P16 and p53 play distinct roles in different subtypes of breast cancer

PLoS One. 2013 Oct 11;8(10):e76408. doi: 10.1371/journal.pone.0076408. eCollection 2013.

Abstract

Breast cancers are heterogeneous and complex diseases, and subtypes of breast cancers may involve unique molecular mechanisms. The p16(INK4a) and p53 pathways are two of the major pathways involved in control of the cell cycle. They also play key roles in tumorigenesis. However, whether the roles of these pathways differ in the subtypes of breast cancer is unclear. Therefore, p16 and p53 expression were investigated in different breast cancer subtypes to ascertain their contributions to these cancers. A total of 400 cases of non-invasive ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC), including the major molecular subtypes luminal-A, luminal-B, Her-2, and triple-negative subtypes, and 50 cases of normal controls were compared. Luminal-A cancers expressed the lowest level of p16 among the subtypes in DCIS, and the level of p16 expression was up-regulated in the luminal-A of IDC (P<0.008). Triple-negative breast cancers were characterized by a correlation of p53 overexpression with a high level of p16 expression. Luminal lesion types with high p16 expression in DCIS were found to be more likely to develop into aggressive breast cancers, possibly promoted by p53 dysfunction. Taken together, the present study suggest that p16 expression in luminal-A breast cancers is associated with their progression from DCIS to IDC, and both p53 and p16 expressions are important for the development of triple-negative breast cancers in DCIS and IDC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Breast Neoplasms / classification*
  • Breast Neoplasms / genetics
  • Breast Neoplasms / metabolism*
  • Breast Neoplasms / pathology
  • Carcinoma, Intraductal, Noninfiltrating / genetics
  • Carcinoma, Intraductal, Noninfiltrating / pathology
  • Cyclin-Dependent Kinase Inhibitor p16 / genetics
  • Cyclin-Dependent Kinase Inhibitor p16 / metabolism*
  • Down-Regulation / genetics
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Middle Aged
  • Mutation / genetics
  • Risk Factors
  • Signal Transduction / genetics
  • Triple Negative Breast Neoplasms / genetics
  • Triple Negative Breast Neoplasms / pathology
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*
  • Up-Regulation / genetics

Substances

  • Cyclin-Dependent Kinase Inhibitor p16
  • Tumor Suppressor Protein p53

Grants and funding

This study was supported by the funding of The Affiliated Tumour Hospital of Harbin Medical University (JJZ2010-04), the “Wu Liande” funding of Harbin Medical University (WLD-QN1118), The National Natural Science Fund (81172498) and the Technological innovation talent research special funds of Harbin (2011RFXYS056). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.