Medicinal plants used for treating cancer in Kenya: an ethnopharmacological overview

Abstract Background Cancer is one of the major causes of mortality worldwide. Though 30% of cancers can be treated when detected at early stages, their treatment has been compounded by resistance of tumor cells to anticancer drugs, side effects of the therapies, high treatment costs and limited access to medical services. In Africa, and particularly in the East African botanical plate, various ethnic groups cherish their traditions and embrace distinguished use of medicinal plants in the management of ailments like cancer. This study aimed at reviewing the ethnobotanical knowledge on the use of wild and cultivated plants as remedies for cancer treatment in Kenya as well as their phytochemical composition and reported anticancer activities. Main body Through extensive electronic review in PubMed, Science Direct, Scopus, Google Scholar, Web of Science, Scientific Electronic Library Online and the Google search engine, 145 plant species from 125 genera spread across 55 families were found to have been reported for cancer treatment in Kenya. The malignancies treated using the herbal remedies include squamous cell carcinoma of the gum, prostate, blood, bone, breast, colorectal, colon, oesophageal, lung, liver, skin, stomach, throat and uterine cancers. Most of the identified species have reported anticancer activities, with Toddalia asiatica , Annona muricata , Carica papaya , Catharanthus roseus, Moringa oleifera , Ocimum gratissimum , Prunus africana and Zanthoxylum paracanthum being the most studied. Conclusions Despite the widespread use of medicinal plants in the management of cancer in Kenya, the bioactivity, safety aspects, responsible anticancer molecules and clinical studies are required to elucidate the mechanism of action of the compounds and confirm the potential of the unstudied species.