111 research outputs found

    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

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    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 non-randomised, single-centre comparison of induction chemotherapy followed by radiochemotherapy versus concomitant chemotherapy with hyperfractionated radiotherapy in inoperable head and neck carcinomas

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    BACKGROUND: The application of induction chemotherapy failed to provide a consistent benefit for local control in primary treatment of advanced head and neck (H&N) cancers. The aim of this study was to compare the results of concomitant application of radiochemotherapy for treating locally advanced head-and-neck carcinoma in comparison with the former standard of sequential radiochemotherapy. METHODS: Between 1987 and 1995 we treated 122 patients with unresectable (stage IV head and neck) cancer by two different protocols. The sequential protocol (SEQ; 1987–1992) started with two courses of neoadjuvant chemotherapy (cisplatin [CDDP] + 120-h continuous infusions (c.i.) of folinic acid [FA] and 5-fluorouracil [5-FU]), followed by a course of radiochemotherapy using conventional fractionation up to 70 Gy. The concomitant protocol (CON; since 1993) combined two courses of FA/5-FU c.i. plus mitomycin (MMC) concomitantly with a course of radiotherapy up to 30 Gy in conventional fractionation, followed by a hyperfractionated course up to 72 Gy. Results from the two groups were compared. RESULTS: Patient and tumor characteristics were balanced (SEQ = 70, CON = 52 pts.). Mean radiation dose achieved (65.3 Gy vs. 71.6 Gy, p = 0.00), response rates (67 vs. 90 % for primary, p = 0.02), and local control (LC; 17.6% vs. 41%, p = 0.03), were significantly lower in the SEQ group, revealing a trend towards lower disease-specific (DSS; 19.8% vs. 31.4%, p = 0.08) and overall (14.7% vs. 23.7%, p = 0.11) survival rates after 5 years. Mucositis grades III and IV prevailed in the CON group (54% versus 44%). Late toxicity was similar in both groups. CONCLUSION: Concurrent chemotherapy seemed more effective in treating head and neck tumors than induction chemotherapy followed by chemoradiation, resulting in better local control and a trend towards improved survival

    Anaplastic thyroid carcinoma: three protocols combining doxorubicin, hyperfractionated radiotherapy and surgery

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    Patients with anaplastic thyroid carcinoma can rarely be cured, but every effort should be made to prevent death due to suffocation. Between 1984 and 1999, 55 consecutive patients with anaplastic thyroid carcinoma were prospectively treated according to a combined regimen consisting of hyperfractionated radiotherapy, doxorubicin, and when feasible surgery. Radiotherapy was carried out for 5 days a week. The daily fraction until 1988 was 1.0 GyΓ—2 (A) and 1989–92 1.3 GyΓ—2 (B) . Thereafter 1.6 GyΓ—2 (C) was administered. Radiotherapy was administered to a total target dose of 46 Gy; of which 30 Gy was administered preoperatively in the first two protocols (A and B), while the whole dose was given preoperatively in the third protocol (C). The therapy was otherwise identical. Twenty mg doxorubicin was administered intravenously weekly. Surgery was possible in 40 patients. No patient failed to complete the protocol due to toxicity. In only 13 cases (24%) was death attributed to local failure. Five patients (9%) β€˜had a survival’ exceeding 2 years. No signs of local recurrence were seen in 33 patients (60%); 5 out of 16 patients in Protocol A, 11 out of 17 patients in Protocol B, 17 out of 22 patients in Protocol C (P=0.017). In the 40 patients undergoing additional surgery, no signs of local recurrence were seen in 5 out of 9 patients, 11 out of 14 patients and 17 out of 17 patients, respectively (P=0.005)

    Neck-motor interactions trigger rotation of the kinesin stalk

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    Rotation of the coiled-coil stalk of the kinesin-14 motors is thought to drive displacements or steps by the motor along microtubules, but the structural changes that trigger stalk rotation and the nucleotide state in which it occurs are not certain. Here we report a kinesin-14 neck mutant that releases ADP more slowly than wild type and shows weaker microtubule affinity, consistent with defective stalk rotation. Unexpectedly, crystal structures show the stalk fully rotated – neck-motor interactions destabilize the stalk, causing it to rotate and ADP to be released, and alter motor affinity for microtubules. A new structural pathway accounts for the coupling of stalk rotation – the force-producing stroke – to changes in motor affinity for nucleotide and microtubules. Sequential disruption of salt bridges that stabilize the unrotated stalk could cause the stalk to initiate and complete rotation in different nucleotide states

