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Kerstin Kutsche and colleagues report that mutations in GRIN2A and GRIN2B cause variable neurodevelopmental phenotypes including mental retardation and epilepsy. GRIN2A and GRIN2B encode regulatory subunits of N-methyl-D-aspartate (NMDA) receptors, which mediate excitatory neurotransmission in the brain. N-methyl-D-aspartate (NMDA) receptors mediate excitatory neurotransmission in the mammalian brain. Two glycine-binding NR1 subunits and two glutamate-binding NR2 subunits each form highly Ca 2+ -permeable cation channels which are blocked by extracellular Mg 2+ in a voltage-dependent manner 1 . Either GRIN2B or GRIN2A , encoding the NMDA receptor subunits NR2B and NR2A, was found to be disrupted by chromosome translocation breakpoints in individuals with mental retardation and/or epilepsy. Sequencing of GRIN2B in 468 individuals with mental retardation revealed four de novo mutations: a frameshift, a missense and two splice-site mutations. In another cohort of 127 individuals with idiopathic epilepsy and/or mental retardation, we discovered a GRIN2A nonsense mutation in a three-generation family. In a girl with early-onset epileptic encephalopathy, we identified the de novo GRIN2A mutation c.1845C>A predicting the amino acid substitution p.N615K. Analysis of NR1-NR2A N615K (NR2A subunit with the p.N615K alteration) receptor currents revealed a loss of the Mg 2+ block and a decrease in Ca 2+ permeability. Our findings suggest that disturbances in the neuronal electrophysiological balance during development result in variable neurological phenotypes depending on which NR2 subunit of NMDA receptors is affected.

The adaptor molecule stimulator of IFN genes (STING) is central to production of type I IFNs in response to infection with DNA viruses and to presence of host DNA in the cytosol. Excessive release of type I IFNs through STING-dependent mechanisms has emerged as a central driver of several interferonopathies, including systemic lupus erythematosus (SLE), Aicardi–Goutières syndrome (AGS), and stimulator of IFN genes-associated vasculopathy with onset in infancy (SAVI). The involvement of STING in these diseases points to an unmet need for the development of agents that inhibit STING signaling. Here, we report that endogenously formed nitro-fatty acids can covalently modify STING by nitro-alkylation. These nitro-alkylations inhibit STING palmitoylation, STING signaling, and subsequently, the release of type I IFN in both human and murine cells. Furthermore, treatment with nitro-fatty acids was sufficient to inhibit production of type I IFN in fibroblasts derived from SAVI patients with a gain-of-function mutation in STING. In conclusion, we have identified nitro-fatty acids as endogenously formed inhibitors of STING signaling and propose for these lipids to be considered in the treatment of STING-dependent inflammatory diseases.

Bortezomib-induced peripheral neuropathy is a dose-limiting toxicity in patients with multiple myeloma, often requiring adjustment of treatment and affecting quality of life. We investigated the molecular profiles of early-onset (within one treatment cycle) versus late-onset (after two or three treatment cycles) bortezomib-induced peripheral neuropathy and compared them with those of vincristine-induced peripheral neuropathy during the induction phase of a prospective phase 3 trial. In the induction phase of the HOVON-65/GMMG-HD4 trial, patients (aged 18–65 years) with newly diagnosed Salmon and Durie stage 2 or 3 multiple myeloma were randomly assigned to three cycles of bortezomib-based or vincristine-based induction treatment. We analysed the gene expression profiles and single-nucleotide polymorphisms (SNPs) of pretreatment samples of myeloma plasma cells and peripheral blood, respectively. This study is registered, number ISRCTN64455289. We analysed gene expression profiles of myeloma plasma cells from 329 (39%) of 833 patients at diagnosis, and SNPs in DNA samples from 369 (44%) patients. Early-onset bortezomib-induced peripheral neuropathy was noted in 20 (8%) patients, and 63 (25%) developed the late-onset type. Early-onset and late-onset vincristine-induced peripheral neuropathy was noted in 11 (4%) and 17 (7%) patients, respectively. Significant genes in myeloma plasma cells from patients that were associated with early-onset bortezomib-induced peripheral neuropathy were the enzyme coding genes RHOBTB2 (upregulated by 1·59 times; p=4·5×10 −5), involved in drug-induced apoptosis, CPT1C (1·44 times; p=2·9×10 −7), involved in mitochondrial dysfunction, and SOX8 (1·68 times; p=4·28×10 −13), involved in development of peripheral nervous system. Significant SNPs in the same patients included those located in the apoptosis gene caspase 9 (odds ratio [OR] 3·59, 95% CI 1·59–8·14; p=2·9×10 −3), ALOX12 (3·50, 1·47–8·32; p=3·8×10 −3), and IGF1R (0·22, 0·07–0·77; p=8·3×10 −3). In late-onset bortezomib-induced peripheral neuropathy, the significant genes were SOD2 (upregulated by 1·18 times; p=9·6×10 −3) and MYO5A (1·93 times; p=3·2×10 −2), involved in development and function of the nervous system. Significant SNPs were noted in inflammatory genes MBL2 (OR 0·49, 95% CI 0·26–0·94; p=3·0×10 −2) and PPARD (0·35, 0·15–0·83; p=9·1×10 −3), and DNA repair genes ERCC4 (2·74, 1·56–4·84; p=1·0×10 −3) and ERCC3 (1·26, 0·75–2·12; p=3·3×10 −3). By contrast, early-onset vincristine-induced peripheral neuropathy was characterised by upregulation of genes involved in cell cycle and proliferation, including AURKA (3·31 times; p=1·04×10 −2) and MKI67 (3·66 times; p=1·82×10 −3), and the presence of SNPs in genes involved in these processes—eg, GLI1 (rs2228224 [0·13, 0·02–0·97, p=1·18×10 −2] and rs2242578 [0·14, 0·02–1·12, p=3·00×10 −2]). Late-onset vincristine-induced peripheral neuropathy was associated with the presence of SNPs in genes involved in absorption, distribution, metabolism, and excretion—eg, rs1413239 in DPYD (3·29, 1·47–7·37, 5·40×10 −3) and rs3887412 in ABCC1 (3·36, 1·47–7·67, p=5·70×10 −3). Our results strongly suggest an interaction between myeloma-related factors and the patient's genetic background in the development of treatment-induced peripheral neuropathy, with different molecular pathways being implicated in bortezomib-induced and vincristine-induced peripheral neuropathy. German Federal Ministry of Education and Research, Dutch Cancer Foundation Queen Wilhelmina, European Hematology Association, International Myeloma Foundation, Erasmus MC, and Janssen-Cilag Orthobiotech.

