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Cancer cachexia has a significant negative effect on quality of life, survival and the response to treatment. Recent in vitro and experimental animal studies have shown that myosin may be the primary target of the muscle wasting associated with cancer cachexia. In this study, we have extended these analyses to detailed studies of regulation of myofibrillar protein synthesis at the gene level, myofibrillar protein expression and regulation of muscle contraction at the muscle cell level in a 63-year old man with a newly diagnosed small cell lung cancer and a rapidly progressing lower extremity muscle wasting and paralysis. A significant preferential loss of the motor protein myosin together with a downregulation of protein synthesis at the transcriptional level was observed in the patient with cancer cachexia. This had a significant negative impact on muscle fiber size as well as maximum force normalized to muscle fiber cross-sectional area (specific tension).

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BACKGROUND: The effect of delay on survival in lung cancer remains uncertain. It is suggested that prompt management of non-small cell lung cancer (NSCLC) can influence prognosis. This study was undertaken to examine the relation between delay and prognosis in patients with NSCLC and to investigate the delay time from first symptom and from first hospital visit to start of treatment. METHODS: Two types of delay (symptom to treatment delay and hospital delay) were investigated in 466 patients treated for NSCLC at two institutions in central Sweden. Delays in relation to clinical characteristics were compared and the effects of delay times and other relevant factors on survival were assessed in multivariate analyses. RESULTS: Thirty five per cent of patients received treatment within 4 weeks of the first hospital visit and 52% within 6 weeks. Median symptom to treatment delay was 4.6 months and median hospital delay 1.6 months. Older age, advanced tumour stage, and non-surgical treatment were independently related to poor survival. Both prolonged hospital delay and symptom to treatment delay provided additional information when considered separately. In a final multivariate model only increased symptom to treatment delay gave significant information of a better prognosis. There was an association between a short delay and a poor prognosis which was most pronounced in patients with advanced disease. CONCLUSION: When considering the whole study population and all stages of tumour together, shorter delay was associated with a poorer prognosis. This is likely to reflect the fact that patients with severe signs and symptoms receive prompt treatment. These findings indicate that the waiting time for treatment in patients with NSCLC is longer than recommended.

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We have analysed the predictive and prognostic information in preoperatively collected serum levels of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in patients clinically evaluated as operable non-small cell lung cancer (NSCLC). Fifty-eight patients with operable NSCLC were included. VEGF and bFGF levels in serum were analysed using enzyme linked immunosorbent assays (Quantikine human VEGF and Quantikine HS human FGF basic, R&D Systems). Univariate analysis demonstrated that tumour volume, platelet counts, VEGF and bFGF were significant prognostic factors. However, only bFGF remained significant in the multivariate analysis (P=0.014). Significant correlation's were demonstrated between VEGF levels and tumour volume (r=0.33; P=0.012) and platelet count (r=0.43; P=0.001). bFGF levels correlated significant with recurrent disease (r=0.34; P=0.01), platelet count (r=0.53, P<0.001) and performance status (r=0.29; P=0.029). Furthermore, bFGF levels and VEGF levels correlated significantly (r=0.44; P<0.001). We conclude that elevated circulating angiogenic cytokines correlate with tumour volume, higher relapse risk and poorer survival in patients with operable non-small cell lung cancer.

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In Escherichia coli, the anaerobic expression of genes encoding the nitrate (narGHJI) and dimethyl sulphoxide (dmsABC) terminal reductases is stimulated by the global anaerobic regulator FNR. The ability of FNR to activate transcription initiation has been proposed to be dependent on protein-protein interactions between RNA polymerase and two activating regions (AR) of FNR, FNR-AR1 and FNR-AR3. To further our understanding of the role of FNR-AR1 and FNR-AR3 in transcription activation, we measured the effects of FNR-AR mutants on expression of the narG and dmsA promoters, PnarG and PdmsA. All the FNR-AR1 (FNR-S73F, FNR-T118A, FNR-S187P), FNR-AR3 (FNR-G85A) and FNR-AR1-AR3 (FNR-G85A-S187P) mutants that were tested decreased expression from PnarG and PdmsA in vivo. Transcription assays of PdmsA also showed that the FNR-AR mutant proteins impaired transcription activation in vitro. Furthermore, DNase I footprinting analysis confirmed that this transcription defect was not a result of altered DNA-binding properties. The function of FNR-S187P and FNR-G85A was also measured in strains containing sigma70 mutants (sigma70-K593A, sigma70-R596A and sigma70-K597A) known to be impaired in FNR-dependent transcription activation. Of all of the combinations analysed, only FNR-G85 and sigma70-K597 showed a genetic interaction, supporting the notion that FNR-AR3 and sigma70 interact functionally in the process of transcription activation. Lastly, the transcription activation defect of the FNR-AR1 and FNR-AR3 mutants was greatly reduced when expression of PnarG was assayed in the presence of nitrate. As these growth conditions promote maximal activity of PnarG as a result of the combined function of NarL, IHF and FNR, these results suggest that the requirements for FNR-AR1 and FNR-AR3 are altered in the presence of additional activators.