    LIM and SH3 Protein -1 Modulates CXCR2-Mediated Cell Migration

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    BACKGROUND: The chemokine receptor CXCR2 plays a pivotal role in migration of neutrophils, macrophages and endothelial cells, modulating several biological responses such as angiogenesis, wound healing and acute inflammation. CXCR2 is also involved in pathogenesis of chronic inflammation, sepsis and atherosclerosis. The ability of CXCR2 to associate with a variety of proteins dynamically is responsible for its effects on directed cell migration or chemotaxis. The dynamic network of such CXCR2 binding proteins is termed as "CXCR2 chemosynapse". Proteomic analysis of proteins that co-immunoprecipitated with CXCR2 in neutrophil-like dHL-60 cells revealed a novel protein, LIM and SH3 protein 1 (LASP-1), binds CXCR2 under both basal and ligand activated conditions. LASP-1 is an actin binding cytoskeletal protein, involved in the cell migration. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate that CXCR2 and LASP-1 co-immunoprecipitate and co-localize at the leading edge of migrating cells. The LIM domain of LASP-1 directly binds to the carboxy-terminal domain (CTD) of CXCR2. Moreover, LASP-1 also directly binds the CTD of CXCR1, CXCR3 and CXCR4. Using a site-directed and deletion mutagenesis approach, Iso323-Leu324 of the conserved LKIL motif on CXCR2-CTD was identified as the binding site for LASP-1. Interruption of the interaction between CXCR2-CTD and LIM domain of LASP-1 by dominant negative and knock down approaches inhibited CXCR2-mediated chemotaxis. Analysis for the mechanism for inhibition of CXCR2-mediated chemotaxis indicated that LASP-1/CXCR2 interaction is essential for cell motility and focal adhesion turnover involving activation of Src, paxillin, PAK1, p130CAS and ERK1/2. CONCLUSIONS/SIGNIFICANCE: We demonstrate here for the first time that LASP-1 is a key component of the "CXCR2 chemosynapse" and LASP-1 interaction with CXCR2 is critical for CXCR2-mediated chemotaxis. Furthermore, LASP-1 also directly binds the CTD of CXCR1, CXCR3 and CXCR4, suggesting that LASP-1 is a general mediator of CXC chemokine mediated chemotaxis. Thus, LASP-1 may serve as a new link coordinating the flow of information between chemokine receptors and nascent focal adhesions, especially at the leading edge. Thus the association between the chemokine receptors and LASP-1 suggests to the presence of a CXC chemokine receptor-LASP-1 pro-migratory module in cells governing the cell migration

    Feasibility and Effectiveness of Basic Lymphedema Management in Leogane, Haiti, an Area Endemic for Bancroftian Filariasis

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    Lymphatic filariasis is a parasitic disease that is spread by mosquitoes. In tropical countries where lymphatic filariasis occurs, approximately 14 million people suffer from chronic swelling of the leg, known as lymphedema. Repeated episodes of bacterial skin infection (acute attacks) cause lymphedema to progress to its disfiguring form, elephantiasis. To help achieve the goal of eliminating lymphatic filariasis globally, the World Health Organization recommends basic lymphedema management, which emphasizes hygiene, skin care, exercise, and leg elevation. Its effectiveness in reducing acute attack frequency, as well as the role of compressive bandaging, have not been adequately evaluated in filariasis-endemic areas. Between 1995 and 1998, we studied 175 people with lymphedema of the leg in Leogane, Haiti. During Phase I of the study, when compression bandaging was used to reduce leg volume, the average acute attack rate was 1.56 episodes per year; it was greater in people who were illiterate and those who used compression bandages. After March 1997, when hygiene and skin care were emphasized and bandaging discouraged, acute attack frequency significantly decreased to 0.48 episodes per year. This study highlights the effectiveness of hygiene and skin care, as well as limitations of compressive bandaging, in managing lymphedema in filariasis-endemic areas

