tbuckley/cabot-search huggingface dataset:
Abstract 5559: The anti-tumor efficacy and immune effects of combining of ceralasertib, an oral ATR kinase inhibitor, with imipridones, in prostate cancer treatment <i>in vitro</i> and <i>in vivo</i>
Authors: Yutong Linda Xia, Leiqing Zhang, Maryam Ghandali, Maximilian P. Schwermann, Wafik El-Deiry
Journal: Cancer Research (2024)

Abstract Prostate cancer is the most common cancer and the second leading cause of cancer death among men in the United States. There is an estimated 10% to 50% of cases progress to metastatic castration resistant prostate cancer (mCRPC) state within 3 years of diagnosis. mCPRC remains lethal despite therapeutic advances. There is approximately 20% of mCRPC patients present somatic DNA damage repair (DDR) gene mutations. Ceralasertib, formerly known as AZD6738, is a potent and selective orally bioavailable inhibitor of the ataxia tenlangiectasia and Rad3-related (ATR) kinase, which is involved in DNA repair in response to DNA damage and replication stress. Preclinical studies have demonstrated ATRi sensitizing alterations in DNA damage response (DDR) genes. Ceralasertib’s antitumor activity as a monotherapy in treating prostate cancer is moderate. Thus, we combined ceralasertib with imipridones (ONC201 and ONC206), which target mitochondrial caseinolytic protease P (ClpP) and the integrated stress response, resulting in enhanced antitumor efficacy in vitro. Prior data have demonstrated sensitivity of 4 prostate cancer lines to ceralasertib and imipridones monotherapies, synergistic activities with the combination treatments, and immune enhancement effects with the combination treatments when co-cultured with NK92MI cell line. We proceeded to a short term in-vivo study validating the combination treatment efficacy. Preliminary results include cytokine profiling using the Luminex 200 technology to understand treatment induced changes in the tumor microenvironment (TME) from both in vitro and in vivo studies. Our results guide novel clinical trials for effective clinical responses in mCPRC patients. Citation Format: Yutong Linda Xia, Leiqing Zhang, Maryam Ghandali, Maximilian P. Schwermann, Wafik El-Deiry. The anti-tumor efficacy and immune effects of combining of ceralasertib, an oral ATR kinase inhibitor, with imipridones, in prostate cancer treatment in vitro and in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5559.
Abstract 3971: Progesterone impacts regulatory T cell activity to promote immunosuppression in the mammary gland
Authors: Eilidh I. Chowanec, Lauryn R. Werner, Christy R. Hagan
Journal: Cancer Research (2024)

Abstract Estrogen and progesterone signaling together drive hormone-receptor positive breast cancer growth and progression. However, there have been limited studies on the independent role that progesterone and its receptor, the progesterone receptor (PR), play in the development of breast cancer. Studies in the Hagan lab have shown that progesterone signaling promotes mammary tumor growth and changes the immune landscape of the mammary gland towards immunosuppression. Regulatory T-cells (Tregs) are immune cells known to promote immunosuppression in the tumor microenvironment. The data from our lab shows that among hormone receptor positive breast cancers, higher levels of PR expression correlates to higher levels of Tregs in the tumor microenvironment. To determine if progesterone signaling increases the number of Tregs in the tumor-bearing mammary gland, we used a syngeneic orthotopic murine tumor model, E0771 cells, engineered to express mouse PR or control empty vector. Mice were treated with progesterone or placebo for 7 days before implantation of the modified E0771 cells. The results of this study show that progesterone promoted tumor growth, and flow cytometry analysis at tumor endpoint showed that PR-positive tumors treated with progesterone harbored more Tregs than mice treated with placebo. Additionally, initial studies using flow cytometry and RNA-seq indicate increased Treg activity following progesterone treatment in PR+ tumor-bearing mice. As progesterone treatment promoted tumor growth and Treg recruitment in progesterone receptor-positive tumors, these data imply that progesterone treatment may promote the release of secreted factors impacting the immune cells in the mammary microenvironment. To determine if progesterone treatment results in cytokine or chemokine changes that may affect Treg recruitment, cytokine arrays and enzyme-linked immunosorbent assays (ELISAs) were performed using cell culture supernatant from murine mammary tumor cells expressing progesterone receptor (E0771-PR) treated with progesterone (0-72 hours). E0771-PR cells treated with progesterone showed higher levels of cytokines and chemokines that have been linked to Treg recruitment and differentiation, such as MCSF. Our findings demonstrate that progesterone signaling promotes an immune suppressed microenvironment in the mammary gland through an increase in Tregs. This evidence provides rationale to investigate the use of anti-progestins as a mechanism to overcome the immune-cold tumor microenvironment seen in progesterone receptor positive breast tumors. Citation Format: Eilidh I. Chowanec, Lauryn R. Werner, Christy R. Hagan. Progesterone impacts regulatory T cell activity to promote immunosuppression in the mammary gland [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3971.
Abstract 1901: Disitamab vedotin, a clinical stage HER2-directed antibody-drug conjugate, shows potent antitumor activity as a monotherapy in preclinical urothelial cancer models
Authors: Renee Hein, Kelsi Willis, Gina LoMastro, Suhas Vasaikar, Vinita Gupta, Katie Snead, Sharsti Sandall, Anita Kulukian
Journal: Cancer Research (2024)

