HAS2 and breast cancer: In the current study involving 544 cells derived from human mammary fibroblasts cocultured with human breast cancer cells in a nude mouse model [4], although LEF1 was expressed, knockdown of LEF1 did not significantly alter HAS2 expression (log2FC [544‐shLEF1/544‐shCtrl] = −0.53; padj = 0.39 in DESeq2 analysis).