Abstract:

Objective To explore the effect of circular RNA （circRNA）-15430 on the proliferation and invasion of gastric cancer cells by regulating mircoRNA-10 （miR-10）. Methods The relative expression levels of circRNA-15430 and miR-10 in gastric epithelial cell line GES-1 and four gastric cancer cell lines （GTL16， NUGC-3， MGC803， Snu-1） were detected by real-time fluorescence quantitative PCR. The gastric cancer cell line GTL16 were taken， and the cells were divided into the gastric cancer cell （GC） group， the gastric cancer cell+circRNA-15430-NC （CN） group， the gastric cancer cell+circRNA-15430 inhibitor （CI） group， the gastric cancer cell +circRNA-15430 agonist （CM） group， the gastric cancer cell+miR-10-NC （MN） group， the gastric cancer cell+miR-10 agonist （MM） group， the gastric cancer cell+miR-10 inhibitor （MI） group， and the gastric cancer cell+circRNA-15430 agonist+miR-10 inhibitor （UI） group. Cell proliferation was detected by the CCK-8 method， and cell invasion was detected by the Transwell chamber method. The dual-luciferase reporter gene assay was used to confirm the interaction between circRNA-15430 and miR-10. Results Real-time fluorescence quantitative PCR showed that the relative expression levels of circRNA-15430 in GES-1 and four types of gastric cancer cells were 1.00±0.00， 0.31±0.02， 0.62±0.04， 0.59±0.03 and 0.63±0.05， respectively， with a statistically significant difference （F=334.70， P<0.001）； The relative expression levels of miR-10 in GES-1 and four types of gastric cancer cells were 1.00±0.00， 1.80±0.18， 1.53±0.14， 1.49±0.13 and 1.51±0.15， respectively， with a statistically significant difference （F=27.52， P<0.001）. The relative expression levels of circRNA-15430 in the four types of gastric cancer cells were all lower than those in GES-1 cells， and the relative expression levels in NUGC-3， MGC803， and Snu-1 cells were all higher than those in GTL16 cells （all P<0.05）. The relative expression levels of miR-10 in the four types of gastric cancer cells were all higher than those in GES-1 cells （all P<0.05）， and the relative expression levels in NUGC-3， MGC803， and Snu-1 cells were all lower than those in GTL16 cells （all P<0.05）. Therefore， GTL16 cells were selected as the experimental cells for this experiment. The results of the cell proliferation and invasion assay showed that the cell proliferation rates of the GC group， CN group， CI group and CM group were （47.06±4.61） %， （47.04±4.63） %， （68.61±6.59） % and （28.52±2.16） %， respectively， with a statistically significant difference （F=71.02， P<0.001）. The invasion numbers were 195.57±20.04， 195.35±20.08， 316.86±32.20 and 169.04±16.11， respectively， with a statistically significant difference （F=50.18， P<0.001）. The cell proliferation rate and invasion number in the CI group were both higher than those in the GC group and CN group， while the cell proliferation rate and invasion number in the CM group were both lower than those in the GC group， CN group and the CI group （all P<0.05）. The cell proliferation rates of the MN group， MM group， and MI group were （47.18±4.62） %， （68.68±6.36） % and （28.55±2.12） %， respectively. The invasion numbers were 195.78±20.07， 316.90±32.21 and 169.10±16.15， respectively. There were statistically significant differences in cell proliferation rates and the invasion numbers among the GC group， MN group， MM group and MI group （F=73.79， P<0.001； F=50.08， P<0.001）. The cell proliferation rate and invasion number in the MM group were both higher than those in the GC group and MN group， while the cell proliferation rate and invasion number in the MI group were both lower than those in the GC group， MN group and the MM group （all P<0.05）. The cell proliferation rate in the UI group was （20.31±1.11） %， and the invasion number was 107.51±10.02. There were statistically significant differences in cell proliferation rates and invasion numbers among the CM group， MI group and UI group （F=39.06， P<0.001； F=36.63， P<0.001）. The cell proliferation rate and invasion number in the UI group were both lower than those in the CM group and MI group （all P<0.05）. The results of the dual-luciferase reporter gene assay showed that transfection with circRNA-15430 could significantly reduce the luciferase activity of miR-10-3'-UTR-WT （t=21.22， P<0.001）， but had no significant effect on the mutant gene （t=0.85， P=0.413）. Conclusions circRNA-15430 can effectively inhibit the proliferation and invasion of gastric cancer cells， and its mechanism may be related to the targeted inhibition of miR-10.

Key words: Stomach neoplasms, Cell proliferation, Neoplasm invasiveness, circRNA-15430, miR-10