bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5671: Thermotherapy interferes with XRCC1/PARP1-mediated DNA repair and confers sensitization of ovarian cancer to oxaliplatin
Authors: Shen Fangrong
Published: June 2022

At present, hyperthermia combined with chemotherapy has become a clinical treatment means Despite some research reports investigating the effects of heat elevation on inducing the DNA damage response and interfering with various DNA repair pathways, but the underlying coalition mechanisms of combined with PARP inhibitorss are not yet completely elucidated. In this study, We use a variety of OC cell lines treat by thermo-chemotherapy and then the proliferation, colony formation ability, apoptosis, and cell cycle distribution of OC cells were measured. Here, We found that in heat sensitive cell line A2780cells treat by thermo-chemotherapy combined wint PARPi, could induces Ppromote OC cells apoptosis and inhibit proliferation, aggravate DNA damage and arrests OC in the cell cycle S phase, buthowever, in heat resistance cell line SKOV3 cells there exhibited an Constant tendency. Western blot analysis shows hyperthermia down-regulated the levels of PARP1 and XRCC1.In addition, hyperthermia combined with chemotherapy could increase the expressions of ATM and NBS1 in the double-stranded DNA damage pathway. Meanwhile, The expression of DNA damage-related proteins increased after PARP1 inhibitors eliminated single-strand repair. Based on these results, we conclude hyperthermia confers sensitization of ovarian cancer to oxaliplatin via interference with XRCC1/PARP1-mediated base excision repair be consumed and Promotes DNA double strand breakage, thereby inhibiting OC development.

Citation Format: Fangrong Shen. Thermotherapy interferes with XRCC1/PARP1-mediated DNA repair and confers sensitization of ovarian cancer to oxaliplatin [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 5671.
Abstract 5686: Integrative genomic analysis reveals hypermethylation triggered GPER1 loss is associated with genomic instability of endometrial cancer
Authors: Feng Xuan , Huang Ting , Shen Boqiang , Hao Juan , Wang Jiaqi , Dong Yangyang , Zhou Jingyi , Wang Jianliu
Published: June 2022

Objective: Endometrial cancer is a common gynecologic malignancy, yet carcinogenesis remains elusive. Evidence showed that aberrant genomic methylation profiling contributes to the development of endometrial cancer. G protein-coupled estrogen receptor (GPER1), a membrane-associated estrogen receptor, was reported to play a multifaceted role in tumors. Its function in endometrial cancer is little known. Here, we conducted an integrated analysis of RNA expression, DNA methylation, and somatic mutations data from TCGA to investigate GPER1 upstream regulator and its influence in endometrial cancer biological process.

Methods: RNA-seq, DNA methylation, and clinical information of endometrial cancer (n=554) and normal control (n=33) were obtained from TCGA database. RNA-seq profiles of GPER1 low and high groups were analyzed by R 4.1.0 software. KEGG and GSEA based on GPER1 expression were conducted. Correlation analysis of GPER1 and genomic instability were displayed. G1, the GPER1 agonist, was added to observe cell viability and metastatic ability in vitro. DNA methylation data was analyzed.

Results: GPER1 expression was decreased in endometrial cancer compared with normal tissues. GPER1 was associated with poor overall survival (HR=0.52, p=0.003) (Figure 1). Low expression group showed a more frequent mutation landscape, higher tumor mutation burden (TMB), and micro-satellite instability (MSI) (Figure 2). Several hypermethylation loci on GPER1 CpG island were revealed. Methylation status is negatively correlative to RNA expression of GPER1 (Figure 3). P-value <0.05 and log2FC >1.5, 473 up-regulated and 114 down-regulated genes were screened. Up-regulated DEGs enriched in the Estrogen signaling pathway, Endometrial cancer, wnt signaling pathway, etc. Down-regulated DEGs enriched in Cell cycle, p53 signaling pathway, etc. (Figure 4). GSEA analysis showed that GPER1 low expression group was enriched in several biological processes including cell cycle checkpoint, Recombinational repair, etc. G1 inhibited endometrial cancer cell growth in a dose-dependent manner, and reduced cell metastatic ability (Figure 5).

Conclusions: GPER1 exhibited decreased expression in endometrial cancer and DNA hypermethylation in promoter CpG island locus. The low GPER1 expression group showed prominent genomic instability. GPER1 agonists inhibit endometrial cancer cell growth and metastasis, which may serve as a therapeutic target.

Citation Format: Xuan Feng, Ting Huang, Boqiang Shen, Juan Hao, Jiaqi Wang, Yangyang Dong, Jingyi Zhou, Jianliu Wang. Integrative genomic analysis reveals hypermethylation triggered GPER1 loss is associated with genomic instability of endometrial 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 5686.
Abstract 5698: Genome-wide DNA methylation profiling for differentiating synchronous endometrial and ovarian cancer
Authors: Chan Yusanne Yung Sing , Wong Oscar Gee Wan , Cheung Annie Nga Yin
Published: June 2022

Background: Synchronous endometrial and ovarian cancer (SEOC) refers to simultaneously discovered endometrial and ovarian tumours on the same patient. SEOC may represent double primary (DP) tumours that arise independently on the two sites, or clonally related (CR) tumours that arise either on the endometrium or ovary and metastasized to the other site. Accurate differential diagnosis between these two scenarios can implicate on the treatment options and prognostication of SEOC. However, it is difficult to achieve as the histopathological features of DP and CR tumours are often ambiguous. DNA methylation landscape of SEOC may provide markers for differentiating DP and CR tumours but remain largely unexplored.

