bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 1739: Detection of regulatory T cells, a comparison of flow cytometry and epigenetic qPCR immunophenotyping using healthy donor and oncology patient whole blood
Authors: Baron Udo , Lozza Laura , Bisconte Angelina , Raschke Eva , Phippard Deborah , Olek Sven 
Published: March 2024

Abstract
Human regulatory T cells (Tregs) are part of the adaptive immune response and play a pivotal role in suppressing both the immune and anti-tumor responses. Infiltration of Tregs into the tumor microenvironment has been associated with poor clinical prognosis. In addition, increased peripheral Treg frequency is associated with disease progression. Monitoring Tregs in both the blood and in the tumor of patients is being used to evaluate clinical prognosis and response to treatment in immuno-oncology studies. The key challenge is the ability to detect Tregs with high accuracy and precision. Here, we have used epigenetic qPCR (Epiontis ID®) as a method to detect and quantify Tregs in peripheral whole blood and compared it with flow cytometry. Flow cytometry is the current gold standard for immunophenotyping. For method comparison, we analyzed 113 whole blood samples from healthy donors. We have demonstrated equivalence and shown a strong correlation between epigenetic qPCR and flow cytometry-based data, indicating that Epiontis ID® is a robust and sensitive DNA-based method for Treg quantification. This epigenetic qPCR method does not require fresh samples or intact cells, since DNA can be extracted from frozen blood. We then evaluated Treg levels in blood samples from solid tumor cancer patients by epigenetic qPCR to demonstrate the clinical application and relevance for immune monitoring. Here, Treg frequencies were reported as relative (%) and absolute counts (cells/µL) values. Epigenetic qPCR for immune monitoring mitigates the operational and technical challenges of monitoring Tregs in the periphery for immuno-oncology studies which traditionally been performed by flow cytometry. This Epiontis ID® method provides the sensitivity and accuracy needed for determining patient response in progressive disease.
Citation Format: Udo Baron, Laura Lozza, Angelina Bisconte, Eva Raschke, Deborah Phippard, Sven Olek. Detection of regulatory T cells, a comparison of flow cytometry and epigenetic qPCR immunophenotyping using healthy donor and oncology patient whole blood [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 1739.
Abstract 1753: SHOC2 is a genetic dependency in NRAS-mutant melanoma
Authors: Gu Andrea Y. , Lee Tet-Woo , Khan Aziza , Hunter Francis W. , Singleton Dean C. , Jamieson Stephen M. F. 
Published: March 2024

Abstract
Melanoma is the most lethal form of skin cancer, with over 300,000 new cases worldwide every year. Specifically, melanoma with NRAS mutations are of particular clinical concern due to their association with a poor prognosis and lack of specific treatment options. Therefore, there is a pressing need for novel approaches to address the treatment of NRAS-mutant melanoma. A current approach to identify novel drug targets is based on the genetic concept of induced essentiality, where functional interactions that occur in response to oncogene addiction create a dependency on another gene. To identify genetic dependencies in NRAS-mutant melanoma, whole-genome CRISPR-Cas9 knockout screens were conducted in 6 NRAS-mutant and 7 NRAS-wild-type (wt) early-passage New Zealand melanoma (NZM) cell lines that were established and maintained at 5% oxygen to mimic physiological oxygen conditions. The NZM cell lines were stably transduced with the whole-genome Brunello lentiviral single guide (sg) RNA library and screened for up to 35 days. BAGEL (Bayesian Analysis of Gene Essentiality) analyses of the NZM whole-genome knockout screens, alongside CRISPR-Cas9 screening data using the Avana sgRNA library from an additional 28 melanoma cell lines, available on the Cancer Cell Line Encyclopaedia (CCLE) database, revealed prospective gene candidates that exhibit greater detrimental effects on the fitness of NRAS-mutant cell lines compared to the NRAS-wt lines. These genes are being further validated as essential genes for NRAS-mutant melanoma cells through custom sgRNA library knockout screens and in vitro individual gene knockout studies. In particular, we demonstrate that knockout of SHOC2, a gene that encodes a scaffold protein essential for activation of the MAPK signalling pathway, results in the prevention of ERK phosphorylation and a more substantial reduction in cell growth in NRAS-mutant NZM cell lines when compared to NRAS-wt lines. These results support previous studies that have identified SHOC2 as a potential therapeutic target for RAS-driven cancers and suggest that targeting of SHOC2 may have utility in NRAS-mutant melanoma, where greater treatment options are urgently needed.
Citation Format: Andrea Y. Gu, Tet-Woo Lee, Aziza Khan, Francis W. Hunter, Dean C. Singleton, Stephen M. F. Jamieson. SHOC2 is a genetic dependency in NRAS-mutant melanoma [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 1753.
Abstract 1798: Glyoxalase 1 (GLO1) as an oncometabolic enabler of prostate cancer progression: CRISPR/Cas9-based GLO1-deletion from human DU145-Luc2 cells blocks EMT and bone metastasis in SCID mice
Authors: Jandova Jana , Cress Anne E. , Wondrak Georg T. 
Published: March 2024

