Chanjiao Yao

LncRNA FAM225B Regulates PDIA4-Mediated Ovarian Cancer Cell Invasion and Migration via Modulating Transcription Factor DDX17

Objective. This study aimed to explore the roles and mechanisms of lncRNA FAM225B and PDIA4 in ovarian cancer. Methods. RT-qPCR and Western blot assays were performed to detect the expression levels of the lncRNAs FAM225B, DDX17, and PDIA4 in the serum of patients with ovarian cancer and cell lines. Cells were transfected with lncRNA FAM225B- and PDIA4-related vectors to determine the malignant phenotypes using functional experiments. The mutual binding of lncRNA FAM225B and DDX17 was verified using RNA pull-down and RIP assays. Results. The expression of lncRNAs FAM225B and PDIA4 was decreased in the serum of patients with ovarian cancer and cell lines. Restoration of lncRNA FAM225B or PDIA4 reduced cell proliferation, migration, and invasion abilities and elevated the apoptosis rate, whereas suppression of lncRNA FAM225B or PDIA4 exhibited an inverse trend. RNA pull-down and RIP assays revealed a direct interaction between lncRNA FAM225B and DDX17. ChIP assay revealed a relationship between DDX17 and the PDIA4 promoter. LncRNA FAM225B and DDX17 positively regulate PDIA4 expression. Downregulation of PDIA4 expression counteracts the suppressive effect of lncRNA FAM225B overexpression in ovarian cancer cells. Conclusion. This research study supports the fact that lncRNA FAM225B in ovarian cancer can upregulate PDIA4 by directly binding to DDX17, inhibiting the activities of ovarian cancer cells.

MicroRNA‐378a‐3p contributes to ovarian cancer progression through downregulating PDIA4

AbstractObjectiveMicroRNAs, as essential players in tumorigenesis, have been demonstrated to have a revolutionary effect on human cancer research. Ovarian cancer is the primary reason of death among gynecologic malignancies. In view of this, it is significant to identify prognostic and predictive markers for treatment of ovarian cancer. The aim of this study was to probe into the effects of miR‐378a‐3p and protein disulfide‐isomerase A4 (PDIA4) on the biological functions of ovarian cancer cells.MethodsmiR‐378a‐3p expression and PDIA4 messenger RNA expression in human ovarian cancer cells, normal human ovarian epithelial cells, and serum of both ovarian cancer patients and healthy people were detected by reverse transcription‐quantitative polymerase chain reaction, and the PDIA4 protein expression was tested by Western blot analysis. Ovarian cancer OVCAR3 and SKOV3 cells were transfected or cotransfected with miR‐378a‐3p mimic or pcDNA3.1‐PDIA4 or their negative control plasmids to explore their roles in biological functions in ovarian cancer cells. Luciferase activity and RIPA assays were implemented to validate the interaction between miR‐378a‐3p and PDIA4. Western blot analysis was utilized to detect phosphatidylinositol‐3 kinase/serine/threonine kinase (PI3K/AKT) signaling pathway‐related protein expression and their phosphate expression levels.ResultsmiR‐378a‐3p was elevated and PDIA4 was decreased in ovarian cancer cells and serum. In addition, miR‐378a‐3p mimic induced ovarian cancer cell growth, while miR‐378a‐3p inhibitor and pcDNA3.1‐PDIA4 presented an inverse trend. pcDNA3.1‐PDIA4 partially eliminated the capabilities of miR‐378a‐3p mimic on ovarian cancer progression. Meanwhile, miR‐378a‐3p was found to negatively regulate PDIA4, and miR‐378a‐3p mimic increased the phosphorylation levels of AKT and PI3K, while pcDNA3.1‐PDIA4 exhibited an opposite tendency. Furthermore, pcDNA3.1‐PDIA4 largely eliminated the functions of miR‐378a‐3p mimic on phosphorylation levels of AKT and PI3K.ConclusionThis study provides evidences that miR‐378a‐3p activates PI3K/AKT signaling pathway by modulating PDIA4 expression, thereby playing a role in promoting the growth of ovarian cancer cells. This study provides novel directions for targeted therapy of ovarian cancer.

Histone Deacetylation Regulated by KDM1A to Suppress DACT1 in Proliferation and Migration of Cervical Cancer

Objective. Increased expression of KDM1A and decreased expression of DACT1 in cervical cancer cells were noticed in a previous study. This study is aimed at exploring the mechanism behind the KDM1A regulation on DACT1 in cervical cancer cells. Methods. The expression profile of KDM1A and DACT1 in cervical cancer tissues was searched in TCGA database. In vitro experiments verified the effect of KDM1A and DACT1 on proliferation and migration ability of cervical cancer cell lines after cell transfection. The interaction of KDM1A with HDAC1 was identified by coimmunoprecipitation (Co-IP). The expression levels of KDM1A and DACT1 in cervical cancer cell lines were determined by qRT-PCR and western blot. Results. TCGA database showed that cervical cancer tissues had elevated expression of KDM1A and decreased expression of DACT1, which was consistent with the observation in cervical cancer cell lines. KDM1A was found to negatively regulate DACT1 through histone deacetylation. Meanwhile, the downregulation of KDM1A or overexpression of DACT1 could suppress the cell proliferation and migration ability in HeLa and SiHa cells. Cotransfection of KDM1A and DACT1 overexpression could reverse the increased cell proliferation and migration ability induced by KDM1A overexpression. Conclusion. KDM1A can downregulate DACT1 expression through histone deacetylation and therefore suppress the proliferation and migration of cervical cancer cells.