Epigenotype-genotype-phenotype correlations in SETD1A and SETD2 chromatin disorders

Germline pathogenic variants in two genes encoding the lysine-specific histone methyltransferase genes SETD1A and SETD2 are associated with neurodevelopmental disorders (NDDs) characterized by developmental delay and congenital anomalies. The SETD1A and SETD2 gene products play a critical role in chromatin-mediated regulation of gene expression. Specific methylation episignatures have been detected for a range of chromatin gene-related NDDs and have impacted clinical practice by improving the interpretation of variant pathogenicity. To investigate if SETD1A and/or SETD2-related NDDs are associated with a detectable episignature, we undertook targeted genome-wide methylation profiling of > 2 M CpGs using a next-generation sequencing-based assay. A comparison of methylation profiles in patients with SETD1A variants (n = 6) did not reveal evidence of a strong methylation episignature. A review of the clinical and genetic features of the SETD2 patient group revealed that, as reported previously, there were phenotypic differences between patients with truncating mutations (n = 4, Luscan-Lumish syndrome; MIM:616831) and those with missense codon 1740 variants [p.Arg1740Trp (n = 4) and p.Arg1740Gln (n = 2)]. Both SETD2 subgroups demonstrated a methylation episignature, which was characterized by hypomethylation and hypermethylation events, respectively. Within the codon 1740 subgroup, both the methylation changes and clinical phenotype were more severe in those with p.Arg1740Trp variants. We also noted that two of 10 cases with a SETD2-NDD had developed a neoplasm. These findings reveal novel epigenotype-genotype-phenotype correlations in SETD2-NDDs and predict a gain-of-function mechanism for SETD2 codon 1740 pathogenic variants.

Deleterious functional consequences of perfluoroalkyl substances accumulation into the myelin sheath

Exposure to persistent organic pollutants during the perinatal period is of particular concern because of the potential increased risk of neurological disorders in adulthood. Here we questioned whether exposure to perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) could alter myelin formation and regeneration. First, we show that PFOS, and to a lesser extent PFOA, accumulated into the myelin sheath of postnatal day 21 (p21) mice, whose mothers were exposed to either PFOA or PFOS (20 mg/L) via drinking water during late gestation and lactation, suggesting that accumulation of PFOS into the myelin could interfere with myelin formation and function. In fact, PFOS, but not PFOA, disrupted the generation of oligodendrocytes, the myelin-forming cells of the central nervous system, derived from neural stem cells localised in the subventricular zone of p21 exposed animals. Then, cerebellar slices were transiently demyelinated using lysophosphatidylcholine and remyelination was quantified in the presence of either PFOA or PFOS. Only PFOS impaired remyelination, a deleterious effect rescued by adding thyroid hormone (TH). Similarly to our observation in the mouse, we also showed that PFOS altered remyelination in Xenopus laevis using the Tg(Mbp:GFP-ntr) model of conditional demyelination and measuring, then, the number of oligodendrocytes. The functional consequences of PFOS-impaired remyelination were shown by its effects using a battery of behavioural tests. In sum, our data demonstrate that perinatal PFOS exposure disrupts oligodendrogenesis and myelin function through modulation of TH action. PFOS exposure may exacerbate genetic and environmental susceptibilities underlying myelin disorders, the most frequent being multiple sclerosis.

Germline pathogenic variants in HNRNPU are associated with alterations in blood methylome

HNRNPU encodes a multifunctional RNA-binding protein that plays critical roles in regulating pre-mRNA splicing, mRNA stability, and translation. Aberrant expression and dysregulation of HNRNPU have been implicated in various human diseases, including cancers and neurological disorders. We applied a next generation sequencing based assay (EPIC-NGS) to investigate genome-wide methylation profiling for >2 M CpGs for 7 individuals with a neurodevelopmental disorder associated with HNRNPU germline pathogenic loss-of-function variants. Compared to healthy individuals, 227 HNRNPU-associated differentially methylated positions were detected. Both hyper- and hypomethylation alterations were identified but the former predominated. The identification of a methylation episignature for HNRNPU-associated neurodevelopmental disorder (NDD) implicates HNPRNPU-related chromatin alterations in the aetiopathogenesis of this disorder and suggests that episignature profiling should have clinical utility as a predictor for the pathogenicity of HNRNPU variants of uncertain significance. The detection of a methylation episignaure for HNRNPU-associated NDD is consistent with a recent report of a methylation episignature for HNRNPK-associated NDD.

Work outcomes of breast cancer survivors who returned to work after treatment: CANTO cohort

Background

As survival rates among breast cancer patients improve there is an increasing need to address breast cancer survivors’ (BCS) issues, professional life being a key aspect. Return to work (RTW) of BCS has been largely studied, but studies on job maintenance and its determinants are scarce. We aim to study job maintenance after RTW and the associated factors among BCS.

