Abstract 3759: Discordance of the immunohistochemical expression of phospho-Akt and phosphor-ERK between paired biopsy and hepatectomy specimens of hepatocellular carcinoma

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC Background: Immunohistochemical (IHC) staining using archival tumor tissues is commonly used to study biomarkers of hepatocellular carcinoma (HCC). However, there are no biomarkers proven to be useful for personalized therapy of HCC so far. Since HCC is particularly susceptible to ischemia during and after the operation, the study sought to clarify the consistency of the IHC expression between biopsied and surgically resected HCC tissues. Methods: HCC patients who had both biopsy and hepatectomy tumor tissues were enrolled. IHC staining was done with rabbit antibodies (Cell Signaling, Beverly, MA, US.) against p-Akt (Ser473) and p-ERK1/2 (Thr202/Tyr204). The staining and its evaluation were performed by a pathologist who was blinded to the identification of the slides. The expression levels of both proteins were graded according to the percentage of positively stained cells in every section, as follows: negative: 0%; 1+: 1-10%; 2+: 10-50%, and 3+: > 50%. Staining results of biopsy and hepatectomy tissues were compared. Results: Forty-six tissue pairs were enrolled. The results of IHC staining were shown in the table. The expression was significantly decreased in hepatectomy tissues compared to biopsied tissue for both p-Akt and p-ERK (p < 0.001 and p < 0.001, respectively, by paired t test). The correlation of IHC staining results of paired tissues is poor. Spearman correlation coefficients for p-Akt (r = 0.116) and p-ERK (r = 0.112) were low. If using staining results as a continuous variable in analysis, the correlation between paired tissues remained poor, with Pearson correlation coefficients of 0.418 for p-Akt and 0.219 for p-ERK, respectively. Conclusions: The consistency of p-Akt and p-ERK IHC staining between preoperative biopsy and hepatectomy HCC tissues is poor. This confounding factor should be taken into account in data for biomarkers of HCC. (The study was supported by the grant of NSC 98-3112-B-002-038.) View this table: IHC staining results of p-Akt and p-ERK Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3759.