Methods are provided for identifying agents capable of modulating cap-dependent RNA translation by comparing translation efficiency in the presence and absence of the agent in an in-vitro or in-vivo translation system that comprises eIF4A and an mRNA having one or more eIF4A-dependent translation-controlling motifs. The modulation of translation in the presence of the agent indicates the agent as capable of modulating cap-dependent mRNA translation. The method can be used to identify anti-cancer agents and oncogenes that may be responsible for tumorigenesis.