bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Postablation Modulation after Single High-Dose Radiation Therapy Improves Tumor Control via Enhanced Immunomodulation
Authors: Savage Talicia , Pandey Sanjay , Guha Chandan
Published: April 2023

AbstractPurpose:
Radiotherapy (RT) is frequently used for local control of solid tumors using equal dose per fraction. Recently, single high-dose radiation has been used for ablation of solid tumors. In this report, we provide a novel immunological basis for radiation dose fractionation consisting of a single high-dose radiotherapy, followed by postablation modulation (PAM) with four daily low-dose fractions (22 Gy + 0.5 Gy × 4) to reprogram the tumor microenvironment by diminishing immune suppression, enabling infiltration of effector cells and increasing efficacy of tumor control.
Experimental Design:
Palpable 3LL and 4T1 tumors in C57Bl/6 and Balb/c mice were irradiated with the Small-Animal Radiation Research Platform irradiator, and tumor growth and survival were monitored. Immunomodulation of tumor and immune cells in vitro and in vivo characterization of tumor-infiltrating immune effector cells were performed by FACS. For systemic application of PAM-RT, whole-lung irradiation was administered in 4T1-bearing Balb/c mice.
Results:
We report significant tumor growth delays and increased survival in 3LL tumor–bearing mice with PAM. Primary tumor PAM-RT increased infiltration of immune effector cells and decreased Treg in irradiated tumors and secondary lymphoid organs. In a model of murine metastatic breast cancer (4T1), we demonstrated that systemic PAM-RT to the whole lung, 12 days after primary tumor ablative radiotherapy, increased survival with suppression of pulmonary metastases.
Conclusions:
We provide a novel immunologic basis for radiation dose fractionation consisting of a single high dose of radiotherapy followed by daily low-dose PAM-RT fractionation to improve the immunogenic potential of ablative radiotherapy.
Data from Exploitation of CD133 for the Targeted Imaging of Lethal Prostate Cancer
Authors: Glumac Paige M. , Gallant Joseph P. , Shapovalova Mariya , Li Yingming , Murugan Paari , Gupta Shilpa , Coleman Ilsa M. , Nelson Peter S. , Dehm Scott M. , LeBeau Aaron M.
Published: April 2023

AbstractPurpose:
Aggressive variant prostate cancer (AVPC) is a nonandrogen receptor–driven form of disease that arises in men in whom standard-of-care therapies have failed. Therapeutic options for AVPC are limited, and the development of novel therapeutics is significantly hindered by the inability to accurately quantify patient response to therapy by imaging. Imaging modalities that accurately and sensitively detect the bone and visceral metastases associated with AVPC do not exist.
Experimental Design:
This study investigated the transmembrane protein CD133 as a targetable cell surface antigen in AVPC. We evaluated the expression of CD133 by microarray and IHC analysis. The imaging potential of the CD133-targeted IgG (HA10 IgG) was evaluated in preclinical prostate cancer models using two different imaging modalities: near-infrared and PET imaging.
Results:
Evaluation of the patient data demonstrated that CD133 is overexpressed in a specific phenotype of AVPC that is androgen receptor indifferent and neuroendocrine differentiated. In addition, HA10 IgG was selective for CD133-expressing tumors in all preclinical imaging studies. PET imaging with [89Zr]Zr-HA10 IgG revealed a mean %ID/g of 24.30 ± 3.19 in CD133-positive metastatic lesions as compared with 11.82 ± 0.57 in CD133-negative lesions after 72 hours (P = 0.0069). Ex vivo biodistribution showed similar trends as signals were increased by nearly 3-fold in CD133-positive tumors (P < 0.0001).
Conclusions:
To our knowledge, this is the first study to define CD133 as a targetable marker of AVPC. Similarly, we have developed a novel imaging agent, which is selective for CD133-expressing tumors, resulting in a noninvasive PET imaging approach to more effectively detect and monitor AVPC.
Data from Targeting EZH2 Enhances Antigen Presentation, Antitumor Immunity, and Circumvents Anti–PD-1 Resistance in Head and Neck Cancer
Authors: Zhou Liye , Mudianto Tenny , Ma Xiaojing , Riley Rachel , Uppaluri Ravindra
Published: April 2023

AbstractPurpose:
Anti–programmed death-1 (PD-1) receptor–based therapeutics improve survival in patients with recurrent head and neck squamous cell carcinoma (HNSCC), but many do not benefit due to a low response rate. Herein, we identified EZH2 as a therapeutic target that enhanced tumor cell antigen presentation and subsequently sensitized resistant tumors to anti–PD-1 therapy.
Experimental Design:
EZH2 regulation of antigen presentation was defined using EZH2 inhibitors (GSK126 and EPZ6438) in human and mouse HNSCC cell lines. Mechanistic dissection of EZH2 in regulation of antigen presentation was investigated using flow cytometry, qRT-PCR, ELISA, and chromatin-immunoprecipitation assays. EZH2-deficient cell lines were generated using CRISPR-CAS9. GSK126 and anti–PD‐1–blocking antibody were used in testing combinatorial therapy in vivo.
Results:
EZH2 expression was negatively correlated with antigen-processing machinery pathway components in HNSCC data sets in The Cancer Genome Atlas. EZH2 inhibition resulted in significant upregulation of MHC class I expression in human and mouse human papillomavirus–negative HNSCC lines in vitro and in mouse models in vivo. Enhanced antigen presentation on the tumor cells by EZH2 inhibitors or CRISPR–mediated EZH2 deficiency increased antigen-specific CD8+ T-cell proliferation, IFNγ production, and tumor cell cytotoxicity. Mechanistically, EZH2 inhibition reduced the histone H3K27me3 modification on the β-2-microglobulin promoter. Finally, in an anti–PD-1–resistant model of HNSCC, tumor growth was suppressed with combination therapy.
Conclusions:
Our results demonstrated that targeting EZH2 enhanced antigen presentation and was able to circumvent anti–PD-1 resistance. Thus, combining EZH2 targeting with anti–PD-1 may increase therapeutic susceptibility in HNSCC.
Data from Inactivating NF1 Mutations Are Enriched in Advanced Breast Cancer and Contribute to Endocrine Therapy Resistance
Authors: Pearson Alex , Proszek Paula , Pascual Javier , Fribbens Charlotte , Shamsher Monee K. , Kingston Belinda , O'Leary Ben , Herrera-Abreu Maria T. , Cutts Rosalind J. , Garcia-Murillas Isaac , Bye Hannah , Walker Brian A. , Gonzalez De Castro David , Yuan Lina , Jamal Sabri , Hubank Mike , Lopez-Knowles Elena , Schuster Eugene F. , Dowsett Mitch , Osin Peter , Nerurkar Ashutosh , Parton Marina , Okines Alicia F.C. , Johnston Stephen R.D. , Ring Alistair , Turner Nicholas C.
Published: April 2023