Methods

We used data from the CANTO cohort, a French prospective cohort of BCS. We included 1643 BCS aged <57 at diagnosis (dx) who returned to work two years after dx. We excluded self-employed BCS. Using multinomial logistic models, we assessed the association between activity status one year after they return to work. (i.e. active, sick leave, or unemployed, retired or invalidity) and sociodemographic, clinical, health status and work-related factors.

Results

Overall, 87% of BCS were active, 10% were on sick leave and 3% were on unemployment, retirement or invalidity one year after they return to work. In the fully adjusted model being on sick leave was associated with stage III at dx (OR: 1.89, 95% CI: 1.11-3.22), being severely fatigued at the moment of returning to work (OR: 1.53, 1.04-2.27), and having workplace accommodations (OR: 1.79, 1.14-2.81). The unemployed, retired, invalidity status was negatively associated with professional life being more than or as important as one’s personal life (OR: 0.51, 0.26-0.98) and being <50 years old (OR: 0.51, 0.27-0.96), and positively associated with having a fixed-term contract (OR: 2.69, 1.39-5.18) and working for a small company (OR: 2.73, 1.24-6.02).

Conclusions

A non-negligible proportion of BCS are non-active one year after they return to work. While clinical factors are associated with sick leave, work related factors are associated with the unemployed, retired, and invalidity status. RTW should not be regarded as the ultimate goal and future policies should focus on ensuring people are ready to return to work and maintain their jobs.

Key messages

• A non-negligible proportion of breast cancer survivors are non-active one year after they return to work.

• Future policies should ensure job maintenance along with return to work.

Predictive Role of Aortic Valve Calcium score on post-procedural outcomes and mortality after Transcatheter aortic valve replacement

Introduction

Extent of aortic valve (AV) calcium increases as degenerative aortic valve stenosis progresses. Initial studies postulated AV calcium (AVC) score to be a predictor of complications such as need for pacemaker implantation, paravalvular regurgitation and mortality after Trans-catheter Aortic valve Replacement (TAVR). However, evidence regarding the impact of AVC score as a predictor of post-procedural complications and mortality has been conflicting.

Objective

This study aimed to determine the prognostic impact of AVC as predictor of post-procedural outcomes and mortality in patients with severe aortic stenosis (AS) who underwent TAVR.

Methods

We retrospectively abstracted the records of 497 patients with severe AS who underwent TAVR between January 2016 and July 2019 at our institution. All patients underwent a non-contrast cardiac CT scan on a Siemens Somatom Definition Flash 128 slice scanner. AVC score using the Agatston method was obtained retrospectively. Patients were divided into two groups: 1) Non-severe AVC score group [women &lt;1200 Agatston unit (AU) and men &lt;2000 AU]; 2) Severe AV Calcium Score group [women &gt;1200 AU and men &gt;2000 AU]. Primary outcome was 1-year mortality.

Results

Among 466 patients included in the analysis, 352 patients were included severe AVC group while 114 patients were in the non-severe AVC group. Patients in the severe AVC group were older (81±8 vs 79±8 years), were predominantly males (79% vs 71%), and had less diabetes mellitus (31% vs 42%, p=0.02). Post-TAVR AV dimensionless index (0.58±0.13 vs 0.58±0.12, p=0.8) and AV mean gradient (9.5±4.9 vs 9.2±5.4 mmHg) were not statistically different between both groups. There was no statistical difference in the need for PPM (12% vs 7%, p=0.16), post-TAVR stroke (1.5% vs 0%), post-TAVR major complications (17.4% vs 10%, p=0.07), 30 day (3.7% vs 4.4%), and 1-year mortality (13.6 vs 11.4, p=0.6) between both groups.

Conclusion

Our study report that the severity of AVC score does not have a prognostic impact on major post-procedural outcomes and mortality after TAVR.

Funding Acknowledgement

Type of funding sources: None.

Sex-based differences of the impact of aortic valve calcium score on mortality and post-procedural outcomes after trans-catheter aortic valve replacement

Introduction

Sex based differences exist in the presentation, outcomes, and management of cardiovascular diseases. Although aortic valve calcium (AVC) score has been postulated to be associated with post-procedural outcomes after transcatheter aortic valve replacement (TAVR), data on the impact of AVC score on procedural outcomes after TAVR based on sex have been scarce.

Objective

The aim of the present study was to elucidate sex related differences in the prognostic impact of AVC score as a predictor of post-procedural outcomes and mortality in patients with severe aortic stenosis (AS) who underwent TAVR.

Methods

We retrospectively abstracted the records of 497 patients with severe AS who underwent TAVR between January 2016 and July 2019 at our institution. All patients underwent a non-contrast cardiac CT scan on a Siemens Somatom Definition Flash 128 slice scanner. AVC score using the Agatston method was calculated retrospectively. Primary outcome was 1-year mortality. Patients were divided into two groups: 1) Non-severe AVC score group [women &lt;1200 Agatston unit (AU) and men &lt;2000 AU]; 2) Severe AVC Score group [women &gt;1200 AU and men &gt;2000 AU]. Cox-regression model was used to predict effect of variables on 1-year mortality in male and female patients.

