tbuckley/cabot-search huggingface dataset:
Abstract LB157: Discovery of HP537, a potent and selective p300/CBP inhibitor for the treatment of hematologic malignancies
Authors: Jing Li, Zhilin Tu, Jian Peng, Lei Fan, Hua Yu, Fei Wang, Xinghai Li
Journal: Cancer Research (2024)

Abstract E1A-binding protein P300 (p300) and its paralog CREB binding protein (CBP) are key acetyl transferases (HAT) and transcriptional co-factors. p300/CBP bromodomain (BRD) inhibition reduces acetylation of H3K27 at enhancers, leading to suppression of enhancer-driven gene expression, such as MYC and IRF4 that are critical for the initiation, progression, and chemoresistance of hematological malignancies. Thus, p300/CBP inhibition is a highly potential therapeutic strategy for the treatment of hematological malignancies, including multiple myeloma (MM), non-Hodgkin lymphoma (NHL) and leukemia. We have discovered HP537 that competitively inhibits an acetylated peptide substrate to bind BRD of p300/CBP with IC50 &amp;lt; 5 nM. HP537 does not inhibit the enzymatic activity of HAT domain of p300/CBP and HAT1, nor has binding affinity for other BRD containing proteins including BRD4 and BRD9. HP537 inhibits proliferation of a wide range of cell lines derived from MM, leukemia and lymphoma with IC50 values ranged from 0.01 μM to 0.4 μM. Protein expression levels of acetylated H3K27, c-Myc and IRF4 are significantly decreased by HP537 in MM, NHL and acute myelogenous leukemia (AML) cell lines in a dose- and time-dependent manner. HP537 robustly and dose-dependently inhibits tumor growth in OPM-2 (MM), MOLM-16 (AML), and KARPAS-422 (NHL) cell line derived tumor xenograft (CDX) mouse models. Down-regulation of c-Myc and IRF4 are also observed in the tumor samples. In conclusion, HP537 is a novel, potent and selective inhibitor of p300/CBP BRD. The pre-clinical data supports the clinical development of HP537 for the treatment of hematological malignancies. A FIH study of HP537 in cancer patients is planned to start in 2024. HP537 structure will not be disclosed. Citation Format: Jing Li, Zhilin Tu, Jian Peng, Lei Fan, Hua Yu, Fei Wang, Xinghai Li. Discovery of HP537, a potent and selective p300/CBP inhibitor for the treatment of hematologic malignancies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB157.
Abstract LB259: Cell context-dependent role of KDM5D in ATR and CHK1 inhibitor sensitivity in prostate cancer
Authors: Wenxiao Zheng, Yuzhou Chen, Qiming J. Wang
Journal: Cancer Research (2024)

Abstract Epigenetic regulation plays an important role in prostate cancer progression and metastasis. KDM5D is a male-specific histone-modifying enzyme encoded on the Y chromosome that demethylates di- and tri-methylated forms of lysine 4 in histone H3, resulting in transcriptional repression of certain genes. In this study, we investigated the role of KDM5D in resistance to inhibitors targeting the G2/M cell cycle checkpoint kinase CHK1. Loss of KDM5D expression was associated with reduced cell proliferation and resistance to the CHK1 inhibitor SRA737 in castration-resistant (CRPC) and neuroendocrine (NEPC) prostate cancer cell lines. In KDM5D expressing cells, depletion of KDM5D differentially impacted the proliferation of prostate cancer cell lines. The androgen-sensitive LNCaP cell line was particularly sensitive to the knockdown of KMD5D. On the other hand, in CRPC cell line 22Rv1, the knockdown of KDM5D caused resistance to both inhibitors, indicating a dual role of KDM5D in mediating ATR and CHK1 inhibitor sensitivity and cell proliferation in prostate cancer cells. Further analysis demonstrated a self-regulatory cycle between CHK1 and KDM5D in 22Rv1 cells, where depletion of KMD5D reduced CHK1 mRNA, while decreased CHK1 caused upregulation of KDM5D and overexpression of KDM5D resulted in increased CHK1 expression. The relevance of this regulatory mechanism to ATR and CHK1 inhibitor sensitivity is currently under investigation, along with several potential mediators of the differential responses to these inhibitors. Additional ATR and CHK1 inhibitors will also be examined in this context. This study may uncover novel biomarkers for ATR and CHK1 inhibitors that are currently in clinical trials for various cancers. KDM5D may be used to stratify prostate cancer patients receiving these highly potent anticancer agents. Citation Format: Wenxiao Zheng, Yuzhou Chen, Qiming J. Wang. Cell context-dependent role of KDM5D in ATR and CHK1 inhibitor sensitivity in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB259.
Abstract LB358: Program and epigenetic control of stemness and exhaustion of tumor infiltrating CD8+ T lymphocyte
Authors: Dorina Avram, Timothy Shaw, Shari Pilon-Thomas, Leonardo Silvane, Tomas Zelenka
Journal: Cancer Research (2024)

