Defective Beclin-1 and elevated hypoxia-inducible factor (HIF)-1α expression are closely linked to tumorigenesis, differentiation, and progression of hepatocellular carcinoma

Tumour Biol. 2015 Jun;36(6):4293-9. doi: 10.1007/s13277-015-3068-0. Epub 2015 Jan 17.

Abstract

Hepatocellular carcinoma (HCC) is an aggressive cancer with a poor prognosis. Autophagy and hypoxia have been involved in HCC tumorigenesis. In the present study, we examined the relationship between Beclin-1 expression and hypoxia-inducible factor (HIF)-1α expression in HCC by immunohistochemistry on 65 tumor specimens. Their correlations with clinicopathological features were also explored. There was a loss of Beclin-1 protein expression in 49.2 % of HCC. Beclin-1 expression was only significantly correlated with virus infection status (p = 0.025) and marginally associated with HCC grade (p = 0.057). Forty-two tumors (64.6 %) showed high HIF-1α expression, and it was significantly associated with large tumor size (p = 0.003), multifocal tumors (p = 0.038), and advanced stage (p = 0.043). Beclin-1 expression was significantly associated with HIF-1α expression (p = 0.001). HCC cases were further stratified according to their hypoxia status into hypoxic and normoxic groups. In the hypoxic group, Beclin-1 expression was negatively correlated with HCC high tumor grade (p < 0.001), advanced stage (p = 0.013), large size (p = 0.002), and multifocal tumors (p = 0.047). In the normoxic group, no significant relations between Beclin-1 expression and any of the clinicopathological parameters were identified. Our findings that reduced Beclin-1 and high HIF-1α expression are associated with the development and progression of HCC may provide molecular therapeutic targets toward inhibiting HCC development and progression.

MeSH terms

  • Adult
  • Aged
  • Apoptosis Regulatory Proteins / biosynthesis*
  • Apoptosis Regulatory Proteins / genetics
  • Beclin-1
  • Carcinogenesis / genetics
  • Carcinoma, Hepatocellular / genetics*
  • Carcinoma, Hepatocellular / pathology
  • Cell Differentiation / genetics
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / biosynthesis*
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics
  • Liver Neoplasms / genetics*
  • Liver Neoplasms / pathology
  • Male
  • Membrane Proteins / biosynthesis*
  • Membrane Proteins / genetics
  • Middle Aged

Substances

  • Apoptosis Regulatory Proteins
  • BECN1 protein, human
  • Beclin-1
  • HIF1A protein, human
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Membrane Proteins