Abstract Disitamab vedotin (DV, RC48-ADC) is an antibody-drug conjugate (ADC) that selectively delivers cytotoxic drug to HER2-expressing cancer cells. DV is composed of disitamab, a HER2-directed monoclonal antibody, and a vedotin linker-payload system, which enables conjugation of the microtubule-disrupting agent monomethyl auristatin E (MMAE) to the antibody via a protease-cleavable linker. The proposed mechanism of action (MOA) of DV occurs through direct cytotoxicity of HER2-expressing tumor cells following internalization of DV and intracellular release of MMAE. DV may also induce antitumor activity through bystander-mediated cytotoxicity of neighboring cells and via the inhibition of HER2 signaling pathways. Moreover, cellular response to MMAE includes the induction of immunogenic cell death and recruitment of immune cells to the tumor site. DV is currently being evaluated globally in subjects with HER2-expressing locally advanced or metastatic urothelial carcinoma (la/mUC) and has gained conditional approval in China following an overall response rate of 50.5% (pooled analysis from studies NCT03507166 and NCT03809013). RNA sequencing data from a large cohort of urothelial cancer patient tumors revealed expression of HER2 in many urothelial tumors; however, the relationship between HER2 expression and efficacy of DV is not well understood. Here, we sought to evaluate the antitumor activity of DV monotherapy in preclinical urothelial cancer models with varying levels of HER2 expression. Multiple patient-derived xenografts (PDX) and patient-derived 3D in vitro urothelial cancer models showed potent antitumor response to DV monotherapy in tumors with varying HER2 expression levels including HER2-low tumors. Overall, these findings support ongoing clinical trials in subjects with HER2-expressing la/mUC and provide scientific rationale to further explore DV monotherapy in HER2-positive and HER2-low urothelial cancer clinical settings. Citation Format: Renee Hein, Kelsi Willis, Gina LoMastro, Suhas Vasaikar, Vinita Gupta, Katie Snead, Sharsti Sandall, Anita Kulukian. Disitamab vedotin, a clinical stage HER2-directed antibody-drug conjugate, shows potent antitumor activity as a monotherapy in preclinical urothelial cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1901.
Abstract 470: AR-induced miRNA124-3p.2 suppresses the metastasis-promoting factor CCL2
Authors: Shuhei Aoyama, Kouji Izumi, Atsushi Mizokami
Journal: Cancer Research (2024)

Abstract Objective: The standard treatment for advanced prostate cancer is androgen deprivation therapy that blocks androgen receptor (AR) signaling, but this therapy becomes ineffective within a few years, resulting in castration-resistant prostate cancer. We have previously shown that blockade of AR signaling induces CCL2 and activates cancer cells through an autocrine mechanism, but why AR blockade induces CCL2 secretion has not been elucidated. Micro RNAs (miRs) are endogenous non-coding RNAs that regulate the translation of various proteins. In this study, we investigated whether miRs are involved in CCL2 induction. Subjects and Methods: We used miRNA PCR Plate Array and Target Scan (https://www.targetscan.org) to search for miRs that are controlled by AR and bind to and repress the CCL2 gene. We knocked down the AR of human prostate cancer cell lines LNCaP and C4-2B with siRNA (siAR) and examined the expression of target miRs and CCL2. siAR-transfected LNCaP and C4-2B were transfected with target miR mimic and CCL2 expression was examined. siAR-transfected LNCaP, C4-2B, and C4-2B were transfected with target miR mimic and CCL2 expression was examined. siAR-transfected LNCaP and C4-2B were transfected with target miR mimic and CCL2 expression was examined. The target miR mimic was introduced into them, and the changes in migration ability were evaluated. Results: miR-124-3p.2 was extracted as a candidate from miRNA PCR Plate Array and Target Scan. miR-124-3p.2 expression was upregulated in both LNCaP and C4-2B when DHT was added and downregulated when CCL2 was added. In siAR LNCaP and C4-2B, the expression of CCL2 was decreased when miR-124-3p.2 mimic was introduced. Furthermore, in siAR-transfected LNCaP, C4-2B, the introduction of miR-124-3p.2 mimic suppressed the migration. Conclusion: AR suppresses CCL2 via miR124-3p.2. miR124-3p.2-mediated regulation of CCL2 may be a new therapeutic target for advanced prostate cancer. Citation Format: Shuhei Aoyama, Kouji Izumi, Atsushi Mizokami. AR-induced miRNA124-3p.2 suppresses the metastasis-promoting factor CCL2 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 470.
Abstract 5564: The regulation of PD-L1 in glioblastoma cells involves Pyk2 signaling
Authors: Tyrel Porter, Lilia Kucheryavykh
Journal: Cancer Research (2024)

