Cap-dependent translation and control of the cell cycle.

The control of gene expression at the translational level has emerged in the past decade as an important aspect of cell growth, proliferation and malignant transformation. Translation is primarily regulated at the initiation step, and mitogen-dependent signaling pathways converge to modulate the activity of translation initiation factors. In most tumors tested, at least one translation initiation factor is overexpressed and overexpression of translation initiation factors often provokes transformation. Malignant transformation could be caused by the increased translation of a subset of mRNAs encoding important proteins which are required for cell growth and proliferation. These mRNAs usually possess regulatory sequences that render their translation more sensitive to changes in the activity of translation initiation factors. In this chapter, we describe recent advances illustrating the importance of translation in cell cycle progression and cell transformation. Control of translation initiation may represent an excellent target for antitumor drugs.