engleski

Mutations of Hh-Gli Signaling Pathway Genes in Basal Cell Carcinomas (BCCs)

Basal cell carcinoma (BCC) of the skin is the most common human cancer, and shows a continuously increasing incidence. BCCs occur predominantly on sun-exposed skin of elderly fair-skinned people. Several tumor suppressor genes and oncogenes have been implicated in the pathogenesis of BCCs, most of them beeing members of the Hedgehog-Gli (Hh-Gli) signaling pathway. Hh-Gli signaling pathway is one of the fundamental signaling pathways in embryonic development and is required in vertebrates for normal development of many structures, including the neural tube, axial skeleton, skin and hair. Normally, a secreted protein Hedgehog (Hh) binds to a transmembrane protein Patched (Ptch), which causes release of another transmembrane protein Smoothened (Smo) from its repression by Ptch. This triggers a signaling cascade in the cytoplasm which leads to translocation of the activated transcription factor Gli to the nucleus and expression of target genes (Gli, Ptch, WNT and TGF beta family members, various cyclins), involved in cell proliferation, while Ptch acts as a limiting factor by blocking pathway activity. Aberrant activation of the pathway in adult tissue is associated with the development of various tumors (BCC, medulloblastoma, pancreatic, gastrointestinal etc ). In our research we investigated mutation status of several Hh-Gli pathway genes in sporadic BCCs. The mutation screening was performed by high resolution melting approach, which is based on differences in melting curves caused by variations in nucleotide sequence ; detected variants were confirmed by direct sequencing. Our results show mutations in several pathway members (SHH, PTCH, SUFU) implicating their involvement in tumor pathogenesis.

basal cell carcinoma ; PTCH ; Hh-Gli Signaling Pathway

nije evidentirano