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Background: Surgery for urological cancers is associated with high complication rates and survivors commonly experience fatigue, reduced physical ability and quality of life. High-intensity interval training (HIIT) as surgical prehabilitation has been proven effective for improving the cardiorespiratory fitness (CRF) of urological cancer patients, however the mechanistic basis of this favourable adaptation is undefined. Thus, we aimed to assess the mechanisms of physiological responses to HIIT as surgical prehabilitation for urological cancer., Methods: Nineteen male patients scheduled for major urological surgery were randomised to complete 4-weeks HIIT prehabilitation (71.6 ± 0.75 years, BMI: 27.7 ± 0.9 kg·m 2 ) or a no-intervention control (71.8 ± 1.1 years, BMI: 26.9 ± 1.3 kg·m 2 ). Before and after the intervention period, patients underwent m. vastus lateralis biopsies to quantify the impact of HIIT on mitochondrial oxidative phosphorylation (OXPHOS) capacity, cumulative myofibrillar muscle protein synthesis (MPS) and anabolic, catabolic and insulin-related signalling., Results: OXPHOS capacity increased with HIIT, with increased expression of electron transport chain protein complexes (C)-II (p = 0.010) and III (p = 0.045); and a significant correlation between changes in C-I (r = 0.80, p = 0.003), C-IV (r = 0.75, p = 0.008) and C-V (r = 0.61, p = 0.046) and changes in CRF. Neither MPS (1.81 ± 0.12 to 2.04 ± 0.14%·day -1 , p = 0.39) nor anabolic or catabolic proteins were upregulated by HIIT (p > 0.05). There was, however, an increase in phosphorylation of AS160 Thr642 (p = 0.046) post-HIIT., Conclusions: A HIIT surgical prehabilitation regime, which improved the CRF of urological cancer patients, enhanced capacity for skeletal muscle OXPHOS; offering potential mechanistic explanation for this favourable adaptation. HIIT did not stimulate MPS, synonymous with the observed lack of hypertrophy. Larger trials pairing patient-centred and clinical endpoints with mechanistic investigations are required to determine the broader impacts of HIIT prehabilitation in this cohort, and to inform on future optimisation (i.e., to increase muscle mass)., (© 2023. The Author(s).)

Type II diabetes (T2D) and specific cancers share many risk factors, however, the molecular mechanisms underlying these connections are often not well-understood. BCDIN3D is an RNA modifying enzyme that methylates specific precursor microRNAs and tRNA His . In addition to breast cancer, BCDIN3D may also be linked to metabolism, as its gene locus is associated with obesity and T2D. In order to uncover metabolic pathways regulated by BCDIN3D in cancer, we performed an unbiased analysis of the metabolome, transcriptome, and proteome of breast cancer cells depleted for BCDIN3D. Intersection of these analyses showed that BCDIN3D-depleted cells have increased levels of Fructose 1,6 Bisphosphate (F1,6-BP), the last six-carbon glycolytic intermediate accompanied by reduced glycolytic capacity. We further show that elevated F1,6-BP is due to downregulation of Aldolase C (ALDOC), an enzyme that cleaves F1,6-BP mainly in the brain, but whose high expression/amplification is associated with poor prognosis in breast cancer. BCDIN3D regulates ALDOC through a non-canonical mechanism involving the crucial let-7 microRNA family and its target site on the 3'UTR of ALDOC. Overall, our results reveal an important connection between BCDIN3D, let-7 and glycolysis that may be relevant to breast cancer, obesity, and T2D.