AbstractPurpose:
Advanced breast cancer (ABC) has not been subjected to the same degree of molecular scrutiny as early primary cancer. Breast cancer evolves with time and under the selective pressure of treatment, with the potential to acquire mutations with resistance to treatment and disease progression. To identify potentially targetable mutations in advanced breast cancer, we performed prospective molecular characterization of a cohort of patients with ABC.
Experimental Design:
Biopsies from patients with advanced breast cancer were sequenced with a 41 genes targeted panel in the ABC Biopsy (ABC-Bio) study. Blood samples were collected at disease progression for circulating tumor DNA (ctDNA) analysis, along with matched primary tumor to assess for acquisition in ABC in a subset of patients.
Results:
We sequenced 210 ABC samples, demonstrating enrichment compared with primary disease for potentially targetable mutations in HER2 (in 6.19% of samples), AKT1 (7.14%), and NF1 (8.10%). Of these enriched mutations, we show that NF1 mutations were frequently acquired in ABC, not present in the original primary disease. In ER-positive cancer cell line models, loss of NF1 resulted in endocrine therapy resistance, through both ER-dependent and -independent mechanisms. NF1 loss promoted ER-independent cyclin D1 expression, which could be therapeutically targeted with CDK4/6 inhibitors in vitro. Patients with NF1 mutations detected in baseline circulating tumor DNA had a good outcome on the CDK4/6 inhibitor palbociclib and fulvestrant.
Conclusions:
Our research identifies multiple therapeutic opportunities for advanced breast cancer and identifies the previously underappreciated acquisition of NF1 mutations.
Data from FLASH Irradiation Spares Lung Progenitor Cells and Limits the Incidence of Radio-induced Senescence
Authors: Fouillade Charles , Curras-Alonso Sandra , Giuranno Lorena , Quelennec Eddy , Heinrich Sophie , Bonnet-Boissinot Sarah , Beddok Arnaud , Leboucher Sophie , Karakurt Hamza Umut , Bohec Mylène , Baulande Sylvain , Vooijs Marc , Verrelle Pierre , Dutreix Marie , Londoño-Vallejo Arturo , Favaudon Vincent
Published: April 2023

AbstractPurpose:
One of the main limitations to anticancer radiotherapy lies in irreversible damage to healthy tissues located within the radiation field. “FLASH” irradiation at very high dose-rate is a new treatment modality that has been reported to specifically spare normal tissue from late radiation-induced toxicity in animal models and therefore could be a promising strategy to reduce treatment toxicity.
Experimental Design:
Lung responses to FLASH irradiation were investigated by qPCR, single-cell RNA sequencing (sc-RNA-Seq), and histologic methods during the acute wound healing phase as well as at late stages using C57BL/6J wild-type and Terc−/− mice exposed to bilateral thorax irradiation as well as human lung cells grown in vitro.
Results:
In vitro studies gave evidence of a reduced level of DNA damage and induced lethality at the advantage of FLASH. In mouse lung, sc-RNA-seq and the monitoring of proliferating cells revealed that FLASH minimized the induction of proinflammatory genes and reduced the proliferation of progenitor cells after injury. At late stages, FLASH-irradiated lungs presented less persistent DNA damage and senescent cells than after CONV exposure, suggesting a higher potential for lung regeneration with FLASH. Consistent with this hypothesis, the beneficial effect of FLASH was lost in Terc−/− mice harboring critically short telomeres and lack of telomerase activity.
Conclusions:
The results suggest that, compared with conventional radiotherapy, FLASH minimizes DNA damage in normal cells, spares lung progenitor cells from excessive damage, and reduces the risk of replicative senescence.
Data from Comprehensive Transcriptome Profiling of Cryptic CBFA2T3–GLIS2 Fusion–Positive AML Defines Novel Therapeutic Options: A COG and TARGET Pediatric AML Study
Authors: Smith Jenny L. , Ries Rhonda E. , Hylkema Tiffany , Alonzo Todd A. , Gerbing Robert B. , Santaguida Marianne T. , Eidenschink Brodersen Lisa , Pardo Laura , Cummings Carrie L. , Loeb Keith R. , Le Quy , Imren Suzan , Leonti Amanda R. , Gamis Alan S. , Aplenc Richard , Kolb E. Anders , Farrar Jason E. , Triche Timothy J. , Nguyen Cu , Meerzaman Daoud , Loken Michael R. , Oehler Vivian G. , Bolouri Hamid , Meshinchi Soheil
Published: April 2023

