bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2358: Impact pathway analysis of FOXC2-correlated genes in melanoma: A meta-analysis approach to understand the tumor-promoting functions of the FOXC2 transcription factor
Authors: Wall James B. , Hargadon Kristian M. 
Published: June 2022

Abstract
Melanoma is a cancer that arises from pigment-producing melanocytes in the skin. Because of the increasing incidence of melanoma and its resistance to many therapies, insights into melanoma progression are needed. FOXC2, a member of the forkhead box family of transcription factors, has been shown to have oncogenic activity in many epithelial cancer types, and we have recently reported a role for FOXC2 in melanoma progression as well. To gain insight into the role of FOXC2 in melanoma progression, we analyzed publicly available RNA-sequencing data from tumor biopsies of melanoma patients, including a cohort of 479 patients catalogued in The Cancer Genome Atlas as well as additional cohorts from other independent studies. We performed Spearman correlation analyses to identify genes positively and negatively co-expressed with FOXC2, and we performed Impact Pathway Analysis and Gene Ontology Analysis to determine which biological pathways and processes are most impacted by FOXC2-associated genes in melanoma. Our data highlight critical pathways impacted by the expression of FOXC2, and they identify specific genes influenced by this transcription factor that provide mechanistic insight into the oncogenic activity of FOXC2 in melanoma and potentially other cancers.
Citation Format: James B. Wall, Kristian M. Hargadon. Impact pathway analysis of FOXC2-correlated genes in melanoma: A meta-analysis approach to understand the tumor-promoting functions of the FOXC2 transcription factor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2358.
Abstract 2361: MYC-driven breast cancer tumorigenesis is dependent on normal mitochondrial function
Authors: Moyer Sydney M. , Ilic Nina , Gang Sydney , Arnoff Taylor E. , Hahn William C. 
Published: June 2022

Abstract
While the transcription factor MYC is amplified in all breast cancer subtypes, nearly 60% of patients with triple-negative tumors have elevated MYC copy number and expression. Patients with triple-negative breast cancer (TNBC) typically have increased metastasis, decreased response to therapies, and poor outcomes, highlighting MYC’s causal association with disease aggressiveness and low survival rates. Unfortunately, MYC is not considered directly pharmacologically tractable. Therefore, we sought to identify collateral “genetic dependencies,” downstream of oncogenic MYC. Using comparative genome-scale CRISPR/Cas9 screening in isogenic human mammary epithelial cells (HMECs), we have identified two mitochondrial membrane transporter genes, TIMM17A and MTCH2, specifically required for MYC-dependent proliferation and survival.
Since MYC is suspected to drive metabolic reprogramming in cancers, we assessed how MYC affected mitochondrial protein content by quantitative mass spectrometry. This revealed an increase in N-acetylaspartate (NAA) in HMECs with MYC amplification compared to other genetic backgrounds. Interestingly, increased NAA levels are dependent on TIMM17A and MTCH2 presence. Loss of either of these genes results in cell death coupled with decreased NAA. NAA supplementation in the media of MYC-HMECs following loss of TIMM17A or MTCH2 can rescue the cell death. Importantly, NAA supplementation in cells with guides targeting GFP (negative control) or general essential gene RPL11 did not show increased cell growth/viability - showing that the NAA supplementation is specifically compensating for loss of mitochondrial transport function in MYC-HMECs.
Based on these data, it appears that MYC-amplified TNBCs are uniquely dependent on TIMM17A and MTCH2 mitochondrial transporter function because they drive metabolic reprogramming resulting in addiction to N-acetylaspartate production. To conclude these studies, we are evaluating the dependence on mitochondrial transport and NAA synthesis in MYC-amplified TNBCs by assessing the function of TIMM17A and MTCH2 as MYC-specific genetic dependencies in patient derived xenografts of TNBC and determining if TNBCs are addicted to increased NAA synthesis by overexpressing aspartoacylase to breakdown NAA. Successful completion of this work will provide novel drug targets required for survival of aggressive MYC-amplified breast cancers.
Citation Format: Sydney M. Moyer, Nina Ilic, Sydney Gang, Taylor E. Arnoff, William C. Hahn. MYC-driven breast cancer tumorigenesis is dependent on normal mitochondrial function [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2361.
Abstract 2365: Mechanisms of mutant p53 targeting to the genome
Authors: Metcalf Stephanie , Morris Stevie , Hollenhorst Peter 
Published: June 2022

