Figure 1.

YTHDC1 promotes TNBC metastasis. A) Breast cancer patient survival in patients expressing high or low levels of YTHDC1 from TCGA data. Log-rank test. B) Box-whisker plot of YTHDC1 protein levels in tumor and normal patient samples from CPTAC data. Z-values represent standard deviations from the median across samples. t-test. C) Western Blot of YTHDC1 levels across different TNBC cells and non-tumorigenic MCF10A cells. D-F) Cells were engrafted into the 4^th mammary fat pad of 6-9 week-old NSG mice. 1×10⁶ MDA-MB-231 cells overexpressing YTHDC1 (OE) or vector were engrafted into each mouse. n = 10/group. D) Quantification of lung metastases by chemiluminescence (top) and associated images (bottom). t-test. E) Number and size of lung metastases (left) and corresponding images of lung samples (right) stained for human CK18. Each point represents the average number or size of 10 metastatic nodules in each mouse. Scale bar: 100 μm. n = 5/group. t-test. F) Volume of primary tumor measured twice weekly. Two-way ANOVA. G-H) 2×10⁵ SUM159 cells overexpressing YTHDC1 (OE) or vector were engrafted into each mouse. n = 5/group. G) Quantification of lung metastases by chemiluminescence and associated images. t-test. H) Volume of primary tumor measured twice weekly. Two-way ANOVA. I-J) 1×10⁶ MDA-MB-231 cas9 cells transduced with either control sgRNA (sgNS) or sgRNAs targeting YTHDC1 (sgA and sgB) were engrafted into each mouse. n = 5/group. I) Number and size of lung metastases and images of lung samples stained for human CK18. Each point represents the average number or size of 10 metastatic nodules in each mouse. n = 5/group. Scale bar: 100 μm. One-way ANOVA compared to sgNS. J) Volume of primary tumor measured twice weekly. Two-way ANOVA. The data are presented as the mean ± SD for tumor volume plots; NS = not significant, *P < 0.05.