Gong Tuotuo, Zheng Shuyu, Huang Shan, Fu Shenbo, Zhang Xuanwei, Pan Shupei, Yang Tian, Sun Yuchen, Wang Ya, Hui Beina, Guo Jia, Zhang Xiaozhi
Department of Radiation Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an Shaanxi Province, China.
Department of Radiation Oncology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an Shaanxi Province, China.
Mol Carcinog. 2017 Dec;56(12):2610-2619. doi: 10.1002/mc.22705. Epub 2017 Aug 21.
PTEN pseudogene (PTENP1) has a tumor suppressive role in multiple cancers. However, its involvement in esophageal squamous cell carcinoma (ESCC) remains largely unknown. In this study, we set out to identify the role of PTENP1 in the development of ESCC. Gene Expression Omnibus database was employed to investigate the expression of PTENP1 in ESCC. sRNA target Database (StarBase v2.0) was used to query the downstream of PTENP1. Next, both in vitro and in vivo experiments were employed to explore the function. Cell proliferation was evaluated by CCK-8, soft agar, and colony formation assays. Expression of relative genes was assessed by quantitative real-time PCR (qRT-PCR) and Western blotting. 3'UTR luciferase assay was used to confirm the miRNA binding. The clinical significance of PTENP1 was further validated by immunohistochemistry (IHC) and correlation with clinicopathological indicators in additional samples (n = 93). We found expression of PTENP1 in ESCC was lower than that in the corresponding adjacent normal tissues (n = 17). Overexpression of PTENP1 in Eca109 and TE-1 cells resulted in inhibited proliferation and altered expression of SOCS6-p-STAT3-HIF-1α pathway both in vitro and in vivo. Subsequent IHC reported a similar trend in human ESCC samples. 3'UTR luciferase assay demonstrated that PTENP1 3'UTR decoyed miR-17-5p from binding to SOCS6. Moreover, PTENP1 expression was correlated with clinicopathological indicators to varying degrees, including histological grade, TNM stage, infiltration depth, lymph node metastasis, and overall survival. Taken together, these results suggested an anti-oncogenic role of PTENP1. Meanwhile, PTENP1 may also serve as a candidate of prognostic indicator for ESCC patients.
PTEN假基因（PTENP1）在多种癌症中具有肿瘤抑制作用。然而，其在食管鳞状细胞癌（ESCC）中的作用仍 largely未知。在本研究中，我们着手确定PTENP1在ESCC发生发展中的作用。利用基因表达综合数据库研究PTENP1在ESCC中的表达。使用小RNA靶标数据库（StarBase v2.0）查询PTENP1的下游靶点。接下来，通过体外和体内实验来探究其功能。通过CCK-8、软琼脂和集落形成实验评估细胞增殖。通过定量实时PCR（qRT-PCR）和蛋白质免疫印迹法评估相关基因的表达。使用3'UTR荧光素酶实验来确认miRNA结合。通过免疫组织化学（IHC）以及与另外93例样本的临床病理指标的相关性，进一步验证PTENP1的临床意义。我们发现ESCC中PTENP1的表达低于相应的癌旁正常组织（n = 17）。在Eca109和TE-1细胞中过表达PTENP1导致体外和体内细胞增殖受到抑制，且SOCS6-p-STAT3-HIF-1α信号通路的表达发生改变。随后的免疫组织化学结果显示在人类ESCC样本中也有类似趋势。3'UTR荧光素酶实验表明PTENP1的3'UTR可诱骗miR-17-5p不与SOCS6结合。此外，PTENP1的表达与组织学分级、TNM分期、浸润深度、淋巴结转移和总生存期等多种临床病理指标不同程度相关。综上所述，这些结果提示PTENP1具有抑癌作用。同时，PTENP1也可能作为ESCC患者预后指标的候选分子。
