Association of MAPT Subhaplotypes With Risk of Progressive Supranuclear Palsy and Severity of Tau Pathology

Importance

The association between the microtubule-associated protein tau (MAPT) H1 haplotype and the risk of progressive supranuclear palsy (PSP) has been well documented. However, the specific H1 subhaplotypes that drive the association have not been evaluated in large studies, nor have they been studied in relation to neuropathologic severity of disease.

Objective

To comprehensively evaluate the associations of MAPT haplotypes with the risk of PSP and the severity of tau pathology using a large series of neuropathologically confirmed PSP cases.

Design, Setting, and Participants

A case-control study was used to investigate the associations between MAPT haplotypes and the risk of PSP, and a case series was conducted for examination of associations of MAPT haplotypes with the severity of tau pathology. All 802 neuropathologically confirmed PSP cases were obtained from a neurodegenerative disorders brain bank between January 1, 1998, and December 31, 2013, and 1312 clinical controls were obtained from the neurology department of the Mayo Clinic. Statistical analysis was performed from February 17 to December 12, 2018.

Main Outcomes and Measures

Presence of PSP in case-control analysis and semiquantitative tau pathology scores for neurofibrillary tangles, neuropil threads, tufted astrocytes, and oligodendroglial coiled bodies in PSP cases.

Results

For 802 patients with PSP (376 women and 426 men), the median age at death was 75 years (range, 52-98 years). For 1312 controls (701 women and 611 men), the median age at blood collection was 69 years (range, 45-92 years). After adjustment for multiple testing, known associations with risk of PSP were observed for the H2 and H1c haplotypes. Novel associations with PSP were observed for 3 H1 subhaplotypes, including H1d (odds ratio, 1.86; 95% CI, 1.43-2.42; P = 2 × 10-6), H1g (odds ratio, 3.64; 95% CI, 2.04-6.50; P = 2 × 10-6), and H1o (odds ratio, 2.60; 95% CI, 1.63-4.16; P = 2 × 10-5). Although not significant after multiple testing adjustment, 3 of these PSP risk haplotypes (H2, H1c, and H1d) were also nominally associated with measures of severity of tau pathology in PSP cases. Nominally significant associations with severity of tau pathology were also noted for the H1e and H1q haplotypes.

Conclusions and Relevance

This study has identified novel associations with risk of PSP for 3 MAPT H1 subhaplotypes. In addition, potential weaker associations between several haplotypes (including several PSP risk haplotypes) and severity of tau pathology were observed. These findings expand the current understanding of the role of MAPT haplotypic variation in susceptibility to and neuropathologic severity of PSP.

Efficacy of immune checkpoint inhibitors in older patients with non-small cell lung cancer: Real-world data from multicentric cohorts in Canada and France

BACKGROUND

Age-related immune remodelling is thought to be associated with resistance to immune checkpoint inhibitors (ICIs) in cancer. Patients older than 70 years, representing >50% of the population with non-small cell lung cancer (NSCLC) according to SEER database, are underrepresented in clinical trials exploring ICIs. The objective of this study was to determine if patients with NSCLC older than ≥70 years had inferior clinical outcomes with ICIs.

METHODS

We conducted a retrospective analysis of 381 patients treated with anti-PD-(L)1 ICI for advanced NSCLC at the Dijon Cancer Center (n = 177), University of Montreal Hospital (n = 106) and Quebec Heart and Lung Institute (n = 98). Age was considered as a categorical variable. Patients' baseline characteristics were compared using the Chi-squared test. Survival curves were estimated by the Kaplan-Meier method and compared with the Log-rank test in a univariate analysis. Multivariate cox regression model was used to determine hazard ratios and 95% confidence intervals for progression-free survival (PFS) and overall survival (OS) between the groups, adjusting for other clinicopathologic features.

RESULTS

Among 381 patients included, 335 (88%) received ICI after platinum chemotherapy. The median age was 66 (range 37-89) and 33% were older than 70 years of age. Considering age as a categorical variable, differences in age were not associated with PFS or OS. Subgroup analysis and multivariate cox regression did not reveal significant interaction of age with outcomes. ECOG performance status was the only significant factor in the three cohorts.

CONCLUSIONS

Unlike previously described in the era of chemotherapy, age was not associated with outcomes in NSCLC patients treated with ICI.

