bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 389: Focal adhension kinase (FAK) confers lenvatinib resistance in hepatocellular carcinoma via regulation of lysine deficient protein kinase 1(WNK1)
Authors: Hou Wei , Gad Shaimaa A. , Qiu Wei 
Published: April 2023

Abstract
Lenvatinib is a clinically effective multi-kinase inhibitor approved for first-line therapy of advanced hepatocellular carcinoma (HCC). Although resistance against lenvatinib often emerges and limits its anti-tumor activity, the underlying molecular mechanisms involved in endogenous and acquired resistance are still unidentified. Endogenous (SNU449 and SNU475) and established acquired (Hep3B-LR and Huh7-LR) lenvatinib resistant cells, as well as knockout mice were used in this study. As a result, we recognized focal adhension kinase (FAK) as a critical contributor to lenvatinib resistance in HCC. The elevated expression of FAK was observed in both established and endogenous lenvatinib-resistant HCC cells. Furthermore, inhibition of FAK reversed lenvatinib resistance in vitro and in vivo. Mechanistically, FAK promoted lenvatinib resistance through regulating lysine deficient protein kinase 1 (WNK1) signaling pathway. WNK1 inhibitor WNK463 re-sensitized either established LR HCC cells (Hep3B-LR and Huh7-LR) or endogenous resistant HCC cells (SNU449 and SNU475) to lenvatinib treatment. In addition, overexpression of WNK1 desensitized parental HCC cells (Hep3B-P and Huh7-P) to lenvatinib treatment. Conclusively, our results establish a crucial role and novel mechanism of FAK in lenvatinib resistance, and suggest that targeting the FAK/WNK1 axis is a promising therapeutic strategy in HCC patients showing lenvatinib resistance.
Citation Format: Wei Hou, Shaimaa A. Gad, Wei Qiu. Focal adhension kinase (FAK) confers lenvatinib resistance in hepatocellular carcinoma via regulation of lysine deficient protein kinase 1(WNK1) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 389.
Abstract 3894: The role of ELF3 in acquired resistance to endocrine therapy in ER-positive breast cancer
Authors: Zhang Na , Zheng Rongbin , Brown Myles 
Published: April 2023

Abstract
Endocrine therapies targeting the estrogen receptor (ER) are the major treatments of ER+ breast cancer, however acquired resistance to endocrine therapy is almost unavoidable and is the main cause of death with breast cancer. The only FDA-approved selective estrogen receptor degrader (SERD) fulvestrant has been used in the second line treatment to overcome aromatase inhibitor- or tamoxifen-resistance. However, fulvestrant has poor pharmacokinetic properties, which has inspired the development of a new generation of oral SERDs including amcenestrant and giredestrant. To understand the mechanisms of acquired resistance to SERDs in ER+ breast cancer, we established ER+ breast cancer cell lines (MCF7 and T47D) resistant to fulvestrant, amcenestrant or giredestrant. We found that all of our MCF7 and T47D SERD-resistant cell lines showed cross-resistance to each of the three SERDs. We then performed multiple genome-wide profiling assays including CRISPR-KO screen, whole exome sequencing (WES), RNA-seq, ATAC-seq and H3K27ac ChIP-seq on the parental and SERD resistant cell lines. Our findings from the CRISPR-KO screens suggest that ETS transcription factor ELF3 is a potential driver of resistance to SERDs. ELF3 expression is negatively regulated by estrogen signaling. Cells that developed acquired resistance to different SERDs consistently show depletion of ER expression but also a dramatic increase of ELF3 expression, while knockdown of ELF3 in the resistant cells leads to cell growth inhibition, suggesting that ELF3 can drive cell survival in the SERD resistant cells. When comparing the open chromatin regions and active enhancer regions between SERD resistant and parental cells via ATAC-seq and H3K27ac ChIP-seq respectively, ELF3 DNA binding motif was found significantly enriched in SERD resistant cells versus parental cells further indicating that ELF3 may play an important role in the SERD resistant cells. ELF3 ChIP-seq was also performed to identify genes enriched with ELF3 binding sites in SERD resistant and parental cells. Pathway analysis of ELF3-targeted genes reveals that ELF3 may regulate cell metabolism specifically in SERD resistant cells but not in parental cells. Our study suggests that ELF3 may be a novel driver of acquired resistance to SERDs in ER+ breast cancer.
Citation Format: Na Zhang, Rongbin Zheng, Myles Brown. The role of ELF3 in acquired resistance to endocrine therapy in ER-positive breast cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3894.
Abstract 3909: THY1 regulates therapy resistance in glioblastoma recurrence
Authors: Shankar Sunita , Ravikumar Visweswaran , Wang Hanxiao , Ji Sunjong , Hasan Zainab , Fehmi Ziad , Haydin Yacoub , Wahl Daniel R. , Rao Arvind , Rehemtulla Alnawaz , Al-Holou Wajd 
Published: April 2023