Methods: The archival tissues of six pairs of SEOC and their accompanied normal uterine tissues were retrieved. The tumours were accessed by conventional histopathological criteria and mitochondrial DNA (mtDNA) sequencing to categorize them into DP or CR. We then analyzed the methylation profiles of >850,000 CpG sites of the tumor samples using the Illumina Infinium MethylationEPIC BeadChip array. Downstream methylation analysis was performed in the R/Bioconductor package ChAMP. Gene ontology (GO) enrichment analysis on the methylation driven genes was done using PANTHER.

Results: mtDNA sequencing revealed that among the 6 cases of SEOC, there are 3 DP and 3 CR. Clustering analysis of differentially methylated CpGs (DMPs) between tumours of the same tissue type effectively distinguished endometrial and ovarian tumours into DP or CR. Thus, DP and CR endometrial tumour showed 50 DMPs and 15 differentially methylated regions (DMRs), but no significantly enriched signaling pathway was identified. On the other hand, there were 1,105 DMPs and 44 DMRs that mapped to 601 known genes between DP and CR ovarian tumours. GO analysis revealed that the hypomethylated genes in CR ovarian tumour were enriched in several metastatic-related processes, including cellular response to stimulus, regulation of cell projection organisation, cell migration and negative regulation of voltage-gated potassium channel activity.

Conclusions: Taken together, our findings demonstrated that DNA methylation profiling can be used for SEOC patient stratification and may enhance our understanding of epigenetic regulation of SEOC pathogenesis.

Citation Format: Yusanne Yung Sing Chan, Oscar Gee Wan Wong, Annie Nga Yin Cheung. Genome-wide DNA methylation profiling for differentiating synchronous endometrial and ovarian 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 5698.
Abstract 5704: IDH2 mutation reduce radiotherapy induced immune response in glioblastoma by affecting micronucleus formation
Authors: Elkashef Sara Mahmoud , Nicholson Shirony , Harding Shane
Published: June 2022

DNA methylation is the most abundant epigenetic modification, it plays a critical role in tissue homeostasis, genomic stability, and mitotic fidelity. Isocitrate dehydrogenase genes (IDH1/2) are non-redundantly mutated in several types of cancers including Glioblastoma (GBM), and their mutation induces a DNA hypermethylation phenotype. Radiotherapy (RT), either alone or in combination with other treatments, forms a primary intervention for GBM but the full scope of how IDH1/2 mutations influence this response are not known. In this work, we demonstrate that IDH2 mutation reduces the formation of post-RT micronuclei (MN), small DNA bodies in the cytoplasm distinct from the primary nucleus. Previously, MN has been found to recruit the pattern recognition receptor cGAS to activate an interferon-mediated signalling cascade via STING. We demonstrate that hypermethylation induced by IDH2 mutation does not impact cGAS localization to MN but instead reduces the overall burden of MN which correlates with decreased cGAS-STING mediated transcriptional activation. Mechanistically, IDH2 mutation drives centromeric hypermethylation which stabilizes kinetochore assembly and the fidelity of mitotic chromosome segregation post radiation. We also demonstrate that a reduction of MN formation in IDH2 mutant tumors reduces synergy between RT and immune checkpoint blockade in murine glioma models. Together our data suggest that metabolic alterations in cancers directly influence mitotic fidelity and response to RT with important implications for combination treatments that capitalize on synergy with the innate cellular signalling toward the adaptive immune system.

Citation Format: Sara Mahmoud Elkashef, Shirony Nicholson, Shane Harding. IDH2 mutation reduce radiotherapy induced immune response in glioblastoma by affecting micronucleus formation [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 5704.
Abstract 5729: Dynamic phase separation of the androgen receptor and its coactivators to regulate gene expression
Authors: Zhang Fan , Biswas Maitree , Lee Joseph , Lingadahalli Shreyas , Wong Samantha , Wells Christopher , Saxena Neetu , Sun Bei , Parra-Nuñez Ana K. , Sanchez Christophe , Foo Jane , Chan Novia , Ung Lauren , Khan Nabeel , Altıntaş Umut Berkay , Bui Jennifer M. , Wang Yuzhuo , Fazli Ladan , Rennie Paul S. , Lack Nathan , Cherkasov Artem , Gleave Martin E. , Gsponer Joerg , Lallous Nada
Published: June 2022

