Prognostic and predictive effects of TP53 co-mutation in patients with EGFR-mutated non-small cell lung cancer (NSCLC)

INTRODUCTION

TP53 mutations are common in non-small cell lung cancer (NSCLC) and have been reported as prognostic of poor outcome. The impact of TP53 co-mutations in epidermal growth factor receptor (EGFR)-mutated NSCLC is unclear.

MATERIALS AND METHODS

Tissue from 105 patients with EGFR-mutated NSCLC at Princess Margaret Cancer Centre was analyzed by next-generation or Sanger sequencing to determine TP53 mutational status. Associations between TP53 status and baseline patient and tumor characteristics, treatments and outcomes (relapse-free survival [RFS] after surgical resection, overall survival [OS], overall response rate [ORR] and progression-free survival [PFS] on EGFR tyrosine kinase inhibitors [TKIs]), were investigated.

RESULTS

Dual TP53/EGFR mutations were found in 43/105 patients (41%). Among 76 patients who underwent surgical resection, neither RFS (HR 0.99, CI 0.56-1.75, p=0.96) nor OS (HR 1.39, CI 0.70-2.77; p=0.35) was associated with TP53 status. Sixty patients (24 TP53 MUT; 36 TP53 WT) received first-generation EGFR TKIs for advanced disease. ORR was not significantly different (TP53 MUT 54%, WT 66%, p=0.42). There was a non-significant trend towards shorter PFS on EGFR TKIs with TP53 mutation (HR 1.74, CI 0.98-3.10, p=0.06). When limited to TP53 missense mutations (n=17), PFS was significantly shorter (HR 1.91, CI 1.01-3.60, p=0.04). Among 11 evaluable patients treated with T790M inhibitors, ORR was not significantly different (TP53 MUT 3/3 [100%], WT 7/8 [88%]).

CONCLUSIONS

Patients with dual TP53/EGFR mutations, especially missense mutations, had marginally lower response rates and shorter PFS when treated with EGFR TKI therapy. Larger datasets are required to validate these observations.

The effect of cryoprotectant agents on DNA methylation patterns and progeny development in the spermatozoa of Colossoma macropomum

DNA methylation patterns are inherited from parents and are imperative for proper embryonic development; however, alterations in these patterns can compromise fertilization and development into a fully functioning adult animal because DNA methylation is part of a complex program of gene transcription. In this study, we investigated the impact of cryoprotectant agents (CPAs) on DNA methylation patterns in spermatozoa and the consequences on embryonic development and the survival rate of progeny. Global methylation was assessed by enzymatic reactions in Colossoma macropomum spermatozoa that were cryopreserved using dimethylsulfoxide, dimethylformamide, methanol, ethyl glycol and glycerol as CPAs. Fertilization was carried out to evaluate survival rates and abnormalities in embryonic development upon treatment with each of the CPAs. Fresh semen served as the control. Our results indicated that, compared to the control group, spermatozoa cryopreservation decreased the fertilization rate and delayed embryonic development from the midblastula stage. Furthermore, spermatozoa cryopreserved in all CPAs had lower methylation levels and exhibited more delays and abnormalities during embryonic development than did fresh semen. Methanol resulted in fertilization, hatching rates and embryonic development that were closer to the control but had lower methylation levels. In conclusion, ours results show significant alterations on spermatozoa DNA methylation patterns caused by CPAs that are used in the semen cryopreservation process. DNA methylation pattern alterations affected the viability of progeny (r=0.48); however, these effects can be minimized by choosing the CPA that will compose the freezing solution.

Molecular basis of spermatogenesis and sperm quality

Spermatozoan quality can be evaluated in different ways, here we focus on the analysis of DNA, RNA and epigenetic status of germ cells. These characterizations also can be the bases for explaining sperm quality at other levels, so we will see how some of these molecules could affect other sperm quality markers. Moreover, we consider the possibility of using some of these molecules as predictors of sperm quality in terms of the ability to produce healthy offspring. The relevant effect of different types of RNA molecules in germ line specification and spermatogenesis and the importance of germ cell DNA integrity and a proper epigenetic pattern will be also discussed. Although most studies at this level have been performed in mammals, some information is available for fish; these recent discoveries in fish models are included. We provide a general overview on how these molecules could have a deep influence in the final sperm quality.

