Long noncoding RNA LEF1-AS1 silencing suppresses the initiation and development of prostate cancer by acting as a molecular sponge of miR-330-5p via LEF1 repression.

Prostate cancer (PCa) is one of the major cancers affecting males with high mortality around the world. Recent studies have found that some long noncoding RNAs play a critical part in the cellular processes of PCa. In our study, aberrant expressed lymphoid enhancer-binding factor-1 antisense RNA 1 (LEF1-AS1), microRNA-330-5p (miR-330-5p), and lymphoid enhancer-binding factor-1 (LEF1) were screened out from a microarray database, the role of the novel noncoding RNA regulatory circuitry in the initiation and development of PCa was investigated. LEF1-AS1 and LEF1 were highly expressed while miR-330-5p was poorly expressed in PCa. Following that, the PCa PC-3 cell line was adopted for subsequently experiments, in which the expression of LEF1-AS1 and miR-330-5p was subsequently altered by means of exogenous transfection. After that, the effects of up- or downregulation of LEF1-AS1 and miR-330-5p on epithelial-mesenchymal transition (EMT) and the cell ability for proliferation, invasion, migration in vitro, and tumorigenesis and lymph node metastasis (LNM) in vivo were evaluated. RNA crosstalk revealed that LEF1-AS1 bound to miR-330-5p and LEF1 was the target gene of miR-330-5p. Silenced LEF1-AS1 or elevated miR-330-5p exhibited inhibited EMT processes, reduced ability of proliferation, invasion and migration, coupling with decreased tumorigenesis and LNM in nude mice. The key findings of this study collectively propose downregulation of LEF1-AS1 competing with miR-330-5p to inhibit EMT, invasion and migration of PCa by LEF1 repression.

The antitumor effect of the novel cancer-specific adenovirus Ad-VEGFR on bladder cancer in vitro and in vivo.

Bladder cancer is one of the most common cancers. Approaches that block tumor angiogenesis are a new therapeutic strategy for locally advanced or metastatic BC. VEGF/VEGFR signaling has been obviously and negatively correlated with the progression and invasion of cancer. In this study, we constructed the recombinant adenovirus vAd-VEGFR-3 to investigate its antitumor effector in vitro/vivo. First, we used the recombinant adenovirus vAd-VEGFR-3 to infect bladder cancer cells and then collected the cell culture supernatant to treat human umbilical vein endothelial cells (HUVECs). The proliferation, migration and apoptosis of HUVECs were respectively detected by MTT, transwell and Annexin V-FITC/PI double staining. In addition, mouse bladder mucosa was injured by trypsin, and the orthotopic transplantation model of human bladder cancer was successfully constructed to clarify the anti-tumor effect of Ad-VEGFR in vivo. The results showed that Ad-VEGFR could inhibit the cancer's proliferation and migration, while promoting the apoptosis of HUVECs in vitro. Moreover, Ad-VEGFR could significantly promote the apoptosis of bladder cancer cells and then prevent tumor growth in vivo. In addition, it also down-regulated the expression levels of CD31, an endothelial cell marker which is closely related to the angiogenesis. Taken together, it suggests that the infection of adenovirus-carrying VEGFR in bladder cancer cells may inhibit blood vessel formation and prevent tumor progression.