Marcus Goncalves Profile picture
MD/PhD Endocrinologist and scientist. Cancer metabolism, cachexia, insulin signaling, diabetes, and obesity. Metabolic Consulting LLC. Former NYJ/NYY/NYCFC fan.

Aug 18, 2021, 26 tweets

A couple years ago, we showed that dietary fructose enhances intestinal tumor growth. Today, I’m excited to expand these results to the normal intestine and discuss the implications for obesity and cancer. @Nature nature.com/articles/s4158…

Congratulations to @SamwiseT whose tenacity, creativity, and dedication pushed us to the next level. If you’re running a MRT/PTSP be on the lookout for his application next year! @TriIMDPhD @WeillCornellGS

So many gems in here, but let’s start with the big guns. Dietary fructose improves intestinal cell survival and elongates villi. @SamwiseT wrote a semi automated program to quantify the length. Freely available here: github.com/sam-taylor/Vil…

We confirmed that this lengthening effect was present in male and female mice of different genetic backgrounds. It takes at least 10 days in a mouse (about 2 cycles of villous turnover) and it’s reversible if the fructose is removed.

Longer villi=more surface area. Did fructose also improve nutrient absorption? Yes, and it wasn’t subtle.

“Western diets” (high fat, high fructose) lead to more adiposity than high fat diets without fructose. We reproduced these findings and showed that the villi in Western diet fed mice were longer and extracted more calories from their stool. No change in food intake or EE.

These data make me wonder about the old calories in, calories out model of obesity. #CICO @KevinH_PhD is there any evidence for a modifiable absorption term in your models?

Back to the villi. How exactly are they getting longer? Are the stem cells in the crypt proliferating more? We checked that using dual BrdU/EdU tracing and the migration rate was unchanged.

We also added fructose to the media of mouse intestinal organoids (@dow_lab @alynakatti) and about a dozen human CRC lines. Still no change in proliferation. This series of “negative” data resulted in @RogerLiang9 recent paper cancerandmetabolism.biomedcentral.com/articles/10.11…

I didn’t know this beforehand but the villous tip is one of the most hypoxic places in the body. Sam gave pimodinazole in vivo to document hypoxia. Then he showed that it overlapped with TUNEL and CC3 staining.

With that in mind, we started to culture the cells in hypoxia and Woop! There is was. #BigPhenotype Fructose promotes cell survival in hypoxia.

A side note. The @cantleylab hypoxia chamber has been broken for generations. Sorry, @EvanNoch, it’s true. @samwiseT fixed it with a soldering iron and some random parts from Amazon. Now it’s the #GoncalvesLab hypoxia chamber

With an in vitro model in hand, we spent countless hours on #KyuRhee’s machines and gallons of his solvents (thanks ). Then... one night after reviewing metabolomics data, @mvh_lab @AnastasiouLab and @ChristofkLab appeared in a dream and asked me why F1P looks so much like FBP?

The data showed a block at the PEP to Pyr transition, and we found F1P is a great PKM2 inhibitor. It likely binds in the FBP binding pocket and interacts w/serine 519 to prevent tetramer formation. We tested recombinant enzymes, cell/tissue lysates, and primary human tumor tissue

The last piece of the puzzle came from a peer reviewer who asked about PKM2’s nuclear activity. We were reminded of Greg Semenza’s work showing a link between PKM2 and HIF1a activity. doi.org/10.1016/j.cell…

So we tested if fructose exposure can transactivate a HIF1a reporter in a PK specific manner, and it does!

Move over mTOR, is PKM2 the cell's major nutrient sensor?

Armed with this new Fructose-F1P-PKM2-HIF1a pathway, we went back to the mice. Deletion of KHK or activation of PKM2 both prevented fructose induced villus length.

Also, a small molecule activator of PK prevents and reverses villous hypertrophy

And bringing it full circle to our work from 2019 science.sciencemag.org/content/363/64…, PK activation prevents and reverses the HFCS-induced tumor growth.

How can we translate our work to humans? First, we’re working with Alessio Pigazzi of @WCMSurgery and @nyphospital to confirm primary human CRC tumors take up and metabolize fructose. IRB is almost approved.

How can we translate our work to humans? I would love to find a clinical collaborator to help me confirm the effects of fructose on villous length. #GITwitter, message me!

How can we translate our work to humans? There are clinical grade KHK inhibitors and PK activators in development and we would love to get our hands on some of these. @pfizer @agiospharma

This has been a really fun project. I love being able to work with all stars spanning the biomedical research spectrum from protein biochemists to clinical researchers. Thanks @dow_lab, @cantleylab, @mdmanishshah, @neilvasan, @SRamsamooj7, #KyuRhee, #RobertSebra, #AJDannenberg

Finally, I want to thanks all that have supported me, the lab, and this project @WeillCornell @NCICRCHD @AACR @TheMarkFdn @lcrf_org @NCI @NIH_LRP @NIGMS @SU2C

also, we're always looking for good people goncalveslab.com/postdoc

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