Investigation of Molecular Alterations of AKT-3 in Triple-Negative Breast Cancer

Histopathology. 2014 Apr;64(5):660-70. doi: 10.1111/his.12313. Epub 2013 Dec 12.

Abstract

Aims: Triple-negative breast cancer (TNBC) is responsible for a disproportionate number of breast cancer (BC) deaths, owing to its intrinsic aggressiveness and a lack of treatment options, especially targeted therapies. Thus, there is an urgent need for the development of better targeted treatments for TNBC. Molecular alteration of AKT-3 was previously reported in oestrogen receptor (ER)-positive BC. AKT-3 has also been suggested to play a role in hormone-unresponsive BC. The aim of this study was to investigate molecular alterations of AKT-3 in TNBC, to perform associated survival analysis, and to compare these findings with the incidence of AKT-3 molecular alterations in ER-positive BC.

Results: Our study revealed AKT-3 amplification and deletions in 11% (9/82) and 13% (11/82) of TNBCs, respectively. In contrast, 1% (2/209) of ER-positive BCs were found to have AKT-3 amplifications and deletions. A higher prevalence of AKT-3 copy number gains was observed in TNBC [26% (21/82)] than in ER-positive BC [9% (19/209)]. AKT-3 amplification together with Akt-3 protein expression was negatively associated with recurrence-free survival in TNBC. Furthermore, a negative association between high AKT-3 copy number and recurrence-free survival was observed.

Conclusion: AKT-3 amplification could represent a potentially relevant oncogenic event in a subset of TNBCs that may, in turn, select cells sensitive to Akt-3 inhibitors.

Keywords: AKT-3; ER-positive breast cancer; fluorescence in-situ hybridization; molecular alterations; triple-negative breast cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers, Tumor / genetics
  • Biomarkers, Tumor / metabolism
  • Breast Neoplasms / genetics
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / mortality
  • Cohort Studies
  • Disease-Free Survival
  • Female
  • Gene Amplification
  • Gene Dosage
  • Humans
  • Immunohistochemistry
  • In Situ Hybridization, Fluorescence
  • Kaplan-Meier Estimate
  • Proto-Oncogene Proteins c-akt / genetics*
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptors, Estrogen / metabolism
  • Triple Negative Breast Neoplasms / genetics*
  • Triple Negative Breast Neoplasms / metabolism
  • Triple Negative Breast Neoplasms / mortality

Substances

  • Biomarkers, Tumor
  • Receptors, Estrogen
  • AKT3 protein, human
  • Proto-Oncogene Proteins c-akt