DNA methylation stability in fish spermatozoa upon external constraint: Impact of fish hormonal stimulation and sperm cryopreservation

Highly differentiated mature spermatozoa carry not only genetic but also epigenetic information that is to be transmitted to the embryo. DNA methylation is one epigenetic actor associated with sperm nucleus compaction, gene silencing, and prepatterning of embryonic gene expression. Therefore, the stability of this mark toward reproductive biotechnologies is a major issue in animal production. The present work explored the impact of hormonal induction of spermiation and sperm cryopreservation in two cyprinids, the goldfish (Carassius auratus) and the zebrafish (Danio rerio), using LUminometric Methylation Assay (LUMA). We showed that while goldfish hormonal treatment did increase sperm production, it did not alter global DNA methylation of spermatozoa. Different sperm samples repeatedly collected from the same males for 2 months also showed the same global DNA methylation level. Similarly, global DNA methylation was not affected after cryopreservation of goldfish spermatozoa with methanol, whereas less efficient cryoprotectants (dimethylsulfoxide and 1,2-propanediol) decreased DNA methylation. In contrast, cryopreservation of zebrafish spermatozoa with methanol induced a slight, but significant, increase in global DNA methylation. In the less compact nuclei, that is, goldfish fin somatic cells, cryopreservation did not change global DNA methylation regardless of the choice of cryoprotectant. To conclude, global DNA methylation is a robust parameter with respect to biotechnologies such as hormonal induction of spermiation and sperm cryopreservation, but it can be altered when the best sperm manipulation conditions are not met.

Real-world health utility scores and toxicities to tyrosine kinase inhibitors in epidermal growth factor receptor mutated advanced non-small cell lung cancer

BACKGROUND

As the treatment landscape in patients with non-small cell lung cancer (NSCLC) harboring mutations in the epidermal growth factor receptor (EGFRm) continues to evolve, real-world health utility scores (HUS) become increasingly important for economic analyses.

METHODS

In an observational cohort study, questionnaires were completed in EGFRm NSCLC outpatients, to include demographics, EQ-5D-based HUS and patient-reported toxicity and symptoms. Clinical and radiologic characteristics together with outcomes were extracted from chart review. The impact of health states, treatment type, toxicities, and clinical variables on HUS were evaluated.

RESULTS

Between 2014 and 2018, a total of 260 patients completed 994 encounters. Across treatment groups, patients with disease progression had lower HUS compared to controlled disease (0.771 vs 0.803; P = .01). Patients predominantly received gefitinib as the first-line EGFR tyrosine kinase inhibitor (TKI) (n = 157, mean-HUS = 0.798), whereas osimertinib (n = 62, mean-HUS = 0.806) and chemotherapy (n = 38, mean-HUS = 0.721) were more likely used in subsequent treatment lines. In longitudinal analysis, TKIs retained high HUS (>0.78) compared to chemotherapy (HUS < 0.74). There were no differences between the frequency or severity of toxicity scores in patients receiving gefitinib compared to osimertinib; however, TKI therapy resulted in fewer toxicities than chemotherapy (P < .05), with the exception of worse diarrhea and skin rash (P < .001). Severity in toxicities inversely correlated with HUS (P < .001). Clinico-demographic factors significantly affecting HUS included age, Eastern Cooperative Oncology Group Performance Score (ECOG PS), disease state, treatment group, and metastatic burden.

CONCLUSIONS

In a real-world EGFRm population, patients treated with gefitinib or osimertinib had similar HUS and toxicities, scores which were superior to chemotherapy. Health utility scores inversely correlated with patient-reported toxicity scores. In the era of targeted therapies, future economic analyses should incorporate real-world HUS.

Anaplastic lymphoma kinase 5A4 immunohistochemistry as a diagnostic assay in lung cancer: A Canadian reference testing center's results in population-based reflex testing

BACKGROUND

The presence of anaplastic lymphoma kinase (ALK) rearrangement predicts response to ALK tyrosine kinase inhibitor (TKI) therapy. Fluorescence in situ hybridization (FISH) was the initial reference standard to detect ALK rearrangement, but immunohistochemistry (IHC) using D5F3 has gained acceptance as an alternative diagnostic method. ALK IHC assays using other ALK antibodies have also been used as screening methods, but data supporting their utility as diagnostic tests have not been widely reported.

METHODS

Data from reflexive clinical ALK IHC test using the 5A4 clone concurrent with epidermal growth factor receptor (EGFR) mutation testing were analyzed. ALK IHC results were reported as negative (-), equivocal, or positive (+), with equivocal or positive staining validated by FISH break-apart probe testing. Treatment outcomes were reviewed for ALK IHC+ patients.

RESULTS

Between 2012 and 2015, 146 (2.5%) cases were reported as ALK IHC+, 188 (3.2%) were reported as equivocal, and 5624 (94.4%) were reported as ALK IHC-. Of the ALK IHC+ cases, 131/143(91.6%) were ALK FISH+. Excluding 6 cases in which FISH was inconclusive or not performed, the positive predictive value was 95.6%, and the negative predictive value was 100%. Most specimens (n = 5352 [89.6%]) were also successfully tested for EGFR. Clinical responses to ALK TKIs were noted in 49 ALK IHC+ patients, with a median progression-free survival of 9.9 months.

CONCLUSIONS

ALK 5A4 IHC can serve as a robust diagnostic test for ALK-rearranged lung cancer and is associated with treatment response and survival. Optimized tissue allocation resulted in high success rates of combined reflex EGFR and ALK testing.

