川芎嗪抑制缺氧诱导的乳腺癌MDA-MB-435S细胞的侵袭及迁移

Tetramethylpyrazine inhibits hypoxia-induced migration and invasion of breast cancer cell line MDA-MB-435S in vitro

目的 :探讨川芎中的主要成分川芎嗪(tetramethylpyrazine,TMP)对缺氧诱导的乳腺癌细胞MDA-MB-435S迁移及侵袭的影响及可能的作用机制。方法 :构建MDA-MB-435S细胞体外缺氧模型。采用MTT法确定缺氧条件下TMP不影响MDA-MB-435S细胞增殖的浓度;免疫荧光法检测缺氧条件下TMP对MDA-MB-435S细胞形态的影响;应用Transwell小室法和划痕愈合实验观察TMP对缺氧诱导后的MDA-MB-435S细胞侵袭和迁移能力的影响。蛋白质印迹法检测TMP对转录因子缺氧诱导因子1α(hypoxia-inducible factor-1α,HIF-1α)介导的肿瘤转移相关蛋白血管内皮生长因子A(vascular endothelial growth factor-A,VEGF-A)、赖氨酰氧化酶-1(lysyl oxidase-1,LOX-1)、锌指转录因子Snail和Slug表达的影响。结果 :TMP在缺氧条件下可以明显转变MDA-MB-435S细胞的形态,减少F-肌动蛋白(F-actin)应力纤维的数量,并且可以抑制MDA-MB-435S细胞的侵袭和转移能力。初步研究发现,TMP是通过抑制缺氧条件下HIF-1α的蛋白表达,从而减少了HIF-1α转录激活的转移相关靶基因蛋白VEGF-A、LOX-1、Snail和Slug的表达以达到抑制乳腺癌细胞转移的效应。结论 :缺氧条件下TMP能抑制MDA-MB-435S细胞的转移,这可能与其下调HIF-1α及其介导的肿瘤转移相关蛋白的表达有关。TMP对于治疗缺氧诱导的乳腺癌转移具有良好的应用前景。

Objective： To investigate the effect of tetramethylpyrazine（TMP）, a major active component in Chinese medicine Ligusticum chuanxiong, on metastasis of breast cancer cell line MDA-MB-435 S in vitro, and its possible mechanism.Methods： MDA-MB-435 S cells were cultured under hypoxic condition, which could trigger malignant metastatic potential of tumor cells in vitro. Thus, the concentration of TMP which could not affect the proliferaion of hypoxic MDA-MB-435 S cells was determined by MTT assay. The morphology of MDA-MB-435 S cells treated with TMP under hypoxic condition was observed by immunofluorescence. The capacities of invasion and migration of hypoxic MDA-MB-435 S cells were determined by Transwell chamber and Wound healing assays, respectively. The expressions of hypoxia-inducible factor-1α（HIF-1α）-mediated metastasisrelated proteins, such as vascular endothelial growth factor-A（VEGF-A）, lysyl oxidase-1（LOX-1）, Snail and Slug, were detected by Western blotting.Results： TMP could significantly change the morphology and inhibit the metastasis of MDA-MB-435 S cells cultured under hypoxic condition, improve the morphology of the cells, reduce the number of stress fibers of F-actin, and inhibit the capacities of invasion and migration of the cells in vitro. Moreover, TMP reduced the expression levels of HIF-1α–mediated metastasis-related target proteins VEGF-A, LOX-1, Snail and Slug proteins through decreasing the expression of HIF-1α under hypoxic condition, which resulted in the inhibition of metastasis of MDA-MB-435 S cells.Conclusion： These findings indicate that TMP can inhibit the metastasis of breast cancer MDA-MB-435 S cells by reducing the expressions of HIF-1α and the metastasis-related target proteins in vitro. Therefore, TMP may be an effective agent to prevent hypoxia-induced metastasis of breast cancer.