These data indicate that Gab2 mediates the pathologic progression of HCC by integrating multiple signaling pathways and suggest that Gab2 might be a powerful therapeutic target for HCC.—Cheng, J., Zhong, Y., Chen, S., Sun, Y., Huang, L., Kang, Y., Chen, B., Chen, G., Wang, F., Tian, Y., Liu, W., Feng, G.-S., Lu, Z. Gab2 mediates hepatocellular carcinogenesis by integrating multiple signaling pathways. Here, GAB2 is linked to hepatocellular carcinoma.