Immune Checkpoint Inhibitors Research Articles

Abstract B014: NRF2 regulation of the immune microenvironment in breast cancer

Abstract Immune checkpoint inhibitors (ICIs) have emerged as a significant advance in the treatment of various cancer types, including breast cancer, though their efficacy varies widely depending on the cancer subtype and the stage of the disease. Following their initial approval in metastatic triple-negative breast cancer (TNBC), ICIs have shown promising results in other contexts, including early-stage cancers and ER+ and HER2+ subtypes. However, even in advanced TNBC the objective response rate to monotherapy ICI is only ∼20%. These results highlight the need to better understand determinants of ICI response in breast cancer. A detailed, high-resolution definition of the tumor immune microenvironment (TIME) will be critical for predicting and engineering effective responses to ICIs. In previously published work, we and others found that the antioxidant transcription factor NRF2 is constitutively active in breast cancer and is associated with tumor recurrence, metastasis, and poor prognosis. However, the mechanisms through which NRF2 promotes breast cancer progression remain unclear. In the current study, we explore the role of NRF2 in reshaping the TIME and its impact on breast cancer progression using preclinical models, flow cytometry, and transcriptomic analyses. We find that NRF2 is constitutively activated in a subset of human and mouse breast cancers where it functions to suppress inflammatory gene expression. In models of recurrent and metastatic mammary tumors, NRF2 knockdown results in a marked reduction in tumor growth rates. Furthermore, the NRF2 inhibition significantly alters the composition of innate and adaptive immune cell populations within the tumor microenvironment. Cytokine profiling revealed that these immune alterations are associated with increased levels of inflammatory cytokines in NRF2-deficient tumor cells compared to controls. RNA sequencing of tumor cells further supports the observed shifts in the immune landscape associated with NRF2 deficiency. Collectively, our findings demonstrate that the loss of NRF2 impairs tumor growth in part through remodeling the TIME and suggest that NRF2 may be a promising therapeutic target for sensitizing breast cancers to ICIs. Citation Format: Yasemin Ceyhan Ozdemir, James V. Alvarez. NRF2 regulation of the immune microenvironment in breast cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr B014.

Abstract C044: Single cell RNA-sequencing coupled with lineage tracing identifies novel clonal populations associated with immunotherapy resistance

Abstract Although immune checkpoint inhibitors (ICIs) have revolutionized melanoma treatment, many individuals either show no response or eventually develop acquired resistance. This variability could be linked to differences in the tumor immune microenvironment, pre-existing drug-resistant cells or treatment induced changes in melanoma cell states. Using single cell RNA sequencing (scRNA-seq) coupled with heritable barcodes, this study aims to lineage trace changes in melanoma transcriptional cell states and map changes in the tumor immune microenvironment to uncover if preexisting and/or therapy-induced melanoma transcriptional cell states lead to resistance to ICIs. In this study, we used YUMMER1.7 mouse melanoma cells which were transduced with barcodes under conditions that allow delivery of a single unique barcode to each cell, this served as a cell lineage tag. Each barcode is heritable and stably transcribed into RNA molecules so that individual barcoded cells can be matched with a gene expression profile from scRNA-seq outputs. The barcoded cells were subcutaneously injected into C57BL/6 mice, and once tumors were established, mice were treated with 3 cycles of anti-PD-1 and anti-CTLA-4 therapy. Lineage tracing and scRNA-seq analyses were performed on tumors harvested prior to treatment, early on treatment (Day 6), during minimal residual disease (Day 13) and upon relapse. Early on treatment (Day 6)- two tumour groups were harvested, those that responded well and others that only partially responded. Our results showed that during the early on treatment phase (Day 6) tumors that responded well and those that only partially responded displayed distinct barcodes. Additionally, prevalent barcoded cells identified at the minimal residual disease phase were also dominant upon relapse. Analysis of the transcriptional states is underway to determine if ICI therapy induces transcriptional heterogeneity in sensitive and tolerant cells and if a particular or several transcriptional states lead to relapse. This study will potentially identify predictive response biomarkers and vulnerabilities of ICI naïve and resistant cells that could be targeted to improve outcomes for melanoma patients. We will also identify neoadjuvant approaches, to remove the inherent heterogeneity within the tumor cell population, facilitating a more uniform sensitivity to ICIs. Citation Format: Reem Saleh, Riyaben Patel, Dane Vassiliadis, Fayrouz Hammal, Benjamin Blyth, Xin Du, Katie Fennell, Mark A. Dawson, Grant A. McArthur, Karen Sheppard. Single cell RNA-sequencing coupled with lineage tracing identifies novel clonal populations associated with immunotherapy resistance [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C044.

Abstract C046: PARP inhibitors as immune modulators in metastatic ovarian cancer treatment

