Therapeutic Emergence of Rhein as a Potential Anticancer Drug: A Review of Its Molecular Targets and Anticancer Properties

Abstract

According to the World Health Organization (WHO), cancer is the second-highest cause of mortality in the world, and it kills nearly 9.6 million people annually. Besides the fatality of the disease, poor prognosis, cost of conventional therapies, and associated side-effects add more burden to patients, post-diagnosis. Therefore, the search for alternatives for the treatment of cancer that are safe, multi-targeted, effective, and cost-effective has compelled us to go back to ancient systems of medicine. Natural herbs and plant formulations are laden with a variety of phytochemicals. One such compound is rhein, which is an anthraquinone derived from the roots of Rheum spp. and Polygonum multiflorum. In ethnomedicine, these plants are used for the treatment of inflammation, osteoarthritis, diabetes, and bacterial and helminthic infections. Increasing evidence suggests that this compound can suppress breast cancer, cervical cancer, colon cancer, lung cancer, ovarian cancer, etc. in both in vitro and in vivo settings. Recent studies have reported that this compound modulates different signaling cascades in cancer cells and can prevent angiogenesis and progression of different types of cancers. The present review highlights the cancer-preventing and therapeutic properties of rhein based on the available literature, which will help to extend further research to establish the chemoprotective and therapeutic roles of rhein compared to other conventional drugs. Future pharmacokinetic and toxicological studies could support this compound as an effective anticancer agent.

Broad-Spectrum Preclinical Antitumor Activity of Chrysin: Current Trends and Future Perspectives

“…Taking everything into account, studies agree with the fact that natural products are versatile compounds in cancer therapy, and due to their capacity in targeting various molecular pathways in cancer therapy [ 41 , 42 , 43 , 44 , 45 ], they can be considered as potential agents in the field of cancer therapy. In the next sections, we focus on chrysin as an efficient anti-tumor agent in different cancers.…”

COVID-19, cytokines, inflammation, and spices: How are they related?

“…Various phytochemical and natural compounds obtained from different parts of plants have been a part of traditional medicine for ages and consumed for their health benefits as well as efficacy against a plethora of diseases [ [201] , [202] , [203] , [204] , [205] , [206] , [207] , [208] , [209] , [210] , [211] , [212] , [213] , [214] , [215] ].…”

Compounds from Natural Sources as Protein Kinase Inhibitors

“…Furthermore, several pathways or proteins regulating cell survival are possible targets of rhein. Those proteins are serine/threonine kinases, like Akt kinase, CDK, and MAPK (MEK, ERK) [ 179 ].…”