Embryonic Exposure to Bisphenol A Impairs Primordial Germ Cell Migration without Jeopardizing Male Breeding Capacity

A large amount of chemicals are released to the environment each year. Among them, bisphenol A (BPA) is of utmost concern since it interferes with the reproductive system of wild organisms due to its capacity to bind to hormone receptors. Additionally, BPA epigenotoxic activity is known to affect basic processes during embryonic life. However, its effects on primordial germ cells (PGCs) proliferation and migration, both mechanisms being crucial for gametogenesis, remain unknown. To investigate the effects of BPA on PGCs migration and eventual testicle development, zebrafish embryos were exposed to 100, 2000 and 4000 µg/L BPA during the first 24 h of development. Vasa immunostaining of PGCs revealed that exposure to 2000 and 4000 µg/L BPA impaired their migration to the genital ridge. Two pivotal genes of PGCs migration (cxcr4b and sdf1a) were highly dysregulated in embryos exposed to these doses, whereas DNA methylation and epigenetic marks in PGCs and their surrounding somatic cells were not altered. Once embryos reached adulthood, the morphometric study of their gonads revealed that, despite the reduced number of PGCs which colonized the genital ridges, normal testicles were developed. Although H3K9ac decreased in the sperm from treated fishes, it did not affect the progeny development.

A newly developed cloning technique in sturgeons; an important step towards recovering endangered species

Several steps of sturgeon somatic cell nuclear transfer (SCNT) have been recently established, but improvements are needed to make it a feasible tool to preserve the natural populations of this group of endangered species. The donor cell position inside the recipient egg seems to be crucial for its reprogramming; therefore by injecting multiple donor somatic cells instead of a single cell with a single manipulation, we increased the potential for embryo development. Using the Russian sturgeon Acipenser gueldenstaedtii as a multiple cell donor and sterlet Acipenser ruthenus as the non-enucleated egg recipient, we obtained higher proportion of eggs developing into embryos than previously reported with single-SCNT. Molecular data showed the production of a specimen (0.8%) contained only the donor genome with no contribution from the recipient, while two specimens (1.6%) showed both recipient and donor genome. These findings are the first report of donor DNA integration into a sturgeon embryo after interspecific cloning. In all, we provide evidence that cloning with the multiple donor somatic cells can be feasible in the future. Despite the fact that the sturgeon cloning faces limitations, to date it is the most promising technique for their preservation.

Association of MAPT H1 subhaplotypes with neuropathology of lewy body disease

BACKGROUND

Genetic variation at the microtubule-associated protein tau locus is associated with clinical parkinsonism. However, it is unclear as to whether microtubule-associated protein tau H1 subhaplotypes are associated with the burden of neuropathological features of Lewy body disease.

OBJECTIVES

To evaluate associations of microtubule-associated protein tau haplotypes with severity of Lewy body pathology and markers of SN neuronal loss in Lewy body disease cases.

METHODS

Five hundred eighty-five autopsy-confirmed Lewy body disease cases were included. Six microtubule-associated protein tau variants (rs1467967, rs242557, rs3785883, rs2471738, rs8070723, and rs7521) were genotyped to define common microtubule-associated protein tau haplotypes. Lewy body counts were measured in five cortical regions. Ventrolateral and medial SN neuronal loss were assessed semiquantitatively. Nigrostriatal dopaminergic degeneration was quantified by image analysis of tyrosine hydroxylase immunoreactivity in the dorsolateral and ventromedial putamen.

RESULTS

The common microtubule-associated protein tau H2 haplotype did not show a strong effect on pathological burden in Lewy body disease. The rare H1j haplotype (1.3%) was significantly associated with a lower dorsolateral putaminal tyrosine hydroxylase immunoreactivity (and therefore greater dopaminergic degeneration) compared to other microtubule-associated protein tau haplotypes (P = 0.0016). Microtubule-associated protein tau H1j was also nominally (P ≤ 0.05) associated with a lower ventromedial putaminal tyrosine hydroxylase immunoreactivity (P = 0.010), but this did not survive multiple testing correction. Other nominally significant associations between microtubule-associated protein tau H1 subhaplotypes and neuropathological outcomes were observed.

CONCLUSIONS

A rare microtubule-associated protein tau H1 subhaplotype (H1j) may be associated with more severe putaminal dopaminergic degeneration in Lewy body disease cases. Microtubule-associated protein tau H1j has been associated previously with an increased risk of PD, and therefore our exploratory findings provide insight into the mechanism by which H1j modulates PD risk. © 2019 International Parkinson and Movement Disorder Society.

The Impact of Brain Metastases and Associated Neurocognitive Aspects on Health Utility Scores in EGFR Mutated and ALK Rearranged NSCLC: A Real World Evidence Analysis

BACKGROUND

In lung cancer, brain metastases (BM) and their treatment are associated with high economic burden and inferior health-related quality of life. In the era of targeted therapy, real world evidence through health utility scores (HUS) is critical for economic analyses.

