Tumor-associated Immune Response Research Articles

Prognostic implications of tumor-infiltrating lymphocytes within the tumor microenvironment in gastric cancer

Tumor-infiltrating lymphocytes (TILs) play a regulatory role in the tumor-associated immune response and are important in the prognosis and treatment response of several cancers. However, because of its heterogeneity, the prognostic value of TILs in gastric cancer (GC) is still controversial. Thus, this study aimed to investigate the association between the density of TILs and patients' outcomes in GC. Patients with gastric adenocarcinoma who underwent curative intent gastrectomy were retrospectively investigated. The groups for analysis were determined on the basis of TIL intensity and percentage of CD3+T-cell infiltration by immunohistochemical. Furthermore, Epstein-Barr virus (EBV), microsatellite instability (MSI), T-cell ratio of CD4 to CD8, and programmed death protein ligand 1 (PD-L1) status were evaluated. A total of 345 patients were enrolled: 124 patients with GCs (35.9%) were classified as the low-CD3+TIL group, and 221 patients with GCs (64.1%) were classified as the high-CD3+TIL group. Poorly differentiated histology (P=.014), EBV-positive status (P<.001), PD-L1-positive status (P=.001), and CD4<CD8 (P<.001) were associated with high-CD3+GC. There was no difference regarding MSI status, the degree of tumor invasion (pT), the presence of lymph node metastasis, and pTNM stage between low- and high-CD3+groups. In survival analysis, the high-CD3+group had better disease-free survival and overall survival rates than had the low-CD3+group (P=.055 and P=.041, respectively). In the multivariate analysis, total gastrectomy, lymph node metastasis, advanced pT stage, and low CD3+levels were independent factors related to worse survival. High CD3+TILs levels were significantly associated with improved survival and could serve as prognostic biomarkers in GC. In addition, CD3+T-cell infiltration was related to both EBV-positive and PD-L1-positive GC and may assist in the investigation of targets in immunotherapy.

Abstract PO-089: Opioid-mediated suppression of anti-tumor immunity via peripheral OPRM1 signaling in head and neck squamous cell carcinoma

Abstract Head and Neck squamous cell carcinoma (HNSCC) causes severe pain, beyond what is reported in other cancer types. Opioids are the current backbone of HNSCC pain treatment but may have an immunomodulatory effect in the presence of cancer; T cells express opioid receptors. We recently demonstrated that opioids may affect the efficacy of anti-PD1 monoclonal antibody (mAb) treatment in recurrent/metastastic HNSCC patients; opioid usage was associated with significantly lower progression free survival and overall survival as well as decreased CD8 T cells in the tumor microenvironment. We hypothesized that cancer immunosurveillance is impaired by the immunosuppressive actions of exogenous opioids via peripheral mu-opioid receptor (OPRM1) signaling. A syngeneic mouse oral cancer model was used to determine if analgesic morphine impacted the tumor-associated immune response during tumor progression and in response to anti-PD1 mAb; mouse oral cancer cell line 1 (MOC1) tumor-bearing mice were treated with vehicle or morphine (10mg/kg i.p., 2x daily for 4.5 days) and the tumor-associated immune infiltrate was assessed between groups using flow cytometry. Anti-PD1 mAb (250µg/mouse, 3 × 2 day interval) was initiated directly following morphine treatment. Co-administration of methylnaltrexone (MNTX), a peripheral OPRM1 antagonist used to confirm specificity and site of action of the morphine-induced effects. Finally, any direct effects of morphine on tumor cells were investigated in oral cancer cell lines using quantitative PCR and colorimetric proliferation assays. Morphine induced a 75±5% reduction in CD8+ T cells and a 90±3% reduction in CD19+ B cells in MOC1 compared to sham mice (n=6/group); morphine-induced immunosuppression was completely blocked with co-treatment of MNTX. Studies involving morphine administration prior to anti-PD1 treatment are currently underway but given the substantial suppression in infiltrating lymphocyte populations, efficacy is expected to be lessened. Lastly, Oprm1 expression was not detected at the mRNA level in mouse oral cancer cell lines. In vitro, 10µM morphine did not induce cell proliferation (proliferation relative to vehicle after 48hr; vehicle=100±8.3%, morphine=115.7±9.6%) or improve wound healing (wound closure after 24hr; vehicle=76.2±11.6%, morphine=78.5±11.4%). Taken together, our data suggest that morphine suppresses anti-tumor immunity via peripheral OPRM1 signaling in immune cells but not tumor cells. Further investigation is warranted to determine whether peripheral opioid blockade (i.e. MNTX) can slow tumor progression and improve response to cancer treatments while preserving centrally-mediated analgesia. Citation Format: Lisa A. McIlvried, Mona Yuan, Nicole L. Horan, Megan A. Atherton, Marci L. Nilsen, Dan P. Zandberg, Nicole N. Scheff. Opioid-mediated suppression of anti-tumor immunity via peripheral OPRM1 signaling in head and neck squamous cell carcinoma [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Innovating through Basic, Clinical, and Translational Research; 2023 Jul 7-8; Montreal, QC, Canada. Philadelphia (PA): AACR; Clin Cancer Res 2023;29(18_Suppl):Abstract nr PO-089.

