A new concurrent chemotherapy with vinorelbine and mitomycin C in combination with radiotherapy in patients with locally advanced squamous cell carcinoma of the head and neck

Objective: The purpose of this pilot study was to evaluate the feasibility and toxicity of concurrent chemotherapy with vinorelbine and mitomycin C in combination with accelerated radiotherapy (RT) in patients with locally advanced cancer of the head and neck. Patients and Methods: Between January 2003 and March 2004, 15 patients with T4/N2-3 squamous cell carcinoma (12/15) and with N3 cervical lymph node metastases of carcinoma of unknown primary (3/15) were treated with chemotherapy and simultaneous accelerated RT. Results: 11 patients completed therapy without interruption or dose reduction. Grade 3 - 4 acute mucosal toxicity was observed in 9/15 patients, grade 4 hematologic toxicity in 6/15 patients. At a median follow-up of 7.5 months, 2 patients have died of intercurrent disease, 2 patients have experienced local relapse; 5 patients are alive with no evidence of disease at the primary tumor site. Discussion: The described regimen is highly effective, but led to remarkable side effects

A Mechanistic View of the Role of E3 in Sumoylation

Sumoylation, the covalent attachment of SUMO (Small Ubiquitin-Like Modifier) to proteins, differs from other Ubl (Ubiquitin-like) pathways. In sumoylation, E2 ligase Ubc9 can function without E3 enzymes, albeit with lower reaction efficiency. Here, we study the mechanism through which E3 ligase RanBP2 triggers target recognition and catalysis by E2 Ubc9. Two mechanisms were proposed for sumoylation. While in both the first step involves Ubc9 conjugation to SUMO, the subsequent sequence of events differs: in the first E2-SUMO forms a complex with the target and E3, followed by SUMO transfer to the target. In the second, Ubc9-SUMO binds to the target and facilitates SUMO transfer without E3. Using dynamic correlations obtained from explicit solvent molecular dynamic simulations we illustrate the key roles played by allostery in both mechanisms. Pre-existence of conformational states explains the experimental observations that sumoylation can occur without E3, even though at a reduced rate. Furthermore, we propose a mechanism for enhancement of sumoylation by E3. Analysis of the conformational ensembles of the complex of E2 conjugated to SUMO illustrates that the E2 enzyme is already largely pre-organized for target binding and catalysis; E3 binding shifts the equilibrium and enhances these pre-existing populations. We further observe that E3 binding regulates allosterically the key residues in E2, Ubc9 Asp100/Lys101 E2, for the target recognition

Sequential induction chemotherapy followed by radical chemo-radiation in the treatment of locoregionally advanced head-and-neck cancer

We describe a retrospective series of patients with advanced head-and-neck cancer who were treated with induction chemotherapy followed by radical chemo-radiation. Patients treated with two cycles of induction chemotherapy followed by definitive chemo-radiation for squamous cell carcinoma of the head-and-neck region, from 2001 – 2006 at the Royal Marsden Hospital, formed the basis of this study. Cisplatin (75 mg m−2) on day 1 and 5-FU (1000 mg m−2) day 1 – 4 was the standard regimen used for induction treatment. Cisplatin (100 mg m−2) on day 1 and day 29 was used for concomitant treatment. The radiation was delivered using conformal technique. Tissues containing macroscopic and microscopic disease were treated to doses of 65 Gray (Gy) in 30 fractions and 50 Gy in 25 fractions, respectively. Data on patterns of relapse and acute toxicity (NCICTCv.3.0) were collected. A total of 129 patients were included, median age was 58 (range: 27 – 78). The site of tumour was: oropharynx 70 (54%), larynx 30 (23%), hypopharynx 24 (19%) and other 5 (4%). The median follow-up was 19 months (range: 4 – 58). Local control, disease-specific survival and overall survival at 2 years were 71%, 68% and 63%, respectively. The distant recurrence rate at 2 years was 9%. Ten patients required dose reduction during induction chemotherapy due to toxicity. The dose of 5-FU was reduced in six patients and that of cisplatin in four patients. The incidence of grade 3/4 toxicity was: neutropenia 5%, thrombocytopenia 1%, nausea and vomiting 3%. One cycle of concurrent cisplatin was omitted in 23 patients due to toxicity. Full-dose radiotherapy was administered to 98% of patients. The incidence of grade 3/4 toxicity was: skin 20%, dysphagia 65%, mucositis 60%, neutropenia 3%, anaemia 1%, nausea and vomiting 4%, nephrotoxicity 1%. Induction chemotherapy followed by radical chemo-radiation is a safe and tolerable regimen in the treatment of advanced head-and-neck cancer. Distant recurrence rates are lower with equivalent local control and survival compared to chemo-radiation alone (historical controls)