Abstract Tumor infiltrating CD8+ T lymphocytes (TILs) develop a state of exhaustion, become terminally exhausted (Ttex) and fail to control tumor growth through cytolytic activity. At an early stage, however, progenitors of exhausted (pTex) TILs are renewable and still reprogrammable, and can generate efficient cytolytic effector cells. pTex highly express stemness program genes. There is a high interest in understanding the mechanisms that control stemness and exhaustion programs of TILs. In the current study we investigated the consequences of the removal of the transcription factor (TF) BCL11B in TILs on the control of the stemness and exhaustion programs, their epigenetics landscape, and the impact on the pTex versus Ttex TIL status. Using scRNAseq, bulk RNAseq and epigenomics approaches, we positioned BCL11B upstream of essential TFs of the stemness and exhaustion programs, as well as of the cytolytic activity program. BCL11B-/- CD8+ TILs have increased stemness and elevated effector program, but reduced exhaustion, and they promoted a superior response compared to WT TILs, restricting tumor growth. Importantly, evaluation of BCL11B KO signature in patients with metastatic melanoma treated with check point inhibitors, show a more favorable response and survival in the patients with enriched BCL11B KO TIL signature. Thus these results indicate that BCL11B constitutes a promising target for therapeutic intervention in cancer cell therapies to sustain stemness, cytolytic activity and reduce exhaustion. Citation Format: Dorina Avram, Timothy Shaw, Shari Pilon-Thomas, Leonardo Silvane, Tomas Zelenka. Program and epigenetic control of stemness and exhaustion of tumor infiltrating CD8+ T lymphocyte [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB358.
Abstract CT155: Trial in progress: A phase Ia/Ib, an open-label, multicenter study of ZL-1310 to evaluate the safety, tolerability, and pharmacokinetics in subjects with small cell lung cancer
Authors: Afshin Dowlati, Alexander Spira, Xiaodong Shen, Yinjia Fu, Yiyuan Pan, Linda Liu, Renke Zhou, Yi-Long Wu
Journal: Cancer Research (2024)

Abstract Background: ZL-1310, a novel antibody-drug conjugate (ADC) targeting delta-like protein 3 (DLL3) with a camptothecin derivative as its payload via a protease-cleavable linker, employs TMALIN® (Tumor Microenvironment Activable LINker-payload) ADC technology platform. DLL3, an inhibitory Notch pathway ligand and a validated target for directed therapy, is highly expressed in more than 80% of patients with small cell lung cancer (SCLC) and also has variable expression in other neuroendocrine (NE) tumors. There remains an unmet medical need for 2nd-line SCLC, as the standard of care chemotherapy has a modest response rate of ~25%. ZL-1310 is designed to minimize payload toxicity and improve anti-tumor effectiveness. Methods: This is an open-label, multiple-dose, phase 1 study of ZL-1310 administered to subjects with relapsed/refractory (r/r) metastatic SCLC who have progressed after at least one platinum-based chemotherapy regimen. The study consists of two parts: Part 1 (dose escalation) and Part 2 (dose expansion). In Part 1, the Bayesian optimal interval (BOIN) design is employed for dose escalation, while in Part 2, patients will be randomized into two cohorts with different doses of ZL-1310 to further define safety and preliminary antitumor activity. The major inclusion criteria are as follows: (1) Subjects must have histologically or cytologically confirmed metastatic or extensive-stage SCLC with no more than 3 prior regimens in the r/r setting. (2) Subjects must have at least one measurable target lesion as defined by RECIST v1.1. (3) Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. The major exclusion criteria include: (1) Prior exposure to DLL3-targeted therapy. (2) Subjects with symptomatic or uncontrolled brain metastasis requiring concurrent treatment, impaired major organ functions, active autoimmune disease, or active infections.Part 1 Dose Escalation is recruiting subjects in the US and China. Citation Format: Afshin Dowlati, Alexander Spira, Xiaodong Shen, Yinjia Fu, Yiyuan Pan, Linda Liu, Renke Zhou, Yi-Long Wu. Trial in progress: A phase Ia/Ib, an open-label, multicenter study of ZL-1310 to evaluate the safety, tolerability, and pharmacokinetics in subjects with small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT155.
Abstract LB115: Strong antitumor effect elicited by inhibition of AKT or FOXP3 in combination with anti-PD-L1 in Pten mutant lung squamous cell carcinoma
Authors: Maeva Houry, Miriam Redrado, Larissa Carnevalli, Simon Barry, Nuria Galan, Nerea Otegui, Sergio Leon, Luis Montuenga, Francisco Exposito, Alfonso Calvo
Journal: Cancer Research (2024)