Cryobanking of aquatic species

This review is focused on the applications of genome cryobanking of aquatic species including freshwater and marine fish, as well as invertebrates. It also reviews the latest advances in cryobanking of model species, widely used by the scientific community worldwide, because of their applications in several fields. The state of the art of cryopreservation of different cellular types (sperm, oocytes, embryos, somatic cells and primordial germ cells or early spermatogonia) is discussed focusing on the advantages and disadvantages of each procedure according to different applications. A special review on the need of standardization of protocols has also been carried out. In summary, this comprehensive review provides information on the practical details of applications of genome cryobanking in a range of aquatic species worldwide, including the cryobanks established in Europe, USA, Brazil, Australia and New Zealand, the species and type of cells that constitute these banks and the utilization of the samples preserved.

STATEMENT OF RELEVANCE

This review compiles the last advances on germplasm cryobanking of freshwater and marine fish species and invertebrates, with high value for commercial aquaculture or conservation. It is reviewed the most promising cryopreservation protocols for different cell types, embryos and larvae that could be applied in programs for genetic improvement, broodstock management or conservation of stocks to guarantee culture production.

Structural and emission properties of Tb3+-doped nitrogen-rich silicon oxynitride films

Terbium doped silicon oxynitride host matrix is suitable for various applications such as light emitters compatible with CMOS technology or frequency converter systems for photovoltaic cells. In this study, amorphous Tb³⁺ ion doped nitrogen-rich silicon oxynitride (NRSON) thin films were fabricated using a reactive magnetron co-sputtering method, with various N₂ flows and annealing conditions, in order to study their structural and emission properties. Rutherford backscattering (RBS) measurements and refractive index values confirmed the silicon oxynitride nature of the films. An electron microscopy analysis conducted for different annealing temperatures (T _A) was also performed up to 1200 °C. Transmission electron microscopy (TEM) images revealed two different sublayers. The top layer showed porosities coming from a degassing of oxygen during deposition and annealing, while in the region close to the substrate, a multilayer-like structure of SiO₂ and Si₃N₄ phases appeared, involving a spinodal decomposition. Upon a 1200 °C annealing treatment, a significant density of Tb clusters was detected, indicating a higher thermal threshold of rare earth (RE) clusterization in comparison to the silicon oxide matrix. With an opposite variation of the N₂ flow during the deposition, the nitrogen excess parameter (N_ex) estimated by RBS measurements was introduced to investigate the Fourier transform infrared (FTIR) spectrum behavior and emission properties. Different vibration modes of the Si-N and Si-O bonds have been carefully identified from the FTIR spectra characterizing such host matrices, especially the 'out-of-phase' stretching vibration mode of the Si-O bond. The highest Tb³⁺ photoluminescence (PL) intensity was obtained by optimizing the N incorporation and the annealing conditions. In addition, according to these conditions, the integrated PL intensity variation confirmed that the silicon nitride-based host matrix had a higher thermal threshold of rare earth clusterization than its silicon oxide counterpart. Analysis of time-resolved PL intensity versus T _A showed the impact of Tb clustering on decay times, in agreement with the TEM observations. Finally, PL and PL excitation (PLE) experiments and comparison of the related spectra between undoped and Tb-doped samples were carried out to investigate the impact of the band tails on the excitation mechanism of Tb³⁺ ions.

