ABSTRACT
ABSTRACT Background: Cervical cancer (CC), as a serious menace to the health of women, has long been one of the most lethal gynecologic neoplasms throughout the world. Long non-coding RNA (LncRNA) NR2F1-AS1 has been documented to exert crucial functions in many malignant tumors. Nonetheless, the function and molecular mechanism of NR2F1-AS1 in CC remain completely unknown. Objective: This study aimed to explore the function and molecular mechanism of NR2F1-AS1 in CC. Methods: The expression levels of NR2F1-AS1, miR-642a-3p, NR2F1 in CC tissues, and cell lines were examined by reverse transcription real-time quantitative polymerase chain reaction. Cell viability, proliferation, migration, and invasion were detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, colony formation and Transwell assays. The protein levels of epithelial-mesenchymal transition markers and NR2F1 in CC cells were assessed by Western blot analysis. The correlations among NR2F1-AS1, miR-642a-3p, and NR2F1 were estimated through luciferase reporter and RNA immunoprecipitation assays. Results: NR2F1-AS1 expression was clearly downregulated in CC tissues and cell lines. Molecular mechanistic experiments showed that NR2F1-AS1 overexpression upregulated NR2F1 expression in CC cells by directly binding to miR-642a-3p, and inhibiting by this way cell viability, proliferation, migration, and invasion in CC. Rescue assays showed that NR2F1 knockdown or miR-642a-3p overexpression offset NR2F1-AS1 upregulation-induced inhibition on CC cell malignant phenotypes. Conclusion: These findings revealed that NR2F1-AS1 played a tumor suppressor role in CC by mediating the miR-642a-3p/NR2F1 axis.
ABSTRACT
The biological functions of the BC047440 gene highly expressed by hepatocellular carcinoma (HCC) are unknown. The objective of this study was to reconstruct antisense eukaryotic expression vectors of the gene for inhibiting HepG2 cell proliferation and suppressing their xenograft tumorigenicity. The full-length BC047440 cDNA was cloned from human primary HCC by RT-PCR. BC047440 gene fragments were ligated with pMD18-T simple vectors and subsequent pcDNA3.1(+) plasmids to construct the recombinant antisense eukaryotic vector pcDNA3.1(+)BC047440AS. The endogenous BC047440 mRNA abundance in target gene-transfected, vector-transfected and naive HepG2 cells was semiquantitatively analyzed by RT-PCR and cell proliferation was measured by the MTT assay. Cell cycle distribution and apoptosis were profiled by flow cytometry. The in vivo xenograft experiment was performed on nude mice to examine the effects of antisense vector on tumorigenicity. BC047440 cDNA fragments were reversely inserted into pcDNA3.1(+) plasmids. The antisense vector significantly reduced the endogenous BC047440 mRNA abundance by 41 percent in HepG2 cells and inhibited their proliferation in vitro (P < 0.01). More cells were arrested by the antisense vector at the G1 phase in an apoptosis-independent manner (P = 0.014). Additionally, transfection with pcDNA3.1(+)BC047440AS significantly reduced the xenograft tumorigenicity in nude mice. As a novel cell cycle regulator associated with HCC, the BC047440 gene was involved in cell proliferation in vitro and xenograft tumorigenicity in vivo through apoptosis-independent mechanisms.