The long non-coding RNA PTTG3P promotes cell growth and metastasis via up-regulating PTTG1 and activating PI3K/AKT signaling in hepatocellular carcinoma

• DOI: 10.1186/s12943-018-0841-x
• Publication Date: 2018-05-26T06:39:26Z
• Authors: Jin-lan Huang; Shun-wang Cao; Qi-shui Ou; Bin Yang; Shi-hao Zheng; Jing Tang; Jing Chen; Yan-wei Hu; Lei Zheng; Qian Wang
• Keywords: Male; Carcinoma, Hepatocellular; PTTG1; Mice; Phosphatidylinositol 3-Kinases; 03 medical and health sciences; Cell Line, Tumor; Animals; Humans; Neoplasm Metastasis; PTTG3P; RC254-282; Cell Proliferation; 0303 health sciences; Research; Liver Neoplasms; Neoplasms. Tumors. Oncology. Including cancer and carcinogens; Hepatocellular Carcinoma; Hep G2 Cells; Prognosis; Survival Analysis; 3. Good health; Gene Expression Regulation, Neoplastic; Securin; Long non-coding RNA; Female; RNA, Long Noncoding; PI3K/AKT signaling; Proto-Oncogene Proteins c-akt; Neoplasm Transplantation; Signal Transduction

Dysfunctions of long non-coding RNA (lncRNAs) have been associated with the initiation and progression of hepatocellular carcinoma (HCC), but the clinicopathologic significance and potential role of lncRNA PTTG3P (pituitary tumor-transforming 3, pseudogene) in HCC remains largely unknown.We compared the expression profiles of lncRNAs in 3 HCC tumor tissues and adjacent non-tumor tissues by microarrays. In situ hybridization (ISH) and quantitative real-time polymerase chain reaction (qRT-PCR) were applied to assess the level of PTTG3P and prognostic values of PTTG3P were assayed in two HCC cohorts (n = 46 and 90). Artificial modulation of PTTG3P (down- and over-expression) was performed to explore the role of PTTG3P in tumor growth and metastasis in vitro and in vivo. Involvement of PTTG1 (pituitary tumor-transforming 1), PI3K/AKT signaling and its downstream signals were validated by qRT-PCR and western blot.We found that PTTG3P was frequently up-regulated in HCC and its level was positively correlated to tumor size, TNM stage and poor survival of patients with HCC. Enforced expression of PTTG3P significantly promoted cell proliferation, migration, and invasion in vitro, as well as tumorigenesis and metastasis in vivo. Conversely, PTTG3P knockdown had opposite effects. Mechanistically, over-expression of PTTG3P up-regulated PTTG1, activated PI3K/AKT signaling and its downstream signals including cell cycle progression, cell apoptosis and epithelial-mesenchymal transition (EMT)-associated genes.Our findings suggest that PTTG3P, a valuable marker of HCC prognosis, promotes tumor growth and metastasis via up-regulating PTTG1 and activating PI3K/AKT signaling in HCC and might represent a potential target for gene-based therapy.