Abstract
Glioblastoma (GBM), is the most common primary brain tumor. It is a lethal disease with a median survival of 15 months characterized by treatment resistance, aggressive brain invasion, and inevitable recurrence. Less than 10 percent of patients survive beyond 5 years. Here, we developed an intracranial longitudinal in vivo recurrence model using HF2303, a patient derived explant, to produce paired specimens (pre- and post-recurrence) following temozolomide(TMZ) and radiation(IR) treatment. Mouse brain tissues from the two groups were compared to identify genes and pathways driving treatment resistance. This analysis showed an elevated THY1 expression in recurrent HF2303 tumors compared to naïve tumors. Increased Thy1 expression was also associated with a more mesenchymal phenotype. THY1 expressing cells from naïve HF2303 were also resistant to TMZ/IR treatment in an intracranial model. In U87 neurospheres, overexpression of THY1 increased resistance to TMZ/IR. Interestingly, stable knockdown of Thy1 in GBM cells and human derived GBM organoids (GBOs) expressing high THY1 levels led to reduced cell proliferation. Yet, an inducible knockout of THY1 using CRISPR/Cas9 in human GBOs showed increased sensitivity to TMZ/IR. This suggests a clear link between THY1 expression and TMZ/IR resistance.Single cell RNA sequencing of over 25 primary GBM and 4 recurrent tumors (spanning over 120,000 cells) shows that cells expressing high levels of THY1 are associated with two distinct populations; neuronal precursor-like (NPC-like) and mesenchymal-like (MES-like). Furthermore spatial transcriptomics from 3 primary GBMs suggests that high THY1 expressing cells are colocalized with macrophages within the perivascular niche contributing to the mesenchymal phenotype. We will present these studies and our more recent work analyzing spatial recurrent GBM samples. Particularly, we will address how THY1 expression in these spatially distinct NPC-like and MES-like differ and how each of these states may contribute towards TMZ/IR resistance.
Citation Format: Sunita Shankar, Visweswaran Ravikumar, Hanxiao Wang, Sunjong Ji, Zainab Hasan, Ziad Fehmi, Yacoub Haydin, Daniel R. Wahl, Arvind Rao, Alnawaz Rehemtulla, Wajd Al-Holou. THY1 regulates therapy resistance in glioblastoma recurrence. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3909.
Abstract 391: Adenylosuccinate lyase enzyme is essential for growth of endocrine therapy resistant ER+ breast cancer cells
Authors: Yadav Anil K. , Clarke Robert , Sengupta Surojeet 
Published: April 2023