PDMS microfluidics developed for polymer based photonic biosensors

In this work, advances in the fabrication technology and functional analysis of a polymer microfluidic system-as a significant part of a developed polymer photonic biosensor-are reported. Robust and cost-effective microfluidics in PDMS including sample preparation functions is designed and realized by using SU-8 moulding replica. Surface modification strategies using Triton X-100 and PDMS-PEO and their effect on device sealing and non-specific protein adsorption are investigated by contact angle measurement and in situ fluorescence microscopy. © 2014 Springer-Verlag Berlin Heidelberg

Decay spectroscopy of Cd-129

Excited states of $^{129}$In populated following the $\beta$-decay of $^{129}$Cd were experimentally studied with the GRIFFIN spectrometer at the ISAC facility of TRIUMF, Canada. A 480-MeV proton beam was impinged on a uranium carbide target and $^{129}$Cd was extracted using the Ion Guide Laser Ion Source (IG-LIS). $\beta$- and $\gamma$-rays following the decay of $^{129}$Cd were detected with the GRIFFIN spectrometer comprising the plastic scintillator SCEPTAR and 16 high-purity germanium (HPGe) clover-type detectors. %, along with the $\beta$-particles were detected with SCEPTAR. From the $\beta$-$\gamma$-$\gamma$ coincidence analysis, 32 new transitions and 7 new excited states were established, expanding the previously known level scheme of $^{129}$In. The $\log ft$ values deduced from the $\beta$-feeding intensities suggest that some of the high-lying states were populated by the $\nu 0 g_{7/2} \rightarrow \pi 0 g_{9/2}$ allowed Gamow-Teller (GT) transition, which indicates that the allowed GT transition is more dominant in the $^{129}$Cd decay than previously reported. Observation of fragmented Gamow-Teller strengths is consistent with theoretical calculations.Comment: 13 pages, 9 figures, to be published in Physical Review

Disease control and functional outcome in three modern combined organ preserving regimens for locally advanced squamous cell carcinoma of the head and neck (SCCHN)

<p>Abstract</p> <p>Purpose</p> <p>To report our experience on disease control and functional outcome using three modern combined-modality approaches for definitive radiochemotherapy of locally advanced SCCHN with modern radiotherapy techniques: radiochemotherapy (RChT), radioimmunotherapy (RIT) with cetuximab, or induction chemotherapy with docetaxel, cisplatin, and 5-FU (TPF) combined with either RChT or RIT.</p> <p>Methods</p> <p>Toxicity and outcome was retrospectively analysed in patients receiving definitive RChT, RIT, or induction chemotherapy followed by RChT or RIT between 2006 and 2009. Outcome was estimated using Kaplan-Meier analyses, toxicity was analysed according to CTCAE v 3.0.</p> <p>Results</p> <p>Thirty-eight patients were treated with RChT, 38 patients with RIT, 16 patients received TPF followed by either RChT or RIT. Radiotherapy was mostly applied as IMRT (68%). Long-term toxicity was low, only one case of grad III dysphagia requiring oesophageal dilatation, no case of either xerostomia ≥ grade II or cervical plexopathy were observed. Median overall survival (OS) was 25.7 months (RChT) and 27.7 months (RIT), median locoregional progression-free survival (PFS) was not reached yet. Subgroup analysis showed no significant differences between TPF, RChT, and RIT despite higher age and co-morbidities in the RIT group. Results suggested improved OS, distant and overall PFS for the TPF regimen.</p> <p>Conclusion</p> <p>Late radiation effects in our cohort are rare. No significant differences in outcome between RChT and RIT were observed. Adding TPF suggests improved progression-free and overall survival, impact of TPF on locoregional PFS was marginal, therefore radiotherapeutic options for intensification of local treatment should be explored.</p

