From gene expression analyses performed on a cohort of normal breast tissues and human BC biopsies obtained from Institut Curie, where all BC subtypes are almost equally represented, we found that RNA transcript levels of the human protein kinase monopolar spindle 1 (hMps1/TTK) gene, which encodes a dual serine/threonine kinase involved in the mitotic spindle assembly checkpoint (SAC) [17], [18], are highly increased in TNBC samples compared to the other BC subgroups and normal tissue samples. Here, TTK is linked to breast cancer.