FHIT alterations in breast cancer

The FHIT gene encodes a diadenosine hydrolase and may be involved in growth control Pathways of the cell. Studies on protein-protein interactions, cel l lines, including tumourigenicity tests, and knockout mice suggest that th e Fhit protein is involved in cell proliferation and apoptosis, and might a ct as a tumour suppressor In several different cancers, including breast ca ncer, alterations in the FHIT gene have been detected in high frequency. Th e most common alterations are: deletions, DNA hypermethylation, abnormal tr anscripts and reduced expression at RNA and protein le-vel. The FHIT gene i s located at the FRA3B fragile site at chromosome 3p14.2, and alterations i n the FHIT gene and Fhit protein have been found associated with genome ins tability, particularly in BRCA2 mutated breast tumours. This paper will foc us on some of the functional aspects of the Fhit protein with respect to tu mour pathogenesis and on aberrations detected in breast cancer.