bluuebunny/crossref_metadata_2025_split huggingface dataset:
Upregulation of programmed death ligand 1 (PD-L1) on circulating epithelial tumor cells (CETCs) as consequence of adjuvant radiation therapy in primary breast cancer patients.
Authors: Pizon Monika , Schott Dorothea , Pachmann Ulrich A. , Pachmann Katharina , Maeurer Matthias 
Published: July 2019

3 Background: Radiation therapy (RT) is an integral part of the treatment of breast carcinoma but unfortunately many patients experience local recurrence. During the inflammatory response that accompanies radiation tumor cells may develop multiple resistance mechanisms for example the up-regulation of PD-L1 on tumor cells which leads to immune evasion. Since CETCs arise from the tumor it is conceivable that under evolutionary pressure they might share some of the immune escape mechanism inherent to tumor cells. In this study we demonstrate that RT leads to a transitory adaptive up-regulation of PD-L1 expression on CETCs. Methods: CETCs and the expression of PD-L1 and Ki-67 were analyzed from 25 patients with primary non-metastatic breast cancer using the maintrac method. The fraction of PD-L1 and Ki-67 positive CETCs were assessed at baseline, 3 and 6 weeks after start of RT and 6 weeks after end of therapy. Additionally, copy number status of PD-L1 was determined using FISH. Results: Fractionated-dose RT leads to a significant increase in PD-L1 expression on CETCs with the highest expression level midterm of irradiation as compared to baseline (49% vs. 74%, p < 0.01). 6 weeks after end of RT the number of PD-L1 positive CETCs returned to baseline value. The up-regulation of PD-L1 was dose dependent. Patients who received higher total dose had significantly more PD-L1 positive CETCs as compared to patients treated with lower total dose midterm of RT (64% vs. 43, p < 0.05). Before start of therapy there was a correlation between the fraction of PD-L1 and Ki-67 positive CETCs (r = 0.6, p < 0.01). PD-L1 copy number gains were significantly associated with PD-L1 expression (r = 0.6, P < 0.05). Conclusions: RT leads to an up-regulation of PD-L1 expression on CETCs, which could be a possible mechanism of acquired radioresistance. Combining immunomodulatory agents with radiation might have the potential to overcome this resistance and could improve clinical outcome in breast cancer.
Phase I study of cemiplimab, a human monoclonal antibody to programmed death (PD)-1, in Japanese patients (pts) with advanced malignancies: Results from the dose exploration.
Authors: Kitano Shigehisa , Shimizu Toshio , Koyama Takafumi , Ebata Takahiro , Iwasa Satoru , Kondo Shunsuke , Shimomura Akihiko , Fujiwara Yutaka , Yamamoto Noboru , Paccaly Anne Josee , Baum Clifford , Li Siyu , Rietschel Petra , Sims Tasha Nicholle 
Published: July 2019

33 Background: Cemiplimab (REGN2810), a high-affinity, highly potent, human monoclonal antibody to PD-1, has demonstrated a safety profile comparable with that of other anti-PD-1 antibodies and antitumor activity in various solid tumors including cutaneous squamous cell carcinoma and non-small-cell lung cancer (NSCLC) in pts outside of Japan. We present analysis of Part 1 of a two-part, multicenter, open-label, Phase 1 study of cemiplimab in Japanese pts with advanced malignancies. Methods: Part 1 dose exploration pts received either cemiplimab 250 mg (n=6) or 350 mg (n=7) Q3W IV for up to 108 weeks. Tumor measurements were performed every 9 weeks according to RECIST 1.1. Data cut-off date was July 13, 2018. Results: Thirteen pts were enrolled: median age, 62 years (range: 33–75); 8 F. Twelve (92.3%) and 7 (53.8%) pts had received prior cancer-related systemic therapy and radiotherapy, respectively. Median duration of cemiplimab exposure was 13.1 weeks (range: 3.0–54.6). At the data cut-off date Part 1 was fully enrolled and 9 pts (69.2%) had discontinued treatment, primarily due to disease progression (n=7, 53.8%). The most common treatment-emergent adverse events (TEAEs) of any grade were contact dermatitis, rash, and viral upper respiratory tract infection, each occurring in 3 pts (23.1%). The following grade ≥3 TEAEs occurred in 1 pt (7.7%): hypophosphatemia, hyponatremia, autoimmune colitis, and dehydration; the last two events occurred in the same pt. No dose-limiting toxicities were reported. Cemiplimab serum concentrations were as expected from the reported PK characteristics of cemiplimab. Objective response rate (ORR; complete response + partial response [PR]) and disease control rate (ORR + stable disease [SD]) were 23.1% (3 PR) and 53.8% (7/13; 4 SD), respectively. Conclusions: Cemiplimab exhibited substantial antitumor activity in Japanese pts with advanced malignancies. Cemiplimab 350 mg Q3W dosing regimen was selected for the expansion studies. The safety profile was comparable with those previously reported for cemiplimab and other anti-PD-1 agents. Part 2 is open and enrolling pts with NSCLC in Japan. Clinical trial information: NCT02760498.
Localizing radioimmunotherapy via nanochannel device for sustained intratumoral drug delivery for solid tumor treatment.
Authors: Ho Jeremy , Susnjar Antonia , Rhudy Jessica , Sizovs Antons , Lolli Graziano , Pino Ramiro , Chua Corrine Ying Xuan , Butler E. Brian , Demaria Sandra , Grattoni Alessandro 
Published: July 2019

