Since some of the mutated genes responsible for the inherited endocrine tumor phenotypes and the subsequent haploinsufficiency of their encoded proteins, such as parafibromin, APC, PRKAR1A, PTEN, NF1, tuberin and hamartin, were shown to be directly involved in the development of the syndrome-specific skeletal abnormalities, targeting their downstream dysregulated signaling pathways represent potential targets for treatments not only of the tumor manifestations but also of the bone affections. The gene discussed is APC; the disease is neoplasm.