TM4SF4 transcript and protein levels were not associated with the clinico-demographical characteristics examined including age, gender, cirrhosis, AFP, and ALT, except lower TM4SF4 transcript expression in stage III-IV compared with stage I-II patients (p = 0.014) but this was not significant at the protein levels (p = 0.477) where median TM4SF4 protein levels were higher in stage III-IV than stage I-II HCC patients (S2 Fig). Here, TM4SF4 is linked to hepatocellular carcinoma.