BRCA1, BRCA2 and PALB2 mRNA expression as prognostic markers in patients with early breast cancer

Abstract

Breast cancer (BC) poses a challenge in establishing new treatment strategies and identifying new prognostic and predictive markers due to the extensive genetic heterogeneity of BC. Very few studies have investigated the impact of mRNA expression of these genes on the survival of BC patients. Methods: We examined the impact of the mRNA expression of breast cancer gene type 1 (BRCA1), breast cancer gene type 2 (BRCA2), and partner and localizer of BRCA2 (PALB2) on the metastasis-free survival (MFS) of patients with early BC using microarray gene expression analysis. Results: The study was performed in a cohort of 461 patients with a median age of 62 years at initial diagnosis. The median follow-up time was 147 months. We could show that the lower expression of BRCA1 and BRCA2 is significantly associated with longer MFS (p < 0.050). On the contrary, the lower expression of PALB2 was correlated with a shorter MFS (p = 0.049). Subgroup survival analysis identified the prognostic influence of mRNA expression for BRCA1 among patients with luminal- B-like BC and for BRCA2 and PALB2 in the subset of patients with luminal-A-like BC (p < 0.050). Conclusions: According to our observations, BRCA1, BRCA2, and PALB2 expression might become valuable biomarkers of disease progression.