CLEC4M and lung cancer: CLEC4M was successfully knocked down in the human lung cancer cell lines A549 and H1299 (Figure 2A, 2B, 2E and 2F); we also observed a remarkable increase in CLEC4M expression at both the mRNA and protein levels, which demonstrated that CLECM was successfully overexpressed (Figure 2C, 2D, 2G and 2H).