3 for small cell lungcancer,” EBioMedicine, vol. 52, p. 102632, 2020.
[105] P. Mordant, A. Arame, C. Foucault, A. Dujon,
F. Le Pimpec Barthes, and M. Riquet, “Surgery for metastatic
pleural extension of non-small-cell lung cancer,” Eur. J. Cardio.
Thorac. Surg., vol. 40, pp. 1444–1449, 2011.
[106] A. C. Bibby, S. Tsim, N. Kanellakis, et al., “Malignant pleural
mesothelioma: An update on investigation, diagnosis andtreatment,” Eur. Respir. Rev., vol. 25, pp. 472–486, 2016.
[107] V. Schacht, M. I. Ramirez, Y. K. Hong, et al., “T1alpha/podoplanin deﬁciency disrupts normal lymphatic vasculatureformation and causes lymphedema,” EMBO J., vol. 22,
pp. 3546–3556, 2003.
[108] M. Quintanilla, L. Montero-Montero, J. Renart, andE. Martin-Villar, “Podoplanin in inﬂammation and cancer,” Int.
J. Mol. Sci., vol. 20, 2019, https://doi.org/10.3390/
ijms20030707.
[109] W. Y. Chuang, Y. S. Chang, C. J. Yeh, Y. C. Wu, and C. Hsueh,“Role of podoplanin expression in squamous cell carcinoma of
upper aerodigestive tract,” Histol. Histopathol., vol. 28,
pp. 293–299, 2013.
[110] Y. Nishinaga, K. Sato, H. Yasui, et al., “Targeted phototherapy
for malignant pleural mesothelioma: near-infrared
photoimmunotherapy targeting podoplanin,” Cells, vol. 9,
2020, https://doi.org/10.3390/cells9041019.
[111] N. G. Ordóñez, “Application of mesothelin immunostaining intumor diagnosis,” Am. J. Surg. Pathol., vol. 27, pp. 1418–1428,
2003.
[112] R. Hassan and M. Ho, “Mesothelin targeted cancer
immunotherapy,” Eur. J. Canc., vol. 44, pp. 46–53, 2008.
[113] T. Nagaya, Y. Nakamura, K. Sato, et al., “Near infrared
photoimmunotherapy with an anti-mesothelin antibody,”
Oncotarget, vol. 7, pp. 23361–23369, 2016.
[114] A. G. Waks and E. P. Winer, “Breast cancer treatment: A review,”
J. Am. Med. Assoc., vol. 321, pp. 288–300, 2019.
[115] R. L. B. Costa and B. J. Czerniecki, “Clinical development of
immunotherapies for HER2(+) breast cancer: A review of
HER2-directed monoclonal antibodies and beyond,” NPJ Breast
Canc., vol. 6, p. 10, 2020.
[116] F. Salvador, A. Llorente, and R. R. Gomis, “From latency to overtbone metastasis in breast cancer: potential for treatment andprevention,” J. Pathol., vol. 249, pp. 6–18, 2019.
[117] L. Livraghi and J. E. Garber, “PARP inhibitors in the managementof breast cancer: current data and future prospects,” BMC Med.,
vol. 13, p. 188, 2015.
[118] K. Shimoyama, S. Kagawa, M. Ishida, et al., “Viral transductionof the HER2-extracellular domain expands trastuzumab-based
photoimmunotherapy for HER2-negative breast cancer cells,”
Breast Canc. Res. Treat., vol. 149, pp. 597–605, 2015.
[119] M. L. Burness, T. A. Grushko, and O. I. Olopade, “Epidermal
growth factor receptor in triple-negative and basal-like breast
cancer: promising clinical target or only a marker?” Canc. J., vol.
16, 2010, https://doi.org/10.1097/ppo.0b013e3181d24fc1.
[120] A. A. Changavi, A. Shashikala, and A. S. Ramji, “Epidermal
growth factor receptor expression in triple negative andnontriple negative breast carcinomas,” J. Lab. Phys., vol. 7,
pp. 79–83, 2015.
