Effects of eight neuropsychiatric copy number variants on human brain structure

Many copy number variants (CNVs) confer risk for the same range of neurodevelopmental symptoms and psychiatric conditions including autism and schizophrenia. Yet, to date neuroimaging studies have typically been carried out one mutation at a time, showing that CNVs have large effects on brain anatomy. Here, we aimed to characterize and quantify the distinct brain morphometry effects and latent dimensions across 8 neuropsychiatric CNVs. We analyzed T1-weighted MRI data from clinically and non-clinically ascertained CNV carriers (deletion/duplication) at the 1q21.1 (n = 39/28), 16p11.2 (n = 87/78), 22q11.2 (n = 75/30), and 15q11.2 (n = 72/76) loci as well as 1296 non-carriers (controls). Case-control contrasts of all examined genomic loci demonstrated effects on brain anatomy, with deletions and duplications showing mirror effects at the global and regional levels. Although CNVs mainly showed distinct brain patterns, principal component analysis (PCA) loaded subsets of CNVs on two latent brain dimensions, which explained 32 and 29% of the variance of the 8 Cohen’s d maps. The cingulate gyrus, insula, supplementary motor cortex, and cerebellum were identified by PCA and multi-view pattern learning as top regions contributing to latent dimension shared across subsets of CNVs. The large proportion of distinct CNV effects on brain morphology may explain the small neuroimaging effect sizes reported in polygenic psychiatric conditions. Nevertheless, latent gene brain morphology dimensions will help subgroup the rapidly expanding landscape of neuropsychiatric variants and dissect the heterogeneity of idiopathic conditions

Régulation de l'expression des gènes précoces, des neuropepetides et des neurotransmetteurs dans le cortex cérébral et dans le striatum suite à des lésions du cortex cérébral

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Régulation de l'expression des gènes précoces, des neuropepetides et des neurotransmetteurs dans le cortex cérébral et dans le striatum suite à des lésions du cortex cérébral

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Changes in striatal neuropeptides and GAD67 expression following a minimal cortical lesion.

We have analyzed the effects of a small cortical infarct which is known to induce dramatic changes in gene expression in the entire cerebral cortex, on the gene expression in the striatum, a target structure of cortical neurons. Striatal glutamic acid decarboxylase (GAD67) and enkephalin expressions were increased in the striatum ipsilateral to the lesion. Conversely, neuropeptide Y- and somatostatin-like immunoreactivity were decreased in the ipsilateral striatum and this decrease was only related to a decrease in the labeling of processes with no changes in the number of labeled neurons. A minimal cortical lesion may therefore induce changes in gene expression in a subcortical structure through hyperactivity of glutamatergic synaptic inputs. One should therefore remember these extensive and long-lasting effects when surgical manipulations are performed on rat brain for stereotaxic surgery and placement of electrodes or probes.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

NMDA receptor antagonist MK-801 down-regulates rat striatal proenkephalin and protachykinin mRNAs

Using quantitative in situ hybridization, a significant decrease in expression of proenkephalin (27.1%) and of protachykinin (27.1%) and of protachykinin mRNAs (20.0%) is observed in the rat caudate-putamen 14 days after daily intraperitoneal administration of N-methyl-D-aspartate receptor antagonist MK-801, 2 mg/kg.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Homolateral cerebrocortical changes in neuropeptide and receptor expression after minimal cortical infarction.

