Loss of PTEN Promotes Resistance to T Cell-Mediated Immunotherapy

T cell-mediated immunotherapies are promising cancer treatments. However, most patients still fail to respond to these therapies. The molecular determinants of immune resistance are poorly understood. We show that loss of PTEN in tumor cells in preclinical models of melanoma inhibits T cell-mediated tumor killing and decreases T-cell trafficking into tumors. In patients, PTEN loss correlates with decreased T-cell infiltration at tumor sites, reduced likelihood of successful T-cell expansion from resected tumors, and inferior outcomes with PD-1 inhibitor therapy. PTEN loss in tumor cells increased the expression of immunosuppressive cytokines, resulting in decreased T-cell infiltration in tumors, and inhibited autophagy, which decreased T cell-mediated cell death. Treatment with a selective PI3Kβ inhibitor improved the efficacy of both anti-PD-1 and anti-CTLA-4 antibodies in murine models. Together, these findings demonstrate that PTEN loss promotes immune resistance and support the rationale to explore combinations of immunotherapies and PI3K-AKT pathway inhibitors.

SIGNIFICANCE

This study adds to the growing evidence that oncogenic pathways in tumors can promote resistance to the antitumor immune response. As PTEN loss and PI3K-AKT pathway activation occur in multiple tumor types, the results support the rationale to further evaluate combinatorial strategies targeting the PI3K-AKT pathway to increase the efficacy of immunotherapy.

Increased Tumor Glycolysis Characterizes Immune Resistance to Adoptive T Cell Therapy

Adoptive T cell therapy (ACT) produces durable responses in some cancer patients; however, most tumors are refractory to ACT and the molecular mechanisms underlying resistance are unclear. Using two independent approaches, we identified tumor glycolysis as a pathway associated with immune resistance in melanoma. Glycolysis-related genes were upregulated in melanoma and lung cancer patient samples poorly infiltrated by T cells. Overexpression of glycolysis-related molecules impaired T cell killing of tumor cells, whereas inhibition of glycolysis enhanced T cell-mediated antitumor immunity in vitro and in vivo. Moreover, glycolysis-related gene expression was higher in melanoma tissues from ACT-refractory patients, and tumor cells derived from these patients exhibited higher glycolytic activity. We identified reduced levels of IRF1 and CXCL10 immunostimulatory molecules in highly glycolytic melanoma cells. Our findings demonstrate that tumor glycolysis is associated with the efficacy of ACT and identify the glycolysis pathway as a candidate target for combinatorial therapeutic intervention.

GABA-immunoreactive neurons in the dorsal horn of the rat spinal cord

An antiserum to GABA was used on semithin resin-embedded sections of rat dorsal horn. Immunoreactive neurons were evenly distributed throughout laminae I-III and constituted between 24 and 33% of the total neuronal population within three laminae. Fifty Golgi-stained cells in lamina II were tested with the antiserum. Most of the islet cells examined were immunoreactive, although some small islet cells were not. None of the 14 stalked cells tested was immunoreactive. These results provide further evidence that the stalked and islet cells of lamina II form two distinct functional classes and suggest that the islet cells function as inhibitory interneurons.

Low- and conventional-dose maintenance therapy with fluphenazine decanoate. Two-year outcome

We evaluated the effectiveness and the side effects of what we defined as low (5-mg) and conventional (25-mg) doses of fluphenazine decanoate administered every two weeks in a double-blind comparison. Subjects were 66 patients who fulfilled DSM-III criteria for schizophrenic disorder. Evaluation of the survival with each dose revealed no significant difference at one year, but significantly better survival was seen with the 25-mg dose (64%) than the 5-mg dose (31%) at two years. There was no significant difference in survival when the clinician was permitted to make a dosage adjustment up to 10 mg in the low-dose group and 50 mg in the higher-dose group when the patient demonstrated evidence of a symptomatic exacerbation. Patients assigned to the higher dose appeared to feel more uncomfortable during the early months of the study, as indicated by significantly higher scores on subscales of the Hopkins Symptom Checklist-90R and higher side effect scores for retardation and akathisia. Implications for clinical practice are discussed.