MATERIALS AND METHODS

In a prospective observational cohort study (2014-2016), outpatients with stage IV lung cancer completed demographic and EQ-5D-3L surveys (to derive HUS). Health states and clinicopathologic variables were obtained from chart abstraction. Patients were categorized by the presence or absence of BM; regression analyses identified factors that were associated with HUS. A subset of patients prospectively completed neurocognitive function (NCF) tests and/or the FACT-brain (FACT-Br) questionnaire, which were then correlated with HUS (Spearman coefficients; regression analyses).

RESULTS

Of 519 patients with 1,686 EQ-5D-3L-derived HUS, 94 (18%) completed NCF tests and 107 (21%) completed FACT-Br; 301 (58%) never developed BM, 24 (5%) developed first BM during study period, and 194 (37%) had BM at study entry. The sample was enriched (46%) for EGFR mutations (EGFRm) and ALK-rearrangements (ALKr). There were no HUS differences by BM status overall and in subsets by demographics. In multivariable analyses, superior HUS was associated with having EGFRm/ALKr (p < .0001), no prior radiation for extracranial disease (p < .001), and both intracranial (p = .002) and extracranial disease control (p < .01). HUS correlated with multiple elements of the FACT-Br and tests of NCF.

CONCLUSION

Having BM in lung cancer is not associated with inferior HUS in a population enriched for EGFRm and ALKr. Patients exhibiting disease control and those with oncogene-addicted tumors have superior HUS.

IMPLICATIONS FOR PRACTICE

In the setting of EGFR mutations or ALK rearrangement non-small cell lung cancer (NSCLC), a diagnosis of brain metastases no longer consigns the patient to an inferior health state suggesting that new economic analyses in NSCLC are needed in the era of targeted therapies. Additionally, the EQ-5D questionnaire is associated with measures of health-related quality of life and neurocognitive scores suggesting this tool should be further explored in prospective clinical studies.

Nuclear import of Xenopus egg extract components into cultured cells for reprogramming purposes: a case study on goldfish fin cells

Reprogramming of cultured cells using Xenopus egg extract involves controlling four major steps: plasma membrane permeabilization, egg factors import into the nucleus, membrane resealing, and cell proliferation. Using propidium iodide to assess plasma membrane permeability, we established that 90% of the cultured fin cells were permeabilized by digitonin without any cell losses. We showed that egg extract at metaphase II stage was essential to maintain nuclear import function in the permeabilized cells, as assessed with a fusion GFP protein carrying the nuclear import signal NLS. Moreover, the Xenopus-egg-specific Lamin B3 was detected in 87% of the cell nuclei, suggesting that other egg extract reprogramming factors of similar size could successfully enter the nucleus. Lamin B3 labelling was maintained in most cells recovered 24 h after membrane resealing with calcium, and cells successfully resumed cell cycle in culture. In contrast, permeabilized cells that were not treated with egg extract failed to proliferate in culture and died, implying that egg extract provided factor essential to the survival of those cells. To conclude, fish fin cells were successfully primed for treatment with reprogramming factors, and egg extract was shown to play a major role in their survival and recovery after permeabilization.

Correlation between composition, microstructure, and emission properties in Nd-doped Si-rich Si oxynitride films: investigation into the nature of the sensitizer

Rare earth (RE) ions doped in Si-based materials, compatible with Si technology, are promising compounds with regards to optical communication and energy conversion. In this article, we show the emission properties of Nd-doped Si-rich Si oxynitride (Nd-SRSON) films, and their dependence on the dangling bond density and the nature of the sensitizer. These films were prepared by reactive magnetron sputtering and post-annealing. The film composition, microstructure, and emission properties were investigated as a function of deposition parameters and annealing temperatures. Both Fourier transform infrared (FTIR) and ellipsometry spectroscopy measurements have confirmed that the sample composition (Si/N ratio) can be carefully tuned by varying the ratio of reactive nitrogen to argon in the sputtering plasma. Moreover, FTIR and x-ray photoelectron spectroscopy measurements demonstrate the existence of both nitrogen and oxygen dangling bonds (N· and O·) in as-deposited samples. These dangling bonds were passivated during annealing. Under non-resonant excitation at 488 nm, the films exhibit a significant photoluminescence (PL) signal from Nd³⁺ ions demonstrating the occurrence of an effective sensitization of Nd³⁺ ions in the host matrix. Both PL excitation and ellipsometry results (the energy band gap from new amorphous model) exclude the sensitization by an exciton with energy over the band gap, whereas the presence of Si agglomerates, at the atomic scale, have been identified as effective sensitizers towards Nd³⁺ ions. This work not only provides knowledge to optimize Si-based materials for favorable emission properties, but also, presents a universal methodology to investigate the nature of sensitizers for RE emitters. This allows one to find correlations between composition, microstructure, and emission properties.