Abstract
The endocrine therapy (ET) that targets estrogen synthesis (aromatase inhibitors) or estrogen receptor mediated signaling (tamoxifen, or Fulvestrant) is the mainstay therapy for estrogen-receptor positive (ER+) breast cancer. However, emergence of resistance to ET is a major clinical challenge as it leads to relapse and disease progression that cannot be further treated with any targeted therapy. We studied the role of a key enzyme involved in de-novo purine biosynthesis, adenylosuccinate lyase (ADSL), in the growth and proliferation of ER+, ET-resistant breast cancer cells. ADSL enzyme is responsible for the catalysis of two non-sequential steps in de-novo purine synthesis pathway that produces aminoimidazole carboxamide ribonucleotide (AICAR) and adenosine monophosphate (AMP) as well as generates fumarate as a byproduct. Here we show that siRNA mediated depletion of ADSL in two different ER+, ET-resistant cell lines, namely LCC9 and T47D-4HT cells, block the proliferation of the cells in 2-D cell culture as well as in spheroid formation. Our investigation revealed that reduced growth of cells after ADSL-depletion was due to cell-cycle perturbation in both LCC9 and T47D-4HT cells and not cell death. Intriguingly, the cell cycle was blocked at different phases in LCC9 and T47D-4HT cells. After ADSL knock-down the LCC9 cells were arrested at G1/S boundary with concurrent elevated levels of cyclin D1 protein whereas the T47D-4HT cells were blocked at S/G2-M boundary with reduced levels of cyclin D1. In addition, we observed that ADSL deficient cells had low levels of ATP in conjunction with attenuated mitochondrial membrane potential. Notably, addition of low concentration of AICAR (but not AMP, adenosine, or fumarate) to ADSL deficient LCC9 cells partially rescue reduced proliferation of cells as well as restored the mitochondrial membrane potential. Our data establishes that ADSL enzyme function is critical for proliferation of ET-resistant ER+ breast cancer cells and its deficiency impair the mitochondrial function and energy production. We propose that ADSL is a potentially novel therapeutic target for ER+, endocrine therapy resistant breast cancer.
Citation Format: Anil K. Yadav, Robert Clarke, Surojeet Sengupta. Adenylosuccinate lyase enzyme is essential for growth of endocrine therapy resistant ER+ breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 391.
Abstract 3916: role of her3 v104l mutation on tumor growth and her3 stabilization
Authors: Mishra Rosalin , Kilroy Mary Kate , Feroz Wasim , Patel Hima , Alanazi Samar , Garrett Joan T. 
Published: April 2023

Abstract
We aimed to determine if naturally occurring HER3 mutations could drive oncogenic activity of HER2+ HCC1569 cells in which endogenous HER3 was knocked out using CRISPR-Cas9 technology. A series of HER3 mutations found in breast cancer patients (F94L, V104L, G284R, D297Y, T355I, and E928G) were introduced via lentiviral transduction and stable cell lines were generated in HER3 knock out (KO) HCC1569 cells and were maintained in 0.5 mg/mL puromycin. Our data indicated that cells stably transduced with HER3V104L mutation had significantly higher cell growth with higher p-HER3 expression versus wild-type (wt) and empty-vector (EV) HER3. We found that HCC1569HER3KO cells with WT and V104L were sensitive to increasing concentration of neratinib (0.1-0.5 µM) as indicated by crystal violet assay. Next we examined if V104L mutation rendered resistance to another FDA- approved irreversible HER2 tyrosine kinase inhibitor, tucatinib. Our results showed that V104L cells were sensitive to higher concentration of tucatinib compared to neratinib. In other experiments, we used COS7 cells to examine the signaling pathways of HER3V104L mutation. Our western blot data demonstrated that transient transfection of COS7 cells with HER3V104L mutant significantly upregulated p-HER3 and p-HER2 expression versus WT HER3 in a NRG- dependent manner. In addition, we found that the V104L mutation stabilizes HER3 protein expression independent of ligand stimulation. Our western blot data showed that V104L induced HER3 stabilization is independent on HER3 binding partners HER1, HER2 and HER4. Our cycloheximide chase data indicated that V104L mutation stabilizes HER3 expression in COS7 cells as well as low HER3 expressing colon cancer cell line, SNUC5. Our western blot data indicates that V104L mutation activates ERK signaling in NRG dependent manner over AKT pathway in COS7 cells. In addition, we are using various PDXs with different HER3 mutations (V104M and E928D) to determine the role of these driver HER3 mutations in cancer and how this can be targeted in the clinic using HER targeted therapy.
Citation Format: Rosalin Mishra, Mary Kate Kilroy, Wasim Feroz, Hima Patel, Samar Alanazi, Joan T. Garrett. role of her3 v104l mutation on tumor growth and her3 stabilization. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3916.
Abstract 3955: Functional evaluation of pancreatic cancer prognostic marker, LXN, utilizing multiomics analysis based on patient-derived cancer model
Authors: Park Chan Hee , Lee Hee Seung , Kim Jin Su , Tae Yoo Keung , Lee Jin Young , Bang Seungmin 
Published: April 2023

