Acute myeloid leukemia (AML) is a clonal disorder arising from hematopoietic myeloid progenitors. Aberrantly activated tyrosine kinases (TK) are involved in leukemogenesis and are associated with poor treatment outcome. Kinase inhibitor (KI) treatment has shown promise in improving patient outcome in AML. However, inhibitor selection for patients is suboptimal.

In a preclinical effort to address KI selection, we analyzed a panel of 16 AML cell lines using phosphotyrosine (pY) enrichment-based, label-free phosphoproteomics. The Integrative Inferred Kinase Activity (INKA) algorithm was used to identify hyperphosphorylated, active kinases as candidates for KI treatment, and efficacy of selected KIs was tested.

Heterogeneous signaling was observed with between 241 and 2764 phosphopeptides detected per cell line. Of 4853 identified phosphopeptides with 4229 phosphosites, 4459 phosphopeptides (4430 pY) were linked to 3605 class I sites (3525 pY). INKA analysis in single cell lines successfully pinpointed driver kinases (PDGFRA, JAK2, KIT and FLT3) corresponding with activating mutations present in these cell lines. Furthermore, potential receptor tyrosine kinase (RTK) drivers, undetected by standard molecular analyses, were identified in four cell lines (FGFR1 in KG-1 and KG-1a, PDGFRA in Kasumi-3, and FLT3 in MM6). These cell lines proved highly sensitive to specific KIs. Six AML cell lines without a clear RTK driver showed evidence of MAPK1/3 activation, indicative of the presence of activating upstream RAS mutations. Importantly, FLT3 phosphorylation was demonstrated in two clinical AML samples with a FLT3 internal tandem duplication (ITD) mutation.

Our data show the potential of pY-phosphoproteomics and INKA analysis to provide insight in AML TK signaling and identify hyperactive kinases as potential targets for treatment in AML cell lines. These results warrant future investigation of clinical samples to further our understanding of TK phosphorylation in relation to clinical response in the individual patient.

Coenzyme Q (Qn) is a vital lipid component of the electron transport chain that functions in cellular energy metabolism and as a membrane antioxidant. In the yeast Saccharomyces cerevisiae, coq1–coq9 deletion mutants are respiratory-incompetent, sensitive to lipid peroxidation stress, and unable to synthesize Q6. The yeast coq10 deletion mutant is also respiratory-deficient and sensitive to lipid peroxidation, yet it continues to produce Q6 at an impaired rate. Thus, Coq10 is required for the function of Q6 in respiration and as an antioxidant and is believed to chaperone Q6 from its site of synthesis to the respiratory complexes. In several fungi, Coq10 is encoded as a fusion polypeptide with Coq11, a recently identified protein of unknown function required for efficient Q6 biosynthesis. Because “fused” proteins are often involved in similar biochemical pathways, here we examined the putative functional relationship between Coq10 and Coq11 in yeast. We used plate growth and Seahorse assays and LC-MS/MS analysis to show that COQ11 deletion rescues respiratory deficiency, sensitivity to lipid peroxidation, and decreased Q6 biosynthesis of the coq10Δ mutant. Additionally, immunoblotting indicated that yeast coq11Δ mutants accumulate increased amounts of certain Coq polypeptides and display a stabilized CoQ synthome. These effects suggest that Coq11 modulates Q6 biosynthesis and that its absence increases mitochondrial Q6 content in the coq10Δcoq11Δ double mutant. This augmented mitochondrial Q6 content counteracts the respiratory deficiency and lipid peroxidation sensitivity phenotypes of the coq10Δ mutant. This study further clarifies the intricate connection between Q6 biosynthesis, trafficking, and function in mitochondrial metabolism.