Numerous cancers, including prostate cancer (PCa), have been shown to be addicted to transcription programs driven by specific genomic sites known as superenhancers (SEs). Recently, it has been proposed that the robust transcription of genes at such SEs is enabled by the formation of phase-separated condensates by transcription factors and coactivators with intrinsically disordered regions. The androgen receptor (AR), the main oncogenic driver in PCa, contains large disordered regions and is co-recruited with the transcriptional coactivator MED1 to SEs in androgen-dependent prostate cancer cells, thereby promoting oncogenic transcriptional programs. In this work, we show that AR-rich, liquid-like foci form in prostate cancer models upon androgen stimulation. We reveal that foci formation correlates with AR transcriptional activity, which can be modulated by changing cellular foci content genetically or chemically. We also demonstrate that the transcriptional coactivator MED1 plays an essential role in the formation of transcriptionally active AR-rich foci and that AR antagonists that block cofactor recruitment or DNA binding hinder foci formation and thus AR transcriptional activity. The liquid like properties of the condensates were also validated in-vitro by using recombinant AR protein. Using clinical specimens, we detected the interaction between AR and MED1 in advanced forms of prostate cancer and not in benign tissues. These results suggest that enhanced compartmentalization of AR and coactivators at SEs may play an important role in the activation of oncogenic transcription programs in androgen-dependent PCa. A better understanding of the assembly and the regulation of these AR-rich compartments may provide novel therapeutic options for PCa by targeting downstream events of androgen activation and DNA binding of AR.

Citation Format: Fan Zhang, Maitree Biswas, Joseph Lee, Shreyas Lingadahalli, Samantha Wong, Christopher Wells, Neetu Saxena, Bei Sun, Ana K. Parra-Nuñez, Christophe Sanchez, Jane Foo, Novia Chan, Lauren Ung, Nabeel Khan, Umut Berkay Altıntaş, Jennifer M. Bui, Yuzhuo Wang, Ladan Fazli, Paul S. Rennie, Nathan Lack, Artem Cherkasov, Martin E. Gleave, Joerg Gsponer, Nada Lallous. Dynamic phase separation of the androgen receptor and its coactivators to regulate gene expression [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 5729.
Abstract 5746: Analysis of molecular characteristics of gliomas harboring gene fusions
Authors: Wang Jidong , Han Yushuai , Wang Weiran , Ma Tonghui
Published: June 2022

Background: Genotyping plays an important role in tumor diagnosis and prognosis. The 2016 central nervous system (CNS) WHO added molecular parameters to classify CNS tumors on the basis of routine histological features, but the characteristics of gene fusion variations have not been clarified in CNS tumors.

Methods: In order to identify the characteristics of gene fusions in Chinese patients with CNS malignant tumors, we retrospectively analyzed the next-generation sequencing data of 234 patients (pts) with gene fusions.

Results: According to WHO classification of CNS tumor, 121 pts (51.7%) were low-grade gliomas (LGG, grade I, II), and 113 pts (48.3%) were high-grade gliomas (HGG, grade III, IV). The age of pts with LGG (14.1 ± 16.1) was significantly lower than HGG pts (50.2 ± 17.4) (P<0.0001). There was no significant gender difference between them (P = 0.161). In the fusion map of pts with LGG, gene fusions of KIAA1549-BRAF (n=82, 67.7%) and FGFR3-TACC3 (n=7, 5.8%) occurred frequently. Meanwhile, there were 5.7% pts carrying BRAF fusions with other partners, and some other sporadic fusions. Among HGG cases, the most frequent gene fusion was FGFR3-TACC3 (n=36, 31.9%), followed by fusions in EGFR (n=22, 19.5%), MET (n=16, 14.2%), BRAF (n=8, 7.1%), ROS1 (n=5, 4.4%), and other sporadic genes. It can be seen that gene fusion characteristics varied from gliomas with different malignant degrees. KIAA1549-BRAF fusion tended to occur in LGG (67.7% vs. 2.7%, P < 0.0001) than HGG, and FGFR3-TACC3 tended to occur in HGG ( 31.9% vs. 5.8%, P< 0.0001) than LGG. In addition, FGFR3-TACC3 fusion pts were exclusive with IDH1/2 mutations, but tended to be co-mutate with TERT promoter variants (P<0.0001). IDH-mutation-positive glioma usually exhibit a better clinical result, while TERT promoter-mutated glioma predicts a poor outcome. We also found that 75% (12/16) of MET fusion-positive gliomas pts had TP53 co-coexisting and 56.3% (9/16) of MET fusion-positive gliomas pts co-occurred with MET amplification, while only 0.9% (1/105) of pts harboring other fusions were MET amplification positive. Meanwhile, 95.0% (21/22) of EGFR fusion-positive pts co-occurred with EGFR amplification.

Conclusion: By comprehensively analyzing the gene fusion map of Chinese patients with gliomas, we found the gene fusion characteristics of LGG differed from that of HGG. These fusion features may be important molecular information for judging the grade of malignancy and prognosis of patients.

Citation Format: Jidong Wang, Yushuai Han, Weiran Wang, Tonghui Ma. Analysis of molecular characteristics of gliomas harboring gene fusions [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 5746.
Abstract 5757: Germline and somatic mutational landscape of Chinese early-onset colorectal cancers
Authors: Zeng Xiancheng , Liu Junhao , Luo Yurong , Li Hailiang , Liu Xinyi , Huang Mengli
Published: June 2022

Background: The incidence of colorectal cancer (CRC) in young people, described as early-onset colorectal cancer (EOCRC) has been rising up in decades. Apart from definite familial genetic disease, a considerable proportion of EOCRC remained unknown of the mechanism. Characterizing the difference in genomic features of EOCRC and late-onset CRC (LOCRC) would help us to understand it.