Decreased muscarinic1 receptors in the dorsolateral prefrontal cortex of subjects with schizophrenia

To test the hypothesis that muscarinic receptors are involved in the pathology of schizophrenia, we measured muscarinic(1) (M1R) and muscarinic(4)(M4R) protein and mRNA as well as [(3)H]pirenzepine binding in Brodmann's areas (BA) 9 and 40 obtained postmortem from 20 schizophrenic and 20 age/sex-matched control subjects. There was a significant decrease in [(3)H]pirenzepine binding to BA 9 (mean +/- SEM: 151 +/- 15 vs 195 +/- 10 fmol mg(-1) ETE; P< 0.02), but not BA 40 (143 +/- 13 vs 166 +/- 11 fmol mg(-1) ETE), from subjects with schizophrenia. The level of M1R protein (0.11 +/- 0.007 vs 0.15 +/- 0.008 OD; P < 0.01), but not M4R protein, was decreased in BA9 from schizophrenic subjects with neither receptor protein being altered in BA 40. The level of M1R mRNA was decreased in BA 9 (30 +/- 7.0 vs 79 +/- 14 dpm x 10(3) mg(-1) ETE, P < 0.01) and BA 40 (28 +/- 5.9 vs 99 +/- 14, P < 0.01) with schizophrenia but M4R mRNA was only decreased in BA 40 (48 +/- 6.6 vs 89 +/- 9.9, P < 0.005). These data suggest that the M1R, at least in the dorsolateral prefrontal cortex, may have a role in the pathology of schizophrenia.

Alcohol tolerance: An ecological parameter in the relative success of Drosophila melanogaster and Drosophila simulans

Laboratory experiments have shown D. melanogaster adults to be more tolerant to alcohol in the environment than D. simulans, with the females being more tolerant than the males of their species. Larval development on alcohol supplemented media also demonstrated an increased tolerance by D. melanogaster although the effect was not as clear cut as for the adult survival. Oviposition choice experiments demonstrated a marked rejection of alcohol impregnated laying sites by D. simulans when compared to standard medium sites. D. melanogaster showed a slight preference for alcohol supplemented sites.Collections in the maturation cellar of a vineyard produced, with the exception of a single D. simulans fly, entirely D. melanogaster adults while larvae and pupae from the cellar were also all D. melanogaster. Away from the alcohol resource, outside the cellar, both species were collected with D. simulans being the more common. However, the outside distribution of the two species was affected by alcohol fumes during vintage, as was the distribution of the sexes of D. melanogaster, with the more tolerant species or sex being closer to the source. The field results were thus in agreement with the laboratory predictions that D. melanogaster is better able to utilize an alcohol resource than D. simulans.

Farm exposure in utero may protect against asthma, hay fever and eczema

The aim of the present study was to assess which factors contribute to the lower prevalence of allergic diseases in farmers' children, and the importance of timing of exposure. In a cross-sectional questionnaire survey, asthma symptoms, hay fever and eczema were assessed, as well as current, early and prenatal farm-related exposures in 1,333 farmers' children and 566 reference children aged 5-17 yrs. Farmers' children had a lower incidence of asthma symptoms and eczema. Current and maternal exposure during pregnancy to animals and/or grain and hay reduced the risk of asthma symptoms, hay fever and eczema. The exposure-response association for maternal exposure was nonlinear for most outcomes. After mutual adjustment, the effects of prenatal exposure remained unchanged whereas current exposure remained protective only for asthma medication, asthma ever and hay fever. Exposure during the first 2 yrs was not associated with symptoms, after controlling for prenatal exposure. A combination of prenatal and current exposure was most strongly associated with wheeze (odds ratio (OR) 0.48, 95% confidence interval (CI) 0.28-0.80), asthma medication (OR 0.50, 95% CI 0.30-0.82), asthma ever (OR 0.50, 95% CI 0.33-0.76), hay fever (OR 0.47, 95% CI 0.30-0.73) and eczema (OR 0.46, 95% CI 0.30-0.70). Prenatal exposure may contribute to the low prevalence of asthma, hay fever and eczema in farmers' children, but continued exposure may be required to maintain optimal protection.