AbstractPurpose:
A cryptic inv(16)(p13.3q24.3) encoding the CBFA2T3–GLIS2 fusion is associated with poor outcome in infants with acute megakaryocytic leukemia. We aimed to broaden our understanding of the pathogenesis of this fusion through transcriptome profiling.
Experimental Design:
Available RNA from children and young adults with de novo acute myeloid leukemia (AML; N = 1,049) underwent transcriptome sequencing (mRNA and miRNA). Transcriptome profiles for those with the CBFA2T3–GLIS2 fusion (N = 24) and without (N = 1,025) were contrasted to define fusion-specific miRNAs, genes, and pathways. Clinical annotations defined distinct fusion-associated disease characteristics and outcomes.
Results:
The CBFA2T3–GLIS2 fusion was restricted to infants <3 years old (P < 0.001), and the presence of this fusion was highly associated with adverse outcome (P < 0.001) across all morphologic classifications. Further, there was a striking paucity of recurrent cooperating mutations, and transduction of cord blood stem cells with this fusion was sufficient for malignant transformation. CBFA2T3–GLIS2 positive cases displayed marked upregulation of genes with cell membrane/extracellular matrix localization potential, including NCAM1 and GABRE. Additionally, miRNA profiling revealed significant overexpression of mature miR-224 and miR-452, which are intronic miRNAs transcribed from the GABRE locus. Gene-set enrichment identified dysregulated Hippo, TGFβ, and hedgehog signaling, as well as NCAM1 (CD56) interaction pathways. Therapeutic targeting of fusion-positive leukemic cells with CD56-directed antibody–drug conjugate caused significant cytotoxicity in leukemic blasts.
Conclusions:
The CBFA2T3–GLIS2 fusion defines a highly refractory entity limited to infants that appears to be sufficient for malignant transformation. Transcriptome profiling elucidated several highly targetable genes and pathways, including the identification of CD56, providing a highly plausible target for therapeutic intervention.
Data from A Phase II, Prospective, Randomized, Multicenter, Open-Label Study of GX-188E, an HPV DNA Vaccine, in Patients with Cervical Intraepithelial Neoplasia 3
Authors: Choi Youn Jin , Hur Soo Young , Kim Tae-Jin , Hong Sung Ran , Lee Jae Kwan , Cho Chi-Heum , Park Ki Seok , Woo Jung Won , Sung Young Chul , Suh You Suk , Park Jong Sup
Published: April 2023

AbstractPurpose:
To determine the efficacy of the therapeutic DNA vaccine GX-188E for inducing regression of cervical intraepithelial neoplasia (CIN) 3.
Patients and Methods:
We conducted a prospective, randomized, multicenter, open-label, phase II clinical trial of GX-188E in CIN3 patients positive for human papillomavirus (HPV) type 16/18. The primary endpoint was to determine the histopathologic regression to ≤CIN1 at visit seven (V7; 20 weeks after the first GX-188E injection), and an extension study was pursued until visit 8 (V8; 36 weeks after the first GX-188E injection). HPV-sequencing analysis and an ex vivo IFNγ ELISpot assay were performed using the collected cervical biopsy and blood samples from patients.
Results:
In total, 72 patients were enrolled and underwent randomization. Of them, 64 patients were included in per-protocol analysis (V7) and 52 in extension analysis (V8). Our data showed 52% (33/64) of patients at V7 and 67% (35/52) of patients at V8 presented histopathologic regression after receiving the GX-188E injection. We found that 73% (V7) and 77% (V8) of the patients with histologic regression showed HPV clearance. HPV clearance and histopathologic regression were significantly associated at V7 and at V8. Compared with the measurements at V1 (baseline), the patients at V8 with HPV clearance showed significantly higher fold changes in their IFNγ ELISpot responses compared with those without HPV clearance. The HPV sequence analysis revealed that the HPV type 16 E6/E7 variants D25E, V83L, and N29S were inversely associated with histopathologic regression at V8.
Conclusions:
GX-188E is an effective therapeutic vaccine against a cohort containing only CIN3 patients.
Data from Epigenetic Silencing Affects l-Asparaginase Sensitivity and Predicts Outcome in T-ALL
Authors: Touzart Aurore , Lengliné Etienne , Latiri Mehdi , Belhocine Mohamed , Smith Charlotte , Thomas Xavier , Spicuglia Salvatore , Puthier Denis , Pflumio Françoise , Leguay Thibaut , Graux Carlos , Chalandon Yves , Huguet Françoise , Leprêtre Stéphane , Ifrah Norbert , Dombret Hervé , Macintyre Elizabeth , Hunault Mathilde , Boissel Nicolas , Asnafi Vahid
Published: April 2023

AbstractPurpose:
Biological explanation for discrepancies in patient-related response to chemotherapy depending on the underlying oncogenic events is a promising research area. TLX1- or TLX3-deregulated T-cell acute lymphoblastic leukemias (T-ALL; TLX1/3+) share an immature cortical phenotype and similar transcriptional signatures. However, their prognostic impacts differ, and inconsistent clinical outcome has been reported for TLX3. We therefore hypothesized that the overlapping transcriptional profiles of TLX1+ and TLX3+ T-ALLs would allow identification of candidate genes, which might determine their distinct clinical outcomes.
Experimental Design:
We compared TLX1+ and TLX3+ adult T-ALL outcome in the successive French national LALA-94 and GRAALL-2003/2005 multicentric trials and analyzed transcriptomic data to identify differentially expressed genes. Epigenetic regulation of asparagine synthetase (ASNS) and in vitro l-asparaginase sensitivity were evaluated for T-ALL cell lines and primary samples.
Results:
We show that TLX1+ patients expressed low levels of ASNS when compared with TLX3+ and TLX-negative patients, due to epigenetic silencing of ASNS by both DNA methylation and a decrease of active histone marks. Promoter methylation of the ASNS gene correlated with l-asparaginase sensitivity in both T-ALL cell lines and patient-derived xenografts. Finally, ASNS promoter methylation was an independent prognostic factor for both event-free survival [HR, 0.42; 95% confidence interval (CI), 0.24–0.71; P = 0.001] and overall survival (HR, 0.40; 95% CI, 0.23–0.70; P = 0.02) in 160 GRAALL-2003/2005 T-ALL patients and also in an independent series of 47 LL03-treated T lymphoblastic lymphomas (P = 0.012).
Conclusions:
We conclude that ASNS methylation status at diagnosis may allow individual adaptation of l-asparaginase dose.
Data from Overall Survival in Malignant Glioma Is Significantly Prolonged by Neurosurgical Delivery of Etoposide and Temozolomide from a Thermo-Responsive Biodegradable Paste
Authors: Smith Stuart J. , Tyler Betty M. , Gould Toby , Veal Gareth J. , Gorelick Noah , Rowlinson Jonathan , Serra Riccardo , Ritchie Alison , Berry Phillip , Otto Annette , Choi John , Skuli Nicolas , Estevez-Cebrero Maria , Shakesheff Kevin M. , Brem Henry , Grundy Richard G. , Rahman Ruman
Published: April 2023