Results

Among 466 patients included, 268 patients were male and 198 were female (57.5% vs 42.5%). When compared with males, female patients had significantly lower AVC score (p&lt;0.001), aortic valve area (AVA) (p&lt;0.001), obstructive CAD (p&lt;0.001), and history of previous PCI (p&lt;0.004), and CABG (&lt;0.001) but had a significantly higher STS score (6.7±3.2 vs 5.8±3.3 P=0.01). There was no difference between need for permanent pacemaker (PPM) implantation (11% vs 9.6%, p=0.4), major complications (16% vs 15%, p=0.9), stroke (0.8% vs 1.6%, p=0.7), 30-day (3.7% vs 4%, p=0.9), and 1-year mortality (14% vs 12%, p=0.6) between males and females, respectively. Female patients required smaller bio-prosthetic valves compared with males (26±3.2 vs 30±3, p&lt;0.001). Cox regression analysis for female patients showed BMI, hemoglobin level, and AVA independently predicted 1-year mortality, while there was no impact of severe AVC score (&gt;1200 AU) on 1-year mortality in females. Similarly, Cox regression analysis for male patients showed there was no impact of severe AVC score (&gt;2000 AU) on 1-year mortality in males. When males in the severe AVC group were compared with female patients in the severe AVC group, there was no difference in 30 day (4.3% vs 3.3%, p=0.82) and 1-year mortality (14.2% vs 13.3%, p=0.77). Similarly, in the severe AVC group there was no difference between need for PPM implantation (12.8% vs 12.1%, p=0.9), major complications (19.7% vs 15.8%, p=0.4), and stroke (2.2% vs 1%, p=0.6) between males and females, respectively.

Conclusion

There were no sex differences in the impact of AVC score on mortality and post-procedural outcomes after TAVR.

Funding Acknowledgement

Type of funding sources: None.

[Stereotactic radiotherapy for localized primary lung tumours of stage T1-T2]

The historical treatment for stage I non-small cell lung cancer is surgical. Parenchymal amputation is not always possible due to cardiopulmonary comorbidities and stereotactic radiotherapy is one of the alternatives to an invasive procedure. The excellent results observed for inoperable tumors raised the question of this treatment in operable patients. This article presents the data in these two situations and the future perspectives.

Associations between inattention and impulsivity ADHD symptoms and disordered eating risk in a community sample of young adults

BACKGROUND

Symptoms of attention deficit hyperactivity disorder (ADHD) and trait impulsivity have been associated with disordered eating but are seldom assessed in community studies, or longitudinally and little is known about the mediating mechanisms.

METHODS

We tested associations between ADHD symptoms and disordered eating cross-sectionally and between trait impulsivity and disordered eating longitudinally. We utilised data from a normative cohort of young adults (642 participants: 65% female, M_age = 23 years). Participants were classified as high risk or low risk for disordered eating using the SCOFF instrument. In the first two steps of both cross-sectional and longitudinal hierarchical logistic regression models, demographics and covariates were entered. For the cross-sectional regression, Adult ADHD self-report scale (ASRS) scores, separated into inattentive and hyperactive/impulsive symptoms, were entered in the third step. In a separate longitudinal model, Barratt impulsivity scale subscales (attentional, motor and non-planning impulsivity) were entered in the third step. Depression, as assessed by the moods and feelings questionnaire (MFQ), was examined as a mediator.

RESULTS

Cross-sectionally, sex, MFQ score and inattentive symptoms predicted disordered eating risk (model R² = 20%). Longitudinally, sex, MFQ score and attentional impulsivity predicted disordered eating risk (model R² = 16%). The relationship between inattentive symptoms and the disordered eating risk was partially mediated by MFQ score, whereas the relationship between attentional impulsivity and the disordered eating risk was fully mediated by MFQ scores.

CONCLUSIONS

These data highlight (1) a specific role for inattentive symptoms of ADHD and (2) the importance of both depression and impulsivity in predicting eating disorder risk.

Investigating the role of somatic sequencing platforms for phaeochromocytoma and paraganglioma in a large UK cohort

OBJECTIVES

Phaeochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumours with malignant potential and a hereditary basis in almost 40% of patients. Germline genetic testing has transformed the management of PPGL enabling stratification of surveillance approaches, earlier diagnosis and predictive testing of at-risk family members. Recent studies have identified somatic mutations in a further subset of patients, indicating that molecular drivers at either a germline or tumour level can be identified in up to 80% of PPGL cases. The aim of this study was to investigate the clinical utility of somatic sequencing in a large cohort of patients with PPGL in the United Kingdom.

DESIGN AND PATIENTS

Prospectively collected matched germline and tumour samples (development cohort) and retrospectively collected tumour samples (validation cohort) of patients with PPGL were investigated.

