A method of killing a cell having a mutation in an Adenomatous polyposis coli (APC) gene is disclosed. The method comprises contacting the cell with an inhibitor of Casein kinase I (CKI), the CKI being selected from the group consisting of CKI-alpha and CKI-delta and CKI-epsilon, thereby killing the cell. The method may be used for treating cancers. Pharmaceutical compositions for treatment of cancers are also disclosed.
