Time-intensity curves obtained after microbubble injection can be used to differentiate responders from nonresponders among patients with clinically active Crohn disease after 6 weeks of pharmacologic treatment

Purpose: To assess whether contrast material-enhanced ultrasonography (US) can be used to differentiate responders from nonresponders among patients with clinically active Crohn disease after\ub1weeks of pharmacologic treatment. Materials and Methods: This prospective study was approved by our ethics committee, and written informed consent was obtained from all patients. Fifty consecutive patients (26 men and 24 women; mean age, 34.76 years\ub19) with a proved diagnosis of active Crohn disease who were scheduled to begin therapy with biologics (infliximab or adalimumab) were included, with enrollment from June 1, 2013, to June 1, 2015. In each patient, the terminal ileal loop was imaged with contrast-enhanced US before the beginning and at the end of week\ub1of pharmacologic treatment. Time-intensity curves obtained in responders (those with a decrease in the Crohn disease endoscopic index of severity score of 25-44 before treatment to 10-15 after treatment, an inflammatory score ,7, and/or a decrease 6570 in the Crohn disease activity index score compared with baseline) and nonresponders were compared with Mann-Whitney test. Results: Responders (n = 31) and nonresponders (n = 19) differed (P , .05) in the percent change of peak enhancement (240.78\ub162.85 vs 53.21\ub172.5; P = .0001), wash-in (234.8\ub167.72 vs 89.44\ub1145.32; P = .001) and washout (25.64\ub1130.71 vs 166.83\ub1204.44; P = .002) rate, wash-in perfusion index (242.29\ub159.21 vs 50.96\ub171.13; P = .001), area under the time-intensity curve (AUC; 246.17\ub148.42 vs 41.78\ub187.64; P = .001), AUC during wash-in (243.93\ub154.29 vs 39.79\ub170.85; P = .001), and AUC during washout (249.36\ub147.42 vs 42.65\ub197.09; P = .001). Responders and nonresponders did not differ in the percent change of rise time (5.09\ub149.13 vs 6.24\ub148.06; P = .93) and time to peak enhancement (8.82\ub154.5 vs 10.21\ub143.25; P = .3). Conclusion: Analysis of time-intensity curves obtained after injection of microbubble contrast material\ub1weeks after beginning pharmacologic treatment can be used to differentiate responders from nonresponders among patients with clinically active Crohn disease

Toward a better definition of EPCAM deletions in Lynch Syndrome: Report of new variants in Italy and the associated molecular phenotype

BackgroundInherited epimutations of Mismatch Repair (MMR) genes are responsible for Lynch Syndrome (LS) in a small, but well defined, subset of patients. Methylation of the MSH2 promoter consequent to the deletion of the upstream EPCAM gene is found in about 1%-3% of the LS patients and represents a classical secondary, constitutional and tissue-specific epimutation. Several different EPCAM deletions have been reported worldwide, for the most part representing private variants caused by an Alu-mediated recombination.Methods712 patients with suspected LS were tested for MMR mutation in our Institute. EPCAM deletions were detected by multiplex ligation-dependent probe amplification (MLPA) and then defined by Long-Range polymerase chain reaction (PCR)/Sanger sequencing. A comprehensive molecular characterization of colorectal cancer (CRC) tissues was carried out by immunohistochemistry of MMR proteins, Microsatellite Instability (MSI) assay, methylation specific MLPA and transcript analyses. In addition, somatic deletions and/or variants were investigated by MLPA and next generation sequencing (NGS).ResultsAn EPCAM deletion was found in five unrelated probands in Italy: variants c.556-490_*8438del and c.858+1193_*5826del are novel; c.859-1430_*2033del and c.859-670_*530del were previously reported. All probands were affected by CRC at young age; tumors showed MSI and abnormal MSH2/MSH6 proteins expression. MSH2 promoter methylation, as well as aberrant in-frame or out-of-frame EPCAM/MSH2 fusion transcripts, were detected in CRCs and normal mucosae.ConclusionAn EPCAM deletion was the causative variant in about 2% of our institutional series of 224 LS patients, consistent with previously estimated frequencies. Early age and multiple CRCs was the main clinical feature of this subset of patients

Loss of MUTYH function in human cells leads to accumulation of oxidative damage and genetic instability

The DNA glycosylase MUTYH (mutY homolog (Escherichia coli)) counteracts the mutagenic effects of 8-oxo-7,8-dihydroguanine (8-oxodG) by removing adenine (A) misincorporated opposite the oxidized purine. Biallelic germline mutations in MUTYH cause the autosomal recessive MUTYH-associated adenomatous polyposis (MAP). Here we designed new tools to investigate the biochemical defects and biological consequences associated with different MUTYH mutations in human cells. To identify phenotype(s) associated with MUTYH mutations, lymphoblastoid cell lines (LCLs) were derived from seven MAP patients harboring missense as well as truncating mutations in MUTYH. These included homozygous p.Arg245His, p.Gly264TrpfsX7 or compound heterozygous variants (p.Gly396Asp/Arg245Cys, p.Gly396Asp/Tyr179Cys, p.Gly396Asp/Glu410GlyfsX43, p.Gly264TrpfsX7/Ala385ProfsX23 and p.Gly264TrpfsX7/Glu480del). DNA glycosylase assays of MAP LCL extracts confirmed that all these variants were defective in removing A from an 8-oxoG:A DNA substrate, but retained wild-type OGG1 activity. As a consequence of this defect, MAP LCLs accumulated DNA 8-oxodG in their genome and exhibited a fourfold increase in spontaneous mutagenesis at the PIG-A gene compared with LCLs from healthy donors. They were also hypermutable by KBrO3--a source of DNA 8-oxodG--indicating that the relatively modest spontaneous mutator phenotype associated with MUTYH loss can be significantly enhanced by conditions of oxidative stress. These observations identify accumulation of DNA 8-oxodG and a mutator phenotype as likely contributors to the pathogenesis of MUTYH variants