Expression of Toll-like receptor 4 in ovarian serous adenocarcinoma and correlation with clinical stage and pathological grade.

Toll-like receptor 4 (TLR4) plays an essential role in adaptive and innate immunity, and its expression has been described in various tumors. This study aimed to examine the expression of TLR4 in serous tumors and to evaluate its correlation to clinicopathological parameters. The expression of TLR4 was immunohistochemically examined in 63 species of normal ovarian epithelia and 336 species of serous epithelial lesions. Moreover, the association between TLR4 expression and various clinicopathologic features was assessed. The expression intensity of TLR4 in benign and borderline to malignant ovarian tumours showed a gradual rising trend. We identified positive correlations between TLR4 expression levels and both FIGO stage and pathological stage. In serous adenocarcinoma, TLR4 expression levels were significantly associated with chemoresistance. There was no relationship between the expression of TLR4 and the patient's age or pretreatment serum CA125 levels. Our data suggest that TLR4 might stimulate serous ovarian carcinoma initiation and progression. TLR4 expression is correlated with poor chemoresponse, which has important implications for the development of new therapeutic strategies for drug-resistant ovarian cancer.