bims-glucam Biomed News
on Glutamine cancer metabolism
Issue of 2022–01–30
seven papers selected by
Sreeparna Banerjee, Middle East Technical University



  1. NPJ Precis Oncol. 2022 Jan 27. 6(1): 8
      Immunometabolism within the tumor microenvironment is an appealing target for precision therapy approaches in lung cancer. Interestingly, obesity confers an improved response to immune checkpoint inhibition in non-small cell lung cancer (NSCLC), suggesting intriguing relationships between systemic metabolism and the immunometabolic environment in lung tumors. We hypothesized that visceral fat and 18F-Fluorodeoxyglucose uptake influenced the tumor immunometabolic environment and that these bidirectional relationships differ in NSCLC subtypes, lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). By integrating 18F-FDG PET/CT imaging, bulk and single-cell RNA-sequencing, and histology, we observed that LUSC had a greater dependence on glucose than LUAD. In LUAD tumors with high glucose uptake, glutaminase was downregulated, suggesting a tradeoff between glucose and glutamine metabolism, while in LUSC tumors with high glucose uptake, genes related to fatty acid and amino acid metabolism were also increased. We found that tumor-infiltrating T cells had the highest expression of glutaminase, ribosomal protein 37, and cystathionine gamma-lyase in NSCLC, highlighting the metabolic flexibility of this cell type. Further, we demonstrate that visceral adiposity, but not body mass index (BMI), was positively associated with tumor glucose uptake in LUAD and that patients with high BMI had favorable prognostic transcriptional profiles, while tumors of patients with high visceral fat had poor prognostic gene expression. We posit that metabolic adjunct therapy may be more successful in LUSC rather than LUAD due to LUAD's metabolic flexibility and that visceral adiposity, not BMI alone, should be considered when developing precision medicine approaches for the treatment of NSCLC.
    DOI:  https://doi.org/10.1038/s41698-021-00248-2
  2. Cell Biol Toxicol. 2022 Jan 27.
      Colorectal cancer (CRC) has high morbidity and mortality. Epithelial-mesenchymal transition (EMT) is associated with CRC progression and metastasis. Glutaminolysis is essential for malignancy of cancer cells. Here, we examined the effects of curcumol on CRC EMT. We observed that curcumol suppressed invasion and migration in human CRC cells associated with upregulation of epithelial markers E-cadherin and Zonula occludens 1 and downregulation of mesenchymal markers N-cadherin and Vimentin as well as EMT-related transcription factors Snail and Twist. Curcumol increased intracellular levels of glutamine but decreased intracellular levels of glutamate, α-ketoglutarate, ATP, glutathione, and tricarboxylic acid cycle metabolites, suggesting interruption of glutaminolysis. Next, curcumol repressed glutaminase 1 (Gls1) mRNA and protein expression, and overexpression of Gls1 promoted EMT and abolished curcumol effects on CRC cell EMT. Molecular examinations showed that curcumol stimulated protein degradation of hypoxia-inducible factor-1α (HIF-1α) and prevented its nuclear accumulation in CRC cells. HIF-1α agonist deferoxamine (DFO) promoted HIF-1α binding to Gls1 promoter and increased Gls1 expression but abolished curcumol's inhibitory effects on Gls1 expression. DFO also enhanced EMT and invasion and migration in CRC cells and eliminated curcumol effects. Furthermore, mouse CRC models were established with in vivo overexpression of HIF-1α and Gls1. Curcumol effectively inhibited CRC growth, metastasis, and EMT in mice, which was abrogated by overexpression of HIF-1α or Gls1. Altogether, stimulation of HIF-1α degradation was required for curcumol to disrupt EMT and repress invasion and migration in CRC cells through inhibiting Gls1-mediated glutaminolysis. Curcumol could be a promising candidate for intervention of CRC metastasis. • Curcumol inhibits EMT and blocks glutaminolysis in CRC cells. • Inhibition of Gls1 is required for curcumol blockade of glutaminolysis and EMT. • Curcumol induces HIF-1α degradation leading to inhibition of Gls1 and blockade of glutaminolysis and EMT. • Curcumol suppresses CRC growth and metastasis via inhibiting HIF-1α, glutaminolysis and EMT in mice.
