Overexpression of EpCAM and Trop2 in pituitary adenomas

We sought to investigate the expression of EpCAM and Trop2 in Pituitary adenomas (PAs) and study the correlation of protein expression with invasiveness, proliferation, clinical functioning, recurrence/progression, and some other factors. We investigated the expression of EpCAM and Trop2 in 74 samples of PAs by immunohistochemistry and made correlative analysis of protein overexpression with clinicopathological parameters. Follow-up data was analyzed for recurrence/progression with Kaplan-Meier method and Multivariate Cox regression analysis. Immunohistochemistry results showed that overexpression rates of EpCAM and Trop2 were 51/74 (68.9%) and 43/74 (58.1%), respectively. For both EpCAM and Trop2, PAs with invasiveness showed a higher overexpression rate than PAs without invasiveness (PEpCAM = 0.001; PTrop2 = 0.006). Nonfunctional Pituitary adenomas (NFPAs) demonstrated a higher EpCAM overexpression than functional Pituitary adenomas (FPAs) (P = 0.026). Both EpCAM and Trop2 overexpression correlated significantly with expression of proliferation factor Ki-67 (PEpCAM = 0.011; PTrop2 = 0.000), but not with gender and age. Follow-up analysis revealed that Trop2 overexpression was a significantly predictive factor for recurrence/progression by means of Kaplan-Meier method d (P = 0.028) and Multivariate Cox regression analysis (P = 0.025). This study reveals that both EpCAM and Trop2 overexpression in PAs correlate significantly with invasiveness and proliferation. EpCAM presents a potential target for differential diagnosis and immunotherapy for NFPAs. Follow-up analysis shows that Trop2 is a predictive factor for recurrence/progression for PAs.