Transcription Factor Ap-2beta In Development, Differentiation And Tumorigenesis

To date, the AP-2 family of transcription factors comprises five members. Transcription factor AP-2beta (TFAP2B)/AP-2 beta was first described in 1995. Several studies indicate a critical role of AP-2 beta in the development of tissues and organs of ectodermal, neuroectodermal and also mesodermal origin. Germline mutation of TFAP2B is known to cause the Char syndrome, an autosomal dominant disorder characterized by facial dysmorphism, patent ductus arteriosus and anatomical abnormalities of the fifth digit. Furthermore, single-nucleotide polymorphisms in TFAP2B were linked to obesity and specific personality traits. In neoplasias, AP-2 beta was first described in alveolar rhabdomyosarcoma. Immunohistochemical staining of AP-2 beta is a recommended ancillary test for the histopathological diagnosis of this uncommon childhood malignancy. In neuroblastoma, AP-2 beta supports noradrenergic differentiation. Recently, the function of AP-2 beta in breast cancer (BC) has gained interest. AP-2 beta is associated with the lobular BC subtype. Moreover, AP-2 beta controls BC cell proliferation and has a prognostic impact in patients with BC. This review provides a comprehensive overview of the current knowledge about AP-2 beta and its function in organ development, differentiation and tumorigenesis.