bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 6049: Cell-based PROTAC screening for cancer drug discovery
Authors: Wan Yong , Ma Haiqing , Wu Jianghong
Published: March 2024

Proteolysis-Targeting Chimeras (PROTACs) have emerged as a promising strategy for selectively degrading specific target proteins, thereby offering a novel approach to precision cancer therapy. Among the most notable oncogenes, KRAS with the G12C mutation is responsible for 45%-50% of KRAS mutations in non-small cell lung carcinomas. Additionally, BRD4, a well-studied member of the Bromo- and Extra-Terminal (BET) protein family, is implicated in various hematological and solid tumors. The implementation of cell-based screening for PROTACs targeting either KRAS(G12C) or BRD4 represents a highly valuable platform for advancing cancer drug discovery. We utilized the NanoBRETTM Ternary Complex Assay, NanoBiTTM Assay, and Western Blot assay to evaluate the efficacy of PROTACs. The NanoBRETTM Ternary Complex Assay revealed that KRAS G12C degrader-1 and LC-2 effectively degrade KRAS(G12C), while dBET6 and MZ-1 demonstrated the ability to degrade BRD4. Notably, the NanoBiTTM assay showed that LC-2 dose-dependently degrades KRAS(G12C) in HEK293 cells co-transfected with KRAS(G12C)-LgBiT and KRAS(G12C)-SmBiT. Moreover, BET6 exhibited a dose-dependent degradation of endogenous BRD4 in HepG2 cells, and LC-2 demonstrated the degradation of endogenous KRAS(G12C) in MiaPaCa2 cells. In summary, the development of a robust cell-based assay platform for high-throughput screening of PROTACs marks a substantial advancement in cancer drug discovery. This approach not only enables the identification of promising PROTACs but also holds the potential for more effective and targeted interventions in the ongoing battle against cancer.

Citation Format: Yong Wan, Haiqing Ma, Jianghong Wu. Cell-based PROTAC screening for cancer drug discovery [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 6049.
Abstract 6050: Targeting KRAS G12D mutant tumors with the PROTAC degrader RP03707
Authors: Ji Xiang , Li Huanping , Wu Gang , Zhang Qiguo , He Xiaolin , Wu Yanpeng , Zong Bing , Xu Xiaojin , Liang Chao , Wang Beibei , Zhang Yuwei , Hu Qingyao , Zhou Jiaxin , Guo Weihui , Bai Bing , Wang Lin , Ai Jinchao , Zhang Leduo , Zhou Honggui , Sun Shihao , Wang Yijie , Wang Youhong , Fan Qiming , Chen Dawei , Zhou Tianlun , Lu Jiasheng
Published: March 2024

RAS oncogene mutations are prevalent in approximately 19% of cancer patients, with the most frequent alteration occurring in codon 12 of the KRAS gene, resulting in a variety of G12X oncoproteins. Recent advances in drug discovery have yielded several KRAS G12C inhibitors currently in clinical use, benefiting a subset of patients. However, addressing the high-prevalence G12D mutation remains a substantial unmet medical need. Targeted protein degradation using PROTAC molecules offers a promising approach for treating KRAS G12D-associated tumors, potentially providing superior efficacy and mitigating the development of resistance, a challenge frequently observed with KRAS G12C inhibitors in clinical settings. In the present study, we report a PROTAC compound RP03707 that efficiently induces the degradation of the KRAS G12D mutant protein and inhibits tumor growth. Treatment of AsPc-1 cells with RP03707 results in significant degradation of the KRAS G12D protein, with a DC50 value in the sub-nanomolar range. Within 24 hours, the compound eliminates over 90% of G12D proteins and effectively suppresses downstream cellular MAPK signaling. Additional in vitro experiments demonstrate that RP03707 inhibits cell proliferation in multiple KRAS G12D mutant cell lines, surpassing the anti-tumor efficacy of enzyme inhibitors. In a mouse GP2d xenograft tumor model, a single intravenous administration of RP03707 at 10 mpk results in excellent compound penetration and retention in tumor tissues, followed by 90% reduction of G12D protein levels for 7 days. Profound inhibition of tumor growth is observed not only in mouse GP2d xenograft but also in other mouse KRAS G12D tumor models, even when the compound is administered in low and infrequent doses. Moreover, RP03707 exhibits high selectivity for degrading the KRAS G12D protein and possesses favorable drug-like properties. RP03707, therefore, meets the criteria for advancing into drug development and represents a valuable therapeutic option for treating KRAS G12D-associated tumors.

Citation Format: Xiang Ji, Huanping Li, Gang Wu, Qiguo Zhang, Xiaolin He, Yanpeng Wu, Bing Zong, Xiaojin Xu, Chao Liang, Beibei Wang, Yuwei Zhang, Qingyao Hu, Jiaxin Zhou, Weihui Guo, Bing Bai, Lin Wang, Jinchao Ai, Leduo Zhang, Honggui Zhou, Shihao Sun, Yijie Wang, Youhong Wang, Qiming Fan, Dawei Chen, Tianlun Zhou, Jiasheng Lu. Targeting KRAS G12D mutant tumors with the PROTAC degrader RP03707 [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 6050.
Abstract 6124: A comprehensive pan-cancer study nominating NF-κB-mediated TNFA signaling-induced hypoxia as a risk factor in Hispanic cancer progression
Authors: Samanta Tagari , Park Jun Hyoung , Kaipparettu Benny Abraham
Published: March 2024