Clinical and Prognostic Biomarker Value of Blood-Circulating Inflammatory Cytokines in Hepatocellular Carcinoma

Introduction: Circulating inflammatory cytokines play critical roles in tumor-associated inflammation and immune responses. Recent data have suggested that several interleukins (ILs) mediate carcinogenesis in hepatocellular carcinoma (HCC). However, the predictive and prognostic value of circulating ILs is yet to be validated. Our study aimed to evaluate the association of the serum ILs with overall survival (OS) and clinicopathologic features in a large cohort of HCC patients. Methods: We prospectively collected data and serum samples from 767 HCC patients treated at the University of Texas MD Anderson Cancer Center between 2001 and 2014, with a median follow-up of 67.4 months (95% confidence interval [CI]: 52.5, 83.3). Biomarker association with OS was evaluated by the log-rank method. Results: The median OS in this cohort was 14.2 months (95% CI: 12, 16.1 months). Clinicopathologic features were more advanced, and OS was significantly inferior in patients with high circulating levels of IL1-R1, IL-6, IL-8, IL-10, IL-15, IL-16, and IL-18. Conclusion: Our study shows that several serum IL levels are valid prognostic biomarker candidates and potential targets for therapy in HCC.

Identification of differentially expressed HERV-K(HML-2) loci in colorectal cancer.

Colorectal cancer is one of the malignant tumors with the highest mortality rate in the world. Survival rates vary significantly among patients at various stages of the disease. A biomarker capable of early diagnosis is required to facilitate the early detection and treatment of colorectal cancer. Human endogenous retroviruses (HERVs) are abnormally expressed in various diseases, including cancer, and have been involved in cancer development. Real-time quantitative PCR was used to detect the transcript levels of HERV-K(HML-2) gag, pol, and env in colorectal cancer to systematically investigate the connection between HERV-K(HML-2) and colorectal cancer. The results showed that HERV-K(HML-2) transcript expression was significantly higher than healthy controls and was consistent at the population and cell levels. We also used next-generation sequencing to identify and characterize HERV-K(HML-2) loci that were differentially expressed between colorectal cancer patients and healthy individuals. The analysis revealed that these loci were concentrated in immune response signaling pathways, implying that HERV-K impacts the tumor-associated immune response. Our results indicated that HERV-K might serve as a screening tumor marker and a target for tumor immunotherapy in colorectal cancer.

Diagnostic and prognostic biomarker value of blood circulating inflammatory cytokines in hepatocellular carcinoma.

e16115 Background: Circulating inflammatory cytokines play critical roles in tumor-associated inflammation and immune responses. Recent data has suggested that several interleukins (ILs) mediate carcinogenesis in hepatocellular carcinoma (HCC). However, the predictive and prognostic value of circulating ILs has yet to be validated. Our study aimed to evaluate the association of the serum ILs with overall survival (OS) and clinicopathologic features in a large cohort of HCC patients. Methods: We prospectively collected data, and serum samples from 767 HCC patients treated at The University of Texas MD Anderson Cancer Center between 2001 and 2014, with a median follow-up of 67.4 months (95% CI: 52.5, 83.3). Biomarker association with overall survival (OS) was evaluated by the Log-rank method. Results: The median OS in this cohort was 14.2 months (95% confidence interval [CI]: 12, 16.1 months). Clinicopathologic features were more advanced, and OS was significantly inferior in patients with high circulating levels of IL1-R1, IL-6, IL-8, IL-10, IL-15, IL-16, and IL-18. Conclusions: In conclusion, our study shows that several serum IL levels are valid prognostic biomarker candidates and potential targets for therapy in HCC.

Catalytically Active Metal-Organic Frameworks Elicit Robust Immune Response to Combination Chemodynamic and Checkpoint Blockade Immunotherapy.

