Shengxun Mao1, Nan He2, Lin Xin2, Fei Zeng2, Jiaqing Cao2. 1. Department of Gastrointestinal Surgery, the Second Affiliated Hospital of Nanchang University, Nanchang 330006, China. Email: maoshengxun@126.com. 2. Department of Gastrointestinal Surgery, the Second Affiliated Hospital of Nanchang University, Nanchang 330006, China.
Abstract
OBJECTIVE: To observe the effects of miR-224 antisense oligonucleotide (ASO) on the proliferation and apoptosis of gastric cancer cells in vitro and vivo. METHODS: The expression of miR-224 in the cancer tissues and their adjacent tissues in 120 gastric cancer patients were detected by real-time quantitative PCR. The biological effects of miR-224 ASO on human gastric cancer SGC7901 cells was assessed by MTT assay, clone formation assay, flow cytometry and in vivo experiment in nude mice. RESULTS: Compared with the control group (0.50 ± 0.07), miR-224 ASO significantly reduced the miR-224 mRNA expression in the cancer patients (0.09 ± 0.01, P < 0.05). MTT assay results showed that the survival rate of gastric cells at 24 h, 48 h and 72 h was 53.6%, 59.1% and 70.1% in the miR-224 ASO group, and 12.3%, 17.4% and 24.7%, respectively, in the control group (P < 0.05 for all). Clone formation assay revealed that clone formation rate in the miR-224 ASO group was (5.33 ± 0.74)%, significantly lower than the (33.33 ± 8.38)% in the control group (P < 0.05). Flow cytometry indicated that the apoptotic index was (15.68 ± 1.46)% in the miR-224 ASO group and (3.36 ± 0.88)% in the control group (P < 0.01). In addition, the expressions of Bcl2 mRNA and protein were 1.05 ± 0.04 and 0.21 ± 0.03 in the miR-224 ASO group, significantly lower than that in the control group (4.87 ± 0.96 and 0.88 ± 0.09, P < 0.01). The in vivo study further showed that the tumor volume in the experimental group is significantly smaller than that in the control group (P = 0.01). CONCLUSIONS: MiR-224 is overexpressed in human gastric cancer. Reducing the expression of miR-224 can effectively inhibit the growth and promote apoptosis of gastric cancer cells. miR-224 may become a new target for the regulation of gene expression in gastric cancer.
OBJECTIVE: To observe the effects of miR-224 antisense oligonucleotide (ASO) on the proliferation and apoptosis of gastric cancer cells in vitro and vivo. METHODS: The expression of miR-224 in the cancer tissues and their adjacent tissues in 120 gastric cancerpatients were detected by real-time quantitative PCR. The biological effects of miR-224ASO on humangastric cancer SGC7901 cells was assessed by MTT assay, clone formation assay, flow cytometry and in vivo experiment in nude mice. RESULTS: Compared with the control group (0.50 ± 0.07), miR-224ASO significantly reduced the miR-224 mRNA expression in the cancerpatients (0.09 ± 0.01, P < 0.05). MTT assay results showed that the survival rate of gastric cells at 24 h, 48 h and 72 h was 53.6%, 59.1% and 70.1% in the miR-224ASO group, and 12.3%, 17.4% and 24.7%, respectively, in the control group (P < 0.05 for all). Clone formation assay revealed that clone formation rate in the miR-224ASO group was (5.33 ± 0.74)%, significantly lower than the (33.33 ± 8.38)% in the control group (P < 0.05). Flow cytometry indicated that the apoptotic index was (15.68 ± 1.46)% in the miR-224ASO group and (3.36 ± 0.88)% in the control group (P < 0.01). In addition, the expressions of Bcl2 mRNA and protein were 1.05 ± 0.04 and 0.21 ± 0.03 in the miR-224ASO group, significantly lower than that in the control group (4.87 ± 0.96 and 0.88 ± 0.09, P < 0.01). The in vivo study further showed that the tumor volume in the experimental group is significantly smaller than that in the control group (P = 0.01). CONCLUSIONS:MiR-224 is overexpressed in humangastric cancer. Reducing the expression of miR-224 can effectively inhibit the growth and promote apoptosis of gastric cancer cells. miR-224 may become a new target for the regulation of gene expression in gastric cancer.