Abstract
Mutations in genes often result in tumor formation, especially when these mutations occur in tumor suppressors. TP53 is a tumor suppressor that is frequently mutated in cancer, with mutations in this gene occurring in nearly 50% of all cancer cases. Once mutated, p53 loses its tumor suppressive function while simultaneously gaining oncogenic function. One of the functions that mutant p53 loses is the ability to directly bind to chromatin, however, it has been reported that mutant p53 can still affect the transcriptome of cancer cells via interactions with other transcription factors. One of these interacting partners is ETS2. ETS2 belongs to the ETS transcription factor family, which has 28 family members. This family is characterized by their affinity for an ETS binding site (EBS). EBS’s are present in 50% of all mutant p53 occupied promoters. Other ETS family members have also been linked to mutant p53 but these interactions have either been deemed as weak (ETS1) or have yet to be identified as direct (ERG). To determine which ETS proteins interact with mutant p53 I conducted affinity pull-down assays using purified ETS proteins and purified mutants of p53. My data shows that several ETS proteins interact with mutant p53 better than ETS2. I then sought to determine which residues are important for this interaction through truncation studies in which I used purified truncations of ETS proteins and purified mutants of p53. I found that ERG, one protein that strongly interacted with mutant p53, had two interaction interfaces. This may explain why the interaction is strong. My next step was to determine which ETS proteins are responsible for the targeting of mutant p53 to the genome. To address the requirement for ETS to recruit mutant p53 to chromatin I performed chromatin immunoprecipitation sequencing studies in the presence or absence of different ETS factors to determine differences in mutant p53 binding. For these studies I knocked down ETS2 or ERG prior to performing p53 ChIP-Seq to determine differences in p53 binding to chromatin under these conditions. My analyses of these data indicate that each of the conditions resulted in different p53 binding patterns in the ChIP-Seq and that there is a requirement for ETS in mutant p53 binding.My studies have demonstrated that ETS proteins interact with mutant p53 and that this interaction seems to be required for mutant p53 binding to the genome. My future work will test phenotypes related to ETS/mutant p53 interactions. Ultimately, if ETS/mutant p53 interactions are deemed important for oncogenic function, these will be attractive targets for future drug development.
Citation Format: Stephanie Metcalf, Stevie Morris, Peter Hollenhorst. Mechanisms of mutant p53 targeting to the genome [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2365.
Abstract 237: Evaluation of cell membrane lipid-extracted nanoliposomes (CLENs) as a potential drug platform for targeting multiple myeloma
Authors: Tran Christina T. , Park Eden , Rodriguez-Flores Pedro L. , Campbell Robert B. 
Published: June 2022

