Proteomic analysis of differential protein expression in human nasopharyngeal carcinoma cells induced by NAG7 transfection

Abstract

Nasopharyngeal carcinoma (NPC) is a commonly occurring tumor in southern China and south east Asia. A genetic factor has now been recognized to be associated with this cancer. A new gene, named NAG7, was cloned from the common minimal deletion region in 3p25.3-26.3. In order to investigate the function of NAG7 gene, proteomic methods were used to find and identify the differential proteins and expected to elucidate the mechanism of NAG7. The NAG7 eukaryotic expression vector was constructed and transfected into NPC cell line HNE1 with liposome. Twenty-two differential protein spots in transfected cells were found significant and reproducible using high-resolution two-dimensional electrophoresis. Nine proteins that were up-regulated and seven proteins that were down-regulated were identified by matrix assisted laser desorption/ionization time of flight mass spectrometry and database analysis. These proteins included growth arrest specific protein, DNA binding protein, caspase 6, pinch protein and ras-related protein rab-36, which are involved in cell cycling, transcription regulation, signaling pathways and apoptosis. NAG7 may exert its functions by mediating differential expression of these proteins.

Serum Protein Profiling to Identify High-Risk Neuroblastoma: Preclinical Relevance of Blood-Based Biomarkers

“…The serum immunoglobulin protein Ig κ-C was found to decrease in mice harboring NB as compared to controls. Surprisingly, aberrant expression of Ig κ-C in cancer cells and tissues has been reported [17,18]. While we did not observe this trend in the present study, further work is needed to clarify the reduction of this serum Ig with regards to NB tumor progression.…”

Tumor suppressor genes on frequently deleted chromosome 3p in nasopharyngeal carcinoma

“…During the last decade, several candidate TSGs at 3p21.3 have been identified and characterized, including RASSF1A [Ras association (RalGDS/AF-6) domain family member 1], GNAT1 [guanine nucleotide binding protein (G protein), alpha transducing activity polypeptide 1], BLU (zinc finger, MYND-type containing 10), and LARS2 (leucyl-tRNA synthetase 2, mitochondrial), which are inactivated by promoter hypermethylation and/or LOH in NPC [36] - [40] . Several other TSGs at 3p have been identified, including NAG7 (long intergenic non-protein coding RNA 312) at 3p25 [41] , LTF (lactotransferrin) at 3p21 [42] , [43] , FBLN2 (fibulin 2), TMEM45A (transmembrane protein 45A), ZIC4 (Zic family member 4), GPR149 (G protein-coupled receptor 149), and ETV5 (ets variant 5) [44] . Recently, in our laboratory, candidate TSGs CACNA2D3 (calcium channel, voltage-dependent, alpha 2/delta subunit 3) at 3p21.1, RBMS3 (RNA-binding motif, single stranded interacting protein 3) at 3p33, and CHL1 [cell adhesion molecule with homology to L1CAM (close homolog of L1)] at 3p26 have been identified (unpublished data) (Table 2).…”

Nasopharyngeal carcinoma: Advances in genomics and molecular genetics

“…Proteomics has also been used to explore the biological functions of novel NPC-associated genes in cellular signaling networks [70]. NGX6 [71,72], NAG7 [73,74], and BRD7 [75,76] are novel genes cloned in our lab. To investigate their function, 2-DE was used to compare the protein expression profiles of NPC and control cell lines transfected with these genes.…”

“…It functions by inhibiting cell cycle progression and promoting apoptosis [132]. We introduced gene chip [133] and proteomic [73] techniques when we studied this gene. We constructed differential gene and protein expression profiles induced by overexpression NAG7 in NPC cells, and found that our identified differentially expressed genes mainly participated in transcriptional regulation, cell growth, the cell cycle, cell metabolism, and apoptosis signaling transduction pathways.…”