Methods: A total of 1777 Chinese CRC patients diagnosed in 2019-2020 were included. 489 patients under 50 years were defined as EOCRC. A 733-gene panel next-generation sequencing (NGS) testing and measurement of tumor mutational burden (TMB) levels based on the panel were conducted in all patients’ tumor specimen. Lynch syndrome (LS) was defined as patients harboring at least one non-benign germline mutation in four LS MMR genes (MLH1, MSH2, MSH6, PMS2).

Results: 43 of 489(8.8%) cases and 54 of 1288 (4.2%) cases were MSI-H in EOCRC and LOCRC, separately. Excluded 97 LS patients (84.3% in MSI-H EOCRC and 72.0% in MSI-H LOCRC), the proportion of non-LS MSI-H in EOCRC and in LOCRC were 1.8% and 1.7%, separately. Compared to non-LS MSI-H LOCRC, EOCRC has higher germline mutational frequencies in APC, CD74, ATM, BCL2L11, CHEK2, and RECQL4 genes and somatic mutational frequencies in APC, ERCC4, CHD2, ARHGAP5, CASP8, and ATM genes. In non-LS MSS patients, germline mutations in CHEK2, NBN and POLE genes, somatic SNV/indels in RNF43, ATR, AFF3, JAK2, POLG, CHD2 genes and somatic copy number gain in genes on chromosome 8 (ZNF703, FGFR1, MYC, PTK2) occurred more frequently in EOCRC. KEGG enrichment analysis in somatic mutations indicated significant overexpressed MAPK signaling pathway. The TMB level was significantly lower in non-LS MSS EOCRC than in LOCRC.

Conclusions: The proportion of non-LS MSI-H in Chinese EOCRC and LOCRC were approximate. Non-LS MSS EOCRC had marked chromosome 8 somatic copy number gain and MAPK signaling pathway, indicating the potential mechanism. The comparative lower TMB level in EOCRC was concordance with previous studies and the correlations between low TMB level and high CNV burden also corroborate the etiopathogenesis.

Citation Format: Xiancheng Zeng, Junhao Liu, Yurong Luo, Hailiang Li, Xinyi Liu, Mengli Huang. Germline and somatic mutational landscape of Chinese early-onset colorectal cancers [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 5757.
Abstract 5776: Predictors of radioactive iodine refractoriness in papillary thyroid carcinomas
Authors: Masoodi Tariq , Siraj Sarah , Siraj Abdul K. , Azam Saud , Qadri Zeeshan , Parvathareddy Sandeep K. , Al-Kuraya Khawla S.
Published: June 2022

Optimized surgery and radioactive iodine (131I, RAI) are the cornerstone of treatment for papillary thyroid carcinoma (PTC). Although standard treatment is curative for most, 5-20% of PTC patients develop RAI refractory disease – the main cause of thyroid cancer-related deaths. Early predictors indicating therapeutic response to RAI therapy in PTC are yet to be elucidated. We performed whole-exome sequencing (at a median depth of 198x) on 158 patient-matched primary PTCs and germline DNA. Clinical data was used to categorize RAI avidity in the PTC cohort. Whereby, 66 RAI refractory and 92 RAI avid tumors were identified. Clinical data and somatic variants were analyzed to compare the clinicopathological presentation, genomic landscape and mutational signatures between RAI refractory and avid PTCs. RAI refractory tumors were significantly associated with distinct aggressive clinicopathological features, including positive surgical margins (65.5% versus 26.7%; p=0.016) and the presence of lymph node metastases at primary diagnosis (62.5% versus 30.1%; p=0.012); higher nonsilent tumor mutation burden (p=0.011); and the enrichment of APOBEC-related single base substitution (SBS) COSMIC mutational signatures 2 (p=0.03) and 13 (p<0.001). APOBEC mutational signatures were not associated with BRAFV600E mutation. Notably, using multivariate logistic regression analysis only the SBS13 (odds ratio 13.01, 95% confidence intervals 1.20-140.94) APOBEC mutational signature was revealed to be an independent predictor of RAI refractoriness in PTC (p=0.035). Furthermore, using Cox proportional hazards SBS13-positive tumors (hazard ratio 3.52, 95% confidence intervals 1.79-6.91) were also significantly associated with poorer progression-free survival (p<0.001), albeit only in univariate analysis. This study highlights distinct clinical and genomic features in RAI refractory PTC, but above all proposes the APOBEC SBS13 mutational signature as an independent predictor of RAI refractoriness in a more aggressive subgroup of PTC. Where detection of RAI refractory disease following standard surgical PTC removal, and more suitable therapeutic interventions may potentially improve patient outcomes.