MEASUREMENTS

Clinical characteristics of patients were assessed and tumour and germline DNA was analysed using a next-generation sequencing strategy. A screen for variants within 'mutation hotspots' in 68 human cancer genes was performed.

RESULTS

Of 141 included patients, 45 (32%) had a germline mutation. In 37 (26%) patients one or more driver somatic variants were identified including 26 likely pathogenic or pathogenic variants and 19 variants of uncertain significance. Pathogenic somatic variants, observed in 25 (18%) patients, were most commonly identified in the VHL, NF1, HRAS and RET genes. Pathogenic somatic variants were almost exclusively identified in patients without a germline mutation (all but one), suggesting that somatic sequencing is likely to be most informative for those patients with negative germline genetic test results.

CONCLUSIONS

Somatic sequencing may further stratify surveillance approaches for patients without a germline genetic driver and may also inform targeted therapeutic strategies for patients with metastatic disease.

Drosophila CRISPR/Cas9 mutants as tools to analyse cardiac filamin function and pathogenicity of human FLNC variants

Filamins are large proteins with actin binding properties. Mutations in FLNC, one of the three filamin genes in humans, have recently been implicated in dominant cardiomyopathies, but the underlying mechanisms are not well understood. Here, we aimed to use Drosophila melanogaster as a new in vivo model to study these diseases. First, we show that adult-specific cardiac RNAi-induced depletion of Drosophila Filamin (dFil) induced cardiac dilatation, impaired systolic function and sarcomeric alterations, highlighting its requirement for cardiac function and maintenance of sarcomere integrity in the adult stage. Next, we introduced in the cheerio gene, using CRISPR/Cas9 gene editing, three missense variants, previously identified in patients with hypertrophic cardiomyopathy. Flies carrying these variants did not exhibit cardiac defects or increased propensity to form filamin aggregates, arguing against their pathogenicity. Finally, we show that deletions of the C-term part of dFil carrying the last four Ig-like domains are dispensable for cardiac function. Collectively, these results highlight the relevance of this model to explore the cardiac function of filamins and increase our understanding of physio-pathological mechanisms involved in FLNC-related cardiomyopathies.

Factors associated with enrolment in clinical trials among women with early-stage breast cancer

Background

Clinical trials allow development of innovative treatments and ameliorate the quality of clinical care in oncology. Data show that only a minority of patients are enrolled in clinical trials. We assessed enrolment in clinical trials and its correlates among women with early breast cancer.

Methods

We included 9516 patients with stage I-III breast cancer from the multicenter, prospective CANTO study (NCT01993498), followed-up until year 4 (Y4) post-diagnosis. We assessed factors associated with enrolment using multivariable logistic regression. In exploratory, propensity score matched analyses, we used multiple linear regression to evaluate the relationship of enrolment in clinical trials with the European Organisation for Research and Treatment of Cancer Quality Of Life (QoL) questionnaire (EORTC QLQ-C30) Summary Score and described clinical outcomes (distant disease event, invasive disease event, and death by any cause) according to enrolment.

Results

Overall, 1716 patients (18%) were enrolled in a clinical trial until Y4 post-diagnosis of breast cancer. Socioeconomic factors were not associated with enrolment. Centres of intermediate volume were most likely to enrol patients in clinical trials [versus low volume, odds ratio 1.45 (95% confidence interval (CI) 1.08-1.95), P = 0.0124]. Among 2118 propensity score matched patients, enrolment was associated with better QoL at Y4 (adjusted mean difference versus not enrolled 1.37, 95% CI 0.03-2.71, P = 0.0458), and clinical outcomes (enrolled versus not enrolled, distant disease event 7.3% versus 10.1%, P = 0.0206; invasive disease event 8.2% versus 10.5%, P = 0.0732; death by any cause 2.8% versus 3.7%, P = 0.2707).

Conclusions

In this large study, one in five patients enrolled on a clinical trial until Y4 after diagnosis of early breast cancer. Geographical and centre-related factors were significantly associated with enrolment in clinical trials. Inclusion in clinical trials seemed associated with improved QoL and clinical outcomes. Access to innovation for early-stage breast cancer patients should be encouraged and facilitated by overcoming organizational and geographical barriers to recruitment.

•

The proportion of patients who access innovation through participation in clinical trials is generally limited.

•

Rate of enrolment in clinical trials among women with early breast cancer exceeded what previously found in other settings.

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Clinical and geographical factors were associated to access to innovation in clinical trials.

•

Enrolment in clinical trials is associated with better quality of life and clinical outcomes.

[Intermediate-risk prostate cancer treated with exclusive external irradiation: Focus on anatomical sites of recurrence in two French trials]

PURPOSE

Retrospective description of anatomical sites of relapse based on (18F)-choline PET-CT, (68Ga)-prostatic specific-membrane antigen PET-CT, bone scan, and prostate magnetic resonance imaging (MRI) data.