Objectives: To assess the efficacy of high-intensity interval training (HIIT) for improving cardiorespiratory fitness (CRF) in patients awaiting resection for urological malignancy within four weeks., Subjects/patients and Methods: A randomised control trial of consecutive patients aged (>65 years) scheduled for major urological surgery in a large secondary referral centre in a UK hospital. The primary outcome is change in anaerobic threshold (VO 2AT ) following HIIT vs. standard care., Results: Forty patients were recruited (mean age 72 years, male (39): female (1)) with 34 completing the protocol. Intention to treat analysis showed significant improvements in anaerobic threshold (VO 2AT ; mean difference (MD) 2.26 ml/kg/min (95% CI 1.25-3.26)) following HIIT. Blood pressure (BP) also significantly reduced in following: HIIT (SBP: -8.2 mmHg (95% CI -16.09 to -0.29) and DBP: -6.47 mmHg (95% CI -12.56 to -0.38)). No reportable adverse safety events occurred during HIIT and all participants achieved >85% predicted maximum heart rate during sessions, with protocol adherence of 84%., Conclusions: HIIT can improve CRF and cardiovascular health, representing clinically meaningful and achievable pre-operative improvements. Larger randomised trials are required to investigate the efficacy of prehabilitation HIIT upon different cancer types, post-operative complications, socio-economic impact and long-term survival.

Pediatric cancer treatment often involves chemotherapy and radiation, where off-target effects can include skeletal muscle decline. The effect of such treatments on juvenile skeletal muscle growth has yet to be investigated. We employed a small animal irradiator to administer fractionated hindlimb irradiation to juvenile mice bearing implanted rhabdomyosarcoma (RMS) tumors. Hindlimb-targeted irradiation (3 × 8.2 Gy) of 4-week-old mice successfully eliminated RMS tumors implanted one week prior. After establishment of this preclinical model, a cohort of tumor-bearing mice were injected with the chemotherapeutic drug, vincristine, alone or in combination with fractionated irradiation (5 × 4.8 Gy). Single myofiber analysis of fast-contracting extensor digitorum longus (EDL) and slow-contracting soleus (SOL) muscles was conducted 3 weeks post-treatment. Although a reduction in myofiber size was apparent, EDL and SOL myonuclear number were differentially affected by juvenile irradiation and/or vincristine treatment. In contrast, a decrease in myonuclear domain (myofiber volume/myonucleus) was observed regardless of muscle or treatment. Thus, inhibition of myofiber hypertrophic growth is a consistent feature of pediatric cancer treatment.

The human GABA B receptor-a member of the class C family of G-protein-coupled receptors (GPCRs)-mediates inhibitory neurotransmission and has been implicated in epilepsy, pain and addiction 1 . A unique GPCR that is known to require heterodimerization for function 2-6 , the GABA B receptor has two subunits, GABA B1 and GABA B2 , that are structurally homologous but perform distinct and complementary functions. GABA B1 recognizes orthosteric ligands 7,8 , while GABA B2 couples with G proteins 9-14 . Each subunit is characterized by an extracellular Venus flytrap (VFT) module, a descending peptide linker, a seven-helix transmembrane domain and a cytoplasmic tail 15 . Although the VFT heterodimer structure has been resolved 16 , the structure of the full-length receptor and its transmembrane signalling mechanism remain unknown. Here we present a near full-length structure of the GABA B receptor, captured in an inactive state by cryo-electron microscopy. Our structure reveals several ligands that preassociate with the receptor, including two large endogenous phospholipids that are embedded within the transmembrane domains to maintain receptor integrity and modulate receptor function. We also identify a previously unknown heterodimer interface between transmembrane helices 3 and 5 of both subunits, which serves as a signature of the inactive conformation. A unique 'intersubunit latch' within this transmembrane interface maintains the inactive state, and its disruption leads to constitutive receptor activity.