Citation Format: Tariq Masoodi, Sarah Siraj, Abdul K. Siraj, Saud Azam, Zeeshan Qadri, Sandeep K. Parvathareddy, Khawla S. Al-Kuraya. Predictors of radioactive iodine refractoriness in papillary thyroid carcinomas [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 5776.
Abstract 5782: Sample management for enabling successful single-cell RNAseq processing
Authors: Halvorsen Priya J. , Britton Caitlin W. , Shaban Hiba , Torres Fernando , Wilson Douglas , Modarelli Joseph
Published: June 2022

Background: Single cell analysis allows the profiling of biomolecules on a cell-by-cell basis, revealing insights into how cellular heterogeneity impacts biological mechanisms. Drug discovery and development have greatly benefited from the comparative, longitudinal, and causal information single cell analysis provides, transforming our ability to understand disease. Many preclinical and clinical studies leveraging single cell resolution have already played a crucial role in target identification and biomarker discovery. From collection through analysis, proper sample management is a crucial and challenging aspect of large-scale clinical research studies and directly influences specimen quality and the ability to interrogate specific cell populations of interest.

Methods: We sought to determine the effect of collection and storage conditions for PBMCs enriched from whole blood prior to downstream processing using our scRNAseq workflow. PBMCs were freshly isolated from whole blood collected in EDTA tubes or following storage at various timepoints and temperatures until PBMC isolation. Samples were then cryopreserved after the conclusion of each isolation stage and later processed to assess impact of cryopreservation. All PBMC samples were processed using the Chromium Single Cell Immune Profiling kit to compare gene expression and immune repertoire profiling across all storage conditions.

Results: We found that gene expression data were highly correlated across all storage conditions tested. We also found that the clustering and annotation of PBMC libraries were comparable across all conditions tested, but certain subsets were more sensitive to these conditions, indicated by an elevation in cell stress and apoptosis markers.

Conclusions: When planning future studies, it is imperative to consider collection and storage conditions in the workflow of processing for enabling high quality samples for single cell analysis, especially with regard to sensitive and rare cell types of interest.

Citation Format: Priya J. Halvorsen, Caitlin W. Britton, Hiba Shaban, Fernando Torres, Douglas Wilson, Joseph Modarelli. Sample management for enabling successful single-cell RNAseq processing [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 5782.
Abstract 5821: Enhanced tumorigenesis in a novel miR-216a knockout/KPC mouse model of pancreatic cancer
Authors: Brock Andrew A. , Powell Katherine , Schmittgen Thomas D. , Sempere Lorenzo F.
Published: June 2022

Pancreatic ductal adenocarcinoma (PDAC) originates from both ductal and acinar cells of the pancreas. The highly abundant and acinar cell-enriched miR-216a is reduced during in vitro acinar ductal metaplasia (ADM), throughout PanIN progression, during the development of pancreatitis in mice and humans, and during development of mouse and human PDAC. To investigate the contribution of miR-216a in the development of PDAC, we generated a miR-216a germline knockout mouse (216aKO) via CRISPR genetic editing of a minimal and precise deletion of the miR-216a precursor sequence without affecting the host gene. We crossed this 216aKO mouse to the LSL-KrasG12D; LSL-Trp53Flox/+; Pdx1Cre/+ (KPC) mice to produce a transgenic mouse with an activating Kras mutation, p53 deletion, and knockout of miR-216a (referred to here as miR216aKPC). miR216aKPC displayed an increase in tumor progression compared to KPC and had reduced survival - median 15 weeks miR216aKPC vs. 25 weeks for KPC. miR216aKPC produced lung metastasis by 12 weeks of age which were not present in the lungs of similarly aged KPC mice. Transfection of miR-216a mimetic oligo into cell lines derived from KPC or 216aKPC mice did not reduce viability or alter cellular morphology, suggesting that a potential tumor suppressive role of miR-216a functions during the early stages of PDAC development. A three dimensional ADM assay using acinar cells derived from both mouse and human pancreata will be applied to investigate the contributions of miR-216a on the development of ADM and cell polarity. To discover miR-216a target genes that are responsible for the increased tumorigenesis, cell lines derived from miR216aKPC will be transfected with miR-216a mimetic or scrambled control oligo followed by RNA sequencing. Our results thus far suggest a tumor suppressive role for miR-216a in the early development of PDAC and future studies will investigate molecular and cellular mechanisms driving acinar cell-induced PDAC.

Citation Format: Andrew A. Brock, Katherine Powell, Thomas D. Schmittgen, Lorenzo F. Sempere. Enhanced tumorigenesis in a novel miR-216a knockout/KPC mouse model of pancreatic 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 5821.
Abstract 5824: Fully-humanized, bioengineered miR-1291 modulates key nutrient transport and metabolism to control tumor metabolism
Authors: Tu Mei-Juan , Gonzalez Frank J. , Yu Ai-Ming
Published: June 2022