The Hispanic (HA) population is the second largest racial/ethnic group in the United States after non-Hispanic White (NHW). Though the HA population usually has a lower reported incidence of cancers compared to NHW, there are racial disparities exist in the mortality rate of some of the cancers. Factors related to the Social Determinants of Health (SDOH), such as higher poverty rates, less education, and reduced access to health care, are known to increase the risk of diagnosing advanced-stage cancer in HA compared to the NHW population. The contribution of such SDOH in the HA cancer population has been studied in the past years. However, the contribution of biological and genetic mechanisms to HA cancer disparity has not been well understood. Thus, in this study, we performed a comprehensive analysis of different databanks to understand the common genetic and biological factors that contribute to the pan-cancer disparity in the HA population. To identify HA and NHW populations, we used self-reported racial/ethnic information. Analysis of the “All of Us” database suggested a high prevalence of infection-related cancers such as Liver, Stomach, and Cervix Uteri in the HA population compared to the NHW population. SEER database also showed an increased percentage of diagnoses with infection-related cancers and poor survival of the HA population with these cancers compared to the NHW. We then analyzed the TCGA transcriptome data from primary tumors from HA and NHW patients. We only selected cancers with data from at least ten patients in each group. TCGA data confirmed that the tumors from HA cancer patients primarily express high inflammatory and immune-responsive signatures. Specifically, we found a high enrichment of NF-κB induced TNFA signaling in HA tumors. We also observed a significant correlation between TNFA and Hypoxia signature in many HA cancers. Since hypoxia is known to be associated with resistance to radiation and chemotherapy, targeting the increased hypoxia signature in HA tumors may be critical for sensitizing HA patients to cancer therapy. Overall, our pan-cancer analyses suggest an increased prevalence of many infection-related cancers in the HA population. HA tumors are enriched with TNFA, NF-κB, and hypoxic signatures. Specific targeting of these signatures may be critical in managing the HA patients who currently suffer from racial disparity in cancer incidence and survival.

Citation Format: Tagari Samanta, Jun Hyoung Park, Benny Abraham Kaipparettu. A comprehensive pan-cancer study nominating NF-κB-mediated TNFA signaling-induced hypoxia as a risk factor in Hispanic cancer progression [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 6124.
Abstract 6175: Deep learning-based survival prediction for hepatocellular carcinoma using whole slide images
Authors: Lee Sung Hak , Jang Hyun-Jong
Published: March 2024

There is an increasing need for classifiers to effectively stratify prognosis in patients with hepatocellular carcinoma (HCC). Deriving interpretable prognostic features using deep-learning (DL)-based prognostic models from pathology images remains a challenge. In this study, we developed a computational approach based on DL to predict the overall survival (OS) of HCC patients from formalin-fixed paraffin-embedded histopathology whole slide images. A DL model for classifying good and poor prognosis was developed on a total of 460 patients with 2 independent cohorts from Seoul St. Mary's Hospital. The primary outcome was OS. The training set (SSM1, n = 292) included HCC patients that had undergone surgical resection. The classifier was then independently tested on the second HCC dataset (SSM2, n = 168). The area under the curve (AUC) for the receiver operating characteristic (ROC) curves was 0.850 and 0.781 for SSM1 and SSM2 datasets, respectively. In addition, we have tried to establish DL model for prediction of OS based on clinicopathological features, including Edmondson-Steiner grade, pT stage, vascular invasion, Ki-67 index, and cytokeratin 19 immunohistochemical expression. Random forest model was applied to classify the good and poor prognosis groups and The AUROCs for the random forest was 0.705 for the SSM1 dataset, which are inferior to that of DL prediction. These findings suggest that the DL techniques can be applied to refine the prognostic prediction of HCC patients.

Citation Format: Sung Hak Lee, Hyun-Jong Jang. Deep learning-based survival prediction for hepatocellular carcinoma using whole slide images [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 6175.
Abstract 6227: A systems biology approach for identifying targetable vulnerabilities in Ewing sarcoma
Authors: Dela Cruz Filemon S. , Mundi Prabhjot S. , Siddiquee Armaan , Guillan Kristina , You Daoqi , Sanchez Glorymar Ibanez , Ndengu Andoyo , Califano Andrea , Kung Andrew L.
Published: March 2024

Background: Targeting fusion oncoproteins like the canonical EWS/ETS fusions in Ewing sarcoma remain an elusive challenge. To circumvent these challenges, we have utilized transcriptome-based systems biology approaches that identify targetable Master Regulator proteins (MRs) critical to maintaining the cancer cell state. OncoTarget analysis generates a rank order list of targetable MRs while OncoTreat analysis uses cognate cell lines matched to patient tumors to identify drugs that invert the MR signature. We used OncoTarget and OncoTreat analyses to identify existing drugs which could be repurposed to target MRs active in Ewing sarcoma.

Methods: A gene regulatory interactome was developed from 122 pediatric sarcoma samples to enable identification of MR targets using OncoTarget. To enable OncoTreat analysis, 2 cognate cell lines were subjected to high-throughput drug perturbational screens. Cells were treated with sub-lethal concentrations of 335 compounds (FDA approved or investigational drugs). Ex vivo drug screens using PDX-derived cells were performed as a complementary assay to validate predictions. In vivo validation was performed in Ewing sarcoma PDXs.