Health utility scores (HUS) and health-related quality of life (HRQoL) in stage 4 lung cancer (S4LC) patients with brain metastases (BM)

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Background: Novel therapies have improved the survival of S4LC patients, particularly those with EGFR or ALK alterations. As BM are common among such patients, determining whether HUS appropriately capture BM-specific HRQoL is crucial in economic analyses. We evaluated the relationship between the FACT-Brain (Br) HRQoL, presence of BM, and HUS. Methods: This cross-sectional study of S4LC outpatients at a comprehensive cancer centre assessed FACT-Br and EQ-5D-3L-derived HUS. Correlational analyses, stratified by BM status, were performed between HUS and each of FACT-Br and its subscales: FACT-General (G), physical well-being (PWB), social well-being (SWB), emotional well-being (EWB), functional well-being (FWB), and brain cancer (BrC). Linear regression interaction models assessed whether BM modified the associations between FACT-Br or its subscales and HUS. Results: The 65 BM and 42 non-BM patients had similar demographics: median age (range) was 62 (30-83) years, 61% were female, 55% were Caucasian, and 54% were EGFR/ ALK+. Mean± standard error of the mean (SEM) values of HUS were similar between BM and non-BM groups (0.77±0.02 vs. 0.78±0.02; p=0.49). However, 40 BM patients with stable brain disease had higher HUS than the 14 with progressive disease (0.81 vs. 0.69; p=0.007). Mean±SEM values for FACT-Br, FACT-G, and BrC were 148±2.6, 79±1.5, and 69±1.3, respectively, with no differences between BM and non-BM groups. With the exception of SWB, FACT-Br and its subscales were each individually correlated with HUS (all p<0.001 unless specified), including between HUS and PWB (all patients: r=0.58; BM only: r=0.60; non-BM only: r=0.54), FACT-Br (all: r=0.55; BM: r=0.55; non-BM: r=0.54), FACT-G (all: r=0.51; BM: r=0.49; non-BM: r=0.55), and BrC (all: r=0.49; BM: r=0.51; non-BM: r=0.44, p=0.003). Having BM did not modify these relationships (each interaction, p>0.35). Conclusions: The FACT-Br HRQoL measures and the majority of its subcomponents moderately correlate with HUS but are not specific to patients with BM. Progression of CNS disease greatly alters HUS. EQ-5D-3L-derived HUS are a useful index of HRQoL in S4LC.

The impact of neurocognitive function on health utility scores (HUS) in Stage 4 (S4) lung cancer patients (pts) with and without brain metastases (BrM)

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Background: As targeted therapies for S4LC pts have improved survival, the impact of health-related quality of life (HRQoL) in these pts grows in importance. In pts with BrM, loss of NCF may affect HRQoL significantly. We evaluated the relationship between NCF and HUS as a measure of HRQoL in S4LC pts. Methods: Self-reported HUS data from EQ5D-3L were obtained cross-sectionally from S4LC pts with (BrM) or without BrM (non-BrM). NCF was measured using the Hopkins Verbal Learning Test – Revised (HVLT-R), the Controlled Oral Word Association Test (COWAT) and Trail Making Tests (TMT-A/B). NCF scores were correlated with HUS (Pearson Coefficient, R). Results: BrM (n = 54) and non-BrM (n = 40) patients had similar demographics- overall median age was 61 (range 33-89) years; 59% were female; 45% had EGFR/ALK alterations; BrM pts were treated with whole brain (n = 20), stereotactic radiation (n = 19), both (n = 6), or sole use of systemic agents (n = 6); 3 were observed; 7 had BrM resection. Overall HUS were similar between BrM and non-BrM groups (mean HUS (mHUS): 0.77 vs. 0.78; p = 0.86). However, pts with stable brain disease had higher HUS than those with progressive brain disease (mHUS: 0.80 (n = 36) vs 0.69 (n = 17); p = 0.045). There was a trend towards lower HUS in symptomatic vs. asymptomatic BrM (mHUS: 0.70 (n = 10) vs. 0.78 (n = 43); p = 0.07). Multiple correlations between NCF scores and HUS were found. HLVT-Total Recall correlated with HUS in BrM but not non-BrM (R=0.35, p = 0.01; vs. non- R=0.04, p = 0.84 respectively) as did the HLVT-Recognition (BrM: R=0.32, p = 0.03 vs. non-BrM: R=0.13, p = 0.51). In contrast, TMT-A/B were associated with HUS in both BrM (p = 0.03, 0.06) and non-BrM pts (p = 0.001, 0.03). COWAT was associated with HUS only when all pts were analyzed together (p = 0.04). Conclusions: In S4LC pts, HUS were correlated with multiple measures of NCF. The impact of uncontrolled brain disease and poor NCF on HUS demonstrates that this measure has clinical utility, with important HRQoL implications as metastatic lung cancer pts live longer.

