Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

INTRODUCTION: Autophagy enables cells to recycle long-lived proteins or damaged organelles. Beclin 1, the mammalian orthologue of the yeast Apg6/Vps30 gene, functions as a scaffold for the formation of autophagosomes. MATERIALS AND METHOD: The immunohistochemical patterns of Beclin 1 expression and their prognostic relevance were studied in formalin-fixed tissues from 155 patients with colorectal adenocarcinoma treated with surgery alone. RESULTS: Using the weak homogeneous expression of Beclin 1 in normal colonic tissues as a basis for assessing tumours, the following grouping/staining patterns were recognised in colorectal carcinomas: a normal-like pattern in 62 of 155 (40%) cases, an underexpression pattern in 24 of 155 (15.5%) cases, extensive overexpression of Beclin 1 in 33 of 155 (21.3%) tumours and limited overexpression of the protein in 36 of 155 (23.2%) tumours. Extensive overexpression of Beclin 1 was significantly linked with overexpression of HIF1α and LDH5, as well as with high histological grade, vascular invasion and nodal involvement. Furthermore, patients with extensive over- or underexpression of Beclin 1 had a significantly poorer overall survival compared with the other two groups (P<0.0001). Beclin 1 had an independent prognostic relevance in multivariate analysis. CONCLUSIONS: Beclin 1 has an important role in growth and metastasis of colorectal cancer. Loss of Beclin 1 expression (allelic loss or microRNA regulatory activity, as suggested in the literature) defines poor prognosis presumably by promoting anti-apoptotic pathways, while overexpression of the protein, being linked with tumour hypoxia and acidity, also defines subgroups of tumours with aggressive clinical behaviour.

Original publication

DOI

10.1038/sj.bjc.6605904

Type

Journal article

Journal

Br j cancer

Publication Date

12/10/2010

Volume

103

Pages

1209 - 1214

Keywords

Adenocarcinoma, Adult, Aged, Aged, 80 and over, Apoptosis Regulatory Proteins, Beclin-1, Cell Hypoxia, Colorectal Neoplasms, Down-Regulation, Female, Humans, Hydrogen-Ion Concentration, Male, Membrane Proteins, Middle Aged, Necrosis, Prognosis, Retrospective Studies, Survival Analysis, Up-Regulation