A gene expression signature that predicts the therapeutic response of the basal-like breast cancer to neoadjuvant chemotherapy

Breast Cancer Res Treat. 2010 Oct;123(3):691-9. doi: 10.1007/s10549-009-0664-y. Epub 2009 Dec 6.

Abstract

Several gene expression profiles have been reported to predict breast cancer response to neoadjuvant chemotherapy. These studies often consider breast cancer as a homogeneous entity, although higher rates of pathologic complete response (pCR) are known to occur within the basal-like subclass. We postulated that profiles with higher predictive accuracy could be derived from a subset analysis of basal-like tumors in isolation. Using a previously described "intrinsic" signature to differentiate breast tumor subclasses, we identified 50 basal-like tumors from two independent clinical trials associated with gene expression profile data. 24 tumor data sets were derived from a 119-patient neoadjuvant trial at our institution and an additional 26 tumor data sets were identified from a published data set (Hess et al. J Clin Oncol 24:4236-4244, 2006). The combined 50 basal-like tumors were partitioned to form a 37 sample training set with 13 sequestered for validation. Clinical surveillance occurred for a mean of 26 months. We identified a 23-gene profile which predicted pCR in basal-like breast cancers with 92% predictive accuracy in the sequestered validation data set. Furthermore, distinct cluster of patients with high rates of cancer recurrence was observed based on cluster analysis with the 23-gene signature. Disease-free survival analysis of these three clusters revealed significantly reduced survival in the patients of this high recurrence cluster. We identified a 23-gene signature which predicts response of basal-like breast cancer to neoadjuvant chemotherapy as well as disease-free survival. This signature is independent of tissue collection method and chemotherapeutic regimen.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use*
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / mortality
  • Breast Neoplasms / pathology
  • Chemotherapy, Adjuvant
  • Clinical Trials as Topic
  • Cluster Analysis
  • Disease-Free Survival
  • Female
  • Gene Expression Profiling* / methods
  • Gene Expression Regulation, Neoplastic*
  • Genetic Testing*
  • Humans
  • Kaplan-Meier Estimate
  • Middle Aged
  • Neoadjuvant Therapy
  • Neoplasms, Basal Cell / drug therapy*
  • Neoplasms, Basal Cell / genetics*
  • Neoplasms, Basal Cell / mortality
  • Neoplasms, Basal Cell / pathology
  • Oligonucleotide Array Sequence Analysis
  • Predictive Value of Tests
  • Reproducibility of Results
  • Time Factors
  • Treatment Outcome