Measures of microbial growth, used as indicators of cellular stress, are sometimes quantified at a single time-point. In reality, these measurements are compound representations of length of lag, exponential growth-rate, and other factors. Here, we investigate whether length of lag phase can act as a proxy for stress, using  a number of model systems (Aspergillus penicillioides; Bacillus subtilis; Escherichia coli; Eurotium amstelodami, E. echinulatum, E. halophilicum, and E. repens; Mrakia frigida; Saccharomyces cerevisiae; Xerochrysium xerophilum; Xeromyces bisporus) exposed to mechanistically distinct types of cellular stress including low water activity, other solute-induced stresses, and dehydration-rehydration cycles. Lag phase was neither proportional to germination rate for X. bisporus (FRR3443) in glycerol-supplemented media (r 2  = 0.012), nor to exponential growth-rates for other microbes. In some cases, growth-rates varied greatly with stressor concentration even when lag remained constant. By contrast, there were strong correlations for B. subtilis in media supplemented with polyethylene-glycol 6000 or 600 (r 2  = 0.925 and 0.961), and for other microbial species. We also  analysed data from independent studies of food-spoilage fungi under glycerol stress (Aspergillus aculeatinus and A. sclerotiicarbonarius); mesophilic/psychrotolerant bacteria under diverse, solute-induced stresses (Brochothrix thermosphacta, Enterococcus faecalis, Pseudomonas fluorescens, Salmonella typhimurium, Staphylococcus aureus); and fungal enzymes under acid-stress (Terfezia claveryi lipoxygenase and Agaricus bisporus tyrosinase). These datasets also exhibited diversity, with some strong- and moderate correlations between length of lag and exponential growth-rates; and sometimes none. In conclusion, lag phase is not  a reliable measure of stress because length of lag and growth-rate inhibition are sometimes highly correlated, and sometimes not at all.

Cranial irradiation is the main therapeutic treatment for primary and metastatic malignancies in the brain. However, cranial radiation therapy produces long-term impairment in memory, information processing, and attention that contribute to a decline in quality of life. The hippocampal neural network is fundamental for proper storage and retrieval of episodic and spatial memories, suggesting that hippocampal signaling dysfunction could be responsible for the progressive memory deficits observed following irradiation. Previous rodent studies demonstrated that irradiation induces significant loss in dendritic spine number, alters spine morphology, and is associated with behavioral task deficits. Additionally, the literature suggests a common mechanism in which synaptic elimination via microglial-mediated phagocytosis is complement dependent and associated with cognitive impairment in aging as well as disease. We demonstrate sexual dimorphisms in irradiation-mediated alterations of microglia activation markers and dendritic spine density. Further, we find that the significant dendritic spine loss observed in male mice following irradiation is microglia complement receptor 3 (CR3)-dependent. By identifying sex-dependent cellular and molecular factors underlying irradiation-mediated spine loss, therapies can be developed to counteract irradiation-induced cognitive decline and improve patient quality of life.

Space travel will expose people to high-energy, heavy particle radiation, and the cognitive deficits induced by this exposure are not well understood. To investigate the short-term effects of space radiation, we irradiated 4-month-old Alzheimer's disease (AD)-like transgenic (Tg) mice and wildtype (WT) littermates with a single, whole-body dose of 10 or 50 cGy 56 Fe ions (1 GeV/u) at Brookhaven National Laboratory. At ~1.5 months post irradiation, behavioural testing showed sex-, genotype-, and dose-dependent changes in locomotor activity, contextual fear conditioning, grip strength, and motor learning, mainly in Tg but not WT mice. There was little change in general health, depression, or anxiety. Two months post irradiation, microPET imaging of the stable binding of a translocator protein ligand suggested no radiation-specific change in neuroinflammation, although initial uptake was reduced in female mice independently of cerebral blood flow. Biochemical and immunohistochemical analyses revealed that radiation reduced cerebral amyloid-β levels and microglia activation in female Tg mice, modestly increased microhemorrhages in 50 cGy irradiated male WT mice, and did not affect synaptic marker levels compared to sham controls. Taken together, we show specific short-term changes in neuropathology and behaviour induced by 56 Fe irradiation, possibly having implications for long-term space travel.

