CD163 and leukoplakia: By detecting the expression of M1 marker CD86 and M2 marker CD163, we observed a significant increase in the frequency of CD86+ cells in the macrophages pre-treated with CM from SCC25 and Cal27 compared to CM from HIOEC and Leuk1 (Fig. 1b), indicating that the THP-1-derived macrophages exhibited an M1-like phenotype when treated with CM from OSCC cells but not CM from normal epithelium or leukoplakia cells.