Heat shock factor 1 (HSF1) regulates cellular adaptation to challenges such as heat shock and oxidative and proteotoxic stresses. We have recently reported a previously unappreciated role for HSF1 in the regulation of energy metabolism in fat tissues; however, whether HSF1 is differentially expressed in adipose depots and how its levels are regulated in fat tissues remain unclear. Here, we show that HSF1 levels are higher in brown and subcutaneous fat tissues than in those in the visceral depot and that HSF1 is more abundant in differentiated, thermogenic adipocytes. Gene expression experiments indicated that HSF1 is transcriptionally regulated in fat by agents that modulate cAMP levels, by cold exposure, and by pharmacological stimulation of β-adrenergic signaling. An in silico promoter analysis helped identify a putative response element for activating transcription factor 3 (ATF3) at −258 to −250 base pairs from the HSF1 transcriptional start site, and electrophoretic mobility shift and ChIP assays confirmed ATF3 binding to this sequence. Furthermore, functional assays disclosed that ATF3 is necessary and sufficient for HSF1 regulation. Detailed gene expression analysis revealed that ATF3 is one of the most highly induced ATFs in thermogenic tissues of mice exposed to cold temperatures or treated with the β-adrenergic receptor agonist CL316,243 and that its expression is induced by modulators of cAMP levels in isolated adipocytes. To the best of our knowledge, our results show for the first time that HSF1 is transcriptionally controlled by ATF3 in response to classic stimuli that promote heat generation in thermogenic tissues.

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a newly discovered class of signaling lipids with anti-inflammatory and anti-diabetic properties. However, the endogenous regulation of FAHFAs remains a pressing but unanswered question. Here, using MS-based FAHFA hydrolysis assays, LC-MS–based lipidomics analyses, and activity-based protein profiling, we found that androgen-induced gene 1 (AIG1) and androgen-dependent TFPI-regulating protein (ADTRP), two threonine hydrolases, control FAHFA levels in vivo in both genetic and pharmacologic mouse models. Tissues from mice lacking ADTRP (Adtrp-KO), or both AIG1 and ADTRP (DKO) had higher concentrations of FAHFAs particularly isomers with the ester bond at the 9th carbon due to decreased FAHFA hydrolysis activity. The levels of other lipid classes were unaltered indicating that AIG1 and ADTRP specifically hydrolyze FAHFAs. Complementing these genetic studies, we also identified a dual AIG1/ADTRP inhibitor, ABD-110207, which is active in vivo. Acute treatment of WT mice with ABD-110207 resulted in elevated FAHFA levels, further supporting the notion that AIG1 and ADTRP activity control endogenous FAHFA levels. However, loss of AIG1/ADTRP did not mimic the changes associated with pharmacologically administered FAHFAs on extent of upregulation of FAHFA levels, glucose tolerance, or insulin sensitivity in mice, indicating that therapeutic strategies should weigh more on FAHFA administration. Together, these findings identify AIG1 and ADTRP as the first endogenous FAHFA hydrolases identified and provide critical genetic and chemical tools for further characterization of these enzymes and endogenous FAHFAs to unravel their physiological functions and roles in health and disease.

The cellular energy sensor AMP-activated protein kinase (AMPK) is a metabolic regulator that mediates adaptation to nutritional variations to maintain a proper energy balance in cells. We show here that suckling-weaning and fasting-refeeding transitions in rodents are associated with changes in AMPK activation and the cellular energy state in the liver. These nutritional transitions were characterized by a metabolic switch from lipid to glucose utilization, orchestrated by modifications in glucose levels and the glucagon/insulin ratio in the bloodstream. We therefore investigated the respective roles of glucose and pancreatic hormones on AMPK activation in mouse primary hepatocytes. We found that glucose starvation transiently activates AMPK, whereas changes in glucagon and insulin levels had no impact on AMPK. Challenge of hepatocytes with metformin-induced metabolic stress strengthened both AMPK activation and cellular energy depletion under limited-glucose conditions, whereas neither glucagon nor insulin altered AMPK activation. Although both insulin and glucagon induced AMPKα phosphorylation at its Ser485/491 residue, they did not affect its activity. Finally, the decrease in cellular ATP levels in response to an energy stress was additionally exacerbated under fasting conditions and by AMPK deficiency in hepatocytes, revealing metabolic inflexibility and emphasizing the importance of AMPK for maintaining hepatic energy charge. Our results suggest that nutritional changes (i.e. glucose availability), rather than the related hormonal changes (i.e. the glucagon/insulin ratio), sensitize AMPK activation to the energetic stress induced by the dietary transition during fasting. This effect is critical for preserving the cellular energy state in the liver.