[121] T. Nagaya, K. Sato, T. Harada, Y. Nakamura, P. L. Choyke, andH. Kobayashi, “Near infrared photoimmunotherapy targeting

15

EGFR positive triple negative breast cancer: optimizing the
conjugate-light regimen,” PloS One, vol. 10, p. e0136829, 2015.
[122] J. A. Ajani, J. Lee, T. Sano, Y. Y. Janjigian, D. Fan, and S. Song,“Gastric adenocarcinoma,” Nat. Rev. Dis. Prim., vol. 3, p. 17036,
2017.
[123] Y. J. Bang, E. Van Cutsem, A. Feyereislova, et al., “Trastuzumab in
combination with chemotherapy versus chemotherapy alone fortreatment of HER2-positive advanced gastric or gastro-oesophageal
junction cancer (ToGA): A phase 3, open-label, randomised
controlled trial,” Lancet, vol. 376, pp. 687–697, 2010.
[124] K. Sato, P. L. Choyke, and H. Kobayashi, “Photoimmunotherapy
of gastric cancer peritoneal carcinomatosis in a mouse model,”PloS One, vol. 9, p. e113276, 2014.
[125] K. Ito, M. Mitsunaga, S. Arihiro, et al., “Molecular targeted
photoimmunotherapy for HER2-positive human gastric cancer
in combination with chemotherapy results in improved
treatment outcomes through different cytotoxic mechanisms,”
BMC Canc., vol. 16, p. 37, 2016.
[126] K. Ito, M. Mitsunaga, T. Nishimura, H. Kobayashi, and H. Tajiri,“Combination photoimmunotherapy with monoclonal
antibodies recognizing different epitopes of human epidermal
growth factor receptor 2: An assessment of phototherapeutic
effect based on ﬂuorescence molecular imaging,” Oncotarget,
vol. 7, pp. 14143–14152, 2016.
[127] G. Cheng, Y. Mei, X. Pan, M. Liu, and S. Wu, “Expression of
HER2/c-erbB-2, EGFR protein in gastric carcinoma and its
clinical signiﬁcance,” Open Life Sci., vol. 14, pp. 119–125, 2019.
[128] M. Gao, X-J. Liang, Z-S. Zhang, W. Ma, Z-W. Chang, and
M-Z. Zhang, “Relationship between expression of EGFR ingastric cancer tissue and clinicopathological features,” Asian
Pac. J. Trop. Med., vol. 6, pp. 260–264, 2013.
[129] G. Galizia, E. Lieto, M. Orditura, et al., “Epidermal growth factor
receptor (EGFR) expression is associated with a worse
prognosis in gastric cancer patients undergoing curative
surgery,” World J. Surg., vol. 31, pp. 1458–1468, 2007.
[130] E. Dekker, P. J. Tanis, J. L. A. Vleugels, P. M. Kasi, andM. B. Wallace, “Colorectal cancer,” Lancet, vol. 394,
pp. 1467–1480, 2019.
[131] S. Hammarström, “The carcinoembryonic antigen (CEA) family:
structures, suggested functions and expression in normal andmalignant tissues,” Semin. Canc. Biol., vol. 9, pp. 67–81, 1999.
[132] D. Boucher, D. Cournoyer, C. P. Stanners, and A. Fuks, “Studies
on the control of gene expression of the carcinoembryonicantigen family in human tissue,” Canc. Res., vol. 49,
pp. 847–852, 1989.
[133] G. Tong, W. Xu, G. Zhang, et al., “The role of tissue and serum
carcinoembryonic antigen in stages I to III of colorectal cancer-A
retrospective cohort study,” Canc. Med., vol. 7, pp. 5327–5338,
2018.
