Heat Shock Cognate 70 mutations in sporadic breast carcinoma

Heat Shock Cognate 70 (HSC70) is a constitutively expressed molecular chape rone, functions of which regulate the structure, subcellular localization, and turnover of cell proteins. It is also a component of the centrosome fac ilitating rearrangements during mitotic/melotic spindle formation and cytop lasmic microtubule organization. We localized HSC70 to 11q23.3, a region de leted in 40% of sporadic breast and other cancers. Sequencing demonstrated mutation in the NH2-terminal ATPase domain of HSC70 in 2 of 15 sporadic bre ast carcinomas examined. In both cases, mutation was coincident with alleli c imbalance, suggesting that HSC70 is a target of somatic mutation and dele tion in a fraction of breast carcinomas.