Vincristine-induced peripheral neuropathy (VIPN) is an adverse effect of regimens used for the treatment of aggressive B-cell non-Hodgkin lymphoma (B-NHL). A single-nucleotide polymorphism (SNP) in the promotor region of the CEP72 gene has been identified as risk factor for the development of VIPN in children. To validate these results in adults we aimed to determine the association of the high-risk CEP72 (rs924607 TT genotype) with the occurrence and severity of VIPN. Analysis of SNP rs924607 (TT, CC or CT) was performed in all enrolled patients with available blood samples with a TaqMan genotyping assay. Rates and grades of VIPN were assessed prospectively as part of the RICOVER-60 trial. CEP72 genotype could be assessed in 519 patients. VIPN data was available for 499/519 patients who were included in the final analysis. 286 (57%) patients developed VIPN of any grade during treatment. Grade 2–4 VIPN occurred in 33% (166/499) of patients. The high-risk CEP72 TT genotype at rs924607 was identified in 97/499 (19%) patients. The TT genotype was not correlated with VIPN in the overall study population compared to patients with either CC or CT genotypes (p = 0.748). However, in the subgroup of female patients, the TT genotype was associated with increased occurrence of any-grade VIPN as well as grade 2–4 VIPN as compared to patients with either CC or CT genotypes (p = 0.016 and p = 0.020, respectively). Thus, the SNP rs924607 in the CEP72 gene is associated with increased VIPN incidence in female patients with aggressive B-NHL treated with CHOP chemotherapy. Trial registration ClinicalTrials.gov identifier: NCT00052936, submission date: 2005-06-23, EudraCT Number: 2010-019587-36.

An ongoing challenge in children presenting with motor delay/impairment early in life is to identify neurogenetic disorders with a clinical phenotype, which can be misdiagnosed as cerebral palsy (CP). To help distinguish patients in these two groups, conventional magnetic resonance imaging of the brain has been of great benefit in “unmasking” many of these genetic etiologies and has provided important clues to differential diagnosis in others. Recent advances in molecular genetics such as chromosomal microarray and next-generation sequencing have further revolutionized the understanding of etiology by more precisely classifying these disorders with a molecular cause. In this paper, we present a review of neurogenetic disorders masquerading as cerebral palsy evaluated at one institution. We have included representative case examples children presenting with dyskinetic, spastic, and ataxic phenotypes, with the intent to highlight the time-honored approach of using clinical tools of history and examination to focus the subsequent etiologic search with advanced neuroimaging modalities and molecular genetic tools. A precise diagnosis of these masqueraders and their differentiation from CP is important in terms of therapy, prognosis, and family counseling. In summary, this review serves as a continued call to remain vigilant for current and other to-be-discovered neurogenetic masqueraders of cerebral palsy, thereby optimizing care for patients and their families.

