A US-based breast cancer researcher has returned to her alma mater, NUI Galway, to receive an award for her scientific work over the past 20 years.
Prof Orla Conneely, who attended NUI at both undergraduate and postgraduate level between 1977 and 1983, and is now based at Baylor College of Medicine, Texas, has spent the past 17 years studying the steroid hormone, progesterone.
She said she was flattered by the Medtronic Vascular Award for Health Care and Medical Science and particularly pleased to be returning to NUI Galway.
Since joining the department of molecular and cellular biology in Baylor College, she has maintained close links with NUI Galway. "A long grapevine of students and trainees have come over to work in my lab and with the chairman of my department," she said.
Prof Conneely and her team have focused on defining progesterone's role in the development of the breasts, and particularly its role in breast cancer, by looking at the mechanism by which the hormone is recognised by, and transported into, body cells.
The naturally high levels of progesterone and the female sex hormone, oestrogen, in early pregnancy have a really remarkable protective effect against breast cancer, said Prof Conneely.
However, research has shown that exposure to similarly high levels of these hormones later in life has a completely different effect - causing, not preventing, breast cancer. This increased risk prompted the premature ending of one of the largest studies into the effect of hormone replacement therapy (HRT) in 2002.
HRT is based on either artificial progesterone and the female sex hormone, oestrogen, or oestrogen alone.
"The main reason women go on HRT is to prevent osteoporosis, hot flushes and memory loss, but continued exposure enhances the chances of breast cancer," Prof Conneely said.
Many women who give up HRT to reduce their chances of breast cancer are back on it in six months' time because of a desire to minimise their other post-menopausal symptoms, she said.
Prof Conneely's team are hoping their research work will help generate new progesterone- type drugs which mimic the beneficial effects of the hormone but eliminate the adverse effects.
Since the 1980s they have been looking at the so-called progesterone receptor, which initiates the hormone's effect on the body. In 1986 Prof Conneely's team was first to clone the gene for this receptor. This led to their discovery that the receptor is made up of two molecules, named progesterone receptor A and B. Each of these molecules has a distinct role in mediating responses to progesterone in body tissue.
More recently, Prof Conneely and her team have used "gene knockout technology" in mice in which mutated forms of the receptors are studied to define their roles in breast cancer development more clearly. By using models on mice they have found one of these molecules is far more potent in the breast than the other. The idea is to get molecular markers so one can tailor therapies.
She said the results of her team's work could be clinically available in a matter of years. Their work has opened the area of progesterone action, she said. "We have cloned the receptors and made models which can be used for drug screening."
Breast cancer rates are pretty steady with about one in eight getting the cancer, she said. Diagnosis is much better, however, and when lesions are identified early, 85 per cent of patients have more than five years remission.