A examine of fasting and the ketogenic food regimen reveals a brand new vulnerability of pancreatic tumors to an present most cancers drug.
Scientists at UC San Francisco have found a solution to eliminate pancreatic most cancers in mice by placing them on a excessive fats, or ketogenic, food regimen and giving them most cancers remedy.
The most cancers remedy blocks fats metabolism, which is the most cancers’s solely supply of gas for so long as the mice stay on the ketogenic food regimen, and the tumors cease rising.
The group made the invention, which seems August 14 in Nature, whereas they have been making an attempt to determine how the physique manages to subsist on fats whereas fasting.
“Our findings led us straight to the biology of one of many deadliest cancers, pancreatic most cancers,” stated Davide Ruggero, PhD, Goldberg-Benioff Endowed Professor and American Most cancers Society Analysis Professor within the Departments of Urology and Mobile Molecular Pharmacology at UCSF and senior creator of the paper.
Ruggero’s group first uncovered how a protein generally known as eukaryotic translation initiation issue (eIF4E) adjustments the physique’s metabolism to change to fats consumption throughout fasting. The identical change additionally happens, due to eIF4E, when an animal is on a ketogenic food regimen.
They discovered {that a} new most cancers drug known as eFT508, presently in medical trials, blocks eIF4E and the ketogenic pathway, stopping the physique from metabolizing fats. When the scientists mixed the drug with a ketogenic food regimen in an animal mannequin of pancreatic most cancers, the most cancers cells starved.
Our findings open a degree of vulnerability that we will deal with with a medical inhibitor that we already know is protected in people. We now have agency proof of a method wherein food regimen could be used alongside pre-existing most cancers therapies to exactly eradicate a most cancers.”
Davide Ruggero, PhD, Goldberg-Benioff Endowed Professor and American Most cancers Society Analysis Professor within the Departments of Urology and Mobile Molecular Pharmacology at UCSF
Burning completely different fuels within the engine of the cell
People can survive for weeks with out meals, partly as a result of the physique burns saved fats.
Throughout fasting, the liver converts fat into ketone our bodies to make use of rather than glucose, the physique’s regular supply of power. Ruggero’s group discovered that eIF4E within the liver grew to become extra energetic, even because the liver paused its different metabolic exercise, suggesting that this issue was concerned in making ketone our bodies, a course of known as ketogenesis.
“Fasting has been a part of numerous cultural and spiritual practices for hundreds of years, typically believed to advertise well being,” stated Haojun Yang, PhD, post-doctoral researcher in Ruggero’s lab and first creator of the examine. “Our discovering that fasting remodels gene expression supplies a possible organic clarification for these advantages.”
By monitoring how completely different metabolic pathways modified throughout fasting, the scientists found that eIF4E was activated by the presence of free fatty acids, that are launched by fats cells early in fasting, so the physique has one thing to eat.
“The metabolite that the physique makes use of to make power can be getting used as a sign molecule throughout fasting,” Ruggero stated. “To a biochemist, seeing a metabolite act like a sign was the best factor.”
These identical adjustments within the liver – ketone physique manufacturing from burning fats, together with an increase in eIF4E exercise – additionally occurred when laboratory animals got a ketogenic food regimen consisting principally of fats.
That is when the lightbulb went off.
“As soon as we might see how the pathway works, we noticed the chance to intervene,” Ruggero stated.
The Achilles’ heel of pancreatic most cancers
The scientists first handled pancreatic most cancers with a most cancers drug known as eFT508 that disables eIF4E, intending to dam tumor development. But, the pancreatic tumors continued to develop, sustained by different sources of gas like glucose and carbohydrates.
Understanding that pancreatic most cancers can thrive on fats, and that eIF4E is extra energetic throughout fats burning, the scientists first positioned the animals on a ketogenic food regimen, forcing the tumors to eat fat alone, after which put them on the most cancers drug. On this context, the drug lower off the most cancers cells’ solely sustenance – and the tumors shrank.
Ruggero, together with Kevan Shokat, PhD, UCSF professor of mobile and molecular pharmacology, developed eFT508 within the 2010s, and it confirmed some promise in medical trials. However now, there’s a way more highly effective approach to make use of it.
“The sphere has struggled to firmly hyperlink food regimen with most cancers and most cancers remedies,” Ruggero stated. “However to actually join these items productively, you could know the mechanism.”
Totally different diet-drug mixtures will probably be wanted to deal with extra types of most cancers.
“We anticipate most cancers to produce other vulnerabilities,” Ruggero stated. “That is the muse for a brand new solution to deal with most cancers with food regimen and personalised therapies.”
Supply:
College of California – San Francisco
Journal reference:
Yang, H., et al. (2024). Remodelling of the translatome controls food regimen and its impression on tumorigenesis. Nature. doi.org/10.1038/s41586-024-07781-7.