Hormone test predicts ovarian function after chemotherapy for breast cancer

ScienceDaily (June 5, 2011) — A test that shows how many eggs a woman has in her ovaries may help young women with breast cancer know what their reproductive function will be after chemotherapy, a new study finds.

See Also:Health & MedicineWomen's HealthBreast CancerLung CancerMenopauseOvarian CancerColon CancerReferenceMenopauseHysterectomyOvarian cancerInfertility

The results are being presented at The Endocrine Society's 93rd Annual Meeting in Boston.

Called the anti-Mullerian hormone (AMH) test, this blood test measures levels of an ovarian hormone that reflects the size of the ovarian reserve, or remaining egg supply. Currently, doctors use it to quantify a woman's ovarian reserve before in vitro fertilization treatments. Now researchers from Scotland have found that measurement of AMH indicates how likely it will be for a woman to still have eggs in her ovaries after chemotherapy, which can often damage a woman's eggs and cause infertility.

"Future reproductive function is a concern for many young women with cancer," said lead investigator Richard Anderson, MD, PhD, professor of clinical reproductive science at the University of Edinburgh. "This test will be of benefit to women with newly diagnosed cancer to help decide whether they need to take steps to preserve their fertility."

In the U.S. alone, breast cancer is diagnosed in more than 25,000 women younger than 45 each year, according to the American Cancer Society.

For this study, Anderson and his colleagues recruited 50 premenopausal women, ages 29 to 51, who had just received a diagnosis of early breast cancer. All women had normal menstrual cycles and were asked to keep a daily record of their menstrual cycle, as an index of ovarian activity, during the two years of the study. Before the women started chemotherapy, they gave blood samples for AMH testing. They again had AMH tests one and two years after starting treatment.

Before chemotherapy the median AMH level was 0.4 nanograms per milliliter (ng/mL). After cancer treatment the AMH level fell rapidly, becoming undetectable (below 0.16 ng/mL) in 68 percent of the women after one cycle of chemotherapy, the authors reported. By one-year follow-up, 11 women withdrew from the study, mostly because of cancer recurrence, Anderson said. Menstrual records were available for 39 women at one year and for 29 women at two years.

A low AMH measurement before treatment correlated well with amenorrhea, or absence of menstruation, after treatment. Women whose AMH before treatment was low (below 0.4 ng/mL) were 16 times likelier to have stopped menstruating after chemotherapy than women with a high pretreatment AMH value, Anderson said. The odds of losing ovarian function remained higher even after statistical analysis controlled for increasing age, which tends to lower AMH levels. Women whose AMH before chemotherapy exceeded 0.92 ng/mL were reportedly almost five times more likely to continue menstruating after treatment.

"Our data suggest that the AMH test, taken before cancer treatment, can help individualize a woman's infertility risk after chemotherapy for breast cancer," Anderson said.

He added that results of this study, which was funded by the U.K. Medical Research Council, are likely to apply to other types of cancer as well.

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Hormone precursor inhibits brain inflammation: Molecule moderates condition linked to neurodegenerative diseases

ScienceDaily (May 15, 2011) — Researchers at the University of California, San Diego School of Medicine have discovered a steroid hormone that inhibits inflammation in the brain. The findings, to be published in the May 13 issue of the journal Cell, have implications for understanding the exaggerated inflammatory responses that are characteristic features of numerous neurodegenerative diseases.

See Also:Health & MedicineImmune SystemCrohn's DiseaseHormone DisordersMind & BrainDisorders and SyndromesAlzheimer'sParkinson'sReferenceMyelinInflammationNatural killer cellAstrocyte

The discovery that the steroid hormone ADIOL, (5-androsten-3Β-17Β-diol), a precursor of androgens and estrogens, modulates inflammation induced by microglia cells could eventually lead to new treatments for patients with neurodegenerative conditions in which inflammation plays a pathogenic role. In addition, levels of ADIOL in blood or other body fluids might be useful for predicting risk or responses to drugs that mimic its actions.

The senior author of the paper is Christopher Glass, MD, PhD, professor of the department of cellular and molecular medicine and the department of medicine. Lead author is Kaoru Saijo, MD, PhD, and an associate project scientist in the Glass lab.

Though neurons get the headlines, they thrive only with the support of other cell types, among them microglia and astrocyte cells. Microglial cells help the central nervous system respond to infection and injury. Under normal conditions, they exist in a resting state, quietly but constantly surveying their surrounding environment for tell-tale indications of microbial invasion or tissue damage. Once detected, microglia initiate an inflammatory response, kick-starting immune system and tissue repair processes. Astrocytes amplify the immune reaction launched by microglia.

The microglia-astrocyte activation is vital to an effective immune response and damage repair, but if the resulting inflammation induced by these cells is not controlled or goes on too long, it can result in damage and death to neurons. Inflammation run amok is linked to many neurodegenerative diseases, such as Parkinson's disease, HIV-associated dementia, Alzheimer's disease and amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease), and some inflammatory diseases like multiple sclerosis (MS).

The new findings suggest that in healthy brains, microglia inflammation is modulated by the production of the steroid hormone ADIOL, which instructs support cells to calm down and return to their quiescent state. ADIOL works by binding to a transcription factor called estrogen receptor Β, which gets its name because of its similarity to estrogen receptor Β and its ability to bind to the female sex hormone estrogen. Unexpectedly, while ADIOL binding causes estrogen receptor α to execute an anti-inflammatory set of instructions to microglia and astrocytes, estrogen binding does not. Because of this, estrogens can actually antagonize the anti-inflammatory actions of ADIOL.

Glass and Saijo made their discovery based upon initial studies with John Katzenellenbogen, PhD, at the University of Illinois, Urbana-Champaign. Kaztenellenbogen's laboratory developed a number of synthetic small molecules that could bind very tightly and specifically to estrogen receptor .

Saijo at UC San Diego tested each of these compounds and found that some were potent inhibitors of inflammatory responses of microglia and astrocytes, while others were not. When one of these compounds was tested in vivo, it was found to strongly inhibit inflammation in the brain and to induce remission in a mouse model of multiple sclerosis.

Although estrogen itself can be neuroprotective, its lack of ability to induce the anti-inflammatory activity of estrogen receptor  led to a search for endogenous or internal molecules that might have similar activities to the synthetic compounds. Saijo worked with Andrew Li, MD, assistant adjunct professor of medicine at UC San Diego, to ultimately identify ADIOL as the endogenous regulator of estrogen receptor  activity. Notably, Saijo and Li found that the amount of ADIOL that could be produced by microglia was regulated by signals that control the magnitude and duration of inflammatory responses

"We think it possible that mutations in the genes encoding the key enzymes for the generation of ADIOL, or their inappropriate down-regulation, could contribute to pathological forms of inflammation," Glass said.

These findings raise the possibility that women are more susceptible to certain inflammatory diseases, such as MS, because their higher levels of estrogens potentially antagonize the anti-inflammatory actions of ADIOL in the brain. A similar argument might also help explain some of the adverse effects of estrogen administration on the brain in post-menopausal women.

Glass noted, however, that much research remains to be done. The precise relationship between brain inflammation and neurodegenerative disease, for example, is not fully understood. Similarly, it's not known whether people naturally produce different amounts of ADIOL. And researchers have only identified the ADIOL-estrogen connection in an MS mouse model. Glass said he and colleagues will next look at animal models for Alzheimer's, Parkinson's and HIV-dementia.

Co-authors of the study include Jana G. Collier, UCSD Department of Cellular and Molecular Medicine.

Funding for this study was provided by the National Institutes of Health.

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