Abstract.
The helicase-like transcription factor (HLTF) belongs to the SWI/SNF family of chromatin-remodeling factors. Several SWI/SNF genes are disrupted in cancer, suggesting their possible role as tumor suppressors. Similarly, the HLTF gene was found to be inactivated by hypermethylation in a significant number of colon, gastric and uterine tumors, indicating that HLTF silencing may confer a growth advantage and that HLTF could be considered as a tumor suppressor gene. However, 20-fold HLTF overexpression was detected in various transformed cell lines, suggesting that HLTF could be associated with neoplastic transformation and act more like an oncogene. Moreover, HLTF activation was recently linked to the initial steps of carcinogenesis in an experimental model of estrogen-induced kidney tumors. Those apparently contradictory observations suggest that HLTF might play various roles in cancer. In this review, we will try to reconcile all these data in order to specify the role of HLTF in cancer progression.
Keywords. Cancer, HLTF, oncogene, PAI-1, promoter methylation, SMARCA3, SWI/SNF, tumor suppressor
Footnotes
Received 24 August 2007; received after revision 17 October 2007; accepted 23 October 2007