Wang Xiaohai, Xu Yongzhi, Wang Xingjie, Jiang Chenyi, Han Sha, Dong Kai, Shen Mengjun, Xu Dongliang
Department of Urology, Shanghai General Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200080, China.
Cell Prolif. 2017 Dec;50(6). doi: 10.1111/cpr.12395. Epub 2017 Oct 9.
Previously, we found that long intergenic non-coding RNA-p21 (lincRNA-p21) inhibited the development of human prostate cancer. However, the underlying molecular mechanisms are poorly understood. Here, we attempted to investigate the downstream targets of lincRNA-p21 in prostate cancer.
Expression of lincRNA-p21 and PKM2 was determined by qRT-PCR and Western blot. Lentivirus expressing shPKM2 or shCtrl was used to explore the role of PKM2 on the enhanced cell proliferation and glycolysis of lincRNA-p21-silenced prostate cancer cells. A xenograft mouse model was performed to investigate the effect of PKM2 suppression, glycolytic or mammalian target of rapamycin (mTOR) inhibitor on the tumorigenic capacity of lincRNA-p21-silenced prostate cancer cells.
We revealed that lincRNA-p21 silencing in DU145 and LNCaP cells induced up-regulation of PKM2 and activation of glycolysis, which could be reversed by PKM2 knockdown or rapamycin treatment. We also found that the proliferation and tumorigenesis of lincRNA-p21-silenced prostate cancer cells were significantly inhibited after knocking down PKM2. 3-bromopyruvate (3-Brpa) or rapamycin treatment largely decreased the tumour burden. Importantly, PKM2 expression was inversely correlated with the lincRNA-p21 level and the survival of prostate cancer patients.
We demonstrated that lincRNA-p21 blunted the prostate cancer cell proliferation and tumorigenic capacity through down-regulation of PKM2. Therefore, targeting PKM2 or glycolysis might be a therapeutic strategy in prostate cancer patients with lowly expressed lincRNA-p21.
此前，我们发现长链基因间非编码RNA-p21（lincRNA-p21）可抑制人类前列腺癌的发展。然而，其潜在的分子机制尚不清楚。在此，我们试图研究前列腺癌中lincRNA-p21的下游靶点。
通过qRT-PCR和蛋白质免疫印迹法检测lincRNA-p21和丙酮酸激酶M2（PKM2）的表达。使用表达shPKM2或shCtrl的慢病毒来探究PKM2对lincRNA-p21沉默的前列腺癌细胞增强的细胞增殖和糖酵解的作用。建立异种移植小鼠模型，以研究抑制PKM2、糖酵解或雷帕霉素哺乳动物靶点（mTOR）抑制剂对lincRNA-p21沉默的前列腺癌细胞致瘤能力的影响。
我们发现，在DU145和LNCaP细胞中沉默lincRNA-p21可诱导PKM2上调和糖酵解激活，而PKM2敲低或雷帕霉素处理可逆转这种情况。我们还发现，敲低PKM2后，lincRNA-p21沉默的前列腺癌细胞的增殖和肿瘤发生受到显著抑制。3-溴丙酮酸（3-Brpa）或雷帕霉素处理可大大减轻肿瘤负担。重要的是，PKM2表达与lincRNA-p21水平及前列腺癌患者的生存率呈负相关。
我们证明lincRNA-p21通过下调PKM2来抑制前列腺癌细胞的增殖和致瘤能力。因此，针对PKM2或糖酵解可能是lincRNA-p21低表达的前列腺癌患者的一种治疗策略。
