Egyptian Pharmaceutical Journal

REVIEW ARTICLE
Year
: 2019  |  Volume : 18  |  Issue : 1  |  Page : 1--7

Natural phenolics: a source of anticancer agents


Mohamed Amin El-Ansari, Lamyaa Fawzy Ibrahim, Mohamed Sharaf 
 Phytochemistry and Plant Systematics Department, National Research Centre, Dokki, Cairo, Egypt

Correspondence Address:
Lamyaa Fawzy Ibrahim
Phytochemistry and Plant Systematics Department, National Research Centre, Dokki-12311, Cairo
Egypt

Abstract

Cancer is a worldwide scourge, which affects people of all ages, and is rapidly becoming a global pandemic. It is one of the main leading causes of death especially in developing countries. Mankind has been trying hard to find better and cheaper treatments with fewer side effects to reduce the incidence of the disease and its consequent mortality. Natural phenolics play an important role in cancer prevention and treatment. Phenolics from medicinal plants are responsible for their chemopreventive properties and also contribute to their activity as apoptosis inducers. For many years, phenolic compounds have been intensely studied, in vitro and in vivo, for their antitumor effects. In recent years, the use of these compounds has increased considerably. In this regard, this article provides an overview of some natural phenolic compounds with approved anticancer activities.



How to cite this article:
El-Ansari MA, Ibrahim LF, Sharaf M. Natural phenolics: a source of anticancer agents.Egypt Pharmaceut J 2019;18:1-7


How to cite this URL:
El-Ansari MA, Ibrahim LF, Sharaf M. Natural phenolics: a source of anticancer agents. Egypt Pharmaceut J [serial online] 2019 [cited 2021 Dec 3 ];18:1-7
Available from: http://www.epj.eg.net/text.asp?2019/18/1/1/254968


Full Text

Phenolic compounds comprise a broad class of natural products formed mainly by plants, as well as microorganisms and marine organisms. Nowadays the interest in these compounds has increased mainly due to their diverse chemical structure and various biological activities, which is valuable in the prevention of some chronic or degenerative diseases. Phenolic compounds are widely dispersed throughout the plant kingdom representing about 9000 different phenolic structures. As secondary metabolites they also display defensive growth and development effects. They have at least one aromatic ring with one or more hydroxyl groups attached, being able to range from low molecular weight molecules to high molecular weight complex ones. Phenolic compounds generally appear as esters and glycosides rather than as free compounds due to the conferred stability of these molecules. This family of compounds is one of the most widely studied families and had been published in numerous reports due to their beneficial effects in various aspects of human health and well-being [1],[2],[3].

Since ancient times, plants have been used as remedies to treat different types of illnesses showing satisfying results. Today, more than 60% of anticancer drugs originate either from natural compounds or are derived from them, making these bioactive molecules increasingly promising for drug companies, even as prototypes of final formulations for anticancer drugs [4],[5].

The antioxidant activity of the phenolic compounds depends on their structure, in particular the number, positions of the hydroxyl groups, and the nature of substitutions on the aromatic rings. [Table 1] outlines the most important groups of plant phenolics [6].{Table 1}

 Plant phenolics with anticancer activity



Cancer is a growing public crisis. The estimated worldwide new incidences are about six million cases per year. It is the second major cause of death after cardiovascular diseases. A large number of plants have been tested for their anticancer activities, and plenty of compounds have survived to be potential leads.

The therapeutic effect of some isolated natural phenolics on malignant tumors are tabulated in [Table 2]. The name of the natural phenolic compound, the natural source (representative species and family) and the references are provided. Structures of some selected phenolic compounds are shown in [Figure 1].{Table 2}{Figure 1}

 Conclusion



Plants have been a prime source of highly effective conventional drugs for the treatment of many types of cancer. In many instances, the actual compounds isolated from the plants may not serve as a drug, but lead to the development of potential novel agents. With the development of new technologies, some of the natural tested compounds which have failed in earlier clinical studies are now stimulating renewed interest. The ability to attach agents to carrier molecules directed to specific tumors holds promising results for the effective targeting of highly cytotoxic natural products against tumors, while avoiding their toxic side effects on normal healthy tissues. With the urgent need for the detection of new proteins having significant regulatory effects on tumor cell cycle progression, and their conversion into valuable natural targets, molecules isolated from plants and other natural organisms are proving to be an important source of novel inhibitors of the action of these key proteins and have the potential for development into selective anticancer agents.[94]

Acknowledgements

The authors thank the National Research Centre (NRC) for the facilities provided.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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