tbuckley/cabot-search huggingface dataset:
Abstract PR004: Age-induced chronic accumulation of glucocorticoids drives therapy resistance in lung cancer
Authors: Devesh Raizada, Felicia Lazure, Stanislav Drapela, Nadir Sarigul, Joanne Tejero, Didem Ilter, Ana Da Silva Gomes
Journal: Cancer Research (2024)

Abstract Non-small cell lung cancer (NSCLC), a highly aggressive cancer, is the leading cause of cancer- related deaths in the U.S. While chemotherapy and targeted therapy are the main treatment modalities in the clinic, many patients do not respond to these treatments. Strikingly, the median age for lung cancer diagnosis is 71. Yet, preclinical and clinical research have largely been skewed towards young mice and patients. Here, we address this gap in knowledge and evaluate if old age affects the response to standard of care NSCLC therapies in KRAS-driven NSCLC. Using human sera from young and old healthy subjects to treat NSCLC cell lines, we show that age-driven circulatory changes are sufficient to drive a state of profound resistance to both chemotherapies as well as KRASG12C targeted therapies. We confirmed the relevance of our findings in vivo, by transplanting cancer cells derived from the K-rasLSL-G12D/+; p53fl/fl genetically engineered mouse model of lung cancer into young and old C57BL/6 mice. Using this model we showed that unlike young lung tumor-bearing mice on chemotherapy, old tumor-bearing mice do not respond to treatment and have a poor prognosis. Mechanistically, we found that old age drives a transcriptional reprogramming that favors drug resistance and identified the glucocorticoid receptor as a major driver of these transcriptional changes. We traced this to an age-induced chronic accumulation of glucocorticoids in circulation and within the tumor interstitial fluid. Chronic treatment with age-relevant concentrations of cortisol alone was sufficient to drive glucocorticoid receptor activation and induce resistance to therapies mirroring the effects of old age. Further supporting a driving role for glucocorticoids in driving age- induced drug resistance, blocking the glucocorticoid receptor genetically or pharmacologically rescues the drug resistance state imposed by old age in NSCLC cells. Lastly, using TCGA patient data we show an inverse correlation between glucocorticoid receptor activation (GR score) and progression-free survival of lung cancer patients. Together, our work demonstrates a role for age-induced glucocorticoids in circulation in promoting therapy-resistance in NSCLC patients and supports the use of therapeutic agents that block the glucocorticoid receptor as a strategy to increase therapy efficacy in NSCLC patients. Citation Format: Devesh Raizada, Felicia Lazure, Stanislav Drapela, Nadir Sarigul, Joanne Tejero, Didem Ilter, Ana Da Silva Gomes. Age-induced chronic accumulation of glucocorticoids drives therapy resistance in lung 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 PR004.
