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101.
102.
OBJECTIVE: Tyrosine kinase with immunoglobulin and epidermal growth factor homology domains (Tie-1) is a receptor tyrosine kinase that regulates angiogenesis and antiapoptotic survival signaling. Tie-1 expression is generally associated with endothelial cells and neovascularization. We previously identified Tie-1 in human breast tumor samples using a PCR-based screen for protein kinases expressed in breast tumors. The purpose of this study was to determine the cell types expressing Tie-1, whether Tie-1 is expressed in tumor cells, and to examine the regulation of Tie-1 in breast cancer. METHODS: Tie-1 expression was analyzed by Western blot and immunohistochemistry using an antibody to the carboxy terminus of Tie-1. Tie-1 expression was determined in a variety of cancer cell lines, clinical breast and colon tumor samples, and in corresponding benign tissue from the same patient. Tie-1 expression and distribution in breast tumors was scored by immunohistochemistry. RESULTS: Tie-1 was overexpressed in 14/23 breast tumors compared with 0/9 corresponding normal tissues from the same patients. Immunohistochemistry revealed that Tie-1 was overexpressed in epithelial breast cancer cells and ductal carcinoma in situ. In all breast tumor samples, Tie-1 was expressed as a truncated 40- to 43-kD doublet consisting of the intracellular portion of the protein, which contains the tyrosine kinase catalytic domain. The 40- to 43-kD Tie-1 doublet was expressed in a broad variety of cell lines. CONCLUSIONS: We have shown that breast cancer cells overexpress a cleaved form of the Tie-1 protein. Our results implicate the intracellular domain of Tie-1, which includes the catalytic kinase domain, in breast cancer progression.  相似文献   
103.
PURPOSE: The purpose of this study was to establish the feasibility and efficacy of preoperative radiotherapy (RT) with concurrent capecitabine and oxaliplatin (XELOX-RT) in patients with rectal cancer. PATIENTS AND METHODS: Thirty-two patients with locally advanced (T3/T4) or low-lying rectal cancer received preoperative RT (total dose, 50.4 Gy). Capecitabine was administered concurrently at 825 mg/m2 bid on days 1 to 14 and 22 to 35, with oxaliplatin starting at 50 mg/m2 on days 1, 8, 22, and 29 with planned escalation steps of 10 mg/m2. End points of the phase II study included downstaging, histopathologic tumor regression, resectability of T4 disease, and sphincter preservation in patients with low-lying tumors. RESULTS: Dose-limiting grade 3 gastrointestinal toxicity was observed in two of six patients treated with 60 mg/m2 of oxaliplatin. Thus, 50 mg/m2 was the recommended dose for the phase II study. Toxicities observed at this dose level were generally mild, with only two cases of short-lived grade 3 diarrhea. Myelosuppression, mainly leukopenia, was restricted to grade 2 in 19% of patients. T-category downstaging was achieved in 17 (55%) of 31 operated patients, and 68% of patients had negative lymph nodes. Pathologic complete response was found in 19% of the resected specimens. Radical surgery with free margins could be performed in 79% of patients with T4 disease, and 36% of patients with tumors < or = 2 cm from the dentate line had sphincter-saving surgery. CONCLUSION: Preoperative XELOX-RT is a feasible and well tolerated treatment. This regimen is proposed for phase III evaluation comparing standard fluorouracil-based therapy with XELOX chemoradiotherapy.  相似文献   
104.
PURPOSE: To investigate whether the nasal route for fentanyl administration in patient-controlled analgesia (PCA) provides as effective postoperative analgesia as intravenous PCA. METHODS: Patient-controlled intranasal or intravenous analgesia with fentanyl was investigated in 48 patients (ASA I-III) on the day of surgery (orthopedic, abdominal or thyroid) in a prospective, randomized, double-blind, double-dummy study. Fentanyl was given in a bolus of 25 microg for intranasal and 17.5 microg for i.v. PCA, lockout interval six minutes. The first requested dose was doubled in both groups. Pain intensity (101-point numerical rating scale) and vital parameters were observed at 11 measurement points during the 240 min study. Patients were asked for side effects at every measurement point and for their satisfaction at the end of the study by the same investigator (J.M.). RESULTS: Onset of analgesia, the first reduction in pain intensity on the numerical rating scale, was 21 +/- 11 min (range 15-45 min) in intranasal and 22 +/- 16 min (range 15-90 min) in i.v. PCA. Pain intensity was reduced from 55 +/- 11 to 11 +/- 10 in the intranasal group and from 53 +/- 8 to 11 +/- 6 in the i.v. PCA group. Vital parameters remained stable and side effects were comparable in both groups. The judgement "excellent" or "good" was given by 21 of 23 patients treated intranasally and 24 of 25 patients treated intravenously. CONCLUSION: Intranasal PCA with fentanyl was an effective alternative to i.v. PCA in postoperative patients.  相似文献   
105.
