Figure 1

BORG expression correlates with the malignant and metastatic potential of breast cancers. (a) BORG expression across common breast cancer cell lines as determined by publicly available RNA-seq datasets. (b and c) BORG expression in 42 primary TNBC (b) or 42 ER-positive (c) breast tumors as compared to corresponding normal tissue using publicly available RNA-seq datasets (*P < 0.01; Mann-Whitney U Test). (d) BORG expression in 25 ductal carcinoma in situ (DCIS) lesions and 10 normal breast tissue organoids (i.e. DCIS; *P < 0.01; Mann-Whitney U Test). (e) BORG expression in normal colonic, primary colorectal, and colorectal metastasis tissue derived from 18 patients and analyzed using publicly available RNA-seq datasets (n.s.≈ P = 0.4622; Mann-Whitney U Test). (f) BORG expression was quantified via qRT-PCR in the 4T1 progression series propagated in compliant [C] or rigid [R; 3 mg/ml type I collagen] 3D-cultures. (g) TGF-β1 (5 ng/ml) stimulated BORG expression in NME cells undergoing EMT. (h) BORG expression was significantly higher in metastatic D2.A1 cells versus their latent D2.OR counterparts propagated in 3D-culture (*P < 0.05). (i) Rigid 3D-cultures significantly induced BORG expression in D2.OR organoids (*P < 0.05).