The researchers say women who have the risk factors commonly associated with type 2 diabetes such as being overweight and insulin resistant, also have a much greater risk of being diagnosed with an advanced breast cancer.

The research due to be presented this week at a conference in Brisbane, has found that women who were overweight or had signs such as elevated blood glucose or insulin levels - were about 50 per cent more likely to be diagnosed with an advanced breast cancer tumour.

The research which was part of an international study will be presented this week to the Population Health 2008 Conference in Queensland.

Dr. Anne Cust from the University of Melbourne who was one of the collaborators on the international study says that previous research has shown a strong link between being overweight and increased breast cancer risk in post menopausal women.

Dr. Cust says this study is the first to demonstrate the influence of insulin resistance on the stage of cancer diagnosis.

Dr. Cust says women with insulin resistance or who were overweight were less likely to be diagnosed with stage 1 breast cancers but at greater risk of being diagnosed with stage 2 to 4 tumours which are larger more advanced cancers.

For the study the researchers tracked more than 60,000 Swedish women over a 20-year-period from 1985 to 2005..... all were cancer free when recruited.

Over the study period their blood was tested for glucose, insulin and other hormones associated with obesity and diabetes risk.

Dr. Cust says while it is known that being overweight and having insulin resistance is a risk factor for getting cancer, this study indicates, in the case of breast cancer, that the cancer will be more advanced.

Dr. Cust says the research findings come at a significant time when there are major public health concerns about obesity and type 2 diabetes rates.

Although the researchers experimented with up to 100 ?µmol/L of resveratrol, the suppression of DNA adducts was seen with 10 ?µmol/L... a glass of red wine contains between 9 and 28 ?µmol/L of resveratrol.

The researchers also found that resveratrol suppressed the expression of CYP1B1 and the formation of 2,3,7,8-Tetrachlorodibenzo-p-dioxin, two known risk factors for breast cancer.

Professor Rogan says resveratrol works by inducing an enzyme called quinone reductase, which reduces the estrogen metabolite back to inactive form... by making the estrogen inactive, resveratrol decreases the associated risk.

Professor Rogan says the study was conducted in laboratory cultures, and will now need to be confirmed in larger human trials.

The research is published in the current issue of Cancer Prevention Research, a journal of the American Association for Cancer Research.