Abstract
Glyoxalase 1 (encoded by GLO1) is a glutathione-dependent enzyme detoxifying the glycolytic byproduct methylglyoxal (MG), an oncometabolite involved in metabolic reprogramming. Recently, we have demonstrated that GLO1 is overexpressed in human prostate cancer cells and patient tumors. In order to inform the ongoing debate on the role of GLO1 as an oncometabolic enabler of tumor glucose metabolism and malignant progression, we performed CRISPR/Cas9-based GLO1-deletion in human DU145-Luc2 malignant prostate cancer cells. NanoString nCounterTM ('PanCancer-Progression-Panel') comparative gene expression profiling (GLO1_KO versus GLO1_wt) revealed a significant downregulation of EMT-related pathways in GLO1_KO cells; concordantly, phenotypical screening indicated a pronounced attenuation of matrigel invasiveness observable in GLO1_KO cells. Likewise, inclusion of MG or a small molecule GLO1 inhibitor (TLSC-702) blocked invasiveness of DU145 GLO1_wt cells. Downregulation of EMT-related genes (including MMP3, SPP1, CXCL8) was accompanied by increased expression of TXNIP (thioredoxin-interacting protein), a master regulator of cellular energy metabolism and redox homeostasis. In a bioluminescent SCID mouse bone metastasis model (intracardial injection of DU145-Luc2 GLO1_wt and GLO1_KO cells), GLO1 expression was necessary to cause mandibular bone metastases (as evidenced by the complete absence of bone metastases after GLO1 deletion). Given the availability of drug-like small molecule inhibitors of GLO1 enzymatic activity these data suggest that GLO1 represents a novel molecular target for the pharmacological suppression of prostate cancer bone metastasis.
Citation Format: Jana Jandova, Anne E. Cress, Georg T. Wondrak. Glyoxalase 1 (GLO1) as an oncometabolic enabler of prostate cancer progression: CRISPR/Cas9-based GLO1-deletion from human DU145-Luc2 cells blocks EMT and bone metastasis in SCID mice [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 1798.
Abstract 1945: Mechanisms of acquired resistance to EGFR tyrosine kinase inhibitor osimertinib and KRAS-G12C inhibitor sotorasib in lung cancer
Authors: Yagami Yuri , Sato Takashi , Yamamoto Hiroki , Shirasawa Masayuki , Nakahara Yoshiro , Hideo Watanabe , Katsuhiko Naoki 
Published: March 2024

