Purpose: Tumor-infiltrating lymphocytes are considered to represent a host immune response against tumor. This study was carried out to analyze the effect of both FoxP3+ regulatory T cells (Tregs) and CD8+ T lymphocytes in prognostic value of hepatocellular carcinoma (HCC) patients.
Methods: Expressions of FoxP3, CD4, CD8 and CD34 in patient-matched tumors and peritumoral tissues were assessed by immunohistochemistry for 54 HCC patients. The prognostic effect of groups with high and low numbers was evaluated by the Kaplan-Meier and Cox model analysis using median values as a cutoff.
Results: Compared with the corresponding peritumoral tissue, the density of intratumoral Tregs was significantly higher, while the density of intratumoral CD8+ T cells was lower (p < 0.001 and p = 0.013, respectively). In addition, tumor-infiltrating Tregs were positively correlated with microvessel density in tumors (r = 0.334, p = 0.020). The high intratumoral Tregs density group showed a significantly lower survival rate (overall survival, p = 0.018; disease-free survival, p = 0.029). Multivariate Cox analysis revealed that intratumoral Tregs density was an independent prognostic factor for HCC.
Conclusions: Tumor-infiltrating Tregs may promote HCC progression by fostering angiogenesis and decreasing CD8+ T cells. High tumor-infiltrating Tregs are thought to be an unfavorable prognostic indicator for HCC.
Copyright © 2012 S. Karger AG, Basel.