Dr. D'Agostino: I can say that we know that dietary interventions...nutritional interventions can be powerful modulators of the immune system. And in some cases, a hypersensitive immune system will contribute to increased intestinal permeability. So intestinal hyper-reactivity is an immune response, and that intestinal hyper-reactivity will always lead to intestinal permeability, which can lead to impairing...you know, exacerbating an autoimmune condition. So I think dietary interventions are working through that way too and maybe suppressing some of the inflammatory mediators, IL-6, IL-1beta, TNF alpha, things like that. So, the ketogenic diet interesting can also augment the immune system in ways that makes it hyper-vigilant and being able to detect things like cancer cells, right? The ketogenic diet enhances the anti-cancer immunity of people that are following it.

Dr. Patrick: Oh, really?

Dr. D'Agostino: Yeah. So, a colleague of mine, Dr. Adrienne Scheck, did research with a glioblastoma cell line showing enhanced cancer-specific immune regulation, you know, with a dietary intervention. She was also using radiation. And also I think it needs to be appreciated that there's a lot of people who are against the standard of care, but I think the standard of care in the context of the ketogenic diet is a much more synergistic approach. So, when you give radiation, when you give chemotherapy, it's stimulating autophagy and it's stimulating tumor lysis syndrome. So you're actually like breaking down...you have bits of tumor that are entering circulation.

And it's not really talked about. I always think about it in this way, when you give someone chemo, it's killing cancer cells, and then you're stimulating autophagy and tumor lysis syndrome, and then that's stimulating the immune system. So, you know, I think chemotherapy, in general, is carcinogenic, it's bad, but it's also stimulating the immune system to then attack the cancer cell. In the context of a ketogenic diet, that a ketogenic diet, especially if it's calorie restricting, is stimulating cancer, it's putting metabolic stress on cancer cells and actually stimulating autophagy sort of in cancer cells, is stimulating cancer cell death. And it makes the tumor more sensitive to chemotherapy and radiation. So you have more tumor die off and you're also protecting the normal healthy cells. And it's augmenting the immune system in a way that's actually stimulating it more to attack the cancer.

So what I'm saying here is probably you can't go to any publication, but we just know from tumor biology that, you know, when you stimulate...when you kill cancer cells, you know, through any means, you can have this process called tumor lysis syndrome, which could kill the patient if you do it too abruptly, right? But that's why we're very, you know, adamant in advocating a more gradual approach, which would be like ketogenic diets, maybe metabolic drugs, and also hyperbaric oxygen therapy, or something that we studied.

But it needs to be acknowledged and recognized that chemotherapy and radiation also work by stimulating the immune system, and it works better in the context of a ketogenic diet, which makes the immune system more hypervigilant to be able to recognize and attack the cancer cells. So, there's a lot of research being done on that now. And, you know, I know the Moffitt Cancer Center, which is by USF, is very interested in immune-based therapies and using ketogenic diets to enhance like PD-L1 inhibitors like checkpoint inhibitors.

A paper just came out in a pretty high-impact journal, I forget the name of the journal. But it showed that PD-L1 inhibitors were greatly augmented in the context of the ketogenic diet. And even metabolic drugs like the PI3 kinase inhibitors are remarkably effective and promising, but they have a counter-regulatory effect at increasing insulin. So when we take these things, they can target tumor metabolism, but there's also an increase in insulin. And in the context of insulin suppression with a ketogenic diet, that can unmask and augment and greatly enhance PI3 kinase inhibitors. So Dr. Lou Cantley is really spearheading some of that work. And I've been in contact with a few of the patients in that that are doing like really well. And they're using a ketogenic diet to enhance, you know, the efficacy of that treatment.

Dr. Patrick: I know glioma. Gliomas are one type of cancer to seem to be responsible [crosstalk 02:06:05] evidence suggest, right?

