Abstract

This study is about proteomic analysis of oral verrucous carcinoma (OVC). The total proteins obtained from tumour and adjacent normal oral mucosa of patients with OVC and oral squamous cell carcinoma (OSCC) were separated with two dimensional electrophoresis (2-DE) by using immobilized pH gradient strips and visualized by staining with silver nitrate. The gel images were acquired by scanner and 2-DE analysed by image master 2D elite. Twenty distinct protein spots were excised from gel randomly and digested in gel by TPCK-trypsin. Mass analysis of the tryptic digested peptides mixture was performed by using MALDI-TOF-MS. Peptide mass fingerprints (PMFs) obtained by the MALDI-TOF analysis were applied to National Center for Biotechnology Information (NCBI), SWISS-PROT and MSDB databases using Mascot software. Then the 2-DE gel imaging showed that 74, 36 and 31 differential protein spots were found between OVC and OSCC, OVC and adjacent normal oral mucosa of OVC (OVCN), OSCC and adjacent normal oral mucosa of OSCC (OSCCN) samples, respectively. By identification of protein spots from 2-DE gels, 20 PMF maps were obtained by MALDI-TOF-MS including recoverin (cancer associated retinopathy (CAR) protein) tumor protein D53 (hD53), zinc finger protein 77 (ZNFpT1) and so on and these protein may play a key role in the carcinogenesis of OVC and OSCC.

Key words: Oral verrucous carcinoma, oral squamous cell carcinoma, two-dimensional electrophoresis, peptide mass fingerprints, matrix-assisted laser desorption/ionization-time of flight mass spectrometry.

Abbreviation

OVC, Oral verrucous carcinoma; OSCC, oral squamous cell carcinoma; SDS, sodium dodecyl sulphate; TFA, trifluoroacetic acid; DTT,dithiothreitol; IPG, immobiline pH-gradient; PBS, phosphate buffered saline; DTE, 1, 4-dithioerythritol; NCBI, National Center for Biotechnology Information; CAR,Cancer associated retinopathy; IEF, isoelectric focusing