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991.
992.
PURPOSE: Chemotherapy for operable breast cancer decreases the risk of death. Docetaxel is one of the most active agents in breast cancer, but resistance or incomplete response is frequent. PATIENTS AND METHODS: Core biopsies from 24 patients were obtained before treatment with neoadjuvant docetaxel (four cycles, 100 mg/m(2) every 3 weeks), and response was assessed after chemotherapy. After 3 months of neoadjuvant chemotherapy, surgical specimens (n = 13) were obtained, and laser capture microdissection (LCM; n = 8) was performed to enrich for tumor cells. From each core, surgical, and LCM specimen, sufficient total RNA (3 to 6 microg) was extracted for cDNA array analysis using the Affymetrix HgU95-Av2 GeneChip (Affymetrix, Santa Clara, CA). RESULTS: From the initial core biopsies, differential patterns of expression of 92 genes correlated with docetaxel response (P = .001). However, the molecular patterns of the residual cancers after 3 months of docetaxel treatment were strikingly similar, independent of initial sensitivity or resistance. This relative genetic homogeneity after treatment was observed in both LCM and non-LCM surgical specimens. The residual tumor after treatment in tumors that were initially sensitive indicates selection of a residual and resistant subpopulation of cells. The gene expression pattern was populated by genes involved in cell cycle arrest at G(2)M (eg, mitotic cyclins and cdc2) and survival pathways involving the mammalian target of rapamycin. CONCLUSION: A specific and consistent gene expression pattern was found in residual tumors after docetaxel treatment. These profiles provide therapeutic targets that could lead to improved treatment.  相似文献   
993.
PURPOSE: To evaluate response rate and toxicity of irinotecan and oxaliplatin plus fluorouracil (FU) and leucovorin (Folfirinox) in advanced pancreatic adenocarcinoma (APA). PATIENTS AND METHODS: Chemotherapy-naive patients with histologically proven APA and bidimensionally measurable disease were treated with Folfirinox therapy every 2 weeks, which comprised oxaliplatin 85 mg/m(2) and irinotecan 180 mg/m(2) plus leucovorin 400 mg/m(2) followed by bolus FU 400 mg/m(2) on day 1, then FU 2,400 mg/m(2) as a 46-hour continuous infusion. Quality of life (QOL) was assessed using European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 (EORTC QLQ-C30). RESULTS: Forty-seven patients were entered, and 46 received treatment. Thirty-five patients (76%) had metastatic disease. A total of 356 cycles were delivered, with a median of eight cycles per patient (range, one to 24 cycles). All patients were assessable for safety. No toxic death occurred. Grade 3 to 4 neutropenia occurred in 52% of patients, including two patients with febrile neutropenia. Other relevant toxicities included grade 3 to 4 nausea (20%), vomiting (17%), and diarrhea (17%) and grade 3 neuropathy (15%; Levi's scale). The confirmed response rate was 26% (95% CI, 13% to 39%), including 4% complete responses. Median time to progression was 8.2 months (95% CI, 5.3 to 11.6 months), and median overall survival was 10.2 months (95% CI, 8.1 to 14.4 months). Between baseline and end of treatment, patients had improvement in all functional scales of the EORTC QLQ-C30, except cognitive functioning. Responders had major improvement in global QOL. CONCLUSION: With a good safety profile, a promising response rate, and an improvement in QOL, Folfirinox will be further assessed in a phase III trial.  相似文献   
994.
995.
Thrombomodulin: tumour biology and prognostic implications.   总被引:1,自引:0,他引:1  
BACKGROUND: Thrombomodulin (TM) is an endothelial receptor that exerts anti-coagulant, anti-fibrinolytic, and anti-inflammatory activity by inhibiting thrombin and cellular adhesion. There is growing evidence that TM plays a role in tumour behaviour. METHODS: The electronic literature (1966-2004) was reviewed with a specific focus on tumour biology. RESULTS: TM is expressed on both the endothelium and tumour cells in several cancers. Loss of expression denotes a more malignant profile with poorer prognosis. Loss of TM is mediated by hypoxia, endotoxin, and various cytokines, while up-regulation can be achieved by pharmacological manipulation (e.g. pentoxyfylline and statins). CONCLUSION: Originally described as an endothelial anticoagulant, TM plays a key role in tumour biology and prognostics, and provides a potential therapeutic target in impeding cancer spread.  相似文献   
996.
