Role of CD26 on oncogenic gene expression

Purpose: Investigate a mechanism of CD26 to promote tumor progression in mesothelioma. Background: CD26 play a role on tumor progression and is expressed in many kinds of human malignancy, including mesothelioma, renal cell carcinoma, and T cell leukemia/lymphoma. In mesothelioma, expression of CD26 is observed in mesothelioma cells, but not in non-neoplastic mesothelioma cells, suggesting a role of CD26 on tumor progression (Clin Cancer Res 13:4191-4200, 2007). CD26 is known to activate T-cells through associating with adenosine deaminase, mannose 6-phosphatic/insulin-like growth factor II receptor, or with CD45RO (Immunol Res 161:55-70, 1998). However, mechanism of CD26 to promote tumor progression was not known. In order to examine a mechanism of CD26 to promote tumor progression in mesothelioma, changes of gene expression profile on CD26-depletion or CD26-overexpression in mesothelioma cells were investigated by microarray analysis. CD26 was depleted by transfection of CD26 siRNA into mesothelioma cell line ACC-MESO1, while CD26 overexpression was conducted by transfecting CD26 into mesothelioma cell line MSTO-211H. Total RNAs were isolated from these cell lines and subjected to microarray analysis.