MICA and hepatocellular carcinoma: Kohga et al. demonstrated that a disintegrin and metalloproteinase 9 (ADAM9) were overexpressed in human HCC tissues, while ADAM9 knockdown increased the expression of membrane-bound MHC class I-related chain A (MICA), decreased the production of soluble MICA, and increased the sensitivity of human HCC cells to natural killer (NK) cells.