PURPOSE: In recent studies, we showed that TP53 gene mutation or high levels of cytosolic vascular endothelial growth factor (VEGF) in estrogen receptor (ER)-alpha-positive primary breast tumors predict a poor disease outcome for patients treated with first-line tamoxifen for advanced disease. Mutant TP53 may up-regulate VEGF, whereas, on the other hand, wild-type TP53 may decrease VEGF production. EXPERIMENTAL DESIGN: In the present study, we aimed to assess the combined predictive value of TP53 gene mutation and VEGF status of 160 advanced breast cancer patients with ER-positive tumors who were treated with tamoxifen (median follow-up from start of tamoxifen treatment, 64 months). To assess TP53 gene mutation status, the entire open reading frame was sequenced; for VEGF status, an ELISA was used. RESULTS: In univariate analysis, both TP53 gene mutation (28% of the tumors) and a VEGF level above the median value were significantly associated with a short progression-free survival, post-relapse overall survival, and a poor rate of response to tamoxifen. In Cox multivariate regression analysis including the traditional predictive factors, the addition of TP53 gene mutation and VEGF status, alone or in combination, significantly predicted a poor efficacy of tamoxifen treatment. When the two factors were combined, a significantly decreased odds ratio was seen for the rate of response (odds ratio, 0.27). Similarly, an increased hazard ratio (HR) was seen for progression-free survival (HR, 2.32) and post-relapse overall survival (HR, 1.68) in the group with mutant TP53 and high VEGF compared with the group with both risk factors absent. CONCLUSIONS: Combined TP53 gene mutation status and high VEGF levels of ER-positive primary breast tumors independently predict a poor course of the disease of patients with advanced breast cancer treated with tamoxifen. These patients, having unfavorable tumor characteristics, might benefit more from other types of (individualized) treatment protocols.  相似文献   
106.
PURPOSE: To prospectively assess potential risk factors for relapse in clinical stage I nonseminomatous germ cell tumors of the testis (CS I NSGCT). PATIENTS AND METHODS: From September 1996 to May 2002, 200 patients with CS I NSGCT were prospectively assigned to retroperitoneal lymph node dissection (RPLND), and risk factor assessment was performed within a multicenter protocol. One hundred sixty-five patients had an adequate minimum follow-up of 12 months (mean, 34.5 months) or had pathologic stage II. RESULTS: Pathologic stage II disease was found in 27.9% of patients. Only 0.6% of patients relapsed in the retroperitoneum after confirmation of pathologic stage I disease. With reference pathology, vascular invasion (VI) was most predictive of stage in multifactorial analysis (accuracy, 65.1%). However, the positive predictive value (PPV) of VI to predict patients who have metastatic disease or relapse during follow-up was only 52.7%. With absent VI, low-risk patients had a negative predictive value (NPV) of 76.9%. With a combination of several risk factors, the PPV increased to 63.6% and the negative predictive value increased to 86.5%. CONCLUSION: Even with an optimal combination of prognostic factors and reference pathology, more than one third of patients predicted to have pathologic stage II or relapse during follow-up will not harbor metastatic disease and, therefore, would be overtreated with adjuvant therapy. However, patients at low risk may be predicted at an 86.5% level, and thus, surveillance in highly compliant patients would be a valuable option. For high-risk patients, further reduction of adjuvant treatment is necessary.  相似文献   
107.
A noninvasive system designed for patient tracking during image-guided intranasal sinus surgery is described. It is based on optical digitizing with a custom-made registration and reference system, locatable surgical instruments, and a self-localizing operating microscope. Experimental and clinical results reveal a high degree of accuracy for the system. A mean spatial error of 0.82 ± 0.31 mm was determined for repositioning of the reference system in a plastic model of the skull. For the positioning of the microscope, a mean error of 2.3 ± 0.83 mm was calculated. Measurements of repositioning accuracy in 24 patients who received surgery for various sinus diseases had a mean spatial error of 1.56 ± 0.76 mm. The 95% error interval for locating intranasal structures using the surgical instrument was 2.05 mm, and it was 4.92 mm using the microscope. These results suggest that the use of our noninvasive registration and reference system may be effective, accurate, and useful for noninvasive tracking of patient movements in computer-assisted intranasal surgery.  相似文献   
108.