Abstract Epithelial ovarian carcinoma (EOC) is one of the top five causes of cancer-related death in women. Most patients with EOC achieve initial remission after primary or interval cytoreductive surgery combined with platinum-taxane chemotherapy. However, mutations in BRCA1 or BRCA2 genes, which lead to homologous recombination (HR) defects, play a crucial role in platinum sensitivity and justify the use of poly (ADP-ribose) polymerase (PARP) inhibitors as maintenance therapy, commonly linked to extended progression-free survival (PFS). Besides their direct cytotoxic and cytostatic effects, PARP inhibitors (PARPi) have shown significant immunostimulatory properties by disrupting DNA repair in cancer cells, and opening possibilities for synergy with immune checkpoint inhibitors (ICIs). In this study, we investigate the immunomodulatory effects of PARPi using multiparametric flow cytometry, multiplexed immunolabeling, single-cell transcriptomics, and functional assays in an experimental BR5Brca1-/- syngeneic mouse model and human EOC tumor samples. We examine the molecular and cellular mechanisms that can be exploited to develop more effective combination therapies. PARPi may increase the mutational burden in EOCs due to unresolved DNA damage and the release of damage-associated molecular patterns (DAMPs), thereby increasing T-cell infiltration. In addition, PARPi appear to promote potent type I interferon (IFN) secretion through the activation of cGAMP synthase and the stimulator of the interferon genes (STING) pathway. In combination with ICIs, PARPi showed a beneficial effect on the balance between adaptive anti-tumor immunity and innate myeloid components, leading to an improved cytotoxic T-cell response, as observed in mouse models and HGSOC tumor samples. These observations emphasize the role of strategically designed combinations of PARPi and immunotherapeutic agents, which could be the key to overcoming immunosuppression in the EOC microenvironment, thereby improving clinical outcomes. Citation Format: Sarka Vosahlikova, Peter Holicek, Irena Moserova, Michal Hensler, Romana Mikyskova, Lenka Kasikova, Josef Pasuvka, Jana Drozenova, Katerina Mojzisova, Marek Kovar, Iain McNiesh, Michael Halaska, Lukas Rob, Sandra Orsulic, Milan Reinis, Lorenzo Galluzzi, Radek Spisek, Jitka Palich Fucikova. PARP inhibitors as immune modulators in metastatic ovarian cancer treatment [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C046.

Abstract B012: Understanding the role of VISTA in regulating T cell function and the therapeutic potential of blocking VISTA in triple negative breast cancer

Abstract Triple-negative breast cancer (TNBC) is the most aggressive and highly metastatic breast cancer subtype with limited effective treatment options. Immunotherapy with immune checkpoint inhibitors (ICIs) targeting checkpoint molecules have been widely used and have shown therapeutic efficacy in treating multiple malignancies in the last decade. In TNBC, ICI targeting PD-1, alone or in combination with chemotherapy has been approved for the treatment of patients with both early and advanced stage of the disease. Although, there has been significant clinical benefit achieved from anti-PD-1 and chemotherapy, treatment efficacy is often limited to a subgroup of patients. The limited response to ICIs has been attributed to the increased infiltration of immunosuppressive cells (including MDSCs, neutrophils and tumor-associated macrophages), more importantly, the upregulation of alternative immune checkpoint receptors/ligands that may further suppress cytotoxic T cells (CD8+ T cells) in the tumor microenvironment (TME). Therefore, it has been suggested that targeting other immune checkpoint molecules may be more effective in bolstering anti-tumor immune response. V- domain Ig suppressor of T-cell activation (VISTA) is one of the immune checkpoint molecules attracting increasing attention in the context of anti-tumor immunity due to its broad expression across various cancer types and increased expression upon development of immune checkpoint resistance. However, the role of VISTA in regulating the anti-tumor immune response and its therapeutic potential in TNBC remains unclear. In our study, we observed that VISTA is expressed in TNBC patients, predominantly in neutrophils and macrophages. In the Py230 murine breast cancer model, VISTA expression increased upon paclitaxel (PTX), anti-PD-L1 and paclitaxel combined with anti-PD-L1 treatment compared to the control group, suggesting its potential role as a resistance mechanism in sustaining or further inhibiting T cells. In the Py230 model, VISTA blockade increased the infiltration and activation of CD8+ T cells, as evidenced by the higher number of CD8+ T cells, increased CD69+CD8+ T cells, and Granzyme B production, indicating that VISTA blockade improved CD8+ T cells mediated anti-tumor immunity. To functionally test the role of VISTA, we stimulated CD8+ T cells and co-cultured them with naïve macrophages or tumor educated macrophages in the presence or absence of VISTA blocking antibody. Tumor educated macrophages showed increased immunosuppressive activity which was abrogated with VISTA blockade. Moreover, we found that the immunosuppressive effect of macrophages on T cell activation needs direct cell-cell interaction between VISTA on macrophages and T cells. In conclusion, this study shows the mechanism of action of VISTA in the regulation of T cells mediated anti-tumor immune response and provides the rationale for targeting VISTA in TNBC. Citation Format: Maidinaimu Abudula, Yuliana Astuti, Meirion Raymant Raymant, Vijay Sharma, Michael Schmid, Ainhoa Mielgo. Understanding the role of VISTA in regulating T cell function and the therapeutic potential of blocking VISTA in triple negative breast cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr B012.

Abstract C047: AGX101: Preclinical evaluation of a TM4SF1-directed tubulin inhibitor conjugate with ongoing first-in-human trial