Abstract Glioblastoma (GBM), the most aggressive brain cancer which is usually fatal within a year after diagnosis, poses a significant therapeutic challenge with conventional treatments providing limited success. Despite advancements in immune checkpoint blockade, PD-L1 inhibitors exhibit suboptimal efficacy in recurrent GBMs with recent clinical trials demonstrating only 8% objective responses in patients. Utilizing the R2 Genomic Analysis Visualization Platform, we identified a positive 8-18% correlation between Pyk2 and PD-L1 gene expression in human GBM specimens. We hypothesize that Pyk2 signaling is involved in the regulation of PD-L1 expression in GBM cells. In this study, primary human glioblastoma cell lines and GL261 mouse glioma cells were assessed employing CRISPR/Cas9 Pyk2 knockout (Pyk2KO) combined with pharmacological Pyk2 inhibition. Flow cytometric analysis revealed a 35% decrease in PD-L1 expression in Pyk2KO GL261 cells compared to wild-type cells. SiRNA knockdown against Pyk2 in primary human GBM cells demonstrated a similar response, with a 50% decrease in PD-L1 expression compared to MOCK control cells. Additionally, the application of the Pyk2/FAK inhibitor defactinib at a concentration of 0.2 μM reduced PD-L1 expression by 32% in both GL261 and primary human GBM cells. These findings highlight Pyk2 as a potential therapeutic target for modulating the immunosuppressive microenvironment in GBM and enhancing the effectiveness of immune checkpoint blockade therapies. This study was supported by: NIH Grant 1SC1GM122691 and PRSTRT2022. Citation Format: Tyrel Porter, Lilia Kucheryavykh. The regulation of PD-L1 in glioblastoma cells involves Pyk2 signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5564.
Abstract 5530: Metastasis founder cells activate immunsuppression early in human metastatic colonization
Authors: Severin Guetter, Courtney Koenig, Huiqin Koerkel-Qu, Aleksandra Markiewicz, Sebastian Scheitler, Marie Katzer, Mark Berneburg, Philipp Renner, Beatrix Cucuruz, Leonhard Guttenberger, Veronika Naimer, Kathrin Weidele, Steffi Treitschke, Christian Werno, Hanna Jaser, Tonia Bargmann, Armin Braun, Florian Weber, Katharina Limm, Reinhard Rachel, Felix Baumann, Lisa Schmidleithner, Kathrin Schambeck, Anja Ulmer, Sebastian Haferkamp, Christoph Klein, Melanie Werner-Klein
Journal: Cancer Research (2024)