Abstract PTEN is mutated in ~10% lung squamous cell carcinoma (LUSC) patients, which results in hyperactivation of PI3K-AKT-mTOR signaling pathways. Mutations in the PI3K-AKT-mTOR pathway influence the configuration the tumor microenvironment (TME). We have recently reported that PTEN mutations in LUSC are associated with increased tumor infiltration of T regulatory immunosuppressive cells (Tregs) and fibrogenesis (PMID: 37311042). Moreover, we have demonstrated that PTEN mutations in LUSC induces resistance to anti-PD-1 therapy. Based on these findings, we have investigated whether blockade of AKT signaling with capivasertib (AZD5363) and/or inhibition of Treg-associated FOXP3 transcription factor, using the FOXP3 targeting antisense oligonucleotide (ASO) AZD8701 (FOXP3i), would cause tumor growth inhibition in the PTEN mutant context. In in vitro assays we found that Pten-null LUSC UN680 murine cells were highly sensitive to capivasertib, with inhibition of the AKT-mediated signaling cascade, reduction in cyclin D1 levels, cytoplasmic translocation of FOXO1 and increase in apoptosis and autophagy. In in vivo studies using Pten-null UN680 cells subcutaneously injected in AJ immunocompetent mice, treatment with either capivasertib or the FOXP3i induced &amp;gt;90% tumor regression and increased survival. Moreover, on average 3/8 (~37%) animals were cured in each treatment group. In a re-challenge experiment performed in animals cured by the FOXP3i, tumors were not developed upon injection of Pten-null UN680 cells, demonstrating immunological memory. Combination of capivasertib+FOXP3i at the same doses did not cause further tumor growth inhibition, but combination of capivasertib+anti-PD-L1 or FOXP3i+anti-PD-L1 increased antitumor benefit compared to monotherapy treatment, and further increased survival. In summary, we demonstrate that immunotherapy resistant tumors with hyperactivation of AKT due to Pten mutation are highly sensitive to AKT or FOXP3 inhibition and that combinatorial strategies using these targets and anti-PD-L1 can be appropriate strategies to treat these tumors. Citation Format: Maeva Houry, Miriam Redrado, Larissa Carnevalli, Simon Barry, Nuria Galan, Nerea Otegui, Sergio Leon, Luis Montuenga, Francisco Exposito, Alfonso Calvo. Strong antitumor effect elicited by inhibition of AKT or FOXP3 in combination with anti-PD-L1 in Pten mutant lung squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB115.
Abstract LB199: Condensate modulator sequesters beta-catenin into depot condensates and demonstrates competitive anti-tumor activity in animal models ofcolorectal cancer
Authors: Costa Salojin, Douglas Baumann, Adam Talbot, Kip West, Thomas Durand-Reville, Isaac Klein, Ann Boija
Journal: Cancer Research (2024)