18 Characterisation of early embryonic cellular defects after somatic cell nuclear transfer in fish

Cryopreservation of genetic resources is of major interest for the security of biodiversity and the sustainability of the agronomic industry. Cryopreservation of somatic cells is one means of preserving the genome of both parents, but regeneration of functional breeders requires the mastering of somatic cell NT (SCNT). In mammals, SCNT consists of injecting the somatic nuclei into enucleated recipient oocytes to obtain clones that bear the genome of the donor. Cloning in fish presents some advantages over cloning in mammals: oocytes are produced by the hundreds, and development is external. Moreover, embryonic genome activation takes place after 10 mitoses only. These features are favourable to a better understanding of cellular reprogramming of the somatic cell. Nonenucleated oocytes are often used for SCNT, which allows the production of 2n clones bearing only the donor genome when the maternal chromatin is spontaneously removed by an unknown mechanism (25% of cases). This ability can help us understand the fate of the maternal chromatin and the role of its surrounding factors on the cellular behaviour of the somatic cell during the first developmental steps of embryonic development: meiosis resumption (MR) and mitosis. In this study, fin somatic cells and mature oocytes were obtained from a 2-year-old goldfish (Carassius auratus). For SCNT, the whole fin cell was injected into the sperm entry site, and the oocyte was activated by water contact after 30min to begin the development. Somatic and maternal chromatin behaviour during MR and early mitosis were characterised by immunofluorescence (Hoechst/Vybrant labelling for chromatin identification and α-tubulin for spindle organisation). Variability in chromatin condensation was observed after the somatic cell injection before the activation. Clone analysis (n=16) revealed that some of them presented a condensed somatic nuclei (71%) and others presented a decondensed nuclei (29%). After activation, most clones underwent normal polar body extrusion of the maternal chromatin (66%, n=69/95 clones v. 96%, n=96/100 controls oocytes) without extrusion of a somatic polar body. Afterward, clones that presented a first symmetric division (n=14/35) were analysed at the 2-cells stage and compared with fertilized embryos (n=7). The maternal chromatin was observed as fragmented on the cleavage furrow (79%), where it cannot contribute to the development. Spindle defects were observed in 50% of clone cells (v. 0% in controls), such as multicentrosomal spindles, chromosome misalignment, abnormal segregation, and DNA fragmentation. To conclude, those clone (2n or 3n) defects are probably due to the chromatin condensation observed before activation. The fish oocyte volume did not allow the MR of the condensed somatic chromatin, and that may induce an abnormal anaphase and the following clone developmental defects.

Real-world benefit of nivolumab in a Canadian non-small-cell lung cancer cohort

Background

Nivolumab was the first immuno-oncology agent available for the treatment of lung cancer in Canada. In the present study, we evaluated the real-world benefit of nivolumab in Canadian patients with lung cancer.

Methods

Patients included in the cohort were identified from a registry of patients treated through expanded access to nivolumab before and after Health Canada approval. Demographics were collected from the application forms. Outcome data for the duration of treatment and survival were collected retrospectively.

Results

In contrast to the randomized clinical trial populations, our study cohort included patients who were older (median age: 66 years; range: 36-92 years) and who had an Eastern Cooperative Oncology Group performance status of 2 (8.9%). Despite the poorer-prognosis cohort, median overall survival was 12.0 months, which is comparable to the survival demonstrated in the randomized phase iii trials of nivolumab in lung cancer. Median time to treatment discontinuation was 3.45 months and was similar for all patient subgroups, including poorer-prognosis groups such as those with a performance status of 2, those 75 years of age and older, and those with brain metastases.

Conclusions

Nivolumab given in a real-world clinical setting was associated with results similar to those reported in the phase iii clinical trial setting.

Tumor-based gene expression biomarkers to predict survival following curative intent resection for stage I lung adenocarcinoma

Background

Prognostic biomarkers are needed in clinical setting to predict outcome after resection for early-stage lung adenocarcinoma. The goal of this study is to validate tumor-based single-gene expression biomarkers with demonstrated prognostic value in order to move them along the clinical translation pipeline.

Methods

Prognostic genes were selected from the literature and the best candidates measured by quantitative real-time polymerase chain reaction (qPCR) in tumors of 233 patients with stage I adenocarcinoma. Significant prognostic genes were then validated in an independent set of 210 patients matching the first set in terms of histology, stage, and clinical data.

Results

Eleven genes with demonstrated prognostic value were selected from the literature. Complementary analyses in public databases and our own microarray dataset led to the investigation of six genes associated with good (BTG2, SELENBP1 and NFIB) or poor outcome (RRM1, EZH2 and FOXM1). In the first set of patients, EZH2 and RRM1 were significantly associated with better survival on top of age, sex and pathological stage (EZH2 p = 3.2e-02, RRM1 p = 5.9e-04). The prognostic values of EZH2 and RRM1 were not replicated in the second set of patients. A trend was observed for both genes in the joint analyses (n = 443) with higher expression associated with worse outcome.

Conclusion

Adenocarcinoma-specific mRNA expression levels of EZH2 and RRM1 are associated with poor post-surgical survival in the first set of patients, but not replicated in a clinically and pathologically matched independent validation set. This study highlights challenges associated with clinical translation of prognostic biomarkers.

PCNT point mutations and familial intracranial aneurysms

OBJECTIVE

To identify novel genes involved in the etiology of intracranial aneurysms (IAs) or subarachnoid hemorrhages (SAHs) using whole-exome sequencing.

