Editorial
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Dec 7, 2006; 12(45): 7233-7238
Published online Dec 7, 2006. doi: 10.3748/wjg.v12.i45.7233
Colon cancer and the immune system: The role of tumor invading T cells
Maximilian Waldner, Carl C Schimanski, Markus F Neurath
Maximilian Waldner, Carl C Schimanski, Markus F Neurath, I. Department of Medicine, University of Mainz, Mainz, Germany
Correspondence to: Professor Markus F Neurath, MD, I. Department of Medicine, University of Mainz, Langenbeckstrasse 1, Mainz 55131, Germany. neurath@1-med.klinik.uni-mainz.de
Telephone: +49-6131-177104  Fax: +49-6131-175595
Received: July 18, 2006
Revised: July 28, 2006
Accepted: September 20, 2006
Published online: December 7, 2006
Abstract

Colon cancer is still one of the leading causes of cancer death worldwide. Although the host immune system has been shown to react against tumor cells, mainly through tumor infiltrating lymphocytes and NK cells, tumor cells may utilize different ways to escape anti-tumor immune response. Tumor infiltration of CD8+ and CD4+ (T-bet+) effector T cells has been attributed to a beneficial outcome, and the enhancement of T cell activation through T cell receptor stimulation and co-stimulatory signals provides promising strategies for immunotherapy of colon cancer. Growing evidence supports a role for the Fas/FasL system in tumor immunology, although the mechanisms and consequences of FasL activation in colon cancer are not completely understood. In animal models, depletion of regulatory T cells (CD4+ CD25+ T cells) can enhance the anti-tumor immune response under certain conditions. Taken together, recent insights in the immune reaction against colon carcinoma have provided new approaches to immunotherapy, although much remains to be learned about the exact mechanisms.

Keywords: CD4-positive T-lymphocytes; CD8-positive T-lymphocytes; Immunology; Colonic neoplasms therapy; Colorectal neoplasms; Humans; Lymphocytes; Tumor-infiltrating; Tumor escape