Results: The MR architecture of 3 Ewing sarcoma PDX models was evaluated using OncoTarget. OncoTreat analysis identified 43 drugs predicted to be active in at least 1 Ewing sarcoma PDX while OncoTarget analysis identified 20 MR targets predicted in at least 1 Ewing sarcoma PDX. DOT1L and AURKB were predicted targets across multiple Ewing sarcoma PDXs. Ex vivo screening of dissociated cells from 2 Ewing sarcoma PDXs was performed to select the most potent agents for in vivo validation. Three OncoTreat (clarithromycin, tivozanib and obataclax) and two OncoTarget (DOT1L targeted with EPZ-5676 and AURKB targeted with baracertib) predicted drugs were evaluated in a STAG2 mutant Ewing sarcoma PDX and all demonstrated significant abrogation of tumor growth including complete regression in baracertib-treated animals (p<0.01).

Conclusion: These systems biology approaches can identify non-oncogene encoded vulnerabilities in Ewing sarcoma and hold the potential for expanding the number of therapeutic options for tumors driven by untargetable oncoproteins.

Citation Format: Filemon S. Dela Cruz, Prabhjot S. Mundi, Armaan Siddiquee, Kristina Guillan, Daoqi You, Glorymar Ibanez Sanchez, Andoyo Ndengu, Andrea Califano, Andrew L. Kung. A systems biology approach for identifying targetable vulnerabilities in Ewing sarcoma [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 6227.
Abstract 6265: FLCN variants and their role in parathyroid cancer and atypical parathyroid tumors
Authors: Burke Callie , Bellizzi Justin , Costa-Guda Jessica , Arnold Andrew
Published: March 2024

Parathyroid carcinoma (PC) is rare, poses challenges in definitive diagnosis and treatment, and carries a high rate of recurrence and mortality. Atypical parathyroid tumors (APT) have histopathologic features of malignancy but lack unequivocal evidence of invasion and are of uncertain malignant potential. Analysis of genetic alterations that may play a role in PC development, particularly those that might serve as markers of malignant potential, is important for further understanding this disease. FLCN is a gene found on chromosome 17 that encodes folliculin, a ubiquitously expressed protein with roles in multiple cellular processes such as apoptosis and cell signaling. Inactivating FLCN mutations cause Birt-Hogg-Dubé syndrome (BHD), an autosomal dominant condition characterized by benign fibrofolliculomas, pulmonary cysts and spontaneous pneumothorax, and increased risk of renal cancer. Benign parathyroid tumors had previously been reported in a few BHD patients and recently one study has reported a link between FLCN mutations and parathyroid carcinoma. Germline frameshift mutations in FLCN, accompanied by somatic loss of the normal allele, were reported in two unrelated PC patients, both with clinical features suggestive of BHD, but no established diagnosis of BHD. An identical somatic frameshift FLCN mutation was reported in one PC and one APT. Interestingly, the authors noted low coverage of FLCN on whole exome sequencing, resulting in the failure to detect variants identified by Sanger sequencing, thus raising the possibility that prior studies may have missed FLCN variants. To better understand the frequency of germline or somatic FLCN mutations in PC and APT, we performed Sanger sequence analysis of the entire coding region of the FLCN gene on available tumor DNA from 11 PCs and 15 APTs. We identified no inactivating FLCN mutations in any of the PC or APT samples examined. A germline missense variant, resulting in a p.Gly325Val change, predicted to be benign/tolerated by in silico analyses, was seen in one PC and a synonymous variant (c.1233G>A) was seen in one APT. The absence of pathogenic mutations in our series parathyroid carcinoma and atypical parathyroid tumors suggests that FLCN mutations are rare in these parathyroid tumors. Nevertheless, germline FLCN testing and/or additional screening for BHD-related lesions in parathyroid carcinoma patients merits further consideration and study.

Citation Format: Callie Burke, Justin Bellizzi, Jessica Costa-Guda, Andrew Arnold. FLCN variants and their role in parathyroid cancer and atypical parathyroid tumors [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 6265.
Abstract 627: IL-6 signaling via JAK/STAT axis influences PIM1 expression in renal cell carcinoma
Authors: Meza Kimberly S. , Seymour Kimberly , Holder Sheldon L.
Published: March 2024

