Clinicopathological findings in relation to beclin-1 protein expression among patients with Juvenile/Hamartomatous Polyps

Abstract

Background Juvenile or hamartomatous polyps represent the most common pediatric polyps. Although neoplastic transformation in juvenile polyps is uncommon, dysplastic alterations were observed. The role of autophagy in hamartomatous lesions remains unclear. Objectives To assess the relationship between clinicopathological changes and beclin-1 protein expression among patients with juvenile/hamartomatous polyps. Patients and methods A total of 134 patients were enrolled in a case–control study: 63 cases of juvenile polyps, 59 colonic tissues as controls, and 12 colonic adenomas. All colonic tissues were subjected to immunohistochemistry testing of the beclin-1 protein. In juvenile polyps, the expression of beclin 1 was associated with available clinicopathological characteristics as well as the expression of SMAD family member 4 (SMAD4) and platelet-derived growth factor receptor (PDGFR). Results One-third of juvenile polyps exhibited indefinite dysplastic changes. Beclin-1 shows significantly lower expression in juvenile polyps compared with controls ( P =0.002). There was a trend of high beclin-1 expression in juvenile polyp/indefinite dysplasia compared with their counterpart lacking dysplasia ( P =0.066). Beclin-1 expression did not significantly differ between adenomatous and juvenile polyp/indefinite dysplasia groups ( P =0.28). Loss of beclin-1 expression was associated with lower SMAD4 and PDGFR expression ( P =0.002 and P =0.001, respectively). Conclusions Beclin-1 expression is low in juvenile polyps, which could be dependent on SMAD4 and PDGFR expression. When compared with cases with indefinite dysplasia and adenomas, beclin-1 loss in juvenile polyps could be an early sign of neoplastic changes.