Curry kills cancer cells

A molecule found in a curry ingredient can kill oesophageal cancer cells in the laboratory, suggesting it might be developed as an anti-cancer treatment, scientists said on Wednesday. -- PHOTO: AP

LONDON - A MOLECULE found in a curry ingredient can kill oesophageal cancer cells in the laboratory, suggesting it might be developed as an anti-cancer treatment, scientists said on Wednesday.

Researchers at the Cork Cancer Research Centre in Ireland treated oesophageal cancer cells with curcumin - a chemical found in the spice turmeric, which gives curries a distinctive yellow colour - and found it started to kill cancer cells within 24 hours. The cells also began to digest themselves, they said in a study published in the British Journal of Cancer.

Previous scientific studies have suggested curcumin can suppress tumours and that people who eat lots of curry may be less prone to the disease, although curcumin loses its anti-cancer attributes quickly when ingested. But Sharon McKenna, lead author of the Irish study, said her study suggested a potential for scientists to develop curcumin as an anti-cancer drug to treat oesophageal cancer.

Cancers of the oesophagus kill more than 500,000 people across the world each year. The tumours are especially deadly, with five-year survival rates of just 12 to 31 per cent. Ms McKenna said the study showed curcumin caused the cancer cells to die 'using an unexpected system of cell messages'.

Normally, faulty cells die by committing programmed suicide, or apoptosis, which occurs when proteins called caspases are 'switched on' in cells, the researchers said.

But these cells showed no evidence of suicide, and the addition of a molecule that inhibits caspases and stops this 'switch being flicked' made no difference to the number of cells that died, suggesting curcumin attacked the cancer cells using an alternative cell signalling system. -- REUTERS

Coffee may halt liver disease

WASHINGTON - RESEARCHERS in the United States have found another good reason to go to the local espresso bar: several cups of coffee a day could halt the progression of liver disease, a study showed on Wednesday.

Sufferers of chronic hepatitis C and advanced liver disease who drank three or more cups of coffee per day slashed their risk of the disease progressing by 53 per cent compared to patients who drank no coffee, the study led by Neal Freedman of the US National Cancer Institute (NCI) showed.

For the study, 766 participants enrolled in the Hepatitis C Antiviral Long-Term Treatment against Cirrhosis (HALT-C) trial - all of whom had hepatitis C which had not responded to treatment with anti-viral drugs - were asked to report how many cups of coffee they drank every day.

The patients were seen every three months during the 3.8-year study and liver biopsies were taken at 1.5 and 3.5 five years to determine the progression of liver disease.

'We observed an inverse association between coffee intake and liver disease progression,' meaning patients who drank three or more cups of java were less likely to see their liver disease worsen than non-drinkers, wrote the authors of the study, which will be published in the November issue of Hepatology.

Even caffeine, the chemical that gives a cup of coffee its oomph, came under the spotlight, having been found in previous studies to inhibit liver cancer in rats, but drinking black or green tea had little impact on the progression of liver disease, although there were few tea drinkers in the study. -- AFP

Growing doubts about HIV vaccine

Doubts have been raised about the reliability of a trial suggesting success for a vaccine against HIV.

In the large-scale trial in Thailand, a combination of vaccines seemed to give volunteers a protective effect of 31%.

The US military and Thai government, who co-sponsored the trial, said the effect was not caused by random chance but was statistically significant.

But new data, being published at a conference in Paris on Tuesday, is believed to question that assertion.

It was the world's largest clinical trial of a HIV vaccine - involving 16,000 people in Thailand aged between 18 and 30.

Among the 8,000 volunteers who had been given the combination of vaccines, 51 had gone on to become infected with the virus.

Of the group given a placebo, there were 74 positive cases.

The numbers were small, but according to Seth Berkley of the International Aids Vaccine Initiative, the results were "exciting news and a significant scientific achievement".

He said: "Now we have got a vaccine candidate that appears to show a protective effect in humans, albeit partially."

Lack of detail

But there were concerns as well. Researchers were not able to indicate just how the vaccines were working.

And, as more data was given to scientists, the claims about statistical significance began to look increasingly shaky.

Gus Cairns, who works with UK HIV information charity NAM, said: "This particular study was in the awkward position of producing a result that was only just statistically significant.

"This means there was a one in 26 chance that the results could be due to pure chance - and that this may not reflect anything at all.

"That's difficult. And there is also subset analysis of this study that if you only look at the people who strictly adhered to the protocol - ie took all their vaccine doses - then it becomes not statistically significant."

The problem is that the initial figures given for the numbers infected included all those who got HIV once the trial started, including those who got it in the course of the six-month regime of injections.

But if these were excluded, as they would be in many trials, then the numbers change - and so do the claims of a protective effect.

Study power reduced

These details have been substantiated by the US military HIV research programme.

In an update to the study, they indicated that if you looked at the data in this way, it does not reach statistical significance and the study's power is reduced.

Researchers are expected to give a more detailed breakdown at the Global HIV vaccines meeting in Paris.

Many scientists have been upset that the initial information about the trial came out via a press conference, rather than via a peer reviewed journal.

But according to Dr Aland Bernstein, executive director of the Global HIV vaccine enterprise, the issue of how the information came out does not matter.

"At the end of the day what matters to me is the long run. If that work doesn't hold up that's fine, we'll hear no more of it.

"If it holds up, and we'll only know that over the weeks and months ahead, then it is an important contribution - and whether we heard those results on 24 September or 24 October it doesn't matter in the long run."