Abstract Introduction: TM4SF1 (Transmembrane-4 L-Six-Family-Member-1) is an endothelial marker with critical roles in angiogenesis, as well as a tumor cell antigen that contributes significantly to invasion and metastasis. TM4SF1 is upregulated 20-fold in angiogenic tumor vascular endothelium compared to normal vasculature endothelium and exhibits a unique nuclear internalization pathway. AGX101 is a novel tubulin inhibitor conjugate specifically directed against TM4SF1, delivering a potent maytansinoid payload directly to the nucleus of cells within the tumor microenvironment. Delivery to both the vascular and tumor cell compartments of the tumor results in three mechanisms of action (MoAs): (1) activation of tumor immune surveillance, (2) tumor blood supply deprivation, and (3) direct tumor cell killing. Methods: TM4SF1 expression was assessed across solid tumor samples using immunohistochemistry. Safety and pharmacokinetics of AGX101 were evaluated in non-human primates, with escalating doses to determine the highest non-severely toxic dose (HNSTD). Efficacy studies were also conducted in mouse models, enabling assessment of the minimum effective dose (MED) needed to engage each of the three MoAs. The combination of HNSTD and MED enables calculation of a therapeutic index (TI). Preclinical efficacy studies used either AGX101 (in human tumor xenograft models, to study the tumor cell killing MoA) or AGXB01, a rodent surrogate of AGX101, to study vascular and immune MoAs and all three MoAs in syngeneic mouse cancer models. The potential for synergy with immune checkpoint inhibitors (ICIs) was also investigated. A first-in-human study of AGX101 in patients with advanced solid tumors with the primary objective of safety and dose-limiting toxicities (DLTs) has initiated. Results: TMFS41 is broadly expressed across solid tumors with increasing scoring intensity in higher grade tumors. In non-human primates, AGX101 exhibited a favorable safety profile, being tolerated at relatively high doses and with dose dependent, monitorable, and reversible effects. In preclinical efficacy studies, AGXB01 and AGX101 as monotherapies demonstrated robust efficacy through each of the three MoAs in multiple syngeneic, xenograft, and orthotopic tumor models in mice and rats as well as non-tumor models of angiogenesis. Measured by exposure, TI was large. Additionally, AGXB01 was shown to potentiate the effects of ICIs in syngeneic mouse models (CT26, Renca, and B16-F10), suggesting a potential synergistic approach in cancer therapy. The first dose level of AGX101 monotherapy in humans has cleared without DLTs. Conclusion: AGX101, targeting the TM4SF1 antigen, represents a promising new approach in cancer therapy. The preclinical data suggest that AGX101 could provide a significant therapeutic benefit by novel and differentiated mechanisms of action, namely selectively targeting the tumor vasculature and potentiating immune-based therapies. Further clinical development of AGX101 is ongoing. Citation Format: Ildefonso Ismael Rodriguez Rivera, Meredith S. Pelster, Shou-Ching Jaminet, Paul Jaminet, Glen J. Weiss. AGX101: Preclinical evaluation of a TM4SF1-directed tubulin inhibitor conjugate with ongoing first-in-human trial [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C047.

Abstract PR010: TRPV1+ sensory innervation as a novel driver of ovarian cancer progression

Abstract Introduction: A primary challenge currently faced in ovarian cancer (OVCA) treatment is that patient prognoses remain poor despite current therapeutic interventions. Overall survival for OVCA patients with advanced disease is <30%, and most patients recur within 5 years. As such, there is a critical need for new therapies that can overcome OVCA chemoresistance and produce meaningful increases in patient survival. Recent efforts that have targeted the tumor microenvironment (TME), such as immune checkpoint inhibitors, have been successful in some cancers but have limited therapeutic benefit when used to treat OVCA. Thus, new TME targeting therapies must be developed to effectively treat OVCA patients. A novel TME component ripe for therapeutic targeting are the nerve fibers that infiltrate tumors. Recent studies in several cancers have shown that tumor innervation can promote tumor growth/metastasis. However, in ovarian cancer the role of innervation in promoting cancer progression remains a gap in knowledge. Here we show that Transient Receptor Potential Cation Channel Subfamily V Member 1 (TRPV1)+ sensory innervation plays a significant role in driving ovarian cancer progression. Methods: We performed IHC staining to determine the extent of TRPV1+ nerve infiltration in OVCA vs normal reproductive tissue in patients. We examined the ability of OVCA cells to promote tumor innervation using a neurite outgrowth assay. We utilized both syngeneic and patient derived xenograft (PDX) mouse models of ovarian cancer metastasis, where mouse or human OVCA cells were injected intraperitoneally, to explore the functional role of TRPV1+ sensory nerves in OVCA. TRPV1+ sensory nerves were ablated genetically using TRPV1 driven expression of diphtheria toxin alpha (DTA) or chemically using resiniferatoxin. TRPV1+ sensory nerves were activated pharmacologically using capsaicin. Results: Analysis of patient samples showed that TRPV1+ sensory innervation is much higher in ovarian tumors vs benign reproductive tissue. We found that conditioned media from OVCA cells was able to promote neurite outgrowth of dissociated mouse sensory neurons. Ablation of TRPV1+ sensory nerve fibers in vivo caused reduced tumor burden and prolonged survival in our syngeneic and PDX OVCA mouse models. Stimulation of TRPV1+ sensory nerves with capsaicin accelerated OVCA growth and decreased survival in tumor bearing mice. Conclusions: Our results establish TRPV1+ sensory innervation as a novel driver of OVCA growth/metastasis and a potential therapeutic target for OVCA treatment. Significance to tumor microenvironment field: Our data add to a growing body of evidence that sensory nerves are pro-tumorigenic in multiple cancer types and could be therapeutically targeted for cancer treatment. Citation Format: Matthew Knarr, Katherine Cummins, Dusan Racordon, Hunter Reavis, Timothy Lippert, Ryan Hausler, Priyanka Rawat, Jamie Moon, Dave S.B. Hoon, Roger Greenberg, Paola Vermeer, Ronny Drapkin. TRPV1+ sensory innervation as a novel driver of ovarian cancer progression [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr PR010.

