Putative Target Proteins Of The Ribosomal Protein, Rpel27 In Nasopharyngeal Carcinoma Cells

The pathogenesis of nasopharyngeal carcinoma (NPC) is multifactorial and multigenic. Despite the identification of several NPC-associated ribosomal proteins (RPs), the roles of these factors and their interacting partners in NPC tumourigenesis are poorly understood. To date, NPC- associated RP genes are either up or down-regulated in diseased/tumour situation compared to normal condition. The ribosomal protein eL27 (RPeL27) has been known to be over-expressed at both transcript and protein levels in NPC cell lines. This hypothesis was reinforced by our study herein. More importantly, using gene knockdown (RNA interference technique) followed by 2D gelelectrophoresis (2D GE) and in silico analysis; we revealed 15 proteins that are likely to interact with RPeL27 during situation of NPC tumourigenesis. These include COTL1, MAGOHB, UBE2N, NDPKA, TMED10, PSMB6, CA2, PGAM1, RPeL14, RPeS8, TPI1,PSMA2, RPeL19, GSTP1, and TPM1. Their association with RPeL27 could attribute to gene expression alteration, cell migration disruption and invasion, promotion of cancer cell survival, immune evasion, and genomic instability. Our findings provide new theoretical insights into the mechanism and involvement of RPeL27 in NPC pathogenesis. This is pertinent in understanding the molecular pathogenesis mediated by ribosomal proteins in the malignancy of the nasopharyngeal tissues

Identification and Characterization of Proteins in Association with Ribosomal Protein, eL27 in Nasopharyngeal Carcinoma Cells

Ribosomal proteins (RPs) were only believed to involve in ribosome biogenesis and protein synthesis but there are increasing evidences to show the potential extraribosomal functions of ribosomal proteins. Ribosomal proteins are involved in regulation of cellular cell growth and differentiation as many studies have linked cancers to the differential expression of RPs. The ribosomal protein, eL27 has shown significant differential expression in cell lines derived from nasopharyngeal carcinoma (NPC) as compared to normal nasopharyngeal epithelium at both transcript and protein level. However, the protein-interacting partners of RPeL27 in NPC remains largely unknown. Hence, in this study we identified and characterized the proteins affected by RPeL27-knockdown in NPC via siRNA knockdown, 2-Dimensional Gel Electrophoresis (2D GE), liquid chromatography mass spectrometry (LCMS) and bioinformatics analysis. We successfully identified 15 differentially expressed proteins in RPeL27-knockdown HK1 cells and all the 15 proteins are cancer-related, often dysregulated in various diseases and take part in significant biological processes responsible for proper cell growth and proliferation. Therefore, the overexpression of RPeL27 could be responsible for NPC development and progression through association with 15 proteins identified either directly or indirectly. We predicted the possible protein interactions between RPeL27 and the 15 proteins identified via in silico approach. Our findings reinforce the potential role of ribosomal protein L27 in the carcinogenesis of NPC and provided the possible protein interactions between RPeL27 and 15 proteins

Sequence analysis of the ribosomal protein gene, RPS15 in cell line derived from human colorectal carcinoma

Colorectal carcinoma (CRC) is a progressive cancer that is likely to be related with the changes in the gene expression in CRC due to sequence changes. In the recent finding on the human ribosomal protein gene, RPS15 has shown to be upregulated in nasopharyngeal carcinoma (NPC) and human hepatocellular carcinoma (HPC) tumor cells compared to the normal cells but no studies have been done in studying the RPS15 gene in CRC. The objective of this study is to carry out sequence analysis of RPS15 gene in CRC cell line, HCT116. The starting materials were the total RNA from HCT116 and transcribed into cDNA by using Moloney Murine Leukemia Virus Reverse Transcriptase (M-MLV RT). The cDNA was then successfully amplified by the polymerase chain reaction (PCR) and proceed with sequence analysis. The sequence of RPS15 from HCT116 showed high similarity of 99 % and conservation with the reference sequence of RPS15 at the National Centre for Bioinformatics (NCBI) website for both nucleotide and protein sequence. In addition, RPS15 gene encodes two biological significant sites, which are protein kinase C phosphorylation and N-myristoylation site. This finding suggests RPS15 gene is highly conserved in HCT116 and encodes for two biological important sites