METHODS

We performed whole-exome sequencing in 13 individuals from 3 families with an autosomal dominant IA/SAH inheritance pattern to look for candidate genes for disease. In addition, we sequenced PCNT exon 38 in a further 161 idiopathic patients with IA/SAH to find additional carriers of potential pathogenic variants.

RESULTS

We identified 2 different variants in exon 38 from the PCNT gene shared between affected members from 2 different families with either IA or SAH (p.R2728C and p.V2811L). One hundred sixty-four samples with either SAH or IA were Sanger sequenced for the PCNT exon 38. Five additional missense mutations were identified. We also found a second p.V2811L carrier in a family with a history of neurovascular diseases.

CONCLUSION

The PCNT gene encodes a protein that is involved in the process of microtubule nucleation and organization in interphase and mitosis. Biallelic loss-of-function mutations in PCNT cause a form of primordial dwarfism (microcephalic osteodysplastic primordial dwarfism type II), and ≈50% of these patients will develop neurovascular abnormalities, including IAs and SAHs. In addition, a complete Pcnt knockout mouse model (Pcnt ^-/-) published previously showed general vascular abnormalities, including intracranial hemorrhage. The variants in our families lie in the highly conserved PCNT protein-protein interaction domain, making PCNT a highly plausible candidate gene in cerebrovascular disease.

Association study between multiple system atrophy and TREM2 p.R47H

Objective

The triggering receptor expressed on myeloid cells 2 (TREM2) p.R47H substitution (rs75932628) is a risk factor for Alzheimer disease (AD) but has not been well studied in relation to the risk of multiple system atrophy (MSA); the aim of this study was to evaluate the association between the TREM2 p.R47H variant and the risk of MSA.

Methods

A total of 168 patients with pathologically confirmed MSA, 89 patients with clinically diagnosed MSA, and 1,695 controls were included. TREM2 p.R47H was genotyped and assessed for association with MSA. Positive results in the Taqman genotyping assay were confirmed by Sanger sequencing. The primary comparison involved patients with pathologically confirmed MSA and controls due to the definitive MSA diagnosis in the pathologically confirmed series.

Results

We identified TREM2 p.R47H in 3 patients with pathologically confirmed MSA (1.79%), 1 patient with clinically diagnosed MSA (1.12%), and 7 controls (0.41%). Minimal AD pathology was observed for the pathologically confirmed MSA p.R47H carriers. For the primary comparison of patients with pathologically confirmed MSA and controls, risk of disease was significantly higher for p.R47H carriers (odds ratio [OR]: 4.39, p = 0.033). When supplementing the 168 pathologically confirmed patients with the 89 clinically diagnosed and examining the combined MSA series, the association with TREM2 p.R47H remained significant (OR: 3.81, p = 0.034).

Conclusions

Our preliminary results suggest that the TREM2 p.R47H substitution may be a risk factor for MSA, implying a link to neuroinflammatory processes, especially microglial activation. Validation of this finding will be important, given our relatively small sample size; meta-analytic approaches will be needed to better define the role of this variant in MSA.

The prognostic effect of single and multiple cancer-related somatic mutations in resected non-small-cell lung cancer

INTRODUCTION

Somatic mutations are becoming increasingly important biomarkers for treatment selection and outcome in patients with non-small-cell lung cancer (NSCLC). The role of multiple somatic mutations in early-stage NSCLC is unclear.

METHODS

Tissue from 214 patients with resected NSCLC at the Princess Margaret Cancer Centre was analyzed by next-generation sequencing by Mi-SEQ or Sequenom multiplex platforms. Associations between mutation status, baseline patient characteristics and outcomes (disease-free survival (DFS) after surgical resection and overall survival (OS)) were investigated.

RESULTS

Somatic mutations were identified in 184 patients with resected stage I-III NSCLC: None (n = 30), single (n = 101) and multiple (≥2, n = 83). Multiple mutations were significantly associated with younger age (p = 0.0006), female sex (p = 0.012), smoking status (p = 0.002) and adenocarcinoma histology (p = 0.0001).TP53, KRAS and EGFR were the most common mutations. TP53 mutation was the most frequent co-mutation occurring in 72% of patients with multiple mutations. In resected stage I-III patients, multiple mutations were significantly associated with worse DFS (HR = 2.56, p = 0.003) but not OS on univariate analysis. Patients with KRAS and EGFR mutations were also associated with shorter DFS (HR = 2.52, p = 0.016 and HR = 4.37, p = 0.001 respectively) but no OS difference. TP53 mutation was associated with both shorter DFS (HR = 2.21, p = 0.02) and OS (HR = 3.08, p = 0.02). In subgroup univariate analysis, poorer DFS was associated with multiple mutations (p = 0.0015), EGFR (HR = 3.14, p = 0.006), and TP53 (HR = 2.46, p = 0.018) in patients with stage I disease.