Chemodynamic therapy (CDT) strategies rely on the generation of reactive oxygen species (ROS) to kill tumor cells, with hydroxyl radicals (•OH) serving as the key mediators of cytotoxicity in this setting. However, the efficacy of CDT approaches is often hampered by the properties of the tumor microenvironment (TME) and associated limitations to the Fenton reaction that constrains ROS generation. As such, there is a pressing need for the design of new nanoplatforms capable of improving CDT outcomes. In this study, an Fc-based metal-organic framework (MOF) vitamin k3 (Vk3)-loaded cascade catalytic nanoplatform (Vk3@Co-Fc) was developed. This platform was capable of undergoing TME-responsive degradation without impacting normal cells. After its release, Vk3 was processed by nicotinamide adenine dinucleotide hydrogen phosphate (NAD(P)H) quinone oxidoreductase-1 (NQO1), which is highly expressed in tumor cells, thereby yielding large quantities of H2O2 that in turn interact with Fe ions via the Fenton reaction to facilitate in situ cytotoxic •OH production. This process leads to immunogenic cell death (ICD) of the tumor, which then promotes dendritic cell maturation and ultimately increases T cell infiltration into the tumor site. When this nanoplatform was combined with programmed death 1 (PD-1) checkpoint blockade approaches, it was sufficient to enhance tumor-associated immune responses in breast cancer as evidenced by increases in the frequencies of CD45+ leukocytes and CD8+ cytotoxic T lymphocytes, thereby inhibiting tumor metastasis to the lungs and improving murine survival outcomes. Together, this Vk3@Co-Fc cascading catalytic nanoplatform enables potent cancer immunotherapy for breast cancer regression and metastasis prevention.

De Novo Design and Synthesis of Polypeptide Immunomodulators for Resetting Macrophage Polarization.

Modulating the extracellular matrix microenvironment is critical for achieving the desired macrophage phenotype in immune investigations or tumor therapy. Combining de novo protein design and biosynthesis techniques, herein, we designed a biomimetic polypeptide self-assembled nano-immunomodulator to trigger the activation of a specific macrophage phenotype. It was intended to be made up of (​GGS​GGP​GGG​PAS​AAA​NSA​SRA​TSN​SP)n, the RGD motif from collagen, and the IKVAV motif from laminin. The combination of these domains allows the biomimetic polypeptide to assemble into extracellular matrix-like nanofibrils, creating an extracellular matrix-like milieu for macrophages. Furthermore, changing the concentration further provides a facile route to fine-tune macrophage polarization, which enhances antitumor immune responses by precisely resetting tumor-associated macrophage immune responses into an M1-like phenotype, which is generally considered to be tumor-killing macrophages, primarily antitumor, and immune-promoting. Unlike metal or synthetic polymer-based nanoparticles, this polypeptide-based nanomaterial exhibits excellent biocompatibility, high efficacy, and precise tunability in immunomodulatory effectiveness. These encouraging findings motivate us to continue our research into cancer immunotherapy applications in the future.

The Role of the Microbiome in Pancreatic Cancer.

Simple SummaryPancreatic cancer is deadly cancer characterized by dense stroma creating an immunosuppressive tumor microenvironment. Accumulating evidences indicate that the microbiome plays an important role in pancreatic cancer development and progression via the local and systemic inflammation and immune responses. The alteration of the microbiome modulates the tumor microenvironment and immune system in pancreatic cancer, which affects the efficacy of chemotherapies including immune-targeted therapies. Understanding the role of microbiome and underlying mechanisms may lead to novel biomarkers and therapeutic strategies for pancreatic cancer. This review summarizes the current evidence on the role of the microbiome in pancreatic cancer. Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, with little improvement in outcomes in recent decades, although the molecular and phenotypic characterization of PDAC has contributed to advances in tailored therapies. PDAC is characterized by dense stroma surrounding tumor cells, which limits the efficacy of treatment due to the creation of a physical barrier and immunosuppressive environment. Emerging evidence regarding the microbiome in PDAC implies its potential role in the initiation and progression of PDAC. However, the underlying mechanisms of how the microbiome affects the local tumor microenvironment (TME) as well as the systemic immune system have not been elucidated in PDAC. In addition, therapeutic strategies based on the microbiome have not been established. In this review, we summarize the current evidence regarding the role of the microbiome in the development of PDAC and discuss a possible role for the microbiome in the early detection of PDAC in relation to premalignant pancreatic diseases, such as chronic pancreatitis and intraductal papillary mucinous neoplasm (IPMN). In addition, we discuss the potential role of the microbiome in the treatment of PDAC, especially in immunotherapy, although the biomarkers used to predict the efficacy of immunotherapy in PDAC are still unknown. A comprehensive understanding of tumor-associated immune responses, including those involving the microbiome, holds promise for new treatments in PDAC.

