More than half of all cancers occur in developing countries including those located in Southern America and Asia. Nearly three-quarters of people in these countries are classified into low or middle-income categories. The cancer survival rates are generally one-third of the patients in the developed countries. There are 9 million new cases of cancer each year, with 4 million new cancer cases in the developed countries and 5 million in developing countries. In the next decades, cancer will be one of the leading causes of illness worldwide, and the number of new cases of various types of cancer is expected to rise to 15 million by 2025. Furthermore, cancer is predicted to be the leading cause of death by 2030. Given that cancer statistics are on the rise, and their treatments are costly, it is very crucial to find effective and economically viable methods for patients in low and middle income countries.
A systematic review of the clinical studies on curcumin use and its effectiveness in inhabiting and treating various types of cancer is carried out to obtain comprehensive information about the curcumin effects on cancer.
Turmeric is a yellow spice with a long history used both in food and medicine. It is mostly used in Thai and Asian dishes.
The main active ingredients in turmeric are curcuminoid compounds. These compounds give turmeric its distinctive yellow color. Curcumin is the compound that we know the most about.
What is Curcumin ?
Curcumin is a bright yellow chemical produced by plants of the Curcuma longa species. It is the principal curcuminoid of turmeric, a member of the ginger family, Zingiberaceae. It is sold as a herbal supplement, cosmetics ingredient, food flavoring, and food coloring.
How curcumin slows cancer growth?
Curcumin has long been used in Asian medicine to treat a variety of illnesses. Now some research suggests that curcumin may help prevent or treat cancer. Laboratory and animal research suggests that curcumin may prevent cancer, slow the spread of cancer, make chemotherapy more effective and protect healthy cells from damage by radiation therapy.
Extensive research over the past two decades suggests that curcuminoids belonging to the diferuloylmethane class of natural products, the major constituents in turmeric (Curcuma longa), interfere with multiple cell signaling pathways, which provides support for the potential role of curcumin in modulating carcinogenesis.
“Curcumin is a natural antioxidant that has anti-inflammatory benefits, as well as [possible] benefits related to slowing the aging process and preventing Alzheimer’s disease and, potentially, depression,” says Elizabeth Ann Shaw, RDN, the owner of Shaw Simple Swaps Consulting in San Diego.
Curcumin role in the prevention of cancers
Free radicals and toxic products resulting from oxidative stress play an important role in the early stages of cancer formation. Therefore, compounds that have antioxidant effects can be helpful in preventing cancer formation. Curcumin has the property of trapping free radicals and thus can play a crucial role in inhibiting the onset of cancer.
Several cellular and preclinical studies have reported that curcumin inhibits DNA damage caused by oxidative factors, such as ionizing radiation by inhibiting free radicals and active oxygen species.
The NF–kappaB (nuclear factor kappa light chain enhancer of activated B cells) is a family of highly conserved transcription factors that regulate many important cellular behaviors, in particular, inflammatory responses, cellular growth and apoptosis) plays an important role in the formation of Nitric oxide synthase and oxidative stress, and as a result causes cancer. Curcumin suppresses the onset of cancer by inhibiting NF-kappaB from formation. Curcumin was reported to be effective on liver enzymes Cytochrome p450 which has an imminent role in the oxidation and detoxification of toxins, it also inhibits the Phase I enzymes that are involved in the production of toxic metabolites and carcinogens. Furthermore, curcumin activates the Phase II enzymes, which plays a crucial role in detoxification of toxic metabolites. Curcumin prevents tumor formation and growth by inhibiting and activating these two enzymes.