Relationship and clinical significance of TGF-beta1 expression with Treg cell infiltration in hepatocellular carcinoma / 癌症

ABSTRACT

<p><b>BACKGROUND AND OBJECTIVE</b>There are few studies about origins of regulatory T (Treg) cells increased in primary hepatocellular carcinoma (HCC) tissue. Studies showed that Treg cells could be induced by transforming growth factor-beta1 (TGF-beta1), but the relation between TGF-beta1 expression and Treg cell infiltration is unclear in HCC tissue. This study was to investigate the expression of TGF-beta1 and correlations with the amount of Treg cells in HCC, and to evaluate their clinical values in predicting the prognosis of HCC.</p><p><b>METHODS</b>Envision immunohistochemistry was used to detect the expression of TGF-beta1 and Foxp3 in 102 specimens of HCC tissue and paired adjacent non-tumor liver tissue.</p><p><b>RESULTS</b>Of the 102 specimens of HCC, 41 showed low TGF-beta1 expression and 61 (59.8%) showed high expression; of the 102 specimens of adjacent non-tumor tissue, 22 showed low TGF-beta1 expression and 80 (78.4%) showed high expression. The high expression rate of TGF-beta1 was significantly lower in HCC than in adjacent non-tumor tissues (P = 0.001). Average Foxp3+ cell density in HCC was 2.98 cells/HP, but there was very few or no expression of Foxp3 in adjacent non-tumor liver tissue. Expression of TGF-beta1 was positively correlated with expression of Foxp3 in HCC tissues (r = 0.228, P = 0.021). The expression of TGF-beta1 was significantly higher in HCC tissues with high preoperative AFP concentration than in those with low preoperative AFP concentration (P = 0.023). TGF-beta1 and Foxp3 expression had no correlations with tumor diameter, tumor capsule, liver cirrhosis, and so on. The 5-year survival rate was not different between HCC tissues with high and low TGF-beta1 expression (P = 0.790); however, it was significantly lower in HCC tissues with high Treg cell infiltration than in those low infiltration (25% vs. 44%, P = 0.007). Cox multivariate analysis showed that the number of Treg cells and tumor capsule were independent prognostic factors (P = 0.021, P = 0.001).</p><p><b>CONCLUSIONS</b>Expression of TGF-beta1 may relate to the infiltration of Treg cells in HCC tissues, but the relation need to be further investigated. The number of Treg cells in HCC tissues could be used as a potential immunological prognostic indicator for HCC patients after resection.</p>