Mass mortality and its environmental and evolutionary consequences

The latest Mesozoic and earliest Tertiary sediments at Deep Sea Drilling Project site 524 provide an amplified record of environmental and biostratographic changes at the end of Cretaceous. Closely spaced samples, representing time intervals as short as 10(2) or 10(3) years, were analyzed for their bulk carbonate and trace-metal compositions, and for oxygen and carbon isotopic compositions. The data indicate that at the end of Cretaceous, when a high proportion of the ocean's planktic organisms were eliminated, an associated reduction in productivity led to a partial transfer of dissolved carbon dioxide from the oceans to the atmosphere. This resulted in a large increase of the atmospheric carbon dioxide during the next 50,000 years, which is believed to have caused a temperature rise revealed by the oxygen-isotope data. The lowermost Tertiary sediments at site 524 include fossils with Cretaceous affinities, which may include both reworked individuals and some forms that survived for a while after the catastrophe. Our data indicate that many of the Cretaceous pelagic organisms became extinct over a period of a few tens of thousands of years, and do not contradict the scenario of cometary impact as a cause of mass mortality in the oceans, as suggested by an iridium anomaly at the Cretaceous-Tertiary boundary.

Costs and benefits of two doses of fluphenazine

The relative costs and benefits of low- and conventional-dose neuroleptic maintenance therapy were evaluated in a double-blind comparison of 5 and 25 mg of fluphenazine decanoate administered every two weeks. Subjects were 50 patients fulfilling DSM-III criteria for schizophrenic disorder who had been successfully maintained with 25 mg or less of fluphenazine decanoate. A one-year survival analysis disclosed that there were no statistically significant differences between the two doses insofar as preventing relapse. Patients receiving the higher dose appeared to feel more uncomfortable, as indicated by higher scores on subscales of the Hopkins Symptom Checklist-90. In addition, patients receiving the higher dose had higher side-effect scores. These findings suggest that a substantial proportion of patients who are presently maintained with 25 mg or less of fluphenazine decanoate every two weeks will do just as well with as little as 5 mg.

Diazinon resistance, fluctuating asymmetry and fitness in the Australian sheep blowfly, lucilia cuprina

Genetic evidence suggests that the evolution of resistance to the insecticide diazinon in Lucilia cuprina initially produced an increase in asymmetry. At that time resistant flies were presumed to be at a selective disadvantage in the absence of diazinon. Subsequent evolution in natural populations selected modifiers to ameliorate these effects. The fitness and fluctuating asymmetry levels of resistant flies are currently similar to those of susceptibles. Previous genetic analyses have shown the fitness modifier to co-segregate with the region of chromosome III marked by the white eyes, w, locus, unlinked to the diazinon resistance locus, Rop-1, on chromosome IV. This study maps the asymmetry modifier to the same region, shows, as in the case of the fitness modifier, its effect to be dominant and presents data consistent with the fitness/asymmetry modifier being the same gene (gene complex). These results suggest changes in fluctuating asymmetry reflect changes in fitness.

Prospective identification and triage of nonemergency patients out of an emergency department: a 5-year study

STUDY OBJECTIVE

To determine whether nonemergency patients can be prospectively identified by triage nurses and safely triaged out of the emergency department without treatment.

METHODS

All adult patients (16 years or older) who presented to a university ED were provided an evaluation by a triage nurse. For a patient's case to be defined as nonemergency, four criteria were required: vital signs within a specific range, presence of 1 of 50 potentially nonemergent chief complaints, absence of key indicators found on screening examination, and absence of chest pain, abdominal pain, any severe pain, and inability to walk. Between July 1988 and July 1993, patients who satisfied these criteria were defined as nonemergency, refused care in the ED, and triaged out of the ED. Patients were referred to off-site clinics. The clinics had agreed to see patients in advance of the study, and the referral lists were frequently updated. Outcome data were obtained by telephone surveys to both triaged individuals and other health care providers.

RESULTS

In this 5-year study, 176,074 adults presented to the ambulatory triage area in the ED, and 31,165 (18%) were defined as nonemergency, were not treated, and were referred elsewhere. Letters and telephone calls to all referral clinics, eight local EDs, and the coroner's office identified no instances of gross mistriage and only a small number of insignificant adverse outcomes. Telephone follow-up to individuals triaged away was successful in 34% of calls and showed that 39% of persons received care elsewhere on the same day, 35% received care within 3 days, and 26% decided not to seek medical care. A group of 1.0% sought care at other hospital EDs for minor complaints.