Tumor progression is accompanied by metabolic reprogramming to allow carcinoma cells to access essential nutrients under the tumor microenvironment. To meet energetic and material needs for high-rate proliferation and tumorigenesis, cancer cells generally rely more heavily on vital nutrients (e.g., glucose, amino acids, and vitamins) than normal cells. Therefore, controlling nutrient transport and metabolism in cancer cells is a promising therapeutic strategy. Our previous studies have suggested that microRNA-1291-5p (miR-1291-5p or miR-1291) is downregulated in pancreatic cancer (PC) cells and acts as a tumor suppressor. The current study is to delineate the role of miR-1291 in the control of PC cell metabolism and develop miR-1291 therapy. We first employed our newly-invented RNA bioengineering technology to achieve high-level and large-scale, in vivo fermentation production of a fully-humanized biologic miR-1291 agent at a high degree of homogeneity (> 4 mg BioRNA per liter of culture and > 97% purity). RNA sequencing studies revealed that BioRNA/miR-1291 was selectively processed to target miR-1291-5p to modulate the transcriptome in PC cells. Proteomics study showed that a number of proteins were reduced remarkably in AsPC-1 cells by biologic miR-1291-5p, among which PNPO, an enzyme that mediates the synthesis of essential nutrient vitamin B6 (VB6), was revealed as a leading target of miR-1291-5p. Besides PNPO and the previously-reported glucose transporter SLC2A1/GLUT1, amino acid transporter SLC7A5/LAT1 was verified as a direct target for miR-1291-5p. Downregulation of PNPO, LAT1, GLUT1 protein expression by biological miR-1291 led to sharp alteration of homeostasis of glucose, amino acids, and VB6 in human PC cells, and subsequent suppression of glycolysis capacity and mitochondrial function as well as the increase of oxidative stress. Combination treatment with bioengineered miR-1291 and 5-FU exerted strong synergism in the inhibition of PC cell and organoid proliferation in vitro. In addition, miR-1291 mono- and combination therapy were effective to control tumor growth in pancreatic cancer patient-derived xenograft (PDX) mouse models. These results demonstrate a critical role for miR-1291 in the regulation of PC cell metabolism which provides insight in developing new therapeutic strategies for PC.

Citation Format: Mei-Juan Tu, Frank J. Gonzalez, Ai-Ming Yu. Fully-humanized, bioengineered miR-1291 modulates key nutrient transport and metabolism to control tumor 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 5824.
Abstract 5829: Characterizing cargoes of extracellular vesicles in promoting breast cancer growth and chemotherapy resistance
Authors: Ngue Harrison , Kim Hyejin , Vasudevan Shobha
Published: June 2022

Cancer cells employ bidirectional cell communication to maintain growth and metastasis in the tumor microenvironment. One mechanism of communication that has become increasingly appreciated is the secretion of extracellular vesicles (EVs), heterogeneous multi-signal messengers that support cancer dissemination through the transfer of biomolecules such as oncoproteins and noncoding RNA species. However, little is understood about EVs in relation to chemotherapy resistance. In this study, we profiled two different breast cancer cell lines: 1) BT549 (triple negative), treated with gemcitabine and paclitaxel chemotherapy, and 2) MCF7 (estrogen receptor-positive), treated with palbociclib and fulvestrant, compared to their wild-type states. EVs were collected from these cells using tangential flow filtration and quantified with Brownian motion-based nanoparticle tracking analysis and microfluidic resistive pulse sensing, and profiling of RNA and peptide markers was completed through RT-qPCR and Western blotting, respectively. Initial data showed that representative mitochondrial ribosomal genes mt12S and MRPS14 were among the most upregulated RNAs in our drug-exposed EV samples, indicating that extracellular transfer of mitochondrial materials plays a role in cancer growth under chemotherapy stress. These findings were supported by prior genetic research at the Vasudevan laboratory, in which a set of mitochondrial ribosomal RNAs was found to be upregulated in cytosine arabinoside-induced chemoresistant acute monocytic leukemia cells, as well as by the recent discovery of mitovesicles, a novel population of EVs that originate from mitochondria. Through additional efforts to isolate further subtypes of EVs, the mechanisms by which these mitochondrial cargoes promote chemoresistant phenotypes will be uncovered.

Citation Format: Harrison Ngue, Hyejin Kim, Shobha Vasudevan. Characterizing cargoes of extracellular vesicles in promoting breast cancer growth and chemotherapy resistance [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 5829.
Abstract 5843: Truncated APC & AXIN2 expression contribute to maintaining β-catenin/WNT signaling at the “Just Right” level for CRC cell proliferation
Authors: Zhang Chi , Facey Caroline O. , Funk Katherine , Opdenaker Lynn M. , Boman Bruce M.
Published: June 2022

Adenomatous polyposis coli (APC) mutation leads to increased WNT signaling and stem cell overpopulation, which drives development of colorectal cancer (CRC). APC mutations often encode a truncated protein that has loss of APC’s domains that mediate APC interaction with AXIN2. A substantial body of scientific evidence indicates that truncated APC is essential for CRC cell proliferation by maintaining beta-catenin levels and WNT signaling at the “just right” level (known as the “Just Right” Hypothesis). Thus, AXIN2 is of particular interest because both wild-type APC and AXIN2 are part of the beta-catenin destruction complex, which is essential for tumor-suppressing ability.

