Expression of autophagy-related protein beclin-1 in malignant canine mammary tumors
Journal
BMC Veterinary Research
Journal Volume
9
Date Issued
2013
Author(s)
Abstract
Background: Autophagy is a self-catabolic mechanism that degrades unnecessary cellular components through lysosomal enzymes. Beclin-1, an autophagy-related protein, establishes the first connection between autophagy and tumorigenesis. The purpose of this study is to assess the Beclin-1 expression pattern and to determine its prognostic significance in patients with malignant canine mammary tumor (CMT). Results: We examined Beclin-1 expression in 70 cases of malignant CMTs by immunohistochemistry. Cytoplasmic Beclin-1 expression was significantly weaker in cancer cells than in nearby normal mammary glands (p < 0.001). Low cytoplasmic expression (57.14%) was associated with older age, lower degree of tubular formation, increased mitotic activity, higher histologic grade, and extensive necrosis. Low nuclear expression (40%) was connected with older age, lower degree of tubular formation, extensive necrosis, and negative for Her2/neu overexpression. Univariate survival analysis showed that Beclin-1 cytoplasmic expression was a poor prognostic factor for overall survival rate (p < 0.001). Multivariate survival analysis demonstrated that Beclin-1 cytoplasmic expression is an independent prognostic factor (p = 0.016).Conclusions: Loss of Beclin-1 is associated with aggressive clinicopathologic features and poor overall survival. The results suggest that Beclin-1 plays an important role in tumor progression of malignant CMTs. ? 2013 Liu et al.; licensee BioMed Central Ltd.
Subjects
Autophagy; Beclin-1; Canine mammary tumor; Immunohistochemistry
SDGs
Other Subjects
apoptosis regulatory protein; apoptosis regulatory protein; age; animal; carcinoma; dog; Dog Diseases; female; Mammary Neoplasms, Animal; metabolism; pathology; prognosis; sarcoma; survival; udder; veterinary; animal disease; article; dog disease; experimental mammary neoplasm; metabolism; Age Factors; Animals; Apoptosis Regulatory Proteins; Carcinoma; Dog Diseases; Dogs; Female; Mammary Glands, Animal; Mammary Neoplasms, Animal; Prognosis; Sarcoma; Survival Analysis; Age Factors; Animals; Apoptosis Regulatory Proteins; Carcinoma; Dog Diseases; Dogs; Female; Mammary Glands, Animal; Mammary Neoplasms, Animal; Prognosis; Sarcoma; Survival Analysis
Type
journal article