CONCLUSION

A subset of patients with nonemergency problems can be prospectively identified and triaged out of the ED without significant adverse outcomes provided there is community support for follow-up care.

Two-year outcome of social skills training and group psychotherapy for outpatients with schizophrenia

OBJECTIVE

The authors evaluated the effectiveness of behaviorally oriented social skills training and supportive group therapy for improving the social adjustment of schizophrenic patients living in the community and for protecting them against psychotic relapse.

METHOD

Eighty male outpatients with schizophrenia were stabilized with a low dose of fluphenazine decanoate (5 to 10 mg every 14 days), which was supplemented with oral fluphenazine (5 mg twice daily) or a placebo when they first met criteria for a prodromal period. (Half of the patients did so at some time during the study.) Patients were randomly assigned to receive either social skills training or supportive group therapy twice weekly for 6 months and then weekly for the next 18 months. Rates of psychotic exacerbation were monitored, as were scores on the Social Adjustment Scale II.

RESULTS

There were significant main effects favoring social skills training over supportive group therapy on two of the six Social Adjustment Scale II cluster totals examined (personal well-being and total) and significant interactions between psychosocial treatment and drug treatment for three items (external family, social and leisure activities, and total). In each case, these interactions indicated that the advantage of social skills training over supportive group therapy was greatest when it was combined with active drug supplementation. Social skills training did not significantly decrease the risk of psychotic exacerbation in the full group, but an advantage was observed (post hoc) among patients who received placebo supplementation.

CONCLUSIONS

These findings suggest that social skills training resulted in greater improvement in certain measures of social adjustment than supportive group therapy. The greatest improvement in social outcomes occurred when social skills training was combined with a pharmacological strategy of active drug supplementation at the time prodromal worsening of psychotic symptoms was first observed. However, these improvements were modest in absolute terms and confined to certain subgroups of patients.

HSP90 inhibition enhances cancer immunotherapy by upregulating interferon response genes

T-cell-based immunotherapies are promising treatments for cancer patients. Although durable responses can be achieved in some patients, many patients fail to respond to these therapies, underscoring the need for improvement with combination therapies. From a screen of 850 bioactive compounds, we identify HSP90 inhibitors as candidates for combination with immunotherapy. We show that inhibition of HSP90 with ganetespib enhances T-cell-mediated killing of patient-derived human melanoma cells by their autologous T cells in vitro and potentiates responses to anti-CTLA4 and anti-PD1 therapy in vivo. Mechanistic studies reveal that HSP90 inhibition results in upregulation of interferon response genes, which are essential for the enhanced killing of ganetespib treated melanoma cells by T cells. Taken together, these findings provide evidence that HSP90 inhibition can potentiate T-cell-mediated anti-tumor immune responses, and rationale to explore the combination of immunotherapy and HSP90 inhibitors.

Many patients fail to respond to T cell based immunotherapies. Here, the authors, through a high-throughput screening, identify HSP90 inhibitors as a class of preferred drugs for treatment combination with immunotherapy.

Microdifferentiation in a natural population of Drosophila melanogaster to alcohol in the environment

Strains of D. melanogaster derived from a vineyard population were more resistant to alcohol in the environment than strains from a population derived from an area removed from the vineyard. Within the vineyard population those strains most closely associated with alcohol in the environment in the cellar were more resistant than those collected outside the cellar. There was evidence of gene flow between the inside and outside cellar components of this population, but microdifferentiation had occurred within the cellar in spite of this. The adaptation appears to be independent of the ADH system and involves both additive and dominance genetic effects. D. simulans, a species not found in the cellar and susceptible to the presence of alcohol, showed no differentiation between vineyard and removed populations.

The genetic, molecular and phenotypic consequences of selection for insecticide resistance

Studies of insecticide resistance allow theories of the adaptive process to be tested where the selective agent, the insecticide, is unambiguously defined. Thus, the consequences of selection of phenotypic variation can be investigated in genetic, biochemical, molecular, population biological and, most recently, developmental contexts. Are the options limited biochemically and molecularly? Is the genetic mechanism monogenic or polygenic, general or population/species specific? Are fitness and developmental patterns associated? These questions of general evolutionary significance can be considered with experimental approaches to determine how insecticide resistance evolves.

Selective serotonin reuptake inhibitors (SSRIs) for depressive disorders in children and adolescents

BACKGROUND

Depressive disorders are common in young people and are associated with significant negative impacts. Selective serotonin reuptake inhibitors (SSRIs) are often used, however, evidence of their effectiveness in children and adolescents is not clear. Furthermore, there have been warnings against their use in this population due to concerns about increased risk of suicidal ideation and behaviour.

OBJECTIVES

To determine the efficacy and adverse outcomes, including definitive suicidal behaviour and suicidal ideation, of SSRIs compared to placebo in the treatment of depressive disorders in children and adolescents.

SEARCH STRATEGY

We searched the CCDAN Trials Register, MEDLINE, PSYCHINFO and CENTRAL. Reference lists were checked, letters were sent to key researchers and internet databases searched.

SELECTION CRITERIA

We included published and unpublished randomised controlled trials.

DATA COLLECTION AND ANALYSIS

Two or three review authors selected the trials, assessed the quality and extracted trial and outcome data. We used a fixed-effect meta-analysis. The relative risk was used to summarise dichotomous outcomes and the mean difference to summarise continuous measures.

MAIN RESULTS

Twelve trials were eligible for inclusion, with ten providing usable data. At 8-12 weeks, there was evidence that children and adolescents 'responded' to treatment with SSRIs (RR 1.28, 95% CI 1.17 to 1.41). There was also evidence of an increased risk of suicidal ideation and behaviour for those prescribed SSRIs (RR 1.80, 95% CI 1.19 to 2.72). Fluoxetine was the only SSRI where there was consistent evidence from three trials that it was effective in reducing depression symptoms in both children and adolescents (CDRS-R treatment effect -5.63, 95% CI -7.38 to -3.88), and 'response' to treatment (RR 1.86, 95% CI 1.49 to 2.32). Where rates of adverse events were reported, this was higher for those prescribed SSRIs.

AUTHORS' CONCLUSIONS

Caution is required to interpret the results. First, there were methodological issues, including high attrition, issues regarding measurement instruments and clinical usefulness of outcomes, often variously defined across trials. Second, patients seen in clinical practice are likely to be more unwell, and at greater risk of suicide, compared to those in the trials, and it is unclear how this group would respond to SSRIs. This needs to be considered, along with the evidence of an increased risk of suicide related outcomes in those treated with SSRIs. It is unclear what the effect of SSRIs is on suicide completion. While untreated depression is associated with the risk of completed suicide and impacts on functioning, it is unclear whether SSRIs would modify this risk in a clinically meaningful way.

Obstructive sleep apnoea and perioperative complications in bariatric patients

BACKGROUND

The objective of this study was to determine the relationship between perioperative complications and the severity of obstructive sleep apnoea (OSA) in patients undergoing bariatric surgery who had undergone preoperative polysomnography (PSG).

METHODS

The records of 797 patients, age >18 yr, who underwent bariatric operations (442 open and 355 laparoscopic procedures) at Mayo Clinic and were assessed before operation by PSG, were reviewed retrospectively. OSA was quantified using the apnoea-hypopnoea index (AHI) as none (≤ 4), mild (5-15), moderate (16-30), and severe (≥ 31). Pulmonary, surgical, and 'other' complications within the first 30 postoperative days were analysed according to OSA severity. Logistic regression was used to assess the multivariable association of OSA, age, sex, BMI, and surgical approach with postoperative complications.

RESULTS

Most patients with OSA (93%) received perioperative positive airway pressure therapy, and all patients were closely monitored after operation with pulse oximetry on either regular nursing floors or in intensive or intermediate care units. At least one postoperative complication occurred in 259 patients (33%). In a multivariable model, the overall complication rate was increased with open procedures compared with laparoscopic. In addition, increased BMI and age were associated with increased likelihood of pulmonary and other complications. Complication rates were not associated with OSA severity.

CONCLUSIONS

In obese patients evaluated before operation by PSG before bariatric surgery and managed accordingly, the severity of OSA, as assessed by the AHI, was not associated with the rate of perioperative complications. These results cannot determine whether unrecognized and untreated OSA increases risk.

Lenvatinib plus pembrolizumab versus sunitinib as first-line treatment of patients with advanced renal cell carcinoma (CLEAR): extended follow-up from the phase 3, randomised, open-label study

BACKGROUND

In the primary analysis of the CLEAR study, lenvatinib plus pembrolizumab significantly improved progression-free survival and overall survival versus sunitinib in patients with advanced renal cell carcinoma (data cutoff Aug 28, 2020). We aimed to assess overall survival based on 7 months of additional follow-up.

METHODS

This is a protocol-prespecified updated overall survival analysis (data cutoff March 31, 2021) of the open-label, phase 3, randomised CLEAR trial. Patients with clear-cell advanced renal cell carcinoma who had not received any systemic anticancer therapy for renal cell carcinoma, including anti-vascular endothelial growth factor therapy, or any systemic investigational anticancer drug, were eligible for inclusion from 200 sites (hospitals and cancer centres) across 20 countries. Patients were randomly assigned (1:1:1) to receive lenvatinib (20 mg per day orally in 21-day cycles) plus pembrolizumab (200 mg intravenously every 21 days; lenvatinib plus pembrolizumab group), lenvatinib (18 mg per day orally) plus everolimus (5 mg per day orally; lenvatinib plus everolimus group [not reported in this updated analysis]) in 21-day cycles, or sunitinib (50 mg per day orally, 4 weeks on and 2 weeks off; sunitinib group). Eligible patients were at least 18 years old with a Karnofsky performance status of 70 or higher. A computer-generated randomisation scheme was used, and stratification factors were geographical region and Memorial Sloan Kettering Cancer Center prognostic groups. The primary endpoint was progression-free survival assessed by independent imaging review according to Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1). In this Article, extended follow-up analyses for progression-free survival and protocol-specified updated overall survival data are reported for the intention-to-treat population. No safety analyses were done at this follow-up. This study is closed to new participants and is registered with ClinicalTrials.gov, NCT02811861.

FINDINGS

Between Oct 13, 2016, and July 24, 2019, 1417 patients were screened for inclusion in the CLEAR trial, of whom 1069 (75%; 273 [26%] female, 796 [74%] male; median age 62 years [IQR 55-69]) were randomly assigned: 355 (33%) patients (255 [72%] male and 100 [28%] female) to the lenvatinib plus pembrolizumab group, 357 (33%) patients (275 [77%] male and 82 [23%] female) to the sunitinib group, and 357 (33%) patients to the lenvatinib plus everolimus group (not reported in this updated analysis). Median follow-up for progression-free survival was 27·8 months (IQR 20·3-33·8) in the lenvatinib plus pembrolizumab group and 19·4 months (5·5-32·5) in the sunitinib group. Median progression-free survival was 23·3 months (95% CI 20·8-27·7) in the lenvatinib plus pembrolizumab group and 9·2 months (6·0-11·0) in the sunitinib group (stratified hazard ratio [HR] 0·42 [95% CI 0·34-0·52]). Median overall survival follow-up was 33·7 months (IQR 27·4-36·9) in the lenvatinib plus pembrolizumab group and 33·4 months (26·7-36·8) in the sunitinib group. Overall survival was improved with lenvatinib plus pembrolizumab (median not reached [95% CI 41·5-not estimable]) versus sunitinib (median not reached [38·4-not estimable]; HR 0·72 [95% CI 0·55-0·93]).

INTERPRETATION

Efficacy benefits of lenvatinib plus pembrolizumab over sunitinib were durable and clinically meaningful with extended follow-up. These results support the use of lenvatinib plus pembrolizumab as a first-line therapy for patients with advanced renal cell carcinoma.

FUNDING

Eisai and Merck Sharp & Dohme.

Progression of dopaminergic dysfunction in a LRRK2 kindred: a multitracer PET study

OBJECTIVE

Little is known about the progression of dopaminergic dysfunction in LRRK2-associated Parkinson disease (PD). We sought to characterize the neurochemical progression with multitracer PET in asymptomatic members of parkinsonian kindred (family D, Western Nebraska) carrying LRRK2 (R1441C) mutation.

METHOD

Thirteen family D subjects underwent PET scans of presynaptic dopaminergic integrity and five subjects were rescanned 2 to 3 years later.

RESULTS

In subjects 8, 9 (mutation carriers), and 13 (genealogically at risk subject), there was a decline in PET markers over the course of the study that was significantly greater than the expected rate of decline in healthy controls. Reduced dopamine transporter binding was the earliest indication of subclinical dopaminergic dysfunction and progression to clinical disease was generally associated with the emergence of abnormal fluorodopa uptake.

CONCLUSION

PET study of presymptomatic members of our LRRK2 kindred revealed dopaminergic dysfunction that progressed over time. This represents an ideal group to study the natural history of early disease and the potential effects of neuroprotective interventions.

Lifelong farm exposure may strongly reduce the risk of asthma in adults

BACKGROUND

Farm exposures may protect against childhood asthma, hay fever and eczema. Whether farm exposures also confer protection in adult farmers remains unclear. Moreover, little is known about the role of timing of exposure. We assessed the effects of current and childhood farm exposures on asthma, hay fever and eczema in farmers and a rural nonfarming control population.

METHODS

We conducted a cross-sectional questionnaire survey in 2509 farming families (response rate 78%) and 1001 nonfarming families (response rate 67%), which included 4288 farmers and 1328 nonfarmers.

RESULTS

Farmers were less likely to have asthma symptoms, hay fever and eczema; no significant differences were observed among dairy, sheep and beef, and horticulture farmers. A combination of current and childhood exposure was more strongly associated with shortness of breath (OR 0.50, CL 0.39-0.66), wheeze (OR 0.60, CL 0.49-0.73), asthma medication (OR 0.48, CL 0.37-0.63); and asthma ever (OR 0.56, CL 0.46-0.68) than current exposure alone (OR 0.63, CL 0.47-0.84; OR 0.80, CL 0.65-0.99; OR 0.68, CL 0.51-0.9; OR 0.69, CL 0.56-0.85 respectively) or childhood exposure alone (OR 0.97, CL0.65-1.44; OR 1.01, CL 0.75-1.34; OR 0.78, CL 0.51-1.19; OR 0.87, CL 0.63-1.19 respectively). Moreover, the combined number of years of farm exposure in childhood and adulthood showed a dose-dependent inverse association with symptom prevalence.

CONCLUSIONS

Although both current and childhood farm exposures may play a role in the observed low prevalence of asthma symptoms in adult farmers, continued long-term exposure may be required to maintain optimal protection.

The efficacy of endovascular stenting in the treatment of supraclinoid internal carotid artery blister aneurysms using a stent-in-stent technique

BACKGROUND AND PURPOSE

Blister aneurysms of the supraclinoid ICA represent a rare but well-documented cause of subarachnoid hemorrhage. These aneurysms are difficult to detect, and their surgical treatment is challenging, with high morbidity and mortality rates. The reports currently in the literature that describe the surgical and endovascular treatment of these aneurysms offer no clear consensus on the optimal treatment. We describe a staged endovascular treatment entailing stenting using a stent-in-stent technique, as well as planned but delayed embolization as the aneurysm increases in size to allow the introduction of coils.

MATERIALS AND METHODS

We performed a retrospective review of all cerebral angiograms performed at our institution over an 8-month period for evaluation of subarachnoid hemorrhage, identifying 6 ICA blister aneurysms.

RESULTS

All 6 blister aneurysms were located in the supraclinoid ICA. The stent-in-stent technique was used for the initial treatment of all patients. Three patients had no residual or recurrent aneurysm following initial treatment. Three patients required retreatment with coils after continued growth of the aneurysm, identified on follow-up angiography. Five patients had good recovery (average mRS score of 1), and 1 patient had poor neurologic recovery (mRS score of 3) due to a large hemorrhagic infarction.

