MHow the gladiatorial battle between cells and tumours could change the way we treat cancer.

A discovery about the way healthy cells and tumours do battle in the body could open up completely new strategies for tackling cancer, it was claimed today.
Scientists showed for the first time that normal and cancerous cells in mammals engage in deadly gladiatorial contests.
The losers are killed by a process of induced biological suicide called apoptosis.

New knowledge: Cancer cells such as these were killed off by healthy cells, the research showed

Which it will be - healthy or tumour cells - is decided by genes and proteins.
If the balance is in favour of the cancer cells, they will cut a swathe through the healthy cells around them and spread. However, if the healthy cells get the upper hand, they will surround and eliminate the cancer cells.Although 'cell wars' of this kind have been seen before in fruit flies, scientists did not know until now that they also occurred in mammals - presumably including humans.
In future, it may be possible to 'tip the balance' so that healthy cells win in the struggle with cancer, experts believe.Dr Yasuyuki Fujita, who led the Medical Research Council team at University College London, said: 'This is the first time that we have seen cancer cells being killed simply by being surrounded by healthy cells.
'If we can build on this knowledge and improve our understanding of how this happens, in the future we may be able to find a way to enhance this ability and develop a totally new way of preventing and treating cancer.'The research, reported today in the online journal Public Library of Science (PLoS) Biology, has implications for treating common solid tumours of the sort that form in the breast, prostate, lung, stomach and bowel.The scientists carried out experiments on laboratory-cultured dog kidney cells, and identified two key proteins that helped determine the outcome of the contest between 'good' and 'bad' cells.Cancer cells that lacked the proteins, called Lgl and Mahjong - after the Chinese board game - were likely to end up the losers.
The mutant cells underwent cell suicide when they were surrounded by cells in which the proteins were active.
In cells without Mahjong, over-producing Lgl did not prevent apoptosis. But the same was not true in reverse - cells missing Lgl did not self-destruct when they had a surfeit of Mahjong.
The effects were thought to involve a well-known cell-signalling pathway called JNK, which is known to be linked to cancer. JNK signalling was raised in both Lgl and Mahjong mutants.
The scientists wrote: 'The demonstration of cell competition in mammalian tissues is an exciting step forward into understanding the interaction between carcinogenic cells and their surrounds.
'These findings identify Mahjong and Lgl as important proteins that can decide whether a cell is destined to survive that competition.
'Influencing who wins when cells compete may yield novel therapies for treatment of human cancers if researchers can develop interventions to swing the balance of power back toward normal cells.'

2009/03/16 the Daily and Sunday Express