[134] J. W. Park, H. J. Chang, B. C. Kim, H. Y. Yeo, and D. Y. Kim,
“Clinical validity of tissue carcinoembryonic antigen expression
as ancillary to serum carcinoembryonic antigen concentrationin patients curatively resected for colorectal cancer,” Colorectal
Dis., vol. 15, pp. e503–e511, 2013.
[135] N. Shirasu, H. Yamada, H. Shibaguchi, M. Kuroki, and M. Kuroki,“Potent and speciﬁc antitumor effect of CEA-targeted
photoimmunotherapy,” Int. J. Canc., vol. 135, pp. 2697–2710,
2014.
[136] H. M. Hollandsworth, S. Amirfakhri, F. Filemoni, et al., “Nearinfrared photoimmunotherapy is effective treatment for16

H. Wakiyama et al.: Near infrared photoimmunotherapy

colorectal cancer in orthotopic nude-mouse models,” PloS One,
vol. 15, p. e0234643, 2020.
[137] J. K. Heath, S. J. White, C. N. Johnstone, et al., “The human A33
antigen is a transmembrane glycoprotein and a novel memberof the immunoglobulin superfamily,” Proc. Natl. Acad. Sci. U. S.
A., vol. 94, pp. 469–474, 1997.
[138] D. Wei, Z. Tao, Q. Shi, et al., “Selective photokilling of colorectal
tumors by near-infrared photoimmunotherapy with a
GPA33-targeted single-chain antibody variable fragment
conjugate,” Mol. Pharm., vol. 17, pp. 2508–2517, 2020.
[139] C-W. Huang, Y-T. Chen, H-L. Tsai, et al., “EGFR expression inpatients with stage III colorectal cancer after adjuvant
chemotherapy and on cancer cell function,” Oncotarget, vol. 8,
pp. 114663–114676, 2017.
[140] J. Liu, Q. Zhou, J. Xu, J. Wang, and Y. Zhang, “Detection of EGFR
expression in patients with colorectal cancer and thetherapeutic effect of cetuximab,” J. BUON: Off. J. Balk. Union
Oncol., vol. 21, pp. 95–100, 2016.
[141] G. E. Theodoropoulos, E. Karafoka, J. G. Papailiou, et al., “P53
and EGFR expression in colorectal cancer: A reappraisal of ‘old’
tissue markers in patients with long follow-up,” Anticanc. Res.,
vol. 29, pp. 785–791, 2009.
[142] J. P. Spano, C. Lagorce, D. Atlan, et al., “Impact of EGFR
expression on colorectal cancer patient prognosis andsurvival,” Ann. Oncol., vol. 16, pp. 102–108, 2005.
[143] Y. H. Xie, Y. X. Chen, and J. Y. Fang, “Comprehensive review oftargeted therapy for colorectal cancer,” Signal Transduct.
Target Ther., vol. 5, p. 22, 2020.
[144] D. Baumhoer, L. Tornillo, S. Stadlmann, M. Roncalli,
E. K. Diamantis, and L. M. Terracciano, “Glypican 3 expression
in human nonneoplastic, preneoplastic, and neoplastic
tissues: A tissue microarray analysis of 4,387 tissue samples,”Am. J. Clin. Pathol., vol. 129, pp. 899–906, 2008.
[145] H. Hanaoka, T. Nagaya, K. Sato, et al., “Glypican-3 targeted
human heavy chain antibody as a drug carrier forhepatocellular carcinoma therapy,” Mol. Pharm., vol. 12,
pp. 2151–2157, 2015.
[146] J. M. Banales, J. J. G. Marin, A. Lamarca, et al.,
“Cholangiocarcinoma 2020: the next horizon in mechanisms
and management,” Nat. Rev. Gastroenterol. Hepatol., vol. 17,
pp. 557–588, 2020.
[147] H. Hirata, M. Kuwatani, K. Nakajima, et al., “Near-infrared
photoimmunotherapy (NIR-PIT) on cholangiocarcinoma using anovel catheter device with light emitting diodes,” Canc. Sci.,
vol. 112, no. 2, pp. 828–838, 2020.
