Fig. 1. Association of tumor Snai2 overexpression with evolution in different subtypes of breast cancer.

Survival curves (Kaplan-Meier) were obtained from the Kaplan-Meier plotter database (30). (A) Survival of patients with breast cancer in the whole cohort regardless of tumor subtype. (B) Survival of patients with the Luminal A subtype of tumors. (C) Patients with basal tumors. (D) Patients with luminal B tumors. (E) Patients with luminal B HER2+/ER+ tumors. (F) Patients with HER2+ enriched ER- tumors. The statistical significance of the Kaplan-Meier curves (A-F panels) was evaluated using the Log-Rank test, according to the public database website, Kaplan-Meier plotter. The number of patients (N) in each cohort is shown in Table S1. (G) Bioinformatics analysis of the SNAI2 mRNA levels of normal (N=5) and breast cancer samples (N=45). The data were collected from a public data set of breast cancer (GSE36295). (H, I) Bioinformatics analysis of SNAI2 mRNA levels in the stroma of normal (N=12) and breast cancer samples (N=111). The data were collected from a public data set of stromal gene expression in human breast cancer (GSE9014). (J) SNAI2 protein expression assessed in western blots of normal human fibroblast (hNFs) and CAFs obtained from human breast cancers (hCAFs). (K) Breast tumors with SNAI2 expression in the stroma and the epithelium assessed by immunohistochemistry (L) or only in the epithelium of the tumor. (M) There was no correlation between the immunohistochemical detection of SNAI2 in the epithelium and stroma of HER2+ tumors. (N) Expression of SNAI2 in the tumor stroma but not in the epithelium was associated with the proliferation of HER2+ tumors. Statistical significance in panels M and N was evaluated using Fisher's exact test. (O) Scheme showing in which HER2-positive tumor subtypes there is an association between the stromal expression of SNAI2 and tumor proliferation (measured as Ki-67 expression by immunohistochemistry), evaluated by generalized linear models. Scale bar 100 μm.