Abstract C030: Timing of melanoma brain metastasis seeding dictates the immunomodulatory effect and efficacy of systemic anti-CD40 agonist therapy

Abstract Introduction: Melanoma brain metastasis (MBM) affects nearly 50% of patients with advanced melanoma. Despite progress in systemic therapies, particularly immune checkpoint inhibitors, intracranial responses remain highly variable. The CD40/CD40L axis and its pleiotropic effects on the anti-tumoral immune response has the potential to improve MBM treatment. Our aim was to investigate whether the timing of MBM seeding, in a two-site mouse model of MBM, impacts the intracranial efficacy of anti-CD40 agonism (aCD40). Methods: 2 x 105 B16F1-cOVA murine melanoma cells were subcutaneously (s.c.) injected in the right flank in C57BL/6 mice (5F, 5M). After 3 days, 1 x 105 B16F1-cOVA cells were intracerebrally (i.c.) injected into the right striatum under stereotaxic guidance (early MBM’ cohort). A separate cohort of C57BL/6 mice (5F, 5M) had s.c. injection of B16F1-cOVA cells, followed by an i.c. injection of B16F1-cOVA cells after 5 days (‘late MBM’ cohort). In both experimental cohorts, the mice were randomly allocated to receive either an aCD40 antibody or an isotype IgG antibody (control) intraperitoneally on days 4 (D4) and 7 (D7) post-i.c. injection (D0). S.c. tumor volume and survival data were serially collected. Separately, tumor-bearing mice treated with either aCD40 or IgG (n = 4 per early/late MBM groups) were euthanized day 9 (D9) post-i.c. injection and tissues (blood, brain tumor [BT], and flank tumor [FT]) were collected for immune profiling by spectral flow cytometry. Results: The early MBM cohort showed a significant s.c. tumor response to aCD40 therapy with a mean D9:D4 s.c. tumor volume ratio of 2.81 (SD±2.05) vs 16.51 (±13.10) in the IgG group (unpaired t-test; p=0.0497). The late MBM cohort showed no significant difference in s.c. tumor response between aCD40 or IgG (D9:D4 ratio 1.52±1.00 vs 1.20±0.83; p=0.5999). Survival increased in early MBM following aCD40 vs IgG (median 20 days vs 13 days; logrank test, p=0.0078), which was not replicated in late MBM (median 21 days vs 19 days; p=0.7717). Systemic aCD40 led to reduced circulating B cells, most expressing CD11b, and increased monocytes, compared to IgG treatment. In the BT, there were higher infiltration of CD8 T cells (normalized to microglia), including OVA+ CD8 T cells, and CD4 T cells in early MBM treated with aCD40 vs IgG. Systemic aCD40 induced more infiltrating SIRP1a+ cDC2 cells than XCR1+ cDC1 cells and vice versa in the IgG group, in both the BT and FLT. Meanwhile, infiltrating B cells were predominantly CD11b+ in aCD40 groups in the BT, regardless of MBM timing. Conclusion: Systemic aCD40 therapy improved survival of MBM-bearing mice, with a shorter interval between s.c. and i.c. implantation; an effect abrogated by later MBM seeding. Systemic aCD40 therapy induced specific changes in the BT infiltrative immune profile, which may explain the distinct response between the early and late BM cohorts. These findings have implications on the experimental modelling of MBM and provide insight into variability of MBM response to immunomodulating therapies. Citation Format: Vinton W. T. Cheng, Victoria R. Breza, Beata Chertok, Natasha D. Sheybani, Timothy N. J. Bullock, Richard J. Price. Timing of melanoma brain metastasis seeding dictates the immunomodulatory effect and efficacy of systemic anti-CD40 agonist therapy [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C030.

Abstract C039: The impact of antiangiogenic therapy on blood vessels and CD8 infiltration in renal cancer metastases is space, time, site, dose, and drug dependent

Abstract Clear cell renal cell carcinoma (ccRCC) is the most prevalent renal neoplasm, with bone as a major site for distant spread in 35% to 40% of the patients. These metastases are typically osteolytic, resistant to treatments, hence result in a variety of skeletal-related complications strongly contributing to mortality. A key feature of ccRCC is the loss of function of the von Hippel–Lindau (VHL) protein leading to extensive angiogenesis. Consequently, different anti-angiogenic tyrosine kinase inhibitors (TKIs) are used as the first or subsequent line of treatment for these patients as single agents or in combination with immune checkpoint inhibitors. However, limited data about their efficacy in bone metastasis is available, and their impact on the immune infiltrate, including effector CD8 cells, is unclear. We hypothesized that TKIs, by inhibiting angiogenesis, significantly reprogram the microenvironment and limit immune infiltration in space, time, dose, and drug dependent fashion. To test these hypotheses, we developed an immunocompetent mouse model of bone metastasis by orthotopical intratibial implantation of luciferase-GFP-positive mouse RENCA-VHL- cell line. Interestingly, intratibial injections gave rise to metastases in lungs, creating a unique opportunity to study two metastatic sites. Three different TKIs currently used in patients were tested and compared to control: axitinib (A), cabozantinib (C), and lenvantinib (L). Outcomes were monitored by macroscopic bioluminescence detection in vivo, 3D multiparametric spatial analysis of bones and lungs, in vivo, and ex vivo. Compared to control-treated mice, high doses of A, C, and L significantly reduced tumor progression in both tumor sites. Even though these TKIs are clinically considered equal, significant differences in their efficacy were noted. Spatial analysis of tumor cells and blood vessels showed a significant decrease in blood vessels formation in both an organ- and TKI-specific pattern over time. Additionally, the reduction of neo angiogenesis in treated tumors directly limited the infiltration of CD8 cells, which localized at the interface with tumor free bone/lung tissue. Interestingly, TKI dose reduction significantly improved CD8 infiltration, while controlling tumor size. TKI withdrawal, instead, led to rapid progression of tumor in both sites and significantly shortened mice survival. In conclusion, we established bone and lung metastatic models of ccRCC and characterized and compared the effects of three antiangiogenic TKIs on angiogenesis and CD8 infiltration. TKIs reduced tumor growth and progression, because of blood vessel formation inhibition. Furthermore, TKI treatment reduced the infiltration of effector T cells in tumors in a dose-dependent manner, an outcome that can have a major impact when TKIs are combined with immunotherapy, a preferential therapeutic regimen for ccRCC patients. Overall, we believe our studies provide important insights and efficacy predictions for innovative therapeutic applications in ccRCC bone metastatic patients. Citation Format: Stefan Maksimovic, Nina Costanza Boscolo, Ludovica La Posta, Matthew T. Campbell, Eleonora Dondossola. The impact of antiangiogenic therapy on blood vessels and CD8 infiltration in renal cancer metastases is space, time, site, dose, and drug dependent [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C039.