Abstract
Background: Pancreatic cancer is the most dreadful malignant tumor and expected becoming the second cause of death in 2030. Despites of vigorous studies, there were no definitive prognostic biomoleculars marker for pancreatic cancer. Herein, we already established primary pancreatic cancer cell lines from the real patients of pancreatic cancer, using conditionally reprogrammed cell culture (CRC). We tried to find novel prognostic biomarkers with multi-omics analysis of our primary pancreatic cancer cell lines.
Methods: In this study, we selected pancreatic cancer prognostic markers using established CRCs and FFPE samples and validated the molecular mechanism of LXN. As the first step, we performed both transcriptome and proteome analysis using RNA sequencing and liquid chromatography-tandem mass spectrometry (LC/MS-MS) with 6 primary pancreatic cancer cell lines established by CRC. After analysis, we mined several candidate markers of prognosis including latexin (LXN) and sialic acid acetylesterease (SIAE). And we validated these markers clinicopathologically using immunohistochemical (IHC) staining of 136 tissues from a different set of pancreatic cancer patients. And we confirmed the knock-down effect of LXN using siLXN in pancreatic cancer cells.
Results: We selected 2 highly prognostic markers with LXN and SIAE after transcriptome and proteome analysis. In these genes, high LXN expression group showed longer median overall survival (OS) than low expression group, respectively (14.8 vs. 10.4 months, P-value=0.28), respectively. For the evaluation of IHC, we established 3D organoid model using CRCs and confirmed the correlation between mRNA expression and protein expression with western blotting and IHC. The expression of Akt/mTOR was decreased after siLXN treatment compared to control groups. In order to validation as a prognostic marker, we stained formalin-fixed, paraffin-embedded (FFPE) slide from 136 pancreatic cancer patients. After IHC analysis, LXN high group (H-score &gt; 12) showed significantly longer OS than low LXN group (52 vs. 28 months, P-value = 0.043).
Conclusion: In this study, we found LXN as a prognostic marker with inhibition of proliferation utilizing patient-derived cancer model and FFPE samples.
Citation Format: Chan Hee Park, Hee Seung Lee, Jin Su Kim, Yoo Keung Tae, Jin Young Lee, Seungmin Bang. Functional evaluation of pancreatic cancer prognostic marker, LXN, utilizing multiomics analysis based on patient-derived cancer model. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3955.
Abstract 3956: Identifying PIKfyve as potential target in clear cell renal cell carcinoma with a loss of the von Hippel-Lindau tumor suppressor gene
Authors: Bouhamdani Nadia , Turcotte Sandra 
Published: April 2023

Abstract
Background. Clear cell renal cell carcinoma (ccRCC) is the most frequent type of cancer in the kidney. These tumors are highly vascular and correlate with poor prognosis. Biallelic inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene is a truncal event of ccRCC carcinogenesis, which yields new insights for targeted therapy. Our studies identified a small molecule, STF-62247, that is toxic to cells lacking VHL compared to RCC with a functional gene. We reported that STF-62247 blocks late stages of autophagy by targeting lysosome dynamics. Moreover, we identified lysosomal vulnerability in VHL-mutated ccRCCs, which could lead cells to death.
Goal. This study aims to recognize and characterize STF-62247 potential targets.
Results. Using biochemical approaches, our results indicated that STF-62247 cytotoxicity is driven by PIKfyve inhibition. Binding affinity between PIKfyve and STF-62247 is around 5 nM. Intracytoplasmic vacuoles and enlargement of endolysosomes were observed, which was prevented by adding exogenous PI(3,5)P2. Moreover, PIKfyve inhibitors such as apilimod, YM201636, Vacuolin-1, APY0201 sensitize ccRCC with a loss of VHL. Finally, genetic knockdown of PIKfyve was achieved by CRISPR/Cas9 leading VHL-inactivated cells to death.
Conclusion. Altogether, our studies identified, for the first time, PIKfyve as potential target for kidney cancer cells with a loss of VHL.
Citation Format: Nadia Bouhamdani, Sandra Turcotte. Identifying PIKfyve as potential target in clear cell renal cell carcinoma with a loss of the von Hippel-Lindau tumor suppressor gene. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3956.
Abstract 4015: EGFR activation via c-Jun axis promotes adaptive resistance to third generation ALK-TKI lorlatinib in ALK-rearranged non-small cell lung cancer cells
Authors: Katayama Yuki , Yamada Tadaaki , Morimoto Kenji , Ozasa Hiroaki , Tokuda Shinsaku , Takayama Koichi 
Published: April 2023