Dr. D'Agostino: Yeah. That was my first interest in...because I started doing hyperbaric oxygen and I saw some...I saw, like, cancer cells exploding under hyperbaric oxygen. So this got me very interested in cancer, it was that. And I didn't know why they were exploding. And we had a dye that was looking at superoxide production in the cytosol and also in the mitochondria. So what I would see is that the mitochondria would light up really quick. We were doing optical sections with a laser scanning confocal microscope, and I can see that superoxide production was ramping up like super-high and super-fast when we hit it with oxygen. And then I would see the mitochondria disappear and then like the cells would rupture. So they're exploding. So we're giving high-pressure oxygen, and the tumor cells were taking that oxygen, and because the cancer cells have defective mitochondria, they put out proportionally more superoxide anion, which then can be converted to, you know, hydrogen peroxide and more reactive intermediates like hydroxyl radical. And then that damages membrane lipids and then you get rupturing of the cells. So I was like seeing this, and I was like, "This is very interesting." And what it was telling me is that...I didn't know why it was happening but later found out about the Warburg effect where you have an altered metabolism. Like some people say the Warburg effect is the cancer cell sort of changing metabolism for its own benefit to redirect nutrients and biomolecules to the biosynthetic anabolic production of...you know, for the expanding biomass of the tumor. So that's why.

And other people like Warburg said it was damaged respiration leads to compensatory fermentation, so the sugar cell consumes more glucose. But it was sort of looking at this effect which got me very interested in cancer in ways to target sort of cancer cells and then manipulate the substrates. So, that actually was the precursor to our cancer work with ketones because I was using hyperbaric oxygen, and then under different conditions, I started growing cancer cells and feeding them glucose and ketones. And then I would take away the glucose and keep the ketones, and the cancer cells would die. And then I would have glucose, and when I added ketones, it would decrease proliferation. So this is before I ever published anything, but it was like...it got the wheels turning, and I was like, "There's something that needs to be studied here."

So I had a few different med students replicate each other. So they could replicate it. So that gave me some confidence. And then a Ph.D. student came along, Dr. Angela Poff, who's hosting Metabolic Health Summit with... So she's now a research associate and does research among other things. And then she actually moved this to the animal model, which was ketogenic diet and hyperbaric oxygen and then later ketone supplementation. And that was a synergistic combination. So, the modified ketogenic diet we used was we took out the lard, and we put like a large percentage of the fat. Maybe 40% was MCTs and then we also used omega-3 fats with flaxseed oil.

At the time, I was very interested in MUFAs and PUFAs. We looked at what ketogenic diet researchers were using. I was like, "Well, let's make our own." So, we did like 20% instead of like 10%, you know, protein. We did like 20% or more protein, 20% to 25%. And then we replaced the fats with essentially MCT, flaxseed oil, and then we put some fiber in there too. And then that became the diet we actually use for the Alzheimer's research, and then we use this diet for our cancer research. And our effects were pretty robust, and I often think, you know, was it because we were using, you know, a diet high in like, you know, omega-3 oils and we just... We also had higher protein, which I think was a little bit beneficial. But we had high ketones. So we did different diets and this diet especially with the MCTs gave us higher ketones and seemed to work really well.

Dr. Patrick: Wow, super-interesting. What about, you know, the different...? There's different types of cancer, and I know we were discussing this a little bit earlier, you know, the potential for some types of cancer at least in rodent studies to, you know, maybe metabolize some ketones and use them in a positive way to benefit the cancer cell. Is that something...?

Dr. D'Agostino: There's no doubt they do. So there's a little bit of... Cancers are more heterogeneous than we'd sort of like to believe. I think the field at large believes that, and that's why we have all these different cancer therapies. There are some cancers that are very responsive to the ketogenic diet. But when I think of the ketogenic diet as a cancer therapy, I don't think of it as...I don't think of the hyperketonemia treating the cancer cells. The therapeutic efficacy of the ketogenic diet is through insulin suppression and suppressing the insulin pathway, limiting glucose availability, and also to some extent elevating ketones. We know this because, if we put exogenous ketones into a standard diet, we can extend the life of animals that have metastatic cancer. So we've published that in the "International Journal of Cancer." But what was happening was when you put the ketones in the standard diet food, they probably eat a little bit less, and it's also lowering blood glucose and changing metabolic physiology. So it may not be... And then the reviewers rightly asked, they said, "Well, go do a calorie restriction group." So we took a standard diet and calorie-restricted like 25%, and we saw an increase in survival, but it was nowhere near the increase in survival from adding the ketones to the standard diet. So we did that control.

