Manas Kohli

The lack of curative therapies for acute myeloid leukaemia (AML) remains an ongoing challenge despite recent advances in the understanding of the molecular basis of the disease. Here we identify the WNK1-OXSR1/STK39 pathway as a previously uncharacterised dependency in AML. We show that genetic depletion and pharmacological inhibition of WNK1 or its downstream phosphorylation targets OXSR1 and STK39 strongly reduce cell proliferation and induce apoptosis in leukaemia cells in vitro and in vivo. Furthermore, we show that the WNK1-OXSR1/STK39 pathway controls mTORC1 signalling via regulating amino acid uptake through a mechanism involving the phosphorylation of amino acid transporters, such as SLC38A2. Our findings underscore an important role of the WNK1-OXSR1/STK39 pathway in regulating amino acid uptake and driving AML progression.

Metabolic reprogramming is a hallmark of cancer, with cancer cells acquiring many unique metabolic traits to support malignant growth, and extensive intra- and inter-tumour metabolic heterogeneity. Understanding these metabolic characteristics presents opportunities in precision medicine for both diagnosis and therapy. However, despite its potential, metabolic phenotyping has lagged behind genetic, transcriptomic, and immunohistochemical profiling in clinical applications. This is partly due to the lack of a single experimental technique capable of profiling the entire metabolome, necessitating the use of multiple technologies and approaches to capture the full range of cancer metabolic plasticity. This review examines the repertoire of tools available for profiling cancer metabolism, demonstrating their applications in preclinical and clinical settings. It also presents case studies illustrating how metabolomic profiling has been integrated with other omics technologies to gain insights into tumour biology and guide treatment strategies. This information aims to assist researchers in selecting the most effective tools for their studies and highlights the importance of combining different metabolic profiling techniques to comprehensively understand tumour metabolism.

Voltage-gated sodium channel α-subunits (NaV1.1–1.9) initiate and propagate action potentials in neurons and myocytes. The NaV β-subunits (β1–4) have been shown to modulate α-subunit properties. Homo-oligomerization of β-subunits on neighboring or opposing plasma membranes has been suggested to facilitate cis or trans interactions, respectively. The interactions between several NaV channel isoforms and β-subunits have been determined using cryogenic electron microscopy (cryo-EM). Interestingly, the NaV cryo-EM structures reveal the presence of N-linked glycosylation sites. However, only the first glycan moieties are typically resolved at each site due to the flexibility of mature glycan trees. Thus, existing cryo-EM structures may risk de-emphasizing the structural implications of glycans on the NaV channels. Herein, molecular modeling and all-atom molecular dynamics simulations were applied to investigate the conformational landscape of N-linked glycans on NaV channel surfaces. The simulations revealed that negatively charged sialic acid residues of two glycan sites may interact with voltage-sensing domains. Notably, two NaV1.5 isoform-specific glycans extensively cover the α-subunit region that, in other NaV channel α-subunit isoforms, corresponds to the binding site for the β1- (and likely β3-) subunit immunoglobulin (Ig) domain. NaV1.8 contains a unique N-linked glycosylation site that likely prevents its interaction with the β2 and β4-subunit Ig-domain. These isoform-specific glycans may have evolved to facilitate specific functional interactions, for example, by redirecting β-subunit Ig-domains outward to permit cis or trans supraclustering within specialized cellular compartments such as the cardiomyocyte perinexal space. Further experimental work is necessary to validate these predictions.

Metabolic reprogramming is a hallmark of cancer, with cancer cells acquiring many unique met-abolic traits to support malignant growth, and extensive intra- and inter-tumour metabolic het-erogeneity. Understanding these metabolic characteristics presents opportunities in precision medicine for both diagnosis and therapy. However, despite its potential, metabolic phenotyping has lagged behind genetic, transcriptomic and immunohistochemical profiling in clinical appli-cations. This is partly due to the lack of a single experimental technique capable of profiling the entire metabolome, necessitating the use of multiple technologies and approaches to capture the full range of cancer metabolic plasticity. This review examines the repertoire of tools available for profiling cancer metabolism, demonstrating their applications in preclinical and clinical settings. It also presents case studies illustrating how metabolomic profiling has been integrated with oth-er omics technologies to gain insights into tumour biology and guide treatment strategies. This information aims to assist researchers in selecting the most effective tools for their studies and highlights the importance of combining different metabolic profiling techniques to comprehen-sively understand tumour metabolism.

Highlights Three N-linked glycosylation sites conserved among all Nav channels Glycan modelling and molecular dynamics simulations highlight 3D landscape Unique Nav1.5 N-linked glycans may prevent binding to Ig-domains of β1 and β3 Unique Nav1.8 N-linked glycan may prevent binding to Ig-domains of β2 and β4 N-linked glycans likely contribute to supra-molecular clustering of Nav channels Voltage-gated sodium channel α-subunits (Nav1.1-1.9) initiate and propagate action potentials in neurons and myocytes. The Nav β-subunits (β1-4) have been shown to modulate α-subunit properties. Homo-oligomerization of β-subunits on neighboring or opposing plasma membranes has been suggested to facilitate cis or trans interactions, respectively. The interactions between several Nav channel isoforms and β-subunits have been determined using cryogenic electron microscopy (cryo-EM). Interestingly, the Nav cryo-EM structures reveal the presence of N-linked glycosylation sites. However, only the first glycan moieties are typically resolved at each site due to the flexibility of mature glycan trees. Thus, existing cryo-EM structures may risk de-emphasizing the structural implications of glycans on the Nav channels. Herein, molecular modelling and all-atom molecular dynamics simulations were applied to investigate the conformational landscape of N-linked glycans on Nav channel surfaces. The simulations revealed that negatively-charged sialic acid residues of two glycan sites may interact with voltage-sensing domains. Notably, two Nav1.5 isoform-specific glycans extensively cover the α-subunit region that, in other Nav channel α-subunit isoforms, corresponds to the binding site for the β1-(and likely β3-) subunit immunoglobulin (Ig) domain. Nav1.8 contains a unique N-linked glycosylation site that likely prevents its interaction with the β2 and β4-subunit Ig domain. These isoform-specific glycans may have evolved to facilitate specific functional interactions, for example by redirecting β-subunit Ig-domains outwards to permit cis or trans supra-clustering within specialized cellular compartments such as the cardiomyocyte perinexal space. Further experimental work is necessary to validate these predictions.