37 Background: Immune related adverse events still occur in up to 91% of patients receiving immunotherapy. Intratumoral administration is a potential solution to limit these events by reducing systemic exposure while increasing local concentration. However, intratumoral injection is hindered by rapid clearance of drug from the tumor. Our group has developed an intratumoral nanochannel implant for sustained delivery of immunotherapy (NDES) as a solution. Recent clinical and preclinical studies have found success in the combination of radiotherapy and immunotherapy in improving both local and distant tumor response. We propose a combination of radiotherapy followed by sustained intratumoral delivery of immunotherapy as a treatment regimen to improve tumor response and reduce side effects. Methods: Mice were implanted with the 4T1 murine mammary carcinoma and separated into treatment and control groups. CD40 agonist antibody was delivered intratumorally via NDES. Radiotherapy was administered at 8 Gy for three consecutive days and implantation of the NDES occurred the day after the final fraction of radiation. The tumor growth curve was plotted and tumor, spleen, lymph nodes, lungs, and blood were collected at the study endpoint for further flow cytometry and histological analysis. Results: The combination of radiotherapy and sustained intratumoral CD40 antibody showed significantly decreased tumor growth rates over radiotherapy or sustained intratumoral immunotherapy alone. Both intratumoral and systemic T-cell activation was observed. Mice treated with sustained intratumoral CD40 antibody showed decreased toxicity when compared to those receiving comparable systemic dosage. Conclusions: Radiotherapy combined with local sustained intratumoral immunotherapy is a potential strategy for improving treatment of solid tumors which currently show suboptimal response to current immunotherapy regimens and for inducing a systemic response to distant metastases while minimizing adverse side effects. The sustained delivery profile of the NDES presents an opportunity for practical intratumoral administration and avoidance of repeated invasive procedures in patients.
Epigenetic biomarkers for noninvasive detection of colorectal cancer.
Authors: Roy Dhruvajyoti , Taggart David , Zheng Lianghong , Liu Dan , Li Gen , Li Mingzhen , Zhang Kang , Van Etten Richard A. 
Published: July 2019

45 Background: Aberrant DNA hypermethylation is known to be a major mechanism for inactivation of cancer-associated genes, including tumor suppressor genes, in colorectal cancer (CRC) and in other human cancers. Cancer-specific DNA methylation patterns of cell-free DNA (cfDNA) isolated from blood samples is a non-invasive method to obtain representative epigenetic information from solid tumors. In the present study, we identified and validated colorectal cancer-specific methylation markers for diagnosis of the disease with high sensitivity and specificity. We also compared the relative amount of DNA methylation at these target sites in relation to colorectal cancer stage. Methods: For marker validation, a total of 154 samples drawn from 68 subjects diagnosed with colorectal cancer (Stage I to IV), 42 healthy donors, 14 subjects with benign colorectal diseases, and 30 subjects diagnosed with other cancer types (breast, liver and lung cancer: 10 cases each) were obtained for a randomized, blinded study. Cell-free DNA was then extracted from the samples, bisulfite converted, and DNA methylation was quantified by using the IvyGene Platform. Results: By quantifying DNA methylation at the target sites, colorectal cancer samples were differentiated from samples drawn from healthy subjects or subjects with benign disease with an overall sensitivity of 93% (95% CI: 86-99) and specificity of 100% (95% CI: 85-100). All stages (I to IV) of colorectal cancer were identified with sensitivities ranging from 67% to 100%. None of the 30 samples drawn from subjects diagnosed with breast, liver or lung cancers were incorrectly identified as a colorectal cancer by the assay, for a calculated analytical specificity of 100%. Conclusions: These results demonstrate the high diagnostic potential of cfDNA methylation markers isolated from blood for the detection of colorectal cancer. Taken together, these findings establish the utility of methylation biomarkers for the detection of colorectal cancers as early as Stage I. In addition, a quantitative analysis of cfDNA provides an opportunity for non-invasive detection and monitoring of disease.
A comparison of microsatellite instability analysis methods in colorectal cancer.
Authors: Lewis Samantha , Peterson Shaun , Oostdik Kathryn , Tomlinson Heather 
Published: July 2019

