The Effect of hsa-miR-451b Knockdown on Biological Functions of Gastric Cancer Stem-Like Cells.

Numerous researches have extensively studied factors such as microRNAs that lead to cancer. Thus, the current study's purpose is to investigate the biological consequences of hsa-miR-451b inhibition on the properties and functions of gastric cancer stem-like cells. First, gastric cancer stem-like cells were transfected by hsa-miR-451b inhibitor then we used real-time RT-PCR to evaluate its effect on the expression of hsa-miR-451b and two of its direct target genes, Stemness markers such as KLF4, SOX2, CD44, OCT3/4 and NANOG genes and finally Akt, PI3K, Bcl-2, Bax, CASP3 and PCNA genes involved in apoptosis. Here, we conducted a DNA Laddering assay to investigate apoptosis. The level of the MMP-2 and -9 Activities and Migration were examined by Zymography and Transwell invasion assay. HUVEC cells were used to investigate angiogenesis. The outcomes revealed that the level of the MMP-2 and -9 Activities, migration and angiogenesis decreased, but apoptosis was induced by inhibiting hsa-miR-451b. Evaluating KREMEN1 and CASK expression showed that the former increased, and the latter dropped under hsa-miR-451b inhibition. Also, upregulation of the KLF4 and SOX2 and downregulation of the CD44, OCT3/4, and NANOG decreased Self-renewal ability of gastric cancer stem cells under hsa-miR-451b inhibition. Even, under hsa-miR-451b inhibition, downregulation of Akt, PI3K, Bcl-2 and PCNA as well as upregulation of Bax and CASP3 revealed a movement towards apoptosis in MKN-45 stem-like cells. In summary, hsa-miR-451b is an oncomir in the carcinogenesis of gastric cancer stem-like cells and may be suggested as an appropriate therapeutic target for future gastric cancer treatment.