9 research outputs found
Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study
Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation
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Response to neoadjuvant radiation therapy for rectal cancer improves survival
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Improvement of survival with response to neoadjuvant radiation therapy for rectal cancer
To determine whether patients with a complete or near-complete response to neoadjuvant radiation therapy (XRT) have improved survival compared with those with less of a response and to compare survival between patients with disease downstaged after neoadjuvant XRT and patients with stage I disease undergoing resection alone.
Retrospective cohort of 10,971 patients (3760 patients with neoadjuvant XRT; 7211 with stage I disease with resection alone) from the Surveillance, Epidemiology, and End Results registry using data from January 1, 1994, through December 31, 2003.
Overall survival and disease-specific survival (DSS) of patients undergoing resection for nonmetastatic rectal adenocarcinoma receiving neoadjuvant XRT and patients with stage I disease undergoing surgical resection alone.
The 5-year DSS and overall survival were 94% and 82%, respectively, for responders to neoadjuvant XRT, 78% and 60%, respectively, for nonresponders, and 97% and 79%, respectively, for patients with stage I disease undergoing resection alone. Responders had improved DSS (P < .001) and overall survival (P < .001) compared with nonresponders by Cox regression. Patients with stage I disease undergoing resection alone had improved DSS (P = .01) but not overall survival (P = .89) compared with XRT responders.
Patients with rectal adenocarcinoma downstaged after neoadjuvant XRT have improved survival compared with nonresponders. While DSS is excellent for responders to neoadjuvant XRT, it did not equal the DSS of patients with stage I disease undergoing resection alone
A clinical comparative analysis of crush/clamp, stapler, and dissecting sealer hepatic transection methods
Several methods for hepatic parenchymal division exist. The primary aim was to assess differences in postoperative bile leaks, operative blood loss, and margin status between three transection methods: crush/clamp (CC), stapler (SP), or dissecting sealer (DS).
A single institution, retrospective cohort study was performed on data collected over a three-year period in patients undergoing elective liver resection using the CC, SP, or DS. Patients were excluded if multiple methods of transection were used or for intraoperative death. The association of bile leak with transection type was assessed. A logistic regression model was tested to assess if blood loss was associated with the covariates of transection method, use of portal inflow occlusion, extent of liver resection, and other concurrent major operations.
Analyses included 141 patients. The stapler method was quicker than the other methods (p=0.01). The risk of postoperative bile leak was no different between CC, SP, and DS transection methods (p=0.23). There was no difference in mean blood loss or transfusions; however, hepatectomies performed with DS were associated with an increased risk of blood loss > or = 1000 mL compared to CC (p=0.04). There were no differences in mean surgical margin between the three methods.
The risk of bile leaks was not different between the three methods. While mean blood loss was similar, hepatectomy performed with the DS was associated with an increased risk of having operative blood loss > or = 1000 mL compared to CC. Margins were equal by all methods. The stapler method was quicker
Liver transplantation for non-hepatocellular carcinoma malignancy1
Liver transplantation (LT) for hepatocellular carcinoma is effective for selected patients. LT for other malignancies like cholangiocarcinoma (CCA), hepatoblastoma (HB), hepatic epithelioid hemangioepithelioma (HEHE), angiosarcoma (AS), and neuroendocrine tumors (NET) is being defined. For CCA, series that did not emphasize highly selected early stage disease and neoadjuvant or adjuvant chemoradiation had an average 5-year survival of 10%. However, emphasizing neoadjuvant radiation and chemosensitization in operatively confirmed stage I or II hilar CCA has led to improved 5-year survival, up to 82%. LT is indicated under strict research protocols at selected centers, for patients with early stage CCA and anatomically unresectable (Bismuth type IV) lesions. HB is typically sensitive to cisplatin-based chemotherapy. LT plays a role as primary surgical therapy for those individuals in whom tumors remain unresectable after chemotherapy or as rescue therapy for those who are incompletely resected, recur after resection, or develop hepatic insufficiency after chemotherapy and/or resection. Long-term survival is reported at 58–88%. HEHE is a multifocal tumor that lies somewhere between benign hemangiomas and malignant AS. The extensive multifocal nature makes resection difficult and LT an attractive option. Series on LT for HEHE report overall survival of 71–78% at 5 years. However, AS is an aggressive tumor and LT is contraindicated. For NET, resection of the primary tumor and all gross metastatic disease is reported to provide 5-year survival of 70–85%. LT has been employed for some patients for unresectable tumors or for palliation of medically uncontrollable symptoms with 5-year survival reported between 36% and 80%
Liver transplantation for acute hepatic failure
There are numerous causes of acute hepatic failure (AHF). Cerebral edema, coagulopathy, renal failure, metabolic disturbances and infection are the main clinical sequelae. Patients with AHF should be stabilized when first encountered and transferred to the nearest liver transplant center, as AHF progresses quickly and is often fatal. There are few adequate medical interventions and care of patients with AHF is supportive until spontaneous recovery ensues. If recovery does not appear to occur, most causes of AHF are well accepted indications for liver transplantation
Clinical and genetic characteristics of late-onset Huntington's disease
Background: The frequency of late-onset Huntington's disease (>59 years) is assumed to be low and the clinical course milder. However, previous literature on late-onset disease is scarce and inconclusive. Objective: Our aim is to study clinical characteristics of late-onset compared to common-onset HD patients in a large cohort of HD patients from the Registry database. Methods: Participants with late- and common-onset (30–50 years)were compared for first clinical symptoms, disease progression, CAG repeat size and family history. Participants with a missing CAG repeat size, a repeat size of ≤35 or a UHDRS motor score of ≤5 were excluded. Results: Of 6007 eligible participants, 687 had late-onset (11.4%) and 3216 (53.5%) common-onset HD. Late-onset (n = 577) had significantly more gait and balance problems as first symptom compared to common-onset (n = 2408) (P <.001). Overall motor and cognitive performance (P <.001) were worse, however only disease motor progression was slower (coefficient, −0.58; SE 0.16; P <.001) compared to the common-onset group. Repeat size was significantly lower in the late-onset (n = 40.8; SD 1.6) compared to common-onset (n = 44.4; SD 2.8) (P <.001). Fewer late-onset patients (n = 451) had a positive family history compared to common-onset (n = 2940) (P <.001). Conclusions: Late-onset patients present more frequently with gait and balance problems as first symptom, and disease progression is not milder compared to common-onset HD patients apart from motor progression. The family history is likely to be negative, which might make diagnosing HD more difficult in this population. However, the balance and gait problems might be helpful in diagnosing HD in elderly patients