姜黄素调控PTEN/miR⁃182⁃5p轴抑制乳腺癌发生发展的机制研究

Mechanism of curcumin regulating PTEN/miR⁃182⁃5p axis to inhibit the occurrence and development of breast cancer

目的探究姜黄素调控人第10号染色体缺失的磷酸酶及张力蛋白同源基因(PTEN)PTEN/miR⁃182⁃5p轴抑制乳腺癌发生发展的机制。方法取人乳腺癌细胞株MCF⁃7进行体外培养并获得对数生长期细胞,加入不同浓度姜黄素,比较不同浓度姜黄素对乳腺癌细胞的抑制效率;按照实验需求,将体外培养的MCF⁃7细胞分为正常对照组、A组(姜黄素处理)、B组(姜黄素+转染miR⁃182⁃5p模拟物)、C组(姜黄素+转染PTEN抑制剂BpV+miR⁃182⁃5p抑制物),通过RT⁃PCR检测各组细胞PTEN、miR⁃182⁃5p表达水平;Western blot检测与细胞增殖、凋亡、转移侵袭相关的KI67、半胱氨酸蛋白酶3(Caspase 3)、基质金属蛋白酶⁃2(MMP⁃2)以及MMP⁃9蛋白表达水平。结果姜黄素处理24 h、48 h均对乳腺癌细胞MCF⁃7的增殖具有抑制作用,且随姜黄素浓度升高抑制率呈上升趋势:80μmol/L抑制率>60μmol/L抑制率>40μmol/L抑制率>20μmol/L抑制率(F=276.512、255.478,P<0.05)。与正常对照组比较,A、B、C三组PTEN表达水平均升高(F=11.536,P<0.05),miR⁃182⁃5p表达水平均降低(F=10.896,P<0.05);与正常对照组比较,A、B、C组KI67、MMP⁃2、MMP⁃9蛋白表达均下降(F=10.569、10.412、8.210,P<0.05),Caspase 3表达上升(F=11.911,P<0.05)。结论姜黄素可通过调控PTEN/miR⁃182⁃5p轴,促进凋亡因子Caspase 3表达,抑制细胞增殖、转移及侵袭相关蛋白表达,发挥对乳腺癌发生发展过程的抑制。

Objective To explore the mechanism by which curcumin regulates the phosphatase and tensin homologous gene(PTEN)of human chromosome 10 deletion(PTEN)PTEN/miR⁃182⁃5p axis to inhibit the occurrence and development of breast cancer.Methods The human breast cancer cell line MCF⁃7 was cultured in vitro,and logarithmic growth cells were obtained,and different concentrations of curcumin were added to compare the inhibitory efficiency of different concentrations of curcumin on breast cancer cells.According to the experimental requirements,the MCF⁃7 cells cultured in vitro were divided into the normal control group,group A(curcumin treatment),group B(curcumin+transfection of miR⁃182⁃5p mimics),and group C(curcumin+transfection of PTEN inhibitor BpV+miR⁃182⁃5p inhibitor).The expression levels of PTEN and miR⁃182⁃5p were detected by RT⁃PCR.The expression levels of KI67,Caspase 3,matrix metalloproteinase⁃2(MMP⁃2)and MMP⁃9 proteins related to cell proliferation,apoptosis,metastasis and invasion were detected by Western blot.Results Curcumin treatment for 24 and 48 hours inhibited the proliferation of MCF⁃7 breast cancer cells,and the inhibition rate increased with the increase of curcumin concentration:The inhibition rate was 80μmol/L>60μmol/L>40μmol/L>20μmol/L(F=276.512,255.478,P<0.05).Compared to the normal control group,the expression level of PTEN in groups A,B and C was increased(F=11.536,P<0.05),while the expression level of miR⁃182⁃5p was decreased(F=10.896,P<0.05).Compared to the normal control group,the protein expressions of KI67,MMP⁃2,and MMP⁃9 in groups A,B,and C decreased(F=10.569,10.412,8.210,P<0.05),and the expression of caspase 3 increased(F=11.911,P<0.05).Conclusion Curcumin can inhibit the occurrence and development of breast cancer by regulating the PTEN/miR⁃182⁃5p axis,promoting the expression of the apoptosis factor caspase 3,and inhibiting the expression of proteins related to cell proliferation,metastasis and invasion.