Drug developed at UC Davis may prevent breast cancer, treat post-menopausal vaginal atrophy

November 02, 2005

(SACRAMENTO, Calif.) -- A tamoxifen-like drug developed by UC Davis and Finnish researchers, now in clinical testing as a treatment for vaginal atrophy, may also help to prevent breast cancer, two preliminary studies suggest.

The studies, based on research in a mouse model of human breast cancer, will be published in the November issue of the Journal of Steroid Biochemistry and Molecular Biology and the December issue of Breast Cancer Research.

"These reports indicate that prevention of breast cancer may be another benefit of the use of ospemifine," said Michael W. DeGregorio, a professor of medicine at UC Davis. "The findings are very encouraging."

DeGregorio is senior author of the November article and a contributing author of the December paper. He has spent the last 20 years developing ospemifene in collaboration with Risto Lammintausta, managing director of Hormos Medical Corp. in Turku, Finland.

Ospemifene is now being developed by QuatRx Pharmaceuticals, an Ann Arbor, Mich.-based biopharmaceutical company that recently merged with Hormos Medical Corp. The drug is expected to enter Phase 3 clinical testing in the United States early next year for the treatment of vaginal atrophy, a common condition among postmenopausal women.

Ospemifene is one of a class of drugs called selective estrogen receptor modulators. The well-known agent tamoxifen, used to prevent breast cancer in women at high risk for the disease, and raloxifen, currently used to prevent bone fractures in women with osteoporosis, belong to the same class.

In the Journal of Steroid Biochemistry and Molecular Biology, DeGregorio and his colleagues at UC Davis compared the ability of ospemifene, tamoxifen and raloxifen to inhibit breast cancer in mice exposed to a carcinogen. Ospemifene and tamoxifen both inhibited breast cancer development: Mice in the ospemifene group were 95 percent less likely than mice in the control group to develop breast cancer. Raloxifen had no such effect. The study is available online in advance of its publication in print at www.sciencedirect.com.

The second study, led by Jeffrey P. Gregg, an associate professor of pathology and laboratory medicine at UC Davis, reports that in a mouse model, both tamoxifen and ospemifene inhibited the growth and progression of pre-malignant breast lesions that closely resemble human ductal carcinomas in situ. Both these agents decreased the growth of the lesions by reducing the proliferation rate of the precancerous cells.

The article is available online in advance of its print publication date at www.breast-cancer-research.com.

While similar, tamoxifen, raloxifen and ospemifine have variations in chemical structure that give them unique therapeutic profiles. For example, raloxifen can prevent bone fractures, but it can also cause hot flashes, insomnia and blood clots. Tamoxifen can decrease a high-risk woman's odds of developing breast cancer by half, but the drug also increases the risk of endometrial cancer and can cause the same side effects as raloxifen.

In clinical tests so far, ospemifene appears to have a unique estrogen-like effect on the vagina, yet a neutral effect on the endometrium, or lining of the uterus, and no aggravation or initiation of hot flashes. Results of the Phase 1 and Phase 2 tests, conducted in postmenopausal women in Finland, appear in the journal Menopause in September 2003 and March 2005.

"Dr. Lammintausta and I worked for many years to find a drug that would have beneficial effects in healthy, postmenopausal women but be absolutely safe," said DeGregorio. "We're gratified that this seems to be the case."

Decreased estrogen levels can lead to a thinner, less elastic and more fragile vaginal lining. Known as vaginal atrophy, the problem affects 10 to 40 percent of post-menopausal women. Symptoms may include dryness, itching, burning, irritation, a feeling of pressure, and pain or light bleeding with sex. Estrogen creams, rings, patches or oral supplements are often prescribed to treat vaginal atrophy.
-end-
UC Davis Cancer Center is the only National Cancer Institute-designated cancer center serving the Central Valley and inland Northern California, a region the size of Pennsylvania. Its cancer research program is made up of 180 scientists on three campuses: the UC Davis Medical Center campus in Sacramento, the UC Davis main campus in Davis, Calif., and the Lawrence Livermore National Laboratory in Livermore, Calif.

Media Contact:
Claudia Morain, UC Davis Cancer Center: (916) 734-9023
E-mail: claudia.morain@ucdmc.ucdavis.edu

Public Affairs
UC Davis Health System
4900 Broadway, Suite 1200
Sacramento, CA 95820
Phone: (916) 734-9040
FAX: (916) 734-9066
E-mail: publicaffairs@ucdmc.ucdavis.edu
Web address: http://www.ucdmc.ucdavis.edu/newsroom/

University of California - Davis Health System

Related Breast Cancer Articles from Brightsurf:

Oncotarget: IGF2 expression in breast cancer tumors and in breast cancer cells
The Oncotarget authors propose that methylation of DVDMR represents a novel epigenetic biomarker that determines the levels of IGF2 protein expression in breast cancer.

Breast cancer: AI predicts which pre-malignant breast lesions will progress to advanced cancer
New research at Case Western Reserve University in Cleveland, Ohio, could help better determine which patients diagnosed with the pre-malignant breast cancer commonly as stage 0 are likely to progress to invasive breast cancer and therefore might benefit from additional therapy over and above surgery alone.

Partial breast irradiation effective treatment option for low-risk breast cancer
Partial breast irradiation produces similar long-term survival rates and risk for recurrence compared with whole breast irradiation for many women with low-risk, early stage breast cancer, according to new clinical data from a national clinical trial involving researchers from The Ohio State University Comprehensive Cancer Center - Arthur G.

Breast screening linked to 60 per cent lower risk of breast cancer death in first 10 years
Women who take part in breast screening have a significantly greater benefit from treatments than those who are not screened, according to a study of more than 50,000 women.

More clues revealed in link between normal breast changes and invasive breast cancer
A research team, led by investigators from Georgetown Lombardi Comprehensive Cancer Center, details how a natural and dramatic process -- changes in mammary glands to accommodate breastfeeding -- uses a molecular process believed to contribute to survival of pre-malignant breast cells.

Breast tissue tumor suppressor PTEN: A potential Achilles heel for breast cancer cells
A highly collaborative team of researchers at the Medical University of South Carolina and Ohio State University report in Nature Communications that they have identified a novel pathway for connective tissue PTEN in breast cancer cell response to radiotherapy.

Computers equal radiologists in assessing breast density and associated breast cancer risk
Automated breast-density evaluation was just as accurate in predicting women's risk of breast cancer, found and not found by mammography, as subjective evaluation done by radiologists, in a study led by researchers at UC San Francisco and Mayo Clinic.

Blood test can effectively rule out breast cancer, regardless of breast density
A new study published in PLOS ONE demonstrates that Videssa® Breast, a multi-protein biomarker blood test for breast cancer, is unaffected by breast density and can reliably rule out breast cancer in women with both dense and non-dense breast tissue.

Study shows influence of surgeons on likelihood of removal of healthy breast after breast cancer dia
Attending surgeons can have a strong influence on whether a patient undergoes contralateral prophylactic mastectomy after a diagnosis of breast cancer, according to a study published by JAMA Surgery.

Young breast cancer patients undergoing breast conserving surgery see improved prognosis
A new analysis indicates that breast cancer prognoses have improved over time in young women treated with breast conserving surgery.

Read More: Breast Cancer News and Breast Cancer Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.