26 - Role of Immunohistochemical Expression of Aminopeptidases in Ovarian Carcinoma

This chapter discusses the expression and localization of the aminopeptidases in ovarian tumor, by immunohistochemical analysis, and on expression patterns related to neoplastic transformation, differentiation, and histologic type. The presence and function of cell-surface aminopeptidases in carcinoma cells are described in the chapter. Cell-surface aminopeptidases, such as neutral endopeptidase (NEP/CD 10), insulin-regulated aminopeptidase (IRAP/P-LAP), and dipeptidyl peptidase IV (DPPIV/ CD10), degrade a variety of peptide factors and hormones and influence many cellular functions. The expression of NEP and DPPIV seems negatively related to the degree of malignant potential of the carcinoma cells. However, the high expression of P-LAP and acyl peroxy nitrates (APN) is reported in highly malignant endometrial and pancreatic carcinoma. Because these aminopeptidases degrade several peptide factors, their functions may vary in different types of carcinoma and tissue. It is very important to know, whether certain molecules are present or absent in target tissues and cells, because the nature of carcinoma cell lines changes from that of their original tissues or cells during long-term culture. The IHC method is a convenient and important method of demonstrating the presence and localization of certain molecules.