ERBB2 and hepatocellular carcinoma: Furthermore, our results showed that the average copy number of chromosome 17 centromere (CEP17) was significantly higher in tumor tissues than in matched nontumor tissues (3.55 ± 1.99 versus 2.07 ± 0.22, P < 0.01), but the gains of CEP17 in HCC were not associated with HER2 overexpression.