CLGN and hepatocellular carcinoma: The expression of six ERSRGs between HCC and normal tissues was deeply investigated in Fig. 6A. The results showed that there were significantly higher expression levels of CLGN, PPP1R16A and THBS4 and lower expression levels of CTH, SRPX and THBS1 in HCC tissues compared with normal tissues, implying that CLGN, PPP1R16A and THBS4 as oncogenic genes played an important role in HCC development and progression while CTH, SRPX and THBS1 as onco-suppressor genes may play an inhibitory role in HCC.