Role of E-cadherin, alpha-, beta-, and gamma-catenins, and p120 (cell adhesion molecules) in prolactinoma behavior

Mod Pathol. 2002 Dec;15(12):1357-65. doi: 10.1097/01.MP.0000039572.75188.1A.

Abstract

E-cadherin/catenin complex regulates cellular adhesion and motility and is believed to function as an invasion suppressor system. In a number of cancers, abnormal and reduced expression of E-cadherin/catenin complex is associated with tumor invasion and metastasis. Prolactinomas show frequent invasion on the surrounding structures, despite their histologically benign nature. Furthermore, gender-based differences in endocrine and surgical findings are found in patients with prolactinoma. To understand biological factors governing prolactinoma behavior, this study analyzed the expression of E-cadherin; alpha-, beta-, and gamma-catenins; p120; and cell proliferation marker MIB-1 labeling index in 13 invasive tumors (9 in men, 4 in women), 26 noninvasive tumors (4 in men, 22 in women), and 8 normal anterior pituitaries by immunohistochemistry. Immunostaining of E-cadherin; alpha-, beta-, and gamma-catenins; and p120 showed a membranous pattern of reactivity and generally stronger in normal pituitaries than in prolactinomas. Expression of E-cadherin and beta-catenin was significantly lower in invasive than in noninvasive prolactinomas (P <.002 and P <.005, respectively), and reduced expression of E-cadherin and beta-catenin was more frequent in invasive than in noninvasive prolactinomas (P <.001 and P <.05, respectively); in contrast, gamma-catenin expression showed higher in invasive than in noninvasive prolactinomas (P <.05). Expression of E-cadherin was significantly lower in macroprolactinomas than in microprolactinomas (P <.01), and decreased expression of E-cadherin and beta-catenin predicted high MIB-1 expression (P <.05). Moreover, the expression of E-cadherin and beta-catenin was significantly lower in macroprolactinomas in men than in those in women (P <.01 and P <.02, respectively). No statistical correlations were observed between expression of alpha-catenin, p120, and clinicopathologic features. In conclusion, the reduction of E-cadherin and beta-catenin expression was related to invasiveness and proliferative status of prolactinomas and correlated with the more aggressive behavior of prolactinomas in men compared with in women.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Cadherins / analysis
  • Catenins
  • Cell Adhesion Molecules / analysis*
  • Cell Adhesion Molecules / physiology
  • Cytoskeletal Proteins / analysis
  • Desmoplakins
  • Female
  • Humans
  • Immunohistochemistry
  • Ki-67 Antigen / analysis
  • Male
  • Middle Aged
  • Phosphoproteins / analysis
  • Pituitary Neoplasms / metabolism
  • Pituitary Neoplasms / pathology*
  • Prolactinoma / metabolism
  • Prolactinoma / pathology*
  • Trans-Activators / analysis
  • alpha Catenin
  • beta Catenin
  • gamma Catenin

Substances

  • CTNNA1 protein, human
  • CTNNB1 protein, human
  • Cadherins
  • Catenins
  • Cell Adhesion Molecules
  • Cytoskeletal Proteins
  • Desmoplakins
  • JUP protein, human
  • Ki-67 Antigen
  • Phosphoproteins
  • Trans-Activators
  • alpha Catenin
  • beta Catenin
  • delta catenin
  • gamma Catenin