Abstract B016: Utilizing gene expression profiles (GEP) to assess tumor microenvironment (TME) and response to immunotherapy

Abstract Background: Despite the success of anti-PD-1/PD-L1 immunotherapies, outcomes for lung cancer patients remain suboptimal. There is a critical need to incorporate multi-omics data focused on the tumor microenvironment (TME) to enhance patient selection and treatment individualization. This study aimed to identify predictive and prognostic biomarkers of immunotherapy response by characterizing transcriptional profiles of lung adenocarcinoma patients who underwent genomic profiling at diagnosis. Methods: RNA sequencing data were obtained from 68 lung adenocarcinoma patients who underwent next-generation sequencing with CARIS at our institution. We analyzed gene expression profiles (GEP) comprising 18 inflammatory genes associated with antigen presentation, chemokine expression, cytolytic activity, and adaptive immune resistance, identified as potential biomarkers for immune checkpoint inhibitor (ICI) response (Cristescu et al., 2018). The genes included were CCL5, CD27, CD274 (PD-L1), CD276 (B7-H3), CD8A, CMKLR1, CXCL9, CXCR6, HLA-DQA1, HLA-DRB1, HLA-E, IDO1, LAG3, NKG7, PDCD1LG2 (PD-L2), PSMB10, STAT1, and TIGIT. GEP scores were calculated, and hierarchical clustering identified tumor subsets with similar GEPs. Gene set variation analysis was conducted to assess enrichment of cell-cell interaction activities of specific ligand-receptor pairs of immune checkpoint genes, partially overlapping with the 18 GEP genes. Results: Hierarchical clustering identified four distinct GEP clusters: "T cell-inflamed GEP," "T cell-non-inflamed GEP high," "T cell-non-inflamed GEP medium," and "T cell-non-inflamed low GEP," with average scores of 0.18 (N=9, 13%), 0.11 (N=29, 43%), 0.08 (N=19, 28%), and 0.04 (N=11, 16%), respectively. The gene scores among these clusters showed significant differences (P = 3.3e-09). Additionally, analysis of specific ligand-receptor pairs of immune checkpoint genes (PD1/PD-L1, PD-L2; CTLA4/CD28, CD80, CD86; ICOS/ICOSLG; TIM3/GAL9; SIRP1/CD47) showed consistent positive enrichment in the “T cell-inflamed” cluster, with no or negative enrichment in the “T cell-non-inflamed” clusters. This suggests active immune checkpoint interactions in clusters with high GEP scores. Conclusion: We identified four different clusters among tissues from patients with NSCLC based on GEP scoring highlighting differences in immune activation and TME makeup, which may play a role in predicting response to immunotherapies. Our results suggest that GEP may provide information on identifying optimal immunotherapeutic approaches based on TME. Our findings underscore the importance of using biomarker-guided strategies to improve patient selection for precision immunotherapy approaches in lung cancer. Citation Format: Changde Cheng, Doug Welsch, Kayla F. Goliwas, Jessy Deshane, Sameer Deshmukh, Sanad Ahlushki, Yanis Boumber, Darshan Shimoga Chandrashekar, Alexander C. Mackinnon, Aakash Desai. Utilizing gene expression profiles (GEP) to assess tumor microenvironment (TME) and response to immunotherapy [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr B016.

Abstract IA025: Targeting the gut microbiome for cancer immunotherapy

Abstract Growing evidence suggests that the gut microbiota modulates the efficacy and toxicity of cancer therapy, most notably immunotherapy and its immune-related adverse effects. The impaired response to immunotherapy in patients treated with antibiotics supports this role of the microbiota. Until recently, results pertaining to the identification of the microbial species responsible for these effects were incongruent, and relatively few studies analyzed the underlying mechanisms. Gut microbial communities (microbiotypes) with non-uniform geographic distribution were associated with favorable and unfavorable outcomes, contributing to discrepancies between cohorts Now, a better understanding of the taxonomy of the species involved and of their mechanisms of action has been achieved. Defined bacterial species have been shown to promote a response to immune checkpoint inhibitors through the production of different products or metabolites, although a suppressive effect of Gram(-) bacteria may be dominant in some unresponsive patients. Machine learning approaches trained on patients’ microbiota composition can predict the ability of patients to respond to immunotherapy with some accuracy. Thus, the interest in modulating the microbiota composition to improve patients’ responsiveness to therapy has been mounting. Our data of a fecal microbiota transfer clinical trial in anti-PD1 refractory melanoma patients has provided clinical proof of concept of the possibility to target the gut microbiota composition in cancer therapy. Also, both in clinical studies and in experimental animals, diets rich in fibers improve the response to immunotherapy by modifying the gut microbiome suggesting the possibility of dietary approaches to target the microbiota composition in cancer therapy. However, while many early clinical studies have analyzed the association of the microbiota composition with the response to anti-PD-1 in cancer patients, emerging evidence suggests that the association may be context dependent and different types of mono or combination immunotherapies may be differentially regulated by the microbiota, Thus, a more personalized approach depending original gut microbiota composition of the patients and the type of immunotherapy protocol selected may be necessary for optimal clinical results. Citation Format: Giorgio Trinchieri. Targeting the gut microbiome for cancer immunotherapy [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr IA025.

Correlation between thyroid dysfunction and efficacy of immune checkpoint inhibitors in patients with advanced solid tumors.

