miR-502 inhibits cell proliferation and tumor growth in hepatocellular carcinoma through suppressing phosphoinositide 3-kinase catalytic subunit gamma.

MicroRNAs (miRNAs) play a key role in carcinogenesis and tumor progression in hepatocellular carcinoma (HCC). In the present study, we demonstrated that miR-502 significantly inhibits HCC cell proliferation in vitro and tumor growth in vivo. G1/S cell cycle arrest and apoptosis of HCC cells were induced by miR-502. Phosphoinositide 3-kinase catalytic subunit gamma (PIK3CG) was identified as a direct downstream target of miR-502 in HCC cells. Notably, overexpression of PIK3CG reversed the inhibitory effects of miR-502 in HCC cells. Our findings suggest that miR-502 functions as a tumor suppressor in HCC via inhibition of PI3KCG, supporting its utility as a promising therapeutic gene target for this tumor type.

Isolation and partial characterization of an antifungal protein produced by Bacillus licheniformis BS-3.

An antifungal protein produced by Bacillus licheniformis strain BS-3 was purified to homogeneity by ammonium sulfate precipitation, DEAE-52 column chromatography and Sephadex G-75 column chromatography. The purified protein was designated as F2 protein, inhibited the growth of Aspergillus niger, Magnaporthe oryzae and Rhizoctonia solani. F2 protein was a monomer with approximately molecular weight of 31 kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gave a single peak on High Performance Liquid Chromatography (HPLC). Using Rhizoctonia solani as the indicator strain, the EC50 of F2 protein was 35.82 µg/mL, displaying a higher antifungal activity in a range of pH 6.0 to pH 10.0, and at a temperature below 70 °C for 30 min. F2 protein was moderately resistant to hydrolysis by trypsin, proteinase K, after which its relative activities were 41.7% and 59.5%, respectively. F2 protein was assayed using various substrates to determine the enzymatic activities, the results showed the hydrolyzing activity on casein, however, no enzymatic activities on colloidal chitin, CM-cellulose, xylan, M. lysodeikticus, and p-nitrophenyl-N-acetylglucosaminide.