Renal cell carcinoma (RCC) is a top ten malignancy in the U.S. Overexpression of the proviral integration site for moloney murine leukemia virus 1 (PIM1) kinase is associated with poor clinical outcomes in RCC patients. PIM1 is a constitutively active serine/threonine kinase promoting cell proliferation, apoptosis resistance, invasion, and migration. The mechanisms underlying PIM1 expression and its function in RCC are not fully delineated. IL-6 is a pleiotropic cytokine that activates the JAK/STAT signaling cascade. High serum IL-6 levels are associated with the poor prognosis of RCC patients and may contribute to RCC invasion and metastasis. STAT3/5 binds directly to the PIM1 promoter inducing PIM1 expression. An IL-6/STAT3/PIM1 axis exists in pancreatic and breast cancer. We previously reported that PIM1 is overexpressed in a panel of human RCC cell lines relative to normal and immortalized renal proximal tubule epithelial cells. We also identified that RCC cells secrete IL-6. Our prior studies suggest that differential expression of PIM1 may be linked to autocrine IL-6 signaling. We thus hypothesize that an IL-6/JAK/STAT pathway regulates the expression of PIM1 in RCC. To understand how IL-6 signaling through the JAK/STAT pathway may regulate PIM1 expression in RCC cells, we examined whether IL-6 blockade using anti-IL-6 antibody or tocilizumab, would modulate PIM1 expression. Similarly, we assessed whether ruxolitinib, and LLL12, a STAT3 inhibitor could regulate PIM1 expression. We then evaluated the effect of ruxolitinib treatment on cell viability. In RCC cell lines, IL-6 blockade through either anti-IL-6 antibody or tocilizumab was sufficient to decrease PIM1 protein levels. Treatment with ruxolitinib leads to a dose and time-dependent decrease in PIM1 levels. Incubation with a STAT3 inhibitor also resulted in decreased PIM1 levels in RCC cells. Treatment with ruxolitinib also appears to decrease cell viability in a dose-dependent manner. These results suggest that differential expression of PIM1 in RCC may be linked to autocrine IL-6 signaling via a JAK/STAT/PIM1 axis. Multiple FDA-approved agents are available that target this pathway. Further investigation is required to determine the efficacy of these agents in pre-clinical models and even clinical trials.

Citation Format: Kimberly S. Meza, Kimberly Seymour, Sheldon L. Holder. IL-6 signaling via JAK/STAT axis influences PIM1 expression in renal cell carcinoma [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 627.
Abstract 6277: Tall cell variant papillary thyroid carcinoma from Middle Eastern patients have worse outcome than classical papillary thyroid carcinoma using propensity score matching
Authors: Al-Kuraya Khawla S. , Parvathareddy Sandeep K. , Siraj Abdul K. , Ahmed Saeeda O. , Siraj Nabil , Manakhan Manal , Aldossari Hassan
Published: March 2024

The tall cell variant of Papillary Thyroid Carcinoma (TCV-PTC) is the most common aggressive variant of PTC. The impact of TCV-PTC on patients’ prognosis still remains controversial. Moreover, the clinico-pathological and prognostic effect of TCV-PTC from Middle Eastern ethnicity remains unexplored. We aimed to study TCV-PTC in comparison to classical PTC in Middle Eastern patients and their impact on prognosis. We performed a retrospective cohort study of tall cell variant (TCV-PTC) and classic variant of papillary thyroid carcinoma (CV-PTC) after post-surgical radioactive iodine therapy. We used the propensity score matching (1:3 matching ratio) to account for differences between recipients of TCV-PTC vs CV-PTC. Univariate and multivariate analysis were performed to assess the independent factors for persistent/recurrent disease. Kaplan-Meier curve analyses were used to compare disease-free survival (DFS). In total, 174 (16.3%) patients with TCV-PTC and 891 (83.7%) patients with CV-PTC were included. After propensity score matching, 174 pairs of patients were selected (TCV-PTC, n = 174; CV-PTC, n = 522). In the matched analysis, higher proportions of TCV-PTC experienced persistent/recurrent disease compared with CV-PTC (25.7% vs 31.4%; p = 0.0119). In multivariate analyses of clinical and tumor characteristics, histological type of TCV-PTC (odds ratio, 2.09; 95% confidence interval, 1.28-3.40; p = 0.0031) was associated with increased risk of persistent/recurrent disease. The five-year DFS rates for the TCV-PTC and CV-PTC groups were 48.5% and 73.1%, respectively. The Kaplan- Meier analysis indicated that the TCV-PTC group (p < 0.0001) had shorter DFS. In conclusion, when other clinico-pathological factors were similar, this propensity score matched analysis showed that histological subtype TCV-PTC is by itself an independent predictive marker of persistent/recurrent disease in Middle Eastern patients. Therefore, individualized therapeutic approaches might be needed for this aggressive PTC subtype.

Citation Format: Khawla S. Al-Kuraya, Sandeep K. Parvathareddy, Abdul K. Siraj, Saeeda O. Ahmed, Nabil Siraj, Manal Manakhan, Hassan Aldossari. Tall cell variant papillary thyroid carcinoma from Middle Eastern patients have worse outcome than classical papillary thyroid carcinoma using propensity score matching [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 6277.
Abstract 6283: Tumor repressive effects of estrogen receptor β mRNA-based therapy in aggressive breast cancers
Authors: Cap Kim Cuong , Phillips Aireana , Pinto Karem A. Court , Zambo Kristina D. , Qian Wei , Zhou Jianying , Chang Jenny , Godin Biana , Thomas Christoforos
Published: March 2024

Inflammatory breast cancer (IBC) and triple-negative breast cancer (TNBC) are the most aggressive forms of breast cancer due to their high propensity to develop distant metastases and the lack of specific effective targeted therapies. The failure of previous research to produce viable therapeutic targets combined with the absence of estrogen receptor α (ERα) in TNBC and the majority of IBC led us to explore the second ER (ERβ) as a molecule with targeting potential. We previously reported the anti-metastatic effects of ERβ in both TNBC and IBC. Considering the anti-tumor activity together with the decreased expression of ERβ in IBC and TNBC tumors, we employed an mRNA-based approach to induce tumor-specific upregulation of the receptor and restore its anti-metastatic activity. Our findings show that complexes of ERβ mRNA with lipid nanoparticles (LNPs) enable in vitro translation of a functional protein with strong anti-invasive activity. More importantly, direct administration of ERβ mRNA-LNPs in orthotopically grown IBC and TNBC tumors results in high tumor levels of the receptor and an evident inhibition of metastasis demonstrating for the first time the ability of ERβ mRNA to prevent progression of the disease. Our study may have important clinical implications by establishing ERβ mRNA as a novel and specific therapy intervention that either alone or in combination with existing treatments can substantially repress metastasis, eliminate associated mortality and benefit patients with aggressive breast cancer.