Immune checkpoint inhibitors (ICIs) are currently the first line of tumor immunotherapy for the treatment of a wide range of tumors. However, the main side effect of immune checkpoint inhibitors is that they cause immune-related adverse events (irAEs) in patients. The relationship between the occurrence of immune side effects in patients and efficacy is controversial. The objective of this study was to confirm the relationship between patients who develop thyroid dysfunction after immune checkpoint inhibitors and efficacy. This study was a retrospective real-world clinical study, and a total of 50 patients with advanced tumors treated with immune checkpoint inhibitors at Anqing People's Hospital from 2020.8 to 2022.5 were retrospectively collected. Among them, 30 patients with hypothyroidism and 20 patients with normal or hyperthyroidism occurred, and the treatment effects and prognostic differences between the two groups were compared. After PD1 treatment in all patients, there were 10 cases of partial remission(PR), 18 cases of stable disease(SD) and 2 cases of progressive disease(PD) in patients who developed hypothyroidism, with a disease control rate(DCR) of 93.3% and objective remission rate(ORR) of 33.3%. There were 0 complete remission (CR) patient, 3 PR patients, 11 SD patients, 6 PD patients, 70.0% DCR and 15.0% ORR in patients who did not develop hypothyroidism. The DCR and ORR of patients who developed hypothyroidism were better than those of non-hypothyroid patients, and the difference was statistically significant (P < 0.05). Kaplan-Meier survival analysis showed that progression-free survival (PFS) reached 9.2months (95% CI 7.726-10.779) in patients who developed hypothyroidism and did not hypothyroidism patients have a PFS of 7.3months (95% CI 5.604-8.505), with a statistically significant difference (P = 0.0341 < 0.05). Further subgroup analysis revealed that among patients who developed hypothyroidism, PFS was 3.3months (95% CI 0.630-5.440) in patients with cholangiocarcinoma, 6.89months (95% CI 5.604-8.505) in patients with non-small cell lung cancer, > 12months in patients with hepatocellular carcinoma, and 11.05months (95% CI 9.308-12.792) in patients with esophageal cancer months and PFS for patients with gastric cancer was 9.74months (95% CI 6.979-12.502). When patients with advanced tumors were treated with immune checkpoint inhibitors, DCR and ORR were higher in patients who developed hypothyroidism, and patients had better PFS. The benefits were greater in patients with gastric, esophageal, and hepatocellular carcinomas.

Unexpected Anti-tumor Effect of Selective Internal Radiation Therapy and Radiofrequency Ablation Followed by Immune Checkpoint Inhibitors for Hepatocellular Carcinoma

Introduction: Hepatocellular carcinoma (HCC) has become an increasingly serious health problem worldwide. Combining immune checkpoint inhibitors (ICIs) for HCC with local treatments can produce synergistic effects. Although the abscopal effect was noted in 1953, most studies on this phenomenon have been conducted in the context of external beam radiotherapy (EBRT). The incidence of the abscopal effect induced by selective internal radiation therapy (SIRT) alone is lower. This research reports a case of a patient with multifocal HCC who received SIRT plus radiofrequency ablation (RFA) followed by ICI therapy. During the subsequent course of ICI therapy, an anti-tumor effect was detected in the left hepatic lobe, far from the site targeted by the local treatments. Case Presentation: The abscopal effect has recently attracted widespread attention because ICIs can enhance this phenomenon. However, little is known about the relationship between inducing the abscopal effect and local treatment against HCC. A 76-year-old male patient presented with multifocal HCC. During hepatic angiography, MRI showed multiple HCCs in both lobes of the liver. Selective internal radiation therapy was performed on a tumor with a diameter of approximately 80 millimeters in the right lobe. A month later, RFA was conducted on another tumor in the right lobe, approximately 30 mm in diameter, and ICI therapy was administered on the second day post-RFA. Hepatic arterial phase imaging of contrast-enhanced magnetic resonance performed 10 months after SIRT showed the disappearance of the tumor in the left liver lobe. Conclusions: This case highlights that the combination of multiple local treatment methods with ICI therapy can enhance the anti-tumor immune response and benefit patients with multifocal

Fatal rhabdomyolysis and fulminant myocarditis with malignant arrhythmias after one dose of ipilimumab and nivolumab.

Immune checkpoint inhibitors (ICIs) related myocarditis is a rare complication of modern immunotherapy. It can present as an asymptomatic subclinical condition or full-blown fulminant myocarditis with malignant arrythmias and cardiogenic shock. Myositis/rhabdomyolysis and/or myasthenic symptoms can be present concomitantly. We present a case of fatal fulminant myocarditis presenting with cardiac arrythmias and severe systolic dysfunction, with accompanying rhabdomyolysis after the first dose of ipilimumab and nivolumab immunotherapy. First working diagnosis of subacute late presenting acute myocardial infarction (ACS) was incorrect and the correct diagnosis was established only after additional testing and consultation. Treatment consisted of high-dose corticosteroids, intravenous immunoglobulins, sedation with mechanical ventilation, antibiotic coverage, hemodialysis, and sustained low-efficiency daily diafiltration (SLEDD) with CytoSorb or TheraNova membranes, and intra-aortic balloon pump mechanical cardiac support. No tangible improvement in the condition was observed during the whole treatment period and the patient died on the sixth day of intensive care treatment.

Sex differences in adverse events among cancer patients receiving immune checkpoint inhibitors: the MOUSEION-07 systematic review and meta-analysis.

