Kanwar, Rahul

Knee osteoarthritis is one of the most common causes of chronic pain worldwide, and several animal models have been developed to investigate disease mechanisms and treatments to combat associated morbidities. Here we describe a novel method for assessment of locomotor pain behavior in Yucatan swine. We used monosodium iodoacetate (MIA) to induce osteoarthritis in the hindlimb knee, and then conducted live observation, quantitative gait analysis, and quantitative weight-bearing stance analysis. We used these methods to test the hypothesis that locomotor pain behaviors after osteoarthritis induction would be detected by multiparameter quantitation for at least 12 wk in a novel large animal model of osteoarthritis. MIA-induced knee osteoarthritis produced lameness quantifiable by all measurement techniques, with onset at 2 to 4 wk and persistence until the conclusion of the study at 12 wk. Both live observation and gait analysis of kinetic parameters identified mild and moderate osteoarthritis phenotypes corresponding to a binary dose relationship. Quantitative stance analysis demonstrated the greatest sensitivity, discriminating between mild osteoarthritis states induced by 1.2 and 4.0 mg MIA, with stability of expression for as long as 12 wk. The multiparameter quantitation used in our study allowed rejection of the null hypothesis. This large animal model of quantitative locomotor pain resulting from MIA-induced osteoarthritis may support the assessment of new analgesic strategies for human knee osteoarthritis.

AbstractPaclitaxel‐induced peripheral neuropathy (PIPN) cannot be predicted from clinical parameters and might have a pharmacogenomic basis. Previous studies identified single nucleotide variants (SNV) associated with PIPN. However, only a subset of findings has been confirmed to date in more than one study, suggesting a need for further re‐testing and validation in additional clinical cohorts. Candidate PIPN‐associated SNVs were identified from the literature. SNVs were retested in 119 patients selected by extreme phenotyping from 269 in NCCTG N08C1 (Alliance) as previously reported. SNV genotyping was performed by a combination of short‐read sequencing analysis and Taqman PCR. These 22 candidate PIPN SNVs were genotyped. Two of these, rs7349683 in the EPHA5 and rs3213619 in ABCB1 were found to be significantly associated with PIPN with an Odds ratios OR = 2.07 (P = 0.02) and OR = 0.12 (P = 0.03), respectively. In addition, three SNVs showed a trend toward a risk‐ or protective effect that was consistent with previous reports. The rs10509681 and rs11572080 in the gene CYP2C8*3 showed risk effect with an OR = 1.49 and rs1056836 in CYP1B1 showed a protective effect with an OR = 0.66. None of the other results supported the previously reported associations, including some SNVs displaying an opposite direction of effect from previous reports, including rs1058930 in CYP2C8, rs17222723 and rs8187710 in ABCC2, rs10771973 in FGD4, rs16916932 in CACNB2 and rs16948748 in PITPNA. Alliance N08C1 validated or supported a minority of previously reported SNV‐PIPN associations. Associations previously reported by multiple studies appeared to have a higher likelihood to be validated by Alliance N08C1.

ObjectiveMutations in Charcot–Marie–Tooth disease (CMT) genes are the cause of rare familial forms of polyneuropathy. Whether allelic variability in CMT genes is also associated with common forms of polyneuropathy—considered “acquired” in medical parlance—is unknown. Chemotherapy‐induced peripheral neuropathy (CIPN) occurs commonly in cancer patients and is individually unpredictable. We used CIPN as a clinical model to investigate the association of non‐CMT polyneuropathy with CMT genes.MethodsA total of 269 neurologically asymptomatic cancer patients were enrolled in the clinical trial Alliance N08C1 to receive the neurotoxic drug paclitaxel, while undergoing prospective assessments for polyneuropathy. Forty‐nine CMT genes were analyzed by targeted massively parallel sequencing of genomic DNA from patient blood.ResultsA total of 119 (of 269) patients were identified from the 2 ends of the polyneuropathy phenotype distribution: patients that were most and least susceptible to paclitaxel polyneuropathy. The CMT gene PRX was found to be deleteriously mutated in patients who were susceptible to CIPN but not in controls (p = 8 × 10−3). Genetic variation in another CMT gene, ARHGEF10, was highly significantly associated with CIPN (p = 5 × 10−4). Three nonsynonymous recurrent single nucleotide variants contributed to the ARHGEF10 signal: rs9657362, rs2294039, and rs17683288. Of these, rs9657362 had the strongest effect (odds ratio = 4.8, p = 4 × 10−4).InterpretationThe results reveal an association of CMT gene allelic variability with susceptibility to CIPN. The findings raise the possibility that other acquired polyneuropathies may also be codetermined by genetic etiological factors, of which some may be related to genes already known to cause the phenotypically related Mendelian disorders of CMT. Ann Neurol 2014;76:727–737

