Glypican 3 Expression in Urothelial Carcinoma: A Histopathological and Immunohistochemical Study

Introduction: Glypican 3 (GPC3) is an oncofetal protein, playing a role in cell regulation during fetal development, via Wingless/Integration (Wnt) signaling pathway. GPC3 immunohistochemical expression was detected in several tumours, most obvious in hepatocellular carcinoma. The GPC3 antibody is under clinical trials for the therapeutic approach of hepatocellular carcinoma. Aim: Correlation of glypican 3 expression in urothelial carcinoma with clinicopathological features, to detect its possible role in stimulating Wnt signaling which is supposed to be responsible for urothelial carcinogenesis, where GPC3 can be used as a future therapeutic target. Materials and Methods: This retrospective study included a total of 125 archived, formalin fixed, paraffin embedded tissue blocks of 125 cases of UC, including 90 cases of radical cystectomies with high-grade UC and 35 cases of Transurethral Resection of Bladder Tumour (TURT) with low-grade UC. The samples were immunohistochemically analysed for GPC3 expression. Results: A statistically significant correlation was detected between GPC3 expression and tumour (T) stage (p-value=0.047). Conclusion: GPC3 has a partial role in urothelial carcinogenesis. Further studies are needed to investigate the possible role of GPC3 in differentiation between low and high-grade UC. Also, GPC3 may differentiate between neoplastic and non-neoplastic urothelial tissue.