Diet and exercise can suppress cancer growth

It is well known that a healthy diet and regular exercise can help to ward off cancer, but did you know they can also suppress the disease once it has begun?

The IDH1 gene mutation is a nasty mutation that reprograms the cell and is commonly found in the blood cancer, acute myeloid leukaemia, bone cancer called chondrosarcoma, bile duct cancer and low-grade glioma, a type of brain cancer. Researchers from the South Australian Health and Medical Research Institute (SAHMRI) and the University of Adelaide, working in collaboration with Stanford University, have now shown that cancers with IDH1 gene mutations can’t grow without lipids — a group of naturally occurring molecules (fats) contained in various foods such as butter and ice cream.

“Unlike other tumours [which feed on sugars], cancers with IDH1 mutations are addicted to lipids — they need to eat them and they need to make them from scratch,” said study leader Dr Daniel Thomas.

“We replicated the results in a range of cancer types, comparing a regular diet with one that was completely fat-free and were surprised to find tumours with IDH1 were stopped in their tracks when starved of lipids.”

The research has been published in the journal Cancer Discovery, and opens the door for long-term patient studies that would allow researchers to prove definitively if a diet low in lipids or lipid-lowering drugs can stop these tumours growing.

“More work needs to be done to substantiate our findings in humans long term, but for anyone with an IDH1 mutant cancer … our research suggests erring on the side of caution by avoiding foods that are high in saturated fats,” Thomas said.

“We’re quickly learning every little bit counts to achieve remission and improve survivorship without excessive chemotherapy.”

Meanwhile, a separate study from Edith Cowan University (ECU) has revealed how exercise can be beneficial to cancer patients — even when the cancer is advanced.

Previous work from ECU’s Exercise Medicine Research Institute (EMRI) showed that men with advanced prostate cancer can change the chemical environment of their body over six months of exercise training to suppress growth of cancer cells. The team observed increased levels of proteins called ‘myokines’, which are produced by skeletal muscles and can suppress tumour growth and even help actively fight cancerous cells by stimulating a range of anticancer processes in the body.

But a new EMRI study, published in the journal Prostate Cancer and Prostatic Diseases, has shown a single bout of exercise can elevate myokines even further and induce additional cancer suppression. This exercise-induced medicine occurs even in patients with incurable, advanced cancer where the disease has well and truly taken hold.

Nine patients with late-stage prostate cancer performed 34 minutes of high-intensity exercise on a stationary cycle, with blood serum collected immediately before and after, and then again 30 minutes post-workout. The team found the serum obtained immediately after this ‘dose’ of exercise contained elevated levels of anticancer myokines resulting in suppressed growth of prostate cancer cells in vitro by around 17%. Serum myokine levels and cancer suppression returned to baseline after 30 minutes.

“We report for the first time ever that men with advanced prostate cancer are able to produce an acute elevation in anticancer molecules called myokines in response to a single bout of vigorous exercise,” said EMRI researcher and study supervisor Professor Rob Newton.

“This is helping us to understand why patients with cancer who exercise exhibit slower disease progression and survive for longer.

“These patients are palliative, so there is no cure and they will eventually succumb; however, there is evidence that exercise will extend survival.”

Newton said while there is much research still to be done, the results of this study could help shape the advice given to cancer patients immediately.

“The optimal dose of exercise is not yet known, but it is likely to be 20-plus minutes each day and must include resistance training to grow the muscles, increase the size and capacity of the internal pharmacy, and stimulate the myokine production,” he said.

“This study provides strong evidence for the recommendation patients with prostate cancer, and likely anybody with any cancer type, should perform exercise most days, if not every day, to maintain a chemical environment within their body which is suppressive of cancer cell proliferation.”

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