下调的垂体肿瘤转化基因1（PTTG1）表达促进人前列腺癌LNCaP-AI细胞衰老

[Down-regulated PTTG1 expression promotes the senescence of human prostate cancer LNCaP-AI].

作者信息

Wei Yang-Yang, Song Xiao-Ming, Xiong Zhao-Hui, Lu Ke-Quan, Zheng Lu, Cao Xi-Liang

机构信息

Department of Urology, Anhui Armed Police Corps Hospital, Hefei, Anhui 230061, China.

Department of Urology, The 71st Group Army Hospital of the PLA, Xuzhou, Jiangsu 221004, China.

出版信息

Zhonghua Nan Ke Xue. 2019 Mar;25(3):216-222.

PMID:32216239

Abstract

OBJECTIVE

To investigate the effect of the down-regulated expression of pituitary tumor-transforming gene 1 (PTTG1) on the senescence of human castration-resistant prostate cancer LNCaP-AI cells.

METHODS

Human castration-resistant prostate cancer LNCaP-AI cells were induced in vitro and transfected with siRNA targeting PTTG1 (the siRNA-PTTG1 group), the reagent lip3000 only (the mock group) or siRNA negative control vector (the NC group). All the cells were cultured in fetal bovine serum (FBS) or charcoal-stripped bovine serum (CSS) and counted with the cell counting chamber. The senescence characteristics of the transfected LNCaP-AI cells were examined by senescence-associated β-galactosidase (SA-β-Gal) staining, and the expressions of the senescence-related β-galactosidase-1-like proteins (Glb1), the cyclin-dependent kinase inhibitors p-21CIP1 and p-27Kip1, and the chromatin-regulating heterochromatin protein 1γ (HP1γ) were detected by Western blot.

RESULTS

The expression of PTTG1 in the human prostate cancer LNCaP-AI cells was significantly reduced in the siRNA-PTTG1 group compared with those in the mock and NC groups (0.21 ± 0.01 vs 0.56 ± 0.02 and 0.61 ± 0.02, P < 0.05). Culture with FBS markedly increased while that with CSS decreased the number of LNCaP-AI cells transfected with siRNA, but both FBS and CSS enhanced the proliferation of the LNCaP-AI cells in the mock and NC groups. SA-β-Gal staining revealed that reducing the expression of PTTG1 induced a remarkably higher positive rate of the LNCaP-AI cells in the siRNA-PTTG1 than in the mock and NC groups (［63.5 ± 2.35］% vs ［11.3 ± 1.24］% and ［12.4 ± 1.15］%, P < 0.05). The siRNA-PTTG1 group, in comparison with the mock and NC groups, showed a significantly down-regulated expression of PTTG1 (0.21 ± 0.01 vs 0.56 ± 0.02 and 0.61 ± 0.02, P < 0.05), but up-regulated expressions of p-21CIP1 (0.32 ± 0.03 vs 0.20 ± 0.02 and 0.21 ± 0.03, P < 0.05), p-27Kip1 (0.38 ± 0.02 vs 0.20 ± 0.03 and 0.22 ± 0.01, P < 0.05), Glb1 (0.24 ± 0.01 vs 0.13 ± 0.01 and 0.15 ± 0.01, P < 0.05), and HP1γ (0.41 ± 0.01 vs 0.26 ± 0.01 and 0.27 ± 0.02, P < 0.05) in the LNCaP-AI cells.

CONCLUSIONS

Down-regulated expression of PTTG1 induces senescence of human castration-resistant prostate cancer LNCaP-AI cells.

摘要

目的

探讨垂体瘤转化基因1（PTTG1）表达下调对人去势抵抗性前列腺癌LNCaP-AI细胞衰老的影响。

方法

体外诱导人去势抵抗性前列腺癌LNCaP-AI细胞，并分别用靶向PTTG1的小干扰RNA（siRNA）转染（siRNA-PTTG1组）、仅用脂质体3000转染（空载体组）或小干扰RNA阴性对照载体转染（NC组）。所有细胞均在胎牛血清（FBS）或活性炭处理的牛血清（CSS）中培养，并用细胞计数板计数。通过衰老相关β-半乳糖苷酶（SA-β-Gal）染色检测转染后LNCaP-AI细胞的衰老特征，并用蛋白质免疫印迹法检测衰老相关β-半乳糖苷酶-1样蛋白（Glb1）、细胞周期蛋白依赖性激酶抑制剂p-21CIP1和p-27Kip1以及染色质调节异染色质蛋白1γ（HP1γ）的表达。

结果

与空载体组和NC组相比，siRNA-PTTG1组人前列腺癌LNCaP-AI细胞中PTTG1的表达显著降低（0.21±0.01 vs 0.56±0.02和0.61±0.02，P<0.05）。FBS培养显著增加而CSS培养减少了转染siRNA的LNCaP-AI细胞数量，但FBS和CSS均增强了空载体组和NC组LNCaP-AI细胞的增殖。SA-β-Gal染色显示，与空载体组和NC组相比，siRNA-PTTG1组中PTTG1表达降低导致LNCaP-AI细胞的阳性率显著更高（［63.5±2.35］% vs ［11.3±1.24］%和［12.4±1.15］%，P<0.05）。与空载体组和NC组相比，siRNA-PTTG1组LNCaP-AI细胞中PTTG1的表达显著下调（0.21±0.01 vs 0.56±0.02和0.61±0.02，P<0.05），但p-21CIP1（0.32±0.03 vs 0.20±0.02和0.21±0.03，P<0.05）、p-27Kip1（0.38±0.02 vs 0.20±0.03和0.22±0.01，P<0.05）、Glb1（0.24±0.01 vs 0.13±0.01和0.15±0.01，P<0.05）和HP1γ（0.41±0.01 vs 0.26±0.01和0.27±0.02，P<0.05）的表达上调。