Abstract
A series of molecular targeted drugs have been developed for the treatment of non-small cell lung cancer (NSCLC) harboring driver gene alterations. Although the use of these drugs has substantially improved the clinical outcomes of patients with the genetically altered NSCLC, these patients ultimately develop resistance to the drugs. Various molecular mechanisms of resistance to the molecular target therapies have been reported, it is still a crucial challenge to overcome the drug resistance. Osimertinib, the most used third-generation EGFR tyrosine kinase inhibitor to target both common EGFR mutations and secondary T790M mutation, and sotorasib, a recently developed KRAS inhibitor to target KRAS G12C mutation, are no exception. In this study, we aimed to investigate the mechanisms of acquired resistance to osimertinib and sotorasib in NSCLC by profiling drug-resistant lung cancer cell lines, which were established from EGFR-mutant HCC827(del E756_A750) and KRAS G12C-mutant H23 through exposure to each of the molecular targeted drugs. Phospho-RTK array and western blot analyses revealed MET overexpression and phosphorylation in the osimertinib-resistant HCC827 (HCC827OR) as previous studies reported. Notably in our study, HCC827OR cells were incompletely sensitive to a selective MET inhibitor savolitinib without osimertinib, suggesting that HCC827OR partially lost its dependency on mutant EGFR and got addiction to MET signaling. When sotolasib was administered to the sotolasib-resistant H23 (H23SR) cells, KRAS-GTP, and the downstream ERK and AKT phosphorylation were suppressed. To identify novel mechanisms of the resistance, we performed epigenomic profiling of active enhancer in those cells and found a candidate transcription factor, at whose gene locus H3K27 acetylation signal was increased in H23SR cells compared to parent H23 cells. Immunoblotting showed that protein expression of the gene was indeed higher in H23SR cells than the parent cells. To confirm the involvement of this gene to the resistance, further investigation is warranted.
Citation Format: Yuri Yagami, Takashi Sato, Hiroki Yamamoto, Masayuki Shirasawa, Yoshiro Nakahara, Watanabe Hideo, Naoki Katsuhiko. Mechanisms of acquired resistance to EGFR tyrosine kinase inhibitor osimertinib and KRAS-G12C inhibitor sotorasib in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1945.
Abstract 1953: Posttranslational modification in glucocorticoid receptor in treatment resistant prostate cancers
Authors: Gulla Surendra , Gardner Ephraim , Sundar Shreya Shyam , Jaiswal Praveen , Gao Ning , Bennet Lynda , Conzen Suzanne , Adelaiye-Ogala Remi 
Published: March 2024

Abstract
Prostate Cancer (PCa) remains the most common cancer in men in the United States and the second leading cause of cancer-related death in men. An evolving concept that contributes to our understanding of resistance to androgen deprivation therapy (ADT) and AR antagonists in advanced PCa is the ability of cells to turn on compensatory hormone receptor signaling for survival. Preclinical and clinical studies demonstrate that induction of glucocorticoid receptor (GR) expression confers resistance to AR-targeted therapy. Previous studies from our lab demonstrated that the inhibition of AKT signaling blocks pro-oncogenic GR activity and overcomes resistance to AR-targeted therapy. AKT1 is predicted to phosphorylate GR at s134, however, the implications of pGR(s134) in advanced PCa remains unclear. Although ligands (e.g., Dex) activates GR, we have found GR activation modulated by post-translational modification (PTM) and persistent in treatment resistant PCa. Therefore, we hypothesize pro-oncogenic GR activation through AKT1-induced PTM. The rationale is that by inhibiting AKT signaling, we block residual GR signaling that can potentially drive lethal prostate cancers and consequently be re-sensitized to the standard of care. We validated our findings by Western blot analysis, we used an AKT1-specific inhibitor (AKT1i) and observed decreased AKT1 activity and decreased pGR(s134) without affecting total GR protein expression. Functional studies using shRNA against AKT1 showed reduced pGR(s134) expression without affecting the total GR expression Our preliminary data suggests that pro-oncogenic GR activity is modulated through the phosphorylation of GR on s134 by AKT1.
Citation Format: Surendra Gulla, Ephraim Gardner, Shreya Shyam Sundar, Praveen Jaiswal, Ning Gao, Lynda Bennet, Suzanne Conzen, Remi Adelaiye-Ogala. Posttranslational modification in glucocorticoid receptor in treatment resistant prostate 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 1953.
Abstract 1967: IN-119873, the next-generation allosteric EGFR TKI, a potent and highly selective EGFR L858R for the treatment of osimertinib-resistant NSCLC
Authors: Choi Jong Ryoul , Yoon Daseul , Kim Seo Hyun , Kim Do Gyeong , Kang Seock Yong , Choi Seong-Il , Park Somyi , Lee Hyun Kyung , Kim Donghyun , Lee Ju Hyun , Kim Hye-Jung , Kim Bong Tae 
Published: March 2024

