bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunomodulation of pembrolizumab (pembro) treated metastatic melanoma patients (pts) after progression with sequential temozolomide (TMZ): A case series.
Authors: Swami Umang , Monga Varun , Zakharia Yousef , Milhem Mohammed M. 
Published: November 2019

123 Background: Regulatory T cells are increased in melanoma pts and are postulated to impair objective response to immune therapies. Pembro blocks programmed death receptor-1, reverses T-cell suppression and induces antitumor activity. Continuous low dose TMZ has immunomodulatory effects resulting in selective CD4+ lymphopenia of which the T-reg population of CD4+/CD25+ T cells could be decreased significantly. TMZ has demonstrated dramatic responses after IL-2 in metastatic melanoma pts. We evaluated responses with sequential TMZ after progression on pembro in pts with metastatic melanoma. Methods: Medical records of pts with metastatic melanoma treated with pembro and TMZ at Holden Comprehensive Cancer Center between 1/1/2011 and 8/31/2016 were reviewed. Recorded data included BRAF mutation status, treatment doses, serological markers, duration of treatment and treatment related responses (immune RECIST and RECIST 1.1). Results: Overall 10 pts (7 males, 3 females) with metastatic melanoma received sequential pembro followed by TMZ after disease progression or unacceptable toxicity. Eight were BRAF negative and 7 were pretreated with ipilimumab. Median age at time of initiating pembro (2 mg/kg every 3 weeks) was 64 years (range 33-75). Pts received a median of 4 doses (2-19). Median duration of treatment was 88 days (41-464) with stable disease in 3, progressive disease (PD) in 6 and 1 not evaluable for response. All pts thereafter received TMZ (75 mg/m2 daily for 6 weeks on 8 week cycle except 1 who received 200 mg/m2 for 5 days every 4 weeks) after a median of 21.5 days (12-34) from last pembro dose. Median duration on treatment with TMZ was 75 days (20-198) resulting in 1 complete response, 1 partial response, 6 PD and 2 not evaluable for response. Pts with response to TMZ had a higher median baseline lymphocyte count at the time of initiation of pembro (4131 vs. 1715 k/uL, p < 0.05) as well as TMZ (2335 vs. 965 k/uL, p = 0.08) as compared to pts without a response. Conclusions: TMZ is an interesting alternative for metastatic melanoma pts with disease progression on pembro. Our results show a 25% response rate. Further studies in this setting are warranted.
Targeting the glucose metabolism of monocytic myeloid-derived suppressor cells to stimulate cancer immunity.
Authors: Grewal Jaspreet Singh , Al-Rayyan Numan , Ritchie Jamaal , Schowe Paxton , Falkner Cam , Telang Sucheta , Yaddanapudi Kavitha , Chesney Jason Alan ,   University of Louisville
Published: November 2019

126 Background: Myeloid derived suppressor cells (MDSCs) inhibit the expansion of tumor antigen-specific effector CD8+ T cells via different mechanisms including increased expression of arginase, transforming growth factor – β (TGF – β) and indoleamine 2,3-dioxygenase (IDO). Recently, MDSCs were found to over-express hypoxia inducible factor 1 alpha (HIF-1α) which is required for their differentiation. An essential transcriptional target of HIF-1α is 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) which synthesizes fructose 2,6-bisphosphate, an allosteric stimulator of glycolysis and of proliferation via stimulation of cyclin dependent kinase-1 (CDK1). We hypothesized that MDSCs might over-express PFKFB3 which in turn might be required for their function as T cell suppressors. Methods: We used monocytic MDSCs (M-MDSCs) induced by co-culture with A375 melanoma cells, M-MDSCs from metastatic melanoma patients, murine bone marrow MDSCs and splenic M-MDSCs from B16 F10 tumor bearing mice for our studies. T cell suppression assays were performed to analyze M-MDSC suppression and reversal following PFKFB3 blockade. Results: We found that M-MDSCs have increased PFKFB3 expression. We also found that PFK-158 administration in B16 (wild-type) melanoma-bearing mice results in a marked reduction in MDSCs and a simultaneous increase in CD8+ T cell infiltration in the tumors. We analyzed three advanced cancer patients for circulating MDSCs before and after PFK-158 administration as part of a multi-center phase 1 clinical trial. And, we found that the MDSCs were markedly reduced in each patient. In addition, we have generated data for MDSC suppressive activity following in vitro treatment with PFK-158 showing reversal of suppressive activity. Conclusions: Taken together, these data indicate that selective inhibition of PFKFB3 may be a novel approach to target MDSCs and combinations of PFKFB3 inhibitors with immunotherapies may be a rational strategy to promote durable immune-mediated remissions in cancer patients.
Expression of MICA/b, a ligand for natural killer (NK) cell recognition, on human pancreatic adenocarcinoma and potential for NK intervention.
Authors: Djeu Julie , Gilvary Danielle , Trinh Thu Le , Tu Nhan , Coppola Domenico 
Published: November 2019

