Flow cytometry data showed that CXCL1 treatment did not increase CD44+/CD24- or aldehyde dehydrogenase assays (ALDH+) in the MDA-MB-231 and MCF-7 breast cancer cell lines (Supplementary Figure 2), indicating that CSC-enhancing effects may not explain CXCL1-induced metastasis. The gene discussed is CXCL1; the disease is breast cancer.