Abstract
EGFR mutations occur in approximately 50% of Asian patients and 20% of Caucasian patients with non-small cell lung cancer (NSCLC). The EGFR L858R mutation constitutes approximately half of the EGFR-mutated patients, and despite receiving first-line or second-line treatment with the 3rd generation EGFR TKI osimertinib, they continue to exhibit a poor prognosis. According to real-world analysis, the leading resistance mechanism to osimertinib is identified as EGFR C797S mutation. Furthermore, osimertinib is still associated with gastrointestinal and skin toxicity, despite its improved selectivity for EGFR WT compared to 1st-generation EGFR TKIs. Here, we show that IN-119873 can overcome C797S-mediated acquired resistance based on the results obtained by various in vitro and in vivo NSCLC models. IN-119873 binds to an EGFR allosteric site separate from the ATP-binding site with a remarkable preference for highly mutant-selective inhibition. It effectively targets EGFR L858R activating mutations while sparing the inhibition of EGFR WT, which sets it apart from ATP competitive inhibitors. Moreover, oral administration of IN-119873 showed excellent anti-tumor efficacy in a dose-dependent manner in a diverse of osimertinib-resistant CDX and PDX models. IN-119873 also demonstrated favorable blood-brain-barrier penetration with promising intracranial efficacy in the H1975-luc brain metastasis model both mono or in combination with osimertinib. As a selective, orally available, and CNS-penetrable next-generation allosteric EGFR-TKI, IN-119873 is currently undergoing IND-enabling studies and has the potential to demonstrate activity in both first-line and resistance settings, either as a monotherapy or in combination with 3rd generation EGFR TKI.
Citation Format: Jong Ryoul Choi, Daseul Yoon, Seo Hyun Kim, Do Gyeong Kim, Seock Yong Kang, Seong-Il Choi, Somyi Park, Hyun Kyung Lee, Donghyun Kim, Ju Hyun Lee, Hye-Jung Kim, Bong Tae Kim. IN-119873, the next-generation allosteric EGFR TKI, a potent and highly selective EGFR L858R for the treatment of osimertinib-resistant NSCLC [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 1967.
Abstract 1969: Off-target autophagy inhibition by SHP2 allosteric inhibitors and therapeutic implications for aberrant RAS-driven cancers
Authors: Miao Yiming , Bai Yunpeng , Miao Jinmin , Murray Allison A. , Lin Jianping , Dong Jiajun , Qu Zihan , Zhang Ruo-Yu , Nguyen Quyen , Wang Shaomeng , Zhang Zhong-Yin 
Published: March 2024

Abstract
Aberrant activation of RAS-MAPK signaling is common in cancer, and efforts to inhibit pathway components have yielded drugs with promising clinical activities. Unfortunately, treatment-provoked adaptive resistance mechanisms inevitably develop, limiting their therapeutic potential. As a central node essential for receptor tyrosine kinase mediated RAS activation, SHP2 has emerged as an attractive cancer target. Consequently, many SHP2 allosteric inhibitors are now in clinical testing. Here we discovered a previously unrecognized off-target effect associated with SHP2 allosteric inhibitors. We found that these inhibitors accumulate in the lysosome and block autophagic flux in a SHP2-independent manner. We showed that off-target autophagy inhibition by SHP2 allosteric inhibitors contributes to their anti-tumor activity. We also demonstrated that SHP2 allosteric inhibitors harboring this off-target activity not only suppress oncogenic RAS signaling but also overcome drug resistance such as MAPK rebound and protective autophagy in response to RAS-MAPK pathway blockage. Finally, we exemplified a new therapeutic framework that harnesses both the on- and off-target activities of SHP2 allosteric inhibitors for improved treatment of mutant RAS driven and drug resistant malignancies such as pancreatic and colorectal cancers.
Citation Format: Yiming Miao, Yunpeng Bai, Jinmin Miao, Allison A. Murray, Jianping Lin, Jiajun Dong, Zihan Qu, Ruo-Yu Zhang, Quyen Nguyen, Shaomeng Wang, Zhong-Yin Zhang. Off-target autophagy inhibition by SHP2 allosteric inhibitors and therapeutic implications for aberrant RAS-driven 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 1969.
Abstract 1996: Novel mechanism of temozolomide resistance in glioblastoma
Authors: Hung Yuet Yi Charmaine , Kiang Mei Yee Karrie , Leung Ka Kit Gilberto 
Published: March 2024

