Effects of small interfering RNA specific to stably transfected HMGA1 gene on biological characters of ovarian carcinoma cells

Abstract

To investigate the effects of biological characters of the human ovarian cell line (OVCAR) by stable transfection short hairpin RNA into the target HMGA1 gene. Experiments were divided into two groups: transfected the OVCAR cells with pSilence4.1-CMV-Hs plasmid as group A, while transfected OVCAR cells with pSilence4.1-CMV-Hn plasmid as group B, in which stably transfected cells were gained by antibiotic screening. The comparative expressions of HMGA1 were detected by RT-PCR and western blot. Methyl thiazolyl tetrazolium (MTT) method was applied to measure cell proliferation and at the same time, the cell growth curve was also be mapped. Vitro invasion assay was used to observe the invasion ability of the cancer cells, and the tumor growth of the nude mice inoculated of tumor cells were compared with before and after transfection. In group A, the expression level of mRNA and protein HMGA1 gene in OVCAR cells were remarkably reduced before and after the stable transfected with HMGA1 siRNA, in which the percents of mRNA expression were [(86.3 ± 2.7)% vs. (35.8 ± 3.1)%, P < 0.05], the expression of protein were [(68.6 ± 2.8)% vs. (22.3 ± 4.2)%, P < 0.05)]. The OVCAR cell growth in stable transfection status was more significantly decreased than that in non-transfection status (P < 0.05). In group B, there were no statistical difference in the expression of HMGA1 siRNA, protein and the cell growth between before and after transfection states (P > 0.05). The invasion cell numbers were reduced from before to after transfection state in group A [(53 ± 6) vs. (21 ± 6), P < 0.05], while there was no significant difference in group B [(51 ± 6) vs. (47 ± 8), P > 0.05]. After inoculated transfected cells into nude mice, it took (6.0 ± 0.9) days to grow the planed tumors in group A, which was much shorter than that (12.3 ± 3.9) days in group B (P < 0.05). After 5 weeks, the tumor weight and volume in group A was were significantly lower than those in group B [(0.8 ± 0.3) g vs. (2.1 ± 0.4) g, (205 ± 34) mm(3) vs. (987 ± 82) mm(3), all P < 0.05]. HMGA1 siRNA could remarkably reduce the expression of HMGA1 gene in ovarian cell and also inhabit the ovarian cell growth.