129 Background: Pancreatic cancer remains a leading cause of cancer-related mortality because of lack of means for early detection and notable refractoriness to standard chemotherapy in advanced stages of disease. Mobilization of the immune system is therefore an important option to explore. Natural Killer (NK) cells are potent effector cells in immune surveillance against cancer and offer a unique advantage because of expression of a C-type, lectin-like, type II transmembrane glycoprotein, NKG2D, on the cell surface. NKG2D is a receptor that specifically recognizes common stress-induced proteins such as MICA/B on tumor cells, targeting them for perforin/granzyme B-mediated destruction. The goal of this study is to examine if MICA/B is expressed on human pancreatic cancer cells, allowing the potential to direct immunotherapy against pancreatic cancer via NK cell therapy. Methods: This study was conducted under an IRB approved protocol. Pancreatic samples were taken from 121 patients with pancreatic ductal adenocarcinoma (PDA) and 103 cases of normal adjacent pancreatic tissues (NP) were included for comparison in a tissue microarray developed in the Tissue Core. All cases were stained for MICA/B AB using the Ventana automated immunostainer Discovery XT (Ventana,Tucson, AZ). Human pancreatic cell lines were also immunostained for MICA/B expression and tested for sensitivity to NK cell lysis in vitro. Results: A significant increase in MICA/B expression was observed during the progression from NP to PDA (p value < 0.0001) in pancreatic tumor tissues. Additionally, all pancreatic cell lines, including MiaPaca, Panc-1, and PCSC, express MICA/B and were readily lysed by NK cells. Conclusions: We report an increase in MICA/B expression during the progression of pancreatic ductal adenocarcinoma and MICA/B may represent a new immunotherapeutic target in pancreatic gastric carcinogenesis.
Gene expression signatures of response to anti-CD19 chimeric antigen receptor (CAR) T-cell therapy in patients with CLL and ALL.
Authors: Orlando Elena , Leary Rebecca , Lacey Simon F. , Fraietta Joseph , Bedoya Felipe , Ambrose David , Wilcox Nicholas , Maude Shannon L. , Frey Noelle V. , Levine Bruce L , Grupp Stephan A. , Porter David L. , Young Regina , Winckler Wendy , Morrissey Michael , June Carl H. , Melenhorst Jan Joseph , Brogdon Jennifer , Bitter Hans 
Published: November 2019