Real-World EQ5D Health Utility Scores for Patients With Metastatic Lung Cancer by Molecular Alteration and Response to Therapy

INTRODUCTION

Economic analyses of upcoming treatments for lung cancer benefit from real-world health utility scores (HUSs) in an era of targeted therapy.

METHODS

A longitudinal cohort study at Princess Margaret Cancer Centre evaluated 1571 EQ5D-3L-derived HUSs in 475 outpatients with metastatic lung cancer across various disease states. Patients with epidermal growth factor receptor (EGFR) (n = 183) and anaplastic lymphoma kinase (ALK) (n = 38) driver alterations were enriched through targeted enrolment; patients with wild-type non-small-cell lung cancer (WT NSCLC) (n = 224) and small-cell lung cancer (SCLC) (n = 30) were sampled randomly.

RESULTS

For patients stable on most appropriate treatment, the mean HUSs were 0.81 and 0.82 in patients receiving EGFR and ALK tyrosine kinase inhibitors (TKIs) respectively (with similar HUSs across agents), which were higher than patients with WT NSCLC (0.78; P = .04) and SCLC receiving chemotherapy (0.72; P = .06). In mutation-specific comparisons, disease stability on appropriate therapy resulted in significantly higher mean HUSs (P < .002-.02) than when disease was progressing (mean HUS: EGFR, 0.70; ALK, 0.69; WT NSCLC, 0.66; SCLC, 0.52). When evaluating treatment-related toxicities, significant inverse relationships were observed between HUS and the severity of fatigue and decreased appetite in the EGFR group. There was also a significant inverse relationship between the total number of clinically significant symptoms and HUS, both in patients who were EGFR-mutated and patients with WT NSCLC.

CONCLUSIONS

In a North American setting, HUSs generated from patients with metastatic lung cancer are higher in treated, stable patients carrying driver mutations. This is partially explainable by treatment toxicity and patient symptom differences. Such differences in scores should be considered in economic analyses.

Epigenetic regulation in Parkinson's disease

Recent efforts have shed new light on the epigenetic mechanisms driving gene expression alterations associated with Parkinson's disease (PD) pathogenesis. Changes in gene expression are a well-established cause of PD, and epigenetic mechanisms likely play a pivotal role in regulation. Studies in families with PD harboring duplications and triplications of the SNCA gene have demonstrated that gene dosage is associated with increased expression of both SNCA mRNA and protein, and correlates with a fulminant disease course. Furthermore, it is postulated that even subtle changes in SNCA expression caused by common variation is associated with disease risk. Of note, genome-wide association studies have identified over 30 loci associated with PD with most signals located in non-coding regions of the genome, thus likely influencing transcript expression levels. In health, epigenetic mechanisms tightly regulate gene expression, turning genes on and off to balance homeostasis and this, in part, explains why two cells with the same DNA sequence will have different RNA expression profiles. Understanding this phenomenon will be crucial to our interpretation of the selective vulnerability observed in neurodegeneration and specifically dopaminergic neurons in the PD brain. In this review, we discuss epigenetic mechanisms, such as DNA methylation and histone modifications, involved in regulating the expression of genes relevant to PD, RNA-based mechanisms, as well as the effect of toxins and potential epigenetic-based treatments for PD.