46 Background: Use of biomarkers for patient treatment stratification is an increasingly important topic with the recent FDA approval of Pembrolizumab and Nivolumab for microsatellite instability (MSI) high/mismatch repair (MMR) deficient cancers. This ground-breaking approval allows physicians to make patient treatment decisions based on molecular biomarker status. Thus, performance of detection methods for these biomarkers is of great importance. The gold standard for MSI analysis in a research setting is PCR followed by fragment analysis to resolve DNA size. Recently, PCR followed by melt curve analysis has been presented as an alternative approach. In this set of experiments these two methods are compared using a subset of human colorectal cancer samples. Methods: A cohort of matched human colorectal cancer and adjacent normal FFPE samples were used for this comparison. Eight pairs were selected that contained subtle shifts, low tumor volume or heterozygosity at microsatellite loci. These samples were then tested for MSI by fragment or melt curve analysis. Samples were then classified as MSI-H, MSI-L or microsatellite stable (MSS) according to manufacturer specifications for melt curve analysis or by an interpretive software for fragment analysis. Results: 40 mononucleotide markers were examined for each method. Melt curve analysis was concordant with fragment analysis in 70% of markers tested (28/40). Of discordant markers, 92% (11/12) were identified as unstable with fragment analysis but were stable by melt curve analysis. Additionally, two of the samples identified as MSI-H by fragment analysis were called MSS or MSI-L using the melt curve analysis method. These preliminary results suggest there may be differences in sensitivity when using challenging samples with melt curve compared to the gold standard method, fragment analysis. Conclusions: The standard method for determining MSI status utilizes PCR and fragment analysis. Recently, melt curve analysis has been proposed as an alternative method. We present preliminary findings of decreased sensitivity with melt curve compared to fragment analysis. Additional studies with a larger, more diverse sample set will be required to define this relationship further.
Investigating the tumor-immune microenvironment in an autochthonous murine model of cholangiocarcinoma.
Authors: Han Booyeon Julia , Ruffolo Luis I. , Jackson Katherine M. , Belt Brian A. , Figueroa Nathania , Murphy Joseph D. , Linehan David , Prieto Peter A. 
Published: July 2019

53 Background: Cholangiocarcinoma (CCA) is the most common liver malignancy within the biliary tree with increasing incidence and poor survival. Although surgical resection can be curative, prognosis remains abysmal with high rates of unresectability and recurrence, and new systemic therapies are needed. CCA tumors are characterized by an abundant inflammatory immune cell infiltrate, yet little is known about the immune dynamics underlying the disease. Here, we present a preclinical murine model of CCA for identifying potential targets susceptible to immune-based therapies. Methods: Mice with targeted activation of KrasG12D and loss of p53 (Kras-p53-/-) in the liver were exposed to 5-Diethoxycarbonyl-1.4-dihydrocollidine for 4 weeks to induce spontaneous CCA tumorigenesis. Immunohistochemistry staining was performed for mouse and human CCA. Immune compartments (bone marrow, spleen, peripheral blood, tumor draining and non-draining lymph nodes, and CCA tumor) of mice were processed for CyTOF analysis. In vitro assays of isolated myeloid leukocytes were performed to demonstrate function. Results: Tumor associated neutrophils (TANs) and tumor associated macrophages (TAMs) were present in high levels in human CCA tumors and the murine model. CyTOF analysis demonstrated mobilization of TANs, TAMs, and CCR2+ inflammatory monocytes into the tumor. The checkpoint marker PD-1 was upregulated on CD8+ and CD4+ T cells and associated with PD-L1+ TANs, TAMs, monocytes, and dendritic cells. The immunosuppressive tumor microenvironment was also characterized by TAMs expressing IL-10, TGFβ, and arginase 1; regulatory B cells expressing IL-10 and TGFβ; and Gata3+ TH2 cells. Isolated myeloid leukocytes suppressed T cell proliferation and induced invasive migration. Conclusions: Kras-p53-/- mice developed CCA tumors histologically similar to human disease: the data portray immunosuppressive cells in the tumor microenvironment, a possible obstacle for an effective anti-tumor response. Understanding the immune dynamics of immunosuppressive populations within the tumor microenvironment will be key to mount a potent therapeutic response for durable remission and improved survival.
Breaking immune tolerance for the treatment of pancreatic cancer: Phase I/II clinical experience.
Authors: Nam David , Hwang Larn , Trieu Vuong N. 
Published: July 2019