Neurofibromatosis type 1 (NF1) is an inherited disease in which affected patients are predisposed to develop benign Schwann cell (SC) tumours called neurofibromas. In the mouse, loss of Nf1 in the SC lineage causes neurofibroma formation. The tyrosine kinase receptor EGFR is expressed in Schwann cell precursors (SCP), which have been implicated in plexiform neurofibroma initiation. To test if EGFR activity affects neurofibroma initiation, size, and/or number, we studied mice expressing human EGFR in SCs and SCP in the context of mice that form neurofibromas. Neurofibroma number increased in homozygous CNP-hEGFR mice versus heterozygous littermates, and neurofibroma number and size increased when CNP-hEGFR was crossed to Nf1 fl/fl ;DhhCre mice. Conversely, diminished EGFR signalling in Nf1 fl/fl ;DhhCre;Wa2/+ mice decreased neurofibroma number. In vivo transplantation verified the correlation between EGFR activity and neurofibroma formation. Mechanistically, expression of CNP-hEGFR increased SCP/neurofibroma-initiating cell self-renewal, a surrogate for tumour initiation, and activated P-Stat3. Further, Il-6 reinforced Jak2/Stat3 activation in SCPs and SCs. These gain- and loss-of function assays show that levels of tyrosine kinase expression in SCPs modify neurofibroma initiation.

A snow-line is the region of a protoplanetary disk at which a major volatile, such as water or carbon monoxide, reaches its condensation temperature. Snow-lines play a crucial role in disk evolution by promoting the rapid growth of ice-covered grains. Signatures of the carbon monoxide snow-line (at temperatures of around 20 kelvin) have recently been imaged in the disks surrounding the pre-main-sequence stars TW Hydra and HD163296 (refs 3, 10), at distances of about 30 astronomical units (au) from the star. But the water snow-line of a protoplanetary disk (at temperatures of more than 100 kelvin) has not hitherto been seen, as it generally lies very close to the star (less than 5 au away for solar-type stars). Water-ice is important because it regulates the efficiency of dust and planetesimal coagulation, and the formation of comets, ice giants and the cores of gas giants. Here we report images at 0.03-arcsec resolution (12 au) of the protoplanetary disk around V883 Ori, a protostar of 1.3 solar masses that is undergoing an outburst in luminosity arising from a temporary increase in the accretion rate. We find an intensity break corresponding to an abrupt change in the optical depth at about 42 au, where the elevated disk temperature approaches the condensation point of water, from which we conclude that the outburst has moved the water snow-line. The spectral behaviour across the snow-line confirms recent model predictions: dust fragmentation and the inhibition of grain growth at higher temperatures results in soaring grain number densities and optical depths. As most planetary systems are expected to experience outbursts caused by accretion during their formation, our results imply that highly dynamical water snow-lines must be considered when developing models of disk evolution and planet formation.

The hypocretin/orexin (HCRT) system has been associated with both positive and negative drug reinforcement, implicating HCRT receptor 1 (HCRT-R1) signaling in drug-related behaviors for all major drug classes, including opioids. However, to date there are limited studies investigating the role of HCRT receptor 2 (HCRT-R2) signaling in compulsive-like drug seeking. Escalation of drug intake with extended access has been suggested to model the transition from controlled drug use to compulsive-like drug seeking/taking. The current study examined the effects of a HCRT-R2 antagonist, NBI-80713, on heroin self-administration in rats allowed short- (1 h; ShA) or long- (12 h; LgA) access to intravenous heroin self-administration. Results indicate that systemically administered NBI-80713 dose-dependently decreased heroin self-administration in LgA, but not in ShA, animals. Quantitative PCR analyses showed an increase in Hcrtr2 mRNA levels in the central amygdala, a stress-related brain region, of LgA rats. These observations suggest a functional role for HCRT-R2 signaling in compulsive-like heroin self-administration associated with extended access and indicate HCRT-R2 antagonism as a potential pharmacological target for the treatment of heroin dependence.