Abstract C040: Spatial transcriptomics unveils disparities in tumor microenvironment dynamics between breast cancer responders and non-responders
Authors: Jeremy Mo, Hanyun Zhang, Kate Harvey, Alexander Swarbrick
Journal: Cancer Research (2024)

Abstract Spatial transcriptomics is revolutionizing our understanding of cellular dynamics and interactions in the tumor microenvironment (TME). By mapping distinct cellular populations and their interactions, we can gain valuable insights into tumor behavior. To investigate these dynamics in breast cancer, we conducted Xenium In-situ spatial transcriptomics on twenty formalin-fixed paraffin-embedded (FFPE) samples taken from eight patients undergoing neoadjuvant chemotherapy. These samples have been taken pre-treatment, mid-treatment and post-treatment from four cases with pathological complete response (pCR), and four cases with residual disease (RD) at time of surgery. Our analyses have found distinct cellular composition changes between pCR and RD cases. Patients with RD demonstrated an increase in endothelial, perivascular-like (PVL) and epithelial cells from pre- to post-treatment. This was accompanied by a decrease in myeloid and malignant epithelial cells at mid-treatment. In contrast, patients with pCR demonstrated increases in cancer-associated fibroblasts (CAFs) and myeloid cells, with reductions in plasmablasts and cancer epithelial cells at mid-treatment. This suggests that an increase in CAF and myeloid cells observed between pre-treatment and mid-treatment samples may be predictive of response. We performed ligand-receptor (LR) analyses, which demonstrated diverse myeloid interactions in RD cases and diverse CAF interactions in pCR cases in pre-treatment samples. Mid-treatment samples exhibited a decrease in interactions for CAFs, myeloid and T cells in pCR and RD cases. The most frequently identified CAF LR interactions, as senders, were between TGFB1/TGFB3 and TGFBR1/TGFBR2, while the most frequently identified myeloid LR interactions were between PDCD1LG2 - PDCD1 (encoding PDL2 &amp; PD1), CCL8 - ACKR1 (encoding Atypical Chemokine Receptor 1) and CCL2 - ACKR1. Our findings indicate that the dynamic changes in cellular composition and interactions within the TME differs between responders and non-responders. To further explore these differences, we plan to perform spatially constrained analyses to identify unique cellular niches that may serve as potential biomarkers for informing novel therapeutic strategies. Citation Format: Jeremy Mo, Hanyun Zhang, Kate Harvey, Alexander Swarbrick. Spatial transcriptomics unveils disparities in tumor microenvironment dynamics between breast cancer responders and non-responders [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 C040.
Abstract IA019: Regulation of EMT tumor states by stromal cells
Authors: Cédric Blanpain
Journal: Cancer Research (2024)

Abstract Epithelial-to-mesenchymal transition (EMT) is a reversible process during which epithelial cells lose their epithelial characteristics and acquire mesenchymal features, that are important for tumor initiation, progression, stemness, metastasis, and therapy resistance. Different EMT states, each with distinct functional properties, have been identified across various tumor models. These EMT states reside within specific physical niches, characterized by unique stromal cell populations. Understanding the cellular interactions within the tumor microenvironment (TME) and their influence on EMT could lead to novel therapeutic strategies. To understand how the TME regulates the distinct tumor states, we performed single-cell RNA sequencing of the tumor cells and their TME in mouse cancer models presenting EMT. We identified distinct subsets of cancer-associated fibroblasts (CAFs), macrophages, neutrophils, endothelial cells, pericytes, adipocytes, dendritic cells, mast cells, Schwann cells, and T cells in different tumor types. To unravel how TME-tumor cell interactions regulates EMT, we used different bioinformatic approaches to identify ligand-receptor pairs that are likely to organize the tumor niche and to regulate tumor transition states. In vitro treatment of tumor cells with some of these ligands demonstrated their EMT-promoting effects. These findings provide novel mechanistic insights on the crosstalk between tumor cells and the surrounding TME, that may have important implications for anti-cancer therapy. Citation Format: Cédric Blanpain. Regulation of EMT tumor states by stromal cells [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 IA019.