Monitoring and Management of Immune-Related Adverse Events Associated With Programmed Cell Death Protein-1 Axis Inhibitors in Lung Cancer

Monoclonal antibodies targeting programmed cell death protein-1 (PD-1) represent a new treatment paradigm in non-small cell lung cancer. Three phase III trials have demonstrated a survival benefit and improved tolerability of nivolumab and pembrolizumab when compared with standard second-line chemotherapy. Nevertheless, the adverse events associated with PD-1 inhibitors are unique; early recognition and treatment are essential. This review summarizes the required monitoring and appropriate management of immune-related adverse events in lung cancer patients receiving these agents.

THE ONCOLOGIST

2017;22:70-80 IMPLICATIONS FOR PRACTICE: : The potential adverse events of immune checkpoint inhibitors differ from conventional chemotherapy and can require a multidisciplinary approach. Continued education is important for all physicians to ensure optimal care for patients.

TREM2 p.R47H substitution is not associated with dementia with Lewy bodies

Dementia with Lewy bodies (DLB) is the second leading cause of neurodegenerative dementia in the elderly and is clinically characterized by the presence of cognitive decline, parkinsonism, REM sleep behavior disorder, and visual hallucinations.(1,2) At autopsy, α-synuclein-positive Lewy-related pathology is observed throughout the brain. Concomitant Alzheimer disease-related pathology including amyloid plaques and, to a lesser degree, neurofibrillary tangles are often present.(2) The clinical characteristics of DLB share overlapping features with Alzheimer disease dementia (AD) and Parkinson disease (PD). A recent genetic association study examining known hits from PD and AD identified variants at both the α-synuclein (SNCA) and APOE loci as influencing the individual risk to DLB.(3) These findings would suggest that DLB may be a distinct disease with shared genetic risk factors with PD and AD.

LRRK2 variation and dementia with Lewy bodies

INTRODUCTION

The leucine-rich repeat kinase 2 (LRRK2) gene contains several variants that cause Parkinson's disease (PD) and others that modify PD risk. However, little is known about the role of LRRK2 in dementia with Lewy bodies (DLB). Aims of this study were to screen DLB patients for pathogenic LRRK2 variants and to evaluate associations between common LRRK2 variants and risk of DLB.

METHODS

417 clinical DLB patients and 1790 controls were included in the primary analysis. Additionally, 355 Lewy body disease patients assessed as having a high likelihood of clinical DLB based on neuropathological findings were included in secondary analysis. Seven pathogenic LRRK2 variants were assessed in patients, while 17 common LRRK2 exonic variants and 1 GWAS-nominated common LRRK2 PD-risk variant were evaluated for association with DLB.

RESULTS

We identified carriers of 2 different pathogenic LRRK2 variants. One clinical DLB patient was a p.G2019S carrier, while in the pathological high likelihood DLB series there was one carrier of the p.R1441C mutation. However, examination of clinical records revealed the p.R1441C carrier to have PD with dementia. Evaluation of common variants did not reveal any associations with DLB risk after multiple testing adjustment. However, a non-significant trend similar to that previously reported for PD was observed for the protective p.N551K-R1398H-K1423K haplotype in the clinical DLB series (OR: 0.76, P = 0.061).

CONCLUSION

LRRK2 does not appear to play a major role in DLB, however further study of p.G2019S and the p.N551K-R1398H-K1423K haplotype is warranted to better understand their involvement in determining DLB risk.

MAPT haplotype diversity in multiple system atrophy

INTRODUCTION

Multiple system atrophy (MSA) is a rare progressive neurodegenerative disorder. MSA was originally considered exclusively sporadic but reports of association with genes such as SNCA, COQ2 and LRRK2 have demonstrated that there is a genetic contribution to the disease. MAPT has been associated with several neurodegenerative diseases and we previously reported a protective association of the MAPT H2 haplotype with MSA in 61 pathologically confirmed cases.