Abstract
Anaplastic lymphoma kinase-tyrosine kinase inhibitors (ALK-TKIs), including lorlatinib have shown dramatic efficacy in patients with ALK-rearranged lung cancer; however, complete response in these patients is rare, as a small population of tumor cells survives due to adaptive resistance. In this preclinical study, we investigated the adaptive resistant mechanisms to lorlatinib and its therapeutic strategies to overcome, using in vitro and in vivo experiments. We have identified EGFR as an adaptive resistance mechanism of lorlatinib using phospho-RTK array and siRNA library. Cell line-based assay showed that exposure of lorlatinib accelerated EGFR signal activation as an adaptive response via activation of JNK cascade in ALK-rearranged lung cancer cells. Knockdown for EGFR suppressed the survival signal of ALK lung cancer cells when treated with lorlatinib. The combination of lorlatinib and erlotinib, a first-generation EGFR-TKI, was shown to enhance cell growth inhibition by inducing cell apoptosis via suppressing the anti-apoptotic factor Bcl-xl compared with lorlatinib monotherapy. Moreover, cell line-derived xenograft model indicated that the combination of lorlatinib plus erlotinib enhanced anti-tumor effects compared with lorlatinib monotherapy. Taken together, our results displayed that EGFR activation plays an important role in the initial adaptive resistance to lorlatinib for ALK-rearranged lung cancer. The combination of lorlatinib and erlotinib is expected as the promising strategy for those tumors.
Citation Format: Yuki Katayama, Tadaaki Yamada, Kenji Morimoto, Hiroaki Ozasa, Shinsaku Tokuda, Koichi Takayama. EGFR activation via c-Jun axis promotes adaptive resistance to third generation ALK-TKI lorlatinib in ALK-rearranged non-small cell lung cancer cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4015.
Abstract 4083: In vivo efficacy of LGR5-targeting CAR-T cell therapies developed for the treatment of colorectal cancer
Authors: McPeake Dylan , Tyllis Timona , Abbott Caitlin , Foeng Jade , Bandara Veronika , Gundsambuu Batjargal , Rohani-Rad Elaheh , Napoli Silvana , Sadlon Timothy , Barry Simon , McColl Shaun 
Published: April 2023

Abstract
While CAR-T cells have demonstrated significant efficacy in the treatment of haematological malignancies, there are many challenges to overcome in developing CAR-T cell therapies against solid tumours. In particular, the scarcity of recognised effective target antigens in solid tumours remains a significant hurdle. Leucine-rich repeat-containing G-protein coupled receptor (LGR5) is a cancer stem cell marker, which mediates important roles in tumor initiation and metastasis. Upregulated LGR5 expression in malignant cell contexts highlights this surface receptor as a promising target for CAR-T cell therapy. In this study, we evaluated the efficacy of LGR5-targeting CAR-T cells against a range of human cancers. We demonstrate that LGR5 is expressed, both in vitro and in vivo, by numerous human cancers, including colorectal, ovarian, hepatic, brain, and pancreatic cancer. LGR5-targeting CAR-T cells effectively kill LGR5-expressing cancer cells in in vitro cytotoxicity assays and display significant anti-tumor activity in vivo when administered at 1, 2 or 3 weeks post-tumor inoculation in a subcutaneous human colorectal cancer xenograft mouse model. Furthermore, LGR5-targeting CAR-T cells that induce primary tumor rejection confer complete protection against a secondary tumor challenge 5 weeks post-T cell transfer. In vivo spatiotemporal distribution and repeated dosing studies demonstrate that LGR5-targeting CAR-T cells accumulate at the tumor site until tumor elimination, do not persist in off-target organs by d28 post-tumor inoculation and are safe and well-tolerated under the conditions tested. Together, these results provide the foundation for furthering the development of LGR5-targeting CAR-T cells for use in the clinic against colorectal cancers and other solid tumours.
Citation Format: Dylan McPeake, Timona Tyllis, Caitlin Abbott, Jade Foeng, Veronika Bandara, Batjargal Gundsambuu, Elaheh Rohani-Rad, Silvana Napoli, Timothy Sadlon, Simon Barry, Shaun McColl. In vivo efficacy of LGR5-targeting CAR-T cell therapies developed for the treatment of colorectal cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4083.