Abstract Constitutive activation of beta-catenin is a well-known driver of malignancy. However, traditional drug discovery approaches have proven challenging and largely unsuccessful in identifying therapeutic agents to modulate the function of beta-catenin. Biomolecular condensates have recently been demonstrated to play key roles in regulating most cellular processes and biological pathways by compartmentalizing biomolecules in membranelles organelles, thus lending novel opportunities to drug previously “undruggable” targets. Here, we leverage condensate biology to discover small molecules that reverse the hyperactive function of beta-catenin in colorectal cancer by entrapping it into depot condensates. We developed a high-throughput phenotypic assay that identifies beta-catenin condensate-modifying compounds (c-mods). Through condensate screening and functional secondary assays, we have identified c-mods that sequester beta-catenin into depots, induce selective cancer cell killing, and reverse oncogenic beta-catenin specific gene expression programs. C-mods identified in our screen are effective in genetically diverse colorectal cancers and a range of Wnt-associated cancers, providing the opportunity to treat a broad patient population. Furthermore, oral dosing of lead c-mod demonstrates competitive tumor growth inhibition as a single agent in xenograft and PDX models of colorectal cancer. Taken together, these results highlight the promise of condensate biology in drugging previously intractable high-value targets in oncology and developing novel treatments for patients suffering from diseases of high unmet need. Citation Format: Costa Salojin, Douglas Baumann, Adam Talbot, Kip West, Thomas Durand-Reville, Isaac Klein, Ann Boija. Condensate modulator sequesters beta-catenin into depot condensates and demonstrates competitive anti-tumor activity in animal models ofcolorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB199.
Abstract LB099: Identifying actionable genomic alterations in non-small cell lung cancer through the analysis of extracellular vesicles in plasma
Authors: Hongzhang He, Jadranka Milosevic, Siyang Zheng
Journal: Cancer Research (2024)

Abstract Lung cancer is the second most common cancer worldwide, accounting for 2.2 million new cases and 1.8 million deaths in 2020. Personalized targeted therapy based on actionable molecular markers has completely transformed the therapeutic landscape in NSCLC, which has improved considerably the overall survival. However, ~50% of NSCLC patients with tissue biopsy inaccessible or inadequate, limiting biomarker testing and access to targeted therapies. The availability of a wide range of highly effective targeted therapy options for NSCLC justifies the significance of developing non-invasive and cost-effective detection assays for guiding targeted therapy selection in NSCLC.Extracellular vesicles (EVs) are lipid-bilayer-enclosed vesicles of sub-micrometer size that are secreted by virtually all cell types. They contain hundreds of different proteins, thousands of intact RNA species, and double-stranded DNA (dsDNA) fragments that sample the entire human genome. Recent findings further corroborate the potential role of EVs in early cancer screening, cancer diagnosis, treatment selection and monitoring. In this study, we used lipid nanoprobe (LNP) for EV isolation from plasma and droplet digital PCR assay for detecting actionable genomic alternation to aid targeted therapy selection in NSCLC. Specifically, we extracted EV associated DNA/RNA from plasma first, and then we used the individual ddPCR assays for detecting KRAS mutations, EGFR mutations, and ALK fusions from isolated EVs associated nucleic acids, respectively. We identified KRAS mutations G12C/G12S/G13C/G12A/Q61H, EGFR L858R mutation and exon 19 deletion, and ALK-EML4 gene fusion variant 3 from 12 NSCLC patients that matched the mutation status obtained from patient tissue specimens. Only in 1 out 13 patients, EV mutation status did not match the mutation status from the tissue specimen. This data indicated that clinical actionable gene mutations are present in EVs associated nucleic acids isolated from plasma samples of NSCLC patients. We anticipate that this novel non-invasive EVs-based actionable genomic alterations detection test would efficiently assist physicians/oncologists in selecting optimal targeted therapies for cancer treatment, as recommended by National Comprehensive Cancer Network (NCCN) guidelines for NSCLC. Citation Format: Hongzhang He, Jadranka Milosevic, Siyang Zheng. Identifying actionable genomic alterations in non-small cell lung cancer through the analysis of extracellular vesicles in plasma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB099.
Abstract LB330: CWH43 as a prognostic marker and therapeutic target in colorectal cancer
Authors: Cheng-Chin Lee, Yu-Jia Chang, Chien-Yu Huang
Journal: Cancer Research (2024)