Mutations in the neurofibromatosis type 1 (NF1) tumor suppressor gene are common in cancer and can cause resistance to therapy. Using transcriptome analysis we identified MAF as an NF1- regulated transcription factor and verified MAF regulation through RAS/MAPK/AP-1 signaling in malignant peripheral nerve sheath tumor (MPNST) cell lines. MAF was also downregulated in human MPNST. Acute re-expression of MAF promoted expression of glial differentiation markers in MPNST cells in vitro, decreased self-renewal of embryonic precursors and transiently affected tumor cell phenotypes in vitro by increasing MPNST cell death and reducing metabolic activity and anchorage-independent growth. Paradoxically, chronic MAF overexpression enhanced MPNST cell tumor growth in vivo, correlating with elevated pS6 in vitro and in vivo. RAD001 blocked MAF-mediated tumor growth, and MAF regulated the mTOR pathway through DEPTOR. MAPK inhibition with NF1 loss of function is predicted to show limited efficacy due to reactivation of mTOR signaling via MAF.

Basic fibroblast growth factor (bFGF) inhibits radiation-induced apoptosis, and radioprotects haematopoietic, cartilage growth plate, pulmonary and gastrointestinal tissues. Conversely, chronic overexpression of bFGF may promote fibrosis. We measured the endogenous circulating bFGF in blood of patients undergoing conditioning TBI. Twenty-six patients with haematopoietic malignancies were conditioned with cyclophosphamide/TBI for allogeneic BMT. Daily blood samples were collected each morning prior to, during, and for several days after TBI. bFGF levels in plasma of normal volunteers are 0.8-26 pg/ml. bFGF was below detectability in 22%, 30% and 45% of patients pre-TBI, during TBI or post-TBI respectively. Mean circulating plasma levels of bFGF decreased from a median of 52 pg/ml pre-TBI to 26 pg/ml during TBI, and to 5 pg/ml post-TBI. Among the 26 patients, 13 had more than one non-detectable plasma bFGF level, an additional five had at least one non-detectable level, and only eight patients had detectable levels in all daily samples. Naturally high levels of bFGF were observed in some patients undergoing fractionated TBI. In contrast, as many as 79% of patients had low bFGF levels in one or more samples. The impact of endogenous bFGF on the tolerance of normal tissues to irradiation is unknown, and warrants further study.

The CDKN2 tumor suppressor gene encodes an inhibitor of type D cyclin dependent kinases. CDKN2 is homozygously deleted in approximately 25% of nonsmall cell lung cancer (NSCLC) cell lines and these deletions are associated with advanced stage cancer. Conflicting reports of the frequency of CDKN2 alterations in NSCLC tumors prompted us to examine the relationship of these alterations and those of the related gene, MTS2, with patient stage and site of cancer. One hundred twenty-five NSCLC samples (71 cell lines and 54 tumors) were examined by PCR-SSCP. Twenty of 71 (28%) tumor cell lines had homozygous deletions, and six (8%) had point mutations compared to 4 (7%) with point mutations among 54 tumor samples. All mutations were observed in tumors or cell lines from patients with stage III or IV disease. Two patients with no mutations in their primary tumor had a CDKN2 point mutation detected in a metastatic tumor. Point mutations were G:C to T:A transversion on the coding strand in five of 10 and resulted in nonsense mutations in seven of 10. Undetectable CDKN2 mRNA, in the absence of detectable genetic alteration, was noted in a similar fraction of cell lines derived from patients with stage I or II disease [two of seven (29%)] and stage III or IV disease [15 of 49 (31%)]. Homozygous deletion of MTS2 was found in 17 of 20 cell lines with CDKN2 deletions; no point mutations of MTS2 were identified by SSCP in the 125 samples. Thus, CDKN2 is a frequent target of genetic alterations at 9p21 in NSCLC. Both deletions and point mutations of CDKN2 are closely associated with tumor dissemination.