Immune checkpoint inhibitors have revolutionized cancer treatment, but they are associated with a range of immune-related adverse events (irAEs), and emerging evidence suggests significant sex differences in the incidence, type, and severity of these toxicities, suggesting an influential factor and understanding sex-related differences in irAEs as crucial for optimizing patient care and improving clinical outcomes. In MOUSEION-07 study, we aimed to assess the association between sex and treatment-related adverse events in cancer patients treated with immunotherapy through a large up-to-date meta-analysis of available clinical trials. The present systematic review and meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis. The protocol was registered with PROSPERO no. CRD42024549518. Sixteen studies encompassing a total of 4658 patients were included, and 2133 adverse effects were highlighted. The analysis observed a not statistically significant difference in terms of immune-related adverse events (irAEs) between males and females (Odds Ratio 1.19; CI 0.88-1.63) and revealed the presence of publication bias (β = -2.53; 95% CI = [-4.03; -1.04]; P = 0.006). Sex differences in immunotherapy-related adverse events are a significant factor in cancer treatment, necessitating a personalized approach to patient care. Further research is needed to fully understand the mechanisms driving these differences and to develop optimized strategies for monitoring and managing irAEs in both females and males.

Radiotherapy in patients with brain metastases with and without concomitant immunotherapy: comparison of patient outcome and neurotoxicity.

Recently, immune checkpoint inhibitors (ICI) have been added to the treatment of brain metastases. While combining radiotherapy and ICI can enhance therapeutic effects, it might also increase the risk of severe autoimmune adverse events. This retrospective study aims to compare treatment responses and neurotoxicity in patients treated with radiotherapy alone versus those receiving a combination of radiotherapy and ICI. All patients with brain metastases who received radiotherapy at Hannover Medical School from 2017 to 2019 were included. The medical reports of all study participants were evaluated. Patients who received radiotherapy alone and those who received a combination of radiation and ICI were compared. A total of 248 patients were analyzed, with the most common tumor types being non-small cell lung cancer (NSCLC) and malignant melanoma. Half of the patients received whole-brain radiotherapy (WBRT) and the other half stereotactic radiotherapy (SRT). Of these, 29 patients received concurrent immunotherapy and radiotherapy, 30 completed immunotherapy before radiotherapy, and 29 started ICI after completing radiotherapy. Two cases lacked information on the duration of immunotherapy. Overall survival post-initial tumor diagnosis within the total cohort was 52months, with significantly worse survival for patients with multiple brain metastases (p = 0.020). No significant differences in survival or incidence of neurological adverse events were observed between patients with or without ICI. Combining radiotherapy and ICI did not significantly increase neurotoxicity or improve survival in this cohort, though the heterogeneity of the subgroups limits the generalizability of these findings.

Development of a prognostic signature for overall survival using peripheral blood biomarkers in head and neck squamous cell carcinoma treated with immune checkpoint inhibitors.

We previously reported in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) treated with immune checkpoint inhibitors (ICIs), pretreatment higher lactate dehydrogenase (LDH) and absolute (abx) neutrophils as well as lower percent (%) lymphocytes correlated with worse overall survival (OS). In this study we aimed to develop a prognostic signature for HNSCC treated with ICIs using these peripheral blood biomarkers (PBBMs). Adults with R/M HNSCC treated with ICIs at our institution from 08/2012 to 03/2021 with pretreatment PBBMs were included. Follow-up continued until 02/15/2022. The cohort (n = 151) was randomly split into training (n = 100) and testing (n = 51) datasets. A prognostic score incorporating LDH, % lymphocytes, and abx neutrophils was developed from the training dataset using Cox proportional hazards regression. In the training dataset, a grid search identified the optimal cutpoints classifying patients into high, medium, and low-risk groups (trichotomized signature) as well as high vs. low-risk groups (dichotomized signature). The prognostic score, dichotomized and trichotomized signatures were then validated in the testing dataset. Training and testing datasets showed no clinically meaningful differences in clinicodemographic characteristics or PBBMs. An OS prognostic model was developed from the training dataset: Risk score = 1.24*log10(LDH) - 1.95*log10(% lymphocytes) + 0.47*log10(abx neutrophils). Optimal risk score cutpoints for the dichotomized and trichotomized signatures were defined in the training dataset, and Kaplan-Meier curves for both dichotomized and trichotomized signatures showed good separation between risk groups. Risk scores were calculated in the testing dataset, where the trichotomized signature demonstrated overlap between low and medium-risk groups but good separation from the high-risk group while the dichotomized signature showed clear separation between low and high-risk groups. Higher risk score correlated with worse OS (HR 2.08, [95%CI 1.17-3.68], p = 0.012). Progression-free survival Kaplan-Meier curves likewise showed excellent separation between dichotomized risk groups in the training and testing datasets. We developed a prognostic signature for OS based on 3 previously identified PBBMs for HNSCC treated with ICIs and identified a high-risk group of patients least likely to have survival benefit from ICIs. This signature may improve ICI patient selection and warrants validation in an independent cohort as well as correlation with CPS.

Hepatitis associated with immune checkpoint inhibitors-based combinations of other therapies: A real-world pharmacovigilance analysis based on the FDA adverse event reporting system (FAERS) database.