[148] D. M. Goldenberg, T. M. Cardillo, S. V. Govindan, E. A. Rossi,
and R. M. Sharkey, “Trop-2 is a novel target for solid cancer
therapy with sacituzumab govitecan (IMMU-132), an antibodydrug conjugate (ADC),” Oncotarget, vol. 6, pp. 22496–22512,
2015.
[149] A. Shvartsur and B. Bonavida, “Trop2 and its overexpression incancers: regulation and clinical/therapeutic implications,”
Genes Canc., vol. 6, pp. 84–105, 2015.
[150] T. Nishimura, M. Mitsunaga, R. Sawada, et al.,“Photoimmunotherapy targeting biliary-pancreatic cancer withhumanized anti-TROP2 antibody,” Canc. Med., vol. 8,
pp. 7781–7792, 2019.
[151] L. Moletta, S. Seraﬁni, M. Valmasoni, E. S. Pierobon, A. Ponzoni,
and C. Sperti, “Surgery for recurrent pancreatic cancer: is it
effective?,” Cancers, vol. 11, no. 7, p. 991, 2019.

[152] A. A. Maawy, Y. Hiroshima, Y. Zhang, et al., “Near infra-red
photoimmunotherapy with anti-CEA-IR700 results in extensive
tumor lysis and a signiﬁcant decrease in tumor burden inorthotopic mouse models of pancreatic cancer,” PloS One, vol.
10, p. e0121989, 2015.
[153] Y. L. Lum, J. M. Luk, D. E. Staunton, D. K. P. Ng, and W. P. Fong,“Cadherin-17 targeted near-infrared photoimmunotherapy fortreatment of gastrointestinal cancer,” Mol. Pharm., vol. 17,
pp. 3941–3951, 2020.
[154] Y. Hiroshima, A. Maawy, Y. Zhang, et al., “Photoimmunotherapy
inhibits tumor recurrence after surgical resection on apancreatic cancer patient-derived orthotopic xenograft (PDOX)
nude mouse model,” Ann. Surg Oncol., vol. 22, no. Suppl 3,
pp. S1469–S1474, 2015.
[155] A. A. Maawy, Y. Hiroshima, Y. Zhang, et al.,“Photoimmunotherapy lowers recurrence after pancreaticcancer surgery in orthotopic nude mouse models,” J. Surg. Res.,
vol. 197, pp. 5–11, 2015.
[156] S. J. Park, M. J. Gu, D. S. Lee, S. S. Yun, H. J. Kim, and J. H. Choi,“EGFR expression in pancreatic intraepithelial neoplasia andductal adenocarcinoma,” Int. J. Clin. Exp. Pathol., vol. 8,
pp. 8298–8304, 2015.
[157] A. Handra-Luca, P. Hammel, A. Sauvanet, C. Lesty,
P. Ruszniewski, and A. Couvelard, “EGFR expression inpancreatic adenocarcinoma. Relationship to tumourmorphology and cell adhesion proteins,” J. Clin. Pathol., vol. 67,
pp. 295–300, 2014.
[158] M. Bloomston, A. Bhardwaj, E. C. Ellison, and W. L. Frankel,“Epidermal growth factor receptor expression in pancreatic
carcinoma using tissue microarray technique,” Dig. Surg., vol.
23, pp. 74–79, 2006.
[159] B. M. Reid, J. B. Permuth, and T. A. Sellers, “Epidemiology of ovariancancer: A review,” Canc. Biol. Med., vol. 14, pp. 9–32, 2017.
[160] U. A. Matulonis, A. K. Sood, L. Fallowﬁeld, B. E. Howitt,
J. Sehouli, and B. Y. Karlan, “Ovarian cancer,” Nat. Rev. Dis.
Prim., vol. 2, p. 16061, 2016.
