Cruciferous Vegetables: Dietary Phytochemicals for Cancer Prevention

Abstract

Relationships between diet and health have attracted attention for centuries; but links between diet and cancer have been a focus only in recent decades. The consumption of diet-containing carcinogens, including polycyclic aromatic hydrocarbons and heterocyclic amines is most closely correlated with increasing cancer risk. Epidemiological evidence strongly suggests that consumption of dietary phytochemicals found in vegetables and fruit can decrease cancer incidence. Among the various vegetables, broccoli and other cruciferous species appear most closely associated with reduced cancer risk in organs such as the colorectum, lung, prostate and breast. The protecting effects against cancer risk have been attributed, at least partly, due to their comparatively high amounts of glucosinolates, which differentiate them from other vegetables. Glucosinolates, a class of sulphurcontaining glycosides, present at substantial amounts in cruciferous vegetables, and their breakdown products such as the isothiocyanates, are believed to be responsible for their health benefits. However, the underlying mechanisms responsible for the chemopreventive effect of these compounds are likely to be manifold, possibly concerning very complex interactions, and thus difficult to fully understand. Therefore, this article provides a brief overview about the mechanism of such compounds involved in modulation of carcinogen metabolising enzyme systems.

Dietary Glucosinolates Sulforaphane, Phenethyl Isothiocyanate, Indole-3-Carbinol/3,3′-Diindolylmethane: Antioxidative Stress/Inflammation, Nrf2, Epigenetics/Epigenomics and In Vivo Cancer Chemopreventive Efficacy

“…Interestingly, prevention and/or protection from chemical carcinogens by phytochemicals present in glucosinolate-containing cruciferous vegetables is of great interest because they may provide a safe and cost-effective strategy for combating cancer [5, 6**]. In this context, numerous epidemiological and pharmacological studies have revealed that the consumption of cruciferous vegetables has substantial potential for human cancer chemoprevention [7]. …”

Indole phytoalexin derivatives induce mitochondrial-mediated apoptosis in human colorectal carcinoma cells

“…It is generally accepted that consumption of cruciferous vegetables is inversely associated with the risk for variety of cancers, including CRC[4-8]. It is believed that glucosinolates, sulfur-containing phytochemicals, and their metabolic derivatives ( e.g ., isothiocyanates) play an important function in the cancer-chemopreventive role of cruciferous plants[9]. They act through multiple mechanisms in the prevention of cancer.…”

The natural compound sulforaphene, as a novel anticancer reagent, targeting PI3K-AKT signaling pathway in lung cancer

“…This chemoprotective effect is closely related to isothiocyanates (ITCs), a group of hydrolysis products of glucosinolates, which are relatively unique in cruciferous vegetables [7, 8]. As one of the most studied ITCs, sulforaphane (4-methylsulfinybutyl isothiocyanate, SFA) was initially identified as the principal inducer of phase II enzymes [9] and has subsequently been shown to possess anticarcinogenic activities in many malignances [10–15].…”