Citation Format: Kim Cuong Cap, Aireana Phillips, Karem A. Court Pinto, Kristina D. Zambo, Wei Qian, Jianying Zhou, Jenny Chang, Biana Godin, Christoforos Thomas. Tumor repressive effects of estrogen receptor β mRNA-based therapy in aggressive breast cancers [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 6283.
Abstract 6314: Potent inhibition of tumor relapse after anti-HER2 affibody tagged with cotinine (switch) plus anti-cotinine switchable CAR T cell therapy by repeated re-injection of the switch
Authors: Kim Ki Hyun , Kim Soohwan , Lee Eun-Hoe , Lim Soo-Yoon , Kim Sung Min , Kim E-Young , Lee Hyun-Jong , Kim Seong Yeol , Yoon Min , Lee Young-Ha , Hwang In-Sik , Lee Yoon , Kim Jong-Hoon , Lee Jong-Seo , Chung Junho
Published: March 2024

Chimeric antigen receptor (CAR) T cells targeting CD19 or the B cell maturation antigen (BCMA) have demonstrated impressive initial clinical responses. However, on follow-up assessment, a notable fraction of the patients with significant initial clinical response eventually experienced relapse. CAR T cell therapies targeting solid tumors have shown an even lower rate of clinical response as well as shorter remission periods. A prior study has shown that re-injection of the anti-HER2 CAR T cells was effective in a rhabdomyosarcoma relapse patient (Cancer Res 79, LB147 (2019)), but the repeated production of CAR T cells is costly, thus raising questions about its feasibility in practice. Previously, we developed a cotinine-based CAR T cell system (zCART) comprised of a tumor antigen-specific affibody conjugated with cotinine and an anti-cotinine scFv CAR, and demonstrated the anti-tumor activity of an anti-HER2 zCART treatment in both in vitro and in vivo settings. In this study, we tested the efficacy of anti-HER2 zCART treatment in vivo using an intraperitoneal (IP) tumor model with a single infusion of zCART cells. The anti-HER2 switch was injected daily for 7 days. When the HER2 positive tumor relapsed, the mice were re-treated with the same dose of anti-HER2 switch treatment for an additional 7 days. We observed that re-injection of only the anti-HER2 switch and not combined with zCART cells effectively and potently inhibited relapse of HER2 positive tumors. Furthermore, the efficacy of the anti-HER2 switch re-injection treatment was maintained in one additional relapse. In summary, the zCART system has potential to treat cancer relapse following CAR T cell therapy without the need for an additional production round of CAR T cells.

Citation Format: Ki Hyun Kim, Soohwan Kim, Eun-Hoe Lee, Soo-Yoon Lim, Sung Min Kim, E-Young Kim, Hyun-Jong Lee, Seong Yeol Kim, Min Yoon, Young-Ha Lee, In-Sik Hwang, Yoon Lee, Jong-Hoon Kim, Jong-Seo Lee, Junho Chung. Potent inhibition of tumor relapse after anti-HER2 affibody tagged with cotinine (switch) plus anti-cotinine switchable CAR T cell therapy by repeated re-injection of the switch [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 6314.
Abstract 6362: The bispecific antibody KA-3002, targeting PSMA and 4-1BB, specifically enhances T cell activity within prostate tumors
Authors: Wu Guojin , Liang Jiabei , Peng Hao , Hao Feng , Liu Tongtong , Ning Jinying
Published: March 2024

Cancer immunotherapy with 4-1BB agonists has faced limitations in further clinical development due to dose-limiting toxicity. PSMA, highly expressed in normal prostate tissue and prostate cancer, is a clinically validated target for prostate cancer treatment. In this study, we developed a bispecific antibody (BsAb), KA-3002, targeting PSMA and human 4-1BB, with the aim of restricting 4-1BB stimulation to the interior of tumors. KA-3002 was developed based on our nanobody antibody discovery platform. KA-3002, in IgG1 format, features mutations in the Fc domain to eliminate ADCC, ADCP, and CDC activity. It contains two identical nanobodies at the C-terminal against 4-1BB to stimulate 4-1BB signaling in T cells and binds to PSMA with two Fabs at the N-terminal. KA-3002 exhibits high avidity binding to prostate tumor cells expressing PSMA (EC50<1nM) and also binds to 4-1BB expressed on 293T cells and activated human T cells. In the presence of a low concentration of CD3 antibody to stimulate T cell activation, co-culture of tumor cells expressing PSMA with primary T cells isolated from human PBMC enhances T cell activation and proliferation. In PBMC humanized immunodeficient mouse tumor models, KA-3002 effectively suppresses the growth of 22Rv1 tumors, which highly express PSMA. The antibody also demonstrates a half-life of more than five days in the blood of Balb/c mice. Finally, we assessed the developability of this antibody with different treatments such as high concentration, low pH, repeated freezing and thawing, and high temperature. KA-3002 shows neither aggregation nor degradation. In conclusion, the BsAb KA-3002, developed with our nanobody antibody discovery platform, emerges as a promising pre-clinical candidate drug for the treatment of prostate cancer.