Is the pulmonary microbiome involved in lung cancer pathophysiology?

Abstract Bronchopulmonary cancer represents the neoplasms associated with the highest mortality rate, despite diagnostic and therapeutic advances in recent decades. Early diagnosis is often difficult due to the paucity of symptoms or superinfections. Screening subjects at risk of developing lung cancer include clinical, bacteriological, inflammatory status, and genetic profile assessment. The personal microbiome has an essential role in the physiology of the human body. The gut-lung axis plays an essential role in carcinogenesis, being involved in various pathways. The lung microbiome can contribute to the development of lung cancer either directly by acting on tumor cells or indirectly by modulating the tumor-associated immune response. The gut microbiome can directly affect the response to immunotherapy in patients with non-small cell lung cancer.

Oral Microbiota from Periodontitis Promote Oral Squamous Cell Carcinoma Development via γδ T Cell Activation.

ABSTRACTOral squamous cell carcinoma (OSCC) is a fatal disease, and periodontitis is associated with OSCC development. However, the pathogenesis in the context of OSCC with periodontitis has not been fully understood. Here, we demonstrated that periodontitis promoted OSCC development, accompanied by alterations in the oral bacterial community and the tumor immune microenvironment. The oral microbiota from periodontitis maintained the dominant position throughout the whole process of OSCC with periodontitis, of which Porphyromonas was the most abundant genus. The oral microbiota from periodontitis could activate interleukin-17-positive (IL-17+) γδ T cells directly. The activated γδ T cells were necessary for the IL-17/signal transducer and activator of transcription 3 (STAT3) pathway and promoted M2-tumor-associated macrophage (TAM) infiltration in OSCC proliferation. Our data provide insight into the carcinogenesis of OSCC with periodontitis by outlining the tumor-associated immune response shaped by the oral microbiota from periodontitis. Thus, oral commensal bacteria and IL-17+ γδ T cells might be potential targets for monitoring and treating OSCC.IMPORTANCE The work reveals the role of the oral microbiota from periodontitis in carcinogenesis. Furthermore, our study provides insight into the pathogenesis of OSCC with periodontitis by outlining the tumor-associated immune response shaped by the oral microbiota from periodontitis, which might identify new research and intervention targets for OSCC with periodontitis.

Chemokine CXCL10 Modulates the Tumor Microenvironment of Fibrosis-Associated Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) constitutes a devastating health burden. Recently, tumor microenvironment-directed interventions have profoundly changed the landscape of HCC therapy. In the present study, the function of the chemokine CXCL10 during fibrosis-associated hepatocarcinogenesis was analyzed with specific focus on its impact in shaping the tumor microenvironment. C57BL/6J wild type (WT) and Cxcl10 knockout mice (Cxcl10−/−) were treated with diethylnitrosamine (DEN) and tetrachloromethane (CCl4) to induce fibrosis-associated HCCs. Cxcl10 deficiency attenuated hepatocarcinogenesis by decreasing tumor cell proliferation as well as tumor vascularization and modulated tumor-associated extracellular matrix composition. Furthermore, the genetic inactivation of Cxcl10 mediated an alteration of the tumor-associated immune response and modified chemokine/chemokine receptor networks. The DEN/CCl4-treated Cxcl10−/− mice presented with a pro-inflammatory tumor microenvironment and an accumulation of anti-tumoral immune cells in the tissue. The most striking alteration in the Cxcl10−/− tumor immune microenvironment was a vast accumulation of anti-tumoral T cells in the invasive tumor margin. In summary, our results demonstrate that CXCL10 exerts a non-redundant impact on several hallmarks of the tumor microenvironment and especially modulates the infiltration of anti-tumorigenic immune cells in HCC. In the era of microenvironment-targeted HCC therapies, interfering with CXCL10 defines a novel asset for further improvement of therapeutic strategies.

