Progesterone inhibits tumor growth — new study

Virginia Hopkins Health Watch

A new study from Emory University published in the journal Molecular Medicine shows that high doses of progesterone inhibited the growth of neuroblastoma tumors in mice without killing healthy cells. Neuroblastoma is a cancer that develops from nerve tissue, and is the most common cancer in small children. The Emory researchers are investigating whether progesterone will also stop the growth of glioblastomas and astrocytoma, both brain cancers.

The senior author of the study is Dr. Donald Stein, who pioneered the use of progesterone for brain injuries. The Emory team was working on the problem of how to make progesterone more effective when they discovered that while progesterone was protecting healthy neurons from stress effects it also killed cells in a cancer line. When they investigated this effect in mice, they found that over eight days progesterone cut tumor growth by 50 percent, without toxicity. They explain that, “High-dose P4 [progesterone] inhibited tumor growth by suppressing cell proliferation and inducing apoptosis…” Apoptosis is programmed cell death, and a hallmark of cancer cells is that they don’t die when they’re supposed to. Progesterone also signals cells to differentiate, or develop into specific types of cells. Another hallmark of cancer cells is that they don’t differentiate.

In the book What Your Doctor May Not Tell You about Breast Cancer (2002, Lee, Zava Hopkins) we pointed out that these same effects of progesterone can prevent breast cancer. We can only hope that the day will come soon when equally skilled and savvy researchers will show how to prevent and treat breast cancer with progesterone.

It’s important to note the term “high dose.” Lower doses of progesterone did not have the same effect, and even stimulated some types of tumor growth. Progesterone affects hundreds of kinds of cell receptors and biochemical interactions. It’s also important to note that the researchers’  “low dose” would be an ultra mega-dose when compared to using physiologic doses (e.g. 20 mg) of progesterone cream for hormone balance, or even using 100 mg of oral progesterone to help with insomnia.

The Emory team also recently published research showing that a combination of progesterone and vitamin D works better to protect the brain than progesterone alone.

The full articles for this research and the vitamin D research are available for free in a pdf file—click on the links below.

More Information

Atif F, Sayeed I, S, Ishrat T, Hua F, Wang J, Brat DJ, Stein DG, “Progesterone Inhibits the Growth of Human Neuroblastoma: In Vitro and In Vivo Evidence.” Mol Med. 2011 Jun 17. doi: 10.2119/molmed.2010.00255. [Epub ahead of print]

Cekic M, Stein DG, “Traumatic brain injury and aging: is a combination of progesterone and vitamin D hormone a simple solution to a complex problem?” Neurotherapeutics 2010 Jan;7(1):81-90.