Virchows Archiv. 2012 Nov 28. [Epub ahead of print] [Link]
Mogi A, Koga K, Aoki M, Hamasaki M, Uesugi N, Iwasaki A, Shirakusa T, Tamura K, Nabeshima K.
Department of Pathology, Fukuoka University School of Medicine and Hospital, 7-45-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180, Japan.
Malignant cells supply their energy needs through increased glucose consumption, producing large quantities of lactic acid via glycolysis. Glucose transporters (GLUTs) and monocarboxylate transporters (MCTs) are therefore commonly up-regulated in human malignancies to mediate glucose influx and lactic acid efflux, respectively. However, their roles in malignant pleural mesothelioma (MPM) have not been fully elucidated. Here, we evaluated GLUT-1, MCT-1, and MCT-4 expression in human MPM and reactive mesothelial hyperplasia (RMH) and elucidated their biological role in vitro. GLUT-1, MCT-1, and MCT-4 expression was determined in human MPM (nâ€‰=â€‰35) and RMH (nâ€‰=â€‰20) specimens by immunohistochemistry and in frozen tissue, and MPM cell lines, by real-time reverse transcription-polymerase chain reaction and western blot analysis. GLUT-1, MCT-1, and MCT-4 functions in MPM were evaluated by transfection with small interfering RNA. Immunohistochemical analysis revealed higher levels of GLUT-1, MCT-1, and MCT-4 in MPM than in RMH. Additionally, GLUT-1, MCT-1, and MCT-4 mRNA levels were higher in MPM than in non-neoplastic mesothelial cell lines. The siRNA-mediated knockdown of GLUT-1 or MCT-1 significantly suppressed tumor cell proliferation, and MCT-1 silencing inhibited invasion and induced apoptosis. Taken together, these results indicate that combined application of GLUT-1, MCT-1, and MCT-4 immunohistochemistry might be useful in differentiating MPM from RMH and suggest that MCT-1plays an important biological role.