METHODS

In the present study, we assessed the full MAPT haplotype diversity in MSA patients using six MAPT tagging SNPs. We genotyped a total of 127 pathologically confirmed MSA cases, 86 patients with clinically diagnosed MSA and 1312 controls.

RESULTS

We identified four significant association signals in our pathologically confirmed cases, two from the protective haplotypes H2 (MSA:16.2%,

CONTROLS

22.7%, p = 0.024) and H1E (MSA:3.0%,

CONTROLS

9.0%, p = 0.014), and two from the rare risk haplotypes H1x (MSA:3.7%,

CONTROLS

1.3%, p = 0.030) and H1J (MSA:3.0%,

CONTROLS

0.9%, p = 0.021). We evaluated the association of MSA subtypes with the common protective H2 haplotype and found a significant difference with controls for MSA patients with some degree of MSA-C (MSA-C or MSA-mixed), for whom H2 occurred in only 8.6% of patients in our pathologically confirmed series (P < 0.0001).

CONCLUSIONS

Our findings provide further evidence that MAPT variation is associated with risk of MSA. Interestingly, our results suggest a greater effect size in the MSA-C compared to MSA-P for H2. Additional genetic studies in larger pathologically confirmed MSA series and meta-analytic studies will be needed to fully assess the role of MAPT and other genes in MSA.

MAPT haplotype H1G is associated with increased risk of dementia with Lewy bodies

INTRODUCTION

The MAPT H1 haplotype has been associated with several neurodegenerative diseases. We were interested in exploring the role of MAPT haplotypic variation in risk of dementia with Lewy bodies (DLB).

METHOD

We genotyped six MAPT haplotype tagging SNPs and screened 431 clinical DLB cases, 347 pathologically defined high-likelihood DLB cases, and 1049 controls.

RESULT

We performed haplotypic association tests and detected an association with the protective H2 haplotype in our combined series (odds ratio [OR] = 0.75). We fine-mapped the locus and identified a relatively rare haplotype, H1G, that is associated with an increased risk of DLB (OR = 3.30, P = .0017). This association was replicated in our pathologically defined series (OR = 2.26, P = .035).

DISCUSSION

These results support a role for H1 and specifically H1G in susceptibility to DLB. However, the exact functional variant at the locus is still unknown, and additional studies are warranted to fully explain genetic risk of DLB at the MAPT locus.

RAB39B gene mutations are not a common cause of Parkinson's disease or dementia with Lewy bodies

Mutations in Ras-related protein Rab-39B (RAB39B) gene have been linked to X-linked early-onset Parkinsonism with intellectual disabilities. The aim of this study was to address the genetic contribution of RAB39B to Parkinson's disease (PD), dementia with Lewy bodies (DLB), and pathologically confirmed Lewy body dementia (pLBD) cases. A cohort of 884 PD, 399 DLB, and 379 pLBD patients were screened for RAB39B mutations, but no coding variants were found, suggesting RAB39B mutations are not a common cause of PD, DLB, or pLBD in Caucasian population.

Cerebellar ataxia in progressive supranuclear palsy: An autopsy study of PSP-C

BACKGROUND

Cerebellar ataxia is an exclusion criterion for the clinical diagnosis of progressive supranuclear palsy, but a variant with predominant cerebellar ataxia has been reported. The aims of this study were to estimate the frequency of progressive supranuclear palsy with predominant cerebellar ataxia in an autopsy series from the United States and to compare clinical, pathologic, and genetic differences between progressive supranuclear palsy with and without predominant cerebellar ataxia.

METHOD

We selected 100 consecutive patients with pathologically confirmed progressive supranuclear palsy who had been evaluated at the Mayo Clinic (referred to as the Mayo Clinic patient series) from our brain bank database (N = 1085). We next enriched in cases likely to have cerebellar ataxia by searching the remaining 985 cases for (1) an antemortem diagnosis of multiple system atrophy or (2) neuropathologic evidence of prominent degeneration of the cerebellum or cerebellar afferent nuclei. Subsequently, clinical, pathologic, and genetic features were compared between the two groups.

