Dissimilar immunohistochemical expression of ERK and AKT between paired biopsy and hepatectomy tissues of hepatocellular carcinoma

Background/Aim: Biomarker studies using immunohistochemical (IHC) staining have not been successful for advanced hepatocellular carcinoma (HCC). We aimed to examine whether the tissue procurement process influences the protein expression levels detected by IHC. Materials and Methods: Forty-two tissue pairs of HCC that had been both preoperatively biopsied and then surgically resected were included in the study. IHC staining was used to determine expression of target molecules, all of which were graded according to the percentage of positively stained tumor cells. The expression of beta-catenin was analyzed according to the localization of positive staining. Results: Biopsied and surgically resected tissues exhibited dissimilar phosphorylated extracellular signal regulated kinase (p-ERK) and phosphorylated AKT expression levels (kappa=0.025 and 0.153, respectively). On the contrary, p53 exhibited similar expression levels, and beta-catenin exhibited similar staining localization patterns in biopsied and surgically resected tissues (kappa=0.729 and 0.654, respectively). Conclusion: Biopsied HCC tissues and their corresponding resected HCC tissues have inconsistent IHC-detected ERK and AKT expressions.