(Press-News.org) ROCHESTER, Minn. -- A mutant gene long thought to accelerate tumor growth in thyroid cancer patients actually inhibits the spread of malignant cells, showing promise for novel cancer therapies, a Mayo Clinic study has found. The findings will be presented by Mayo Clinic researcher Honey Reddi, Ph.D., at the Endocrine Society meeting in Boston.
Dr. Reddi's discovery could have widespread implications in cancer research and endocrinology. It could help oncologists sharpen the diagnosis of specific types of thyroid cancers, while leading pharmaceutical researchers toward therapeutics derived from a protein once thought to feed tumor growth.
"It's not an oncogene like everyone thought it was," Dr. Reddi says, referring to a gene with the potential to cause cancer. "We all knew what happened in the cell culture, but we said, 'That's not good enough,' so we asked, 'What would it do in mice?'"
Thyroid cancer is the sixth most common cancer in the world, and 15 to 20 percent of all thyroid cancer cases are follicular, a type that is more aggressive. Dr. Reddi's findings could aid this diagnosis and treatment for thousands of patients.
Distinguishing benign from malignant follicular thyroid cancer poses a unique challenge to oncologists. An accurate diagnosis of malignant follicular cancer cannot be made until after cancerous material is removed. That has led to countless unnecessary surgeries in patients with benign thyroid tumors. Patients who now present with non-papillary cancerous growths on thyroid cells must undergo surgery to remove the tumor — even if the cancer is benign.
Dr. Reddi's research found that the PAX8/PPARγ fusion protein, developed from a mutated fusion gene found in many follicular thyroid carcinomas, functions as a tumor suppressor by upregulating (encourages natural production of) microRNA-122 and PTEN, both naturally occurring anti-tumor agents.
PAX8/PPARγ results from the translocation of genetic material between human chromosomes 2 and 3. Previous in vitro studies of the PAX8/PPARγ protein found rapid acceleration of cell growth, which led researchers to the false interpretation that PAX8/PPARγ functioned as an oncogene, a type of mutated gene that encourages tumor propagation, Dr. Reddi says.
Mayo Clinic's in vivo animal studies show that PAX8/PPARγ upregulates the well-known anti-cancer protein PTEN, as well as microRNA-122, and likely facilitates other cancer-fighting molecules.
PAX8/PPARγ does not boost tumor progression when exposed to cancerous cells, Dr. Reddi says. Rather, its facilitation of other native anti-cancer molecules appears to outweigh the tumor propagation. Tumors grew about four times slower in mice exposed to the PAX8/PPARγ gene than those who were deprived of the protein's cancer-fighting qualities.
Among the team's goals in future research is the identification of other microRNA-like markers, which could identify a benign disease and obviate the need for immediate and unnecessary surgery.
Based on her discussions with clinicians at Mayo Clinic, Dr. Reddi says, "There are many complications from thyroid surgery, and having early detection markers could save thousands of unnecessary surgeries every year. We're just getting started and look towards a rapid translation from bench to bedside."
###
Others on the study team include Bryan McIver, M.B., Ch.B., Ph.D.; Norman Eberhardt, Ph.D.; Pranathi Madde; Dragana Milosevic; Alicia Algeciras-Schimnich, Ph.D.; and Stefan Grebe, M.D.; all of Mayo Clinic. Translation of this research to a clinical setting is being done in collaboration with Dr. Grebe. The study was funded by Mayo Clinic, the Fraternal Order of Eagles, and the National Institutes of Health. The Emslander Career Development Award supported Dr. McIver.
About Mayo Clinic
Mayo Clinic is a nonprofit worldwide leader in medical care, research and education for people from all walks of life. For more information, visit www.mayoclinic.org/about/ and www.mayoclinic.org/news.
END
When older relatives begin to lose their independence, we expect them to be treated kindly and professionally by those we entrust with their care. Unfortunately, sometimes the most vulnerable members of our population suffer at the hands of nursing home employees.
Warning Signs
According to American Psychological Association estimates, more than 2 million seniors are subjected to some form of abuse or neglect.
Knowing what indicators to look out for can help you prevent your loved ones from being exploited. Bruises, cuts and other visible injuries are perhaps the ...