137 Background: The adoptive transfer of autologous T cells genetically modified to express a CD19-specific, 4-1BB/CD3ζ-signaling CAR (CTL019) has shown remarkable activity and induces long-term remissions in a subset of patients with relapsed/refractory chronic lymphocytic leukemia (CLL) and acute lymphoblastic leukemia (ALL). In ALL, CTL019 induces a complete response (CR) in over 90% of patients while in CLL 25% of patients obtain a CR. It is not fully understood why only certain patients respond to therapy. Methods: We employed next generation sequencing of RNA (RNAseq) to identify predictive indicators of response to CTL019. We performed RNAseq on leukapheresis and manufactured product T cells prior to re-infusion from 35 CLL and 7 pediatric ALL patients with heavily pre-treated and high-risk disease. To characterize potency, we performed RNAseq on the infusion product after stimulation with the CAR. Results: We find that durable remission in CLL is associated with gene expression signatures of early memory and T-effector cells, while T cells from non-responding patients are enriched in signatures of T-regulatory cells, terminal differentiation, and exhaustion. In following the results from CLL, we find that pediatric ALL manufactured T cells are significantly enriched for an early memory, naïve T cell state and all achieved a CR. In parallel in vitro experiments, stimulation of the infusion product further demonstrated that CTL019 cells from CRs have an increased capacity for activation upon stimulation. We tested if we could extend these observations to identify a phenotype of T cells that is predictive of response prior to CTL019 manufacturing and find that the signatures predictive of response at the pre-infusion stage are also observed at the earlier leukapheresis time point. Conclusions: These findings suggest that intrinsic T cell fitness dictates response to CAR T cells. These gene expression signatures, along with additional immunological biomarkers, may be used to identify which patients are most likely to respond to adoptive transfer strategies and suggest manufacturing modifications that might potentiate the generation of maximally efficacious infusion products. Clinical trial information: NCT01029366, NCT01747486, NCT01626495.
The impact of checkpoint blockade prior to adoptive cell therapy using tumor-infiltrating lymphocytes for metastatic melanoma: An update from MD Anderson Cancer Center.
Authors: Forget Marie-Andree , Haymaker Cara L. , Hess Kenneth R. , Roszik Jason , Woodman Scott Eric , Fulbright Orenthial J. , Wahl Arely , Flores Esteban , Thorsen Shawne T. , Tavera Rene J. , Ramachandran Renjith , Amaria Rodabe Navroze , Hwu Patrick , Bernatchez Chantale 
Published: November 2019

138 Background: Adoptive cell therapy (ACT) of autologous tumor-infiltrating lymphocytes (TIL) can produce long lasting treatment responses in patients (pts) with metastatic melanoma. In our initial report of 31 treated pts, we demonstrated overall response rate (ORR) of 48%. Due to the evolution of treatment options for metastatic melanoma with heavy reliance on immunomodulatory therapies, we sought to re-evaluate responses in the era of checkpoint blockade. Methods: Pts receive treatment consisting of 7 days of lymphodepleting chemotherapy consisting of cyclophosphamide and fludarabine. High dose interleukin-2 (720,000 IU/kg IV q 8 hrs up to 15 doses) was infused after TIL infusion. Responses were assessed by imaging per irRC. Results: A total of 74 pts have been treated in our initial TIL study with an updated ORR assessment of 43%. Stratification of pts according to their checkpoint blockade immune-modulator therapy prior to TIL ACT, demonstrated that prior Ipilimumab (Ipi) decreased ORR to 33% compared to 51% in checkpoint naïve pts and decreased overall survival (OS) post-TIL therapy (median 7.7 vs 24.6 months respectively). There were too few pts to assess the impact of anti-PD1 as a single agent. A multiparametric analysis revealed that LDH levels at the time of therapy mainly influences OS and ORR to TIL but still could not invalidate the impact of Ipi prior to TIL ACT. The durability of the response was also found to be different between the 2 groups (30% for Ipi prior and 50% No Ipi prior). This new reality also impacted previously reported parameters that correlated with ORR to TIL ACT such as the expression of B-and-T lymphocyte attenuator (BTLA) on CD8+ TIL. Interestingly, assessment of mutation load (ML) of the tumors prior to TIL ACT showed that the check point naïve group display a high ML ( > 100) within their tumor whereas some patients who had Ipi prior to TIL have a low ML ( < 100). Conclusions: Our preliminary analysis shows that pre-treatment with Ipi decreases ORR to TIL ACT. Understanding how prior ipi modifies TIL, the tumor and microenvironment will help to define the full extent of the impact and how to best treat Ipi refractory pts with TIL. Clinical trial information: NCT00338377.
Generation and characterization of antitumor infiltrating lymphocytes from patients with breast cancer for adoptive cell transfer therapy.
Authors: Zhou Juhua , Zhong Yin , Hou Zhongjun , Zhang Jianzhong , Li Yanmin , Yan Senxiang 
Published: November 2019