Citation Format: Guojin Wu, Jiabei Liang, Hao Peng, Feng Hao, Tongtong Liu, Jinying Ning. The bispecific antibody KA-3002, targeting PSMA and 4-1BB, specifically enhances T cell activity within prostate tumors [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 6362.
Abstract 6365: The bispecific antibody KA-3008, targeting both EGFR and B7H3, increases internalization and minimizes on-target, off-tumor toxicity
Authors: Wu Guojin , Ding Li , Peng Hao , Hao Feng , He Feng , Ning Jinying
Published: March 2024

EGFR and B7H3 are highly expressed in various solid tumors, as well as in different normal tissues. Targeting EGFR or B7H3 alone with inhibitory monoclonal antibodies or antibody-drug conjugates (ADCs) may result in on-target, off-tumor toxicity. In this study, we developed a bispecific antibody (BsAb) named KA-3008, targeting both EGFR and B7H3 using our common light chain antibody discovery platform. KA-3008, in IgG1 format, features a regular antibody structure with an identical light chain, developed through knob-into-hole technology. Compared to its parent antibodies, its affinities for both EGFR and B7H3 decrease by more than ten times. It binds to cell lines expressing EGFR or B7H3 alone with an EC50 of more than 10nM, while it binds to cell lines expressing both EGFR and B7H3 with an EC50 of less than 1nM. KA-3008 also blocks the binding of EGF to EGFR and increases internalization when binding to both EGFR and B7H3 compared to binding to EGFR or B7H3 alone. In human tumor mouse models, KA-3008 effectively suppresses the growth of NCI-H1568 tumors expressing both EGFR and B7H3, but does not affect the growth of MS751 tumors that only highly express EGFR with low expression of B7H3. Additionally, KA-3008 has a half-life of more than five days in the blood of Balb/c mice. Finally, we assessed the developability of this BsAb with different treatments such as high concentration, low pH, repeated freezing and thawing, and high temperature, and KA-3008 shows neither aggregation nor degradation. In conclusion, the BsAb KA-3008, developed with our common light chain antibody discovery platform, is stable and holds potential for the development of ADCs targeting both EGFR and B7H3.

Citation Format: Guojin Wu, Li Ding, Hao Peng, Feng Hao, Feng He, Jinying Ning. The bispecific antibody KA-3008, targeting both EGFR and B7H3, increases internalization and minimizes on-target, off-tumor toxicity [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 6365.
Abstract 6465: A population-based analysis of brain metastasis burden and management in 8705 small cell lung cancer patients
Authors: Gaebe Karolina , Erickson Anders W. , Chen Sarah , Sahgal Arjun , Lok Benjamin H. , Chan Kelvin K. , Das Sunit
Published: March 2024

Introduction: Patients with small cell lung cancer (SCLC) have historically been characterized by poor overall survival (OS) and high risk for brain metastases (BM), but large-scale real-world evidence on clinical presentation and treatment in this population is lacking.

Methods: The aim of this study was to describe the clinical characteristics and outcomes of patients with SCLC and BM in Ontario, Canada. This retrospective cohort study included all patients in Ontario, Canada, who were diagnosed with SCLC between April 2010 and March 2018. Data were analyzed between June 2022 and July 2023. Kaplan-Meier and multivariable Cox regression analyses were performed to compare overall survival (OS) between patient cohorts stratified by disease stage, BM diagnosis, or first-line intracranial treatment modality.

Results: 8705 patients were included. Median age at diagnosis was 68 years (range 18-103). Median OS of all patients was 7.46 months (95% confidence interval, CI, 7.23-7.69). 32% (n=2686) of patients developed BM (synchronous, 43.7%; asynchronous, 56.3%) and had median OS of 9.76 months (95% CI, 9.36-10.22). 102, 1654, and 880 patients received stereotactic radiosurgery (SRS), whole brain radiation therapy (WBRT), and no treatment, respectively, for their BM in the first-line setting or after prophylactic cranial irradiation (PCI). In propensity score-matched analyses, OS was equivocal between SRS- and WBRT-treated cohorts among patients who did not receive PCI (hazard ratio, HR, 1.18, 95% CI, 0.75-1.81) and those who received PCI prior to BM development (HR, 0.77, 95% CI, 0.53-1.13).

Conclusions: Survival for patients with SCLC remains poor, and many patients present with BMs. With careful selection, patients with SCLC may benefit from SRS treatment.

Citation Format: Karolina Gaebe, Anders W. Erickson, Sarah Chen, Arjun Sahgal, Benjamin H. Lok, Kelvin K. Chan, Sunit Das. A population-based analysis of brain metastasis burden and management in 8705 small cell lung cancer patients [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 6465.
Abstract 6476: Solving the real-world data challenge: A hybrid resourcing model to curate RWD at scale
Authors: Rudolph Julia , Kehl Kenneth L. , Bernstein Melanie
Published: March 2024

Introduction: As cancer treatments become more complex, the need for structured real-world data (RWD) to support clinical research is critical. However, researchers often lack resources to curate data in-house. Organizations are challenged with timely data curation at the quality and scale needed for real world applications.

