Below I have copied a letter to the British Medical Journal in 2012 by a Scottish doctor whose name I did not keep. It was a response to an editorial on findings about aspirin and cancer. It may be of interest to some of our correspondents.
Re: Aspirin and cancer prevention
Reply to BMJ Editorial of 7.4.2012
ASPIRIN AND CANCER PREVENTION
Has the Medical profession accidentally stumbled onto a relatively inocuous cure for cancer?
Long term use of Aspirin, Metformin and the non selective BETA adrenergic receptor blocker Propranolol are all associated with lower cancer incidence, metastases and death.
Ref 1,2,3,4 and 5.
I believe the main mechanism linking thee drugs in inhibition of tumour Glycolysis.
You said in your Editorial of 7.4.12
“The study’s findings suggest low dose Aspirin should be considered in the treatment of some patients with cancer” and “the findings of 2 recent studies suggest daily low dose Aspirin could reduce cancer related outcomes”.
Otto Warburg found in the 1920s that cancer cells used 10 times more glucose because they get their energy from aerobic glycolysis rather than mitochondrial respiration. Switching off aerobic glycolysis and switching on mitochondrial respiration will lead to apoptosis : cancer cell death.
In your editorial you wrote that cancer metastases were reduced and that low dose Aspirin should be considered as a treatment for some cancers.
Aspirin was shown to block 5 enzymes of the glycolytic pathway.
Ref 6.
Aspirin reduced risk of adenocarcinoma with metastases at initial diagnosis and risk of metastasis on subsequent follow up of patients initially without metastases.
Ref 7
Empirically Metformin therapy gives a 31% to 37% reduction in relative risk of cancer, and improved prognosis in those found to have cancer.
Ref 8. Ref 2.
Metformin activates the AMP activated protein kinase pathway, a major sensor of the energetic status of the cell, which has been proposed as a promising therapeutic target in cancer treatment.
Metformin also inhibits the ability of Mitochondria to burn lactate and other products of glycolysis. New Scientist 17.9.2011.
Metformin delays uptake of glucose from the intestinal tract, decreases insulin resistance and inhibits hepatic and renal gluconeogenesis (Glucomet Data Sheet).
Propranolol users were significantly less likely to present with a T4 (odds ratio 0.24) or N2/N3/M1 (odds ratio 0.20). Cumulative probability of breast cancer specific mortality was significantly lower (hazard ratio = 0.19).
These results provide evidence in humans suggesting inhibiting the beta adrenergic pathway can reduce breast cancer progression and mortality.
Glycolysis is mediated through Beta 2 adrenergic receptor sites.
Ref 9
These drugs almost certainly act against cancer in other ways too, but the raw empirical data call for urgent trials of these drugs to be used together in randomised controlled trials as a cancer treatment at the very least in people otherwise offered only palliative chemotherapy.
My second question is can the medical profession do this when these drugs cost only pennies, and nearly all research is paid for by the Pharmaceutical Companies that expect to make large profits on expensive drugs.
REFERENCES
Reference 1 BMJ Editorial 7.4.2012
Aspirin & Cancer Prevention
Quote in studies Aspirin reduced the risk of cancer with distant metastases, hazard ratio 0.64.
“The study’s findings suggest low dose Aspirin should be considered in the treatment of some patients with cancer” and “the findings of 2 recent studies suggest daily low dose Aspirin could reduce cancer related outcomes”.
Reference 2
Metformin, cancer alphabet soup, and the role of epidemiology in Etiologic Research Diabetes care September 2009.
Reference 3
Metformin and Cancer Risk in Diabetic patients : A systematic review and Meta analysis Cancer Prevention and research 12th October 2010.
Reference 4
The influence of antidiabetic medications on the development and progression of prostate cancer. Cancer Epidemiology March 2012.
Reference 5
Betablockers and breast cancer mortality : a population and based study.
Journal of Clinical Oncology 2011 1st July
Reference 6
Aspirin acetylates multiple cellular proteins in HCT-116 colon cancer cells. Identification of novel targets, International Journal of Oncology 39; 1273-1283, 2011.
Reference 7
Effect of daily Aspirin on risk of cancer metastasis a study of incident cancers during randomised controlled trials. Lancet 20th March, 2012
Reference 8
Metformin in Cancer Therapy: a new perspective for an old diabetic drug published Molecular Cancer Therapy 2010 May.
Reference 9
Increased aerobic glycolysis through Beta 2 stimulation is a common mechanism involved in lactate formation during shock states. Shock October 2008 .
Competing interests: No competing interests