Citations

Purpose Primary CNS lymphoma (PCNSL) is an aggressive lymphoma but clinically validated biologic markers that can predict natural history to tailor treatment according to risk are lacking. Several genetic changes including BCL6 rearrangements and deletion of 6q22, containing the putative tumor suppressor gene PTPRK, are potential risk predictors. Herein we determined the prevalence and survival impact of del(6)(q22) and BCL6, immunoglobulin heavy chain (IGH), and MYC gene rearrangements in a large PCNSL cohort treated in a single center. Patients and Methods Interphase fluorescence in situ hybridization was performed using two-color probes for BCL6, MYC, IGH-BCL6, and del(6)(q22) on thin sections of 75 paraffin-embedded samples from 75 HIV-negative, immunocompetent patients newly diagnosed with PCNSL. Survival data were analyzed using Kaplan-Meier survival curves, log-rank tests, and proportional hazards regression adjusting for age, deep structure involvement, and high-dose methotrexate (HDMTX) treatment. Results The prevalence of del(6)(q22) and BCL6, IGH, and MYC translocations was 45%,17%, 13%, and 3%, respectively. The presence of del(6)(q22) and/or a BCL6 translocation was associated with inferior overall survival (OS; P = .0097). The presence of either del(6)(q22) alone or a BCL6 translocation alone was also associated with inferior OS (P = .0087). Univariable results held after adjusting for age, deep structure involvement, and HDMTX. Conclusion Del (6)(q22) and BCL6 rearrangements are common in PCNSL and predict for decreased OS independent of deep structure involvement and HDMTX. Unlike systemic diffuse large B-cell lymphoma, del(6)(q22) is common and IGH translocations are infrequent and usually involve BCL6 rather than BCL2, suggesting a distinct pathogenesis.

Purpose To determine prognostic factors and impact of adjuvant chemotherapy (CT) and radiotherapy (RT) on overall survival (OS) after resection of pancreatic adenocarcinoma. Patients and Methods We performed a retrospective review 472 consecutive patients who underwent complete resection with negative margins (R0) for invasive carcinoma (T1-3N0-1M0) of the pancreas between 1975 and 2005 at the Mayo Clinic in Rochester, MN. Exclusion criteria included metastatic or unresectable disease at surgery, positive surgical margins, and indolent tumor types (islet cell tumors and mucinous cystadenocarcinoma). Median RT dose was 50.4 Gy in 28 fractions; 98% of RT patients also received concurrent fluorouracil-based CT. Results Six patients died within 30 days of surgery. For the 466 surviving patients, median follow-up was 32.4 months; median OS was 21.6 months. Median OS after adjuvant CT-RT was 25.2 versus 19.2 months after no adjuvant therapy (P = .001). Two-year OS was 50% versus 39%, and 5-year OS was 28% versus 17%. Adverse prognostic factors identified by univariate and multivariate analysis included positive lymph nodes (risk ratio [RR] = 1.3; P < .001), high histologic grade (RR = 1.2; P < .001), and no adjuvant therapy (RR = 1.3; P < .001). Tumor extension beyond the pancreas was an adverse prognostic factor by univariate analysis alone (P = .03). Patients receiving adjuvant therapy had more adverse prognostic factors than those not receiving adjuvant therapy (P = .001). Conclusion This study represents one of the largest, single-institution, retrospective reviews of adjuvant therapy in patients after R0 resection of carcinoma of the pancreas. Overall survival was better in patients who received adjuvant CT-RT.

Haemopoiesis is a fundamental physiologic process found in many animals. Among mammals, the diversity in size and function required suitable adaptations of this process. In this work, we use allometric principles to determine whether this required a change in the basic architecture of haemopoiesis. We show that it is possible to express both the number and rate with which haemopoietic stem cells replicate as well as total marrow output across all mammals as a function of adult mass. This unified view, which is compatible with the existing data, suggests that there was no need for major adaptations in the architecture of haemopoiesis across mammals.

