Alpha-Ketoglutarate Starves B-Cell Lymphoma by Depleting Key Amino Acids

**Why it matters:** Alpha-ketoglutarate is already consumed by health-conscious adults as a longevity supplement—studies in mice and nematodes show it extends lifespan and healthspan. This paper reveals an additional, potentially transformative property: selective suppression of B-cell lymphoma, one of the most common blood cancers. The convergence of longevity and anti-cancer biology in a single, apparently safe molecule is highly significant.

**What was studied:** Using human diffuse large B-cell lymphoma (DLBCL) cell lines, primary patient tumor samples, and transgenic Eμ-Myc mice that spontaneously develop B-cell lymphoma, the researchers tested cell-permeable αKG formulations (dimethyl-αKG and octyl-αKG) in vitro, ex vivo, and in vivo. Targeted mass spectrometry quantified 20 amino acids across 12 DLBCL lines. CRISPR-Cas9 knockouts (BCAT1, BCAT2, TET2, FTO, ALKBH5, HIF1α), ectopic gene expression (SLC1A3, constitutively active β-catenin, Raptor-Rheb15 lysosomal anchor), confocal microscopy for mTORC1 localization, and Seahorse metabolic flux assays were all deployed to dissect mechanism.

**Key results:** αKG caused a mean 73% growth inhibition across DLBCL lines, inducing apoptosis, suppressing Ki-67, and arresting cells in G0/G1—while normal splenic B cells and myeloid leukemia lines were largely spared. Metabolomics revealed rapid and sustained depletion of aspartate, alanine, leucine, isoleucine, and valine, with reciprocal rises in glutamate and glutamine, consistent with αKG driving transaminase reactions toward amino acid catabolism. Rescuing aspartate import (via ectopic SLC1A3 expression) or restoring leucine levels each partially blunted αKG's anti-lymphoma effect. Leucine depletion displaced mTORC1 from lysosomes, suppressing phosphorylation of its canonical targets p70S6K and 4EBP1. Genetically anchoring mTORC1 to the lysosome (Raptor-Rheb15 fusion) or deleting BCAT2—the enzyme catabolizing leucine—both rescued lymphoma cells from αKG. In vivo, IP αKG reduced tumor burden and significantly extended survival in adoptive-transfer lymphoma mice. Dietary αKG supplementation in Eμ-Myc mice delayed spontaneous lymphoma onset with no toxicity, and was associated with amino acid perturbation and impaired mitochondrial energy generation in splenic cells.

**Implications:** The data establish αKG as a multi-pronged metabolic disruptor in lymphoma: it depletes both non-essential (aspartate) and essential (leucine) amino acids through transaminase shunting, starving cancer cells of biosynthetic substrates and silencing mTORC1 signaling. Because normal B cells express low levels of relevant transporters and appear metabolically buffered, therapeutic selectivity may be achievable. The dietary supplementation finding is particularly compelling for longevity-focused audiences—it suggests that αKG's known healthspan benefits and its anti-lymphoma properties may be mechanistically linked through amino acid homeostasis.

**Caveats:** The study is largely preclinical; human clinical data are absent. The Eμ-Myc model, while well-validated, represents Myc-driven lymphoma and may not generalize to all DLBCL subtypes. Mechanistic dissection was performed primarily in cell lines, and the relative contribution of aspartate versus leucine depletion in vivo remains to be fully quantified.