  Phytochemicals are plant-derived secondary metabolites, which may exert many
biological activities in humans, including anticancer properties. Although
recent findings appear to support their role in cancer prevention and
treatment, this issue is still controversial. Anti-cancer activity of
phytochemicals mainly depends on their multi-target mechanism of action,
including antimutagenic, antioxidant and antiproliferative activities.
Furthermore, they may modulate the host immune response to cancer, reducing
inflammatory microenvironment and enhancing lymphocyte onco-surveillance. Since
carcinogenesis is multi-factorial and involves several signaling pathways,
multi-targeted agents as phytochemicals may represent promising anticancer
compounds. This narrative review aims to analyze the current literature on
phytochemicals highlighting their specific targets on carcinogenic molecular
pathways and their chemopreventive role. A full comprehension of their activity
at molecular and cellular levels will contribute for a better understanding of
phytochemical clinical efficacy, thus promoting the identification of new
effective plant-derived therapeutics.
