Priming immunity via herbal components and their nanomedicines for the treatment of cancer

Recently, immunotherapy has redefined cancer treatment by promoting the rapid killing of tumor cells through the immune system. Herbal medicines have been increasingly used as adjunct therapies to complement cancer treatment along with chemotherapy and radiotherapy to delay tumor development, reduce pain, and prolong patient survival. However, the potential immunotherapeutic effects of these herbal derivatives are limited by their structural instability, poor membrane permeability, and low bioavailability. To address this issue, nanotechnology has been used to enhance the activity of active compounds. Therefore, this review focuses on the effectiveness of the active ingredients of herbal medicines in suppressing tumor progression by modulating both the innate and adaptive immune systems, challenges in their delivery, and the application of nanocarriers for the effective delivery of these herbal components.