Authors: Changhua Zhuo Ye Xu Mingang Ying Qingguo Li Liyong Huang Dawei Li Sanjun Cai Bin Li
Publish Date: 2015/01/22
Volume: 61, Issue: 3, Pages: 338-347
Abstract
The tumor microenvironment composites a mixture of immune lymphoid cells myeloid cells stromal cells with complex cytokines as well as numerous lymphovascular vessels Colorectal cancer CRC is a common malignancy and one of the leading causes of tumorrelated death in the United States and worldwide The immune status in the tumor microenvironment contributes to the survival of a patient with CRC Regulatory T cells Tregs are considered a key factor in immune escape and immunotherapy failure among cancer patients The transcription factor forkhead box P3 FOXP3 is a crucial intracellular marker and also a key developmental and functional factor for CD4+CD25+ Tregs Tregs are correlated with survival in various human neoplasms and elevated proportions of Tregs are usually associated with unfavorable clinical outcomes However the role of Tregs in CRC remains controversial High densities of tumorinfiltrating Tregs in CRC patients are reported to be correlated with worse or better outcomes And Tregs may not be predictive of prognosis after resection of the primary tumor The exact explanations for these discordant results remain unclear The heterogeneous instincts of cell phenotype gene expression and functional activities of Tregs may partly contribute this contrasting result Furthermore the lack of a robust marker for identifying Tregs or due to the different techniques applied is also account The Tregspecific demethylated region TSDR was recently reported to be a specific epigenetic marker for natural Tregs nTregs which can stably express FOXP3 The FOXP3TSDR demethylation assay may be an promising technique for CRCrelated nTregs studies
Keywords: