The mammalian target of rapamycin inhibitor RAD001 (everolimus) synergizes with chemotherapeutic agents, ionizing radiation and proteasome inhibitors in pre-B acute lymphocytic leukemia.

BACKGROUND: Despite incremental improvements in outcomes for patients with acute lymphoblastic leukemia, significant numbers of patients still die from this disease. Mammalian target of rapamycin inhibitors have shown potential in vitro and in vivo as therapeutic agents against a range of tumors including acute lymphoblastic leukemia. DESIGN AND METHODS: Flow cytometry was used to evaluate drug-induced cell death in acute lymphoblastic leukemia cell lines and patients' samples. Human xenografts in immunocompromised mice were used to assess the in vivo effects of selected combinations. Pharmacological inhibitors and lentiviral small interfering ribonucleic acid knock-down of p53 were used to investigate the mechanism of cell killing involved. RESULTS: Synergistic interactions between RAD001 and cytotoxic agents were demonstrated in vitro and in vivo, with increased caspase-dependent killing. RAD001 suppressed p53 and p21 responses, while suppression of p53 did not prevent killing, indicating p53 independence. RAD001 and cytotoxic agents activated the JUN N-terminal kinase pathway and the combination further increased JUN N-terminal kinase activation. JUN N-terminal kinase inhibition reduced synergistic cell killing by cytotoxic agents and RAD001 in pre-B acute lymphoblastic leukemia cell lines and patients' samples. Bortezomib and MG132, which activate the JUN N-terminal kinase pathway, also synergized with RAD001 in killing pre-B acute lymphoblastic leukemia cells. Killing was greater when RAD001 was combined with proteasome inhibitors than with cytotoxic drugs. CONCLUSIONS: These observations suggest that combining mammalian target of rapamycin inhibitors with conventional chemotherapy or selected novel agents has the potential to improve clinical responses in patients with pre-B acute lymphoblastic leukemia.

Interaural-time-difference thresholds for broad band-limited pulses are affected by relative bandwidth not temporal envelope sharpness.

Humans are sensitive to interaural time differences (ITDs) conveyed by slow modulations on high-frequency carrier signals. Sensitivity appears to be affected by temporal envelope sharpness, but it is unclear if there is a limit to which sharpness affects sensitivity. Pulse trains were varied in relative bandwidth (re: critical bandwidths) and center frequency. ITD sensitivity increased with increasing bandwidth. There was no effect of center frequency when relative bandwidths were analyzed, suggesting that the temporal envelope sharpness (concomitantly absolute bandwidth in Hz) did not affect performance. Rather, sensitivity was most easily explained by recruitment of additional auditory channels.

wEight chanGes, caRdio-mEtabolic risks and morTality in patients with hyperthyroidism (EGRET): a protocol for a CPRD-HES linked cohort study.

INTRODUCTION: Hyperthyroidism is a common condition affecting up to 3% of the UK population. Treatment improves symptoms and reduces the risk of atrial fibrillation and stroke that contribute to increased mortality. The most common symptom is weight loss, which is reversed during treatment. However, the weight regain may be excessive, contributing to increased risk of obesity. Current treatment options include antithyroid drugs, radioiodine and thyroidectomy. Whether there are differences in either weight change or the long-term cardiometabolic risk between the three treatments is unclear. METHODS AND ANALYSIS: The study will establish the natural history of weight change in hyperthyroidism, investigate the risk of obesity and risks of cardiometabolic conditions and death relative to the treatment. The data on patients diagnosed with hyperthyroidism between 1 January 1996 and 31 December 2015 will come from Clinical Practice Research Datalink linked to Hospital Episode Statistics and Office of National Statistics Death Registry. The weight changes will be modelled using a flexible joint modelling, accounting for mortality. Obesity prevalence in the general population will be sourced from Health Survey for England and compared with the post-treatment prevalence of obesity in patients with hyperthyroidism. The incidence and time-to-event of major adverse cardiovascular events, other cardiometabolic outcomes and mortality will be compared between the treatments using the inverse propensity weighting model. Incidence rate ratios of outcomes will be modelled with Poisson regression. Time to event will be analysed using Cox proportional hazards model. A competing risks approach will be adopted to estimate comparative incidences to allow for the impact of mortality. ETHICS AND DISSEMINATION: The study will bring new knowledge on the risk of developing obesity, cardiometabolic morbidity and mortality following treatment for hyperthyroidism to inform clinical practice and public health policies. The results will be disseminated via open-access peer-reviewed publications and directly to the patients and public groups (Independent Scientific Advisory Committee protocol approval #20_000185).

mRNA vaccination in people over 80 years of age induces strong humoral immune responses against SARS-CoV-2 with cross neutralization of P.1 Brazilian variant.

Age is the major risk factor for mortality after SARS-CoV-2 infection and older people have received priority consideration for COVID-19 vaccination. However, vaccine responses are often suboptimal in this age group and few people over the age of 80 years were included in vaccine registration trials. We determined the serological and cellular response to spike protein in 100 people aged 80-96 years at 2 weeks after the second vaccination with the Pfizer BNT162b2 mRNA vaccine. Antibody responses were seen in every donor with high titers in 98%. Spike-specific cellular immune responses were detectable in only 63% and correlated with humoral response. Previous SARS-CoV-2 infection substantially increased antibody responses after one vaccine and antibody and cellular responses remained 28-fold and 3-fold higher, respectively, after dual vaccination. Post-vaccine sera mediated strong neutralization of live Victoria infection and although neutralization titers were reduced 14-fold against the P.1 variant first discovered in Brazil they remained largely effective. These data demonstrate that the mRNA vaccine platform delivers strong humoral immunity in people up to 96 years of age and retains broad efficacy against the P.1 variant of concern.

mTOR inhibition by everolimus in childhood acute lymphoblastic leukemia induces caspase-independent cell death.

Increasingly, anti-cancer medications are being reported to induce cell death mechanisms other than apoptosis. Activating alternate death mechanisms introduces the potential to kill cells that have defects in their apoptotic machinery, as is commonly observed in cancer cells, including in hematological malignancies. We, and others, have previously reported that the mTOR inhibitor everolimus has pre-clinical efficacy and induces caspase-independent cell death in acute lymphoblastic leukemia cells. Furthermore, everolimus is currently in clinical trial for acute lymphoblastic leukemia. Here we characterize the death mechanism activated by everolimus in acute lymphoblastic leukemia cells. We find that cell death is caspase-independent and lacks the morphology associated with apoptosis. Although mitochondrial depolarization is an early event, permeabilization of the outer mitochondrial membrane only occurs after cell death has occurred. While morphological and biochemical evidence shows that autophagy is clearly present it is not responsible for the observed cell death. There are a number of features consistent with paraptosis including morphology, caspase-independence, and the requirement for new protein synthesis. However in contrast to some reports of paraptosis, the activation of JNK signaling was not required for everolimus-induced cell death. Overall in acute lymphoblastic leukemia cells everolimus induces a cell death that resembles paraptosis.