TGFB1 and juvenile polyposis syndrome: The importance of TGF-β signaling in human cancers is evident from the frequent alterations of TGF-β signaling components in hereditary human cancers and sporadic cancers [16]: for example, the autosomal dominant familial juvenile polyposis syndrome (JPS) is the most common of the hamartomatous syndromes which occurs with an incidence of about one per 100.000 births [16–18] and germline mutations in different members of the TGF-β superfamily have been described in JPS patients.