AbstractPurpose:
High-grade glioma (HGG) treatment is limited by the inability of otherwise potentially efficacious drugs to penetrate the blood–brain barrier. We evaluate the unique intracavity delivery mode and translational potential of a blend of poly(DL-lactic acid-co-glycolic acid; PLGA) and poly(ethylene glycol; PEG) paste combining temozolomide and etoposide to treat surgically resected HGG.
Experimental Design:
To prolong stability of temozolomide prodrug, combined in vitro drug release was quantitatively assessed from low pH–based PLGA/PEG using advanced analytic methods. In vitro cytotoxicity was measured against a panel of HGG cell lines and patient-derived cultures using metabolic assays. In vivo safety and efficacy was evaluated using orthotopic 9L gliosarcoma allografts, previously utilized preclinically to develop Gliadel.
Results:
Combined etoposide and temozolomide in vitro release (22 and 7 days, respectively) was achieved from a lactic acid–based PLGA/PEG paste, used to enhance stability of temozolomide prodrug. HGG cells from central-enhanced regions were more sensitive to each compound relative to primary lines derived from the HGG-invasive margin. Both drugs retained cytotoxic capability upon release from PLGA/PEG. In vivo studies revealed a significant overall survival benefit in postsurgery 9L orthotopic gliosarcomas, treated with intracavity delivered PLGA/PEG/temozolomide/etoposide and enhanced with adjuvant radiotherapy. Long-term survivorship was observed in over half the animals with histologic confirmation of disease-free brain.
Conclusions:
The significant survival benefit of intracavity chemotherapy demonstrates clinical applicability of PLGA/PEG paste-mediated delivery of temozolomide and etoposide adjuvant to radiotherapy. PLGA/PEG paste offers a future platform for combination delivery of molecular targeted compounds.
Data from Potent Cell-Cycle Inhibition and Upregulation of Immune Response with Abemaciclib and Anastrozole in neoMONARCH, Phase II Neoadjuvant Study in HR+/HER2− Breast Cancer
Authors: Hurvitz Sara A. , Martin Miguel , Press Michael F. , Chan David , Fernandez-Abad María , Petru Edgar , Rostorfer Regan , Guarneri Valentina , Huang Chiun-Sheng , Barriga Susana , Wijayawardana Sameera , Brahmachary Manisha , Ebert Philip J. , Hossain Anwar , Liu Jiangang , Abel Adam , Aggarwal Amit , Jansen Valerie M. , Slamon Dennis J.
Published: April 2023

AbstractPurpose:
neoMONARCH assessed the biological effects of abemaciclib in combination with anastrozole in the neoadjuvant setting.
Patients and Methods:
Postmenopausal women with stage I–IIIB HR+/HER2− breast cancer were randomized to a 2-week lead-in of abemaciclib, anastrozole, or abemaciclib plus anastrozole followed by 14 weeks of the combination. The primary objective evaluated change in Ki67 from baseline to 2 weeks of treatment. Additional objectives included clinical, radiologic, and pathologic responses, safety, as well as gene expression changes related to cell proliferation and immune response.
Results:
Abemaciclib, alone or in combination with anastrozole, achieved a significant decrease in Ki67 expression and led to potent cell-cycle arrest after 2 weeks of treatment compared with anastrozole alone. More patients in the abemaciclib-containing arms versus anastrozole alone achieved complete cell-cycle arrest (58%/68% vs. 14%, P < 0.001). At the end of treatment, following 2 weeks lead-in and 14 weeks of combination therapy, 46% of intent-to-treat patients achieved a radiologic response, with pathologic complete response observed in 4%. The most common all-grade adverse events were diarrhea (62%), constipation (44%), and nausea (42%). Abemaciclib, anastrozole, and the combination inhibited cell-cycle processes and estrogen signaling; however, combination therapy resulted in increased cytokine signaling and adaptive immune response indicative of enhanced antigen presentation and activated T-cell phenotypes.
Conclusions:
Abemaciclib plus anastrozole demonstrated biological and clinical activity with generally manageable toxicities in patients with HR+/HER2− early breast cancer. Abemaciclib led to potent cell-cycle arrest, and in combination with anastrozole, enhanced immune activation.
Data from Integrated Molecular Analysis of Undifferentiated Uterine Sarcomas Reveals Clinically Relevant Molecular Subtypes
Authors: Binzer-Panchal Amrei , Hardell Elin , Viklund Björn , Ghaderi Mehran , Bosse Tjalling , Nucci Marisa R. , Lee Cheng-Han , Hollfelder Nina , Corcoran Pádraic , Gonzalez-Molina Jordi , Moyano-Galceran Lidia , Bell Debra A. , Schoolmeester John K. , Måsbäck Anna , Kristensen Gunnar B. , Davidson Ben , Lehti Kaisa , Isaksson Anders , Carlson Joseph W.
Published: April 2023

