Prognostic value of HLA class Ⅰ expression in patients with oral squamous cell carcinoma.

Human leukocyte antigen (HLA) class ROMAN NUMERAL ONE molecules play a central role in anticancer immunity, but their prognostic value in oral squamous cell carcinoma (OSCC) remains unclear. We examined HLA class I expression in 2 distinct tumor compartments, namely, the tumor center and invasive front, and evaluated the association between its expression pattern and histopathological status in 137 cases with OSCC. Human leukocyte antigen class ROMAN NUMERAL ONE expression was graded semiquantitatively as high, low, and negative. At the invasive front of the tumor, HLA class I expression was high in 72 cases (52.6%), low in 44 cases (32.1%), and negative in 21 cases (15.3%). The HLA class I expression in the tumor center was high in 48 cases (35.0%), low in 58 cases (42.4%), and negative in 31 cases (22.6%). The 5-year overall survival and disease-specific survival rates were good in cases with high HLA class I expression at the invasive front; however, there was no significant difference in survival based on HLA class I expression in the tumor center. In addition, high HLA class I expression was correlated with high CD8(+) T cell density, whereas negative HLA class I expression was correlated with low CD8(+) T cell density at the invasive front. These results suggest that it is easier for CD8(+) T cells to recognize presented peptides in the case of high HLA class ROMAN NUMERAL ONE expression at the tumor invasive front and could be a prognostic factor for OSCC.