CONCLUSION

The presence of known somatic mutations is associated with worse DFS in resected NSCLC. The differences are both statistically significant and clinically relevant. The presence of EGFR, KRAS and TP53 mutations was also associated with adverse outcomes. Larger datasets are required to validate whether mutational status is an independent prognostic factor in early stage NSCLC.

Application of interspecific Somatic Cell Nuclear Transfer (iSCNT) in sturgeons and an unexpectedly produced gynogenetic sterlet with homozygous quadruple haploid

Somatic cell nuclear transfer (SCNT) is a very promising cloning technique for reconstruction of endangered animals. The aim of the present research is to implement the interspecific SCNT (iSCNT) technique to sturgeon; one fish family bearing some of the most critically endangered species. We transplanted single cells enzymatically isolated from a dissociated fin-fragment of the Russian sturgeon (Acipenser gueldenstaedtii) into non-enucleated eggs of the sterlet (Acipenser ruthenus), two species bearing different ploidy (4n and 2n, respectively). Up to 6.7% of the transplanted eggs underwent early development, and one feeding larva (0.5%) was successfully produced. Interestingly, although this transplant displayed tetraploidism (4n) as the donor species, the microsatellite and species-specific analysis showed recipient-exclusive homozygosis without any donor markers. Namely, with regards to this viable larva, host genome duplication occurred twice to form tetraploidism during its early development, probably due to iSCNT manipulation. The importance of this first attempt is to apply iSCNT in sturgeon species, establishing the crucial first steps by adjusting the cloning-methodology in sturgeon's biology. Future improvements in sturgeon's cloning are necessary for providing with great hope in sturgeon's reproduction.

Enhanced recovery pathways in thoracic surgery: the Quebec experience

Background

Canada has a universal public health system where all resources must be allocated to optimize cost-effectiveness. Rapid diagnostic assessment programs (DAPs) and enhanced recovery protocols (ERPs) may improve timeliness of care and postoperative outcomes and thus reduce costs. The use of DAPs and ERPs in lung cancer patients who undergo lobectomy via video-assisted thoracoscopic surgery (VATS) is still controversial. This study measured the time between preoperative workup and treatment with a DAP and evaluated the impact of an ERP postoperatively in patients with early-stage non-small cell lung cancer (NSCLC) who received a VATS lobectomy.

Methods

We conducted a retrospective review of patients who underwent minimally invasive lobectomy for the primary treatment of lung cancer from January 2014 through May 2017 at our institution. Timelines of care were measured. Postoperatively, the duration of chest tube drainage, length of hospital stay, and incidence of complications were noted.

Results

During the study period, 646 patients underwent VATS lobectomy for stage I or II NSCLC; of these, 384 (59%) were assessed within the DAP. Using the DAP, the median time between the patient's first clinic visit and referral to surgery was 30.0 days [interquartile range (IQR), 21.0-40.0 days), and the median time between surgical consult and treatment was 29.0 days (IQR, 15.0-47.5 days). With the ERP, the median duration of chest drainage was 3.0 days (IQR, 2.0-6.0 days), and median hospital stay was 4.0 days (IQR, 3.0-7.0 days).

Conclusions

DAPs and ERPs have promising roles in thoracic surgical practice. A rapid DAP can expedite the care trajectory of patients with lung cancer and has allowed our institution to adhere to governmental standards for the management of lung cancer. ERPs are feasible to establish and can effectively improve clinical outcomes.

The nitrogen concentration effect on Ce doped SiOxNy emission: towards optimized Ce3+ for LED applications

Ce-Doped SiO_xN_y films are deposited by magnetron reactive sputtering from a CeO₂ target under a nitrogen reactive gas atmosphere. Visible photoluminescence measurements regarding the nitrogen gas flow reveal a large emission band centered at 450 nm for a sample deposited under a 2 sccm flow. Special attention is paid to the origin of such an emission at high nitrogen concentration. Different emitting centers are suggested in Ce doped SiO_xN_y films (e.g. band tails, CeO₂, Ce clusters, Ce³⁺ ions), with different activation scenarios to explain the luminescence. X-ray photoelectron spectroscopy (XPS) reveals the exclusive presence of Ce³⁺ ions whatever the nitrogen or Ce concentrations, while transmission electron microscopy (TEM) shows no clusters or silicates upon high temperature annealing. With the help of photoluminescence excitation spectroscopy (PLE), a wide excitation range from 250 nm up to 400 nm is revealed and various excitations of Ce³⁺ ions are proposed involving direct or indirect mechanisms. Nitrogen concentration plays an important role in Ce³⁺ emission by modifying Ce surroundings, reducing the Si phase volume in SiO_xN_y and causing a nephelauxetic effect. Taking into account the optimized nitrogen growth parameters, the Ce concentration is analyzed as a new parameter. Under UV excitation, a strong emission is visible to the naked eye with high Ce³⁺ concentration (6 at%). No saturation of the photoluminescence intensity is observed, confirming again the lack of Ce cluster or silicate phase formation due to the nitrogen presence.