A cortical infarct of 2 mm diameter was obtained in the parietal cortex after a craniotomy, disruption of the dura mater and topical application of 3 M KCl. It has been shown previously that the presence of a small cortical infarct induces an increase in immediate early gene messenger RNA expression followed by an increase in neuropeptide and glutamic acid decarboxylase messenger RNA expression. Glutamate, acting at N-methyl-D-aspartate receptors, is held responsible for these changes, since they are blocked by pretreatment with dizocilpine. In the present study, we have analysed the consequences of the dramatic changes in messenger RNA expression on the level of immediate early gene products c-fos and zif 268, and on that of neuropeptides by using immunohistochemistry. After just 1 h, an increase in c-fos- and zif 268-like immunoreactivity is observed in the entire cortical hemisphere homolateral to the infarct, and is no longer detected after 6 h. An increase in cholecystokinin octapeptide-, substance P-, neuropeptide Y- and somatostatin-like immunoreactivity is observed in the entire cortical hemisphere homolateral to the infarct after three days, and is no longer detected after 30 days. To investigate if these dramatic increases in neuropeptide immunoreactivities may have functional consequences, we studied the level of cholecystokinin receptors by autoradiographic binding using [125I]cholecystokinin-8S and in situ hybridization for the detection of cholecystokinin-b receptor messenger RNA. A decrease in cholecystokinin binding sites and cholecystokinin-b receptor messenger RNA is observed in the entire cortical hemisphere homolateral to the infarct after three days, and is no longer detected after nine days. This study shows that a topical stimulation has diffuse effects, reaching regions far from the site of the lesion, and some of them are still strongly present after nine days. The increase in neuropeptide messenger RNAs is followed by an increase in the protein products of these genes, which may modify the neurotransmission. As a corollary to this, a decrease in cholecystokinin binding sites occurs. This may have further consequences on signal transduction pathways. This decrease in cholecystokinin binding sites is associated with a decrease in the cholecystokinin-b receptor messenger RNA, and this is the first example of a decrease in messenger RNA levels in this experimental model.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Pharmacokinetic–pharmacodynamic guided optimisation of dose and schedule of CGM097, an HDM2 inhibitor, in preclinical and clinical studies

Background: CGM097 inhibits the p53-HDM2 interaction leading to downstream p53 activation. Preclinical in vivo studies support clinical exploration while providing preliminary evidence for dosing regimens. This first-in-human phase I study aimed at assessing the safety, MTD, PK/PD and preliminary antitumor activity of CGM097 in advanced solid tumour patients (NCT01760525). Methods: Fifty-one patients received oral treatment with CGM097 10-400 mg 3qw (n = 31) or 300-700 mg 3qw 2 weeks on/1 week off (n = 20). Choice of dose regimen was guided by PD biomarkers, and quantitative models describing the effect of CGM097 on circulating platelet and PD kinetics. Results: No dose-limiting toxicities were reported in any regimens. The most common treatment-related grade 3/4 AEs were haematologic events. PK/PD models well described the time course of platelet and serum GDF-15 changes, providing a tool to predict response to CGM097 for dose-limiting thrombocytopenia and GDF-15 biomarker. The disease control rate was 39%, including one partial response and 19 patients in stable disease. Twenty patients had a cumulative treatment duration of >16 weeks, with eight patients on treatment for >32 weeks. The MTD was not determined. Conclusions: Despite delayed-onset thrombocytopenia frequently observed, the tolerability of CGM097 appears manageable. This study provided insights on dosing optimisation for next-generation HDM2 inhibitors. Translational relevance: Haematologic toxicity with delayed thrombocytopenia is a well-known on-target effect of HDM2 inhibitors. Here we have developed a PK/PD guided approach to optimise the dose and schedule of CGM097, a novel HDM2 inhibitor, using exposure, platelets and GDF-15, a known p53 downstream target to predict patients at higher risk to develop thrombocytopenia. While CGM097 had shown limited activity, with disease control rate of 39% and only one patient in partial response, the preliminary data from the first-in-human escalation study together with the PK/PD modeling provide important insights on how to optimize dosing of next generation HDM2 inhibitors to mitigate hematologic toxicity

Quantification of 18F-fluorodeoxyglucose uptake to detect residual nodal disease in locally advanced head and neck squamous cell carcinoma after chemoradiotherapy: results from the ECLYPS study

