XL388 is primarily used as a potent and selective inhibitor of the eukaryotic initiation factor 4E (eIF4E) binding protein (4E-BP) pathway, specifically targeting the eIF4E/eIF4G interaction. This makes it a valuable tool in cancer research, particularly in studies involving tumor growth and proliferation driven by dysregulated protein translation. It has shown inhibitory activity against several cancer cell lines, including those of lung, breast, and prostate cancers, by suppressing cap-dependent translation, a process often hijacked by cancer cells to enhance survival and growth. In preclinical studies, XL388 demonstrates the ability to induce cell cycle arrest and promote apoptosis in tumor cells, especially in models with hyperactivated mTOR signaling. Due to its mechanism, it is often explored in combination with other targeted therapies or chemotherapeutic agents to overcome resistance and improve efficacy. Its application remains largely confined to laboratory and experimental settings, serving as a critical compound for validating the therapeutic potential of targeting translation initiation in oncology.