Deletion of Forkhead Box M1 transcription factor reduces malignancy in laryngeal squamous carcinoma cells.

The transcription factor, Forkhead Box M1 (FoxM1), has a specific expression pattern during the cell cycle. It also plays an important role in cellular developmental pathways and in the maintenance of homeostasis between cell proliferation and apoptosis. However, the precise role and molecular mechanisms associated with FoxM1 in laryngeal squamous carcinoma remain unclear. Therefore, laryngeal squamous carcinoma cells were transfected with FoxM1-targeted small interfering RNA (siRNA) and compared with cells transfected with a control siRNA. Assays of these two treatment groups detected a decrease in cell viability associated with down-regulation of FoxM1 expression, and resulted in an inhibition of cell proliferation, migration, and invasion. These phenotypes were also associated changes in expression of VEGF and MMP-2, a decrease in expression of cyclin B, and an increase in expression of p27. These findings suggest that deregulation of FoxM1 protein signaling is sufficient to affect tumorigenesis and cancer progression. These results also indicate that inhibition of FoxM1 represents an attractive target for cancer therapy.