Johnstone CN, Pattison AD, Harrison PF, et al. - Given 10-20% of all human ductal adenocarcinomas are triple-negative breast cancer (TNBC), which carries a poor prognosis than other subtypes, because of the high propensity to develop distant metastases, researchers recently rigorously characterized, both at phenotypic and genomic level, four isogenic populations of MDA-MB-231 human triple-negative breast cancer cells that have a range of intrinsic spontaneous metastatic abilities in vivo, ranging from non-metastatic (MDA-MB-231_ATCC) to highly metastatic to lung, liver, spleen and spine (MDA-MB-231_HM). High upregulation of FGF13 (fibroblast growth factor homologous factor) in aggressively metastatic MDA-MB-231_HM tumours was revealed in gene expression profiling of primary tumours by RNA-Seq. Significantly worse relapse free survival was noted in both luminal A and basal-like human breast cancers in relation to higher FGF13 mRNA expression, whereas, there was no link of higher FGF13 mRNA expression with other clinical variables, and it was not upregulated in primary tumours vs normal mammary gland. Overall, FGF13 may be a treatment target for blocking metastatic outgrowth of certain TNBCs.