Abstract
Cancer is the second most common cause of death worldwide. Many methods such as surgery, chemotherapy, radiation therapy, etc. are being used for treatment. Most patients have a combination treatment with chemotherapy along with surgery or radiotherapy or both. Chemotherapy kills cancer cells by preventing them from reproducing, growing, and spreading in the body. Recently, safer alternatives to chemotherapy have been discovered and developed, as most of the drugs used in cancer treatment have side effects and a serious impact on patient comfort. As an alternative, the phytochemicals found in daily consumed plants are attractive candidates for clinical/pre-clinical evaluation because of their higher safety. In this context, certain degradation products of glucosinolates (isothiocyanates) are promising agents for cancer prevention and treatment.
TopIntroduction
Chemopreventive agents prevent the formation of reactive carcinogens, whereas carcinogens enhance malignant transformation of initiated cells at the promotion or progression stages. Initiation, promotion, and progression are three stages of carcinogenesis (Sporn & Suh, 2002; Blagosklonny, 2005).
Diet is a remarkable factor in cancer progression and a balanced diet can decrease 40% of cancer cases (Donaldson, 2004). Several bioactive compounds from diet have been known as chemopreventive agents. These include isothiocyanates (ITCs) found in cruciferous vegetables, resveratrol found in grape seeds and red wine, catechins found in green tea, curcuminoids found in turmeric, isoflavones found in soybean or procyanidins from various fruits and nuts, and antioxidant vitamins (Scalbert et al, 2005). In cruciferous vegetables such as radish, broccoli, brussels sprouts, watercress, cabbage, cauliflower, precursors of ITCs are abundant and when the plant cell wall is disrupted by physical stress, the enzyme myrosinase cleaves the glucosinolates into biologically active ITCs. ITCs have been shown to inhibit the growth of cancer cells in different animal models, and a diet high in cruciferous vegetables is linked to a decreased cancer risk (Zhang, 2004).
There are hallmarks of cancer that cancer cells are acquired during the development, one of which is avoiding immune destruction. Cancer cells can hijack normal mechanisms of immune checkpoint control and can evade detection and be destroyed by the host’s immune system (Hanahan, 2022). Bioactive compounds have indirect antitumour effects by enhancing the immune system (Subramaniam et al., 2019). Immune system reacts to harmful stimuli, such as pathogens, damaged cells, toxic compounds, or irradiation causing inflammation (Medzhitov, 2010). Over 150 years ago Robert Virchow suggested a link between inflammation and cancer and reported that chronic inflammation can induce certain cancer types (Munn, 2017). In terms of prevention and treatment, there are now some implications (Balkwill & Mantovani, 2001). There is strong evidence that chronic inflammation initiated by chemical and physical agents, as well as different inflammatory reactions involving leukocytes and tumour cells are correlated with an elevated risk of malignancy. Cytokines and chemokines, their expression and mechanisms of action as well as their preventive and therapeutic targeting of inflammation have been the focus of research so far (Todoric et al., 2016). Grimble has found that there is an interaction between different nutrients, including those of plant origin; pro-inflammatory cytokines; and inflammation (Grimble, 1996; Grimble & Tappia, 1998).
Key Terms in this Chapter
Angiogenesis: It is a physiological process and means the formation and development of new vessels by budding from existing vessels. It is similar to vasculogenesis. Angiogenesis is an expected event in processes such as growth and development and wound healing.
Inflammation: Inflammation is a cellular (cellular), humoral (fluid) and vascular (vascular) serial vital response that living tissue gives to any living or non-living foreign factor or internal/external tissue damage. Although inflammation is normally a pathological condition, the inflammatory reaction is a physiological response of the body.
Metastasis: Metastasis is the name given to the spread of cancerous cells to other areas outside the tissue they are in, either directly or via blood-lymph vessels.
Chemoprevention: Chemoprevention refers to the administration of a drug to prevent disease or infection. For example, antibiotics can be administered to patients with impaired immune system function to prevent bacterial infections.
Carcinogen: A carcinogen is a substance that has the capacity to cause human or animal cancer. Carcinogenic agents can be of physical, chemical or biological origin.
Proliferation: It is a medical term that used the condition of cells increasing or multiplying by dividing.
Chemotherapy: Chemotherapy, which means “treatment with drugs”, is the term used for treatment using cancer drugs that mostly affect cancer cells. The drugs used for this are also called “anticancer” drugs.