Different types of anticancer compounds possess various modes of action extracted from plant sources such as Taxus brevifolia, Catharanthus roseus, Betula alba, Cephalotaxus species, Erythroxylum previllei, Curcuma longa, and many more. Curcumin is the essential plant source that shows efficacy in cancer treatment among all these plant sources. It is the component of rhizomes of Curcuma longa L. (turmeric), extracted from the turmeric plant. Therefore, curcumin and its derivatives have gained more attention in the past decades regarding their biofunctional properties such as anti-tumour, antioxidant, and anti-inflammatory activities.
Curcuminoids are bioactive ingredients of the spice turmeric derived from the rhizomes of Curcuma longa L. (Zingiberaceae). Curcumin with a chemical structure constituting bis-α,β-unsaturated b-diketone; diferuloylmethane is the principal curcuminoid. It mainly includes around 2–5% of total turmeric content and, more often, 70%–75% of total curcuminoids of the plant.
Figure 1: Curcuminoid chemical structure
These are bioactive polyphenolics in nature, showing significant health benefits against different disorders (Gupta et al., 2013). The various pharmacological activities in these compounds are due to the ability of this molecule to interact with multiple biological targets and signalling pathways (Mohammadi et al., 2013). Hence, this evidence depicts its potency towards anticancer effects.
Curcumin in cancer treatment
Although global awareness and implementation of different therapeutic options for cancer prevention are integrated, cancer is still considered the primary cause of increasing death rates across the globe. The cancer cells are characterised by disrupting several signalling pathways involving the ones responsible for angiogenesis, proliferation, metabolism, migration, immune modulation and survival (Pentimalli et al., 2019). The use of curcumin has shown efficacy in affecting the growth of cancer cells in different ways resulting in the prevention of cancer development. Anticancer effects of curcumin are reported against several different types of cancer, including prostate cancer, breast cancer, colorectal cancer, pancreatic cancer, and head and neck cancer, both in vitro and in vivo. Also, its efficacy and safety among cancer patients have been studied by representing the anticancer activity through different mechanisms that interfere with various cellular pathways while inhibiting the production of multiple types of hormones, enzymes and related growth factors.
Curcumin has represented the anticancer properties by increasing the level of vitamin C and E to suppress the peroxidation of lipids and prevent DNA damage. Curcuminoids are known for avoiding tumour formation and enhancing tumor size reduction. It inhibits cancerous cells and metastasis of tumors by producing anti-angiogenic effects that result in apoptosis and interfere with the cell proliferation cycle (Prasad et al., 2014).
Curcumin beyond cancer treatment
Curcumin is known as one of the most active ingredients in turmeric and hence is used by researchers in determining its different benefits in certain conditions on its own. Curcumin’s anti-inflammatory and antioxidant properties have supported wound healing conditions through its antibacterial effects. It is effective in reducing the blood sugar level in type 2 diabetes, along with depicting its use in lower inflammatory markers such as tumor necrosis factor (TNF) and interleukin 6 (IL-6); it is also considered the major contributor in treating type 2 diabetes (Jain et al., 2009). The turmeric extracts enriched with curcumin-like curcuminoids effectively preserve the bone mass.
Turmeric has been a golden spice used in treating inflammation, bacterial infections and digestive issues for several years. Researchers have revealed turmeric extraction with a high concentration of curcumin. It has shown efficacy in reducing joint inflammation, cholesterol, blood sugar, and tumor, fungal and bacterial growth.
- Gupta, S. C., Patchva, S., & Aggarwal, B. B. (2013). Therapeutic roles of curcumin: lessons learned from clinical trials. The AAPS journal, 15(1), 195-218. https://doi.org/10.1208/s12248-012-9432-8
- Mohammadi, A., Sahebkar, A., Iranshahi, M., Amini, M., Khojasteh, R., Ghayour‐Mobarhan, M., & Ferns, G. A. (2013). Effects of supplementation with curcuminoids on dyslipidemia in obese patients: a randomized crossover trial. Phytotherapy Research, 27(3), 374-379. https://doi.org/10.1002/ptr.4715
- Pentimalli, F., Grelli, S., Di Daniele, N., Melino, G., & Amelio, I. (2019). Cell death pathologies: targeting death pathways and the immune system for cancer therapy. Genes & Immunity, 20(7), 539-554. https://doi.org/10.1038/s41435-018-0052-x
- Prasad, S., Gupta, S. C., Tyagi, A. K., & Aggarwal, B. B. (2014). Curcumin, a component of golden spice: from bedside to bench and back. Biotechnology advances, 32(6), 1053-1064. doi:10.1016/j.biotechadv.2014.04.004
Jain, S. K., Rains, J., Croad, J., Larson, B., & Jones, K. (2009). Curcumin supplementation lowers TNF-α, IL-6, IL-8, and MCP-1 secretion in high glucose-treated cultured monocytes and blood levels of TNF-α, IL-6, MCP-1, glucose, and glycosylated hemoglobin in diabetic rats. Antioxidants & redox signaling, 11(2), 241-249. 10.1089/ars.2008.2140