Liver cancer is the third leading cause of cancer related deaths worldwide, and what researchers thought could be the next important discovery for the field, might be the exact opposite.

A team of researchers discovered that when they blocked a particular metabolic process in mice, a treatment which was expected to limit tumour growth, they actually doubled the number of tumours.

"Our discovery was completely counterintuitive, but it clearly indicates that any treatment of liver cancer with these drugs in the future should be approached with caution, as there could be unanticipated consequences," said Kyle Hoehn from the University of New South Wales (UNSW).

The scientists investigated a known treatment that blocks a metabolic process called lipogenesis, which turns a molecule in the body called Acetyl-CoA into fatty acids.

"Many people suspect an Achilles' heel of liver cancer is a metabolic process in cells called lipogenesis, which converts sugars into fats," said Hoehn.

"This fat production is thought to play an important role in helping cancer cells proliferate."

So the UNSW researchers blocked this pathway in the liver cells of mice – hoping to halt the growth of cancer cells.

But this was not to be. Rather than halt the tumour cells from growing, the mice ended up with twice as many tumours than the controls.

"The results were very surprising," says Hoehn.

"In blocking lipogenesis, we actually improved the cells' antioxidant defence system. This basically enabled the damaged, precancerous cells to survive."

So what's happening here? Well the team found that the cancer cells were very quick to find ways around the missing fat. They were able to steal more fat from the bloodstream, and use the fat they did have more efficiently.

"Cancer cells always seem to have a workaround," says Hoehn. "They're smart little bastards."

But rather than this being a bad thing, knowing this occurs means that researchers can look into other avenues for stopping cancer growth and they don't have to waste resources on a dead end.

Plus, the researchers have found some new targets – the mechanism driving the antioxidant system and fat uptake of the cancer cells.

We're looking forward to seeing what comes next.

The research has been published in Nature Communications.

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