    Keywords:  Colorectal cancer; Curcumol; EMT; Glutaminolysis; HIF-1α; Metastasis
    DOI:  https://doi.org/10.1007/s10565-021-09681-2
  3. J Cancer. 2022 ;13(2): 691-705
      Renal cell carcinoma (RCC), one of the most frequent cancers, is a "classical" malignancy characterized by metabolic reprogramming. Clear cell renal cell carcinoma (ccRCC) is its most common histopathological subtype. Long-stranded non-coding ribonucleic acids (LncRNAs) are regulatory RNA molecules with limited protein-coding capacity and evolutionary conservation. Recent studies have revealed that lncRNAs can broadly regulate the metabolic reprogramming of ccRCC and its malignant transformation. However, there are few studies on lncRNAs regulating the metabolism of ccRCC, and the specific mechanisms are unknown. Therefore, this paper summarizes the regulatory mechanisms of lncRNAs in the metabolism of ccRCC, especially in the pathways of glycolysis, mitochondrial function, glutamine and lipid metabolism, cellular mechanisms, interactions with other molecules, specific scientific and clinic implications and applications to provide a basis for early clinical diagnosis, prediction and treatment. We also discuss the clinical application and challenges of targeting lncRNAs in ccRCC metabolism.
    Keywords:  LncRNAs; metabolic reprogramming; renal clear cell carcinoma
    DOI:  https://doi.org/10.7150/jca.62683
  4. FASEB J. 2022 Feb;36(2): e22127
      Lung cancer has the highest incidence and mortality rates among all types of cancer worldwide, and 80%-85% of patients with lung cancer are diagnosed with non-small cell lung cancer (NSCLC), which has 5-year survival rate of only 5% at advanced stages. Development of new therapeutic agents and strategies is required to enhance the treatment efficiency in patients with NSCLC. Metabolic alterations and anticancer effects of plant hormones and their derivatives have not been investigated in NSCLC in vitro and in vivo. The present study investigated the cytotoxic effects of 11 plant hormones and their derivatives against NSCLC cell lines; ortho-topolin riboside (oTR) showed the highest cytotoxicity among all tested compounds against NSCLC cells. Alteration of metabolites and lipids was investigated using gas chromatography-mass spectrometry and nano electrospray ionization-mass spectrometry in oTR-treated NSCLC cells and a xenograft mouse model. oTR reduced amino acid and pyrimidine synthesis in NSCLC cells and xenograft tumors. Moreover, oTR reduced glycolytic function and decreased mitochondrial respiration function by inhibiting glutamine and fatty acid oxidation. Increased levels of phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine species suggested that oTR might act as a fatty acid oxidation inhibitor. In addition, the increased level of phosphatidylserine species implied that phosphatidylserine-mediated apoptosis occurred in oTR-treated NSCLC cells and xenograft tumor. The antiproliferative and apoptotic effects of oTR were mediated by the reduced p-ERK and p-AKT levels and increased cleaved Caspase-3 levels, respectively. This is the first study to investigate the metabolic alterations and anticancer activity of oTR in in vitro and in vivo models of NSCLC. Our results provide basis for the development of oTR-based therapeutic agent for patients with NSCLC.
