Members of a mammalian SNARE complex interact in the endoplasmic reticulum in vivo and are found in COPI vesicles

Verrier SE, Willmann M, Wenzel D, Winter U, Fischer von Mollard G, Soeling H-D. Members of a mammalian SNARE complex interact in the endoplasmic reticulum in vivo and are found in COPI vesicles. EUROPEAN JOURNAL OF CELL BIOLOGY. 2008;87(11):863-878.Retrograde traffic between the Golgi apparatus and the endoplasmic reticulum (ER) is largely mediated by COPI-coated transport vesicles. In mammalian cells, retrograde traffic can pass through an intermediate compartment. Here, we report that the mammalian soluble N-ethylmaleimide-sensitive factor (NSF) attachment receptor (SNARE) proteins mSec22b, mUse1/D12, mSec20/BNIP1, and syntaxin 18 form a quaternary SNARE complex. Fluorescence resonance energy transfer (FRET) experiments prove that these interactions occur in the ER of living cells. In addition, mUse1/D12 and mSec20/BNIP1 form homo-oligomers in vivo. Furthermore, we show that rnSec22b, mUse1/D12, mSec20/BNIP1, and syntaxin 18 are recruited into COPI-coated vesicles formed in vitro. Immunogold electron microscopy confirmed that these SNARE proteins colocalize with the KDEL receptor ERD2 in COPI-coated vesicles. Moreover, both FRET and immunoprecipitation experiments reveal interactions of these SNAREs with both ERD2 and COPI subunits. We conclude that the SNAREs described here are sorted via interaction with components of the COPI-dependent budding complex into Golgi-to-ER retrograde COPI vesicles and function in retrograde transport from the Golgi to the ER Golgi intermediate compartment (ERGIC) or the ER. (C) 2008 Elsevier GmbH. All rights reserved

Efficacy and Safety of Irinotecan-Based Chemotherapy for Advanced Colorectal Cancer outside Clinical Trials: An Observational Study

Background: This prospective observational study in typical community-based outpatient clinics evaluated the efficacy and toxicity of weekly and biweekly irinotecan-based chemotherapies and their compatibility depending on age. Methods: 601 patients with advanced or metastatic colorectal cancer receiving first-, second-, or third-line irinotecanbased therapy were regularly analyzed for response and toxicity until the end of therapy. Results: The median age was 65 (28–87) years, approximately one-third of the patients were ≥70 years old. Of all patients, 405 were treated weekly and 68 biweekly. Median overall survival (OS) for first-line therapy was 26.5 months for the <70-year-old patients and 19.4 months for the ≥70-year-old patients. Toxicities were moderate in all groups. Tumor growth control rates (TCR) and median time to progression (TTP) were marginally better for patients <70 years old. Median TTP was 9.9 months in first-line therapy, 9.8 months after adjuvant therapy, 7.7 months in second-line, and 6.4 months in third-line therapy. Conclusions: Toxicity and response data from this observational study clearly confirm the positive results from previous clinical studies and show a slight advantage in efficacy for the <70-year-old patients.Hintergrund: Diese Phase-IV-Studie wurde durchgeführt, um die Effizienz und Sicherheit Irinotecan-haltiger Regime außerhalb klinischer Studien und großer Studienzentren zu untersuchen. Der Schwerpunkt lag auf dem Vergleich wöchentlicher und zweiwöchentlicher Schemata sowie auf der Analyse von Wirksamkeit und Verträglichkeit in Abhängigkeit vom Alter. Methoden: Daten von 601 Patienten mit fortgeschrittenem bzw. metastasiertem kolorektalen Karzinom, die Irinotecan-haltige Erst-, Zweit- oder Drittlinientherapie erhielten, wurden analysiert. Ansprechen und Toxizität wurden in regelmäßigen Abständen bis zur Beendigung der Therapie dokumentiert. Ergebnisse: Das mediane Alter betrug 65 (28–87) Jahre, ein Drittel der Patienten waren 70 Jahre oder älter. 405 Patienten erhielten die Chemotherapie wöchentlich, 68 zweiwöchentlich. Das mediane Gesamtüberleben betrug 26,5 Monate für die <70-jährigen und 19,4 Monate für die ≥70-jährigen Patienten. Die Toxizitäten waren bei allen Gruppen moderat ausgeprägt. Sowohl die Ansprechrate als auch die mediane Zeit bis zur Progression (TTP) waren für Patienten unter 70 Jahren geringfügig besser. Die mediane TTP lag in der Ersttherapie bei 9,9 bzw. 9,8 Monaten ohne bzw. mit adjuvanter Therapie, in der Zweitlinientherapie bei 7,7 und in der Drittlinientherapie bei 6,4 Monaten. Schlussfolgerungen: Die Daten dieser Phase- IV-Studie bestätigen die Ergebnisse früherer klinischer Studien und zeigen leichte Vorteile bei der Wirksamkeit für <70-jährige Patienten

Comprehensive analysis of isolated der(1;7)(q10;p10) in a large international homogenous cohort of patients with myelodysplastic syndromes

The karyotype is a strong independent prognostic factor in myelodysplastic syndromes (MDS). Since the implementation of the new comprehensive cytogenetic scoring system for MDS, chromosome 7 anomalies are no longer generally assigned to poor risk features but are thoroughly separated. However, der(1;7)(q10;p10), hereinafter der(1;7), is merged into the group labeled "any other single" and belongs to the intermediate risk group, just by definition due to lack of adequate clinical data. The aim of our international collaborative was to clarify the "real" prognostic impact of der(1;7) on a homogenous and well-documented data base. We performed detailed analysis of 63 MDS patients with isolated der(1;7) constituting the largest cohort hitherto reported. Furthermore, clinical data are compared with those of patients with isolated del(7q) and isolated monosomy 7. Median overall survival (OS) of patients with der(1;7) is 26 months (hazard ratio (HR) 0.91 for del(7q) vs der(1;7) and 2.53 for monosomy 7 vs der(1;7)). The der(1;7) is associated with profound thrombocytopenia most probably causing the reduced OS which is in striking contrast to the low risk for AML transformation (HR 3.89 for del(7q) vs der(1;7) and 5.88 for monosomy 7 vs der(1;7)). Molecular karyotyping indicates that der(1;7) is generated in a single step during mitosis and that a chromosomal imbalance rather than a single disrupted gene accounts for malignancy. Thus, the current cytogenetic scoring system assigning isolated der(1;7) to the intermediate risk group is now confirmed by a sufficient data set.status: publishe