Hormones Matter TM

Breast Cancer Breakthroughs:: Epigenetic, HER2 Positive, Endocrine Resistant

April 10, 2012  |  Amy Sandberg


Three recently released studies offer hope for the treatment of breast cancer:

Scientists reprogram cancer cells with low doses of epigenetic drugs

Researchers at the Johns Hopkins Kimmel Cancer Center have discovered that two drugs once considered too toxic for human cancer treatment could, in low doses, cause antitumor responses in breast, lung, and colon cancers. The researchers said the drugs also were found to take aim at a cancer stem cells, which evade most cancer drugs and cause recurrence and spread.

Low doses of both drugs are approved by the U.S. Food and Drug Administration for the treatment of MDS and chronic myelomonocytic leukemia. Clinical trials in breast and lung cancer have begun in patients with advanced disease, and trials in colon cancer are planned.

Important finding in treatment if endocrine resistant breast cancer cells

A new study shows that using estrogen and a new class of agents known as c-Src inhibitors, cancel each other out. TA research team at The Georgetown Lombardi Center was testing whether a combination of estrogen and PP2, an inhibitor of c-Src used in laboratory experiments, could work synergistically to destroy breast cancer cells that no longer responded to endocrine therapy. Clinical studies have shown that about 30 percent of endocrine resistant breast tumors respond to low doses of estrogen. The Georgetown Lombardi study was designed to see if using PP2 with estrogen could produce a stronger therapeutic outcome.

These findings suggested that using a c-Src inhibitor alone may offer another treatment option to estrogen-receptor-positive breast cancer patients whose tumor no longer responds to tamoxifen or aromatase inhibitors. The study concluded, however, that the two drugs should not be used together in resistant cancers, as the produce not more, but less, of a killing effect on the cancer cells.

Roche drug shows positive results in treatment of HER2-positive metastatic breast cancer

A recent phase III clinical study conducted at Roche labs showed treatment with an investigational anti-body drug conjugate (ADC) significantly extended the time people with HER2-positive metastatic breast cancer lived without their disease getting worse.  The study enrolled people with HER2-positive metastatic breast cancer who had previously received treatment with chemotherapy.