Background: Akt signalling regulates glycolysis and drives the Warburg effect in cancer, thus decreased glucose utilisation is a pharmacodynamic marker of Akt inhibition. However, cancer cells can utilise alternative nutrients to glucose for energy such as lactate, which is often elevated in tumours together with increased acidity. We therefore hypothesised that lactic acidosis may confer resistance to Akt inhibition.
Methods: The effect of the pan-Akt inhibitor uprosertib (GSK2141795), on HCT116 and LS174T colon cancer cells was evaluated in the presence and absence of lactic acid in vitro. Expression of downstream Akt signalling proteins was determined using a phosphokinase array and immunoblotting. Metabolism was assessed using H nuclear magnetic resonance spectroscopy, stable isotope labelling and gas chromatography-mass spectrometry.
Results: Lactic acid-induced resistance to uprosertib was characterised by increased cell survival and reduced apoptosis. Uprosertib treatment reduced Akt signalling and glucose uptake irrespective of lactic acid supplementation. However, incorporation of lactate carbon and enhanced respiration was maintained in the presence of uprosertib and lactic acid. Inhibiting lactate transport or oxidative phosphorylation was sufficient to potentiate apoptosis in the presence of uprosertib.
Conclusions: Lactic acidosis confers resistance to uprosertib, which can be reversed by inhibiting lactate transport or oxidative metabolism.
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http://dx.doi.org/10.1038/s41416-020-0777-y | DOI Listing |
Neuromuscul Disord
December 2024
University of Florida College of Medicine - Jacksonville, Jacksonville, FL, USA.
Sengers Syndrome (SS) is a rare autosomal recessive mitochondrial disorder caused by mutations in the acylglycerol kinase (AGK) gene on chromosome 7, also known as cardiomyopathic mitochondrial DNA depletion syndrome (MTDPS10). This disorder disrupts mitochondrial DNA function and energy metabolism, presenting with symptoms such as congenital cataracts, hypertrophic cardiomyopathy, skeletal myopathy, exercise intolerance, and lactic acidosis. Previous research has shown SS affects oxidative phosphorylation and mitochondrial respiration, implicating the TIM22 complex and carrier import.
View Article and Find Full Text PDFClin Neurol Neurosurg
January 2025
Department of Neurology, University of Health Sciences, Sancaktepe Şehit Prof. Dr. İlhan Varank Training and Research Hospital, Istanbul, Turkey. Electronic address:
Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is one of the most common mitochondrial disorders, typically presenting with symptoms before the age of 40. Epileptic seizures are a common manifestation, with both focal and generalized seizures being observed. EEG findings can be variable, with the most common patterns being slow background activity followed by epileptiform discharges.
View Article and Find Full Text PDFObjective: To analyze the clinical effectiveness of Entecavir (ETV) and Tenofovir Disoproxil Fumarate (TDF) Tablets for the treatment of chronic hepatitis B (CHB).
Methods: Clinical data from 100 CHB patients admitted to our hospital from April 2022 to April 2024 were retrospectively reviewed. Of these, 45 cases in the control group received ETV, and 55 cases in the research group received TDF tablets.
Cureus
December 2024
Division of Pulmonary Critical Care Medicine, Charleston Area Medical Center, Charleston, USA.
Abdominal pain is a common presenting symptom among patients visiting the hospital. A wide range of differential diagnoses are associated with this presentation, some of which are more uncommon than others, and require a higher degree of clinical suspicion and radiological excellence to diagnose. Although clinicians rely on physical assessment, examining a patient who is agitated and non-cooperative sometimes limits the physical exam findings, making these diagnoses even more challenging.
View Article and Find Full Text PDFMol Genet Genomic Med
January 2025
Diagnostics and Therapeutics of Intractable Diseases, Intractable Disease Research Center, Graduate School of Medicine, Juntendo University, Tokyo, Japan.
Background: Sengers syndrome is an autosomal recessive mitochondrial DNA depletion syndrome characterized by hypertrophic cardiomyopathy, congenital cataracts, skeletal myopathy, exercise intolerance, and lactic acidosis. Dysfunction of acylglycerol kinase (AGK) is responsible for the disease, and several AGK gene variants have been reported.
Methods: We employed a comprehensive genomic analysis approach, including whole-genome sequencing and RNA sequencing, combined with various bioinformatics tools.
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