ABSTRACT
@# Objective: To investigate the expression of ECT2 (epithelial Transforming sequence 2) gene in human pancreatic ductal adenocarcinoma (PDAC) and its effect on the proliferation and apoptosis of pancreatic cancer cells. Methods: Carcinoma tissues and corresponding para-carcinoma tissues from 35 PDAC patients at Changhai Hospital Affiliated to Naval Medical University from July 2018 to March 2019 were collected for this study. The differentially expressed genes in pancreatic cancer were screened out by using Gene Expression Omnibus (GEO) Database. Then, the related gene expression in PDAC and its relation with patients’survival were analyzed by The Cancer Genome Atlas (TCGA) database. QPCR and immunohistochemistry were used to verify the mRNAand protein expressions of ECT2 in human PDAC samples. To explore the effect of ECT2 on the biological behaviors of pancreatic cancer cells, si-RNA was used to silence the ECT2 gene in pancreatic cancer PANC-1 cells, and CCK-8 proliferation assay and Flow cytometry were used to detect the proliferation and apoptosis rate of PANC-1 cells after ECT2 silence. Finally, the expressions of apoptosis-related proteins were detected by WB. Results: The differentially expressed gene-ECT2, was screened out by analyzing the gene expression profiles of human pancreatic cancer in GEO database. TCGA database analysis showed that ECT2 was highly expressed in pancreatic cancer tissues (t=4.005, P<0.05) and significantly correlated with patients’survival (P< 0.01). Moreover, it is also verified that ECT2 was highly expressed in PDAC tissues at mRNA (1.01±0.06 vs 4.25±0.12; t=24.09， P<0.01) and protein level. After ECT2 silence in PANC-1 cells, the proliferation rate was decreased (P<0.01), while the Tamoxifeninduced apoptosis rate was increased (P<0.01), and the expressions of apoptosis-related proteins (BAX and Bcl-2) were also affected. Conclusion: ECT2 is highly expressed in human pancreatic ductal adenocarcinoma and is related with patients’survival. ECT2 promotes the proliferation and apoptosis resistance of pancreatic cancer cells, providing the basis for exploring ECT2 as a new target for the prognostic judgment and treatment of pancreatic cancer.
ABSTRACT
Resumen El cáncer de páncreas es una enfermedad mortal, principalmente porque se descubre muy tarde y es muy resistente a la quimioterapia y radioterapia. El tipo más común de cáncer de páncreas (más del 90%) se desarrolla a partir de las células exocrinas del páncreas y se denomina adenocarcinoma ductal pancreático (ACDP). Se han reconocido tres lesiones precursoras de cáncer de páncreas ductal: neoplasia intraepitelial pancreática (PanIN), neoplasia papilar-mucinosa intraductal (NPMI) y neoplasia quística mucinosa (NCM). Uno de los primeros eventos genéticos implicados en la patogénesis de ACDP es una mutación en el punto de activación en el oncogén KRAS, una mutación conductora oncogénica que se encuentra en más del 90% de todos los cánceres de páncreas. Además, se ha informado que hasta un 10% de los cánceres de páncreas están asociados con el historial familiar. Aunque la causa es multifactorial, el tabaquismo y la historia familiar son dominantes. Existe heterogeneidad morfológica en muchos cánceres humanos, pero parece ser un hallazgo particularmente común en ACDP. La cirugía solo es posible en 15-20% de los casos: tumores confinados al páncreas con posible afectación ganglionar local no muy extensa y que no produce afectación vascular o está limitada.
Abstract Pancreatic cancer is a deadly disease, mainly because it is generally discovered very late and it is very resistant to chemotherapy and radiation therapy. The most common type of pancreatic cancer (over 90%) develops from the exocrine cells of the pancreas and is named pancreatic ductal adenocarcinoma (PDAC). Three precursor lesions of ductal pancreatic cancer have been recognized: pancreatic intraepithelial neoplasia (PanIN), intraductal papillary-mucinous neoplasm (IPMN) and mucinous cystic neoplasm (MCN). One of the earliest genetic events involved in PDAC pathogenesis is an activating point mutation in the KRAS oncogene, an oncogenic driver mutation found in more than 90% of all pancreatic cancer. In addition, it has been reported that up to 10% of pancreatic cancer is associated with family history. Although the cause is multifactorial, cigarette smoking and family history are dominant. Morphological heterogeneity exists in many human cancers, but seems to be a particularly common finding in PDAC. Surgery is only possible in 15-20% of cases: tumors confined to the pancreas with possible local nodal involvement not very extensive and that do not produce vascular involvement or is limited.