Hypothesis: the degree of AXIN2 expression, in the context of truncated APC, is critical to maintain WNT-signaling activity at the “just right” level which is optimal for CRC cell proliferation. Accordingly, we evaluated the effect of AXIN2 levels in CRC cells that contain APC protein-truncating mutations on WNT signaling (Top Flash assay), expression of WNT-targeted genes, and CRC cell proliferation and differentiation. We found that modulating AXIN2 expression altered WNT signaling, expression of WNT-targeted genes, and CRC cell proliferation in CRC cell lines with different APC-truncation causing mutations. Indeed, western blot results showed that knock down of AXIN2 gene expression increased truncated-APC and AXIN1 protein expression, and decreased expression of several WNT-target genes (e.g. LGR5, CD44, c-Jun, c-Myc, Cyclin D1), particularly genes that have reported roles in cell cycle regulation. These findings were consistent with our independent bioinformatics analyses of NCI TCGA RNA-seq data on CRC patients. Overall, our study suggests that i) The beta-catenin destruction complex is still functional at a certain level despite APC-truncating mutations; ii) Perturbing AXIN2 expression leads to changes in WNT-signaling activity that deviate from a level that is “just right” for malignant cell proliferation, likely by affecting the function of the destruction complex; iii) Deviation from “just right” WNT signaling levels alters WNT-target gene expression and diminishes the ability of APC-mutant CRC cells to maintain uncontrolled proliferation.

Citation Format: Chi Zhang, Caroline O. Facey, Katherine Funk, Lynn M. Opdenaker, Bruce M. Boman. Truncated APC & AXIN2 expression contribute to maintaining β-catenin/WNT signaling at the “Just Right” level for CRC cell proliferation [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 5843.
Abstract 5846: Comprehensive genomics-based screening of novel therapeutic targets and biomarkers for lung cancer
Authors: Daigo Yataro , Takano Atsushi , Nakamura Yusuke
Published: June 2022

As the number of patients with lung cancer who show good response to standard therapies is limited, new molecular targeted therapies and biotherapies with predictive biomarkers are urgently required. We have been developing molecular therapies targeting oncoproteins with their companion diagnostics as follows, i) To identify overexpressed genes in 120 lung cancers by gene expression microarray analysis of 27,648 genes, ii) To verify the candidate genes for their scarce expression in 23 normal organs, iii) To validate the clinicopathologic significance of their protein expression by tissue microarray covering hundreds of lung cancers including non-small cell lung cancers (NSCLCs), and iv) To examine whether they are important for the growth or invasion of cancer cells by using siRNAs and/or small molecule inhibitors. By this screening system, we identified dozens of candidate target molecules and selected a gene encoding protein with a GAP domain, LAPG1 (lung cancer-associated protein with Gap domain 1). Immunohistochemical analysis showed that LAPG1 expression was observed in 69.9% of lung cancers. Moreover positivity of LAPG1 expression was associated with poor prognosis for lung cancer patients. Knockdown of LAPG1 expression by siRNAs suppressed growth of lung cancer cells. Introduction of LAPG1 increased the invasive activity of mammalian cells, indicating that LAPG1 could be a prognostic biomarker and therapeutic target for lung cancers. Our comprehensive genomics-based screening might be useful to select the novel biomarkers and therapeutic targets for developing small molecules, antibodies, nucleic acid drugs, and immunotherapies against lung cancer.

Citation Format: Yataro Daigo, Atsushi Takano, Yusuke Nakamura. Comprehensive genomics-based screening of novel therapeutic targets and biomarkers for 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 5846.
Abstract 5854: Therapeutic targeting of p73-activated c-FLIP switches cell fate from growth arrest and survival to apoptosis in p53-deficient cancer cells
Authors: Zhang Shengliang , El-Deiry Wafik S.
Published: June 2022

The tumor suppressor p73, a member of the p53 family, transcriptionally activates numerous p53-target genes in cell cycle regulation and apoptosis. Therapeutic activation of p73 can restore p53-signaling in mutant p53-expressing cancer cells effectively bypassing the p53 deficiency. In addition to pro-apoptotic signaling, outcomes of p73 activation contain survival signals and this may provide insights in cell fate outcomes between cell survival and apoptosis after cellular stress. We report that cellular FLICE inhibitory protein (c-FLIP), a master antiapoptotic factor, is a novel transcriptional target of p73. To test if p73 regulates c-FLIP expression in p53-deficient cancer cells, we overexpressed p73 in p53-deficient cancer cells using p73-adenovirus. Overexpression of p73 dramatically increased c-FLIP at the protein and RNA levels. The effect of p73 on c-FLIP upregulation was blocked by knock-down of p73. ChIP assay showed that p73 binds to the c-FLIP promoter in a p73-level dependent manner. Furthermore, a luciferase reporter assay showed that p73 increased the c-FLIP-L-promoter-mediated luciferase reporter expression in p53-deficient cancer cells. To test the effect of the outcomes of p73 signaling on cell survival or death, we performed cell viability assay and found that p73 reduces cell viability in a p73-level dependent manner. We found an increase of both p21 and c-FLIP at the protein levels in response to overexpression of p73 in p53-deficient cancer cells, but no cleaved-PARP was detected and flow cytometric analysis showed the cells were arrested in G1 phase. These results suggest that p73 arrests the cell cycle and prevents apoptosis at the tested levels of p73. We knocked down c-FLIP using siRNA in p53-deficient cancer cells, and found that knockdown of c-FLIP enhanced cleaved-PARP, cleaved caspase- 3 and -8 correlated to high level of apoptotic signaling with Noxa and puma upregulation in response to the overexpression of p73. Our results suggest that the depletion of c-FLIP primes cellular apoptosis switching from p73-induced cell cycle arrest (cell survival) and sensitizes cells to p73-induced apoptotic signals in p53-deficient cells. The cell fate decision following p73 activation is determined by the adjustment of the balance of outcomes of p73 activation between p73-induced pro-apoptotic signaling and c-FLIP expression in p53-deficent cancer cells. Our discovery of the new function of p73 to upregulate c-FLIP provides a rationale for depleting c-FLIP to improve antitumor efficacy of p73-targeting cancer therapy.

