Varying miR-193b-3p Expression Patterns in Breast Cancer Cell Lines Indicates Its Potential for Cancer Management Strategies

Abstract

Background: Metastasis-associated miRNA (metastamiR) harbors a great potential to confine metastasis as the most lethal aspect of cancer. miR-193b-3p is an anti-metastatic miRNA, whose expression significantly decreases in metastatic breast cancer cells. Objectives: In the present study, the expression patterns of different cell-lines were investigated, following an effective miR transfection strategy. Methods: Double-stranded oligo of mature miR-193b-3p, miR-negative, and miR-LacZ were designed and cloned into pcDNA6.2gw/EmGFP plasmid. Calculating the population doubling time (PDT), non-tumorigenic MCF-10A, tumorigenic but non-metastatic MCF-7, and metastatic MDA-MB231 were transfected by Lipofectamin2000 and Express-In. The expressions of miR-193b-3p and miR-191 have been quantified by Real-time PCR 48 hours after transfection. Scratch, Transwell migration, and Matrigel invasion assays have been carried out to assess the migration and invasion levels of the cell-lines. Results: The PDT (21.27 ± 0.43, 28.18 ± 0.34, and 35.83 ± 0.44 hours) and miR-193b-3p relative expression before transfection (100, 42 and 8) were measured for MCF-10A, MCF-7, and MDA-MB231 cell-lines, respectively. Better transfection results were obtained based on nano-liposome method. The expression of the miR-193b-3p was increased 32, 19 and, 65 fold-change. The rate of invasion in metastatic cells was 6.6 fold-higher in comparison to MCF-7 cells. Conclusions: Higher expression rate of the miRNA is anticipated to occur, following miR-mimic transfection. However, the observed differential patterns of miRNA increase in the context of different cell-lines, indicating the involvement of more complicated cellular pathways. Scrutinizing these cellular mechanisms could open new horizons in cancer therapy and management strategies.