PURPOSE: To evaluate academic and behavioral outcome in radiated survivors of posterior fossa (PF) tumors. PATIENTS AND METHODS: Fifty-three patients (36 males) treated for malignant PF tumors were seen for evaluation of academics and/or behavioral functioning. Forty-six patients were treated for medulloblastoma, and seven patients were treated for ependymoma. Fourteen patients were treated with reduced-dose cranial radiation, and 34 patients were treated with standard-dose cranial radiation (dose was not available for four patients). All patients received an additional boost to the PF. One patient was treated with PF radiation only. Standardized achievement tests and behavioral questionnaires were administered at different times after diagnosis for each child. First, the influence of demographic and medical variables on outcome was examined. Second, the rate of change in scores was determined using mixed model regression for patients seen for serial assessment. RESULTS: The presence of hydrocephalus was related to poorer academics, but outcome was not related to radiation dose, extent of surgery, or treatment with chemotherapy. Younger age predicted poor reading ability and lower parent rating of academic achievement. Children's performance declined for spelling, mathematics, and reading. Significant declines were also evident in parent and teacher's ratings of academic ability. Behavioral functioning was generally not related to medical and demographic variables, and few clinically significant problems in externalizing behavior were evident. Increases in social and attention problems emerged over time. CONCLUSION: Cranial radiation is associated with declines in academic ability, social skills, and attention. However, neither psychological distress nor behavior problems were a significant concern for this sample.  相似文献   
997.
PURPOSE: Biliary cancer has a poor prognosis, and chemotherapy has had little impact. The objectives of this trial were to determine the response rate, time to disease progression, survival, and safety profile of the combination of gemcitabine and capecitabine (GemCap) in patients with advanced biliary cancer. PATIENTS AND METHODS: Eligible patients had pathologically proven, locally advanced or metastatic adenocarcinoma arising from the intra- and extrahepatic bile ducts or gallbladder with no prior chemotherapy. Patients were treated on a 3-week cycle consisting of capecitabine at 650 mg/m(2) orally twice a day for 14 days and gemcitabine at a fixed dose of 1,000 mg/m(2) intravenously over 30 minutes on days 1 and 8. RESULTS: Forty-five patients were enrolled between July 2001 and January 2004. Fifty-three percent of patients had cholangiocarcinoma, 47% had gallbladder cancer, and 89% had metastatic disease. The overall objective response rate was 31%, with an additional 42% of patients with stable disease, for a disease control rate of 73%. The median overall survival time was 14 months (95% CI, 7.3 months to not available), and the median progression-free survival time was 7 months (95% CI, 4.6 to 11.8 months). This chemotherapy combination was generally well tolerated. Transient neutropenia, thrombocytopenia, fatigue, and hand-foot syndrome were commonly observed but were easily managed without discontinuing further treatment. CONCLUSION: The significant antitumor activity combined with a mild toxicity profile seen in this study argue that GemCap chemotherapy may benefit patients with advanced biliary cancer. This regimen warrants further evaluation in a randomized study with survival and quality of life end points.  相似文献   
998.