MATERIALS AND METHODS

From two French prospective cohorts, patients treated with exclusive radiotherapy for an intermediate-risk cancer were identified during their follow-ups. They were included if they presented a rising of the prostate-specific antigen (PSA) associated with the realization of an imaging showing the sites of recurrences.

RESULTS

Two hundred and sixty-three patients were included. After a median follow-up of 76 months (interquartile range [IQR] 67-95), 65 patients had biochemical recurrence and positive imaging. The median nadir PSA was 0.6ng/mL and the median PSA at recurrence was 3.4ng/mL. A single lesion was found in 48% of cases, 2 to 4 lesions in 43% of cases and more than 4 lesions in 9% of cases. The sites of relapse identified were prostate (37/65), prostate only (19/65), seminal vesicles (9/65) Pelvic nodes (35/65), extrapelvic nodes (15/65) and bone (13/65).

CONCLUSIONS

The majority of relapses presented as a single lesion localized in the pelvis.

POS1295 SYSTEMIC AND AUTO-INFLAMMATORY DISEASES OF PEDIATRIC ONSET: THE EXPERIENCE OF THE FRENCH OVERSEAS DEPARTMENTS OF AMERICA

Background

Systemic diseases of pediatric onset are more frequent in Afro-Caribbean population, especially Pediatric systemic lupus (pSLE).

Objectives

Our work is a retrospective study of patients followed in French overseas departments of America for systemic disease or auto-inflammatory syndrome of pediatric onset. It describes their clinical and biological specificities at diagnosis, during childhood and early adulthood.

Methods

Our retrospective study was conducted between 01/01/2000 and 01/09/2021. Listings of adult patients with pediatric onset and pediatric patients were obtained in each center through computerized hospital archives, list of patients followed by referent pediatricians and adult specialists in internal medicine and the French National Registry for rare disease. Data were then gathered by going through their medical files. The spectrum of diseases studied included pSLE, Sjogren syndrome, antiphospholipid syndrome (APS), connectivitis, systemic scleroderma, dermatomyositis, Systemic juvenile idiopathic arthritis (sJIA), unclassified auto-inflammatory syndrome.

Results

2148 patients were identified on a 21 year-period, and 135 patients were included. Most patients diagnosed with a systemic pathology (102) suffered from pSLE (53%), followed by dermatomyositis (17%). Average follow up was 8.3 years (0.3 - 25 years), median age at last follow up was 21.2 (14 - 36.7). We found an increase in the number of new diagnoses throughout the years. For pSLE, sex repartition was 4/1 girl/boy and did not vary according to age (p= 0,31). At onset, patients had 10 Sclicc criteria (4-12) and median EULAR/ACR 2019 score was 38 (12 - 54). The combination of typical skin involvement, arthritis and fever was found for 87%. At onset, a third of patients had renal involvement, 15% had Neurolupus and 41% cardiac involvement. All patients had a positive ANA and Anti-DNA antibodies, followed by anti-Ssa/Ssb antibodies (78%), Anti-Sm (78%) and anti RNP (52%). During childhood, 54% had renal involvement and 26% suffered from Neurolupus. Patients suffered in median from 3 flares and 26% suffered from more than 5 flares during childhood. Pre-pubertal patients (26%) had worst outcomes, 93% had renal and / or neurological involvement, they had more flares (median at 5 p = 0,02) and needed an average of 4 background therapies (p = 0,04). Boys seemed to have better disease control at transition to adult care but gender was not an independent predictor of severity during childhood (p = 0,21). 17 patients had dermatomyositis, 29% of them had respiratory involvement during childhood. 33 patients had auto-inflammatory syndromes mostly sJIA (67%), 50% of them had hemophagocytic syndrome during childhood and their disease was controlled by steroids for 64%, 36% needed biotherapy. The overall mortality was 3%.

Conclusion

This is a large cohort of patients of Afro-Caribbean origin with a higher frequency of pSLE. Although the outcomes for these patients were similar to western countries, they had loud symptoms at onset, not corelated to delay at diagnosis. Compared to ethnic studies of North America or Africa, the French health care system being universal and free, the bias related to socio-economic status was lower. This work will continue with the exploration by transcriptomic and genetic tests for early and severe forms to identify the extra-environmental causes. The environmental factors specific to these regions should be explored in additional prospective studies.

Figure 1.

Clinical and biological characteristics of patients with pediatric onset systemic lupus. Orange: clinical signs at onset, Green: immunological profile, Blue: evolutive profile and proportion of organ involvement during childhood. ANA: anti-nuclear antibody.