RESULTS

One patient in the Mayo Clinic patient series (1%) met criteria for progressive supranuclear palsy with predominant cerebellar ataxia and had both cerebellar and mild midbrain atrophy on MRI. Four patients were identified with the targeted search. Four of the five patients were clinically misdiagnosed as multiple system atrophy. The severity of tau-related pathology and cerebellar degeneration were not different between the two groups. No differences were detected in tau genotypes.

CONCLUSION

Although our data cannot provide definitive information about how to make an accurate clinical diagnosis, they should serve to raise awareness of progressive supranuclear palsy with predominant cerebellar ataxia in the differential diagnosis of multiple system atrophy. © 2016 Movement Disorder Society.

Altered retinoic acid signalling underpins dentition evolution

Small variations in signalling pathways have been linked to phenotypic diversity and speciation. In vertebrates, teeth represent a reservoir of adaptive morphological structures that are prone to evolutionary change. Cyprinid fish display an impressive diversity in tooth number, but the signals that generate such diversity are unknown. Here, we show that retinoic acid (RA) availability influences tooth number size in Cyprinids. Heterozygous adult zebrafish heterozygous for the cyp26b1 mutant that encodes an enzyme able to degrade RA possess an extra tooth in the ventral row. Expression analysis of pharyngeal mesenchyme markers such as dlx2a and lhx6 shows lateral, anterior and dorsal expansion of these markers in RA-treated embryos, whereas the expression of the dental epithelium markers dlx2b and dlx3b is unchanged. Our analysis suggests that changes in RA signalling play an important role in the diversification of teeth in Cyprinids. Our work illustrates that through subtle changes in the expression of rate-limiting enzymes, the RA pathway is an active player of tooth evolution in fish.

Pericardiocentesis versus pericardiotomy for malignant pericardial effusion: a retrospective comparison

BACKGROUND

Treatment of malignant pericardial effusion remains controversial, because no randomized controlled trials have been conducted to determine the best approach, and results of retrospective studies have been inconsistent. The objective of the present study was to compare pericardiocentesis and pericardiotomy with respect to efficacy for preventing recurrence, and to determine, for those two procedures, diagnostic yields, complication rates, and effects on survival. We also aimed to identify clinical and procedural factors that could predict effusion recurrence.

METHODS

We retrospectively assessed 61 patients who underwent a procedure for treatment of a malignant pericardial effusion at the Institut universitaire de cardiologie et de pneumologie de Québec between February 2004 and September 2013.

RESULTS

Pericardiocentesis was performed in 42 patients, and pericardiotomy, in 19 patients. The effusion recurrence rate was significantly higher in patients treated with pericardiocentesis than with pericardiotomy (31.0% vs. 5.3%, p = 0.046). The diagnostic yield of the procedures was not significantly different (92.9% vs. 86.7%, p = 0.6). The overall rate of complications was similar in the two groups, as was the median overall survival (2.4 months vs. 2.6 months, p = 0.5). In univariate analyses, the procedure type was the only predictor of recurrence that approached statistical significance. Age, sex, type of cancer, presence of effusion at the time of cancer diagnosis, prior chest irradiation, tamponade upon presentation, and total volume of fluid removed did not influence the recurrence rate.

CONCLUSIONS

Compared with pericardiocentesis, pericardiotomy had higher success rate in preventing recurrence of malignant pericardial effusion, with similar diagnostic yields, complication rates, and overall survival.

Mitochondrial targeting sequence variants of the CHCHD2 gene are a risk for Lewy body disorders

OBJECTIVE

To assess the role of CHCHD2 variants in patients with Parkinson disease (PD) and Lewy body disease (LBD) in Caucasian populations.