Abstract PR009: FMRP upregulation in cancer: Implicating FMRP-expressing cancer-associated fibroblasts in immune evasion
Authors: Simge Yucel, Nadine Fournier, Mireia Blanco Gomez, Douglas Hanahan
Journal: Cancer Research (2024)

Abstract Our research has uncovered a novel and significant role for Fragile-X-mental-retardation-protein (FMRP) in cancer biology, extending its well-established functions beyond neuronal development. In a recent Science publication (Zeng et al., 2022), we demonstrated that elevated FMRP levels drive immune evasion in various murine and human tumors by modulating immune cell subsets, particularly through the suppression of effector T-cells. To further elucidate the mechanisms of FMRP-mediated immune evasion, we investigated its influence on the stromal component of the tumor microenvironment. Single-cell RNA sequencing of pancreatic ductal adenocarcinoma (PDAC) tumors revealed cancer-associated fibroblasts (CAFs) as the primary stromal cell subtype expressing FMRP. Given the crucial roles that CAFs play in tumor progression and therapeutic resistance, we explored whether FMRP expression contributes to the immunosuppressive characteristics of CAFs in PDAC and breast tumors. Our findings reveal that FMRP expression is markedly upregulated in CAFs from both breast and PDAC tumors, in contrast to its absence in naïve fibroblasts from healthy tissues. Knockdown of FMRP in CAFs resulted in substantial changes in their myofibroblastic and inflammatory properties, while overexpression of FMRP in naïve fibroblasts was sufficient to induce a CAF-like phenotype. Notably, FMRP overexpression led to significantly elevated inflammatory CAF (iCAF) and myofibroblastic CAF (myCAF) signatures, highlighting its role as a key pan-CAF regulator that influences both extracellular matrix (ECM) modulation and the secretory phenotype of CAFs. We utilized the full-body knockout (KO) mice model of the Fmr1 gene, which encodes FMRP, to further delineate the functional importance of FMRP expression in CAFs in stimulating an immunosuppressive program in vivo. Through bulk RNA sequencing, we developed an FMRP- associated gene signature for CAFs and applied it to human datasets, where we observed a pronounced increase in FMRP signatures in CAFs from human PDAC and breast tumors, highlighting its translational relevance. In conclusion, our research underscores the pivotal role of FMRP in cancer biology, impacting both the immune and stromal components of the tumor microenvironment. Targeting FMRP, particularly within CAFs, emerges as a promising therapeutic strategy to improve cancer treatment outcomes. Citation Format: Simge Yucel, Nadine Fournier, Mireia Blanco Gomez, Douglas Hanahan. FMRP upregulation in cancer: Implicating FMRP-expressing cancer-associated fibroblasts in immune evasion [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 PR009.
Abstract PR001: An immunomodulatory crosstalk between cancer cells and the hepatic microenvironment underlies mutant estrogen receptor-driven breast cancer-to-liver metastasis
Authors: Sunny Das, Joana Liu Donaher, Lisa Verhoeven, Ranjan Mishra, Ferenc Reinhardt, Sumeet Gupta, Zheqi Li, Kornelia Polyak, Robert A. Weinberg
Journal: Cancer Research (2024)

Abstract While major advancements have been made in treatment of primary tumors in estrogen receptor-positive (ER+) breast cancer, reducing mortality from metastatic breast cancer (mBC) in treated patients who develop endocrine resistance to first line therapies remains an unmet clinical need. Wild-type ER activity or availability of its cognate ligand 17-beta estradiol (E2) are major factors in primary tumor progression, which are lost/reduced due to endocrine treatments, such as use of selective estrogen degraders (SERDs) and aromatase inhibitors (AIs), respectively. Over time, this leads to selection of rare cancer cells bearing point mutations in ESR1, the gene encoding ER-alpha, which become the dominant population at metastatic sites, and such mutations are now recognized as a frequent driver of endocrine resistance and metastasis, especially in patients with advanced ER+ breast cancer who have been heavily pre-treated with AIs. Analyses of clinical samples have shown a statistically significant association enrichment of ESR1 mutations in liver metastases, compared to the primary tumor. Other distant tissues commonly colonized by breast cancer cells, such as bones, lungs, or brain, although prevalent, do not display this strong association. While this might be due to ease of biopsy sampling in the liver compared to other sites, an alternate and intriguing hypothesis is that the liver offers a fertile soil for metastatic colonization by mutant ER-expressing cells, compared to other distant sites, such as lungs. Using a combination of pre-clinical models, we assessed if mutant ER could drive metastatic colonization at distant sites, such as the liver. We have uncovered a novel link between cancer cell-intrinsic immunomodulatory signaling pathways that are specifically upregulated in mutant ER-expressing breast cancer cells, which represents at least one major molecular mechanism underlying the observed liver tropism of mutant ER-associated, endocrine resistant ER+ breast cancer. We show that disseminated, mutant ER-expressing BC cells engage in crosstalk with the liver stromal and immune populations post-extravasation to further fuel metastatic outgrowth. Citation Format: Sunny Das, Joana Liu Donaher, Lisa Verhoeven, Ranjan Mishra, Ferenc Reinhardt, Sumeet Gupta, Zheqi Li, Kornelia Polyak, Robert A. Weinberg. An immunomodulatory crosstalk between cancer cells and the hepatic microenvironment underlies mutant estrogen receptor-driven breast cancer-to-liver metastasis [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 PR001.