Abstract CT570: KISIMA-01: A first-in-human trial of the heterologous prime-boost vaccine ATP128/VSV-GP128 with ezabenlimab (BI 754091) in patients with stage IV colorectal cancer

Abstract Background: Most microsatellite stable/mismatch repair proficient (MSS/MMRp) stage IV colorectal cancers (CRC) do not respond to PD-1 inhibition. ATP128, based on the KISIMA platform, is a single chimeric fusion protein, composed of 3 elements essential to generate potent antitumoral cellular immunity: a proprietary cell-penetrating peptide (CPP) for antigen delivery, a proprietary Toll-like receptor (TLR)-peptide agonist with self-adjuvant properties and a modulable multi-antigenic domain (Mad), where the Mad for CRC includes 3 antigens: carcinoembryonic antigen (CEA), Survivin, Achaete-scute complex homolog 2 (ASCL2). VSV-GP128 is a recombinant vesicular stomatitis virus (VSV) carrying the glycoprotein (GP) of a non-neurotropic strain of lymphocytic choriomeningitis virus (LCMV) instead of the native VSV-GP. The GP of the LCMV abrogates neurotoxicity. As viral vector, VSV-GP128 expresses a Mad with identical sequence to ATP128 integrated in a linear, negative-sense, single-stranded RNA genome. Preclinical data have shown that priming with KISIMA vaccine followed by VSV-GP boost induced a large pool of polyfunctional and persistent antigen-specific cytotoxic T cells in the periphery as well as within the tumor in several tumor models. Combining heterologous vaccination with a PD-1 inhibitor further improved its therapeutic efficacy (Das et al., Nature Communication 2021). Methods: KISIMA-01 (NCT04046445) is an open-label, multi-center Phase 1b umbrella trial to investigate the safety, tolerability and immunogenicity of the heterologous prime-boost vaccine AT128/VSV-GP128 in combination with the anti-PD1 ezabenlimab in patients with stage IV MSS CRC. Two different patient cohorts are investigated: 1) maintenance setting (during a chemotherapy free period) after a minimum of 4 months of 1st line standard chemotherapy with clinical benefit (defined as PR or SD) (n=30); 2) resectable liver-limited disease (n=15). ATP128 is given subcutaneously on day 1 (prime); VSV-GP128 is administered intravenously on day 15 as the heterologous boost. ATP128 is again administered on day 29 (injection 3) and then every 4 weeks for the last 3 immunizations. Ezabenlimab is administered every 3 weeks starting with the first ATP128 administration. Blood and tissue samples are collected before, during and after ATP128/VSV-GP128 treatment to monitor the induction of a tumor associated antigen-specific immune response and immune-related changes. Immunogenicity will be analyzed in the peripheral blood using ELISpot, and in the tumor microenvironment by immunohistochemical assessment of tumor-infiltrating lymphocytes (TILs). Clearance of ctDNA is analyzed as an exploratory endpoint. The heterologous prime-boost cohorts (ATP128/VSV-GP128) of the KISIMA-01 trial are recruiting in the US, Switzerland and Belgium. Citation Format: Heinz-Josef Lenz, Thibaud Koessler, Paul Oberstein, Eric Van Cutsem, Sunnie Kim, Ralph Fritsch, Hans Prenen, Michael Morse, Delphine Gani, Madiha Derouazi, Thomas Bogenrieder, Scott Kopetz. KISIMA-01: A first-in-human trial of the heterologous prime-boost vaccine ATP128/VSV-GP128 with ezabenlimab (BI 754091) in patients with stage IV colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT570.

Abstract CT507: ATP128 vaccine with ezabenlimab promotes antigen-specific immune responses in stage IV colorectal cancer in the KISIMA-01 phase 1b trial

