姜黄素联合卡铂对乳腺癌MCF-7细胞放疗增敏作用的实验研究

Sensitization effect of curcumin combined with carboplatin on radiotherapy of breast cancer MCF-7 cells in vitro

目的探讨姜黄素联合卡铂对乳腺癌MCF-7细胞放疗敏感性的影响及其潜在的分子机制。方法体外培养乳腺癌MCF-7细胞,经4 Gy的X射线照射后,分为四组:对照组、卡铂组、姜黄素组、联合组,分别采用二甲基亚矾(DMSO)、卡铂、姜黄素及卡铂联合姜黄素培养48 h,采用四唑氮蓝(MTT)实验和流式细胞仪分别检测MCF-7细胞增殖和凋亡,实时荧光定量PCR(qRT-PCR)检测MCF-7细胞中增殖细胞核抗原(PCNA)、B细胞淋巴瘤/白血病-2(Bcl-2)及Bcl-2相关X蛋白(Bax)mRNA表达情况,Western blot法检测MCF-7细胞中PCNA、Bcl-2、Bax蛋白的表达情况。结果联合组MCF-7细胞增殖率显著低于对照组、卡铂组和姜黄素组(P均<0.05)。联合组MCF-7细胞凋亡率显著高于对照组、卡铂组和姜黄素组(P均<0.05)。联合组MCF-7细胞中PCNA、Bcl-2 mRNA及蛋白表达水平显著低于对照组、卡铂组和姜黄素组(P均<0.05);联合组MCF-7细胞中Bax mRNA及蛋白表达水平显著高于对照组、卡铂组和姜黄素组(P均<0.05)。结论姜黄素和卡铂联合治疗能够增加乳腺癌细胞的放疗敏感性,推测可能通过抑制乳腺癌细胞PCNA、Bcl-2的表达,促进Bax的表达而实现。

Objective To explore the sensitization effect of curcumin combined with carboplatin on the radiosensitivity of breast cancer MCF-7 cells and its potential molecular mechanism. Methods Human breast cancer cell line MCF-7 cells were cultured in vitro. The MCF-7 cells were divided into four groups after 4 Gy X-ray radiation： control group,carboplatin group,curcumin group and combined group. They were cultured in dimethyl sulfoxide（ DMSO）,carboplatin,curcumin,carboplatin plus curcumin for 48 hours,respectively. MTT assay and flow cytometry were used to respectively detect the proliferation and apoptosis of MCF-7 cells. qRT-PCR was used to detect expressions of proliferating cell nuclear antigen（ PCNA）,B-cell lymphoma/lewkmia-2（ Bcl-2） and Bcl-2 associated X protein（ Bax） mRNAs in MCF-7 cells. Western blot was used to detect expressions of PCNA,Bcl-2 and Bax proteins in MCF-7 cells. Results The proliferation rate of MCF-7 cells in combined group was significantly lower than that in control group,carboplatin group and curcumin group（ all P〈0. 05）. The apoptosis rate of MCF-7 cells in combined group was significantly higher than that in control group,carboplatin group and curcumin group（ all P〈0. 05）. The expression levels of PCNA and Bcl-2 mRNAs and proteins in MCF-7 cells in combined group were significantly lower than those in control group,carboplatin group and curcumin group（ all P〈0. 05）. The expression levels of Bax mRNA and protein in MCF-7 cells in combined group were significantly higher than those in control group,carboplatin group and curcumin group（ all P〈0. 05）. Conclusions The combination therapy of curcumin and carboplatin can increase the sensitivity of breast cancer cells to radiotherapy. It is supposed that this effect is achieved by inhibiting the expression of PCNA and Bcl-2 and promoting the expression of Bax in breast cancer cells.