Objective: To investigate the effect and mechanism of PPAR-γ agonist Pioglitazone (PGZ) on the proliferation of malignant mesothelioma (MM) cells. Methods: In December 2019, MM cell lines MSTO-211H and NCI-H2452 were incubated with different final concentrations of PGZ (0, 10, 50, 100, 150, and 200 μmol/L) for different periods of time (24 h, 48 h, and 72 h) , and then the cell proliferation level was detected by CCK8 assay. After given various final concentration of PGZ (0, 10, 50, 100, 150, 200 μmol/L) the for 72 hours, the changes of number and morphology of MM cells were observed under an inverted microscope. The expressions of PPAR-γ and HMGB1 mRNA were determined by real-time fluorescence quantitative reverse transcription-polymerase chain reaction (qRT-PCR) after treatment of MM cells with PGZ of 0, 10, 50, 100 μmol/L for 72 h. The MM cells were treated with PGZ at concentration of 0, 100 μmol/L for 72 h, and the protein expressions of HMGB1 were examined using Western blotting and immunofluorescence; the protein expressions of Ki67 were assessed by immunohistochemistry. Results: The cell viability rate of MM cells was decreased after treated with PGZ (P<0.05) . Cell number in PGZ-treated group was significantly less than that in control group and morphology changes were observed under light microscope. QRT-PCR results revealed significantly increased PPAR-γ mRNA expression in the PGZ-treated group compared to the control group (P<0.05) . There was a significant decrease in the mRNA expression level of HMGB1 in the PGZ-treated group (100 μmol/L) as compared to the control group in MSTO-211H (P<0.05) ; however, the expression level of HMGB1 in NCI-H2452 was an increase or no significant differences (P>0.05) . Western blotting and immunofluorescence results showed that the protein expression of HMGB1 was reduced in the PGZ-treated group compared with the control group in MSTO-211H (P<0.05) , but the protein expression of that in NCI-H2452 was no significant differences (P>0.05) . Immunohistochemistry results showed increased expression of proliferation marker Ki-67. Conclusion: Pioglitazone suppresses the proliferation of MM cells through inhibition of HMGB1 by the activation of PPAR-γ.
目的： 探讨PPAR-γ激动剂吡格列酮（piglitazone，PGZ）对恶性间皮瘤细胞增殖活力的影响及其作用机制。 方法： 于2019年12月，选择人双相型恶性间皮瘤细胞株（MSTO-211H）和人上皮型恶性间皮瘤细胞株（NCI-H2452），给予不同终浓度的PGZ（0、10、50、100、150、200 μmol/L）处理24、48、72 h后，采用CCK8法检测细胞增殖活力，在倒置显微镜下观察细胞数量及形态的变化，实时荧光定量反转录聚合酶链反应（qRT-PCR）检测0、10、50、100 μmol/L PGZ处理细胞72 h时，细胞内PPAR-γ、高迁移率族蛋白B1（HMGB1）mRNA的表达水平；免疫印迹法和免疫荧光法检测0、100 μmol/L PGZ处理细胞72 h时细胞内HMGB1蛋白表达水平，并采用免疫组化法检测肿瘤增殖标志物Ki67蛋白的表达水平。 结果： PGZ处理细胞后，培养24 h后，与对照组比较，100、150、200 μmol/L PGZ处理组MSTO-211H细胞及150、200 μmol/L PGZ处理组NCI-H2452细胞存活率明显下降，差异有统计学意义（P<0.05）。在光镜下可见，与对照组比较，处理组恶性间皮瘤细胞明显减少，形态发生变化。qRT-PCR结果显示，与对照组比较，PGZ处理组PPAR-γ mRNA表达水平上升（P<0.05）；MSTO-211H细胞中100 μmol/L PGZ处理组的HMGB1 mRNA表达水平下降（P<0.05），而NCI-H2452细胞处理组HMGB1 mRNA表达水平上升或无明显变化（P>0.05）。免疫印迹和免疫荧光结果均显示，与对照组比较，MSTO-211H细胞PGZ处理组中HMGB1蛋白表达水平下降（P<0.05），NCI-H2452细胞中HMGB1蛋白表达无明显变化（P>0.05）。免疫组化结果显示，给予PGZ处理后恶性间皮瘤细胞内肿瘤增殖标志物Ki67的表达水平下降。 结论： PGZ可能通过激活PPAR-γ抑制HMGB1的表达从而抑制恶性间皮瘤细胞的增殖活力。.
Keywords: High mobility group box-1; Malignant mesothelioma; Pioglitazone; peroxisome proliferators-activated receptor-γ.