BACKGROUND: The Hopkins criteria were introduced for nodal response evaluation after therapy in head and neck cancer, but its superiority over quantification is not yet confirmed. METHODS: SUVbody weight thresholds and lesion-to-background ratios were explored in a prospective multicenter study of standardized FDG-PET/CT 12 weeks after CRT in newly diagnosed locally advanced head and neck squamous cell carcinoma (LAHNSCC) patients (ECLYPS). Reference standard was histology, negative FDG-PET/CT at 12 months after treatment or ≥ 2 years of negative follow-up. Area under the receiver operator characteristics curves (AUROC) were estimated and obtained thresholds were validated in an independent cohort of HNSCC patients (n = 127). RESULTS: In ECLYPS, 124 patients were available for quantification. With a median follow-up of 20.4 months, 23 (18.5%) nodal neck recurrences were observed. A SUV70 threshold of 2.2 (AUROC = 0.89; sensitivity = 79.7%; specificity = 80.8%) was identified as optimal metric to identify nodal recurrence within 1 year after therapy. For lesion-to-background ratios, an SUV50/SUVliver threshold of 0.96 (AUROC = 0.89; sensitivity = 79.7%; specificity = 82.8%) had the best performance. Compared with Hopkins criteria (AUROC = 0.81), SUV70 and SUV50/SUVliver provided a borderline significant (p = 0.040 and p = 0.094, respectively) improvement. Validation of thresholds yielded similar AUROC values (SUV70 = 0.93, SUV50/SUVliver = 0.95), and were comparable to the Hopkins score (AUROC = 0.91; not statistically significant). CONCLUSION: FDG quantification detects nodal relapse in LAHNSCC patients. When using EARL standardized PET acquisitions and reconstruction, absolute SUV metrics (SUV70 threshold 2.2) prove robust, yet ratios (SUV50/SUVliver, threshold 0.96) may be more useful in routine clinical care. In this setting, the diagnostic value of quantification is comparable to the Hopkins criteria. TRIAL REGISTRATION: US National Library for Medicine, NCT01179360. Registered 11 August 2010, https://clinicaltrials.gov/ct2/show/NCT01179360

Quantification of 18F-fluorodeoxyglucose uptake to detect residual nodal disease in locally advanced head and neck squamous cell carcinoma after chemoradiotherapy: results from the ECLYPS study

BACKGROUND: The Hopkins criteria were introduced for nodal response evaluation after therapy in head and neck cancer, but its superiority over quantification is not yet confirmed. METHODS: SUVbody weight thresholds and lesion-to-background ratios were explored in a prospective multicenter study of standardized FDG-PET/CT 12 weeks after CRT in newly diagnosed locally advanced head and neck squamous cell carcinoma (LAHNSCC) patients (ECLYPS). Reference standard was histology, negative FDG-PET/CT at 12 months after treatment or ≥ 2 years of negative follow-up. Area under the receiver operator characteristics curves (AUROC) were estimated and obtained thresholds were validated in an independent cohort of HNSCC patients (n = 127). RESULTS: In ECLYPS, 124 patients were available for quantification. With a median follow-up of 20.4 months, 23 (18.5%) nodal neck recurrences were observed. A SUV70 threshold of 2.2 (AUROC = 0.89; sensitivity = 79.7%; specificity = 80.8%) was identified as optimal metric to identify nodal recurrence within 1 year after therapy. For lesion-to-background ratios, an SUV50/SUVliver threshold of 0.96 (AUROC = 0.89; sensitivity = 79.7%; specificity = 82.8%) had the best performance. Compared with Hopkins criteria (AUROC = 0.81), SUV70 and SUV50/SUVliver provided a borderline significant (p = 0.040 and p = 0.094, respectively) improvement. Validation of thresholds yielded similar AUROC values (SUV70 = 0.93, SUV50/SUVliver = 0.95), and were comparable to the Hopkins score (AUROC = 0.91; not statistically significant). CONCLUSION: FDG quantification detects nodal relapse in LAHNSCC patients. When using EARL standardized PET acquisitions and reconstruction, absolute SUV metrics (SUV70 threshold 2.2) prove robust, yet ratios (SUV50/SUVliver, threshold 0.96) may be more useful in routine clinical care. In this setting, the diagnostic value of quantification is comparable to the Hopkins criteria. TRIAL REGISTRATION: US National Library for Medicine, NCT01179360. Registered 11 August 2010, https://clinicaltrials.gov/ct2/show/NCT01179360.status: publishe