There was a higher frequency of grade 3 (83.3% vs 45.4%, p = 0.005), oestrogen receptor (ER) negative (66.7% vs 26.3%, p < 0.001) and human epidermal growth factor receptor 2 (HER2)-positive (66.7% vs 23.4%, p < 0.001) tumours among NF1 patients compared to non-NF1 breast cancers.
By evaluating HER2 expression and <i>NF1</i> alterations in unselected invasive breast cancers in TCGA datasets, we discovered that among samples with <i>ERBB2</i> CN gain/amplification, the HER2 mRNA and protein expression were much more pronounced in <i>NF1</i>-mutated/deleted samples in comparison with <i>NF1</i>-unaltered samples.
The combined somatic-cell hybrid and pulsed-field gel analysis we report here favors the probe order D17Z1-HHH202-TH17.19-CRYB1-17L1-NF1- (EW206, EW207, EW203, L581, L946)-(ERBB2, ERBA1).