    A meta-analysis of hyperfractionated and accelerated radiotherapy and combined chemotherapy and radiotherapy regimens in unresected locally advanced squamous cell carcinoma of the head and neck

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    BACKGROUND: Former meta-analyses have shown a survival benefit for the addition of chemotherapy (CHX) to radiotherapy (RT) and to some extent also for the use of hyperfractionated radiation therapy (HFRT) and accelerated radiation therapy (AFRT) in locally advanced squamous cell carcinoma (SCC) of the head and neck. However, the publication of new studies and the fact that many older studies that were included in these former meta-analyses used obsolete radiation doses, CHX schedules or study designs prompted us to carry out a new analysis using strict inclusion criteria. METHODS: Randomised trials testing curatively intended RT (β‰₯60 Gy in >4 weeks/>50 Gy in <4 weeks) on SCC of the oral cavity, oropharynx, hypopharynx, and larynx published as full paper or in abstract form between 1975 and 2003 were eligible. Trials comparing RT alone with concurrent or alternating chemoradiation (5-fluorouracil (5-FU), cisplatin, carboplatin, mitomycin C) were analyzed according to the employed radiation schedule and the used CHX regimen. Studies comparing conventionally fractionated radiotherapy (CFRT) with either HFRT or AFRT without CHX were separately examined. End point of the meta-analysis was overall survival. RESULTS: Thirty-two trials with a total of 10 225 patients were included into the meta-analysis. An overall survival benefit of 12.0 months was observed for the addition of simultaneous CHX to either CFRT or HFRT/AFRT (p < 0.001). Separate analyses by cytostatic drug indicate a prolongation of survival of 24.0 months, 16.8 months, 6.7 months, and 4.0 months, respectively, for the simultaneous administration of 5-FU, cisplatin-based, carboplatin-based, and mitomycin C-based CHX to RT (each p < 0.01). Whereas no significant gain in overall survival was observed for AFRT in comparison to CFRT, a substantial prolongation of median survival (14.2 months, p < 0.001) was seen for HFRT compared to CFRT (both without CHX). CONCLUSION: RT combined with simultaneous 5-FU, cisplatin, carboplatin, and mitomycin C as single drug or combinations of 5-FU with one of the other drugs results in a large survival advantage irrespective the employed radiation schedule. If radiation therapy is used as single modality, hyperfractionation leads to a significant improvement of overall survival. Accelerated radiation therapy alone, especially when given as split course radiation schedule or extremely accelerated treatments with decreased total dose, does not increase overall survival

    M6P/IGF2R loss of heterozygosity in head and neck cancer associated with poor patient prognosis

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    BACKGROUND: The mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R) encodes for a multifunctional receptor involved in lysosomal enzyme trafficking, fetal organogenesis, cytotoxic T cell-induced apoptosis and tumor suppression. The purpose of this investigation was to determine if the M6P/IGF2R tumor suppressor gene is mutated in human head and neck cancer, and if allelic loss is associated with poor patient prognosis. METHODS: M6P/IGF2R loss of heterozygosity in locally advanced squamous cell carcinoma of the head and neck was assessed with six different gene-specific nucleotide polymorphisms. The patients studied were enrolled in a phase 3 trial of twice daily radiotherapy with or without concurrent chemotherapy; median follow-up for surviving patients is 76 months. RESULTS: M6P/IGF2R was polymorphic in 64% (56/87) of patients, and 54% (30/56) of the tumors in these informative patients had loss of heterozygosity. M6P/IGF2R loss of heterozygosity was associated with a significantly reduced 5 year relapse-free survival (23% vs. 69%, p = 0.02), locoregional control (34% vs. 75%, p = 0.03) and cause specific survival (29% vs. 75%, p = 0.02) in the patients treated with radiotherapy alone. Concomitant chemotherapy resulted in a better outcome when compared to radiotherapy alone only in those patients whose tumors had M6P/IGF2R loss of heterozygosity. CONCLUSIONS: This study provides the first evidence that M6P/IGF2R loss of heterozygosity predicts for poor therapeutic outcome in patients treated with radiotherapy alone. Our findings also indicate that head and neck cancer patients with M6P/IGF2R allelic loss benefit most from concurrent chemotherapy
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