Multiple system atrophy and apolipoprotein E

BACKGROUND

Dysregulation of the specialized lipid metabolism involved in myelin synthesis and maintenance by oligodendrocytes has been associated with the unique neuropathology of MSA. We hypothesized that apolipoprotein E, which is associated with neurodegeneration, may also play a role in the pathogenesis of MSA.

OBJECTIVE

This study evaluated genetic associations of Apolipoprotein E alleles with risk of MSA and α-synuclein pathology, and also examined whether apolipoprotein E isoforms differentially affect α-synuclein uptake in a oligodendrocyte cell.

METHODS

One hundred sixty-eight pathologically confirmed MSA patients, 89 clinically diagnosed MSA patients, and 1,277 control subjects were genotyped for Apolipoprotein E. Human oligodendrocyte cell lines were incubated with α-synuclein and recombinant human apolipoprotein E, with internalized α-synuclein imaged by confocal microscopy and cells analyzed by flow cytometry.

RESULTS

No significant association with risk of MSA or was observed for either Apolipoprotein E ɛ2 or ɛ4. α-Synuclein burden was also not associated with Apolipoprotein E alleles in the pathologically confirmed patients. Interestingly, in our cell assays, apolipoprotein E ɛ4 significantly reduced α-synuclein uptake in the oligodendrocytic cell line.

CONCLUSIONS

Despite differential effects of apolipoprotein E isoforms on α-synuclein uptake in a human oligodendrocytic cell, we did not observe a significant association at the Apolipoprotein E locus with risk of MSA or α-synuclein pathology. © 2018 International Parkinson and Movement Disorder Society.

Development of a Simple Hydroponic Assay to Study Vertical and Horizontal Resistance of Soybean and Pathotypes of Phytophthora sojae

Phytophthora root rot, caused by Phytophthora sojae, is one of the most damaging diseases of soybean and the introgression of Rps (Resistance to P. sojae) genes into elite soybean lines is arguably the best way to manage this disease. Current bioassays to phenotype the gene-for-gene relationship are hampered with respect to reproducibility and long-term stability of isolates, and do not accurately predict horizontal resistance individually. The aim of our study was to investigate a new way of phenotyping P. sojae isolates and vertical and horizontal resistance in soybean that relies on zoospores inoculated directly into a hydroponic system. Inoculation of P. sojae isolates against a set of eight differentials accurately and reproducibly identified pathotypes over a period of two years. When applied to test vertical resistance of soybean lines with known and unknown Rps genes, the bioassay relied on plant dry weight to correctly identify all genes. In addition, simultaneous inoculations of three P. sojae isolates, collectively carrying eight major virulence factors against 64 soybean lines with known and unknown levels of horizontal resistance, separated the plants into five distinct groups of root rot, allowing the discrimination of lines with various degrees of partial resistance. Based on those results, this bioassay offers several advantages in facilitating efforts in breeding soybean for P. sojae resistance and in identifying virulence factors in P. sojae.

Wait times for diagnosis and treatment of lung cancer: a single-centre experience

Background

Multiple clinical practice guidelines recommend rapid evaluation of patients with suspected lung cancer. It is uncertain whether delays in diagnosis and management have a negative effect on outcomes.

Methods

This retrospective study included 551 patients diagnosed with lung cancer through the diagnostic assessment program at the Institut universitaire de cardiologie et de pneumologie de Québec between September 2013 and March 2015. Median wait times between initial referral, diagnosis, and first treatment were calculated and compared with recommended targets. Analyses were performed to evaluate for specific factors associated with longer wait times and for the effect of delays on the outcomes of progression-free survival (pfs), relapse-free survival (rfs) after primary surgical resection, and overall survival (os).

Results

Most patients were investigated and treated within recommended targets. Of the entire cohort, 379 patients were treated at our institution. Of those 379 patients, 311 (82%) were treated within recommended targets. In comparing patients within and outside target times, the only statistically significant difference was found in the distribution of treatment modalities: patients meeting targets were more likely to be treated with surgery or chemotherapy rather than with radiation. The pfs on first treatment modality was influenced by clinical stage, but not by time to therapy [hazard ratio (hr): 1.10; p = 0.65]. The os for the entire cohort was also influenced by stage, but not by delays (hr: 1.04; p = 0.87). For the 209 patients treated by surgery with curative intent, a significant reduction in rfs was associated with male sex and TNM stage, but not with delays (hr: 1.11; p = 0.83). The os after primary surgical resection was also associated with TNM stage, but not with delays (hr: 1.82; p = 0.43).

Conclusions

Recommended targets for wait times in the investigation and treatment of lung cancer can be achieved within a diagnostic assessment program. Compared with radiation treatment, treatment with surgery or chemotherapy is more likely to be completed within targets. Delays in investigation and treatment do not appear to negatively affect the clinical outcomes of os, rfs, and pfs. Prospective studies are needed to evaluate whether efficient work-up and treatment influence other important variables, such as quality of life, cost of care, and access to therapies while performance status is adequate.