145 Background: Clinical trials have shown that adoptive cell transfer therapy is a promising method for cancer treatment. In the current study, we aim to generate and characterize anti-tumor tumor-infiltrating lymphocytes from patients with breast cancer for adoptive cell transfer therapy. Methods: In vitro culture method was used to generate anti-tumor, tumor-infiltrating lymphocytes from patients with breast cancer. FACS analysis, ELISA, and Elispot assay were used to characterize tumor-infiltrating lymphocytes. Autologous anti-tumor tumor-infiltrating lymphocytes from patients with breast cancer were used in adoptive cell transfer therapy. Results: FACS analysis indicated that tumor-infiltrating lymphocytes were present in the tumor tissues, but not detectable in the normal breast tissues from patients with breast cancer. Tumor-infiltrating lymphocytes could be generated in vitro from fresh tumor specimens of patients with breast cancer. Both CD4 T cells and CD8 T cells were detected in tumor-infiltrating lymphocytes. Autologous tumor cells could also generate in vitro from fresh tumor tissue samples of patients with breast cancer. Among 22 samples screened, 6 samples (25%) of tumor-infiltrating lymphocytes are tumor-reactive. Anti-tumor, tumor-infiltrating lymphocytes could recognize autologous tumor cells and allogenic tumor cells. After a large scale T cell expansion, anti-tumor reactivity was maintained in tumor-infiltrating lymphocytes. All of tumor-infiltrating lymphocytes were NK cells in some samples from patients with breast cancer, and these NK cells could recognize autologous tumor cells and a panel of allogenic tumor cells. T cell cloning assay demonstrated that some of the tumor-reactive, tumor-infiltrating lymphocytes were CD4 T cells. Conclusions: The results suggest that anti-tumor, tumor-infiltrating lymphocytes may be generated from patients with breast cancer, which may be used in clinical applications of adoptive cell transfer therapy for patients with breast cancer. The clinical trial of adoptive cell transfer therapy using autologous anti-tumor tumor-infiltrating lymphocytes for patients with breast is under way.
Somatic mutation burden in cancer samples determined by targeted next generation sequencing.
Authors: Cyanam Dinesh , Broomer Adam , Mandelman David , Chaudhary Ruchi , Williams Paul D , Nistala Goutam , Gottimukkala Rajesh , Rhodes Kate , Bishop John , Hyland Fiona , Sadis Seth 
Published: November 2019

15 Background: High somatic mutation burden in tumor tissues is associated with the presentation of neoantigens that promote immune responses particularly in the context of immune checkpoint therapies. Herein, we characterize the ability of targeted cancer research panels to generate estimates of somatic mutation burden. Methods: Somatic mutation data from > 8000 cancer samples obtained from The Cancer Genome Atlas (TCGA) was curated and standardized, and the number of single nucleotide variants (SNVs) in exonic regions of each sample determined. Next, the number of SNVs associated with target regions of two Ion AmpliSeq cancer panels (Oncomine Comprehensive Assay [OCA, 146 genes, 0.35 MB]; Comprehensive Cancer Panel [CCP, 409 genes, 1.7 MB]) was likewise determined and the frequency of mutation counts in the exome and the panel target regions was compared. Mutation counts of samples containing truncating mutations in mismatch repair (MMR) and other DNA repair genes were characterized. A facile workflow with less than 60 minutes of hands-on time was developed to estimate mutation counts for a batch of 8 samples using the Ion Chef for automated library preparation and templating followed by sequencing on the Ion S5. Results: The sensitivity of targeted panels in estimating somatic mutation burden was positively correlated with panel size. The area under the Receiver Operating Characteristic (ROC) curve showed that CCP had > 90% sensitivity and > 95% specificity to differentiate high and low mutation burden based on informatics analysis of TCGA data. As expected, truncating mutations in MMR genes were associated with higher somatic mutation counts in colorectal tumor tissue. Using data generated from OCA and CCP, we characterized a set of filters that provided a good estimate of somatic mutation counts when applied to a tumor-only workflow. Conclusions: A simple workflow was developed on the Ion Torrent sequencing platform to estimate somatic mutation burden in cancer samples. The methods described herein will help advance research in immuo-oncology.
DNA vaccine with pembrolizumab to elicit antitumor responses in patients with metastatic, castration-resistant prostate cancer (mCRPC).
Authors: McNeel Douglas G. , Eickhoff Jens C. , Jeraj Robert , Staab Mary Jane , Straus Jane , Rekoske Brian , Liu Glenn 
Published: November 2019