Triple-negative breast cancer (TNBC) is characterized by its aggressive biology, early metastatic spread, and poor survival outcomes. TNBC lacks expression of the targetable receptors found in other breast cancer subtypes, mandating use of cytotoxic chemotherapy. However, resistance to chemotherapy is a significant problem, encountered in about two-thirds of TNBC patients, and new strategies are needed to mitigate resistance. In this issue of the Journal of Biological Chemistry, Geck et al. report that TNBC cells are highly sensitive to inhibition of the de novo polyamine synthesis pathway and that inhibition of this pathway sensitizes cells to TNBC-relevant chemotherapy, uncovering new opportunities for addressing chemoresistance.

Archaic technology wasting time for Canberrans is in the target of new federal agency.

Two new regions of Microsoft's Azure cloud will open in Canberra on Tuesday.

6 November 2019 , Volume 95, Number 6

Research Event

Event participants

Michael Gasiorek, Professor of Economics, University of Sussex; Director, Interanalysis; Fellow, UK Trade Policy Observatory, University of Sussex
Julia Magntorn Garrett, Research Officer, UK Trade Policy Observatory, University of Sussex
Prof Jim Rollo, Deputy Director, UK Trade Policy Observatory, University of Sussex; Associate Fellow, Global Economy and Finance Department, Chatham House
Nicolo Tamberi, Research Officer in the Economics of Brexit, University of Sussex
L. Alan Winters, Professor of Economics, Director, UK Trade Policy Observatory, University of Sussex

10 December 2019

20 January 2020

How can democratic governments hold intelligence and security agencies to account when what they do is largely secret? Jamie Gaskarth explores how intelligence professionals view accountability in the context of 21st century politics. 

15 March 2020

15 April 2020

7 May 2020 , Volume 96, Number 3

Keisuke Mori
Apr 29, 2020; 0:jlr.RA120000803v1-jlr.RA120000803
Research Articles

Gemma Cadby
Apr 1, 2020; 61:537-545
Patient-Oriented and Epidemiological Research

Delphine Fontaine
Apr 7, 2020; 0:jlr.RA120000634v1-jlr.RA120000634
Research Articles

M John Chapman
Apr 15, 2020; 0:jlr.P119000543v1-jlr.P119000543
Patient-Oriented and Epidemiological Research

Chelsea DeLeon
May 1, 2020; 61:767-777
Research Articles

Dmitri Sviridov
May 1, 2020; 61:687-695
Thematic Reviews

Stephen G. Young
May 1, 2020; 61:589-590
Editorials

In this week's UK Tech Weekly Podcast host Matt Egan is joined by first time podder Tamlin Magee (1:50), online editor at ComputerworldUK.com, to discuss the UK tech implications of this year's Budget, including rural broadband and driverless cars. Then Christina Mercer, assistant online editor at Techworld.com, chats AlphaGo (10:00) and board games following the AI's historic win over world Go champion Lee Sedol. Later, resident Virtual Reality (VR) enthusiast and PCAdvisor.co.uk staff writer Lewis Painter discussed "the big three" VR headset release dates, pricing and features from HTC, Sony Playstation and Oculus Rift (19:00). Finally, UKTW Podcast regular David Price, acting editor at Macworld.co.uk chats about Apple's big upcoming event (28:45).  

See acast.com/privacy for privacy and opt-out information.

In this week's UK Tech Weekly Podcast host Matt Egan is joined by online editor at Techworld.com Scott Carey to discuss all of the news coming out of Microsoft's Build 2016 developer conference, before being joined by producer Chris to talk about the company's genocidal AI chatbot Tay's public meltdown (13:00). Then, acting editor at Macworld.co.uk David Price jumps in to discuss the apparent resolution to the Apple vs FBI fight (29:00).  

See acast.com/privacy for privacy and opt-out information.

Join host David Price for a dive into all things tech: Round 43. Things go mobile as Senior Staff Writer at PC Advisor and Macworld UK Henry Burrell tells us why Sky getting into the market is a big deal. Quad-play ahoy. Then fellow Senior Staff Writer Lewis Painter (14 mins) tells us why No Man's Sky is still making the headlines, this time for making stuff up. How far have companies taken false advertising in recent years? Third up is Techworld editor Charlotte Jee (25 mins) to talk about how the government has perhaps avoided taking responsibility when it comes to sex-ed and instead suggested it ban sexting - is that even possible? Listen on to find out.  

