Recent research published in the Journal of Clinical Investigation examined the drug Dacogen (decitabine), which was observed to target the growth of cancer and was effective in treating tumors resistant to chemotherapy. The Food and Drug Administration has approved decitabine for treating bone marrow and blood cancers
“Patients whose tumor does not respond well to chemotherapy are known to be at significantly increased risk of recurrent breast cancer and death,” expalins Judy Boughey, MD, a general surgeon at the Cancer Center at the Mayo Clinic in Rochester, Minnesota. “Therefore, our focus is to identify new treatment options for these patients.”
Breast cancer is responsible for 30 percent of new cancer diagnoses in women in the United States each year. About 1 in 8 women will be diagnosed with invasive breast cancer at some point in their lives. The majority of breast cancers are invasive, which means that the cancer spreads and grows in healthy tissues. This is in comparison to noninvasive breast cancers which remain in the lobules or the milk ducts.
For triple-negative breast cancer (TNBC), the National Breast Cancer Foundation describes this particular cancer as the cells of the tumor that do not include the three most common forms of receptors, which is the HER-2 receptor, estrogen receptors, and progesterone receptors.
Investigators have been studying the potential use for decitabine in solid tumors, however the results are more encouraging than previous trials, exapalisn Cynthia Zahnow, PhD, an associate professor of oncology at the Johns Hopkins University School of Medicine. “We [researchers at Johns Hopkins] published a paper back in 2012 showing that these low doses of these drugs do have an effect in cancer tumors,” she explains, referencing a study published in March 2012 in the journal Cancer Cell.
The study suggested that the therapy could create an anti-tumor “memory” response, and inhibit growth of cancer stem-like cells. In the Mayo research study, the researchers used living xenografts (tissue from breast tumor cells). They found that decitabine can remarkably inhibit the growth of triple-negative breast cancers, however, the response was dependent on the presence of certain critical proteins known as DNA methyl transferase proteins (DNMT), which are present in a certain subset of triple-negative breast cancers.
“If researchers can truly select patients that have high levels of DNMT and show that these drugs are more effective in them, that’s a fantastic discovery,” notes Dr. Zahnow.
Sources: Journal of Clinical Investigation