bims-stacyt 2019-02-03 papers

FASEB J. 2019 Jan 30. fj201802226R

Tumoral microvesicle-activated glycometabolic reprogramming in fibroblasts promotes the progression of oral squamous cell carcinoma.

Erhui Jiang, Zhi Xu, Meng Wang, Tinglin Yan, Chunming Huang, Xiaocheng Zhou, Qing Liu, Lin Wang, Yang Chen, Hui Wang, Ke Liu, Zhe Shao, Zhenjun Shang.

Metabolic reprogramming is a hallmark of cancer. Stromal cells could function as providers of energy metabolites for tumor cells by undergoing the "reverse Warburg effect," but the mechanism has not been fully elucidated. The interaction between the tumoral microvesicles (TMVs) and stroma in the tumor microenvironment plays a critical role in facilitating cancer progression. In this study, we demonstrated a novel mechanism for the TMV-mediated glycometabolic reprogramming of stromal cells. After being incubated with TMVs, normal human gingival fibroblasts exhibited a phenotype switch to cancer-associated fibroblasts and underwent a degradation of caveolin 1 (CAV1) through the ERK1/2-activation pathway. CAV1 degradation further induced the metabolic switch to aerobic glycolysis in the fibroblasts. The microvesicle-activated fibroblasts absorbed more glucose and produced more lactate. The migration and invasion of oral squamous cell carcinoma (OSCC) were promoted after being cocultured with the activated fibroblasts. Fibroblast-cancer cell glycometabolic coupling ring mediated by monocarboxylate transporter (MCT) 4 and MCT1 was then proved in the tumor microenvironment. Results indicated a mechanism for tumor progression by the crosstalk between tumor cells and stromal cells through the reverse Warburg effect via TMVs, thereby identifying potential targets for OSCC prevention and treatment.-Jiang, E., Xu, Z., Wang, M., Yan, T., Huang, C., Zhou, X., Liu, Q., Wang, L., Chen, Y., Wang, H., Liu, K., Shao, Z., Shang, Z. Tumoral microvesicle-activated glycometabolic reprogramming in fibroblasts promotes the progression of oral squamous cell carcinoma.

Keywords: OSCC; metabolism; reverse Warburg effect; tumor microenvironment; tumor-stroma interaction

DOI: https://doi.org/10.1096/fj.201802226R

J Biol Chem. 2019 Jan 29. pii: jbc.RA118.005892. [Epub ahead of print]

IL-18 upregulates amino acid transporters and facilitates amino acid-induced mTORC1 activation in natural killer cells.

Saeedah Musaed Almutairi, Alaa Kassim Ali, William He, Doo-Seok Yang, Peyman Ghorbani, Lisheng Wang, Morgan D Fullerton, Seung-Hwan Lee.

Upon inflammation, NK cells undergo metabolic changes to support their high energy demand for effector function and proliferation. The metabolic changes are usually accompanied by an increase in the expression of nutrient transporters leading to increased nutrient uptake. Among various cytokines inducing NK cell proliferation, the mechanisms underlying the effect of IL-18 in promoting NK cell proliferation is not completely understood. Here, we demonstrate that IL-18 is a potent cytokine that can enhance the expression of the nutrient transporter CD98/LAT1 for amino acids independently of mTORC1 pathway and thereby induce a dramatic metabolic change, associated with an increased proliferation of NK cells. Notably, treatment of IL-18-stimulated NK cells with leucine activates the metabolic sensor mTORC1, indicating that the high expression of amino acid transporters induces amino acid-driven mTORC1 activation. Inhibition of the amino acid transporter CD98/LAT1 abrogated the leucine-driven mTORC1 activation and reduced NK cell effector function. Taken together, our study identified a novel role of IL-18 in upregulating nutrient transporters on NK cells and thereby inducing metabolic changes including the mTORC1 activation by amino acids.

Keywords: Interleukin-18 (IL-18); amino acid; cell metabolism; cell proliferation; mammalian target of rapamycin (mTOR); natural killer cells (NK cells); nutrient uptake

DOI: https://doi.org/10.1074/jbc.RA118.005892

Nat Rev Immunol. 2019 Jan 31.

Itaconate: the poster child of metabolic reprogramming in macrophage function.

Luke A J O'Neill, Maxim N Artyomov.

Itaconate is one of the best examples of the consequences of metabolic reprogramming during immunity. It is made by diverting aconitate away from the tricarboxylic acid cycle during inflammatory macrophage activation. The main reason macrophages exhibit this response currently appears to be for an anti-inflammatory effect, with itaconate connecting cell metabolism, oxidative and electrophilic stress responses and immune responses. A role for itaconate in the regulation of type I interferons during viral infection has also been described, as well as in M2 macrophage function under defined circumstances. Finally, macrophage-specific itaconate production has also been shown to have a pro-tumour effect. All of these studies point towards itaconate being a critical immunometabolite that could have far-reaching consequences for immunity, host defence and tumorigenesis.

DOI: https://doi.org/10.1038/s41577-019-0128-5

Cancers (Basel). 2019 Jan 29. pii: E154. [Epub ahead of print]11(2):

Extracellular Vesicles as Transmitters of Hypoxia Tolerance in Solid Cancers.

Marijke I Zonneveld, Tom G H Keulers, Kasper M A Rouschop.

Tumour hypoxia is a common feature of solid tumours that contributes to poor prognosis after treatment. This is mainly due to increased resistance of hypoxic cells to radio- and chemotherapy and the association of hypoxic cells with increased metastasis development. It is therefore not surprising that an increased hypoxic tumour fraction is associated with poor patient survival. The extent of hypoxia within a tumour is influenced by the tolerance of individual tumor cells to hypoxia, a feature that differs considerably between tumors. High numbers of hypoxic cells may, therefore, be a direct consequence of enhanced cellular capability inactivation of hypoxia tolerance mechanisms. These include HIF-1α signaling, the unfolded protein response (UPR) and autophagy to prevent hypoxia-induced cell death. Recent evidence shows hypoxia tolerance can be modulated by distant cells that have experienced episodes of hypoxia and is mediated by the systemic release of factors, such as extracellular vesicles (EV). In this review, the evidence for transfer of a hypoxia tolerance phenotype between tumour cells via EV is discussed. In particular, proteins, mRNA and microRNA enriched in EV, derived from hypoxic cells, that impact HIF-1α-, UPR-, angiogenesis- and autophagy signalling cascades are listed.

Keywords: HIF-1α; UPR; autophagy; exosomes; phenocopying; preconditioning

DOI: https://doi.org/10.3390/cancers11020154