METHODS

All exons of the CHCHD2 gene were sequenced in a US Caucasian patient-control series (878 PD, 610 LBD, and 717 controls). Subsequently, exons 1 and 2 were sequenced in an Irish series (355 PD and 365 controls) and a Polish series (394 PD and 350 controls). Immunohistochemistry and immunofluorescence studies were performed on pathologic LBD cases with rare CHCHD2 variants.

RESULTS

We identified 9 rare exonic variants of unknown significance. These variants were more frequent in the combined group of PD and LBD patients compared to controls (0.6% vs 0.1%, p = 0.013). In addition, the presence of any rare variant was more common in patients with LBD (2.5% vs 1.0%, p = 0.050) compared to controls. Eight of these 9 variants were located within the gene's mitochondrial targeting sequence.

CONCLUSIONS

Although the role of variants of the CHCHD2 gene in PD and LBD remains to be further elucidated, the rare variants in the mitochondrial targeting sequence may be a risk factor for Lewy body disorders, which may link CHCHD2 to other genetic forms of parkinsonism with mitochondrial dysfunction.

Role for the microtubule-associated protein tau variant p.A152T in risk of α-synucleinopathies

OBJECTIVE

To assess the importance of MAPT variant p.A152T in the risk of synucleinopathies.

METHODS

In this case-control study, we screened a large global series of patients and controls, and assessed associations between p.A152T and disease risk. We included 3,229 patients with clinical Parkinson disease (PD), 442 with clinical dementia with Lewy bodies (DLB), 181 with multiple system atrophy (MSA), 832 with pathologically confirmed Lewy body disease (LBD), and 2,456 healthy controls.

RESULTS

The minor allele frequencies (MAF) in clinical PD cases (0.28%) and in controls (0.2%) were not found to be significantly different (odds ratio [OR] 1.37, 95% confidence interval [CI] 0.63-2.98, p = 0.42). However, a significant association was observed with clinical DLB (MAF 0.68%, OR 5.76, 95% CI 1.62-20.51, p = 0.007) and LBD (MAF 0.42%, OR 3.55, 95% CI 1.04-12.17, p = 0.04). Additionally, p.A152T was more common in patients with MSA compared to controls (MAF 0.55%, OR 4.68, 95% CI 0.85-25.72, p = 0.08) but this was not statistically significant and therefore should be interpreted with caution.

CONCLUSIONS

Overall, our findings suggest that MAPT p.A152T is a rare low penetrance variant likely associated with DLB that may be influenced by coexisting LBD and AD pathology. Given the rare nature of the variant, further studies with greater sample size are warranted and will help to fully explain the role of p.A152T in the pathogenesis of the synucleinopathies.

Exonic Re-Sequencing of the Chromosome 2q24.3 Parkinson's Disease Locus

Genome-wide association studies (GWAS) in Parkinson’s disease (PD) have identified over 20 genomic regions associated with disease risk. Many of these loci include several candidate genes making it difficult to pinpoint the causal gene. The locus on chromosome 2q24.3 encompasses three genes: B3GALT1, STK39, and CERS6. In order to identify if the causal variants are simple missense changes, we sequenced all 31 exons of these three genes in 187 patients with PD. We identified 13 exonic variants including four non-synonymous and three insertion/deletion variants (indels). These non-synonymous variants and rs2102808, the GWAS tag SNP, were genotyped in three independent series consisting of a total of 1976 patients and 1596 controls. Our results show that the seven identified 2q24.3 coding variants are not independently responsible for the GWAS association signal at the locus; however, there is a haplotype, which contains both rs2102808 and a STK39 exon 1 6bp indel variant, that is significantly associated with PD risk (Odds Ratio [OR] = 1.35, 95% CI: 1.11–1.64, P = 0.003). This haplotype is more associated than each of the two variants independently (OR = 1.23, P = 0.005 and 1.10, P = 0.10, respectively). Our findings suggest that the risk variant is likely located in a non-coding region. Additional sequencing of the locus including promoter and regulatory regions will be needed to pinpoint the association at this locus that leads to an increased risk to PD.