54 Background: Escalating Intratumoral heterogeneity resulting in xenogenization which is countered by overexpression of TGF-β. Here we report on the use of OT-101/Chemo to break immune tolerance to cure pancreatic cancer (PC). OT-101 is an antisense against TGF-β2. Methods: Total of 37 pts 2nd line and beyond received OT-101 with option to go on subsequent Chemo (OT-101/Chemo) or Best Supportive Care (BSC) (OT-101/BSC). Stratification by treatment line, schedule, metastasis location, disease control (DC), and baseline CA19-9, was performed. Plasma levels of 31 cyto-/chemokine were measured in a subset of 12 pts. Results: mOS of the 18 pts receiving OT-101/Chemo was 9.4 mos vs. OT-101/BSC (2.8 mos, p=0.0004). No significance was observed on stratification. However, pts with only liver metastasis had a mOS of 9.5 mos while those with liver metastasis and others only had a mOS of 4.7 mos (p=0.0077). Among the former, 1006 has Complete Response beyond 77.3 mos and 1022 had Stable Disease with OS of 40.3 mos; and OS was higher with OT-101/Chemo – 12.4 mos versus 1.9 mos, p=0.0006. There were 16 of 37 pts with DC, with mOS of 9.7 mos vs. 3.0 mos (p<0.0001); and OS was higher with OT-101/Chemo – 11.8 mos vs. 5.0 mos, p=0.0021. Pts exhibited spike in IL-8 level which returned to basal level at treatment stop. R squares relating the IL-8 spike and OS were 0.8522 and 0.9895 and p values were 0.0011 and 0.0053 for OT-101/Chemo and OT-101/BSC, respectively. Preclinically, OT-101 enhanced PBMC activity in cell kill assay and in vivo xenograft. Conclusions: The MOA for OT-101/Chemotherapy is consistent with the reactivation of immunity during TGF-β suppression and subsequent boosting/expansion of immunity during Chemo. Contrary to traditional tumor vaccine- this is universally applicable to all patients.
Developing a new urine cell flow cytometry analysis of PD-L1 expression and DNA content for diagnosis of bladder cancer.
Authors: Alanee Shaheen Riadh , Deebajah Mustafa , Chen Pin-I , Wang Alice (Xiaoyang) , Patterson Bruce Kendrick 
Published: July 2019

60 Background: Bladder cancer is the fifth most common cancer in the United States. PD-1/PD-L1, a pathway used by cancer cells to evade immune response, correlates with bladder cancer severity and has emerged as a target in bladder cancer treatment. Chromosomal instability is also a prominent feature associated with the development of bladder cancer. A method for unbiased analysis of PD-L1 expression and DNA content in cells from urine samples promises to be a new test for diagnosis of bladder cancer. Methods: To evaluate the PD-L1 expression and DNA content, we developed a 4-color flow assay. Cells in voided urine samples were pelleted, fixed in incellMAX (IncellDx Inc.) and stained with antibodies against pan-cytokeratin (CK), CD45, PD-L1 and a cell cycle dye. The stained samples were analyzed by a flow cytometer alongside stained control cells. Results: Fifty bladder cancer patient and 15 normal donor urine samples were collected and tested with this assay. We could distinguish epithelial cells (pan-CK+) and white blood cells (WBCs, CD45+) in urine samples and obtain PD-L1 expression and DNA content information simultaneously from these cell populations. The patient samples showed a significantly higher percentage of WBCs with substantial PD-L1 expression (P < 0.001). The percentage of PD-L1 positive epithelial cells was not distinguishable between normal donor and patient samples. However increased post G1 epithelial cells ( > 5%) were observed in a majority of bladder cancer patients, with around 25% of samples showing a DNA index above 1.05. Conclusions: We developed a flow cytometry-based method to investigate PD-L1 and DNA content simultaneously in cells from urine samples that could provide us with a new method to accurately identify bladder cancer patients through urine testing.
Breaking immune tolerance for the treatment of glioblastoma: Phase IIb clinical trial experience.
Authors: Hwang Larn , Nam David , Trieu Vuong N. 
Published: July 2019

