Question

Choose a phytochemical and discuss its role in cancer prevention. Discuss how to incorporate this into one's diet and how to increase its potency. Please cite references.

Answer 1

Phytochemicals is generally used to describe plant compounds that are under research with unestablished effects on health and are not scientifically defined as essential nutrients. Regulatory agencies governing food labeling in Europe and the United States have provided guidance for industry limiting or preventing health claims about phytochemicals on food product or nutrition labels.

Despite advances in modern medicine, cancer is still the

major cause of mortality in both developing and developed

countries. Search for safer and more eective chemopreven-

tion and treatment strategy is a need for the improvement

of patient care in the field. Prevention may be more eective

and less costly because cancer is largely a preventable disease which could be attributed to a greater extent to lifestyle. Dietary phytochemicals hsve been used for the treatment of cancer throughout hisdue to their safety, low toxicity, and general availability. Population based studies suggest that a reduced risk of cancer is associated with high consumption

of vegetables and fruits. Promising phytochemicals not only

disrupt aberrant signaling pathways leading to cancer but

also synergize with chemotherapy and radiotherapy. us,

the cancer chemoprevention and therapeutic potential of

naturally occurring phytochemicals are of great interest. In

this special issue we have collected many interesting original

research articles and reviews that provide solid evidence to

support the application of phytochemicals or dietary agents

in prevention and treatment of cancer.

Plants are composed entirely of chemicals of various kinds.Phytochemicals are chemicals produced by plants through primary or secondary metabolism.They generally have biological activity in the plant host and play a role in plant growth or defense against competitors, pathogens, or predators.

Phytochemicals generally are regarded as research compounds rather than essential nutrients because proof of their possible health effects has not been established yet Phytochemicals under research can be classified into major categories, such as carotenoids and polyphenols, which include phenolic acids, flavonoids, and stilbenes/lignans.^[5] Flavonoids can be further divided into groups based on their similar chemical structure, such as anthocyanins, flavones, flavanones, and isoflavones, and flavanols. Flavanols further are classified as catechins, epicatechins, and proanthocyanidins.

A converse exists in the case of carotenoids, such as lycopene present in tomatoes, which may remain stable or increase in content from cooking due to liberation from cellular membranes in the cooked food. Food processing techniques like mechanical processing can also free carotenoids and other phytochemicals from the food matrix, increasing dietary intake.

Despite advances in modern medicine, cancer is still the major cause of mortality in both developing and developed countries. Search for safer and more effective chemoprevention and treatment strategy is a need for the improvement of patient care in the field. Prevention may be more effective and less costly because cancer is largely a preventable disease which could be attributed to a greater extent to lifestyle. Dietary phytochemicals have been used for the treatment of cancer throughout history due to their safety, low toxicity, and general availability. Population based studies suggest that a reduced risk of cancer is associated with high consumption of vegetables and fruits. Promising phytochemicals not only disrupt aberrant signaling pathways leading to cancer but also synergize with chemotherapy and radiotherapy. Thus, the cancer chemoprevention and therapeutic potential of naturally occurring phytochemicals are of great interest. In this special issue we have collected many interesting original research articles and reviews that provide solid evidence to support the application of phytochemicals or dietary agents in prevention and treatment of cancer.

The precise biochemical mechanisms through which phytochemicals exert their anti-cancer effects are still being explored, as their actions are wide-ranging and complex but significant advances have been made of late in the understanding the mode of action. The most quoted cancer prevention mechanism is via their antioxidant activity, elicited either through direct free radical absorption or through induction of antioxidant enzymes such as superoxide dismutase (SOD), catalase and glutathione via a variety of molecular mechanisms. One of these mechanisms is activation of Nrf2, which switches on genes that code for antioxidant as well as detoxification enzymes.Phytochemicals, particularly the thiol class such as sulforaphane,have also been shown to inhibit the conver­sion of procarcinogens to their electrophilic, DNA damaging, chemicals.