In a study that included nearly 18,000 children who had cancer, with follow-up of about 25 years, the greatest excess risk associated with a subsequent primary neoplasm (a new tumor) at older than age 40 years was for digestive and genitourinary neoplasms (related to the genital or urinary tract organs), according to a study in the June 8 issue of JAMA, a theme issue on cancer. The study is being published early online to coincide with the American Society of Clinical Oncology 2011 Annual Meeting.
"Survivors of childhood cancer are at increased risk of developing subsequent ...
In a clinical trial that included nearly 80,000 women, those who received ovarian cancer screening did not have a reduced risk of death from ovarian cancer compared to women who received usual care, but did have an increase in invasive medical procedures and associated harms as a result of being screened, according to a study in the June 8 issue of JAMA, a theme issue on cancer. The study is being published early online to coincide with its presentation at the American Society of Clinical Oncology 2011 Annual Meeting.
In the United States, ovarian cancer is among the ...
A divorce can be difficult, even when there are no children present. Decisions must be made about the marital home, dividing assets, splitting mutual debts and other things. A divorce can be much more complicated for parents, however. They not only have to decide the same property settlement issues that other couples face, they must keep the best interests of their children at heart through it all when making child custody and parenting time decisions.
Child Custody Arrangements Under Oregon Law
Chapter 107 and 109 of the Oregon Revised Statutes (ORS) sets forth the ...
An analysis of data from previously published studies indicates that longer time to beginning adjuvant chemotherapy after surgery for colorectal cancer is associated with worse survival, according to a study in the June 8 issue of JAMA, a theme issue on cancer. The study is being published early online to coincide with its presentation at the American Society of Clinical Oncology 2011 Annual Meeting.
"Colorectal cancer (CRC) is the third leading cause of cancer mortality in the Western world. While surgical resection [removal] remains the cornerstone of management for ...
Among various genetic mutations for individuals with Lynch syndrome, a hereditary cancer syndrome that carries a high risk of colon cancer and an above-normal risk of other cancers, researchers have identified mutations associated with a lower cancer risk and mutations associated with an increased risk for ovarian and endometrial cancer, according to a study in the June 8 issue of JAMA, a theme issue on cancer. The study is being published early online to coincide with the American Society of Clinical Oncology 2011 Annual Meeting.
The Lynch syndrome, also known as hereditary ...
An Indiana University study that exposed older veterans with stroke to yoga produced "exciting" results as researchers explore whether this popular mind-body practice can help stroke victims cope with their increased risk for painful and even deadly falls.
The pilot study involved 19 men and one woman, average age of 66. For eight weeks, they participated in a twice weekly hour-long group yoga class taught by a yoga therapist who dramatically modified the poses to meet the veterans' needs.
A range of balance items measured by the Berg Balance Scale and Fullerton Advance ...
If passed into law, a new bill currently working its way through the U.S. Senate would increase the weight and size limits for commercial trucks on American roads. While many in the trucking industry have been vocal supporters, the legislation raises some serious concerns.
Details of the Bill
Senate Bill 747 ("S. 747"), named the Safe and Efficient Transportation Act of 2011, proposes an end to the federal moratorium on modification of current size and weight standards for commercial trucks. Today, semi size on most interstate highways is capped at 80,000 ...
(Hamilton, ON) June 4, 2011 - Additional radiation treatment improves disease free survival lessening the chance of cancer recurring in women with early breast cancer who have had breast conserving surgery (lumpectomy), interim results of a new study found. The results will be presented Monday, June 6 at the annual meeting of the American Society of Clinical Oncology.
"These results are potentially practice-changing," said Dr. Timothy J. Whelan, professor of oncology at McMaster University's Michael G. DeGroote School of Medicine and lead study investigator for the NCIC ...
An Indiana University study examining disparities in physical fitness levels between older adults who are patients of safety net community health centers (CHC) and those who are members of a medically affiliated fitness center is producing stunning results.
NiCole Keith, associate professor in the Department of Physical Education at Indiana University-Purdue University Indianapolis, said she expected the study to show similar physical fitness levels between the two groups. The findings, however, show that the fitness center participants performed significantly better ...