Abstract Background: KISIMA࣪ is a vaccine platform based on a single chimeric fusion protein, containing a proprietary cell-penetrating peptide (CPP) for antigen delivery, a proprietary Toll-like receptor (TLR)-peptide agonist with self-adjuvant properties and a modulable multi-antigenic domain (Mad). ATP128 vaccine targets 3 antigens: carcinoembryonic antigen (CEA), Survivin and Achaete-scute complex homolog 2 (ASCL2); it is used in combination with a PD-1 inhibitor in the treatment of MSS/MMR proficient stage IV colorectal cancer (CRC) patients, after first line of standard of care therapy or as perioperative administration in patients with resectable liver metastases. Method: KISIMA-01 (NCT04046445) is an open-label, multi-center Phase 1b trial to investigate the safety, tolerability and immunogenicity of AT128 alone or in combination with the anti-PD-1 antibody ezabenlimab in patients with stage IV CRC. ATP128 is given SC q2w for the first 3 immunizations (prime) and q4w for the last 3 immunizations (boost). Ezabenlimab is administered q3w starting with the first ATP128 administration. Blood and tissue samples are collected before, during and after ATP128 treatment to monitor the induction of a tumor associated antigen-specific immune response (ELISpot) and immune-related changes in the peripheral blood and in the tumor microenvironment by immunohistochemistry (IHC) and flow cytometry. Results: In more than 50% of evaluated patients treated with ATP128 alone or with ezabenlimab, a cellular immune response against at least one out of three antigens was observed as determined by IFN-γ ELISpot analyses of patient PBMCs after the 3rd vaccination. Analysis of liver metastases by IHC indicated that evaluated patients were positive for all 3 antigens in ATP128. Furthermore, for the patients with paired biopsies, a significant increase in CD8 T cells infiltration into the tumor parenchyma was observed after 3 vaccine administrations, along with a significantly higher proportion of CD45RO expressing memory cells within the CD4 population as compared to baseline. Tumor infiltrating lymphocytes (TILs) flow cytometry analysis comparing untreated (historical controls) and ATP128/ezabenlimab-treated patients showed a similar quantity of the different infiltrated subsets but an improved quality of infiltrated T cells, indicated by an increase (more than 2-fold) in proportion of central memory T cells and an impressive decrease of the proportion of cells positive for exhaustion markers expression in KISIMA-01 patients. Conclusions: Analyses indicate induction of ATP128-specific immune response in the peripheral circulation and increased infiltration of TILs into liver metastases with an improved quality of T cells. Citation Format: Heinz-Josef Lenz, Hanz Prenen, Eric Van Cutsem, Thibaud Kössler, Jean-François Mayol, Francesca Trapani, Matthieu Tihy, Laura Rubbia-Brandt, Christian Toso, Thomas Bogenrieder, Elodie Belnoue, Madiha Derouazi, Scott Kopetz. ATP128 vaccine with ezabenlimab promotes antigen-specific immune responses in stage IV colorectal cancer in the KISIMA-01 phase 1b trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT507.

CXCL14 Promotes a Robust Brain Tumor-Associated Immune Response in Glioma.

The immunosuppressive tumor microenvironment present in the majority of diffuse glioma limits therapeutic response to immunotherapy. As the determinants of the glioma-associated immune response are relatively poorly understood, the study of glioma with more robust tumor-associated immune responses may be particularly useful to identify novel immunomodulatory factors that can promote T-cell effector function in glioma. We used multiplex immune-profiling, proteomic profiling, and gene expression analysis to define the tumor-associated immune response in two molecular subtypes of glioma and identify factors that may modulate this response. We then used patient-derived glioma cultures and an immunocompetent murine model for malignant glioma to analyze the ability of tumor-intrinsic factors to promote a CD8+ T-cell response. As compared with isocitrate dehydrogenase (IDH)-mutant astrocytoma, MAPK-activated pleomorphic xanthoastrocytoma (PXA) harbored increased numbers of activated cytotoxic CD8+ T cells and Iba1+ microglia/macrophages, increased MHC class I expression, enrichment of genes associated with antigen presentation and processing, and increased tumor cell secretion of the chemokine CXCL14. CXCL14 promoted activated CD8+ T-cell chemotaxis in vitro, recruited tumor-infiltrating CD8+ T cells in vivo, and prolonged overall survival in a cytotoxic T-cell-dependent manner. The immunomodulatory molecule B7-H3 was also highly expressed in PXA. We identify the MAPK-activated lower grade astrocytoma PXA as having an immune-rich tumor microenvironment and suggest this tumor may be particularly vulnerable to immunotherapeutic modulation. We also identify CXCL14 as an important determinant of the glioma-associated immune microenvironment, sufficient to promote an antitumor CD8+ T-cell response.

Therapeutic effects of ginseng and ginsenosides on colorectal cancer.

Colorectal cancer (CRC) is among the most common malignant diseases with high morbidity and mortality rates. Ginseng and its major extracts, ginsenosides, have been used in medical fields for thousands of years. In particular, their huge anti-cancer potential has drawn a great deal of attention in recent years. There is a large body of evidence that has shown that ginseng and its extracts could significantly inhibit tumor development and progression by suppressing cell proliferation, tumor growth, invasion and metastasis, inducing tumor cell apoptosis, regulating tumor-associated immune responses, and improving the therapeutic effect of chemotherapy. Notably, different subtypes of ginsenosides, even those extracted from the same ginseng, have exhibited distinct anti-cancer functions through different mechanisms. Over the past few years, a large number of studies have focused on how ginseng or various ginsenosides influence CRC development. Therefore, the roles and the potential of ginseng and ginsenosides in the treatment of CRC are summarized in this review. In addition, the biochemical properties of ginseng and ginsenosides are also briefly described.