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The primary aim of this phase II study was to determine the response rate of a combination of paclitaxel and carboplatin in advanced non-small cell lung cancer (NSCLC) in a multicentre setting. The secondary aim was to determine time to progression (TTP), 1-year survival rate and toxicity. 65 patients were treated and all of them were included in the follow up for survival and toxicity. 60 patients were followed for response rate and time to progression. 55% were stage IV patients and 45% stage IIIB patients. The treatment consisted of paclitaxel 200 mg/m2 given as a 1-h i.v. infusion and carboplatin given as a 30 min i.v. infusion and the latter was dosed by using the Calvert formula at an area under the concentration time curve (AUC) of 5. The glomerular filtration rate (GFR) was determined by iohexol clearance and was not calculated from the serum creatinine level. The chemotherapy courses were given every third week with a maximum number of six or eight courses for patients who responded late. As premedication we used 8 mg betamethasone 40 min prior to infusion and then 10 min later clemastin and cimetidine. One complete response and 18 partial responses were seen giving a response rate of 29%. 40% of the patients progressed during the treatment and 28% had stable disease. The median TTP was 22 weeks. At a minimum follow up of 1 year, the 1-year survival rate was 38% and the median survival rate was 41 weeks. Haematological toxicity was mild with no grade 4 leucopenia and only seven patients (11%) had grade 3 leucopenia. There was no grade 4 toxicity. Grade 3 toxicity was seen as myalgia 5%, allergic reaction 3% and peripheral neuropathy 6%. 15% of the patients had a dose reduction due to neurotoxicity. The haematological toxicity was much milder than we expected, probably because of more exact determination of the GFR. This trial confirms the results of earlier reported trials of the efficacy and the ease of the regimen as an out-patient treatment option in advanced NSCLC. The main problem with this treatment is peripheral neuropathy.

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UNLABELLED: We evaluated the value of PET using 18F-fluorodeoxyglucose (FDG) and 11C-methionine, individually or in combination, to distinguish malignant from benign tumors and to identify or exclude mediastinal metastases. METHODS: Seventeen patients with a tumor in the lung or mediastinum were evaluated with 18F-FDG and 11C-methionine PET. For morphological comparison, we used CT, and all findings were confirmed by histology of surgical resection specimens (n = 16) or by cytology (n = 1). RESULTS: All tumors were visualized equally well with both tracers, and there were no false-positive results. In 2 patients with a malignant tumor, coexisting pneumonia was correctly diagnosed as an inflammatory lesion because of its wedge-like shape. PET correctly excluded hilar invasion and mediastinal lymph node metastases in 10 of 14 patients with primary lung tumor. PET identified mediastinal metastases in 4 of 4 patients. CT failed to detect mediastinal tumor spread in 2 patients and gave a false-positive reading in 2 others. Significantly higher uptake (SUV) and transport rate (slope) values were obtained from malignant than benign lesions with both tracers. No major differences were seen in either the levels of significance or accuracy when the two tracers were compared. Slope values did not add further information to what was obtained with SUV. Density correction of SUV and slope values, to avoid the influence of surrounding air as well as tumor heterogeneity, increased these differences somewhat. Both tracers distinguished malignant from benign lesions with a 93% sensitivity and an accuracy of 89%-95%, but sensitivity improved to 100% when values from both tracers were combined. CONCLUSION: Fluorine-18-FDG and 11C-methionine PET visualized all tumors equally well and detected mediastinal spread better than CT. For differentiation purposes, the problems of false-positive and false-negative PET findings could not be safely overcome in a limited number of cases either by the use of both tracers, by the additional use of slope values or by lesion density correction.

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In this study the entire p53 complementary DNA has been sequenced in 20 non-small cell lung carcinomas (NSCLC) and the results correlated with chemosensitivity, immunohistochemistry and clinical data. Ten patients had mutations in p53, 8 missense mutations and 2 nonsense mutations. The method discovered two mutations never described previously and two other mutations that have never been described before in connection with NSCLC tumours. Chemosensitivity data, according to a short-term assay (FMCA), indicated that tumours with p53 mutation were more resistant to cisplatin and cyclophosphamide. Immunohistochemical studied demonstrated a 70% concordance between over-expression of p53 protein and mutation in p53. No conclusions or trends could be drawn from the immunohistochemical studies of Bcl-2 and Bax.

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The sigma subunit of RNA polymerase orchestrates basal transcription by first binding to core RNA polymerase and then recognizing promoters. Using a series of 16 alanine-substitution mutations, we show that residues in a narrow region of Escherichia coli sigma70 (590 to 603) are involved in transcription activation by a mutationally altered CRP derivative, FNR and AraC. Homology modeling of region 4 of sigma70 to the closely related NarL or 434 Cro proteins, suggests that the five basic residues implicated in activation are either in the C terminus of a long recognition helix that includes residues recognizing the -35 hexamer region of the promoter, or in the subsequent loop, and are ideally positioned to permit interaction with activators. The only substitution that has a significant effect on activator-independent transcription is at R603, indicating that this residue of sigma70 may play a distinct role in transcription initiation.

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Seventy-nine patients with small bronchial carcinoma randomly received cyclophosphamide, doxorubicin, vincristine, and methotrexate, alternating after four cycles with cyclophosphamide, lomustine, vincristine and methotrexate or the same with replacement of methotrexate by etoposide in lomustine cycles. Patients with limited disease received radiotherapy with 40 Gy. In 34 patients with extensive disease the total response in the groups with and without etoposide was 89% and 69% and the median survival 10.9 and 8.2 months respectively. In 45 patients with limited disease, the complete remission rates in the groups with and without etoposide were 57% and 67%, partial remission rates 38% and 25%, and the median survival times 12.3 and 17.8 months respectively. The disease-free survival exceeding 5 years in the respective groups was 4.2% and 14.3%. A slightly better response in extensive disease and a tendency to better long-term survival in limited disease was noted but the price was increased toxicity in the latter group.

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