[161] N. S. Horowitz, A. Miller, B. Rungruang, et al., “Does aggressive
surgery improve outcomes? Interaction between preoperative
disease burden and complex surgery in patients with advancedstage ovarian cancer: An analysis of GOG 182,” J. Clin. Oncol.,vol. 33, pp. 937–943, 2015.
[162] S. J. Chang, M. Hodeib, J. Chang, and R. E. Bristow, “Survival
impact of complete cytoreduction to no gross residual disease
for advanced-stage ovarian cancer: A meta-analysis,” Gynecol.
Oncol., vol. 130, pp. 493–498, 2013.
[163] C. Pomel, A. Jeyarajah, D. Oram, et al., “Cytoreductive surgery inovarian cancer,” Canc. Imag., vol. 7, pp. 210–215, 2007.
[164] K. Sato, H. Hanaoka, R. Watanabe, T. Nakajima, P. L. Choyke,
and H. Kobayashi, “Near infrared photoimmunotherapy
in the treatment of disseminated peritoneal ovariancancer,” Mol. Canc. Therapeut., vol. 14, pp. 141–150,
2015.
[165] Y. Hama, Y. Urano, Y. Koyama, et al., “In vivo spectral
ﬂuorescence imaging of submillimeter peritoneal cancer
implants using a lectin-targeted optical agent,” Neoplasia,
vol. 8, pp. 607–612, 2006.
[166] T. Harada, Y. Nakamura, K. Sato, et al., “Near-infrared
photoimmunotherapy with galactosyl serum albumin in amodel of diffuse peritoneal disseminated ovarian cancer,”
Oncotarget, vol. 7, pp. 79408–79416, 2016.

H. Wakiyama et al.: Near infrared photoimmunotherapy[167] O. Sanli, J. Dobruch, M. A. Knowles, et al., “Bladder cancer,”Nat. Rev. Dis. Prim., vol. 3, p. 17022, 2017.
[168] N. H. Chow, S. H. Chan, T. S. Tzai, C. L. Ho, and H. S. Liu,
“Expression proﬁles of ErbB family receptors and prognosis in
primary transitional cell carcinoma of the urinary bladder,” Clin.
Canc. Res., vol. 7, pp. 1957–1962, 2001.
[169] R. Railkar, L. S. Krane, Q. Q. Li, et al., “Epidermal growth factor
receptor (EGFR)-targeted photoimmunotherapy (PIT) for thetreatment of EGFR-expressing bladder cancer,” Mol. Canc.
Therapeut., vol. 16, pp. 2201–2214, 2017.
[170] T. Nagaya, S. Okuyama, F. Ogata, et al., “Near infrared
photoimmunotherapy targeting bladder cancer with a canine
anti-epidermal growth factor receptor (EGFR) antibody,”
Oncotarget, vol. 9, pp. 19026–19038, 2018.
[171] M. R. Siddiqui, R. Railkar, T. Sanford, et al., “Targeting
epidermal growth factor receptor (EGFR) and human epidermal
growth factor receptor 2 (HER2) expressing bladder cancer
using combination photoimmunotherapy (PIT),” Sci. Rep., vol.
9, p. 2084, 2019.
[172] K. S. Chan, I. Espinosa, M. Chao, et al., “Identiﬁcation,
molecular characterization, clinical prognosis, and therapeutictargeting of human bladder tumor-initiating cells,” Proc. Natl.
Acad. Sci. U. S. A., vol. 106, pp. 14016–14021, 2009.
[173] B. Kiss, N. S. van den Berg, R. Ertsey, et al., “CD47-Targetednear-infrared photoimmunotherapy for human bladdercancer,” Clin. Canc. Res., vol. 25, no. 12, pp. 3561–3571, 2019.
[174] U. Haberkorn, M. Eder, K. Kopka, J. W. Babich, and M. Eisenhut,“New strategies in prostate cancer: prostate-speciﬁc
membrane antigen (PSMA) ligands for diagnosis and therapy,”
Clin. Canc. Res., vol. 22, pp. 9–15, 2016.
