Project description:Most kidney cancers display metabolic dysfunction but how this relates to cancer progression in humans is unknown. We infused 13C-labeled nutrients during surgical tumour resection in over 80 patients with kidney cancer. Labeling from [U-13C]glucose varies across subtypes, indicating that the kidney environment alone cannot account for all metabolic reprogramming in these tumours. Compared to the adjacent kidney, clear cell renal cell carcinomas (ccRCC) display suppressed labelling of tricarboxylic acid (TCA) cycle intermediates in vivo and in organotypic cultures ex vivo, indicating that suppressed labeling is tissue intrinsic. Infusions of [1,2-13C]acetate and [U-13C]glutamine in patients, coupled with measurements of respiration in mitochondria isolated from kidneys and tumours, reveal electron transport chain (ETC) defects in ccRCC. However, ccRCC metastases unexpectedly have enhanced TCA cycle labeling compared to primary ccRCCs, indicating a divergent metabolic program during metastasis in patients. In mice, stimulating respiration or NADH recycling in kidney cancer cells is sufficient to promote metastasis, while inhibiting ETC complex I decreases metastasis. These findings indicate that metabolic properties and liabilities evolve during kidney cancer progression in humans, and that mitochondrial function is limiting for metastasis but not for growth at the original site.

2024-06-17 | GSE251905 | GEO

Developmental mitochondrial complex I activity determines lifespan

Project description:Aberrant mitochondrial function has been associated with an increasingly large number of human disease states. Observations from in vivo models where mitochondrial function is altered suggest that adaptations to mitochondrial dysfunction may underpin disease pathology. We hypothesized that the severity of these maladaptations could be shaped by the plasticity of the system when mitochondrial dysfunction manifests. To investigate this, we have used inducible fly models of mitochondrial complex I (CI) dysfunction to reduce mitochondrial function at two stages of the fly lifecycle, from early development and adult eclosion. Here, we show that in early life (developmental) mitochondrial dysfunction results in severe reductions in survival and stress resistance in adulthood, while flies where mitochondrial function is perturbed from adulthood, are long-lived and stress resistant despite having up to an 75% reduction in CI activity. After excluding developmental defects as a cause, we went on to molecularly characterize these two populations of mitochondrially compromised flies, short- and long-lived. We find that our short-lived flies have unique transcriptomic and metabolomic responses which overlap significantly in discreet models of CI dysfunction. Our data demonstrate that early mitochondrial dysfunction via CI depletion elicits an adaptive response which severely reduces survival, while CI depletion from adulthood is not sufficient to reduce survival and stress resistance.

2024-08-01 | GSE237015 | GEO

Mitochondrial micropeptide STMP1 promotes G1/S transition by enhancing mitochondrial complex IV activity.

Project description: Not available

| S-EPMC9372290 | biostudies-literature