ORIGINAL ABSTRACT

Prostatic acinar adenocarcinomas (PAA) continue to represent a challenge in terms of incidence and efficiency of screening and targeted therapy programs. The capacity of the tumor cell population to renew itself through differentiation and activation of stem cells constitutes a mechanism of tumor protection and survival, but also of acquisition of aggressive phenotypes. In this study, we analyzed CD133 immunoexpression in 55 cases, in relation to the clinico-epidemiological and histopathological parameters of the tumors. CD133 reactions were present at the nuclear and cytoplasmic level and focally membranous in tumor and stromal cells, both from tumor areas and in the case of non-neoplastic tissue. CD133 showed significantly higher reactions in PAA diagnosed in patients in extreme age groups and with elevated serum PSA values. Immunoreactions were significantly higher in some subtypes of PAA (conventional and colloid), in advanced grading groups and with perineural and lymphovascular invasion. In addition to identifying reservoirs of cells with stem potential, CD133 can be used to identify PAA with aggressive behavior, suggesting a biological connection of the two features and the utility for stratifying patients for therapy.