厚朴酚通过PD-1/PD-L1通路介导非小细胞肺癌增殖和凋亡的机制研究

Study on mechanism of magnolol mediating proliferation and apoptosis of non-small cell lung cancer through PD-1/PD-L1 pathway

目的探讨厚朴酚对非小细胞肺癌(non-small cell lung cancer,NSCLC)增殖和凋亡的影响及其具体机制。方法收集西安交通大学第二附属医院NSCLC组织标本30例以及对应的癌旁组织,通过real-time RT-PCR和Western blot检测组织中PD-1以及PD-L1的表达水平。将肺癌细胞A549分为对照组(厚朴酚0μmol/L)、低剂量厚朴酚(40μmol/L)组和高剂量厚朴酚(80μmol/L)组,通过RT-PCR和Western blot检测厚朴酚对PD-L1表达的影响,MTT法检测厚朴酚对细胞增殖的影响,并通过流式细胞仪检测厚朴酚对细胞凋亡的影响。结果PD-1 mRNA、PD-L1 mRNA及蛋白的表达水平在肺癌组织中高于癌旁组织,差异具有统计学意义(P<0.05)。PD-L1 mRNA和蛋白的表达水平在低剂量厚朴酚组和高剂量厚朴酚组均低于对照组(P<0.05);低剂量厚朴酚组和高剂量厚朴酚组间PD-L1的表达比较,差异无统计学意义(P>0.05)。MTT法结果显示,低剂量和高剂量厚朴酚组在48 h和72 h时肺癌细胞A549的吸光度值明显低于对照组(P<0.05)。流式细胞术检测结果显示,与对照组比较,低剂量和高剂量厚朴酚组凋亡率均升高(P<0.05),低剂量厚朴酚组和高剂量厚朴酚组间差异无统计学意义(P>0.05)。结论厚朴酚可以下调肺癌细胞A549中PD-L1的表达,抑制肺癌细胞增殖并促进凋亡,从而发挥其抗肿瘤的作用。

Objective To investigate the effect of magnolol on the proliferation and apoptosis of non-small cell lung cancer(NSCLC)and its mechanism.Methods Thirty NSCLC tissue specimens and the corresponding adjacent tissues from the Second Affiliated Hospital of Xi’an Jiaotong University were collected.The expression levels of PD-1 and PD-L1 in tissues were detected by RT-PCR and Western blot.A549 lung cancer cells were divided into control group(0μmol/L magnolol),low-dose magnolol group(40μmol/L)and high-dose magnolol group(80μmol/L).The expression of PD-L1 in A549 cells was detected by RT-PCR and Western blot,the proliferation of A549 cells was detected by MTT method,and the apoptosis of A549 cells was detected by flow cytometry.Results The expression levels of PD-1 mRNA,PD-L1 mRNA and protein in lung cancer tissues were higher than those in adjacent tissues(P<0.05).The expression levels of PD-L1 mRNA and protein in low-dose magnolol group and high-dose magnolol group were statistically lower than those in control group(P<0.05).There was no significant difference in the expression of PD-L1 between low-dose magnolol group and high-dose magnolol group(P>0.05).MTT results showed that the absorbance of lung cancer cell A549 in low-dose magnolol group and high-dose magnolol group was significantly lower than that in control group at 48 h and 72 h(P<0.05).Flow cytometry results showed that compared with control group,the apoptosis rate was increased in low-dose group and high-dose group(P<0.05),while there was no significant difference between low-dose magnolol group and high-dose magnolol group(P>0.05).Conclusion Magnolol can down-regulate the expression of PD-L1 in lung cancer cell line A549,inhibit the proliferation and promote the apoptosis of lung cancer cell line A549,thereby exerting its anti-tumor effect.