Abstract Colorectal cancer (CRC) remains a significant global health issue, particularly challenging due to the poor prognosis of its metastatic form. This highlights the critical need for novel and effective therapeutic targets to manage disease progression. A key focus of our research is the Cell Wall Biogenesis 43 C-Terminal Homolog (CWH43), which plays an essential role in GPI anchor biosynthesis and lipid remodeling, crucial for attaching membrane proteins to cell membranes. Our study aimed to clarify the function of CWH43 in CRC progression and evaluate its potential as a therapeutic target. Through an integrated bioinformatics analysis using public cancer databases, coupled with experimental validations in CRC cell models, we noted a conspicuous decrease in CWH43 mRNA levels in CRC tissues compared to normal tissue. This decrease in CWH43 expression correlated with poorer prognoses in CRC patients. In our experimental findings, we discovered that suppressing CWH43 led to increased proliferation, migration, and invasiveness of CRC cells, whereas its overexpression inhibited these processes. Notably, we observed elevated levels of CWH43 in CRC patients who showed a lower response to chemotherapy. Particularly in advanced-stage CRC patients (T4 and N2), high CWH43 expression correlated with reduced overall survival and shorter progression-free intervals, suggesting a potential association with chemotherapy resistance. In our cellular experiments, overexpression of CWH43 in CRC cells resulted in decreased sensitivity to chemotherapy drugs like CPT11, 5-FU, and oxaliplatin, which was consistent with a reduction in the expression of apoptosis-related markers. Additionally, there was a notable negative correlation between CWH43 expression and radiation sensitivity. Our Gene Set Enrichment Analysis (GSEA) revealed a significant connection between CWH43 and pathways involved in oxidative phosphorylation and fatty acid metabolism, indicating its role in regulating ferroptosis. We also demonstrated that overexpressing CWH43 in CRC cells increases the levels of multiple ferroptosis suppressors. Importantly, the use of ferroptosis inducers appeared to counteract the chemotherapy resistance influenced by CWH43. Based on these findings, we propose that CWH43 plays a role in inhibiting ferroptosis, contributing to therapeutic resistance in CRC. Therefore, targeting CWH43 could be a promising strategy for developing ferroptosis-inducing therapies, offering a new avenue for the treatment of CRC, especially in cases resistant to traditional therapies. Citation Format: Cheng-Chin Lee, Yu-Jia Chang, Chien-Yu Huang. CWH43 as a prognostic marker and therapeutic target in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB330.
Abstract LB048: Unleashing the power of p53 mRNA therapeutics to suppress proliferation of p53 mutant tumors
Authors: Yong Ho Heo, Seung-Hyun Shin, Youngjin Han, Chang Gyu Lim, Innah Kim, Ji Hee Lee, Gunwoo Lee, Seongju Jeong, Yunjae Kim, Jooyun Byun, Daejin Kim, In Young Choi
Journal: Cancer Research (2024)

Abstract The p53 protein, recognized as the guardian of the genome, plays a pivotal role in suppressing tumor formation. The TP53 gene, which encodes the p53 protein, is commonly subject to mutations and deletions in many cancer types resulting in loss of tumor suppressor activity. A significant proportion of patients diagnosed with lung, pancreatic, ovarian, and head and neck cancers exhibit the expression of mutant p53 in their tumors, correlating with unfavorable prognosis and survival outcomes.This study endeavors to assess the efficacy of therapeutic tumor suppressive mRNA which induces expression of wild-type p53 protein across diverse cancer types. Optimization of the 5’ and 3’ untranslated regions (UTRs) and the 5’ cap has been undertaken to enhance the efficient expression of p53 mRNA. The growth inhibitory potential of p53 mRNA therapy has been evaluated across p53 mutant cancer cell lines representing various cancer origins, along with normal or p53 wild-type cancer cell lines. We have substantiated that the p53 mRNA therapeutics can selectively inhibit the proliferation of p53 mutant cancer cells. Furthermore, we have confirmed that p53 mRNA treatment upregulated modulator of apoptosis (PUMA) and B-cell translocation gene 2 (BTG2) and cell cycle arrest via p21 upregulation. In vivo efficacy assessments of the lipid nanoparticle (LNP)-encapsulated p53 mRNA have been conducted in lung, pancreatic, and ovarian cancer xenograft models. Both regional intratumoral (i.t) and systemic intravenous (i.v) administrations of the p53 mRNA therapeutics have shown substantial suppression of tumor growth, leading to prolonged mouse survival. These results underscore the potential of the p53 mRNA therapeutics as a promising avenue for targeted cancer treatment, offering insights into the selective inhibition of p53 mutant cancer cells. Citation Format: Yong Ho Heo, Seung-Hyun Shin, Youngjin Han, Chang Gyu Lim, Innah Kim, Ji Hee Lee, Gunwoo Lee, Seongju Jeong, Yunjae Kim, Jooyun Byun, Daejin Kim, In Young Choi. Unleashing the power of p53 mRNA therapeutics to suppress proliferation of p53 mutant tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB048.