CONCLUSIONS

Our case series suggests that staged endovascular treatment entailing the use of a stent-in-stent technique, augmented with subsequent coil embolization as necessary for progressive disease, is a viable endovascular option for treating ruptured supraclinoid blister aneurysms, allowing for parent artery preservation.

The RNA-binding Protein MEX3B Mediates Resistance to Cancer Immunotherapy by Downregulating HLA-A Expression

Purpose: Cancer immunotherapy has shown promising clinical outcomes in many patients. However, some patients still fail to respond, and new strategies are needed to overcome resistance. The purpose of this study was to identify novel genes and understand the mechanisms that confer resistance to cancer immunotherapy.Experimental Design: To identify genes mediating resistance to T-cell killing, we performed an open reading frame (ORF) screen of a kinome library to study whether overexpression of a gene in patient-derived melanoma cells could inhibit their susceptibility to killing by autologous tumor-infiltrating lymphocytes (TIL).Results: The RNA-binding protein MEX3B was identified as a top candidate that decreased the susceptibility of melanoma cells to killing by TILs. Further analyses of anti-PD-1-treated melanoma patient tumor samples suggested that higher MEX3B expression is associated with resistance to PD-1 blockade. In addition, significantly decreased levels of IFNγ were secreted from TILs incubated with MEX3B-overexpressing tumor cells. Interestingly, this phenotype was rescued upon overexpression of exogenous HLA-A2. Consistent with this, we observed decreased HLA-A expression in MEX3B-overexpressing tumor cells. Finally, luciferase reporter assays and RNA-binding protein immunoprecipitation assays suggest that this is due to MEX3B binding to the 3' untranslated region (UTR) of HLA-A to destabilize the mRNA.Conclusions: MEX3B mediates resistance to cancer immunotherapy by binding to the 3' UTR of HLA-A to destabilize the HLA-A mRNA and thus downregulate HLA-A expression on the surface of tumor cells, thereby making the tumor cells unable to be recognized and killed by T cells. Clin Cancer Res; 24(14); 3366-76. ©2018 AACRSee related commentary by Kalbasi and Ribas, p. 3239.

Scalloped wings is the Lucilia cuprina Notch homologue and a candidate for the modifier of fitness and asymmetry of diazinon resistance

The Scalloped wings (Scl) gene of the Australian sheep blowfly, Lucilia cuprina, is shown to be the homologue of the Drosophila melanogaster Notch gene by comparison at the DNA sequence and genetic levels. A L. cuprina genomic fragment, which shows strong identity with the Notch (N) gene at the molecular level, hybridizes to the location of the Scl gene on polytene chromosomes. The two genes are functionally homologous; the dominant and recessive Notch-like phenotypes produced by mutations in the Scl gene allow these alleles to be classed as N-like or Abruptex-like. The Scl gene is under investigation as a candidate for the fitness and asymmetry Modifier (M) of diazinon resistance. We show that M affects the penetrance of wing and bristle phenotypes associated with two Scl alleles in a manner consistent with the M being an allele of Scl. In addition, we report a phenotypic interaction between the diazinon-resistance mutation, Rop-1, and the same alleles of Scl. We propose that the product of Rop-1, an esterase, may be involved in cell adhesion in developmental processes involving the Scl gene product.

Predicting insecticide resistance: mutagenesis, selection and response

Strategies to manage resistance to a particular insecticide have usually been devised after resistance has evolved. If it were possible to predict likely resistance mechanisms to novel insecticides before they evolved in the field, it might be feasible to have programmes that manage susceptibility. With this approach in mind, single-gene variants of the Australian sheep blowfly, Lucilia cuprina, resistant to dieldrin, diazinon and malathion, were selected in the laboratory after mutagenesis of susceptible strains. The genetic and molecular bases of resistance in these variants were identical to those that had previously evolved in natural populations. Given this predictive capacity for known resistances, the approach was extended to anticipate possible mechanisms of resistance to cyromazine, an insecticide to which L. cuprina populations remain susceptible after almost 20 years of exposure. Analysis of the laboratory-generated resistant variants provides an explanation for this observation. The variants show low levels of resistance and a selective advantage over susceptibles for only a limited concentration range. These results are discussed in the context of the choice of insecticides for control purposes and of delivery strategies to minimize the evolution of resistance.