LRRK2在乳腺癌细胞增殖和耐药中的作用及其机制研究

目的:探讨LRRK2在乳腺癌组织中的表达及其对乳腺癌细胞增殖、凋亡及耐药的作用和分子机制.方法:采用实时荧光定量PCR(qRT-PCR)和Western blot检测了48例乳腺癌组织及其配对正常组织中LRRK2表达;并检测人正常乳腺上皮细胞MCF-10A、乳腺癌细胞株MCF-7、MDA-MB-231、BT-483及阿...

Effects of LRRK2 on proliferation and drug resistance of breast cancer cells

Objective:To investigate the expression of LRRK2 in breast cancer and its effect and molecular mechanism on the proliferation,apoptosis and drug resistance of breast cancer cells.Methods:Quantitative real-time PCR(qRT-PCR)and Western blot were used to detect the expression of LRRK2 in 48 breast cancer tissues and their matched normal tissues.The mRNA and protein expression levels of LRRK2 in human normal breast epithelial cells MCF-10A,breast cancer cell lines MCF-7,MDA-MB-231,BT-483,and adriamycin resistant cell lines MCF-7/ADR were detected.LRRK2 expression was interfered by transfection of si-LRRK2 sequence.CCK-8 assay and flow cytometry were used to detect the effect of knockdown LRRK2 on the proliferation activity,IC₅₀value and apoptosis of MCF-7 and MCF-7/ADR cells,respectively.The expressions of apoptosis-related proteins,drug-resistant proteins and proteins related to TLR4/NF-κB signaling pathway were detected by western blot.Results:The expression of LRRK2 in breast cancer tissues and cells was significantly higher than that in adjacent normal tissues and normal breast epithelial cells(P<0.01).Compared with the blank control group and negative control siRNA group,the proliferation activity of MCF-7 and MCF-7/ADR cells in si-LRRK2 group was significantly inhibited,the apoptosis rate and the expression of apoptosis-related proteins Caspase-3 and Bax were significantly increased,and the expression of Bcl-2 was significantly decreased(P<0.01).The IC₅₀value of MCF-7/ADR cells and the expression of drug-resistant protein P-gp in si-LRRK2 group were significantly decreased(P<0.01),and the sensitivity of MCF-7/ADR cells to chemotherapy was significantly increased.In si-LRRK2 group,the levels of TLR4/NF-κB pathway related proteins TLR4,NF-κB p65,p-IKKβand p-IκB phosphorylation were significantly decreased(P<0.01),and the expression of inflammasome NLRP3 was also significantly decreased(P<0.01).pcDNA3.1-TLR4 or pcDNA3.1-NLRP3 were co-transfected with si-LRRK2 group,and the inhibitory effect of LRRK2 on the proliferation and drug resistance of MCF-7/ADR cells and the pro-apoptotic effect of LRRK2 were significantly reversed(P<0.05).Conclusion:LRRK2 is highly expressed in breast cancer tissues and cells,and knockdown of LRRK2 can inhibit the proliferation of breast cancer cells,induce cell apoptosis,and improve the sensitivity of drug-resistant cells to chemotherapy.LRRK2 may regulate P-gp expression by regulating TLR4/NF-κB signaling pathway and NLRP3 inflammasome,activate NLRP3 mediated inflammation pathway,participate in the biological behavior of breast cancer cells,and delay cell drug resistance.