NAD+ and Cancer
A post on Longecity.org four days ago entitled " NAD+ and Cancer" links to a recent Wistar Institute news release that cautions that boosting NAD+ levels in older animals leads to increased risk of cancer promotion by increasing the inflammatory secretions of senescent cell.
The original poster had a good followup that summarizes my view
I think some folks are missing the point of the thread. NAD+ does not cause cancer. Cancer uses any and all regenerative pathways in order to spread. Does that mean we should deplete our stem cells, inhibit dna repair, and promote cellular senescence? I would not be in the least surprised if they found that vigorous exercise slightly increases your risk of cancer, but lowers your risk of other types of diseases.
This reminds me of the "sugar causes cancer" meme. Researchers found out that cancer needs large quantities of sugar - no, not quite. The real story is that all of our cells utilize glucose (sugar basically) for energy, and tumors are fast growing and so need lots of energy. So no sugar doesn't cause cancer, but it is used by cancer to exist, just like the rest of your cells.
I didn't read the whole thread and won't pursue this for lack of time, but FWIW I strongly suspect similarities here, in that if you have cancer (tumors) then NAD might be as beneficial for them as it is for your regular cells.
Thanks DanMcL. for the response.
I don't know how to assess this alleged NAD+ risk, but one thought that's come to mind is related to the fact that this cancer promotion reputedly acts through senescent cells. One's senescent cell burden presumably rises exponentially throughout life. If I assume a senescent cell population doubling time of 8 years, then my senescent cell population would 10-fold about every 26.5 years, suggesting that the older I am, the greater the risk I'm at if I take NAD+ or its precursors.
Ironically, the older I are, the more I need NAD+ elevations.
My point is that among those of us who want to self-experiment with NAD+ augmentation, it's probably safer for them the lower their level of senescent cells. We Grandpas might be well advised to let spryer, younger folk test the waters(:-))
Another question I've got is: just how potent is this cancer promotion effect going to be? If I'm, say, 50, and I take, say, 500 mg. of an NAD+ enhancer daily for the next ten years, am I going to increase my chance of developing cancer by 1%? 10%? 100%?
A third question is: would the beneficial effects taking the NAD+ enhancer actually reduce my risk of getting cancer?
The original poster mentioned that the clearance of senescent cells via senolytics may be a way to reduce this cancer promotion risk. Can we get rid of enough senescent cells that this can become a solution?
I don't like this Wistar news at all!(:-)) Any answers?
The question is whether NAD+ causes cancer, or simply allows you live to an age where cancer would occur anyway.
My dentist told me about an antibiotic that is correlated with cancer. But in the study that identified the cancer, none of the control group were still alive when the first cancer occurred in the active group.
Age at cancer occurrence needs to be studied with regard to NAD+ usage.
An article was just published in the Scientific American that highlights the emerging evidence that NAD+ fuels the rapid growth of cancer cells.
For me, this reinforces the idea that we need to clear all senescent and pre-cancerous cells expressing the marker proteins p16 and p53 good things like feeding the rest of the cells with NAD+ and other boosters.
There is a paper where scientists found that interact NAD+ and senolytics could cause side-effects like cancer:
"A recent report links theseprocesses, such that decreased NAD+levels associated with aging may attenuate the SASP potentially reducingits pathological effect. Conversely, increasing NAD+levels by supplementation or genetic manipulation, whichmay benefit tissue homeostasis, also may worsen SASP and encourage tumorigenesis at least in mouse modelsof cancer. Taken together, these findings suggest a fundamental trade-off in treating aging-related diseases withdrugs or supplements that increase NAD+...
...So, accumulation of senescent cells may itself be aroot cause of decreased NAD+, which in turn could promote dysfunction. On the contrary, the lower NAD+levels may attenuate SASP, decreasing the pathological influence of senescence. The elimination of most senescent cells by senolysis before initiating NAD+therapies may be beneficial and increase safety, and in thebest-case scenario reduce the need for NAD+supplementation."
I also want start a self-experiment and I intuitively always think that first we should "clean the house" (senolytics) before try improve it (NAD+). This study confirms my expectations.