A retrospective review is presented of 1353 consecutivepatients with histopathologically confirmed invasive breast carcinoma treatedradically with curative intent during the decade 1980–89.None had received adjuvant systemic therapy with hormonesor prolonged chemotherapy. The distribution of lymph-node negative(N–) and lymph-node positive (N+) patients was 75%and 25%, respectively.The treatment and outcome were analysed as regardsconventional prognostic parameters, in particular considering the axillarylymph-node status and the responsible hospital category (GeneralMunicipal Hospitals (MH)) versus Comprehensive Cancer Center (CC)).The most striking difference was detected as regardsthe number of examined lymph nodes. The mediannumber of nodes described at the MH was7, as compared to 14 at the CC(p < 0.001). In patients with pT1 tumoursthe highest rate of lymph-node positivity was observedwhen 10 or more axillary nodes were removed.Adjuvant radiotherapy reduced the loco-regional recurrence rate inthe N– patients, whereas only the regional recurrenceswere reduced among the N+ patients. The five-and 10-year tumor-related survival rates were 86% and76%, respectively, with no difference between the MHand the CC.As life-prolonging adjuvant hormone therapy and chemotherapy isnow available for patients with axillary lymph nodemetastases, it is important that patients with breastcancer are operated adequately with the aim toremove at least 10 axillary lymph nodes. Athorough examination of the axillary content should beperformed by the pathologist, and the number ofresected lymph nodes and metastases should be reported.The establishment of nation-wide standard criteria for themanagement of breast cancer is recommended.  相似文献   
109.
Imatinib mesylate (GLEEVEC, GLIVEC, formerly STI571) has demonstrated unprecedented efficacy as first-line therapy for treatment for all phases of chronic myelogenous leukemia and metastatic and unresectable malignant gastrointestinal stromal tumors. Disposition and biotransformation of imatinib were studied in four male healthy volunteers after a single oral dose of 239 mg of (14)C-labeled imatinib mesylate. Biological fluids were analyzed for total radioactivity, imatinib, and its main metabolite CGP74588. Metabolite patterns were determined by radio-high-performance liquid chromatography with off-line microplate solid scintillation counting and characterized by liquid chromatography-mass spectrometry. Imatinib treatment was well tolerated without serious adverse events. Absorption was rapid (t(max) 1-2 h) and complete with imatinib as the major radioactive compound in plasma. Maximum plasma concentrations were 0.921 +/- 0.095 mug/ml (mean +/- S.D., n = 4) for imatinib and 0.115 +/- 0.026 mug/ml for the pharmacologically active N-desmethyl metabolite (CGP74588). Mean plasma terminal elimination half-lives were 13.5 +/- 0.9 h for imatinib, 20.6 +/- 1.7 h for CGP74588, and 57.3 +/- 12.5 h for (14)C radioactivity. Imatinib was predominantly cleared through oxidative metabolism. Approximately 65 and 9% of total systemic exposure [AUC(0-24 h) (area under the concentration time curve) of radioactivity] corresponded to imatinib and CGP74588, respectively. The remaining proportion corresponded mainly to oxidized derivatives of imatinib and CGP74588. Imatinib and its metabolites were excreted predominantly via the biliary-fecal route. Excretion of radioactivity was slow with a mean radiocarbon recovery of 80% within 7 days (67% in feces, 13% in urine). Approximately 28 and 13% of the dose in the excreta corresponded to imatinib and CGP74588, respectively.  相似文献   
110.
OBJECTIVE: Hpr6 (heme-1 domain protein/human progesterone receptor) is one of a family of proteins that are implicated in progesterone metabolism, resistance to genotoxic agents and steroid biosynthesis. Because these processes are frequently misregulated in tumors, we have examined the expression of Hpr6 in a group of clinical tumor samples and cancer cell lines. METHODS: Hpr6 expression was analyzed by Western blot in extracts from breast, cervix, colon and thyroid cell lines and in nonmalignant and adjacent tumor tissue from breast, colon and thyroid. Hpr6 localization was determined by immunofluorescence. RESULTS: Hpr6 expression is significantly elevated in breast tumors in comparison with matched nonmalignant tissue and demonstrated limited overexpression in colon and thyroid tumors. Hpr6 is strongly expressed in a panel of tumor cell lines originating from breast, thyroid and colon. Hpr6 localizes to the perinuclear region of the cell, consistent with a role in cell detoxification, signaling and/or sterol synthesis. CONCLUSIONS: Hpr6 homologues regulate cytochrome P450 proteins implicated in hormone, steroid and xenobiotic chemical metabolism. These are the first studies linking Hpr6 expression to cancer progression and cellular survival. Our results suggest that Hpr6 is an important marker for cancer progression and a potential anticancer therapeutic target.  相似文献   
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