Disclosure of Interests

None declared

Comparison of methylation episignatures in KMT2B- and KMT2D-related human disorders

Aim & methods: To investigate peripheral blood methylation episignatures in KMT2B-related dystonia (DYT-KMT2B), the authors undertook genome-wide methylation profiling of ∼2 M CpGs using a next-generation sequencing-based assay and compared the findings with those in controls and patients with KMT2D-related Kabuki syndrome type 1 (KS1). Results: A total of 1812 significantly differentially methylated CpG positions (false discovery rate < 0.05) were detected in DYT-KMT2B samples compared with controls. Multi-dimensional scaling analysis showed that the 10 DYT-KMT2B samples clustered together and separately from 29 controls and 10 with pathogenic variants in KMT2D. The authors found that most differentially methylated CpG positions were specific to one disorder and that all (DYT-KMT2B) and most (Kabuki syndrome type 1) methylation alterations in CpG islands were gain of methylation events. Conclusion: Using sensitive methylation profiling methodology, the authors replicated recent reports of a methylation episignature for DYT-KMT2B. These findings will facilitate the development of episignature-based assays to improve diagnostic accuracy.

Elongin C (ELOC/TCEB1)-associated von Hippel-Lindau disease

Around 95% of patients with clinical features that meet the diagnostic criteria for von Hippel-Lindau disease (VHL) have a detectable inactivating germline variant in VHL. The VHL protein (pVHL) functions as part of the E3 ubiquitin ligase complex comprising pVHL, elongin C, elongin B, cullin 2 and ring box 1 (VCB-CR complex), which plays a key role in oxygen sensing and degradation of hypoxia-inducible factors. To date, only variants in VHL have been shown to cause VHL disease. We undertook trio analysis by whole-exome sequencing in a proband with VHL disease but without a detectable VHL mutation. Molecular studies were also performed on paired DNA extracted from the proband's kidney tumour and blood and bioinformatics analysis of sporadic renal cell carcinoma (RCC) dataset was undertaken. A de novo pathogenic variant in ELOC NM_005648.4(ELOC):c.236A>G (p.Tyr79Cys) gene was identified in the proband. ELOC encodes elongin C, a key component [C] of the VCB-CR complex. The p.Tyr79Cys substitution is a mutational hotspot in sporadic VHL-competent RCC and has previously been shown to mimic the effects of pVHL deficiency on hypoxic signalling. Analysis of an RCC from the proband showed similar findings to that in somatically ELOC-mutated RCC (expression of hypoxia-responsive proteins, no somatic VHL variants and chromosome 8 loss). These findings are consistent with pathogenic ELOC variants being a novel cause for VHL disease and suggest that genetic testing for ELOC variants should be performed in individuals with suspected VHL disease with no detectable VHL variant.

ImprintSeq, a novel tool to interrogate DNA methylation at human imprinted regions and diagnose multilocus imprinting disturbance

PURPOSE

Disruptions of genomic imprinting are associated with congenital imprinting disorders (CIDs) and other disease states, including cancer. CIDs are most often associated with altered methylation at imprinted differentially methylated regions (iDMRs). In some cases, multiple iDMRs are affected causing multilocus imprinting disturbances (MLIDs). The availability of accurate, quantitative, and scalable high-throughput methods to interrogate multiple iDMRs simultaneously would enhance clinical diagnostics and research.

METHODS

We report the development of a custom targeted methylation sequencing panel that covered most relevant 63 iDMRs for CIDs and the detection of MLIDs. We tested it in 70 healthy controls and 147 individuals with CIDs. We distinguished loss and gain of methylation per differentially methylated region and classified high and moderate methylation alterations.

RESULTS

Across a range of CIDs with a variety of molecular mechanisms, ImprintSeq performed at 98.4% sensitivity, 99.9% specificity, and 99.9% accuracy (when compared with previous diagnostic testing). ImprintSeq was highly sensitive for detecting MLIDs and enabled diagnostic criteria for MLID to be proposed. In a child with extreme MLID profile a probable genetic cause was identified.

CONCLUSION

ImprintSeq provides a novel assay for clinical diagnostic and research studies of CIDs, MLIDs, and the role of disordered imprinting in human disease states.

869 Colorectal Cancer Referral Pathways: Impact of First Months of COVID-19

Introduction

Whilst daily living has adapted to the “new normal” during Covid-19, colorectal cancer pathways are yet to be revised to reflect this transformation. Government advice to stay at home, hospital avoidance and reduced healthcare access, may be masking a significant proportion of population at risk. We aim to identify changes in colorectal cancer target pathways.

Method

All cancer referrals during the initial Covid-19 period were retrospectively analysed, recording type and date of first clinic and investigation, MDT discussion and decision to treat dates. A comparison was made with referral and treatment data from the same referral period in 2019.

Results

338 referrals were received during March-April 2020, compared to 542 in 2019, indicating a 37.6% decrease. A high proportion of patients were reviewed by telephone clinic (63.4%) rather than face-to-face (23.8%), representing a significant shift in practice. An increasing number of patients were initially investigated by CT(40.2%) instead of endoscopy (37.8%). 51(15.5%) patients were not investigated, with COVID-19 being the commonest reason. 25 patients were diagnosed with colorectal cancer, of which 8(32.0%) breached the investigation and 13(52.0%) the treatment date, both usually postponed due to the pandemic. There was a 66.7% reduction in surgical management compared to 2019.