Background— The clinical efficacy of alcohol septal ablation for drug-refractory hypertrophic cardiomyopathy remains unclear. This study examines the outcome of alcohol septal ablation performed at a tertiary hypertrophic cardiomyopathy referral center. Methods and Results— Among 601 patients with severely symptomatic obstructive hypertrophic cardiomyopathy referred for alcohol septal ablation or myectomy from 1998 to 2006, 138 patients (median age, 64 years; 39% men) chose to undergo ablation. Procedural complications included death in 1.4%, sustained ventricular arrhythmias in 3%, tamponade in 3%, and pacemaker implantation in 20%. This rate was higher than a combined complication rate of 5% in age- and gender-matched patients who had undergone septal myectomy at Mayo Clinic ( P <0.0001). Four-year survival free of all mortality was 88.0% (95% confidence interval, 79.4 to 97.5%), which was similar to that of the age- and gender-matched patients who had undergone myectomy ( P =0.18). Six patients had documented ventricular arrhythmias after ablation, 4 of whom had successful intervention. Four-year survival free of death and severe New York Heart Association class III/IV symptoms after septal ablation was 76.4%, and 71 patients (51%) became asymptomatic. Myectomy patients ≤65 years of age had significantly better survival free of death and severe symptoms ( P =0.01). Conclusions— Alcohol septal ablation is an efficacious procedure if performed in an experienced institution and may resolve symptoms in a subset of patients with obstructive hypertrophic cardiomyopathy. However, the procedural complication rate exceeds that of myectomy. Patients ≤65 years of age have better symptom resolution with myectomy. No impairment in short-term survival was noted in this nonrandomized study, but the long-term outcome remains unknown.

Mutations in 11 genes that encode ion channels or their associated proteins cause inherited long QT syndrome (LQTS) and account for ≈75–80% of cases (LQT1–11). Direct sequencing of SNTA1 , the gene encoding α1-syntrophin, was performed in a cohort of LQTS patients that were negative for mutations in the 11 known LQTS-susceptibility genes. A missense mutation (A390V-SNTA1) was found in a patient with recurrent syncope and markedly prolonged QT interval (QTc, 530 ms). SNTA1 links neuronal nitric oxide synthase (nNOS) to the nNOS inhibitor plasma membrane Ca-ATPase subtype 4b (PMCA4b); SNTA1 also is known to associate with the cardiac sodium channel SCN5A. By using a GST-fusion protein of the C terminus of SCN5A, we showed that WT-SNTA1 interacted with SCN5A, nNOS, and PMCA4b. In contrast, A390V-SNTA1 selectively disrupted association of PMCA4b with this complex and increased direct nitrosylation of SCN5A. A390V-SNTA1 expressed with SCN5A, nNOS, and PMCA4b in heterologous cells increased peak and late sodium current compared with WT-SNTA1, and the increase was partially inhibited by NOS blockers. Expression of A390V-SNTA1 in cardiac myocytes also increased late sodium current. We conclude that the A390V mutation disrupted binding with PMCA4b, released inhibition of nNOS, caused S -nitrosylation of SCN5A, and was associated with increased late sodium current, which is the characteristic biophysical dysfunction for sodium-channel-mediated LQTS (LQT3). These results establish an SNTA1-based nNOS complex attached to SCN5A as a key regulator of sodium current and suggest that SNTA1 be considered a rare LQTS-susceptibility gene.

The SCFFBW7 ubiquitin ligase degrades proteins involved in cell division, growth, and differentiation and is commonly mutated in cancers. The Fbw7 locus encodes three protein isoforms that occupy distinct subcellular localizations, suggesting that each has unique functions. We used gene targeting to create isoform-specific Fbw7-null mutations in human cells and found that the nucleoplasmic Fbw7α isoform accounts for almost all Fbw7 activity toward cyclin E, c-Myc, and sterol regulatory element binding protein 1. Cyclin E sensitivity to Fbw7 varies during the cell cycle, and this correlates with changes in cyclin E–cyclin-dependent kinase 2 (CDK2)–specific activity, cyclin E autophosphorylation, and CDK2 inhibitory phosphorylation. These data suggest that oscillations in cyclin E–CDK2-specific activity during the cell cycle regulate the timing of cyclin E degradation. Moreover, they highlight the utility of adeno-associated virus–mediated gene targeting in functional analyses of complex loci.