LY2874455 is a potent small-molecule inhibitor that targets fibroblast growth factor receptors (FGFRs), including FGFR1, FGFR2, FGFR3, and FGFR4. It is primarily used in cancer research due to its ability to block FGFR signaling pathways that are often dysregulated in various tumors. This compound shows promise in treating cancers with FGFR gene amplifications, mutations, or fusions, such as bladder cancer, gastric cancer, and hepatocellular carcinoma. Due to its multi-kinase inhibition profile, LY2874455 is also used to study resistance mechanisms to other targeted therapies, especially in tumors that develop bypass signaling through FGFR pathways. It has demonstrated antiproliferative effects and induction of apoptosis in FGFR-dependent cell lines, making it a valuable tool in preclinical oncology studies. In addition, LY2874455 is employed in pharmacokinetic and pharmacodynamic studies to evaluate the efficacy of FGFR inhibition in animal models. Its ability to overcome common resistance mutations in FGFRs enhances its utility in developing next-generation targeted therapies.