So to get back to your question, yeah, I think, you know, brain tumors, aggressive, you know, solid tumors, endometrial cancers, maybe certain GI cancers, maybe lung cancer, you know, are responsive. The cancers that are associated with metabolic derangement are probably responsive, also cancers that are more aggressive or more glycolytic. So they're more likely to respond. And brain cancers are a good cancer to study because you get seizures with brain cancers and because the tools, the treatments are so limited. Like glioblastoma we just know that standard of care does not work. So you want to use something. A dietary approach can then potentially make the existing drugs work or augment the many different factors that could make the brain cancer more responsive to the tumor.

But there are different mutations. There's one for melanoma, BRAF V600E mutation, I believe, which changes the tumor metabolism in a way that can actually maybe cause acetoacetate to be used as fuel. Some cancers may respond to ketones in ways that are different than other cancer cells like the brain tumor cells that we've studied in the lab. So, in particular, there's a melanoma cell line at least that has BRAF V600E mutation, I believe. And those cancer cells have been shown to use acetoacetate as potentially an energy source but also for biosynthetic reactions. And I suspect there's a variety of different cancer cells that can use ketones, not only as a biosynthetic molecule, but maybe even for energy too. But I think largely, cancer cells that are more aggressive have reverted back to a glycolytic phenotype where they're primarily relying on fermentable fuels, and that includes glucose and glutamine are the two fuels.

And cancer cells that are more glycolytic and very sort of damaged in their respiration due to the hypoxia of expanding tumor mass. So, as a tumor grows, it outstrips its ability to supply blood flow and oxygen to the tumor. So it becomes hypoxic, and that further damages the mitochondria. So it causes the tumor to be more glycolytic and less of the oxidative phosphorylation pathway. So, literally, this would mean that tumor cells...especially the core of expanding tumor biomass would not be able to use ketones as an energy source because it's a mitochondrial energy, you know, event. So in that way, we think that ketones are not, you know, an ideal fuel for tumors, and in our model systems, you know, it's very clear that they cannot run...in the absence of glucose, tumor cells die, whereas even in the presence of consistent glucose when we add ketones, there seems to be a decrease in proliferation. And we think that could be due to a ketone-induced decrease in hexokinase, which is a glycolytic enzyme. So there's a lot of potential I think for using ketogenic diets as, you know, an adjuvant therapy and then maybe some potential as using exogenous ketones as a means to influence the tumor microenvironment and also to influence essentially the metabolism of the tumor as a whole.

Dr. Patrick: And also as you mentioned earlier with Dr. Eric, Verdin, and John Ramsey's co-published studies, there was a reduction...I mean, there's a possible preventative, you know, mechanism as well with at least...according to animal research, there being a reduction in spontaneous tumors in these rodents seems promising to study, you know, as well if there's any way we can reduce cancer incidents. You know, it's always easier to not get cancer than to try to treat it.

Dr. D'Agostino: Exactly. Yeah.

Dr. Patrick: So, you know, that's also really a sort of interesting and promising field that...

Dr. D'Agostino: I mean, those results were impressive, so suppressing tumor growth through probably IGF-1 and mTOR and just suppressing...keeping inflammation low, and many other, you know, biomarkers I think it's optimizing to do that. But if we take these ketogenic diets and optimize it with specific phytonutrients and we add some fiber in and we add...then it becomes difficult to figure out what's doing what. But I do feel that there's some synergy in optimizing a ketogenic diet with plant, you know, fiber and phytonutrients that we know have anti-carcinogenic effects like curcumin and turmeric and EGCG, and, you know, there's groups at the Cancer Institute that spend their whole life studying just a handful of these phytonutrients, and they show that it has remarkable chemo-prevention effects. So we should be incorporating these into the ketogenic diet [crosstalk 02:17:43]