Survival Advantage Following TAG-72 Antigen-Directed Cancer Surgery in Patients With Colorectal Carcinoma: Proposed Mechanisms of Action.

Patients with colorectal carcinoma (CRC) continue to have variable clinical outcomes despite undergoing the same surgical procedure with curative intent and having the same pathologic and clinical stage. This problem suggests the need for better techniques to assess the extent of disease during surgery. We began to address this problem 35 years ago by injecting patients with either primary or recurrent CRC with 125I-labeled murine monoclonal antibodies against the tumor-associated glycoprotein-72 (TAG-72) and using a handheld gamma-detecting probe (HGDP) for intraoperative detection and removal of radioactive, i.e., TAG-72-positive, tissue. Data from these studies demonstrated a significant difference in overall survival data (p < 0.005 or better) when no TAG-72-positive tissue remained compared to when TAG-72-positive tissue remained at the completion of surgery. Recent publications indicate that aberrant glycosylation of mucins and their critical role in suppressing tumor-associated immune response help to explain the cellular mechanisms underlying our results. We propose that monoclonal antibodies to TAG-72 recognize and bind to antigenic epitopes on mucins that suppress the tumor-associated immune response in both the tumor and tumor-draining lymph nodes. Complete surgical removal of all TAG-72-positive tissue serves to reverse the escape phase of immunoediting, allowing a resetting of this response that leads to improved overall survival of the patients with either primary or recurrent CRC. Thus, the status of TAG-72 positivity after resection has a significant impact on patient survival.

Niraparib exhibits a synergistic anti-tumor effect with PD-L1 blockade by inducing an immune response in ovarian cancer

BackgroundImmune checkpoint blockades (ICBs) therapy showed limited efficacy in ovarian cancer management. Increasing evidence indicated that conventional and targeted therapies could affect tumor-associated immune responses and increase the effectiveness of immunotherapy. However, the effects of Niraparib, one of the poly (ADP) ribose polymerase (PARP) inhibitors, on the immune response remains unclear. Delineating the crosstalk between cytotoxic anticancer agents and cancer-associated immunity may lead to more efficient combinatorial strategies.MethodsProgrammed death ligand 1 (PD-L1) expression in human ovarian cancer cells after PARP inhibitors treatment was examined by western blotting (WB) and flow cytometry. The expression of poly ADP-ribose polymerase (PARP1), PD-L1, and CD8 in human ovarian cancer tissues was detected by immunohistochemistry(IHC). The effect of Niraparib and PD-L1 blockade in ovarian cancer progression was investigated in vivo. The changes of immune cells and cytokines in vitro and in vivo were detected by flow cytometry and enzyme-linked immunosorbent assay (ELISA). Changes of cGAS/STING signal pathway after Niraparib treatment were determined by WB, ELISA.ResultsNiraparib upregulated membrane PD-L1 and total PD-L1 expression in ovarian cancer cells and had a synergistic effect with PD-L1 blockade in vivo. In clinical patient samples, Niraparib augmented cytotoxic CD8+T cell proportion and function. In vivo and vitro, Niraparib can also increase the proportion of T cells and combined with PD-L1 blockade could further enhance the effect. Besides, Niraparib activated the cGAS-STING pathway, increasing the levels of cytokines such as CCL5 and CXCL10, which played a vital role in augmenting the infiltration and activation of cytotoxic T cells.ConclusionsNiraparib could modulate the immune response via the activation of the cGAS/STING pathway, and combination with PD-L1 blockade could further enhance the effect. These results provide a sound theoretical basis for clinical treatment.