Abstract C020: Discovery &amp; characterization of small molecules to enhance Natural Killer cell cytotoxicity against solid tumors
Authors: Indrani Das, Olubukola Abiona, Riufu Liu, Grace K. Lee, David N. Wald
Journal: Cancer Research (2024)

Abstract While adoptive cellular therapies (ACT) such as CAR-T and NK therapy have shown clinical efficacy against hematologic malignancies, their use against solid tumors (such as ovarian or pancreatic cancer) has had limited success to date. In particular, CAR-T therapy for solid cancers has led to severe toxicities, including on-target, off-tumor killing of healthy cells and graft vs. host disease (GVHD) with allogeneic transplant. NK cell therapies, in contrast, have fewer associated toxicities due to specific and innate recognition/killing of cancer cells. This greater safety profile makes NK therapies an attractive treatment option for solid cancers. NK therapies are currently limited by insufficient in vivo tumor clearance, caused largely by their lower cytotoxicity and in vivo expansion compared to CAR-T cells. To address this, we have screened 300,000 small molecule compounds for their ability to enhance NK cytotoxicity against ovarian cancer (OVCAR) cells. Our primary screen identified 11 lead compounds which increase NK killing activity against OVCAR cells &amp;gt;= 10% over baseline (vehicle-treated control). Secondary in vitro assays have confirmed that at least 3 out of 11 lead compounds enhance NK cytotoxicity by at least 10% over baseline. As such, we hypothesize that our lead compounds will increase in vivo NK cytotoxicity and tumor clearance, through mechanisms which might include I) upregulation of NK activating receptors, II) downregulation of NK inhibitory receptors, and/or III) modulation of NK metabolism in the immunosuppressive tumor microenvironment. Immediate future studies include in vivo testing of our lead compounds’ ability to enhance NK cytotoxicity, using immunodeficient mouse models of subcutaneous OVCAR tumors. Moreover, we will utilize 2D and 3D in vitro culture techniques alongside flow cytometry and RNA sequencing to identify how lead compounds impact markers of NK activation and metabolism. This will include expression of activating/inhibitory receptors, exhaustion markers, and key metabolic factors. Finally, we will assess the effect of lead compounds on NK function within an immunosuppressive tumor environment. Our findings will contribute to effective future NK cell therapies for solid tumors. Citation Format: Indrani Das, Olubukola Abiona, Riufu Liu, Grace K. Lee, David N. Wald. Discovery &amp; characterization of small molecules to enhance Natural Killer cell cytotoxicity against solid tumors [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 C020.