Abstract Metastatic dissemination occurs very early in melanoma, often before diagnosis, rendering prevention of metastasis formation an important therapeutic goal. However, the earliest steps of lethal metastasis in patients are incompletely understood. Therefore, in this study we searched for the earliest detectable disseminated cancer cells (DCC) in sentinel lymph node biopsies of 492 stage I-III melanoma patients. We used micromanipulator-assisted isolation and single-cell transcriptome analysis of these extremely rare DCC and identified melanoma -associated chondroitin sulfate proteoglycan (MCSP) expressing melanoma cells as strong candidates for metastasis founder cells in lymph nodes. Based on a median follow-up time of 6 years, their detection was the strongest predictor of systemic metastasis and death upon multivariable analysis. Single-cell transcriptome analysis revealed that melanoma DCC were exposed to CD8 T cell attack during the transition from single cells to metastasis-initiating clusters, activated the extracellular vesicular exosomal pathway, and expressed the immunomodulatory proteins CD155 and CD276, but rarely PD-L1. CD155- and CD276-positive extracellular vesicles from patient-derived DCC models showed an immunosuppressive activity on CD8 T cells. In conclusion, our data suggest that either direct targeting of metastasis-founder cell with MCSP or their immune escape mechanisms may be key to curing early-stage melanoma. Citation Format: Severin Guetter, Courtney Koenig, Huiqin Koerkel-Qu, Aleksandra Markiewicz, Sebastian Scheitler, Marie Katzer, Mark Berneburg, Philipp Renner, Beatrix Cucuruz, Leonhard Guttenberger, Veronika Naimer, Kathrin Weidele, Steffi Treitschke, Christian Werno, Hanna Jaser, Tonia Bargmann, Armin Braun, Florian Weber, Katharina Limm, Reinhard Rachel, Felix Baumann, Lisa Schmidleithner, Kathrin Schambeck, Anja Ulmer, Sebastian Haferkamp, Christoph Klein, Melanie Werner-Klein. Metastasis founder cells activate immunsuppression early in human metastatic colonization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5530.
Abstract 4474: Novel analogs of 4-substituted pyrrolo[2,3-<i>d</i>]pyrimidines as dual-targeted mEGFR/AURKA inhibitors for lung cancer
Authors: Sonali Kurup, Gabe Carpenter, Samantha Satawa, Felix Amissah, Erika Lisabeth, Matthew Giletto, Edmund Ellsworth
Journal: Cancer Research (2024)

Abstract Small molecule, mutant epidermal growth factor receptor kinase (mEGFR) inhibitors such as osimertinib and erlotinib constitute the recommended therapy for mEGFR-positive non-small cell lung cancer (NSCLC). However, mEGFR inhibitors are ineffective in NSCLC over time due to mutations within mEGFR and redundant signaling pathways such as mutant KRAS (mKRAS) that bypass mEGFR inhibition. Simultaneous inhibition of multiple kinases has been suggested to provide synergistic effects on tumor growth inhibition and tumor resistance. Studies have shown that resistance to mEGFR inhibitors was overcome when mEGFR inhibitors were combined with aurora kinase (AURK) inhibitors. Additionally, mEGFR inhibitors were found to retain their anticancer effects in mKRAS-positive NSCLC cells if given concurrently with AURK inhibitors. Kurup et al. previously reported a series of 4-substituted pyrrolo[2,3-d]pyrimidines as dual mEGFR/AURKB inhibitors. Novel analogs of 1-5 have been designed to incorporate AURKA inhibition while maintaining mEGFR inhibition. Molecular modeling was utilized to guide selectivity for AURKA over AURKB. This study led to the identification of novel dual-targeted mEGFR/AURKA inhibitors with demonstrated inhibition of mKRAS+ NSCLC and mEGFR+ NSCLC. The design, synthesis, kinase inhibitory activities, and anticancer effects for these novel analogs will be presented. Structure-activity relationships for dual mEGFR/AURKA inhibition will be defined. Citation Format: Sonali Kurup, Gabe Carpenter, Samantha Satawa, Felix Amissah, Erika Lisabeth, Matthew Giletto, Edmund Ellsworth. Novel analogs of 4-substituted pyrrolo[2,3-d]pyrimidines as dual-targeted mEGFR/AURKA inhibitors for lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4474.
Abstract 2487: KRAS and TP53 co-mutation predicts benefit of immune checkpoint blockade in lung adenocarcinoma
Authors: Jan Budczies, Eva Romanovsky, Martina Kirchner, Olaf Neumann, Miriam Blasi, Johannes Schnorbach, Rajiv Shah, Farastuk Bozorgmehr, Rajkumar Savai, Thorsten Stiewe, Solange Peters, Peter Schirmacher, Thomas Michael, Daniel Kazdal, Petros Christopoulos, Albrecht Stenzinger
Journal: Cancer Research (2024)

