LY2857785 is a potent and selective inhibitor of dihydroorotate dehydrogenase (DHODH), an enzyme involved in the de novo pyrimidine biosynthesis pathway. Its primary application lies in oncology research, particularly in the study of cancer cell proliferation. Since rapidly dividing cancer cells rely heavily on pyrimidine synthesis for DNA and RNA production, inhibiting DHODH with LY2857785 disrupts nucleotide supply, leading to cell cycle arrest and apoptosis. This compound has shown antiproliferative effects in various tumor models, especially in hematological malignancies such as acute myeloid leukemia (AML). It is used as a research tool to explore the therapeutic potential of metabolic targeting in cancer. Additionally, LY2857785 has been investigated for its ability to cross the blood-brain barrier, making it relevant for studying central nervous system tumors. Beyond oncology, inhibitors of DHODH like LY2857785 are also explored in antiviral research, as some viruses depend on host pyrimidine pools for replication. However, its main focus remains in preclinical cancer studies to validate DHODH as a viable drug target and to understand resistance mechanisms in tumor metabolism.