AbstractPurpose:
Undifferentiated uterine sarcomas (UUS) are rare, extremely deadly, sarcomas with no effective treatment. The goal of this study was to identify novel intrinsic molecular UUS subtypes using integrated clinical, histopathologic, and molecular evaluation of a large, fully annotated, patient cohort.
Experimental Design:
Fifty cases of UUS with full clinicopathologic annotation were analyzed for gene expression (n = 50), copy-number variation (CNV, n = 40), cell morphometry (n = 39), and protein expression (n = 22). Gene ontology and network enrichment analysis were used to relate over- and underexpressed genes to pathways and further to clinicopathologic and phenotypic findings.
Results:
Gene expression identified four distinct groups of tumors, which varied in their clinicopathologic parameters. Gene ontology analysis revealed differential activation of pathways related to genital tract development, extracellular matrix (ECM), muscle function, and proliferation. A multivariable, adjusted Cox proportional hazard model demonstrated that RNA group, mitotic index, and hormone receptor expression influence patient overall survival (OS). CNV arrays revealed characteristic chromosomal changes for each group. Morphometry demonstrated that the ECM group, the most aggressive, exhibited a decreased cell density and increased nuclear area. A cell density cutoff of 4,300 tumor cells per mm2 could separate ECM tumors from the remaining cases with a sensitivity of 83% and a specificity of 94%. IHC staining of MMP-14, Collagens 1 and 6, and Fibronectin proteins revealed differential expression of these ECM-related proteins, identifying potential new biomarkers for this aggressive sarcoma subgroup.
Conclusions:
Molecular evaluation of UUS provides novel insights into the biology, prognosis, phenotype, and possible treatment of these tumors.
Data from Pilot Trial AMC-063: Safety and Efficacy of Bortezomib in AIDS-associated Kaposi Sarcoma
Authors: Reid Erin G. , Suazo Adrienne , Lensing Shelly Y. , Dittmer Dirk P. , Ambinder Richard F. , Maldarelli Frank , Gorelick Robert J. , Aboulafia David , Mitsuyasu Ronald , Dickson Mark A. , Wachsman William
Published: April 2023

AbstractPurpose:
AIDS-related Kaposi sarcoma is often incompletely controlled, requiring serial therapies. Kaposi sarcoma herpesvirus (KSHV) induces transformation of endothelial cells, where it resides in a predominately latent state. We hypothesized proteasome inhibition would have direct antitumor activity, induce lytic activation of KSHV, and inhibit HIV infectivity, improving control of both Kaposi sarcoma and HIV. The primary objective was determining the MTD of bortezomib in AIDS-Kaposi sarcoma. Secondary objectives included estimating the impact of bortezomib on Kaposi sarcoma response, KSHV plasma DNA copy number (PDCN), and HIV viral loads (VL).
Patients and Methods:
A 3+3 dose escalation design was employed evaluating four dose levels of bortezomib (0.75, 1, 1.2, or 1.6 mg/m2) administered intravenously on days 1, 8, and 15 of 28-day cycles in patients with relapsed/refractory (r/r) AIDS-Kaposi sarcoma taking antiretroviral therapy.
Results:
Seventeen patients enrolled. No dose-limiting toxicities occurred and the MTD was not reached. The most common adverse events included diarrhea, fatigue and nausea. Among 15 evaluable patients, partial response (PR) occurred in nine (60%), with a PR rate of 83% in the 1.6 mg/m2 cohort; the remainder had stable disease (SD). Median time to response was 2.1 months. Median change in KSHV PDCN was significantly different between those with PR versus SD. During cycle 1, seven of 11 evaluable patients had decreases in HIV VL.
Conclusions:
Bortezomib is well-tolerated and active in AIDS-Kaposi sarcoma. The 60% PR rate is notable given the dose-finding nature of the study in a r/r population. Changes in KSHV PDCN and HIV VL trended as hypothesized.
Data from Prognostic Value of Residual Disease after Neoadjuvant Therapy in HER2-Positive Breast Cancer Evaluated by Residual Cancer Burden, Neoadjuvant Response Index, and Neo-Bioscore
Authors: Steenbruggen Tessa G. , van Seijen Maartje , Janssen Liselore M. , van Ramshorst Mette S. , van Werkhoven Erik , Vrancken Peeters Marie-Jeanne T.D.F. , Wesseling Jelle , Lips Esther H. , Sonke Gabe S.
Published: April 2023

AbstractPurpose:
In breast cancer, pathologic complete response (pCR) to neoadjuvant systemic therapy (NST) is associated with favorable long-term outcome. Trastuzumab emtansine as additional adjuvant therapy improves recurrence-free survival of patients with HER2-positive breast cancer without pCR, but it is uncertain whether all patients without pCR need additional therapy. We evaluated the prognostic value of residual disease after trastuzumab-based NST in patients with HER2-positive breast cancer using Residual Cancer Burden (RCB), Neoadjuvant Response Index (NRI), and Neo-Bioscore.
Experimental Design:
We included patients with stage II or III HER2-positive breast cancer treated with trastuzumab-based NST and surgery at The Netherlands Cancer Institute between 2004 and 2016. RCB, NRI, and Neo-Bioscore were determined. Primary endpoint was 5-year recurrence-free interval (RFI). A 3% difference compared with the pCR group was considered acceptable as noninferiority margin on the 5-year RFI estimate, based on a proportional hazards model, and its lower 95% confidence boundary.
Results:
A total of 283 women were included. Median follow-up was 67 months (interquartile range 44–100). A total of 157 patients (56%) with pCR (breast and axilla) had a 5-year RFI of 92% (95% CI, 88–97); patients without pCR had a 5-year RFI of 80% (95% CI, 72–88). Patients with an RCB = 1 (N = 40, 15%), an NRI score between 0.75 and 0.99 (N = 30, 11%), or a Neo-Bioscore of 0 to 1 (without pCR; N = 28, 11%) have a 5-year RFI that falls within a predefined noninferiority margin of 3% compared with patients with pCR.
Conclusions:
The RCB, NRI, and Neo-Bioscore can identify patients with HER2-positive breast cancer with minimal residual disease (i.e., RCB = 1, NRI ≥ 0.75, or Neo-Bioscore = 0–1) after NST who have similar 5-year RFI compared with patients with pCR.
Data from Human Breast Cancer Xenograft Model Implicates Peroxisome Proliferator–activated Receptor Signaling as Driver of Cancer-induced Muscle Fatigue
Authors: Wilson Hannah E. , Rhodes Kacey K. , Rodriguez Daniel , Chahal Ikttesh , Stanton David A. , Bohlen Joseph , Davis Mary , Infante Aniello M. , Hazard-Jenkins Hannah , Klinke David J. , Pugacheva Elena N. , Pistilli Emidio E.
Published: April 2023

