Research Article The uS8, uS4, eS31, and uL14 Ribosomal Protein Genes Are Dysregulated in Nasopharyngeal Carcinoma Cell Lines Edmund Ui-Hang Sim, 1 Kher-Lee Ng, 1 Choon-Weng Lee, 2 and Kumaran Narayanan 3,4 1 Department of Molecular Biology, Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia 2 Institute of Biological Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia 3 School of Science, Monash University, Bandar Sunway, 46150 Selangor, Malaysia 4 Department of Genetics and Genomics Sciences, Mount Sinai School of Medicine, New York, NY 10029, USA Correspondence should be addressed to Edmund Ui-Hang Sim; uhsim@unimas.my Received 4 May 2017; Accepted 14 June 2017; Published 16 July 2017 Academic Editor: Clara Crescioli Copyright © 2017 Edmund Ui-Hang Sim et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Te association of ribosomal proteins with carcinogenesis of nasopharyngeal carcinoma (NPC) has been established in a limited subset of ribosomal protein genes. To date, three ribosomal protein genes, eL27 (L27), eL41 (L41), and eL43 (L37a), have been found to be diferentially expressed in cell lines derived from NPC tumors. Tis raises the possibility of more ribosomal protein genes that could be associated with NPC. In this study, we investigated the expression profles of eight ribosomal protein genes, uS8 (S8), uS4 (S9), eS31 (S27a), eL6 (L6), eL18 (L18), uL14 (L23), eL24 (L24), and eL30 (L30), in six NPC-derived cell lines ( HONE-1, SUNE1, HK1, TW01, TW04, and C666-1). Teir expression levels were compared with that of a nonmalignant nasopharyngeal epithelial cell line (NP69) using quantitative real-time PCR (RT-qPCR) assay. Of the eight genes studied, the expressions of four ribosomal protein genes uS8 (S8), uS4 (S9), eS31 (S27a), and uL14 (L23) were found to be signifcantly downregulated in NPC cell lines relative to NP69. Our fndings provide novel empirical evidence of these four ribosomal protein genes as NPC-associated genetic factors and reinforce the relevance of ribosomal proteins in the carcinogenesis of nasopharyngeal cancer. 1. Introduction Nasopharyngeal carcinoma (NPC) is a distinct malignant form of head and neck cancer that originates from the lateral or posterosuperior mucosal epithelium of the pharynx. Te World Health Organization (WHO) classifes NPC as three major histopathologic types: Type I, keratinizing squamous cell carcinoma; Type IIa, nonkeratinizing diferentiated cell carcinoma; and Type IIb, nonkeratinizing undiferentiated carcinoma. Type IIb is the most common and contributes to 60% and 95% of NPC cases in North America and Southern China, respectively, and is associated with Epstein-Barr virus (EBV) infection [1]. Global incidence shows a pattern associ- ated with geographical location, where the highest prevalence is among the Chinese population in Southeast Asia and Southern China [2]. Although the involvement of genetic fac- tors in NPC carcinogenesis is widely known, the mechanisms of their infuence and/or action in the disease are not fully understood. Tis could be largely due to the fact that the full range of NPC-associated genes is still unclear. Among some of these are the ribosomal protein (RP) genes. Te products of RP genes canonically function as major components of ribosomes during protein biosynthesis. How- ever, in 1996, Wool [3] listed more than 30 potential extrari- bosomal functions of RPs that include apoptosis, DNA repair, RNA processing, and transcription regulation. Sequence mutation and diferential expression of several ribosomal protein genes have been reported in many human congenital disorders and carcinomas. For instance, more than 200 distinct mutations in nine RP genes, namely, eS19 (S19), eS24 (S24), eS17 (S17), eS7 (S7), eS10 (S10), eS26 (S26), uL18 (L5), uL5 (L11), and eL33 (L35a), were identifed in a majority of Diamond-Blackfan Anemia (DBA) cases [4–10]. Genetic lesions in eL22 (L22) that include heterozygous deletion and Hindawi BioMed Research International Volume 2017, Article ID 4876954, 8 pages https://doi.org/10.1155/2017/4876954