TREM2 and hepatocellular carcinoma: To detect the function of TREM2 in HCC progression, we established stable TREM2 knockdown and overexpression clones in MHCC97L cells (with a lower lung metastasis rate of 40%) and MHCC97H cells (with a higher lung metastasis rate of 100%), respectively, both of which were established from one parent HCC cell line23.