Medicinal plant-derived therapeutics for treatment of neoplasms in modern and traditional systems of medicine

Abstract

Cancer poses an important challenge for mankind. Plants have provided major remedies and clues for its treatment. Plant-derived compounds (phytomolecules) are an important source of several clinically-useful anticancer drugs. Here we summarize the current status of plant-based therapies for cancer treatment. Examples of clinically-useful anticancer phytomolecules are taxol, vincristine, vinblastine, camptothecin derivatives -topotecan and irinotecan, and etoposide derived from epipodophyllotoxin. Several promising compounds like, combretastatin A-4 phosphate and flavopiridol are in various stages of clinical development. IPI-926, a semi-synthetic analog of steroid alkaloid cyclopamine, has shown promise against several cancers including pancreatic cancer and leukemia and has been under clinical trials. Besides, there are several other promising molecules that are receiving attention. Most of the drugs are directly used after isolation and purification from renewable resources or they can be produced after efficient chemical modification of the same. Simultaneously, it must be appreciated that traditional systems of medicine like Ayurveda have also described cancerlike diseases (with alternative names like Arbuda, Granthi and Gulma) and prescribed plant-based therapies for curing them. Logically, if modern science takes cues from Ayurveda and targets such plants, a higher probability of hit rates in anticancer drug discovery is expected.