TAMI-07. THE IMMUNE MICROENVIRONMENT IN LOWER GRADE GLIOMAS

Abstract The determinants of the tumor-associated immune response in brain tumors are poorly understood. Using tumor samples from two molecularly distinct subtypes of lower grade glioma, MAPK-driven glioma with biallelic inactivation of CDKN2A (n=30) and IDH-mutant, 1p/19q-intact astrocytoma (n=29), we demonstrate qualitative and quantitative differences in the tumor-associated immune response and we investigate the molecular mechanisms involved. Histologically the MAPK-driven gliomas were comprised of pleomorphic xanthoastrocytoma (PXA) (n=11) and anaplastic PXA (n=19). Seven patients had paired samples from two sequential surgeries. Immune cell populations and their activity were determined by quantitative multiplex immunostaining and Digital Spatial Profiling and gene expression was analyzed by Nanostring. Functional studies were performed using established cell lines and two new patient-derived lines from MAPK-driven LGGs. MAPK-driven tumors exhibited an increased number of CD8+ T cells and tumor-associated microglial/macrophage (TAMs), including CD163+ TAMs, as compared to IDH-mutant astrocytoma. In contrast, IDH-mutant tumors had increased FOXP3+ immunosuppressive T regulatory cells. Transcriptional and protein level analyses in MAPK-driven tumors suggested an active cytotoxic T cell response with robust expression of granzyme B, present on 27% of CD8+ T cells, increased MHC class I expression, and altered cytokine profiles. Interestingly, MAPK-driven tumors also had increased expression of immunosuppressive molecules, including CXCR4, PD-L1, and VEGFA. Expression differences for cell surface and secreted proteins were confirmed in patient-derived tumor lines and functional relationships between altered chemokine expression and immune cell infiltration was investigated. Our data provide novel insights into the immune contexture of MAPK driven LGGs and suggest MAPK driven gliomas with biallelic inactivation of CDKN2A may be particularly vulnerable to immunotherapeutic modulation

An Immune Risk Score Predicts Survival of Patients with Myelodysplastic Syndrome

Background: Myelodysplastic syndrome (MDS) was characterized as ineffective hematopoiesis, increased transformation to acute myeloid leukemia (AML), and accompanied by immune system dysfunction. However, the immune signature of MDS remains elusive. Methods: The clinical data (age, sex, international prognostic score system (IPSS), hemoglobin, blast, RBC transfusion dependence, and corresponding subject-level survival) as well as expression profiles of MDS (CD34+ cells) were obtained from Gene Expression Omnibus (GEO: GSE 58831; GSE 114922). A robust prognosis model of immune genes was constructed by the least absolute shrinkage and selection operator (LASSO) regression analysis. Survival analysis for prognostic model was carried out through the Kaplan-Meier curve and Log-rank test. The receiver operating characteristic (ROC) curves and area under the curve (AUC) were used to assess the accuracy of prognostic models. Immune score for different subtype were calculated further by single sample gene set enrichment analysis (ssGSEA). Result: A novel robust immune gene prognostic model indicate that subtype with lower risk score were longer overall survival (OS) than subtype with higher risk score in training cohort (Figure1 A, C). The model was further verified by the validation cohort (Figure1 B, D). The multivariate Cox regression analysis demonstrated the model was an independent prognostic factor for OS prediction with hazard ratios of 56.694 (95% CIs: 9.038−355.648), 3.009 (95% CIs: 1.042−8.692) both in train cohort and external validation cohort respectively (Figure1 G, H). The AUC of 5- year were 0.92 (95% CIs: 0.86 - 0.97) and 0.7 (95% CIs: 0.51 - 0.89) for OS respectively in training cohort and validation cohort (Figure1 E, F). Furthermore, ssGSEA showed higher risk score subtype was significantly associated with higher immune score of check point, human leukocyte antigen (HLA), T cell co-inhibition and type I interferon (IFN) response (Figure1 K-N), which indicating that the poor outcome might be caused by tumor-associated immune response dysfunction partly. Conclusion: We constructed a robust immune gene prognostic model, which have a potential prognostic value for MDS patients and may provide evidence for personalized immunotherapy. Figure Disclosures No relevant conflicts of interest to declare.

Gut Microbiota: Its Potential Roles in Pancreatic Cancer.

Pancreatic cancer is considered a lethal disease with a low survival rate due to its late-stage diagnosis, few opportunities for resection and lack of effective therapeutic strategies. Multiple, highly complex effects of gut microbiota on pancreatic cancer have been recognized as potential strategies for targeting tumorigenesis, development and treatment in recent decades; some of the treatments include antibiotics, probiotics, and fecal microbiota transplantation. Several bacterial species are associated with carcinogenesis of the pancreas, while some bacterial metabolites contribute to tumor-associated low-grade inflammation and immune responses via several proinflammatory factors and signaling pathways. Given the limited evidence on the interplay between gut microbiota and pancreatic cancer, risk factors associated with pancreatic cancer, such as diabetes, chronic pancreatitis and obesity, should also be taken into consideration. In terms of treatment of pancreatic cancer, gut microbiota has exhibited multiple effects on both traditional chemotherapy and the recently successful immunotherapy. Therefore, in this review, we summarize the latest developments and advancements in gut microbiota in relation to pancreatic cancer to elucidate its potential value.