ARHGEF37 and hepatocellular carcinoma: Furthermore, IHC assay revealed that the ARHGEF37 protein level was markedly increased in primary HCC tissues that experienced pulmonary metastasis (n = 30) and further elevated in HCC tissue at metastatic site (n = 30), compared with that in non-metastatic HCC tissues (n = 70) (Fig. 1f and g).