    Keywords:  GC-MS; metabolic alteration; nanoESI-MS; non-small cell lung cancer; ortho-topolin riboside
    DOI:  https://doi.org/10.1096/fj.202101333R
  5. FEBS J. 2022 Jan 26.
      MRP1 (ABCC1) is a membrane transporter that confers multidrug resistance in cancer cells by exporting chemotherapeutic agents, often in a glutathione (GSH) dependent manner. This transport activity can be altered by compounds (modulators) that block drug transport while simultaneously stimulating GSH efflux by MRP1. In MRP1-expressing cells, modulator-stimulated GSH efflux can be sufficient to deplete GSH and increase sensitivity to chemotherapy, enhancing cancer cell death. Further development of clinically useful MRP1 modulators requires a better mechanistic understanding of modulator binding and its relationship to GSH binding and transport. Here, we explore the mechanism of two MRP1 small molecule modulators, 5681014 and 7914321, in relation to a bipartite substrate binding cavity of MRP1. Binding of these modulators to MRP1 was dependent on the presence of GSH but not its reducing capacity. Accordingly, the modulators poorly inhibited organic anion transport by K332L-mutant MRP1 where GSH binding and transport is limited. However, the inhibitory activity of the modulators was also diminished by mutations that limit E2 17βG but spare GSH-conjugate binding and transport (W553A, M1093A, W1246A), suggesting overlap between the E2 17βG and modulator binding sites. Immunoblots of limited trypsin digests of MRP1 suggest that binding of GSH, but not the modulators, induces a conformation change in MRP1. Together, these findings support the model in which GSH binding induces a conformation change that facilitates binding of MRP1 modulators, possibly in a proposed hydrophobic binding pocket of MRP1. This study may facilitate the structure-guided design of more potent and selective MRP1 modulators.
    Keywords:  MRP1/ABCC1; binding site; glutathione; modulator; structure
    DOI:  https://doi.org/10.1111/febs.16374
  6. Antioxid Redox Signal. 2022 Jan 24.
       SIGNIFICANCE: Mitochondria produce most of the cellular ATP through the process of oxidative phosphorylation. Energy metabolism in the mitochondria is associated with the production of reactive oxygen species (ROS). Excessive ROS production leads to oxidative stress and compromises cellular physiology. Energy metabolism in the mitochondria depends on nutrient flux and cellular metabolic needs, which are in turn connected with the feeding/fasting cycle. In animals, the feeding/fasting cycle is controlled by the circadian clock that generates 24-hour rhythms in behavior, metabolism and signaling. Recent Advances. Here, we discuss the role of the circadian clock and rhythms in mitochondria on ROS homeostasis. Circadian clock is involved in mitochondrial ROS production and detoxification through control of nutrient flux and oxidation, uncoupling, antioxidant defense and mitochondrial dynamics.
    CRITICAL ISSUES: Little is known on molecular mechanisms of circadian control of mitochondria functions. The circadian clock regulates the expression and activity of mitochondrial metabolic and antioxidant enzymes. The regulation involves a direct transcriptional control by CLOCK/BMAL1, NRF2 transcriptional network and sirtuin dependent posttranslational protein modifications. Future Perspectives. We hypothesize that the circadian clock orchestrates mitochondria physiology to synchronize it with the feeding/fasting cycle. Circadian coordination of mitochondrial function couples energy metabolism with diets and contributes to antioxidant defense to prevent metabolic diseases and delay aging.
    DOI:  https://doi.org/10.1089/ars.2021.0274
  7. Front Mol Biosci. 2021 ;8 791927
      The development of brain metastasis is a major cause of death in patients with breast cancer, characterized by rapid progression of the disease and poor prognosis, and lack of effective treatment has existed as an unresolved issue clinically. Extensive research has shown that a variety of metabolic changes associated with cellular metastasis exist in primary breast cancer or brain metastases, therefore to elucidate metabolic characteristics at each step of the metastasis cascade will provide important clues to the efficient treatment. In this review, we discuss the changes in metabolic patterns of breast cancer cells at every step of metastasis for exploring the potential therapeutic target based on metabolic reprogramming, and provide new insights on the design and development of drugs for breast cancer brain metastasis.
    Keywords:  brain metastasis; breast cancer; drug targets; metabolic reprogramming; metastatic cascade
    DOI:  https://doi.org/10.3389/fmolb.2021.791927