Abstract B042: The impact of opioids on the pancreatic tumor immune microenvironment
Authors: Kathryn Maraszek, Michael Feigin
Journal: Cancer Research (2024)

Abstract Pancreatic cancer is a highly lethal malignancy with a 5-year survival rate of 12.8%. Due to the high prevalence of cancer-related pain, 75% of pancreatic cancer patients are prescribed opioids. Opioids, which signal through the G protein-coupled receptor (GPCR) mu-opioid receptor (MOR), have peripheral effects outside of their analgesic function. Importantly, several studies have correlated opioids with worsened survival of patients receiving immunotherapy. However, the mechanism behind this is unknown. Immunotherapy is largely ineffective in pancreatic cancer, due in part to the tumor microenvironment (TME) characterized by dense, desmoplastic stroma, with cancer-associated fibroblasts (CAFs) comprising up to 90% of the tumor volume. CAFs play a large role in immunosuppression and therapy resistance, such as through promoting infiltration of immunosuppressive cells, resulting in reduced presence of antitumor immune cells and impaired immunotherapy efficacy. While the role of CAFs in promoting immunosuppression in the tumor microenvironment is well characterized, the effect of opioids on this phenomenon is unknown. We now provide evidence that MOR directly regulates CAF function. Specifically, knockdown of MOR in CAFs reduces gene expression of alpha-smooth muscle actin (aSMA) and leukemia inhibitory factor. MOR knockdown in CAFs also decreases protein expression of aSMA and type 1a collagen. We hypothesize that opioids promote MOR-dependent CAF activation and secretion of pro-inflammatory cytokines, resulting in a more immunosuppressive TME, and thus impaired immunotherapy response. The long-term goal of this work is to determine the role of opioids on CAFs in the pancreatic TME, as well as the role of MOR in promoting immunosuppression and the resulting value of MOR as a target to improve immunotherapy efficacy. This research is clinically significant because it could uncover a novel mechanism driving immunosuppression caused by a medication commonly prescribed to almost all pancreatic cancer patients. Citation Format: Kathryn Maraszek, Michael Feigin. The impact of opioids on the pancreatic tumor immune microenvironment [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 B042.
Abstract A019: Increased vulnerability of colorectal cancer with high alkylation damage to NTHL1 inactivation
Authors: Hyeoncheol Kim, Jules Cazaubiel, Tung-Lin Chiang, Carino Gurjao, Samantha Fitzgerald, Marios Giannakis
Journal: Cancer Research (2024)

Abstract Background: NTHL1 is a DNA glycosylase, and mutations in this gene are linked to colorectal polyps and colorectal cancer (CRC). SBS30, a mutational signature associated with NTHL1 inactivation, correlates with c-alkylation (c-alkyl), a CRC mutational signature of alkylating damage. We aimed to investigate the potential for synthetic lethality between c-alkyl and NTHL1 inactivation as a novel therapeutic strategy for CRC. Methods: Using DepMap data, we categorized CRC cell lines into low and high c-alkyl groups. We performed CRISPR-mediated NTHL1 knockouts (KOs) in high vs low c-alkyl groups of cell lines and patient-derived CRC organoids and tested for synthetic lethality and its mechanisms. Results: High c-alkyl cells with NTHL1 KO showed decreased proliferation compared to low c-alkyl cells, with cell cycle arrest predominantly in the G2/S phase. Treatment with N-Nitroso-N-methylurea (MNU, alkylating reagent) converted low c-alkyl cells to a high c-alkyl state and conferred increased susceptibility to NTHL1 KO. High c-alkyl patient-derived organoids similarly showed lower proliferation with NTHL1 KO compared to low c-alkyl ones. High c-alkyl cells exhibited increased DNA damage, indicated by γH2AX and CHK1 phosphorylation. Low c-alkyl cells exhibited significant HDAC1 and HDAC2 upregulation, which was not seen in high c-alkyl cells. This could explain their protection against NTHL1 KO, whereas the lack of change in HDAC protein level may explain the failure of high c-alkyl cells to repair NTHL1-induced DNA damage. High c-alkyl cells with NTHL1 KO additionally showed increased DNA damage and cell death when treated with checkpoint inhibitors AZD-7762, LY2606368, and Rabusertib. Conclusions: NTHL1 KO presents a promising therapeutic target, especially for high c-alkyl CRCs that are more susceptible to DNA damage. Our findings also suggest that combining NTHL1 inhibition with CHK1 inhibition may offer new therapeutic opportunities in CRC. Citation Format: Hyeoncheol Kim, Jules Cazaubiel,, Tung-Lin Chiang, Carino Gurjao, Samantha Fitzgerald, Marios Giannakis. Increased vulnerability of colorectal cancer with high alkylation damage to NTHL1 inactivation [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 A019.