Methods: As members of the AACR Project GENIE (Genomics Evidence Neoplasia Information Exchange) Biopharma Collaborative (BPC), Memorial Sloan Kettering Cancer Center (MSK) and Dana-Farber Cancer Institute (DFCI) partnered with Vasta Global, an Omega Healthcare company, to build a model for curating RWD at scale, allowing for cost-effective RWD curation while leveraging expert resources and best practices. The approach includes managing a hybrid onshore and offshore team with clear communication and recurring check-ins, cross-training curators on different EHRs to reallocate Vasta Global resources and maintain project pace, building program-specific clinical data curation training, establishing QA and delivery methods, standardizing data curation, assigning productivity standards, aligning data quality practices and benchmarks, and developing data visualizations and analytics to show progress and insights.

Results: In Phase 1 of the AACR GENIE BPC, data was curated from four sites: MSK, DFCI, Vanderbilt Ingram Cancer Center (VICC) in Nashville, and Princess Margaret Cancer Centre, University Health Network (UHN) in Toronto. During Phase 1, MSK and DFCI, with Vasta Global’s assistance, delivered high-quality RWD for 6,475 patients (NSCLC = 1,591; CRC = 1,264; Bladder = 639; Breast = 957; Pancreas 989; and Prostate = 1,035). All data for these cohorts will be publicly available by Spring 2024 in the AACR Project GENIE cBioPortal. MSK and DFCI generated usable and fit-for-purpose RWD to help advance oncology clinical decision-making and data sharing.

Conclusion: Accelerating RWD curation will empower the oncology community to leverage data-driven insights and advance treatment opportunities for cancer patients. Working alongside lead sites, a partner like Vasta Global enables researchers to leverage extensive expertise in the BPC data model, allowing for consistency and scalability of the BPC program. In this hybrid model, research partners can curate RWD in a cost-effective way, while remaining focused on core research responsibilities.

Citation Format: Julia Rudolph, Kenneth L. Kehl, Melanie Bernstein. Solving the real-world data challenge: A hybrid resourcing model to curate RWD at scale [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 6476.
Abstract 649: SOX11 regulates BCR signaling via the PAX5/CD19 axis in MCL
Authors: Dutta Rudra Prasad , Lee Heng-Huan , Leshchenko Violetta V , Shukla Ravi Prakash , Liu Yang , Jin Jian , Wang Michael , Parekh Samir
Published: March 2024

Background: Mantle cell lymphoma (MCL) is an incurable lymphoid neoplasm, comprising about 6% of all non-Hodgkin lymphoma (NHL). The transcription factor SOX11 is overexpressed in the majority of MCL patients and linked to a more aggressive disease course and poorer clinical outcomes. In MCL, naïve B cells experience continuous proliferation because of the dysregulation of the B-cell receptor (BCR) pathway. Our previously published data (Kuo et. al., Blood 2018) identified that SOX11 aberrantly upregulated BCR signaling in transgenic mouse models. The current study describes the exact mechanism by which SOX11 regulates the BCR pathway using a combination of functional and pharmacological approaches.

Methods: To investigate the alterations in signaling pathways regulated by SOX11, we utilized a small molecule SOX11 inhibitor (Jatiani et. al., CCR 2021), performed CRISPR/CAS9 knockout of SOX11, 3X FLAG TAG overexpression, as well as conducted western blot and flow-cytometry experiments.

Results: Our prior published results (Kuo et. al., Oncogene 2015), as well as others (Vegliante et. al., Blood 2013), have shown that PAX5 is a direct target of SOX11. We confirmed PAX5 downregulation after SOX11 depletion in three human MCL cell lines (JEKO, MINO, Z138) using CRISPR-CAS9. Decrease of PAX5 expression was associated with reduction in CD19 expression and a concurrent reduction in phospho-BTK (Bruton tyrosine kinase). Conversely, overexpression of SOX11 could rescue PAX5/CD19 expression and restore p-BTK levels. Furthermore, the treatment of SOX11 expressing cells with small molecule SOX11-specific inhibitors resulted in a reduction in PAX5, CD19 and BCR activation (p-BTK).

Conclusion: Taken together, these findings delineate PAX5 as the direct target and PAX5/CD19 axis as the downstream pathway by which SOX11 regulates B-cell receptor (BCR) signaling in MCL. Notably, our treatment using a SOX11 inhibitor successfully replicated the effects observed with genetic knockdown. In conclusion, our findings provide valuable insights into the molecular mechanisms by which SOX11 contributes to MCL pathogenesis. The further development of pharmacological inhibitors targeting SOX11 holds promise as a beneficial therapeutic strategy for MCL patients, as these will block signaling upstream of current resistance mechanisms.

Citation Format: Rudra Prasad Dutta, Heng-Huan Lee, Violetta V Leshchenko, Ravi Prakash Shukla, Yang Liu, Jian Jin, Michael Wang, Samir Parekh. SOX11 regulates BCR signaling via the PAX5/CD19 axis in MCL [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 649.
Abstract 6520: Clinical verification oftherelationship betweenserum lipid metabolism andtumor immune microenvironment inpostmenopausal hormone receptor-positive/HER2-negative breast cancer patients
Authors: Goto Wataru , Matsuda Hanae , Henmi Saeko , Nishikawa Mariko , Kouchi Asuka , Kouhashi Rika , Yabumoto Akimichi , Takada Koji , Tauchi Yukie , Ogisawa Kana , Morisaki Tamami , Kashiwagi Shinichiro
Published: March 2024

Background: Recently, some basic research has reported that the tumor immune microenvironment (TIME) is related to the therapeutic efficacy and prognosis of breast cancer patients, and that the regulation of metabolism can affect TIME and enhance antitumor immunity. Suppression of aromatase expression from adipose tissue is the standard adjuvant endocrine therapy for postmenopausal hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer, but few studies have examined the impact of controlling lipid metabolism on TIME and cancer prognosis.

