To identify potentially important genes dysregulated in pancreatic cancer, we analyzed genome-wide transcriptional analysis of pancreatic cancers and normal pancreatic duct samples and identified the transcriptional coactivator, EYA2 (Drosophila Eyes Absent Homologue-2) as silenced in the majority of pancreatic cancers. We investigated the role of epigenetic mechanisms of EYA2 gene silencing in pancreatic cancers, performed in vitro and in vivo proliferation and migration assays to assess the effect of EYA2 silencing on tumor cell growth and metastasis formation, and expression analysis to identify genes transcriptionally regulated by EYA2. We found loss of tumoral Eya2 expression in 63% of pancreatic cancers (120/189 cases). Silencing of EYA2 expression in pancreatic cancer cell lines correlated with promoter methylation and histone deacetylation and was reversible with DNA methyltransferase and HDAC inhibitors. EYA2 knockdown in pancreatic cancer cell lines increased cell proliferation. Compared to parental pancreatic cancer cells, pancreatic cancers stably-expressing EYA2 grew more slowly and had fewer metastases in orthotopic models. The transcriptional changes after stable expression of EYA2 in pancreatic cancer cells included induction of genes in the TGFbeta pathway. Epigenetic silencing of EYA2 is a common event in pancreatic cancers and stable expression EYA2 limits the growth and metastases of pancreatic adenocarcinoma.

Pancreatic ductal adenocarcinoma evolves from precursor lesions, the most common of which is pancreatic intraepithelial neoplasia (PanIN). We performed RNA-sequencing analysis of laser capture microdissected PanINs and normal pancreatic duct cells to identify differentially expressed genes between PanINs and normal pancreatic duct, and between low-grade and high-grade PanINs. One of the most highly overexpressed transcripts identified in PanIN is interleukin-2 receptor subunit gamma (IL2RG) encoding the common gamma chain, IL2Rγ. CRISPR-mediated knockout of IL2RG in orthotopically implanted pancreatic cancer cells resulted in attenuated tumor growth in mice and reduced JAK3 expression in orthotopic tumors. These results indicate that IL2Rγ/JAK3 signaling contributes to pancreatic cancer cell growth in vivo.

Ataxia telangiectasia mutated (ATM) is inactivated in a significant minority of pancreatic ductal adenocarcinomas and may be predictor of treatment response. We determined if ATM deficiency renders pancreatic cancer cells more sensitive to fractionated radiation or commonly used chemotherapeutics. ATM expression was knocked down in three pancreatic cancer cell lines using ATM-targeting shRNA. Isogenic cell lines were tested for sensitivity to several chemotherapeutic agents and radiation. DNA repair kinetics were analyzed in irradiated cells using the comet assay. We find that while rendering pancreatic cancer cells ATM-deficient did not significantly change their sensitivity to several chemotherapeutics, it did render them exquisitely sensitized to radiation. Pancreatic cancer ATM status may help predict response to radiotherapy.

The methylation status of a promoter influences gene expression and aberrant methylation during tumor development has important functional consequences for pancreatic and other cancers. Using methylated CpG island amplification and promoter microarrays, we identified ANK1 as hypomethylated in pancreatic cancers. Expression analysis determined ANK1 as commonly overexpressed in pancreatic cancers relative to normal pancreas. ANK1 was co-expressed with miR-486 in pancreatic cancer cells. Stable knockdown of ANK1 in the pancreatic cancer cell line AsPC1 led to changes in cell morphology, and decreases in colony formation. Stable knockdown of ANK1 also marked reduced the growth of tumors in athymic nude mice. Among patients undergoing pancreaticoduodenectomy, those with pancreatic cancers expressing ANK1 had a poorer prognosis than those without ANK1 expression. These findings indicate a role for ANK1 overexpression in mediating pancreatic cancer tumorigenicity.

Noonan syndrome, a distinctive syndrome characterized by dysmorphism, cardiac abnormalities and developmental delay, has been associated with a number of malignancies, however, only a few cases of primary glial or glioneuronal neoplasms have been reported. We report here the case of an 18-year-old with Noonan syndrome who developed a rosette forming glioneuronal tumor of the posterior fossa. The tumor demonstrated strong pERK immunoreactivity, suggesting MAPK/ERK pathway activation. Molecular testing did not reveal BRAF rearrangements (fusion transcripts) by PCR or a BRAF V600E mutation by sequencing. We review the literature regarding the molecular pathogenesis of Noonan syndrome and primary brain tumors, and consider the intriguing link between their common molecular pathways.

Despite some advances in our understanding of the molecular characteristics of pancreatic cancer, much more progress is needed. In a new study, RNA profiling of pancreatic cancers was used to identify gene signatures of tumour cells and stromal cells to help predict patient outcomes.

300 Background: This study evaluated rates of biomarker testing for patients with stage IV non-squamous NSCLC, which is known to have a ̃40% biomarker-positive rate (AMP, 2020), in a community-based oncology practice setting in the United States (US). Methods: A retrospective study was performed using data from a US electronic medical record database of patients aged ≥18 years with an initial diagnosis (index dx) of stage IV non-squamous NSCLC between Jan 1, 2015 and Dec 31, 2019. Unstructured data on molecular biomarker testing (single-gene and next-generation sequencing [NGS]-based) were abstracted from patient charts utilizing Natural Language Processing for EGFR mutation, ALK rearrangement, BRAF mutation, ROS1 rearrangement, MET exon14 mutation, RET fusion, NTRK fusion, and PD-L1 expression. Systemic therapy was obtained from structured data. Data were summarized using descriptive statistics. This study received a waiver of consent from Advarra IRB. Results: Of 646 patients identified in the database, 500 met all inclusion criteria and are included in this analysis. The majority (73.8%) were diagnosed in 2018 (n = 162; 32.4%) and 2019 (n = 207; 41.4%). Mean age (SD) was 70.0 (10.1) years, with 53.2% female. A total of 447 (89.4%) were tested for at least one biomarker after index diagnosis of which 81.2% (n = 406) had at least one single-gene test; 54.8% (n = 274) had an NGS test and 66.8% were tested for PD-L1. Single-gene or NGS-based testing was > 85% of patients across all index years. The use of NGS-based tests ranged from 35.0% among patients whose first diagnosis was in 2015 to 59.4% in 2019. Overall, 85.4% (n = 427) of the cohort received first-line treatment with chemotherapy (53.6%), immunotherapy (48.2%), or targeted therapy (14.2%). Among patients who received biomarker tests, 15.4% received targeted treatment and 49.7% received immunotherapy treatment, including checkpoint inhibitors, during first-line treatment. Conclusions: NGS testing utilization increased during the study period and by 2019, 59% of patients received NGS-based testing. Opportunities persist for practices to improve testing and achieve guideline recommendations. PD-L1 biomarker testing was performed amongst the highest proportion of patients in this study and nearly 50% of all patients received immunotherapy, including checkpoint inhibitors. Targeted therapy was used in 14.2% of this population, suggesting that patients with actionable biomarkers may not be receiving targeted treatment for their disease, potentially due to gaps in testing among patients in this dataset.

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