Abstract
Background: Multiple myeloma (MM) is a plasma cell malignancy that primarily affects the elderly. MM is the second most common hematologic cancer with approximately 25,000-30,000 new cases diagnosed annually in the United States. A challenge associated with MM therapy is unwanted drug uptake by normal healthy cells. Nanoparticles provide a promising outlook to mitigate these issues, offering more selective drug uptake, while minimizing toxicity associated with treatment. The objective of this study was to develop, optimize and evaluate physicochemical and In vitro properties of MM-CLENs in comparison to conventional liposomes and relevant cell controls.
Methods: RPMI-8226 MM cell line was selected cellular model for MM disease. RPMI-8226 cells were cultured and expanded In vitro for cellular extraction purposes. Lipid extraction (LE) procedures were performed to generate the RPMI-8226 LE ingredient. Other lipid ingredients used in preparation of RPMI-8226 CLENs included DOPC, cholesterol, and DPPE-Rhodamine (fluorescence indicator). Phase I included physicochemical characterization and cellular uptake studies of CLENs preparations with varying concentration of RPMI-8226-LE (0 to 40 mol%) content. Phase II began with the optimized concentration of LE determined in Phase I, along with varying concentrations of cholesterol (0 to 40 mol %) content for the nano-targeting studies in vitro. The control cell lines represent other hematological diseases, K-562-GFP (chronic myeloid leukemia), CCRF-CEM (acute lymphoblastic leukemia), and U937 (lymphoma).
Results: Phase I and II physicochemical characterization and In vitro studies, revealed that the optimized preparation of RPMI-8226-CLENs consisted of 5% LE, and 5% cholesterol content. Optimal preparation consisted of DOPC: Cholesterol: LE (90:5:5) with an average values for particle size and zeta potential of 178±38 nm (n=4), and -14±4 mV (n=4), respectively. The inclusion of LE in conventional DOPC:cholesterol liposomes resulted in significantly improved uptake of the CLENs by RPMI-8226 cells in vitro (P&lt; 0.001). However, preliminary selectivity studies suggest no significant difference in the uptake of RPMI-8226-CLENs by RPMI-8226 when compared to control cells (K-562-GFP, CCRF-CEM and U937).
Conclusion: Studies involving RPMI-8226 CLENs are currently underway. Such studies include target selectivity, and influence of additional components of CLENs as a function of the microenvironment.
Citation Format: Christina T. Tran, Eden Park, Pedro L. Rodriguez-Flores, Robert B. Campbell. Evaluation of cell membrane lipid-extracted nanoliposomes (CLENs) as a potential drug platform for targeting multiple myeloma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 237.
Abstract 2377: Impairment of p53-activating pathways accelerates liver cancer initiation partially through MTHFD1L-mediated 1C metabolism
Authors: Zhang Yiwei , Zha Yitian , Lu Hua 
Published: June 2022

Abstract
Hepatocellular carcinoma (HCC) takes several decades to develop from premalignant lesions in chronically damaged livers and is often detected at a later stage; thus, prevention is of particular importance. HCC originates from differentiated hepatocytes. Previous studies have shown that inhibition of the tumor suppressor p53 is required for the differentiated hepatocytes to acquire the features that are needed for their conversion to HCC progenitor cells (HcPCs). However, the initiation of p53 response to de-differentiation of damaged hepatocytes is largely unclear. p53 is tightly controlled by MDM2 and MDMX. We and others have previously demonstrated that multiple stresses can trigger the binding of 14-3-3 to phosphorylated MDMX, or ribosomal proteins L5 and L11 to MDM2, to further disrupt the MDMX- or MDM2-p53 association and lead to p53 activation. This was validated by two animal models, MDM2C305F and MDMX3SA knock-in mice that are defective in 14-3-3-MDMX and L5/L11-MDM2 interactions, respectively. By crossing these two mouse lines, we generated a double knock-in (DKI) mouse line. With this line, we found that carcinogen DEN-induced HCC occurrence is significantly higher in MDM2C305F-MDMX3SA -DKI mice, and HcPCs isolated from DEN-treated DKI mice display significantly more stem cell- and malignancy- properties and higher tumorigenesis when introduced into mouse livers. Furthermore, we found that MTHFD1L, a monofunctional tetrahydrofolate synthase required for mitochondrial 1-carbon (1C) metabolism, is transcriptionally suppressed by p53 and exerts a critical effect on the accelerated HCC initiation in DKI mice. Taken together, these results demonstrate a crucial role of these two p53-activating pathways in preventing HCC initiation by controlling the mitochondrial 1C- metabolism.
Citation Format: Yiwei Zhang, Yitian Zha, Hua Lu. Impairment of p53-activating pathways accelerates liver cancer initiation partially through MTHFD1L-mediated 1C metabolism [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2377.
Abstract 2386: Investigating cyclopamine tartrate as a potential suppressor of lung adenocarcinoma and squamous cell carcinoma
Authors: Berisha Eranda , Ashrafi Adnin , Castro Maria Del Carmen Chacon , Zhang Li 
Published: June 2022