AbstractPurpose:
This study tested the hypothesis that a patient-derived orthotopic xenograft (PDOX) model would recapitulate the common clinical phenomenon of breast cancer–induced skeletal muscle (SkM) fatigue in the absence of muscle wasting. This study additionally sought to identify drivers of this condition to facilitate the development of therapeutic agents for patients with breast cancer experiencing muscle fatigue.
Experimental Design:
Eight female BC-PDOX–bearing mice were produced via transplantation of tumor tissue from 8 female patients with breast cancer. Individual hind limb muscles from BC-PDOX mice were isolated at euthanasia for RNA-sequencing, gene and protein analyses, and an ex vivo muscle contraction protocol to quantify tumor-induced aberrations in SkM function. Differentially expressed genes (DEG) in the BC-PDOX mice relative to control mice were identified using DESeq2, and multiple bioinformatics platforms were employed to contextualize the DEGs.
Results:
We found that SkM from BC-PDOX–bearing mice showed greater fatigability than control mice, despite no differences in absolute muscle mass. PPAR, mTOR, IL6, IL1, and several other signaling pathways were implicated in the transcriptional changes observed in the BC-PDOX SkM. Moreover, 3 independent in silico analyses identified PPAR signaling as highly dysregulated in the SkM of both BC-PDOX–bearing mice and human patients with early-stage nonmetastatic breast cancer.
Conclusions:
Collectively, these data demonstrate that the BC-PDOX model recapitulates the expected breast cancer–induced SkM fatigue and further identify aberrant PPAR signaling as an integral factor in the pathology of this condition.
Data from Whole-Slide Image Analysis Reveals Quantitative Landscape of Tumor–Immune Microenvironment in Colorectal Cancers
Authors: Yoo Seung-Yeon , Park Hye Eun , Kim Jung Ho , Wen Xianyu , Jeong Seorin , Cho Nam-Yun , Gwon Hwang Gwan , Kim Kwangsoo , Lee Hye Seung , Jeong Seung-Yong , Park Kyu Joo , Han Sae-Won , Kim Tae-You , Bae Jeong Mo , Kang Gyeong Hoon
Published: April 2023

AbstractPurpose:
Despite the well-known prognostic value of the tumor–immune microenvironment (TIME) in colorectal cancers, objective and readily applicable methods for quantifying tumor-infiltrating lymphocytes (TIL) and the tumor–stroma ratio (TSR) are not yet available.
Experimental Design:
We established an open-source software-based analytic pipeline for quantifying TILs and the TSR from whole-slide images obtained after CD3 and CD8 IHC staining. Using a random forest classifier, the method separately quantified intraepithelial TILs (iTIL) and stromal TILs (sTIL). We applied this method to discovery and validation cohorts of 578 and 283 stage III or high-risk stage II colorectal cancers patients, respectively, who were subjected to curative surgical resection and oxlaliplatin-based adjuvant chemotherapy.
Results:
Automatic quantification of iTILs and sTILs showed a moderate concordance with that obtained after visual inspection by a pathologist. The K-means–based consensus clustering of 197 TIME parameters that showed robustness against interobserver variations caused colorectal cancers to be grouped into five distinctive subgroups, reminiscent of those for consensus molecular subtypes (CMS1-4 and mixed/intermediate group). In accordance with the original CMS report, the CMS4-like subgroup (cluster 4) was significantly associated with a worse 5-year relapse-free survival and proved to be an independent prognostic factor. The clinicopathologic and prognostic features of the TIME subgroups have been validated in an independent validation cohort.
Conclusions:
Machine-learning–based image analysis can be useful for extracting quantitative information about the TIME, using whole-slide histopathologic images. This information can classify colorectal cancers into clinicopathologically relevant subgroups without performing a molecular analysis of the tumors.
Data from Molecular Subtype Not Immune Response Drives Outcomes in Endometrial Carcinoma
Authors: Talhouk Aline , Derocher Heather , Schmidt Pascal , Leung Samuel , Milne Katy , Gilks C. Blake , Anglesio Michael S. , Nelson Brad H. , McAlpine Jessica N.
Published: April 2023

AbstractPurpose:
Tumors with high mutation load are thought to engender stronger immune responses, which in turn promote prolonged patient survival. To investigate this, we assessed tumor-infiltrating lymphocytes (TILs) and immunosuppressive factors across the 4 molecular subtypes of endometrial cancer, which have characteristic mutation rates ranging from low to ultra-high.
Experimental Design:
A total of 460 endometrial cancers were stratified by ProMisE (Proactive Molecular Risk Classifier in Endometrial cancer) into 4 molecular subtypes: mismatch repair-deficient (MMRd), POLE mutant (POLE), p53 abnormal (p53abn), and p53 wild-type (p53wt). Immune markers (CD3, CD8, CD79a, CD138, PD-1, PD-L1, FoxP3, IDO-1) were quantified by multiplex IHC and tested for associations with ProMisE subtype, survival, and other clinicopathologic parameters.
Results:
Two major TIL patterns were observed. TILhigh tumors harbored dense T- and B-lineage infiltrates and multiple immunosuppressive features and were common in molecular subtypes associated with high mutation load (MMRd and POLE); however, equally strong responses were seen in significant numbers of p53abn and p53wt tumors, which have characteristically low mutation loads. TILlow tumors were generally devoid of immunologic features and were more prevalent in p53abn and p53wt endometrial cancers, yet were also seen in MMRd and POLE subtypes. In multivariable models involving ProMisE subtype, T-cell markers, and TIL clusters, only ProMisE showed independent prognostic significance.
Conclusions:
Immune response correlates with endometrial cancer molecular subtype but does not carry independent prognostic significance. Profound variation in immune response is seen across and within endometrial cancer molecular subtypes, suggesting that assessment of immune response rather than molecular subtype may better predict response to immunotherapy.

