In view of overlapping and complementing CPC associated functions of Aurora-C and -B reported in somatic cells with studies also suggesting the two kinases co-existing in the same complex [12, 20], we performed a detailed characterization of Aurora-C interactions with Survivin and INCENP in reference to Aurora-B utilizing human cancer cell lines naturally overexpressing endogenous Aurora-C as well as with WT and mutant recombinant proteins expressed in vitro and in vivo. This evidence concerns the gene BIRC5 and cancer.