Metformin protective against PCa in diabetic patients.

[pjoshea13]

New Canadian study (some US involvement) below [1].

"2,332 diabetic men were included, with a median follow-up time of 9.4 years (interquartile range 5.4-13.4 years).

"A total of 2,036 patients (87.3%) received metformin.

"Compared to non-metformin users, metformin use was associated with decreased CaP diagnosis rate" - 31% less

... "lower hazard of undergoing an additional" prostate biopsy - 36% less

... "and receiving ADT" - 28% less.

(association doesn't prove causality, etc, etc.)

Many men diagnosed with PCa are pre-diabetic. They may remain so forever (at least until ADT), but perhaps there would be a similar association if taken before diagnosis.

Or even after, when there is insulin resistance?

-Patrick

[1] pubmed.ncbi.nlm.nih.gov/329...

Oncol

. 2020 Sep 17;S1078-1439(20)30401-4. doi: 10.1016/j.urolonc.2020.08.032. Online ahead of print.

The suggested chemopreventive association of metformin with prostate cancer in diabetic patients

Hanan Goldberg 1 , Faizan K Mohsin 2 , Alejandro Berlin 3 , Thenappan Chandrasekar 4 , Christopher J D Wallis 5 , Zachary Klaassen 6 , Ardalan E Ahmad 7 , Refik Saskin 8 , Miran Kenk 9 , Olli Saarela 2 , Girish S Kulkarni 10 , Shabbir M H Alibhai 11 , Neil Fleshner 9

Affiliations collapse

Affiliations

1 Division of Urology, Department of Surgical Oncology, Princess Margaret Cancer Centre, University Health Network and the University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Department of Urology, SUNY Upstate Medical University, Syracuse, NY; Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada. Electronic address: [e-mail].

2 Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.

3 Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network; Department of Radiation Oncology, University of Toronto; and Techna Institute, University Health Network, Toronto, Ontario, Canada.

4 Department of Urology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia PA.

5 Division of Urology, Department of Surgical Oncology, Princess Margaret Cancer Centre, University Health Network and the University of Toronto, Toronto, Ontario, Canada; Department of Urology, Vanderbilt University Medical Center, Nashville, TN.

6 Division of Urology, Department of Surgery, Medical College of Georgia, Augusta University, Augusta, GA; Georgia Cancer Center, GA.

7 Division of Urology, Department of Surgical Oncology, Princess Margaret Cancer Centre, University Health Network and the University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada.

8 Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.

9 Division of Urology, Department of Surgical Oncology, Princess Margaret Cancer Centre, University Health Network and the University of Toronto, Toronto, Ontario, Canada.

10 Division of Urology, Department of Surgical Oncology, Princess Margaret Cancer Centre, University Health Network and the University of Toronto, Toronto, Ontario, Canada; Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.

11 Department of Medicine, University Health Network and University of Toronto, Toronto, Ontario, Canada.

PMID: 32951988 DOI: 10.1016/j.urolonc.2020.08.032

Abstract

Purpose: Metformin, an insulin sensitizer, is the most common first-line antidiabetic therapy. There is increasing evidence suggesting metformin can prevent the emergence of prostate cancer (CaP). We aimed to analyze the chemopreventive role of metformin, in conjunction with other putative chemopreventive medications (statins, proton-pump-inhibitors, alpha-blockers, 5-alpha-reductase inhibitors, diabetic medications) in a population-based cohort study.

Methods: Data were incorporated from the Institute for Clinical and Evaluative Sciences to identify all diabetic men aged 66 and above with prior history of a negative prostate biopsy (PB) between 1994 and 2016, who were not on any of the medications prior to study inclusion. Multivariable Cox regression models with time-dependent covariates were used to assess the association of metformin to CaP diagnosis, subsequent PB, and use of androgen deprivation therapy (ADT). All models were adjusted for age, rurality, comorbidity, and year of study inclusion.

Results: Overall, 2,332 diabetic men were included, with a median follow-up time of 9.4 years (interquartile range 5.4-13.4 years). A total of 2,036 patients (87.3%) received metformin. Compared to non-metformin users, metformin use was associated with decreased CaP diagnosis rate (HR 0.69, 95%CI 0.54-0.88, P = 0.003), lower hazard of undergoing an additional PB (HR 0.64, 95%CI 0.44-0.95, P = 0.03), and receiving ADT (HR 0.72, 95%CI 0.54-0.96, P = 0.003).

Conclusion: Men receiving metformin were less likely to have suspected or diagnosed CaP, and in those with CaP, the use of ADT was less common. Ongoing prospective randomized studies will determine if these findings correspond to the suggested associations of metformin in the emergence and/or progression of CaP.

Keywords: Androgen deprivation therapy; Diabetes; Metformin; Prostate biopsy; Prostate cancer.

Copyright © 2020 Elsevier Inc. All rights reserved.

[Hidden]

There is a lot of evidence showing that metformin is beneficial for PCa patients.

But a recent study shows that metformin blunts some of the positive changes from exercise.

onlinelibrary.wiley.com/doi...

Metformin in combination with rapamycin might be positive. I take a low dose of rapa once a week.

cancerpreventionresearch.aa...

I was taking 1500mg of metformin a day but I think I might cycle it or reduce it to off workout days. An SOC urologist at Mayo has studied it and begged me to go off of it completely. He said that we just don't know all that it might be doing to glucose pathways, mitochondria, etc.

[pjoshea13 in reply to Hidden]

Thanks!

I have often wondered about Rapamycin, since mTOR (mammalian target of rapamycin) is such an attractive target in PCa.

I suppose that a low dose (what is your weekly dose?) would have fewer potential side effects - do you tolerate it well?

Would you share the back-story on how you came to be treated with Rapamycin? Were you on a clinical trial?

en.wikipedia.org/wiki/Sirol...

en.wikipedia.org/wiki/Temsi...

Best, -Patrick

[Hidden in reply to pjoshea13]

I wasn't on a clinical trial. One of my doctors (he's a naturopath) told me about it. I think he's mostly interested in it for the longevity aspects. Looked promising for PCa though so I decided to take it. 2mg once a week. I haven't noticed any sides.

A higher dose impairs the immune system (used as an immunosuppressant during organ transplants) but the low dose apparently increases it's activity, particularly against cancer. And, as you mentioned, inhibits mTOR. I also saw some research indicating that it helps prevent muscle loss due to aging.

Thanks for the info. Cheers, Russ

[j-o-h-n]

Around...

Good Luck, Good Health and Good Humor.

j-o-h-n Monday 09/21/2020 6:16 PM DST

[Hidden]

I stumbled across this: sperlingprostatecenter.com/...

If someone does decide to take metformin, get an Rx for the med. If you decide to do the online overseas Rx thing realize and accept the risk.