Conclusions

Two-week wait pathways are strained in the era of Covid-19. As the fight against the global pandemic continues, patients are mostly seen virtually and receive non-gold standard investigation. With fewer patient presentations and elective surgeries, it is important to continue colorectal cancer surveillance and timely treatment, considering possible alternative pathways.

Participation, retention and uptake in a multicentre pre-exposure prophylaxis cohort using online, smartphone-compatible data collection

Objectives

The aim of the study was to assess the feasibility of a national pre‐exposure prophylaxis (PrEP) programme using smartphone‐compatible data collection.

Methods

This was a multicentre cohort study (NCT03893188) enrolling individuals interested in PrEP in Switzerland. All centres participate in the SwissPrEPared programme, which uses smartphone‐compatible data collection. Feasibility was assessed after centres had enrolled at least one participant. Participants were HIV‐negative individuals presenting for PrEP counselling. Outcomes were participation (number enrolled/number eligible), enrolment rates (number enrolled per month), retention at first follow‐up (number with first follow‐up/number enrolled), and uptake (proportion attending first visit as scheduled). Participant characteristics were compared between those retained after baseline assessment and those who dropped out.

Results

Between April 2019 and January 2020, 987 individuals were assessed for eligibility, of whom 969 were enrolled (participation: 98.2%). The median enrolment rate was 86 per month [interquartile range (IQR) 52–137]. Retention at first follow‐up and uptake were both 80.7% (782/969 and 532/659, respectively). At enrolment, the median age was 40 (IQR 33–47) years, 95% were men who have sex with men, 47% had a university degree, and 75.5% were already taking PrEP. Most reported multiple casual partners (89.2%), previous sexually transmitted infections (74%) and sexualized drug use (73.1%). At baseline, 25.5% tested positive for either syphilis, gonorrhoea or chlamydia. Participants who dropped out were at lower risk of HIV infection than those retained after baseline assessment.

Conclusions

In a national PrEP programme using smartphone‐compatible data collection, participation, retention and uptake were high. Participants retained after baseline assessment were at considerable risk of HIV infection. Younger, less educated individuals were underrepresented in the SwissPrEPared cohort.

Integration of functional imaging in brachytherapy

Functional imaging allows the evaluation of numerous biological properties that could be considered at all steps of the therapeutic management of patients treated with brachytherapy. Indeed, it enables better initial staging of the disease, and some parameters may also be used as predictive biomarkers for treatment response, allowing better selection of patients eligible for brachytherapy. It may also improve the definition of target volumes with the aim of dose escalations by dose-painting. Finally, it could be useful during the follow-up to assess response to treatment. In this review, we report how functional imaging is integrated at the present time during the brachytherapy procedure, and what are its potential future contributions in the main tumour locations where brachytherapy is recommended. Functional imaging has great potential in the contact of brachytherapy, but still, several issues remain to be resolved before integrating it into clinical practice, especially as a biomarker or in dose painting strategies.

National Health Service interventions in England to improve care to Armed Forces veterans

Armed Forces veterans (AFVs) are first and foremost citizens of the UK and are therefore—like all UK residents—entitled to universal healthcare, free at the point of need. This means that AFVs have nearly all their healthcare needs met by the NHS, which provides access to a full range of generic services. However, since 2013 there has been an Armed Forces team that can also support veterans. This review is an assessment of the work of this group over the last eight years. The health needs of AFVs have been investigated and are not significantly different from those of their demographically matched peers. However, due to their demographics, selection at recruitment and their roles, AFVs compared with the general population are more likely to be male, white and old and have fewer pre-existing or hereditary conditions. However, they do suffer from higher rates of musculoskeletal injury, different patterns of mental health illness and have historically been higher users—and abusers—of alcohol and tobacco. In addition to supporting mainstream services used by AFVs, the NHS in England commissions a bespoke range-specific ‘Priority’ NHS services such as those for mental health or for rehabilitation of veterans using prostheses. New interventions are continuing to be developed to improve AFVs’ healthcare and are aligned to the NHS Long Term Plan and the restoration and recovery plans after the COVID-19 pandemic.

Evidence that autosomal recessive spastic cerebral palsy-1 (CPSQ1) is caused by a missense variant in HPDL

A subset of individuals diagnosed with cerebral palsy will have an underlying genetic diagnosis. Previously, a missense variant in GAD1 was described as a candidate mutation in a single family diagnosed with autosomal recessive spastic cerebral palsy-1 (CPSQ1; OMIM 603513). Following the ascertainment of a further branch of the CPSQ1 kindred, we found that the previously reported GAD1 variant did not segregate with the neurological disease phenotype in the recently ascertained branch of the kindred. Following genetic linkage studies to map autozygous regions and whole-exome sequencing, a missense variant (c.527 T > C; p. Leu176Pro, rs773333490) in the HPDL gene was detected and found to segregate with disease status in both branches of the kindred. HPDL encodes a 371-amino acid protein (4-Hydroxyphenylpyruvate Dioxygenase Like) that localizes to mitochondria but whose function is uncertain. Recently, biallelic loss of function variants and missense substitution-causing variants in HPDL were reported to cause a childhood onset progressive spastic movement disorder with a variable presentation. These findings suggest that HPDL-related neurological disease may mimic spastic cerebral palsy and that GAD1 should not be included in diagnostic gene panels for inherited cerebral palsy.

