Comparative protein expression in vaginal and cervical squamous cell carcinoma .

Abstract

Objective To identify proteins that are differentially expressed in normal vaginal tissue, vaginal and cervical cancer in order to elucidate relevant cancer-related proteins. Material Sixteen fresh frozen tissue biopsies, consisting of 5 biopsies from normal vaginal epithelium, 6 from primary vaginal carcinomas and 5 from primary cervical carcinomas were analyzed by using two-dimensional gel electrophoresis (2-DE) and MALDI-TOF masspectrometry. Results 43 proteins with significant alterations in the protein expression between non-tumourous and tumourous tissue were identified. 26 and 17 proteins were up- and downregulated respectively. Some were similarly altered in vaginal and cervical carcinoma, for example cytoskeletal proteins, tumour suppressor proteins, oncoproteins implicated in apoptosis and proteins in ubiquitin-proteasome pathway. Three proteins were uniquely altered in vaginal carcinoma (deadbox protein (DDX48), erbB3 binding protein and biliverdin reductase) and six proteins in cervical cancer (peroxiredoxin 2, annexin A2, sarcomeric tropomyosin kappa, human ribonuclease inhibitor and prolyl-4-hydrolase beta). Conclusion The identified proteins indicate involvement of multiple different cellular pathways in the carcinogenesis of vaginal carcinoma. Similar protein alterations were found between vaginal and cervical carcinoma pointing at common tumourigenesis. However the expression level of some of these proteins markedly differs between the three tissue specimens indicating that they might be useful molecular markers