The combination regimen with immune checkpoint inhibitors (ICIs) and other therapies has been widely applied for patients with non-small-cell lung cancer (NSCLC). To date, no literature has systematically addressed the risk of hepatitis associated with the combination therapy. We conducted this pharmacovigilance analysis using the Food and Drug Administration Adverse Event Reporting System (FAERS). A total of 587,016 NSCLC reports were extracted from FAERS database spanning from the first quarter of 2013 to the second quarter of 2023. After filtering duplicate reports, logistic regression model was used to detect safety signals, and multivariable logistic regression model was used to confirm the interaction between ICI and other drugs. Of the 81,512 patients with NSCLC, 2785 cases developed hepatitis. Multivariable logistic regression analyses revealed that the adjusted ROR of ICI combined with targeted therapy (TT) was the highest 1.64 (95% CI, 1.32-2.02; P < 0.0001) among all therapies, while that of TT and ICI treatment were 1.07 (95% CI, 0.98-1.17; P = 0.1097) and 1.12 (95% CI, 1.03-1.22; P = 0.0111), respectively. The adjusted ROR for the interaction effect was 1.64 (95% CI, 1.32-2.02; P < 0.0001). Furthermore, the adjusted ROR of ICI combined with KRAS-targeted drugs was the highest 3.03 (95% CI, 1.49-5.93; P = 0.0016) among all targeted drugs, with an adjusted ROR of 3.03 (95% CI, 1.49-5.93; P = 0.0016), indicating a meaningful interaction of these two kinds of drugs. We confirmed that combination treatment of ICI and TT is associated with the amplified risk of hepatitis, which is partly due to the interaction between ICI and TT, and the KRAS-targeted drugs may harbor the highest potential for hepatitis induction among TT drugs when combined with ICI. Besides, the combination treatment of ICI- and KRAS-targeted drugs also increases the incidence of colitis, pulmonary embolism and dehydration.

Prognostic Significance of PD-L1 Expression on Circulating Myeloid-Derived Suppressor Cells in NSCLC Patients Treated with Anti-PD-1/PD-L1 Checkpoint Inhibitors

Even though anti-PD-1/PD-L1 immune checkpoint inhibitors (ICIs) in non-small cell lung cancer (NSCLC) have improved survival, a high percentage of patients still do not respond to ICIs. Myeloid-derived suppressor cells (MDSCs) are circulating cells that express PD-L1 and can infiltrate and proliferate in the tumor microenvironment, inducing immunosuppression. By evaluating changes in PD-L1 expression of live peripheral blood MDSCs, we are able to define a new PD-L1 index, useful in predicting ICI escape in NSCLC patients before initiating anti-PD-1/PD-L1 immunotherapy. In this study, a cohort of 37 NSCLC patients was prospectively analyzed, obtaining independent PD-L1 indexes. In patients with a PD-L1 index &gt; 5.88, progressive disease occurred in 58.33% of patients [median progression-free survival (PFS) = 5.73 months; 95%CI = 2.67–20.53], showing significant differences when compared with patients with a PD-L1 index ≤ 5.88, in whom 7.69% progressed and median PFS was not reached (NR); p-value = 0.0042. Overall survival (OS) was significantly worse in patients with a high vs. low PD-L1 index (41.67% vs. 76.92%; median OS = 18.03 months, 95%CI = 6.77–25.23 vs. NR, 95%CI = 1.87-NR; p-value = 0.035). The PD-L1 index can be applied to stratify NSCLC patients according to their probability of response to ICIs at baseline. In addition to quantifying tumoral expression, this index could be used to compare nonresponse to treatment.

Adverse events after nivolumab and ipilimumab combined immunotherapy in advanced renal cell carcinoma: a multicentre experience in Poland.

Immune checkpoint inhibitors (ICIs) have been employed in the adjuvant and metastatic setting of renal cell carcinoma (RCC) treatment. Among ICIs, combined immunotherapy has the highest risk for immune-related adverse events (irAEs). We aimed to document the incidence of irAEs in RCC patients treated with nivolumab and ipilimumab as data from the European population remain limited. We analysed data from 88 RCC patients treated with nivolumab + ipilimumab between May 2022 and June 2024 across six high-volume oncology units in Poland. We reviewed irAEs and estimated their impact on survival parameters via univariate and multivariate Cox proportional hazards regression models, along with log-rank tests. With a median follow-up of 11.3 months, the median overall survival (OS) was not reached, whereas the median progression-free survival (PFS) was 12.8 months (6.3-19.3). A total of 74 irAEs were recorded in 50 patients. The most frequent events were endocrine (n = 20, 27%), hepatic (n = 15, 17%), general (n = 12, 13.6%), and cutaneous (n = 11, 12.5%). The occurrence of irAEs was associated with a 60% lower risk of disease progression (hazard ratio 0.44, 95% confidence interval 0.2-0.87, p = 0.018) without impacting OS and higher disease control rate (n = 45, 90% vs. n = 24, 63.2%, p = 0.004). In contrast, patients with hepatotoxicity had poorer outcomes, with a 2.6-fold greater risk of death (p = 0.05). IrAEs may serve as a predictive factor for the efficacy of the nivolumab + ipilimumab regimen in RCC patients. Special attention is needed for hepatotoxicity, as it can significantly impact survival outcomes.

Subtyping colorectal cancer based on septic shock-associated genes: prognosis and immune characteristics

BackgroundSepsis and colorectal cancer (CRC) are leading causes of death. Given their mutual dependence for susceptibility, we used bioinformatics to explore potential connections between septic shock (SS) and CRC.MethodsWe identified 452 co-expressed genes between SS-related differential expression genes (SS-DEGs) and CRC patient-expressed genes (TCGA-CRC genes). CRC samples were categorized into two cluster subgroups through hierarchical clustering. We then compared the prognosis and immune landscapes of the two cluster subgroups through survival analysis, immune microenvironment analysis, and immune therapy response evaluation.ResultsClustering analysis of the 452 CRC patient-expressed SS-DEGs identified two subtypes: SS-like CRC (SL-CRC) and non-SS-like CRC (NSL-CRC). There were no significant differences in overall survival between the CRC subtypes. However, the subtypes displayed significant differences in immune score, stromal score, and ESTIMATE score. Based on immune therapy databases, there were also significant differences in responses to anti-CTLA-4 and anti-PD-1 immune checkpoint inhibitors between the subtypes.ConclusionOur study reveals significant differences in the immune microenvironment and immune therapy responses between SL-CRC and NSL-CRC subtypes. These findings provide a foundation for identifying new therapeutic targets and developing personalized treatment strategies for specific CRC subtypes.