Abstract
Lung cancer is the leading cause of death by cancer, and non-small cell lung cancer comprises of 85-90% of lung cancer cases. Previous studies have demonstrated the importance of heme in mitochondrial metabolism and OXPHOS. Heme is an essential molecule in the oxidative phosphorylation pathway especially since Complex II-IV all contain heme. During lung tumorigenesis there is a marked increase in heme synthesis and uptake; other protein and enzymes relating to heme were also upregulated. Heme-sequestration proteins (HeSPs) have shown high effectiveness in suppressing the development and progression of lung adenocarcinoma and squamous cell carcinoma, therefore targeting heme using CycT should yield similar results. Previous studies have indicated that cyclopamine tartrate (CycT) can effectively arrest lung tumor growth and progression. CycT does this by inhibiting the levels of proteins and enzymes involved in heme uptake, synthesis, as well as reducing heme synthesis and degradation in adenocarcinoma. We therefore aim to examine the effectiveness of CycT in both, adenocarcinoma and squamous cell carcinoma.In vitro experiments using NSCLC adenocarcinoma cell line A549 and squamous cell carcinoma HCC15 are in progression with initial results supporting the hypothesis. Cell proliferation assays have shown a marked decrease in CycT-treated groups in both cell lines. Based on colony formation assays, results indicate that CycT inhibits colony formation. Heme synthesis and degradation have also shown the effectiveness of CycT in suppressing tumorigenesis in both cell types. Oxygen consumption rates of both cell types were examined with CycT inhibiting oxygen consumption. Overall, in vitro experiments support the idea that CycT can suppress or arrest lung adenocarcinoma and squamous cell carcinoma.
Citation Format: Eranda Berisha, Adnin Ashrafi, Maria Del Carmen Chacon Castro, Li Zhang. Investigating cyclopamine tartrate as a potential suppressor of lung adenocarcinoma and squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2386.
Abstract 2394: Discovery of a sex-specific metabolic phenotype in KRAS mutant colorectal cancer
Authors: Yan Hong , Cai Yuping , Shen Xinyi , Jain Abhishek , Paty Philip B , Bosenberg Marcus , Khan Sajid A , Johnson Caroline 
Published: June 2022

Abstract
KRAS mutations occur in 35-45% of all colorectal cancer (CRC) cases and are notoriously difficult to treat. It is known that anomalous metabolism is a hallmark for cancer, however the relationship between mutant KRAS and tumor metabolism in CRCs has not been fully explored. We recently showed sex-disparities in metabolism by primary tumor location, indicating the pressing need to investigate the role of biological sex in CRC. Our aim was therefore to determine whether mutant KRAS alters metabolism in a sex-specific manner. We performed non-targeted metabolomics and targeted metabolomics on stage I-III chemotherapy-naive KRAS-mutant and wild type CRC patient tumor tissues (n=197) using ultra-high-performance liquid chromatography (UHPLC) coupled to quadrupole Time-of-Flight Mass Spectrometry (QTOF-MS), and tandem MS (MS/MS). Our results showed that tumors from male patients were cystine(cysteine)-dependent, with altered glutathione (GSH) biosynthesis, transsulfuration activity, methionine metabolism, utilization of lipoxygenase pathways. Simultaneously, we performed comprehensive bioinformatic analysis of gene expression data from the Gene Expression Omnibus to further validate mutant KRAS effects on CRCs by sex. Our findings demonstrated differential expression to CBS, GPX4, GSS, ACSL4, ATF4, FTH1 and EGPR genes that are all involved in regulation of these metabolic pathways and indicate a role for ferroptosis. This data therefore validated our findings of decreased transsulfuration activity (regulated by CBS) and decreased GSH biosynthesis (regulated by GSS) in male patients; this finding was not seen in female patients. To further examine differences in ferroptosis by sex, it was seen that GPX4 was differentially expressed between KRAS mutant and wild type (p&lt;0.05) in males, but not in females. Meanwhile, ACSL4, which appears to be a predictive marker for ferroptosis sensitivity, showed upregulated expression in males with mutant KRAS (p&lt;0.00001). Further, KRAS mutant type linked to a poor 5-year overall survival only in male using Kaplan-Meier survival analysis. This is the first report to show unique sex-specific metabolic signatures by KRAS status in CRC patients indicating a role of decreased ferroptosis in males, thus a novel avenue for therapeutic approaches.
Citation Format: Hong Yan, Yuping Cai, Xinyi Shen, Abhishek Jain, Philip B Paty, Marcus Bosenberg, Sajid A Khan, Caroline Johnson. Discovery of a sex-specific metabolic phenotype in KRAS mutant colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2394.
Abstract 2403: Regulation of FAK phosphorylation by serine/threonine protein phosphatases in cancer cells
Authors: Li Lin , Liu Lie , Huang Shile 
Published: June 2022

