MLN2238 is primarily used in the field of oncology as a proteasome inhibitor. It plays a crucial role in targeting and disrupting the function of proteasomes, which are responsible for breaking down proteins within cells. By inhibiting proteasome activity, MLN2238 induces the accumulation of damaged or misfolded proteins, leading to cell stress and ultimately apoptosis in cancer cells. This mechanism makes it particularly effective in the treatment of certain types of cancers, such as multiple myeloma and mantle cell lymphoma. Its application is often explored in clinical trials to evaluate its efficacy and safety in combination with other therapies, aiming to improve patient outcomes and provide new treatment options for resistant or relapsed cancers.