Citation Format: Shengliang Zhang, Wafik S. El-Deiry. Therapeutic targeting of p73-activated c-FLIP switches cell fate from growth arrest and survival to apoptosis in p53-deficient 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 5854.
Abstract 5860: Five-year survival of patients with late stage prostate cancer: Comparison of the military health system with the US general population
Authors: Lin Jie , Nousome Darryl , Jiang Jiji , Chesnut Gregory , Shriver Craig , Zhu Kangmin
Published: June 2022

While the five-year survival for local and regional prostate cancer is nearly 100%, it decreases dramatically for advanced (stages III and IV) prostate cancer. Access to health care is an important factor that affects cancer prognosis. The Military Health System (MHS) provides universal health care to beneficiaries. However, it is unclear whether the universal care translates into improved survival among patients with advanced prostate cancer. We compared survival of patients with advanced prostate cancer between the MHS and the U.S. general population. The MHS patients (N= 5,379) were identified from the Department of Defense's (DoD) Automated Central Tumor Registry (ACTUR). Patients in the U.S. general population (N=21,516) were identified from the Surveillance, Epidemiology, and End Results (SEER) program. All patients were diagnosed between January 1, 1987 and December 31, 2013. The two populations were matched on age (within 5 years), race, and diagnosis year. Multivariable Cox regression hazard model was used to estimate hazard ratios (HRs) for ACTUR compared to SEER. ACTUR patients exhibited longer 5-year survival than matched SEER patients (HR=0.74, 95% CI=0.67-0.83), after adjustment for the potential confounders. In stratified analysis, the improved survival was observed for ages 50 years or older, both white and black races, all tumor stages, and grades. In stratified analysis by treatment receipt, the improved survival of ACTUR patients compared to SEER patients remained regardless of the receipt of surgery or radiation treatment. Our results suggested that MHS beneficiaries with advanced prostate cancer had longer survival than their counterparts in the U.S. general population. Universal health care in the MHS might translate into improved survival for advanced prostate cancer.

Disclaimers: The contents of this publication are the sole responsibility of the authors and do not necessarily reflect the views, opinions, or policies of the USUHS, HJF, the DoD or the Departments of the Army, Navy, or Air Force. Mention of trade names, commercial products, or organizations does not imply endorsement by the U.S. Government.

Citation Format: Jie Lin, Darryl Nousome, Jiji Jiang, Gregory Chesnut, Craig Shriver, Kangmin Zhu. Five-year survival of patients with late stage prostate cancer: Comparison of the military health system with the US general population [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 5860.
Abstract 5862: Racial disparities in pancreatic cancer: A quantitative proteo-genomic analysis
Authors: Chatterjee Digonto , Hester Jack , Srivastava Meera , Bera Alakesh
Published: June 2022

Pancreatic cancer remains a major health concern, being among the most deadly forms of cancer. It is the seventh most common cancer, yet it is the third leading cause of cancer deaths in the United States. It is estimated that in 2021, 48,220 patients will die from pancreatic cancer. Risk factors for pancreatic cancer include smoking, diabetes, obesity, chronic pancreatitis, and family history. Over 80% of the patients present with metastatic disease. Despite advances in chemotherapy, the average survival remains less than 5 years even after surgery. Genetic research on pancreatic cancer has generally only focused on familial pancreatic cancer, which is only 10% of all pancreatic cancer patients. This study focuses on finding genes that impact the survival of pancreatic cancer patients based on race, with the goal of finding genes that are race specific and can be used as biomarkers and potential targets to develop personalized treatment options. All datasets for pancreatic cancer in cBioPortal were used for this study. The data were then stratified based on race information for the patients. Three (3) racial categories, 1) White 2) African American and Black, and 3) Asian were chosen. Our analysis finds that White, African Americans and Asians have distinct copy number alterations, more specifically amplifications in specific genes, with GATA6, RECQL4, and MIB1 being only altered in White patients, PKD1L1, GARS1, and NEUROD6 only altered in Black & African American patients, and the entire 4p16.3 cytoband of genes (39 in total), only altered in Asian patients. Patients with alterations in these unique genes also had poor survival. Using the Protein Atlas, MD Anderson Cell Lines Project (MCLP) dataset and genecards.org data, we identified potential drug candidates that target the proteins encoded by these genes. Our study clearly demonstrates that race specific genetic alterations exist in pancreatic cancer and provides a foundation for the development of race specific diagnostic/prognostic biomarkers and targeted therapeutic options with better survival outcomes.

Citation Format: Digonto Chatterjee, Jack Hester, Meera Srivastava, Alakesh Bera. Racial disparities in pancreatic cancer: A quantitative proteo-genomic analysis [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 5862.