See related commentary by Mullen and Mutch, p. 2366
Data from Diverse Resistance Mechanisms to the Third-Generation ALK Inhibitor Lorlatinib in ALK-Rearranged Lung Cancer
Authors: Recondo Gonzalo , Mezquita Laura , Facchinetti Francesco , Planchard David , Gazzah Anas , Bigot Ludovic , Rizvi Ahsan Z. , Frias Rosa L. , Thiery Jean Paul , Scoazec Jean-Yves , Sourisseau Tony , Howarth Karen , Deas Olivier , Samofalova Dariia , Galissant Justine , Tesson Pauline , Braye Floriane , Naltet Charles , Lavaud Pernelle , Mahjoubi Linda , Abou Lovergne Aurélie , Vassal Gilles , Bahleda Rastilav , Hollebecque Antoine , Nicotra Claudio , Ngo-Camus Maud , Michiels Stefan , Lacroix Ludovic , Richon Catherine , Auger Nathalie , De Baere Thierry , Tselikas Lambros , Solary Eric , Angevin Eric , Eggermont Alexander M. , Andre Fabrice , Massard Christophe , Olaussen Ken A. , Soria Jean-Charles , Besse Benjamin , Friboulet Luc
Published: April 2023

AbstractPurpose:
Lorlatinib is a third-generation anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor with proven efficacy in patients with ALK-rearranged lung cancer previously treated with first- and second-generation ALK inhibitors. Beside compound mutations in the ALK kinase domain, other resistance mechanisms driving lorlatinib resistance remain unknown. We aimed to characterize the mechanisms of resistance to lorlatinib occurring in patients with ALK-rearranged lung cancer and design new therapeutic strategies in this setting.
Experimental Design:
Resistance mechanisms were investigated in 5 patients resistant to lorlatinib. Longitudinal tumor biopsies were studied using high-throughput next-generation sequencing. Patient-derived models were developed to characterize the acquired resistance mechanisms, and Ba/F3 cell mutants were generated to study the effect of novel ALK compound mutations. Drug combinatory strategies were evaluated in vitro and in vivo to overcome lorlatinib resistance.
Results:
Diverse biological mechanisms leading to lorlatinib resistance were identified. Epithelial–mesenchymal transition (EMT) mediated resistance in two patient-derived cell lines and was susceptible to dual SRC and ALK inhibition. We characterized three ALK kinase domain compound mutations occurring in patients, L1196M/D1203N, F1174L/G1202R, and C1156Y/G1269A, with differential susceptibility to ALK inhibition by lorlatinib. We identified a novel bypass mechanism of resistance caused by NF2 loss-of-function mutations, conferring sensitivity to treatment with mTOR inhibitors.
Conclusions:
This study shows that mechanisms of resistance to lorlatinib are diverse and complex, requiring new therapeutic strategies to tailor treatment upon disease progression.
Data from Identification of Hypermutation and Defective Mismatch Repair in ctDNA from Metastatic Prostate Cancer
Authors: Ritch Elie , Fu Simon Y.F. , Herberts Cameron , Wang Gang , Warner Evan W. , Schönlau Elena , Taavitsainen Sinja , Murtha Andrew J. , Vandekerkhove Gillian , Beja Kevin , Loktionova Yulia , Khalaf Daniel , Fazli Ladan , Kushnir Igal , Ferrario Cristiano , Hotte Sebastien , Annala Matti , Chi Kim N. , Wyatt Alexander W.
Published: April 2023

AbstractPurpose:
DNA mismatch repair defects (MMRd) and tumor hypermutation are rare and under-characterized in metastatic prostate cancer (mPC). Furthermore, because hypermutated MMRd prostate cancers can respond to immune checkpoint inhibitors, there is an urgent need for practical detection tools.
Experimental Design:
We analyzed plasma cell-free DNA-targeted sequencing data from 433 patients with mPC with circulating tumor DNA (ctDNA) purity ≥2%. Samples with somatic hypermutation were subjected to 185 × whole-exome sequencing and capture of mismatch repair gene introns. Archival tissue was analyzed with targeted sequencing and IHC.
Results:
Sixteen patients (3.7%) had somatic hypermutation with MMRd etiology, evidenced by deleterious alterations in MSH2, MSH6, or MLH1, microsatellite instability, and characteristic trinucleotide signatures. ctDNA was concordant with mismatch repair protein IHC and DNA sequencing of tumor tissue. Tumor suppressors such as PTEN, RB1, and TP53 were inactivated by mutation rather than copy-number loss. Hotspot mutations in oncogenes such as AKT1, PIK3CA, and CTNNB1 were common, and the androgen receptor (AR)-ligand binding domain was mutated in 9 of 16 patients. We observed high intrapatient clonal diversity, evidenced by subclonal driver mutations and shifts in mutation allele frequency over time. Patients with hypermutation and MMRd etiology in ctDNA had a poor response to AR inhibition and inferior survival compared with a control cohort.
Conclusions:
Hypermutated MMRd mPC is associated with oncogene activation and subclonal diversity, which may contribute to a clinically aggressive disposition in selected patients. In patients with detectable ctDNA, cell-free DNA sequencing is a practical tool to prioritize this subtype for immunotherapy.

See related commentary by Schweizer and Yu, p. 981
Data from Harnessing Androgen Receptor Pathway Activation for Targeted Alpha Particle Radioimmunotherapy of Breast Cancer
Authors: Thorek Daniel L.J. , Ku Anson T. , Mitsiades Nicholas , Veach Darren , Watson Philip A. , Metha Dipti , Strand Sven-Erik , Sharma Sai Kiran , Lewis Jason S. , Abou Diane S. , Lilja Hans G. , Larson Steven M. , McDevitt Michael R. , Ulmert David
Published: April 2023

AbstractPurpose:
The impact of androgen receptor (AR) activity in breast cancer biology is unclear. We characterized and tested a novel therapy to an AR-governed target in breast cancer.