Cost-Effectiveness of Adding Cetuximab to Platinum-Based Chemotherapy for First-Line Treatment of Recurrent or Metastatic Head and Neck Cancer

To assess the cost effectiveness of adding cetuximab to platinum-based chemotherapy in first-line treatment of patients with recurrent or metastatic head and neck squamous cell carcinoma (HNSCC) from the perspective of the Canadian public healthcare system.We developed a Markov state transition model to project the lifetime clinical and economic consequences of recurrent or metastatic HNSCC. Transition probabilities were derived from a phase III trial of cetuximab in patients with recurrent or metastatic HNSCC. Cost estimates were obtained from London Health Sciences Centre and the Ontario Case Costing Initiative, and expressed in 2011 CAD. A three year time horizon was used. Future costs and health benefits were discounted at 5%.In the base case, cetuximab plus platinum-based chemotherapy compared to platinum-based chemotherapy alone led to an increase of 0.093 QALY and an increase in cost of $36,000 per person, resulting in an incremental cost effectiveness ratio (ICER) of$386,000 per QALY gained. The cost effectiveness ratio was most sensitive to the cost per mg of cetuximab and the absolute risk of progression among patients receiving cetuximab.The addition of cetuximab to standard platinum-based chemotherapy in first-line treatment of patients with recurrent or metastatic HNSCC has an ICER that exceeds $100,000 per QALY gained. Cetuximab can only be economically attractive in this patient population if the cost of cetuximab is substantially reduced or if future research can identify predictive markers to select patients most likely to benefit from the addition of cetuximab to chemotherapy

Use of cancer-specific yeast-secreted in vivo biotinylated recombinant antibodies for serum biomarker discovery

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Crystal Structure of UBA2ufd-Ubc9: Insights into E1-E2 Interactions in Sumo Pathways

Canonical ubiquitin-like proteins (UBLs) such as ubiquitin, Sumo, NEDD8, and ISG15 are ligated to targets by E1-E2-E3 multienzyme cascades. The Sumo cascade, conserved among all eukaryotes, regulates numerous biological processes including protein localization, transcription, DNA replication, and mitosis. Sumo conjugation is initiated by the heterodimeric Aos1-Uba2 E1 enzyme (in humans called Sae1-Uba2), which activates Sumo's C-terminus, binds the dedicated E2 enzyme Ubc9, and promotes Sumo C-terminal transfer between the Uba2 and Ubc9 catalytic cysteines. To gain insights into details of E1-E2 interactions in the Sumo pathway, we determined crystal structures of the C-terminal ubiquitin fold domain (ufd) from yeast Uba2 (Uba2ufd), alone and in complex with Ubc9. The overall structures of both yeast Uba2ufd and Ubc9 superimpose well on their individual human counterparts, suggesting conservation of fundamental features of Sumo conjugation. Docking the Uba2ufd-Ubc9 and prior full-length human Uba2 structures allows generation of models for steps in Sumo transfer from Uba2 to Ubc9, and supports the notion that Uba2 undergoes remarkable conformational changes during the reaction. Comparisons to previous structures from the NEDD8 cascade demonstrate that UBL cascades generally utilize some parallel E1-E2 interaction surfaces. In addition, the structure of the Uba2ufd-Ubc9 complex reveals interactions unique to Sumo E1 and E2. Comparison with a previous Ubc9-E3 complex structure demonstrates overlap between Uba2 and E3 binding sites on Ubc9, indicating that loading with Sumo and E3-catalyzed transfer to substrates are strictly separate steps. The results suggest mechanisms establishing specificity and order in Sumo conjugation cascades