PURPOSE: YKL-40 is a secreted protein that has been reported to be overexpressed in epithelial cancers and gliomas, although its function is unknown. Previous data in a smaller sample set suggested that YKL-40 was a marker associated with a poorer clinical outcome and a genetically defined subgroup of glioblastoma. Here we test these findings in a larger series of patients with glioblastoma, and in particular, determine if tumor YKL-40 expression is associated with radiation response. EXPERIMENTAL DESIGN: Patients (n=147) with subtotal resections were studied for imaging-assessed changes in tumor size in serial studies following radiation therapy. An additional set (n=140) of glioblastoma patients who underwent a gross-total resection was tested to validate the survival association and extend them to patients with minimal residual disease. RESULTS: In the subtotal resection group, higher YKL-40 expression was significantly associated with poorer radiation response, shorter time to progression and shorter overall survival. The association of higher YKL-40 expression with poorer survival was validated in the gross-total resection group. In multivariate analysis with both groups combined (n = 287), YKL-40 was an independent predictor of survival after adjusting for patient age, performance status, and extent of resection. YKL-40 expression was also compared with genetically defined subsets of glioblastoma by assessing epidermal growth factor receptor amplification and loss at chromosome 10q, two of the common recurring aberrations in these tumors, using fluorescent in situ hybridization. YKL-40 was significantly associated with 10q loss. CONCLUSIONS: The findings implicate YKL-40 as an important marker of therapeutic response and genetic subtype in glioblastomas and suggest that it may play an oncogenic role in these tumors.  相似文献   
999.
Integrin-linked kinase (ILK) facilitates signal transduction between extracellular events and important intracellular survival pathways involving protein kinase B/Akt. We examined the role of ILK in determining pancreatic adenocarcinoma cellular chemoresistance to the nucleoside analogue gemcitabine. Cellular ILK expression was quantified by Western blot analysis. We examined the effects of overexpression of active ILK and of ILK knockdown induced by RNA interference on gemcitabine chemoresistance. We also examined the effects of modulating ILK expression on gemcitabine-induced caspase 3-mediated apoptosis, phosphorylation status of Akt (Ser473) and glycogen synthase kinase. Overexpression of ILK increased cellular gemcitabine chemoresistance, whereas ILK knockdown induced chemosensitization via increased caspase 3-mediated apoptosis. ILK knockdown attenuated Akt Ser473 and glycogen synthase kinase phosphorylation, whereas overexpression of constitutively active myristoylated Akt was sufficient to induce significant recovery in gemcitabine chemoresistance in the presence of ILK knockdown. Levels of ILK expression affect gemcitabine chemoresistance in pancreatic adenocarcinoma cells. This novel finding suggests that therapies directed against ILK and its downstream signaling targets may have the potential to enhance the efficacy of gemcitabine-based chemotherapy.  相似文献   
1000.
PURPOSE: Renal cancer response to interleukin 2 (IL-2) therapy and patient survival has been correlated with tumor histology and carbonic anhydrase IX (CAIX) expression. In an effort to confirm and expand these observations, we examined CAIX expression in pathology specimens from renal cancer patients who had previously received IL-2 therapy. EXPERIMENTAL DESIGN: Paraffin-embedded tissue sections of renal cancer were immunostained with the MN-75 monoclonal antibody to CAIX and expression levels were correlated with histologic findings and clinical outcome. RESULTS: Tissue specimens were obtained from 66 patients; 27 of whom (41%) had responded to IL-2-based therapy. Fifty-eight specimens were assessed as clear cell, with 56, 33, and 4 having alveolar, granular, and papillary features, respectively. Twenty-four (36%), 31 (47%), and 11 (17%) were classified into good, intermediate, and poor prognosis groups according to the Upton pathology model. Forty-one specimens (62%) had high CAIX expression. Twenty-one of 27 (78%) responding patients had high CAIX expressing tumors compared with 20 of 39 (51%) nonresponders (odds ratio, 3.3; P = 0.04). Median survival was prolonged (P = 0.04) and survival >5 years was only seen in high CAIX expressers. In patients with intermediate pathologic prognosis, all nine responders had high CAIX expression versus 11 of 22 nonresponders. A resultant group with good pathologic prognosis alone or with intermediate pathologic prognosis and high CAIX contained 26 of 27 (96%) responders compared with 18 of 39 (46%) nonresponders (odds ratio, 30; P < 0.01) and exhibited longer median survival (P < 0.01). CONCLUSIONS: CAIX expression seems to be an important predictor of outcome in renal cell carcinoma patients receiving IL-2-based therapy and may enhance prognostic information obtained from pathology specimens.  相似文献   
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