Progesterone inhibits tumor growth – new study

progesterone-inhibits-tumor-growthA 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.

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11 Responses to "Progesterone inhibits tumor growth – new study"

  1. Carla Clawson   July 31, 2011 at 5:36 pm

    Excellent article as usual, Virginia. We appreciate your continued work in keeping us informed about the latest information on the benefits of progesterone.

  2. Elaine Hein   August 1, 2011 at 1:52 am

    Virgina, I do enjoy the emails and the very importaint information on your site.
    Could you please tell me where I can get information on traumatic brain injury and progesterone.
    I had an auto acciden 7 years ago and suffered traumatic brain injury.
    Thanking you in advance

  3. Virginia Hopkins   August 1, 2011 at 9:56 am

    Hi Elaine – the biggest benefits from progesterone for brain injury come in the first hours after the injury, but the brain is always making progesterone because it’s part of the myelin sheath that protects the nerves. Here’s a link to an article, Brain Research and Progesterone —

  4. Michelle Lingle   August 3, 2011 at 5:51 am

    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.

    Am I understanding this correctly to mean that the dose taken for hormone balance would be considered a “low dose” by the researchers standards?

  5. Glenda Cutchen   August 4, 2011 at 10:00 am

    I have been using bioidentical progesterone cream for several years to balance my hormones. If one uses high-dose progesterone for brain and breast cancer protection, how does that figure into “balanced” hormones. Two years ago I sent my saliva test kit to Dr Zava’s Lab and my progesterone was very high. I cut the amount that I was using in an effort to “balance” hormones. I was told that research shows that you no longer need to take a break from using progesterone, once a month. I have not subscribed to that idea. What do you recommend? If Vitamin D is used, what would be the correct amount? I really appreciate knowing that you are available and that good accurate information is available. So many news letters claim to be the “first” to introduce balanced bioidentical hormones. Linus Pauling peaked John Lee’s interest in this subject. I think most of these others were still in grade school at the time.

  6. kathy tegethoff   August 19, 2011 at 9:24 am

    Can using progesterone cream help my 17 year old daughter who has hirsutism and is more muscular than the average girl?

  7. Virginia Hopkins   August 21, 2011 at 6:11 pm

    Hi Kathy,
    With excessive hair growth the issue is usually with high testosterone, which in teen girls is usually caused by too much sugar and refined carbs in the diet, and not enough sunshine and exercise. For reasons we don’t understand fully, chronically high insulin (caused by too much sugar) stimulates the ovaries to make testosterone, and often causes polycystic ovary syndrome (PCOS). It might be wise to try a change in diet and exercise first, before adding hormones. That being said, in women who tend to get PMS, using a little bit of progesterone cream the 10 days before a period, stopping a few days before the period is due, can be a huge help. Here’s an article about how women can lower testosterone —

  8. Virginia Hopkins   August 21, 2011 at 6:15 pm

    Hi Glenda,
    Personally I don’t think using high dose progesterone would be preventive for brain and breast cancer protection. Balanced hormones are the best protection. High doses might be needed for treatment if a tumor already exists — we definitely need human research here!

  9. kathy tegethoff   August 26, 2011 at 7:42 pm

    The Dr wants to put my daughter on birth control pills for polycyctic ovary syndrome- I want to know if there is a natural way to treat PCOS other than BC pills! Please help!

  10. kathy tegethoff   September 16, 2011 at 7:04 am

    The dr wants to put my 17 year old daughter on the birth control pill to control her hirsutism!! Please, not that!! Help!

  11. Paula Osmundsen   September 19, 2011 at 3:09 pm

    Hello Virginia, I have followed you for years. Where can I get specific information on how and how much progesterone to use when you have metastatic breast cancer with boney mets? I have tried for years, to find a Dr. who understands how to use progesterone for this reason. I end up understanding Bio Identical hormones better than them…it’s very frustrating. I need some direction. Thank you