Prognostic significance of Beclin 1 in intrahepatic cholangiocellular carcinoma

Autophagy. 2011 Oct;7(10):1222-9. doi: 10.4161/auto.7.10.16610. Epub 2011 Oct 1.

Abstract

Autophagy enables cells to recycle long-lived proteins or damaged organelles. Beclin 1 plays important roles in autophagy, differentiation, apoptosis and the development and progression of cancer, but the expression of Beclin 1 and its possible role in primary intrahepatic cholangiocarcinoma (ICC) has not been reported yet. This study aimed to investigate Beclin 1 expression and its prognostic significance in ICC. First, we assessed the expression levels of Becn1 by real-time PCR in 50 ICC samples and found Becn1 mRNA expression was markedly increased in 78% (39 of 50) samples compared with normal bile duct epithelium. Beclin 1 protein expression in 108 tumor specimens from patients diagnosed with ICC was examined by immunohistochemistry and the correlation between Beclin 1 expression and clinicopathological factors were investigated. Immunopositivity for Beclin 1 was found in 72.2% (78 of 108) samples and low Beclin 1 expression was significantly associated with lymph node metastasis. The correlation between Beclin 1 expression and metastasis was validated in 46 ICC samples with lymph node metastasis. In survival analysis, low Beclin 1 expression was associated with worse overall survival (OS; p = 0.025) and disease-free survival (DFS; p = 0.027). In multivariate analysis, Beclin 1 expression, intrahepatic metastasis, lymph node metastasis and tumor size were found to be independent prognostic factors of OS. Thus, our results suggested the expression of Beclin 1 was correlated with progression and metastasis of ICC and it might serve as a novel prognostic marker for patients with ICC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Apoptosis Regulatory Proteins / metabolism*
  • Autophagy
  • Beclin-1
  • Bile Duct Neoplasms
  • Bile Ducts, Intrahepatic
  • Cholangiocarcinoma / diagnosis
  • Cholangiocarcinoma / metabolism*
  • Disease Progression
  • Female
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Liver Neoplasms / diagnosis
  • Liver Neoplasms / metabolism*
  • Lymphatic Metastasis
  • Male
  • Membrane Proteins / metabolism*
  • Middle Aged
  • Neoplasm Metastasis
  • Prognosis
  • RNA, Messenger / metabolism

Substances

  • Apoptosis Regulatory Proteins
  • BECN1 protein, human
  • Beclin-1
  • Membrane Proteins
  • RNA, Messenger