[175] T. Nagaya, Y. Nakamura, S. Okuyama, et al., “Near-infrared
photoimmunotherapy targeting prostate cancer with prostatespeciﬁc membrane antigen (PSMA) antibody,” Mol. Canc. Res.,
vol. 15, pp. 1153–1162, 2017.
[176] R. Watanabe, H. Hanaoka, K. Sato, et al.,“Photoimmunotherapy targeting prostate-speciﬁc membrane
antigen: are antibody fragments as effective as antibodies?”
J. Nucl. Med., vol. 56, pp. 140–144, 2015.
[177] K. Bouchelouche, B. Turkbey, and P. L. Choyke, “PSMA PET andradionuclide therapy in prostate cancer,” Semin. Nucl. Med.,
vol. 46, pp. 522–535, 2016.
[178] E. Sabattini, F. Bacci, C. Sagramoso, and S. A. Pileri, “WHOclassiﬁcation of tumours of haematopoietic and lymphoid17

tissues in 2008: An overview,” Pathologica, vol. 102,
pp. 83–87, 2010.
[179] C. Chung, “Current targeted therapies in lymphomas,” Am.
J. Health Syst. Pharm., vol. 76, pp. 1825–1834, 2019.
[180] T. Nagaya, Y. Nakamura, K. Sato, T. Harada, P. L. Choyke,
and H. Kobayashi, “Near infrared photoimmunotherapy of
B-cell lymphoma,” Mol. Oncol., vol. 10, pp. 1404–1414,
2016.
[181] Y. D. Heryanto, H. Hanaoka, T. Nakajima, A. Yamaguchi, and
Y. Tsushima, “Applying near-infrared photoimmunotherapy to
B-cell lymphoma: comparative evaluation withradioimmunotherapy in tumor xenografts,” Ann. Nucl. Med.,
vol. 31, pp. 669–677, 2017.
[182] G. I. Al Hothali, “Review of the treatment of mycosis fungoides
and Sézary syndrome: A stage-based approach,” Int. J. HealthSci., vol. 7, pp. 220–239, 2013.
[183] C. M. Magro and M. E. Dyrsen, “Cutaneous lymphocyte antigen
expression in benign and neoplastic cutaneous B- and T-cell
lymphoid inﬁltrates,” J. Cutan. Pathol., vol. 35, pp. 1040–1049,
2008.
[184] M. Silic-Benussi, A. Saponeri, A. Michelotto, et al., “Nearinfrared photoimmunotherapy targeting the cutaneous
lymphocyte antigen for mycosis fungoides,” Expet Opin. Biol.
Ther., pp. 1–5, 2020, https://doi.org/10.1080/14712598.2021.
1858791.
[185] B. Domingues, J. M. Lopes, P. Soares, and H. Populo,“Melanoma treatment in review,” ImmunoTargets Ther., vol. 7,
pp. 35–49, 2018.
[186] D. E. Dye, S. Medic, M. Ziman, and D. R. Coombe, “Melanoma
biomolecules: independently identiﬁed but functionallyintertwined,” Front. Oncol., vol. 3, p. 252, 2013.
[187] W. Wei, D. Jiang, E. B. Ehlerding, et al., “CD146-Targeted
multimodal image-guided photoimmunotherapy ofmelanoma,” Adv. Sci., vol. 6, p. 1801237, 2019.
[188] F. Macedo, K. Ladeira, F. Pinho, et al., “Bone metastases: An
overview,” Oncol. Rev., vol. 11, p. 321, 2017.
[189] Y. A. Nakamura, S. Okuyama, A. Furusawa, et al., “Near-infrared
photoimmunotherapy through bone,” Canc. Sci., vol. 110,
pp. 3689–3694, 2019.

Supplementary Material: The online version of this article offers supplementary material (https://doi.org/10.1515/nanoph-2021-0119).