71 Background: Intratumoral heterogeneity (IH) resulting in the temporal and spatial diversification of tumor subclones. IH occurs progressively during tumor development inherent to the individual predilection to mutation and in the face of counterselections by exogenous therapies and/or endogenous immune surveillance. The xenogenization is countered by immunosuppression via overexpression of TGF-β. Here we compare the use of temozolomide (TMZ) and OT-101/TMZ to break immune tolerance to glioblastoma (GBM) for the cure. OT-101 is an antisense against TGF-β2. Methods: This is a phase IIb, multi-national, multi-center, open-label, active-controlled, randomized parallel group dose-finding study to evaluate the efficacy and safety of OT-101 in adult patients with recurrent high-grade glioma, administered intratumorally as continuous high-flow microperfusion over a 7-day period every other week. A total of 134 patients, 89 patients in the OT-101 test group and 45 patients in the standard chemotherapy (TMZ) control group were assessed. Results: Multiple rounds of TMZ broke the immune tolerance as shown by increase in overall survival (OS). mOS increased from 5.6 mos, 7.9 mos, to 36.6 mos with 1 round, 2 rounds, and 3 rounds of TMZ, respectively (p<0.0001). For OT-101, mOS increased from 4.6 mos to 21.6 mos with just one round of TMZ (p<0.0001) reducing the negative side effects of TMZ. Treatment sequencing was important as lead-in OT101 followed with subsequent TMZ was more effective than TMZ prior to OT-101 (26.2 mos vs. 4.8 mos, p<0.0001). Conclusions: The MOA for OT-101/TMZ is consistent with the reactivation of immunity during TGF-β suppression and subsequent boosting/expansion of immunity during TMZ. Contrary to traditional tumor vaccine- this is universally applicable to all patients.
The anti-tumor effect of oral cancer vaccine using Bifidobacterium as a platform for displaying Wilms’ tumor 1 protein.
Authors: Minagawa Hikaru , Hashii Yoshiko , Nakagawa Natsuki , Nakajima Hiroko , Oka Yoshihiro , Katayama Takane , Shirakawa Toshiro , Ozono Keiichi 
Published: July 2019

72 Background: The gut microbiota plays an important role in shaping systemic immune responses. We have developed a WT1 oral cancer vaccine using a recombinant Bifidobacterium Longum ( B. Longum) as a platform for displaying murine WT1 protein ( B. Longum-mWT1). The Wilms’ tumor 1 (WT1) gene, which encodes a zinc finger transcription factor, is reportedly overexpressing in various tumors and one of the most promising tumor-associated antigens for cancer immunotherapy. In order to examine anti-tumor effects of this oral vaccine, we administered it orally into mice inoculated with WT1+-expressing brain tumor which doesn’t respond to existing treatment. Methods: The synthesized murine-WT1 gene (117-439 amino acid residues) was fused to galacto-N-biose/lacto-N-biose I binding protein (GLBP) coding gene. GLBP is a membrane protein on the wild-type B. Longum cell wall, which is used as an anchor to display antigen. The resulting plasmid carrying GLBP-WT1 was introduced into B. Longum by electroporation. We inoculated mouse glioma cell lines (Gl261) subcutaneously into the C57BL/6J. C57BL/6J mice received oral administration of B. Longum-mWT1 every day or subcutaneous administration of WT1126 peptide with montanide adjuvant on days 1, 8, 15, 22, 29, and 36. Results: The tumor volume of the mice treated with B. Longum-mWT1 (n = 5) was significantly smaller than that of the mice given WT1 peptide vaccine (n = 5) ( P < 0.05). The frequency of CD8+/WT1-tetramer+ CTLs was higher in B. Longum-mWT1 and WT1 peptide vaccine groups than in PBS group, and the high frequency was maintained in B. Longum-mWT1 group. In the mouse with B. Longum-mWT1, the frequency CD8+/WT1-tetramer+ CTLs in mesenteric lymph node and spleen was higher than that in Peyer’s patch. The number of invasive CD8+ T cells in brain tumor was higher in the B. Longum-mWT1 group than in the PBS group. B. Longum-mWT1 induced significantly higher in vitro cytotoxicity against Gl261 cells than WT1 peptide. Conclusions: We confirmed that B. Longum-mWT1 can induce strong cellular immunity and the maintenance of this effect. These results suggest that it is a novel oral anti-cancer agent for treating glioblastoma, for which no effective treatment has been developed.