SRC激酶抑制剂PP2 通过上调Cx43蛋白表达降低肺癌A549 细胞的侵袭和转移

目的观察SRC激酶抑制剂PP2对肺癌细胞A549侵袭转移能力的影响，并探讨相关机制。方法采用MTT法检测PP2对A549细胞的增殖抑制作用；利用细胞划痕实验和Transwell 实验分别测定不同浓度PP2处理A549细胞24 h后的侵袭和转移能力；采用Western blot法检测SiRNA沉默Cx43基因、mRNA过表达Cx43基因和PP2处理后细胞内Cx43、MMP-2的表达。结果MTT法显示2、4、8、16、32 μmol/L PP2显著抑制A549细胞的增殖，且在该范围内有浓度依赖性。采用1、2、4、8、16 μmol/L PP2分别作用于A549细胞24 h，细胞的侵袭、转移能力也逐渐降低（P<0.05）。4 μmol/L 和8 μmol/L PP2可以显著增加细胞Cx43蛋白水平，降低MMP-2蛋白水平。过表达Cx43蛋白后，PP2抑制细胞侵袭转移能力增强；沉默Cx43蛋白后，PP2抑制细胞侵袭转移能力降低（P<0.05）。结论SRC激酶抑制剂PP2可以降低肺癌细胞A549的侵袭转移能力，该作用与细胞Cx43蛋白的表达有关。

SRC kinase inhibitor PP2 inhibits invasion and metastasis of lung cancer A549 cells byupregulating connexin43 expression

Objective To investigate the effect of SRC kinase inhibitor PP2 on the invasion and metastasis of lung cancer A549cells and explore its molecular mechanism. Methods MTT assay was used to evaluate the inhibitory effect of PP2 on theproliferation of A549 cells. Cell scratch and Transwell assays were performed to assess the invasion and metastatic capacity ofA549 cells after treatment with 1, 2, 4, 8, and 16 μmol/L PP2 for 24 h. Western blotting was used to detect the expressions ofconnexin43 (Cx43) and MMP-2 in the cells after small interfering RNA (siRNA)-mediated silencing or overexpression of Cx43;the changes in the cell invasion and metastasis in response to PP2 treatment after Cx43 silencing or overexpression wereinvestigated. Results MTT assay showed that treatment with PP2 at 2, 4, 8, 16, and 32 μmol/L significantly inhibited theproliferation of A549 cells in a concentration-dependent manner. Treatments with PP2 at 1, 2, 4, 8, and 16 μmol/L for 24 h alsoconcentration-dependently lowered the invasion and metastatic abilities of the cells (P<0.05). At 4 and 8 μmol/L, PP2significantly increased the expression level of Cx43 protein and decreased the expression level of MMP-2 protein.Overexpression of Cx43 significantly enhanced the inhibitory effect of PP2 on the cell invasion and metastasis, and Cx43silencing significantly attenuated the inhibitory effect of PP2 (P<0.05). Conclusions PP2 treatment can suppress the invasionand metastasis of A549 cells in vitro possibly by modulating the expression of Cx43.