Abstract
Focal adhesion kinase (FAK), a non-receptor tyrosine kinase, is activated by growth factors and integrin clustering, promoting cell migration, a critical step for cancer metastasis. The activity of FAK is closely associated with the phosphorylation of diverse residues, which are mediated by various protein tyrosine kinases and phosphatases. Previous studies have demonstrated that serine/threonine protein phosphatase 5 (PP5) promotes cell migration, while protein phosphatase 2A (PP2A) inhibits cell migration. However, whether PP5 and PP2A regulate cell migration by mediating FAK phosphorylation is poorly understood. In this study, we found that overexpression of PP5 decreased FAK phosphorylation at S722, and knockdown of PP5 increased p-FAK (S722) in a spectrum of tumor cell lines. Our co-immunoprecipitation (co-IP) results showed an interaction between PP5 and FAK. In addition, we observed that overexpression of PP5 induced S178 phosphorylation of paxillin, an FAK interacting protein. However, there was no physical interaction between PP5 and paxillin, indicating an indirect regulation. In addition, knockdown of PP2A enhanced the phosphorylation of FAK and conferred resistance to rapamycin inhibition of IGF-I-stimulated phosphorylation of FAK. To our surprise, by co-IP, we failed to detect any direct interaction between FAK and PP2A. Further research will determine how PP5 and PP2A regulate cell migration through FAK and paxillin.
Acknowledgements This work was supported by the Feist-Weiller Cancer Center (FWCC) Bridge Award (S.H.), Shreveport, LA, USA
Citation Format: Lin Li, Lie Liu, Shile Huang. Regulation of FAK phosphorylation by serine/threonine protein phosphatases in cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2403.
Abstract 2412: Emergence of resistance to MTI-101 selects for favorable MET phenotype in lung cancer
Authors: Jones Clark , Hazlehurst Lori 
Published: June 2022

Abstract
Lung cancer remains the most-deadly of all cancers, and thus clinical evidence indicates novel treatment strategies are needed to improve patient outcomes. Our laboratory has been developing a novel cyclic peptide coined MTI-101, which induces cell death via calcium overload, a finding dependent on the TRPC1/TRPC5/TRPC4 complex. To better understand determinants of sensitivity and resistance to MTI-101, we developed drug resistant isogenic lung cancer cell lines. Two isogenic drug resistant cell lines were generated with chronic exposure to MTI-101 in PC-9 (NSCLC EGFR Driven) and H446 (SCLC PTEN Deleted and c-MYC amplified). Drug resistance was confirmed in both cell lines with over two-fold increases in IC50 values upon treatment with MTI-101 in MTT assays. Interestingly, pushing the resistant levels beyond a two-fold increase was not obtained as cultures did not sustain growth with increased selection pressure. Using the isogenic systems coupled with RNA-SEQ, the top enriched GSEA hallmark was downregulation of genes that contribute to EMT in both MTI-101 resistant lines. The RNA-SEQ data correlated with changes in the phenotype which included a significant decreased invasion in Matrigel and changes of MET markers (E-Cadherin, Vimentin) at the protein level. Furthermore, in the EGFR driven PC-9 cell line, selection for resistance towards MTI-101 resulted in collateral sensitivity to EGFR inhibitors. To determine the stability of the MET phenotype, cells were removed from drug, then tested for invasion and drug resistance every month. Our data indicated that the MET phenotype and genotype was stable for a minimum of six months. RNA-SEQ data continued to demonstrate decreased expression of EMT in cells removed from drug compared to the parental cell line. MTI-101 treatment in PC-9 and H446 cells showed synergistic activity with standard of cares Erlotinib, Osimertinib, and Cisplatin when used in combination on the wildtype cells as well. Finally, in vivo data indicates that MTI-101 treatment selects for increased E-Cadherin and decreased Vimentin. Similar to the cell line model, this finding correlated with decreased incidence of bone metastasis in the PC-9 in vivo model. Together our data indicate that MTI-101 treatment could be used as a tool to delay the emergence of resistance and potentially inhibit or delay the emergence of metastatic disease for the treatment of lung cancer.
Citation Format: Clark Jones, Lori Hazlehurst. Emergence of resistance to MTI-101 selects for favorable MET phenotype in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2412.