Fig. 6.

HER2 expression primes cells for hypoxia across breast cancer cell lines. a Genes which were primed for either acute or chronic hypoxia by HER2 overexpression in MCF7 were compared to HER2 expression in a data set containing gene expression data from 173 samples representing 77 different breast cancer cell lines. Genes with significant (P < 0.005) correlation to HER2 expression in this data set are shown (acute n = 25, chronic n = 33 with 16 genes represented in both acute and chronic hypoxia). The expression of these genes is shown in a heatmap with cell lines ordered by HER2 expression. b Five example genes with roles in cancer pathology which are primed by HER2 for both acute and chronic hypoxia and correlate to HER2 in breast cancer cell lines. Bar charts (error bars = SEM, n = 3) of the expression of these genes in MCF7 and MCF7-HER2 is shown to demonstrate their increased hypoxic upregulation in HER2-overexpressing cells. P values and Pearson’s correlation to HER2 expression in the cell lines data set are shown