Progesterone finally recognized as key to curing breast cancer

[haidut]

Ray has been writing for decades on the topic of using progesterone as treatment for cancer, and specifically breast cancer. After decades of denial and propaganda that progesterone may be a carcinogen it looks like mainstream medicine is finally warming up to the truth about progesterone and its role in breast cancer.
This is both sad and exciting. I wonder how many more lives will be lost before progesterone ends up on the list of official cancer treatments.
The study is behind a paywall, so if someone can get it for me I can post info on the in vivo doses of progesterone.

http://www.sciencealert.com/hormone-slo ... -new-study
http://www.healthcanal.com/cancers/brea ... ancer.html
http://www.nature.com/nature/journal/va ... 14583.html

"...But a new study has finally figured out why. ER+ cancer growth is driven by the hormone oestrogen acting on oestrogen receptor molecules inside the structure of the tumour. These oestrogen receptors bind to the tumour cells and activate their growth and proliferation, which is why ER+ patients are often treated with an oestrogen-blocking drug called tamoxifen. Not all patients respond to this drug in the same way, however, and it looks like the hormone progesterone could be a major factor in determining how successful this treatment is. A team of researchers from the UK and Australia tested this out by giving mice with breast cancer and cultured human breast cancer cells an extra dose of progesterone. This appeared to activate progesterone receptors in the breast tumours, which then directly affected the activity of the oestrogen receptors."

"..."It actually interacts with the oestrogen receptor to alter the way it works in a tumour cell," one of the team Wayne Tilley from the University of Adelaide in South Australia told Anna Salleh at ABC News. "If the progesterone receptor is not there, then the oestrogen receptor switches on all these genes that are associated with stimulating tumour growth and stimulating metastasis." This means if people have low levels of progesterone receptors, the oestrogen receptors are free to switch on aggressive genes that drive cancer growth and make hormone therapy less effective. "When the progesterone receptor is there, the oestrogen receptor sits in different parts of the DNA. You don't switch on those nasty genes but switch on those associated with a better outcome," says Tilley. When mice with breast cancer were given a treatment of tamoxifen combined with progesterone, the growth of their tumours slowed significantly more than in mice that were just giving the tamoxifen alone. "Tests showed that mice given progesterone and tamoxifen had breast tumours only half the size of those given the drug on its own," Ian Sample reports for The Guardian."

 

[Such_Saturation]

and California still claims it causes cancer.

 

[schultz]

 

[Philomath]

Fantastic! Thanks Schultz

 

[haidut]

OK, thanks.
Some more detailed info from the study:
"...Progesterone blocks ERa1 tumour growth: To explore the hypothesis that progesterone stimulation could have beneficial effects on ERa1 tumour growth in vivo, we established MCF-7-Luciferase xenografts in NOD/SCID/IL2Rg2/2 (NSG) mice and exposed the mice to control (that is, no hormone), slow release oestrogen pellets or slow release oestrogen plus standard high concentration progesterone pellets26. Ten tumours for each condition were implanted (two tumours per mouse and five mice per condition) and tumour formation was monitored using bioluminescent imaging. After 25 days, in the absence of any hormone, tumours did not grow, but stimulation with oestrogen alone resulted in tumour growth. Cotreatment with oestrogen plus progesterone resulted in a significant decrease in tumour volume, as compared to oestrogen alone, when measured by bioluminescence (Fig. 3a, b) (P50.0021) or tumour volume (P50.019) (Extended Data Fig. 6)."

So, in the absence of any hormones there was no tumor growth. So much for estrogen-negative breast cancer. Introducing estrogen restarted tumor growth and co-treatment with progesterone blocked the growth. The dose used in mice was 5.5mg/kg progesterone daily, and administered subcutaneously (as a sustained release pellet) for 25 days. This corresponds to a human dose of 0.4mg/kg daily, which means that 30mg - 40mg of progesterone daily should suffice. Since the progesterone was administered subcutaneously, a similar method in humans would be topical application. The absorption specifics of topically and subcutaneously applied hormones are pretty similar, which means that a 30mg - 40mg daily dose from a product like Progest-E should suffice to mimic the study design.
This study is very important for two reasons. One is that after decades of claiming that progesterone is not only useless as cancer treatment but is itself a carcinogen, medicine is finally changing the tune on progesterone. The second, and perhaps more important, is the confirmation of Ray's writings that synthetic progestins typically have no progesterone-like effects and in fact often act like an anti-progesterone. This would explain why the studies with synthetic progestins yielded null or negative results as a treatment for various cancers. So, only bioidentical progesterone is the way to go for breast cancer treatment. The synthetic progestins are often carcinogenic and should be avoided.
I am quite surprised this is not being covered more extensively by mainstream media. Two pillars of the dogma against progesterone are being challenged and nobody bats an eyelash...