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The special issue on “Phytochemicals and Cancer Chemoprevention” contains original research and review
articles is aimed to stimulate the continuous efforts to understand the identification, development and use
of phytochemicals for cancer prevention and treatment. It has been estimated that more than two-thirds of
[6]
human cancers are preventable through proper diet and lifestyle changes. In 1981, Doll and Peto reported
that 30%-40% of human cancer is preventable, and its mortality is attributed to diet. Their observations were
based on statistical and epidemiological data with major concerns on dietary factors that increase cancer
risk . Although the exact percentage is uncertain, compelling evidence from epidemiological, clinical, and
[6]
laboratory studies suggest a link between cancer risk and nutritional factors.

Several phytochemicals have been identified as bioactive agents which possess cancer preventive and
[7]
therapeutic properties. Dave et al. reviewed some well-established natural phytochemicals as cancer
chemopreventive agents, including resveratrol (grapes), epigallocatechin-3-gallate (green tea), sulforaphane
(cruciferous vegetables), anthocyanins (grapes and berries), curcumin (turmeric), silibinin (milk thistle),
and lycopene (tomatoes). As appropriately demonstrated by the genomic analysis and other methods, the
mechanistic underpinning remains variable and complex. The authors further suggest that these responses
may be mediated through indirect mechanisms, including interaction with the microbiome. In addition,
ancillary applications of the chemopreventive-agents remains worth considering, such as the management
of chemotherapy induced sequelae. Recognizing the loss of millions of cancer patients every year, it is
obvious that negating malignant metastatic conditions remains of paramount importance. In meeting these
goals, cancer chemoprevention by phytochemicals offers great promise.

The importance of phytochemicals lies in their superior properties of reducing side-effects, efficacy in
chronic conditions, cost-effectiveness, and widespread usage of natural compounds. The manuscript by
[8]
Kushwaha et al. has proposed using phytochemicals in cancer chemotherapy having a promising future.
Through in silico approach, the authors have shown that the phytochemicals present in Bulbine frutescens
(Asphodelaceae) are involved in the mitigation of anticancer drug mediated drug resistance. Through an
approach utilizing molecular docking and molecular dynamics simulation, the authors have screened 25
phytochemicals against the ABC transporter protein. The involvement of drug efflux transporters such as P-
glycoprotein, also known as ABC (ATP-binding cassette) transporters, facilitates the transport of drugs and
their metabolites across the cellular membrane of cancer cells. ABC transporter-mediated drug efflux causes
disease relapse in cancer patients and decreases the therapeutic output; therefore, it remains a putative drug
target. The authors conclude that 4’-Demethylknipholone 2’-β-D-glucopyranoside, a phytochemical present
in B. frutescens possesses remarkable anti-drug resistance properties and inhibitory potential against ABC
transporters.

[9]
Another review article published by Yeger and Mokhtari discussed the isothiocyanates family of naturally
occurring small molecules generated from the glucosinolate precursors of cruciferous vegetables. The cancer
chemopreventive roles of some key isothiocyanates such as sulforaphane, phenethylisothiocyanate, and
benzyl isothiocyanate have been studied in preclinical and clinical settings. In the review article, the authors
have presented a broader perspective on the isothiocynates, including their research on sulforaphane-
mediated cancer prevention and treatment. The authors further discussed the hormetic effects which might
affect the efficacy of these agents, and their role as anti-inflammatory molecules with insights into potential
therapeutic applications.

The review article by Grynkiewicz discussed the research on isoflavones in human health. Flavonoids are
[10]
a large family of polyphenols that include over 6000 members widely distributed in the plant kingdom.
Isoflavones, a subfamily of flavonoids, is the main focus of the review. These compounds are major