Researchers grow breast cancer tissue from transplanted mammary stem cells

October 31, 2003

(SACRAMENTO, Calif.) -- In the battle against breast cancer, medicine may be shooting at the wrong enemy. Much like using a weed-whacker to remove the top of lawn weeds, leaving the root behind, conventional treatments that target mature, late-acting cancer cells may miss early cells that can give rise to cancer recurrences.

Mammary stem cells that grow in human breast tissue may play a pivotal role in breast cancer, according to research to be presented at the International Association for Breast Cancer Research, sponsored by UC Davis Cancer Center. By developing novel molecular therapies to target these stem cells, medicine may be able to overcome the drug resistance and relapse that can inhibit successful breast cancer treatment. Even after apparently successful treatment, currently as many as 40 percent of breast cancer patients eventually experience a recurrence of their disease.

"It's been hypothesized for some time that there are stem cells in human cancers that are capable of dividing and taking on specific functional properties that may give cancers the ability to spread more readily or to evade standard therapies," said Alexander Borowsky, a breast cancer researcher at the UC Davis Center for Comparative Medicine. "Researchers now have found some ways to identify these cells in tumors -- essentially creating a new field of cancer research."

Advances in the new field will be reported by research teams from throughout the world during the five-day meeting, which focuses on developments in the use of mouse models to study human breast cancer. Stem cells are young, unspecialized cells that have the potential to develop into a variety of different cell types.

On Tuesday afternoon, investigators from the University of Michigan Comprehensive Cancer Center in Ann Arbor will report on landmark experiments in which they successfully grew breast cancer tissue from both human and mouse mammary stem cells. The stem cells had been transplanted into the chests of specially bred laboratory mice.

"Utilizing conventional breast cancer therapies, we can produce a partial response in many women. But if we're leaving behind cells that can make the cancer return, we may be focusing on the wrong cells," said Max Wicha, director of the Michigan center. "We now have a validated new target for what we hope will be the development of more effective agents utilizing biological approaches."

In a related presentation the same afternoon, a team of investigators from Baylor University Medical School in Houston, UC San Francisco, Washington University School of Medicine in St. Louis, Mo., and Memorial Sloan Kettering Cancer Center in New York will present basic new insights into what causes stem cells to become malignant.

"Our findings, for the first time in laboratory animal models, demonstrate the differences between normal and cancer stem cells," said lead investigator Jeffrey Rosen, professor of molecular and cellular biology at Baylor University Medical School in Houston.

Ultimately, the research team hopes to be able to develop drugs that can prevent mutated stem cells from reproducing and forming tumors. According to Borowsky, the new field of cancer stem cell research could transform cancer treatment. "It will be very interesting to learn more about the properties of these cancer stem cells," he said. "How do they evade the body's natural defenses against cancer, and to what extent do they evade conventional cancer therapies? Can we fool them into differentiating into harmless, non-cancerous tissues? Can we specifically target these cells for destruction?"
The UC Davis Cancer Research Program encompasses the UC Davis Center for Comparative Medicine, a collaborative research venture of the UC Davis Schools of Medicine and Veterinary Medicine that focuses on diseases common to humans and animals, and the UC Davis Mouse Biology Program, home of the Mutant Mouse Regional Resource Center, the world's largest archive of mutant mice.

Founded in the mid 1950s, the International Association for Breast Cancer Research is an international community of scientists focused on the important issues in modern breast cancer research. The 24th IABCR Congress, devoted to preclinical research using mouse models of human breast cancer, is co-sponsored by the Office of Women's Health of the U.S. Department of Health and Human Services, the California Breast Cancer Research Program, and the National Cancer Institute's Mouse Models of Human Cancers Consortium and Specialized Programs of Research Excellence.

For information about other scientific presentations at the meeting, visit the conference Web site at

David Kaye
Feinstein Kean Healthcare

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 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