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目的:探讨重组肿瘤抑素T42肽对人肝癌干细胞(LCSCs)恶性表型的影响及作用机制。方法:2018年6月至2019年6月，培养人肝癌细胞系SMMC-7721，利用免疫磁珠法富集CD133n ＋肝癌干细胞LCSCs。实验共分3组：正常组、T42肽(40 mmol/L)处理组和5-氟尿嘧啶(40 mmol/L)处理组。通过细胞计数试剂盒(CCK-8)检测处理后第1、2、3、4天的细胞活力；克隆形成实验检测3组细胞处理后第14天的克隆形成情况；流式细胞术检测3组LCSCs处理24 h后的细胞凋亡率；Transwell实验分别检测3组LCSCs处理48 h后的迁移和侵袭能力；蛋白质印迹法(Western blot)检测3个不同处理组细胞中凋亡相关蛋白B细胞淋巴瘤/白血病-2(bcl-2)、bcl-2相关X蛋白(bax)、剪切型含半胱氨酰天冬氨酸特异性蛋白酶3(Cl-Caspase-3)、E-钙黏蛋白(E-cadherin)、波形蛋白(Vimentin)、基质金属蛋白酶(MMP)-2、MMP-9等的表达。符合正态分布的组间比较采用n t检验，不符合正态分布的采用单因素方差分析。n 结果:T42肽、5-氟尿嘧啶处理组LCSCs的克隆形成率[(41.67±8.26)%、(52.03±10.35)%]、细胞迁移数[(97.17±13.73)、(111.51±8.60)个]和细胞侵袭数[(79.02±7.87)、(86.03±6.54)个]显著低于对照组[(98.67±7.37)%、(185.67±12.88)个、(139.83±18.32)个]，凋亡率[(13.21±0.38)%、(9.02±0.35)%]显著高于对照组[(4.07±0.38)%]，差异均有统计学意义(n t＝12.613、8.991；11.513、11.732；7.472、6.781；41.503、23.412，n P值均<0.05)。Western blot结果显示T42肽、5-氟尿嘧啶通过增加bax和Cl-Caspase-3，抑制bcl-2的蛋白表达来诱导LCSCs凋亡，通过上调E-cadherin同时下调Vimentin、MMP-2和MMP-9的表达水平来调节LCSCs的迁移和侵袭。n 结论:T42肽具有抑制LCSCs的增殖、迁移、侵袭，并促进其凋亡的作用。“,”Objective:To investigate the effect and mechanism of recombinant tumstatin T42 peptide on malignant phenotype of human liver cancer stem cells (LCSCs). WT5" HZ]Methods:From June 2018 to December 2019, human hepatoma cell line SMMC-7721 purchased from Shanghai Cell Bank of Chinese Academy of Sciences was cultured. cluster of differentiation 133(CD133)n + LCSCs were enriched by immunomagnetic beads. The experiment was divided into three groups: normal group, T42 peptide (40 mmol/L) treatment group and 5-fluorouracil (40 mmol/L) treatment group. The cell viability was detected by cell counting kit-8 (CCK-8) assay on day 1, 2, 3 and 4 after treatment and the colony formation of the three groups of cells was measured at 14th day after treatment. The apoptosis rate of the three groups was tested by flow cytometry after 24 h of treatment. The migration and invasion ability of the three LCSCs groups after 48 h of treatment were examined by Transwell test. The expression levels of B cell lymphoma/leukemia-2 (bcl-2), bcl-2 associated X protein (bax), Cl-cysteinyl aspartate-specific protease (Caspase)-3, E-cadherin, vimentin, matrix metalloproteinase (MMP)-2 and MMP-9 were detected by Western blotting.n Results:As compared with the control group [(98.67±7.37)%, (185.67±12.88), (139.83±18.32), (4.07±0.38)%], the clone formation rate [(41.67±8.26)%, (52.03±10.35)%], number of migrating cells [(97.17±13.73), (111.51±8.60)] and number of invading cells [(79.02±7.87), (86.03±6.54)] in the T42 peptide and 5-fluorouracil treated groups were significantly decreased, while the apoptosis rate [(13.21±0.38) %, (9.02±0.35)%] was increased significantly (n t=12.613, 8.991; 11.513, 11.732; 7.472, 6.781; 41.503, 23.412; all n P<0.05). Western blotting results showed that T42 peptide and 5-fluorouracil induced apoptosis of LCSCs by increasing bax and Cl-Caspase-3 and inhibiting the protein expression of bcl-2. The migration and invasion of LCSCs were regulated by up-regulating E-cadherin and down-regulating the expression of vimentin, MMP-2 and MMP-9.n Conclusion:T42 peptide can inhibit the proliferation, migration and invasion of LCSCs and promote apoptosis.