Metabolic Management of Cancer Disease – A Review

Abstract

The US National Cancer Institute (NCI) define cancer as a disease in which some of the body’s cells are growing uncontrollably and are also spreading to other parts of the body. Cancer disease is a major cause of deaths worldwide and from the World Health Organization (WHO) report, in year 2020 alone, cancer caused about 10 million deaths globally. Also from a WHO report, cancer disease is responsible for 1 out of every 4 to 5 deaths worldwide. Conventionally, the treatment of cancer is based on three major approaches, viz; chemical therapy, surgery and radiation therapy. But, the outcome and prognosis of the conventional treatment of cancer disease is limited in its effectiveness, so there is an urgent need for more research based therapies that can effectively treat and manage cancer disease. With that, the treatment outcome and the survival rate of cancer will likely increase. Meanwhile, the term tumour was originally applied to the swelling caused by inflammation and there are two types of tumours; benign tumours and malignant tumours. Cancer is the common term for malignant tumours and the normal progression of most malignant tumours can be divided into four phases, which are; malignant change in the target cells, growth of the changed cells, local invasion of the surrounding tissues and organs by the changed cells, and distant metastases of the changed cells to other organs. In the clinical diagnosis of cancer disease, systems have been developed to express the level of differentiation of cancer within a patient (grade) and also the extent of spread of cancer within a patient (stage). The staging of cancers is based on the; size of the primary lesion, its extent of spread to regional lymph nodes, and the presence or absence of blood-borne metastases. Two major staging systems are quite common and the first was developed by the America Joint Committee (AJC) on Cancer Staging, while the second was by the Union Internationale Contre Cancer (UICC). The UICC employs a classification called the TNM system. Normal cells use the sophisticated process of respiration for their cellular energy production, but cancer cells use the primitive process of fermentation. However, no cell in its right conditions would ever use fermentation when there is enough oxygen, especially considering that fermentation does not produce as much energy as respiration, and it also creates toxic by-products. So, fermentation is primitive and wasteful. But, surprisingly, cancer cells use fermentation even when there is plenty of oxygen around. That very observation is the basis of the explanation for the Warburg effect, which is considered to be the metabolic signature of most cancer cells. From the meta-analysis research done on cancer at the University of Cambridge, UK, it was concluded that cancer is a mitochondrial disease and one of the effective ways of managing it is through diets. So, it was concluded from the meta-analysis that cancer growth and progression can be managed through a whole body transition from fermentable metabolites made up of basically glutamine and glucose, to respiratory metabolites made up of majorly ketone bodies.