Abstract Introduction: Symptom control is an important objective in the care of patients with cancer and a critical goal for long-term survivors of antineoplastic treatments. Commonly used chemotherapies, including paclitaxel, are associated with a toxic effect on the peripheral nervous system in a substantial fraction of patients, termed chemotherapy induced peripheral neuropathy (CIPN), that is often debilitating. CIPN cannot be predicted from clinical parameters in neurologically normal subjects, suggesting a genetic basis as the root cause. Patients with hereditary neuropathy (HN) due to one of ~50 recognized genes are prone to developing severe CIPN even if the hereditary predisposition is clinically silent. Assessment of CIPN has usually been an afterthought of cancer treatment studies using crude symptom measurement instruments. N08C1 and N08CA are recent clinical trials_the latter analyzed only in early 2013_focusing on extensive phenotyping by patient reported outcomes (PRO) to support genetic investigations of paclitaxel-related CIPN. Massively parallel (“nextgen”) DNA sequencing is the genetic technology of choice and represents an as-yet unrealized potential to study cancer symptom control. Methods: Exome sequencing_analysis of 20,794 genes at nucleotide resolution_was performed on blood of CIPN cases (n=73) and controls (n=46) from N08C1. The primary endpoint was the association of HN genes with CIPN. Bioinformatic analysis determined SNV and other genetic variations across 6.2x107 nucleotides. The association of genes with CIPN was statistically examined by the over-dispersion test C-alpha. The role of singleton SNV was assessed by a burden test. N08CA served as validation. Results: 386,644 SNV were detected with an estimated sensitivity of 90% and specificity of 99.9%; the orthogonal validation rate (PCR of >1000 genotypes) was 99.7%. The association of the minor allele (C>T) at rs7349683 in the gene EPHA5, previously reported by Baldwin et al. (2012) for CALGB40101, was confirmed in N08C1. Two hereditary neuropathy genes were identified as new CIPN candidate genes: Firstly, ARHGEF10 was highly significant with p=5x10-4 based on single gene testing and p<0.02 after Bonferroni correction for multiple testing of 41 hereditary neuropathy genes with non-synonymous SNV. Three SNV were predictive, rs17683288, rs2294039 and rs9657362, the latter with an odds ratio (OR)=3.62. Validation in an independent patient group (n=75) from another paclitaxel CIPN trial, N08CA, confirmed the impact of ARHGEF10 on CIPN (p<0.025; rs9657362 OR=2.51). Secondly, peraxin (PRX) was disrupted by non-synonymous singleton SNV in n=8 cases and n=0 controls (OR=6.4; unadjusted p=0.04). 7 of the 8 mutations were also scored as deleterious by both Polyphen 2 and SIFT. Because PRX SNV were non-recurrent validation was performed in N08C1 by Sanger sequencing. Several neuro-genes across the exome were noted as additional CIPN gene candidates. Conclusions: ARHGEF10 and PRX associations with CIPN suggest that CIPN and HN might share genetic roots in a subset of patients. Construct validity of N08C1 is supported by confirmation of a published result from CALGB40101 relating EPHA5 to CIPN. Germline exome sequencing in cancer patients is highly informative for understanding complex pharmacogenomic traits including outcomes in symptom control research. Citation Format: Andreas S. Beutler, Amit Kulkarni, Rahul Kanwar, Rui Qin, Julie M. Cunningham, Terry M. Therneau, Charles L. Loprinzi. Sequencing symptom control: Results from the Alliance N08C1 and N08CA genetics of chemotherapy neuropathy trials. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-196. doi:10.1158/1538-7445.AM2013-LB-196

Abstract Summary: Reduced representation bisulfite sequencing (RRBS) is a cost-effective approach for genome-wide methylation pattern profiling. Analyzing RRBS sequencing data is challenging and specialized alignment/mapping programs are needed. Although such programs have been developed, a comprehensive solution that provides researchers with good quality and analyzable data is still lacking. To address this need, we have developed a Streamlined Analysis and Annotation Pipeline for RRBS data (SAAP-RRBS) that integrates read quality assessment/clean-up, alignment, methylation data extraction, annotation, reporting and visualization. This package facilitates a rapid transition from sequencing reads to a fully annotated CpG methylation report to biological interpretation. Availability and implementation: SAAP-RRBS is freely available to non-commercial users at the web site http://ndc.mayo.edu/mayo/research/biostat/stand-alone-packages.cfm. Contact: baheti.saurabh@mayo.edu or sun.zhifu@mayo.edu Supplementary Information: Supplementary data are available at Bioinformatics online.