Abstract PD-L1 protein expression is the most important predictive biomarker for immune checkpoint inhibition (ICI) in advanced non-small cell lung cancer (NSCLC), but has limited sensitivity and specificity. We analyzed the potential of activating KRAS and pathogenic TP53 mutations to provide additional predictive information. The study cohort included 713 consecutive immunotherapy patients with advanced lung adenocarcinomas of the Thoraxklinik Heidelberg who were negative for actionable EGFR and ALK/RET/ROS1 alterations. Two external cohorts of patients treated with immunotherapy (SU2C-ICI: n=247, MSK-ICI: n=135) and two external cohorts of surgical early stage patients were additionally analyzed (TCGA-LUAD: n=417, MSK-LUAD: n=394). Therapy benefit was assessed stratified by KRAS and TP53 mutations. RNA-Seq data of TCGA were analyzed to reveal the molecular characteristics of KRASmut/TP53mut tumors. Analyzing overall survival, an interaction between KRAS and TP53 mutations was observed in univariate and multivariate analyses (HR=0.56, p=0.0044 and HR=0.53, p=0.0021). KRASmut/TP53muts tumors performed better than tumors not harboring the dual mutation configuration (HR=0.71, CI 0.55-0.92). This observation could be confirmed in the external cohorts of immunotherapy patients (SU2C-ICI: HR=0.54, CI 0.28-1.03 and MSK-ICI: HR=0.35, CI 0.14-0.88), whereas KRASmut/TP53mut was not associated with prolonged survival in the surgical cohorts. Tumor mutational burden, proliferation (measured by TOP2A mRNA expression), and PD-L1 mRNA were significantly higher in TP53mut compared with TP53wt tumors, regardless of KRAS status. Genome-wide mRNA expression analysis revealed 64 genes including the chemokine CX3CL1 (fractalkine) as specific transcriptomic characteristic of KRASmut/TP53mut tumors. In summary, KRAS/TP53 co-mutation predicts ICI benefit in univariate and multivariate survival analyses and is associated with unique molecular tumor features. Further validation studies are warranted. Mutation testing of the two genes can be easily implemented using small gene panels or even single gene analyses. Citation Format: Jan Budczies, Eva Romanovsky, Martina Kirchner, Olaf Neumann, Miriam Blasi, Johannes Schnorbach, Rajiv Shah, Farastuk Bozorgmehr, Rajkumar Savai, Thorsten Stiewe, Solange Peters, Peter Schirmacher, Thomas Michael, Daniel Kazdal, Petros Christopoulos, Albrecht Stenzinger. KRAS and TP53 co-mutation predicts benefit of immune checkpoint blockade in lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2487.
Abstract 5524: Identification of PAEP as an immune activity modulator to mediate the immune resistance in tumor metastasis
Authors: Rand Gabriel M. Buenaventura, Weiping Chen, Shuling Zhang, Beverly Mock, Glenn Merlino, Yanlin Yu
Journal: Cancer Research (2024)

Abstract Most cancer-related deaths are associated with the complex phenotypic behavior of metastasis, a process in which tumor cells spread from their initial site to distant sites. To successfully metastasize, the tumor cell will be required to make numerous adjustments and survive a series of stages involving intravasation, circulation in the blood or lymph system, extravasation, and growth at distant organs, and overcome the challenges of immunosurveillance. The tumor microenvironment is the ecosystem that surrounds and feeds the tumor. The molecular mechanism by which the metastatic tumors survive and escape from immune attack in the tumor microenvironment remains unclear. To study the molecular mechanism of interaction between metastatic tumors and the immune system in metastasis, we established immune-resistant metastatic models. We identified that PAEP, a progestogen-associated endometrial protein, is significantly upregulated in immune-resistant metastatic tumors compared with non-immune-resistant tumors. PAEP is a glycoprotein that inhibits cell immune function and plays an essential role in the pregnancy process. To examine the function of PAEP in tumor metastasis, we first introduced PAEP into non-immune resistant and poorly metastatic melanoma and rhabdomyosarcoma (RMS) cells. We found that overexpression of PAEP significantly promotes tumor metastatic potential of both melanoma and RMS cells in immunocompetent mice. Interestingly, there was no difference in metastasis between the control and overexpression groups in immunodeficient mice. These data suggest that PAEP may mediate tumor metastasis relating to host immunity. To further confirm the function of PAEP in tumor metastasis, we use CRISPR/Cas9 technology to knockout endogenous PAEP and will test the metastatic potential in different hosts. We will also investigate the molecular mechanisms using RNA sequencing and Digital Spatial Profiling (DSP) to analyze the metastatic samples. Our study will uncover a new mechanism for how tumors survive in the microenvironment and identify a novel target for the treatment of metastatic diseases. Citation Format: Rand Gabriel M. Buenaventura, Weiping Chen, Shuling Zhang, Beverly Mock, Glenn Merlino, Yanlin Yu. Identification of PAEP as an immune activity modulator to mediate the immune resistance in tumor metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5524.