Fig. 2

Expression of biological markers in MCF-7, BC5, BrCCh1, and BN1 cells. a Expression levels of the progesterone receptor (PGR), oestrogen receptor (ER) α and β, and Cyp19 mRNA in primary cell lines according to real-time polymerase chain reaction (PCR) analysis. The expression of specific mRNAs was normalised to the expression level of glyceraldehyde 6-phosphate dehydrogenase (GAPDH) mRNA. The expression levels of PGR, ERα, ERβ, and Cyp19 mRNA in the different cell lines are shown relative to their expression level in MCF-7 cells where it was set equal to 1. Statistical analysis included the results of two independent experiments (mean ± SD). * The difference between the experimental group and the control (MCF-7) group was statistically significant at p < 0.05. b Representative flow cytometry data of human epidermal growth factor receptor HER2(CD340)/HER3 positive cells in BC5 and BrCCh1 cells. Stained cells were gated according to isotype control samples so that these cells were negative to both HER2/HER3 (left bottom quadrant). Cells from right upper quadrant were accounted as HER2/HER3 double-positive cells