Experimental Design: We evaluated the expression of prototypical AR gene products human kallikrein 2 (hK2) and PSA in breast cancer models. We screened 13 well-characterized breast cancer cell lines for hK2 and PSA production upon in vitro hormone stimulation by testosterone [dihydrotestosterone (DHT)]. AR-positive lines were further evaluated by exposure to estrogen (17β-Estradiol) and the synthetic progestin D-Norgestrel. We then evaluated an anti-hK2–targeted radiotherapy platform (hu11B6), labeled with alpha (α)-particle emitting Actinium-225, to specifically treat AR-expressing breast cancer xenografts under hormone stimulation.
Results:
D-Norgestrel and DHT activated the AR pathway, while 17β-Estradiol did not. Competitive binding for AR protein showed similar affinity between DHT and D-Norgestrel, indicating direct AR–ligand interaction. In vivo production of hK2 was sufficient to achieve site-specific delivery of therapeutic radionuclide to tumor tissue at >20-fold over background muscle uptake; effecting long-term local tumor control.
Conclusions:
[225Ac]hu11B6 targeted radiotherapy was potentiated by DHT and by D-Norgestrel in murine xenograft models of breast cancer. AR activity in breast cancer correlates with kallikrein-related peptidase-2 and can be activated by D-Norgestrel, a common contraceptive, and AR induction can be harnessed for hK2-targeted breast cancer α-emitter radiotherapy.
Data from Host IDO2 Gene Status Influences Tumor Progression and Radiotherapy Response in KRAS-Driven Sporadic Pancreatic Cancers
Authors: Nevler Avinoam , Muller Alexander J. , Sutanto-Ward Erika , DuHadaway James B. , Nagatomo Kei , Londin Eric , O'Hayer Kevin , Cozzitorto Joseph A. , Lavu Harish , Yeo Theresa P. , Curtis Mark , Villatoro Tatiana , Leiby Benjamin E. , Mandik-Nayak Laura , Winter Jordan M. , Yeo Charles J. , Prendergast George C. , Brody Jonathan R.
Published: April 2023

AbstractPurpose:
Heritable genetic variations can affect the inflammatory tumor microenvironment, which can ultimately affect cancer susceptibility and clinical outcomes. Recent evidence indicates that IDO2, a positive modifier in inflammatory disease models, is frequently upregulated in pancreatic ductal adenocarcinoma (PDAC). A unique feature of IDO2 in humans is the high prevalence of two inactivating single-nucleotide polymorphisms (SNP), which affords the opportunity to carry out loss-of-function studies directly in humans. In this study, we sought to address whether genetic loss of IDO2 may influence PDAC development and responsiveness to treatment.

Experimental Design: Transgenic Ido2+/+ and Ido2−/− mice in which oncogenic KRAS is activated in pancreatic epithelial cells were evaluated for PDAC. Two patient data sets (N = 200) were evaluated for the two IDO2-inactivating SNPs together with histologic, RNA expression, and clinical survival data.
Results:
PDAC development was notably decreased in the Ido2−/− mice (30% vs. 10%, P < 0.05), with a female predominance similar to the association observed for one of the human SNPs. In patients, the biallelic occurrence of either of the two IDO2-inactivating SNPs was significantly associated with markedly improved disease-free survival in response to adjuvant radiotherapy (P < 0.01), a treatment modality that has been highly debated due to its variable efficacy.
Conclusions:
The results of this study provide genetic support for IDO2 as a contributing factor in PDAC development and argue that IDO2 genotype analysis has the immediate potential to influence the PDAC care decision-making process through stratification of those patients who stand to benefit from adjuvant radiotherapy.
Data from Identification of Therapeutic Vulnerabilities in Small-cell Neuroendocrine Prostate Cancer
Authors: Corella Alexandra N. , Cabiliza Ordonio Ma Victoria Andrea , Coleman Ilsa , Lucas Jared M. , Kaipainen Arja , Nguyen Holly M. , Sondheim Daniel , Brown Lisha G. , True Lawrence D. , Lee John K. , MacPherson David , Nghiem Paul , Gulati Roman , Morrissey Colm , Corey Eva , Nelson Peter S.
Published: April 2023

AbstractPurpose:
Small-cell neuroendocrine prostate cancer (SCNPC) exhibits an aggressive clinical course and incidence rates seem to be increasing following resistance to potent androgen receptor (AR) antagonists. Currently, treatment options are limited and few model systems are available to identify new approaches for treatment. We sought to evaluate commonalities between SCNPC and other aggressive neuroendocrine carcinomas to identify therapeutic targets.
Experimental Design:
We generated whole transcriptome RNA-sequencing data from AR-active prostate cancers (ARPCs) and SCNPCs from tumors collected at rapid autopsy and two other neuroendocrine carcinomas, Merkel cell carcinoma (MCC), and small-cell lung cancer. We performed cross-tumor comparisons to identify conserved patterns of expression of druggable targets. We tested inhibitors to highly upregulated drug targets in a panel of prostate cancer cell lines and in vivo patient-derived xenograft (PDX) models.
Results:
We identified BCL2 as highly upregulated in SCNPC compared with ARPC. Inhibitors targeting BCL2 induced apoptotic cell death in SCNPC cell lines at nanomolar concentrations while ARPC cell lines were resistant. Treatment with the BCL2 inhibitor navitoclax leads to a reduction of growth of SCNPC PDX tumors in vivo, whereas ARPC PDX models were more resistant. We identified Wee1 as a second druggable target upregulated in SCNPC. Treatment with the combination of navitoclax and the Wee1 inhibitor AZD-1775 repressed the growth of SCNPC PDX resistant to single-agent BCL2 inhibitors.
Conclusions:
The combination of BCL2 and Wee1 inhibition presents a novel therapeutic strategy for the treatment of SCNPC.