Abstract
Intrinsic expression of PD-1 has been discovered in different types of tumurs, exhibiting either oncogenic or tumor-suppressing function. In glioblastoma (GBM), intrinsic PD-1 has been found to play a role in promoting the proliferation and self-renewal of brain tumor-initiating cells through nuclear factor κB without involving PD-L1 ligation, with unknown factors activating this signalling pathway. Meanwhile, TMZ resistance significantly contributes to treatment failure and an extremely poor prognosis for GBM. This study investigated whether intrinsic PD-1 is also expressed in differentiated human GBM cell lines and its role in GBM proliferation and temozolomide (TMZ) resistance. In vitro studies demonstrated the presence of PD-1 in both U87 and U251 TMZ-sensitive and -resistant cell lines, with a higher expression on TMZ-resistant cell lines. PDCD1 knockdown led to decreased GBM progression, including cell proliferation, colony formation and cell migration, in TMZ-resistant U87 and U251 cell lines using cell viability assays. It also resensitizes these cell lines to TMZ. Overexpression of PDCD1 in the PDCD1-knockdown cell lines increases their proliferation and restores their resistance to TMZ. Treatment of U87 and U251 TMZ-resistant cell lines with TMZ upregulated PD-1 expression. An orthotopic xenograft mouse model is further deployed by injecting previously cultured U87 and U251 cell lines into the mouse brains. A smaller tumour size is observed in the model with PDCD1 knockdown model than the one without PDCD1 knockdown when treated with TMZ. This study reveals that intrinsic PD-1 expression contributes to TMZ resistance in GBM and TMZ may be a factor activating the PD-L1-independent PD-1 signalling. PD-1 and its downstream signalling pathway, such as SHP-2 and IKK, may be potential therapeutic targets for GBM patients with TMZ resistance. Co-administration of TMZ and agents inhibiting the intrinsic PD-1 signalling pathway can potentially produce synergistic therapeutic effects. The higher expression of PD-1 on TMZ-resistant GBM than on TMZ-sensitive GBM also suggests that the intrinsic PD-1 level can be a predictor of TMZ outcome.
Citation Format: Yuet Yi Charmaine Hung, Mei Yee Karrie Kiang, Ka Kit Gilberto Leung. Novel mechanism of temozolomide resistance in glioblastoma [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 1996.
Abstract 1998: ABCB1 promotes uveal melanoma cell resistance to FR900359 and identifies a tumor cell subpopulation with a distinct gene expression signature
Authors: Murray Sarina Dion , Riordan Jesse D. , Anderson Eric R. , Onken Michael D. , Blumer Kendall J. , Dupuy Adam J. , Stipp Christopher S. 
Published: March 2024

Abstract
Uveal melanoma (UM) is the leading form of intraocular cancer in adults and the second most common form of melanoma. Although rare, UM has a median survival rate of ~1 year after metastasis occurs. Metastatic UM is largely refractory to treatment and there are no effective pharmacological therapies, resulting in poor overall survival. In &gt;90% UM cases, the oncogenic initiator proteins are constitutively active mutant GNAQ or GNA11 proteins (GNAQ/11). FR900359 (FR) is a natural compound that inhibits GNAQ/11 and has anti-proliferative effects on UM cells. To identify key oncogenic mechanisms downstream of mutant GNAQ/11, we performed a Sleeping Beauty (SB) transposon forward genetic screen to identify drivers of FR resistance. The SB screen identified ATP-binding cassette sub-family B member 1 (ABCB1) as one of the top genes upregulated by SB in FR-resistant UM cell populations. We determined that although ABCB1 does not provide immediate resistance to FR, the overexpression of ABCB1 leads to emergence of resistant colonies at a much higher rate than spontaneous resistance, validating ABCB1 as contributors to FR resistance. Unexpectedly, immunofluorescence revealed that a relatively small fraction of UM cells strongly expresses the transgenes after stable transfection. Immunoblotting confirmed that ABCB1 expression was initially modest in ABCB1-transfected populations but increased in the cells that developed resistance to FR. To examine the kinetics of FR resistance, population doubling versus time (PDVT) assays were performed in UM cells expressing ABCB1 or empty vector control treated with FR or vehicle. FR potently suppressed the proliferation of vector control cells. Drug-naïve ABCB1-transfected cells developed resistance to FR over time but accomplished fewer population doublings than vehicle-treated cells in the same time interval. Once transgenic populations emerged as resistant populations in FR, they grew similarly in drug or vehicle. Ongoing RNA-sequencing analysis from PDVT samples has identified distinct gene expression signatures associated with FR treatment and ABCB1 expression. These findings are expected to illuminate tumor cell heterogeneity amongst UM cell populations that may be related to drug resistance and metastasis.
Citation Format: Sarina Dion Murray, Jesse D. Riordan, Eric R. Anderson, Michael D. Onken, Kendall J. Blumer, Adam J. Dupuy, Christopher S. Stipp. ABCB1 promotes uveal melanoma cell resistance to FR900359 and identifies a tumor cell subpopulation with a distinct gene expression signature [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 1998.