Extended Data Figure 5 : Cell density and regulation of PGR and HER2 signalling in human cell lines.

From: Early dissemination seeds metastasis in breast cancer

Extended Data Figure 5

To investigate whether human breast cancer cells display similar regulatory circuits as found in mouse cells, we selected 16 cell lines of different breast cancer subtypes. a, HER2 mRNA expression levels in 15 human cell lines compared to the hTERT-HME cell line. Different colours indicate the subtype of breast cancer of each cell line. b, The expression of miR-9-5p in human breast cancer cell lines compared to hTERT-HME cells. Note that cell lines highly expressing HER2 (see a) express more miR-9-5p similar to primary tumours of BALB-NeuT and TUBO cells (see Fig. 3b, c), whereas two HER2high/PGRhigh cell lines, BT474 and T47D, do not express miR-9-5p similar to human HER2high/PGRhigh samples (see Fig. 5d). c, High cell density leads to upregulation of HER2 mRNA (top) or protein levels (bottom) in several cell lines. Only four cell lines were analysed for protein level (HER2 level was not influenced by cell density in CAMA1; HER2 level regulated by cell density in HCC1806, MDA-MB-231 and MCF7). Numbers below the blots denote fold change of HER2 in high density compared to low density normalized over β-actin. d, Expression of miR-9-5p is upregulated by cell density in SKBR3, HCC1937, HCC1806 and MCF7 cell lines. e, Migration and sphere-forming potential of 10 out of 16 cell lines grown at low and high densities, and treated with PIPS or progesterone. The first 7 cell lines regulate HER2 transcripts by density (see c) and their response to PIPS is similar to TUBO cells and primary mammary cell cultures of BALB-NeuT mice (see Fig. 2 and Extended Data Fig. 4l, m). The remaining three cell lines do not regulate HER2 transcripts by cell density, but respond to progesterone similarly to the TUBO cell line and primary mammary cell cultures of BALB-NeuT mice (see Fig. 2 and Extended Data Fig. 4l, m). We did not perform functional assays with BT549 (triple negative subtype), T47D (luminal, MCF7-like), MDA-MB-175, ZR75-1 (luminal, CAMA1-like), hTERT-HME (transformed normal, similar to MCF10A) because of breast cancer subtype redundancy or poor growth (HCC1569). y axes show the percentage of migrating cells (left) and observed spheres (right) relative to seeded cells. Data are mean ± s.d. For gel source data, see Supplementary Fig. 1.