168 Background: We have previously investigated a DNA vaccine encoding prostatic acid phosphatase (PAP, pTVG-HP) in patients with PSA-recurrent prostate cancer, and have demonstrated that this can be safely administered over many months and can elicit PAP-specific T cells. A phase 2 trial is currently underway. In preclinical models, we have found that blockade of regulatory receptors, including PD-1, at the time of T cell activation with vaccination produced anti-tumor responses in vivo. Similarly, we have recently found that patients with prostate cancer previously immunized with a DNA vaccine develop PD-1-regulated T cells. These findings suggested that combined PD-1 blockade with vaccination should elicit superior anti-tumor responses in patients with prostate cancer. Methods: A clinical trial was designed to evaluate the immunological and clinical efficacy of pTVG-HP when delivered in combination or in sequence with pembrolizumab, in patients with mCRPC. Serial biopsies, blood draws, and exploratory FLT PET/CT imaging are being conducted for correlative analyses. Results: While trial accrual continues, 1 of 14 subjects has experienced a grade 3 adverse event. There have been no grade 4 events. Several patients treated with the combination have experienced serum PSA declines, and several have experienced decreases in tumor volume by radiographic imaging at 12 weeks, including one partial response. Expansion of PAP-specific Th1-biased T cells has been detected in peripheral blood samples. Exploratory FLT PET/CT imaging has demonstrated proliferative responses in metastatic lesions and in vaccine-draining lymph nodes. Evaluation of biopsy specimens for recruitment of antigen-specific T cells is currently underway. Conclusions: PD-1 pathway inhibitors have demonstrated little clinical activity to date when used as single agents for treating prostate cancer. Our findings suggest that combining this blockade with tumor-targeted T-cell activation by a DNA vaccine is safe and can augment tumor-specific T cells, detectable within the peripheral blood and by imaging, and result in objective anti-tumor changes. Clinical trial information: NCT02499835.
Effect of imprime PGG on innate immune-activating pharmacodynamic changes in a phase I clinical study in healthy human volunteers.
Authors: Bose Nandita , Ottoson Nadine , Harrison Ben , Lowe Jamie R. , Matson Mark , Qiu Xiaohong , Bykowski Jonas Adria , Rathmann Blaine , Kangas Takashi , Wurst Lindsay R. , Chan Anissa S.H. , Fraser Kathryn , Walsh Richard , Ertelt Katie E. , Leonardo Steven , Fulton Ross , Gorden Keith , Uhlik Mark , Graff Jeremy , Huhn Richard Dale 
Published: November 2019

33 Background: Imprime PGG (Imprime) is currently in clinical development as combination therapy with checkpoint inhibitors. Imprime, a yeast-derived, soluble β-1,3/1,6 glucan is a Pathogen Associated Molecular Pattern (PAMP) that complexes with endogenous anti-beta glucan antibodies (ABA) and activates innate immune effector cells to trigger the anti-cancer immunity cycle. In this study, we sought to investigate the immunopharmacodynamic (IPD) responses of Imprime in healthy human subjects. Methods: Group 1 (n=12) received a single IV infusion of Imprime 4 mg/kg, Group 2 (n=12) received three weekly infusions of 4mg/kg Imprime. Group 3 (n=12) received infusions of 4 mg/kg or 2 mg/kg Imprime on weeks 1, 2 and 5. In groups 1 and 2, six subjects each received premedication with diphenhydramine 50 mg IV and dexamethasone 8 mg IV. IPD changes were measured at various times before, during and after Imprime administration. Results: Peak levels of complement activation products, C5a and SC5b-9 were detected at the end of infusion (EOI). A 2 to 3-fold increase in neutrophil and monocyte numbers were seen 4 hours post-Imprime infusion. Chemokines, especially IL-8 and MCP-1, were consistently detected at EOI. Cellular analyses showed Imprime binding to neutrophils, monocytes, subsets of DC and B cells. 24 hrs after EOI, a population of intermediate monocytes expressing higher levels of the activation markers CD86, PD-L1, and HLA-DR, was observed. Approximately one week post-Imprime, increased switched memory B cells and plasmablasts were detected. Consistent increase in expression of innate immune activation marker genes was evident as well. A substantial drop in free ABA and a concomitant increase in circulating immune complexes were seen at the EOI. Adverse events (AE) were limited to infusion related reactions. Importantly, the IPD changes and the AE were seen in subjects with higher ABA levels. The effect of pre-medications on some of the IPD will also be presented. Conclusions: These human data provide the first evidence linking pre-treatment ABA levels and Imprime IPD, substantiating the use of these pre-treatment ABA levels for patient selection.