Enzastaurin is primarily investigated for its potential in cancer treatment, particularly due to its ability to inhibit protein kinase C beta (PKCβ) and the PI3K/AKT signaling pathway. It has been studied in clinical trials for various malignancies including diffuse large B-cell lymphoma (DLBCL), glioblastoma, and other solid tumors. Its mechanism involves suppressing tumor cell proliferation and inducing apoptosis, while also inhibiting angiogenesis—reducing the formation of new blood vessels that support tumor growth. Enzastaurin has shown promise in combination therapies, especially with chemotherapy or radiation, to enhance anti-tumor effects. Despite mixed results in late-stage trials, it remains of interest for targeted therapy approaches in oncology.