Analysis of the indoleamine 2,3 dioxygenase (IDO) expression in human urinary bladder Carcinoma cells induced to epithelial-mesenchymal transition with TGF-beta1

Abstract

The epithelial-mesenchymal transition process (EMT) in urogenital carcinomas correlates with tumor growth and metastasis. In this process, the cells express mesenchymal markers such as vimentin, acquiring a fusiform phenotype that improves tumoral invasion. The EMT is controlled by specific factors as TGF- ²1 (transforming growth factor-beta). The indoleamine 2,3 dioxygenase (IDO) enzyme is recognized as an immunomodulating factor and is present in several types of tumors, as well as in other tissues, and correlated to the neoplastic progression. Studies on dendritic cells have demonstrated that this enzyme can be induced by TGF-²1 via PI3K signaling pathway, the same pathway that initiates the process of EMT in tumors. The expression of IDO correlates with a worse clinical prognosis, raising the possibility that IDO participates in tumor maintenance. The aim of this study is to analyze the expression of IDO in bladder carcinoma cells (established human lineage, T24) induced to EMT with TGF-beta1 in order to correlate the expression of IDO with markers of EMT. EMT will be analyzed by E-cadherin and vimentin expression, using real-time PCR, the same method for evaluation IDO expression. Results will be expressed as a relative expression from the housekeeping gene TBP (TATA box binding protein). The results of the study may contribute to understanding the role of IDO in the pathophysiology of epithelial tumors. (AU)