Materials and Methods: Except for patients with ductal carcinoma in situ, 531 postmenopausal HR-positive/HER2-negative breast cancer patients treated with curative surgery between 2011 and 2017 were examined. Serum lipid levels and systemic immune-related markers were evaluated by blood samples, and tumor-infiltrating lymphocytes (TILs) in cancer tissue samples were investigated by immunohistochemistry. We also examined the relationship between lipid metabolism, TIME, and prognosis, respectively.

Results: Good serum lipid control group was significantly correlated with low neutrophil- to-lymphocyte ratio (NLR) (p = 0.024) and high TILs (p = 0.039). The median follow-up time for the assessment of prognosis was 5.5 years, and 67 patients had recurrence. Only patients treated with aromatase inhibitor as adjuvant endocrine therapy showed significantly better recurrence-free survival (RFS) in the good lipid control group (p = 0.025, log-rank). Also, multivariate analyses showed that good serum lipid control was an independent prognostic factor for recurrence (HRs = 4.722, 95%CI: 1.006-22.161, p = 0.049). Patients with high CD8/FOXP3 ratio (CFR) had significantly better RFS (p=0.027, log-rank) and tended to have good lipid control.

Conclusions: Good control of serum lipid metabolism may inhibit the acquisition of resistance to endocrine therapy by improving TIME and induce favorable outcome in postmenopausal HR-positive/HER2-negative breast cancer patients.

Citation Format: Wataru Goto, Hanae Matsuda, Saeko Henmi, Mariko Nishikawa, Asuka Kouchi, Rika Kouhashi, Akimichi Yabumoto, Koji Takada, Yukie Tauchi, Kana Ogisawa, Tamami Morisaki, Shinichiro Kashiwagi. Clinical verification oftherelationship betweenserum lipid metabolism andtumor immune microenvironment inpostmenopausal hormone receptor-positive/HER2-negative breast cancer patients [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 6520.
Abstract 6532: Blockade of CD24 sensitizes pancreatic cancer to Kras inhibitors
Authors: Wei Yongkun , Liu Minghui , Yen Er-Yen , Yao Jun , Nguyen Phuoc T. , Wang Xiaofei , Yang Zecheng , Yousef Abdelrahman , Pan Dean , Jin Yanqing , Theady Madelaine S. , Park Jangho , Cai Yiming , Takeda Mitsunobu , Vasquez Matthew , Zhou Yong , Zhao Hong , Viale Andrea , Wang Huamin , Zhao Dan , DePinho Ronald A. , Yao Wantong , Ying Haoqiang
Published: March 2024

Pancreatic ductal adenocarcinoma (PDAC) is predominantly driven by KRAS oncogene. KRAS, long considered an undruggable target, has been targeted by drugs including a KRASG12C inhibitor (G12Ci), AMG 510, which is approved for the treatment of KRASG12C-mutant non-small cell lung cancer (NSCLC). AMG 510 also exhibited promising anticancer activity in human PDAC, with 21% response rate and over 70% patients experiencing certain level of tumor control. However, targeting KRAS oncogenes faces the major challenge of therapy resistance, which severely limited its survival benefit. While multiple studies have elucidated potential resistance mechanisms to G12Ci in lung cancer, the molecular mechanisms underlying resistance in PDAC remains elusive. Here, using KRASG12C-driven mouse PDAC model, we found that similar to the clinical observation, KRASG12C tumors exhibit only partial response to AMG 510 treatment. CyTOF analysis indicates that such tumor persistence following G12Ci treatment occurs even in the presence of conversion from a ‘cold’ pro-tumor immune microenvironment to a ‘hot’ anti-tumor immune environment, as evidenced by the prominent increase in both cytotoxic T cells and M1-like macrophages. Interestingly, we discovered that the expression of CD24, which was recently identified as a new ‘do not eat me’ signal, is significantly upregulated on the surface of persist tumor cells after G12Ci treatment which suppresses the function of anti-tumor macrophages. Anti-CD24 blocking mAb enhanced macrophage-mediated phagocytosis in vitro and significantly sensitizes KRASG12C tumors to AMG 510 treatment in vivo in a macrophage-dependent manner. Similar findings were observed in KRASG12D-driven PDAC model. Our findings identified a novel immune combination to improve the outcome of KRAS targeted therapy in PDAC.

Citation Format: Yongkun Wei, Minghui Liu, Er-Yen Yen, Jun Yao, Phuoc T. Nguyen, Xiaofei Wang, Zecheng Yang, Abdelrahman Yousef, Dean Pan, Yanqing Jin, Madelaine S. Theady, Jangho Park, Yiming Cai, Mitsunobu Takeda, Matthew Vasquez, Yong Zhou, Hong Zhao, Andrea Viale, Huamin Wang, Dan Zhao, Ronald A. DePinho, Wantong Yao, Haoqiang Ying. Blockade of CD24 sensitizes pancreatic cancer to Kras inhibitors [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 6532.