See acast.com/privacy for privacy and opt-out information.

The gang returns with an eclectic mix of tech chat. Can Nectome really download your thoughts - while killing you - to preserve your memories forever in the cloud? We didn't make this up.

Then we discuss the brand new Samsung Galaxy S9, phone cameras and crap AR before discussing how the UK should go about contracting a company to age check porn site users.

See acast.com/privacy for privacy and opt-out information.

We let one huge, scary story dominate proceedings before allowing two lighter-weight topics return the pod to its family friendly roots.

The Cambridge Analytica and Facebook scandal is decoded and discussed, with one podder especially susceptible to influence thanks to their insane third party app access numbers.

The gang then tackles Sea of Thieves, a return to form for Rare on Xbox, before Dom (with no spoilers) says just how bad Ready Player One is.

See acast.com/privacy for privacy and opt-out information.

This week it’s David Price in the hosting seat to dig into two meaty tech topics: how does Netflix buy and develop its massive content library, and why is Fortnite such a sensation?

Helping him dig into Netflix is Computerworld UK editor Scott Carey, with our new entertainment and lifestyle editor at Tech Advisor Dominic Preston joining in.

Then staff writer at Tech Advisor Sean Bradley is on hand to talk about how Fortnite has become such a sensation, and if it is built to last.

See acast.com/privacy for privacy and opt-out information.

Ether lipids (ELs) are lipids characterized by the presence of either an ether linkage (alkyl lipids) or a vinyl ether linkage (i.e. plasmalogens [Pls]) at the sn1 position of the glycerol backbone and they are enriched in PUFAs at the sn2 position. In this review, we highlight that ELs have various biological functions, act as a reservoir for second messengers (such as PUFAs), and have roles in many diseases. Some of the biological effects of ELs may be associated with their ability to regulate ion channels that control excitation-contraction/secretion/mobility coupling and therefore cell physiology. These channels are embedded in lipid membranes, and lipids can regulate their activities directly or indirectly as second messengers or by incorporating into membranes. Interestingly, ELs and EL-derived PUFAs have been reported to play a key role in several pathologies, including neurological disorders, cardiovascular diseases, and cancers. Investigations leading to a better understanding of their mechanisms of action in pathologies have opened a new field in cancer research. In summary, newly identified lipid regulators of ion channels, such as ELs and PUFAs, may represent valuable targets to improve disease diagnosis and advance the development of new therapeutic strategies for managing a range of diseases and conditions.

Atherogenic LDL particles are physicochemically and metabolically heterogeneous. Can bioactive lipid cargo differentiate LDL subclasses, and thus potential atherogenicity?  What is the effect of statin treatment? Obese, hypertriglyceridemic, hypercholesterolemic males (n=12; Lp(a) <10 mg/dL) received pitavastatin calcium (4mg/day) for 180 days in a single-phase, unblinded study. The lipidomic profiles (23 lipid classes) of five LDL subclasses fractionated from baseline and post-statin plasmas were determined by LC-MS. At baseline and on statin treatment, very small dense LDL (LDL5) was preferentially enriched (up to 3-fold) in specific lysophospholipids (lysophosphatidylcholine (LPC); lysophosphatidylinositol (LPI); lyso-platelet activating factor (LPC(O)); 9,0.2 and 0.14 mol/mol apoB respectively; all p<0.001 versus LDL1-4), suggesting  elevated inflammatory potential per particle. In contrast, lysophosphatidylethanolamine was uniformly distributed among LDL subclasses. Statin treatment markedly reduced absolute plasma concentrations of all LDL subclasses (up to 33.5%), including LPC, LPI and LPC(O) contents (up to -52%), consistent with reduction in cardiovascular risk. Despite such reductions, lipotoxic ceramide load per particle in LDL1-5 (1.5 - 3 mol/mol apoB; 3 - 7 mmol/mol phosphatidylcholine) was either conserved or elevated. Bioactive lipids may constitute biomarkers for the cardiometabolic risk associated with specific LDL subclasses in atherogenic dyslipidemia at baseline, and with residual risk on statin therapy.