Background Oxaliplatin is a chemotherapy agent active against digestive tumors. Peripheral neuropathy is one of the most important dose-limiting toxicity of this drug. It occurs in around 60–80% of the patients, and 15% of them develop severe neuropathy. The pathophysiology of oxaliplatin neurotoxicity remains unclear. SCN9A is a gene codifying for a subtype sodium channel (type IX, subunit α) and mutations in this gene are involved in neuropathic perception. In this study we investigated whether SCN9A genetic variants were associated with risk of neurotoxicity in patients diagnosed of cancer on treatment with oxaliplatin. Methods Blood samples from 94 patients diagnosed of digestive cancer that had received oxaliplatin in adjuvant or metastatic setting were obtained from three hospitals in Madrid. These patients were classified into two groups: “cases” developed oxaliplatin-induced grade 3–4 neuropathy ( n  = 48), and “controls” ( n  = 46) had no neuropathy or grade 1. The neuropathy was evaluated by an expert neurologist and included a clinical examination and classification according to validated neurological scales: National Cancer Institute Common Toxicity Criteria ( NCI-CTC ), Oxaliplatin-Specific Neurotoxicity Scale (OSNS ) and Total Neuropathy score (TNS ). Genotyping was performed for 3 SCN9A missense polymorphisms: rs6746030 (R1150W), rs74401238 (R1110Q) and rs41268673 (P610T), and associations between genotypes and neuropathy were evaluated. Results We found that SCN9A rs6746030 was associated with protection for severe neuropathy (OR = 0.39, 95% CI = 0.16–0.96; p  = 0.041). Multivariate analysis adjusting for diabetes provided similar results ( p  = 0.036). No significant differences in neuropathy risk were detected for rs74401238 and rs41268673. Conclusion SCN9A rs6746030 was associated with protection for severe oxaliplatin-induced peripheral neuropathy. The validation of this exploratory study is ongoing in an independent series.

Background Chemotherapy-induced peripheral neuropathy (CIPN) is a common toxicity of taxanes for which there is no effective intervention. Genomic CIPN risk determination has yielded promising, but inconsistent results. The present study assessed the utility of a collective SNP cluster identified using novel analytics to describe taxane-associated CIPN risk. Methods We analyzed GWAS data derived from ECOG-5103, first identifying SNPs that were most strongly associated with CIPN using Fisher’s ratio (FR). We then ranked ordered those SNPs which discriminated CIPN-positive (CIPN +) from CIPN-negative phenotypes based on their discriminatory power and developed the cluster of SNPs which provided the highest predictive accuracy using leave-one-out cross-validation (LOOCV). Results Using aggregated genotype data obtained from the previously reported ECOG-5103 clinical trial (in which two different arrays were used, HumanOmniExpress (727,227 SNPs) and HumanOmni1-Quad1 (1,131,857 SNPs)), we identified a 267 SNP cluster which was associated with a CIPN + phenotype with an accuracy of 96.1%. Conclusions A cluster of SNPs was identified which prospectively discriminated patients most likely to develop symptomatic CIPN following taxane exposure as part of a breast cancer chemotherapy regimen. Validation using an independent patient cohort should be performed.

Background: The purpose of this study was to evaluate single-nucleotide polymorphisms (SNPs) in genes encoding key metabolising enzymes or involved in pharmacodynamics for possible associations with paclitaxel-induced peripheral neuropathy. Methods: The study population consists of 188 women from the multicenter, randomised, phase II ATX trial (BOOG2006-06; EudraCT number 2006-006058-83) that received paclitaxel and bevacizumab without or with capecitabine as first-line palliative therapy of HER2-negative metastatic breast cancer. Genotyping of CYP2C8 *3 (c.416G>A), CYP3A4 *22 (c.522-191C>T), TUBB2A (c.-101T>C), FGD4 (c.2044-236G>A) and EPHA5 (c.2895G>A) was performed by real-time PCR. Toxicity endpoints were cumulative dose (1) until first onset of grade ⩾1 peripheral neuropathy and (2) until first paclitaxel dose reduction from related toxicity (NCI-CTCAE version 3.0). SNPs were evaluated using the Kaplan–Meier method, the Gehan–Breslow–Wilcoxon test and the multivariate Cox regression analysis. Results: The rate of grade ⩾1 peripheral neuropathy was 67% ( n =126). The rate of dose reduction was 46% ( n =87). Age ⩾65 years was a risk factor for peripheral neuropathy (HR=1.87, P <0.008), but not for dose reduction. When adjusted for age, body surface area and total cumulative paclitaxel dose, CYP2C8 *3 carriers had an increased risk of peripheral neuropathy (HR=1.59, P =0.045). FGD4 c.2044-236 A-allele carriers had an increased risk of paclitaxel dose reduction (HR per A-allele=1.38, P =0.036) when adjusted for total cumulative paclitaxel dose. Conclusions: These findings may point towards clinically useful indicators of early toxicity, but warrant further investigation.