Multi O- and S-isotopes as tracers of black crusts formation under volcanic and non-volcanic atmospheric conditions in Sicily (Italy)

The deterioration of monument or building stone materials is mostly due to the growth of black crusts that cause blackening and disaggregation of the exposed surface. This study reports on new oxygen (δ¹⁷O, δ¹⁸O and Δ¹⁷O) and sulphur (δ³³S, δ³⁴S, δ³⁶S, Δ³³S and Δ³⁶S) isotopic analyses of black crust sulphates formed on building stones in Sicily (Southern Italy). The measurements are used to identify the possible influence of volcanic emissions on black crust formation. Black crusts were mostly sampled on carbonate stone substrate in different locations subject to various sulphur emission sources (marine, anthropogenic and volcanic). Unlike atmospheric sulphate aerosols that mostly exhibit Δ³³S > 0‰, here most of the analysed black crust sulphates show negative Δ³³S. This confirms that black crust sulphates do not result from deposition of sulphate aerosols or of rainwater but mostly from the oxidation of dry deposited SO₂ onto the stone substrate. The δ³⁴S and δ¹⁸O values indicate that most of black crust sulphate originates from anthropogenic activities. Δ¹⁷O values are found to be related to the sampling location. The largest ¹⁷O-anomalies (up to ~4‰) are measured in black crust from areas highly influenced by volcanic emissions, which demonstrates the strong involvement of ozone in the formation of black crusts in volcanically influenced environments.

Visual word form processing deficits driven by severity of reading impairments in children with developmental dyslexia

The visual word form area (VWFA) in the left ventral occipito-temporal (vOT) cortex is key to fluent reading in children and adults. Diminished VWFA activation during print processing tasks is a common finding in subjects with severe reading problems. Here, we report fMRI data from a multicentre study with 140 children in primary school (7.9-12.2 years; 55 children with dyslexia, 73 typical readers, 12 intermediate readers). All performed a semantic task on visually presented words and a matched control task on symbol strings. With this large group of children, including the entire spectrum from severely impaired to highly fluent readers, we aimed to clarify the association of reading fluency and left vOT activation during visual word processing. The results of this study confirm reduced word-sensitive activation within the left vOT in children with dyslexia. Interestingly, the association of reading skills and left vOT activation was especially strong and spatially extended in children with dyslexia. Thus, deficits in basic visual word form processing increase with the severity of reading disability but seem only weakly associated with fluency within the typical reading range suggesting a linear dependence of reading scores with VFWA activation only in the poorest readers.

Immune checkpoint inhibitors versus second line chemotherapy for patients with lung cancer refractory to first line chemotherapy

PURPOSE

Anti Programmed Death-ligand (PD1/PD-L1) directed immune-checkpoint-inhibitors (ICI) are widely used to treat patients with advanced non-small cell lung cancer (NSCLC) who progress after first line chemotherapy. The best strategy after early progression under first line has not been specifically studied.

PATIENTS AND METHODS

We conducted a multicenter, retrospective study including all consecutive NSCLC patients progressing within the first 3 months following introduction of first-line chemotherapy and being treated with second line ICI monotherapy or chemotherapy between March 2010 and November 2017. We analysed the clinicopathological data and outcome under second line chemotherapy vs. second line ICI: objective response rate (ORR), progression-free survival (PFS), overall survival (OS.

RESULTS

We identified 176 patients with refractory disease, 99 who received subsequent immunotherapy and 77 undergoing chemotherapy. The 2 populations were comparable regarding the main prognostic criteria, median age was 60, main histology was adenocarcimoma (68.2%). PFS was not significantly different between both treatments 1.9 [1.8-2.1] versus 1.6 month [1.4-2.0] (P=0.125). Compared to chemotherapy, ICI treated patients had a superior OS (P=0.03) (Median [95% CI] OS 4.6 [2.8-6.7] versus 4.2 months [3.4-5.9] and a non-significant improvement in ORR (17.2% versus 7.9%, respectively, P=0.072). Poor performance status (ECOG PS≥2) and a higher number of metastatic sites (≥3) were associated with poorer prognosis. KRAS-mutated patients did not seem to benefit more from ICI than chemotherapy.

CONCLUSIONS

ICI appears to be the preferred second-line treatment for patients who are refractory to first line chemotherapy.