Ribosomal protein L34 promotes the proliferation, invasion and metastasis of pancreatic cancer cells

// Feng Wei 1 , Lijuan Ding 1 , Zhentong Wei 4 , Yandong Zhang 1 , Yang Li 1 , Luo Qinghua 2 , Yuteng Ma 1 , Liang Guo 5 , Guoyue Lv 1 , Yan Liu 2, 3 1 Department of Hepatobiliary & Pancreas Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China 2 Genetic Engineering Laboratory of PLA, The Eleventh Institute of Academy of Military Medical Sciences of PLA, Jilin 130122, P.R. China 3 Department of Pathophysiology, Basic College of Medicine, Jilin University, Changchun, Jilin 130021, P.R. China 4 Oncologic Gynecology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China 5 Pathology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China Correspondence to: Yan Liu, email: liu820512@163.com Guoyue Lv, email: lg08@sina.com Keywords: RPL34, pancreatic cancer, MAPK, metastasis, ingenuity pathway analysis Received: April 27, 2016     Accepted: October 19, 2016     Published: November 10, 2016 ABSTRACT Ribosomal proteins (RPs) are the main components of ribosomes and participate in the self-assembly of ribosomes and protein synthesis. Recent advance has shown that RPs play important roles in the tumorigenesis and drug resistance of various cancers. However, the expression status and function of RPL34 in pancreatic cancer (PC) remains unclear. In this study, we find that RPL34 is overexpressed in PC tissues and cell lines, which is correlated with decreased methylation of its promoter. Knockdown of RPL34 effectively suppresses the proliferation, colony formation, migration and drug-resistance of PC cells, which are accompanied by cell cycle arrest at the G2 phase and induction of apoptosis. In vivo assays demonstrate that RPL34 silencing inhibits PC tumor growth and metastasis. Moreover, gene expression profiling revealed that RPL34 silencing results in alteration of the MAPK and p53 signaling pathways. Clinically, our data indicate a positive association of RPL34 expression with tumor stage and metastasis in PCs. We revealed that RPL34 acts as a potential onco-protein in PC, and RPL34 may be a promising biomarker for prognosis prediction and a potential target for the treatment of PC.