Effects of long noncoding RNA small ubiquitin-like modifier 1 pseudogene 3 on proliferation and apoptosis of gastric cancer cells

Abstract

Objective To investigate the expression level of long noncoding RNA (lncRNA) small ubiquitin-like modifier 1 pseudogene 3(SUMO1P3) in gastric cancer tissues and the its effects on proliferation and apoptosis of gastric cancer cells. Methods The expression level of SUMO1P3 in 63 clinical samples of gastric cancer tissues and adjacent normal tissues, and gastric cancer cell lines (MGC803, AGS, BSG823, SGC7901) and normal gastric cell line (GES-1) were measured by real-time quantitative reverse-transcriptase polymerase chain reaction (RT-qPCR). The MGC803 cells were divided into two groups: the small interfering RNA group (si-SUMO1P3) and the negative control group (si-Ctrl). The influence of SUMO1P3 interference on the capacities of cell proliferation, colony formation, cell migration and cell apoptosis were evaluated with cell counting kit-8 (CCK-8), colony formation assay, scratch healing experiment and flow cytometry, respectively. Results The relative expression level of SUMO1P3 was significantly higher in gastric cancer tissues (2.37±0.59) than that in adjacent normal tissues (0.91±0.28) (t=17.740, P<0.01), and SUMO1P3 was overexpressed in gastric cancer cell lines MGC803, AGS, BSG823, SGC7901 compared with GSE-1 (P<0.05). The expression of lncRNA SUMO1P3 in MGC803 cells was significantly repressed by small interfering RNA (siRNA). The results of CCK-8 assay showed that the absorbance value of si-SUMO1P3 group (2.22±0.14) was significantly lower than that of si-Ctrl group (3.12±0.13, t=4.730, P<0.01) after culturing 72 h. The colony formation results revealed that the colony forming ability of si-SUMO1P3 group (26.2±5.5)% was significantly impaired compared with si-Ctrl group (47.3±6.9)% (t=4.140, P<0.05). The scratch healing experiment indicated that the cell migration rate of si-SUMO1P3 group (21.7±4.1)% was significantly lower than that of si-Ctrl group (35.3±5.8)% (t=3.320, P<0.05) after incubating 24 h. Flow cytometry results suggested that cell apoptosis of si-SUMO1P3 group (16.4±2.3)% was significantly increased compared with si-Ctrl group (7.3±1.6)% (t=5.630, P<0.01). Conclusion LncRNA SUMO1P3 was highly expressed in gastric cancer tissues. Interfering the expression of SUMO1P3 could inhibit the proliferation and induce cell apoptosis of gastric cancer cells. Key words: Gastric cancer; Long noncoding RNA; Small ubiquitin-like modifier 1 pseudogene 3; Proliferation; Apoptosis