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941.
BACKGROUND: Glucose transporter (Glut) proteins, which are membrane proteins responsible for the transport of glucose across cellular membranes, have six forms. To further elucidate the role of Glut-1 expression in esophageal squamous cell carcinoma, we examined the expression of Glut-1 protein immunohistochemically. MATERIALS AND METHODS: Immunohistochemical expression of Glut-1 was examined in surgically resected tissues from 95 patients with esophageal squamous cell carcinoma. RESULTS: Of the 95 esophageal carcinomas, 91 (95.8%) had some Glut-1 immunostaining in the membranes of the cancer cells. Positive staining (> 30% of cancer cells showing Glut-1 expression) was observed in 49 (51.6%) of the cases. Comparison of Glut-1 expression and clinicopathological characteristics in the 95 patients with esophageal cancer revealed significant associations between Glut-1 expression and tumor status (p < 0.001), lymph node status (p < 0.05), metastatic status (p < 0.01), and pathological stage (p < 0.001). The survival rates of patients with Glut-1-positive tumors were significantly lower than those of patients with Glut-1-negative tumors (log-rank p < 0.05). CONCLUSION: In conclusion, the level of Glut-1 expression may be a useful marker that can provide information on tumor aggressiveness and prognosis in patients with esophageal squamous cell carcinoma.  相似文献   
942.
BACKGROUND: The roles of urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) in the formation of macroscopic types and invasion were investigated. MATERIALS AND METHODS: A total of 40 surgically-resected esophageal carcinoma tissues were immunohistochemically stained, and the expression of uPA, PAI-1 and the uPA/PAI-1 ratio, were evaluated. RESULTS: The expression of uPA was significantly stronger in the macroscopically infiltrative type (n = 20: p = 0.0027), whereas PAI-1 was significantly stronger in the localized type (n = 20: p = 0.0005). The uPA/PAI-1 ratio was significantly higher in the infiltrative type (p < 0.0001). A significant correlation was found between the U/P ratio and the depth of tumor invasion (r = 0.511, p = 0.0014). Analysis of tumors of uniform size (4.0-6.0 cm in length), showed that the depth of invasion was significantly greater in the infiltrative type (p = 0.0038). CONCLUSION: The results demonstrated that uPA and PAI-1 play important roles in invasion and formation of macroscopic types of esophageal carcinoma.  相似文献   
943.
We have shown that a soluble receptor for vascular endothelial growth factor (sVEGFR), which adsorbs VEGF and may function as a dominant-negative receptor, suppresses tumor angiogenesis and enhances apoptosis of cancer cells, thereby inhibiting tumor growth [Cancer Res 60 (2000) 2169-2177]. In the present study, using as many as 11 cancer cell lines, we tested two hypotheses: (a) that a soluble fibroblast growth factor receptor-1 (sFGFR1) might inhibit tumor angiogenesis and growth in sVEGFR-resistant cancers, and (b) that combining sFGFR1 with sVEGFR might produce an enhanced inhibitory effect. In two cell lines derived from human lung cancer, H460 and A549, both of which produce a considerable amount of FGF-2, sVEGFR and a soluble receptor for angiopoietin-1 were both ineffective; however, sFGFR1 inhibited tumor angiogenesis and growth, demonstrating the critical role that FGFs play in some cancers. In three cell lines (QG56 from lung cancer, T3M4 and Panc1 from pancreatic cancer), which produced both VEGF and FGF-2 at detectable levels, combined sVEGFR and sFGFR1 produced an enhanced inhibitory effect compared to their individual effects. The combined usage of sVEGFR plus sFGFR1 suppressed tumor growth in all cancer cell lines tested, suggesting possible effectiveness of this strategy against a wide range of cancers.  相似文献   
944.
945.
Doxorubicin enhances TRAIL-induced apoptosis in prostate cancer   总被引:4,自引:0,他引:4  
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in various tumor cells. The anthracycline doxorubicin (DOX) can sensitize several types of cancer cells to TRAIL-mediated apoptosis. Here we report that DOX enhances TRAIL-induced apoptosis and cytotoxicity against prostate cancer cells. Cytotoxicity was determined by a MTT assay. Synergistic effect was assessed by isobolographic analysis. Caspase activity was determined by a quantitative colorimetric assay. The combination treatment with DOX and TRAIL resulted in a synergistic cytotoxic effect on LNCaP, LNCaP-Bcl-2, PC-3, and PC93 human prostate cancer cell lines, but not on normal human prostatic stromal cells. Synergistic cytotoxicity was also obtained even when the exposure time was shortened from 24 to 8 or 2 h. A similar effect was achieved with TRAIL in combination with epirubicin, pirarubicin, or amrubicin. The synergy obtained in cytotoxicity with TRAIL and DOX was also achieved in apoptosis. DOX treatment significantly activated caspase-8, -6, and -3 in LNCaP cells. Furthermore, the synergistic cytotoxicity of TRAIL and DOX was completely inhibited by Z-VAD-FMK, and partly inhibited by Ac-IETD-CHO, Ac-DQTD-CHO, or Ac-DMQD-CHO. These findings indicate that DOX enhances TRAIL-induced apoptosis and cytotoxicity in prostate cancer by activation of caspase cascades, and suggest that TRAIL in combination with DOX have a therapeutic potential in the treatment of prostate cancer.  相似文献   
946.
An elderly patient with breast cancer received toremifene monotherapy for one year, and about 60% tumor remission rate was obtained. Since viability of the residual tumor was suspected on ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI), lumpectomy was performed under local anesthesia. The histopathological diagnosis was ductal carcinoma in situ (DCIS). The patient did not undergo axillary lymph node dissection or systemic chemotherapy. The patient is alive without disease under postoperative radiotherapy and toremifene treatment. Toremifene monotherapy and/or preoperative adjuvant therapy with toremifene alone may be useful methods for elderly patients with breast cancer considering the patients' quality of life.  相似文献   
947.
Deep-seated gliomas, including thalamic gliomas, have a poor prognosis because of difficulty of accessibility for surgery. In addition, an infiltrative pattern of the tumor is related to a poor prognosis. In this study, the infiltrative/invasive profile of the proliferating tumor cells of a right thalamic glioma was evaluated in an autopsied brain. A 71-year-old man died from extensive infiltration of a right thalamic glioma. The distribution of the proliferating tumor cells at the right thalamic tumor level was represented by the topographic map of MIB-1 labeling indices (LI) on the whole-brain coronal slice, and this map was analyzed with pathological findings and postmortem T2-weighted magnetic resonance imaging (MRI). The highest MIB-1 LI was 24% for the whole autopsy brain at the thalamic tumor level, whereas the MIB-1 LI was 21% for the biopsy sample of the right thalamic glioma. Because this patient survived only 9 months after diagnosis of the tumor as anaplastic astrocytoma, it was confirmed that 21% MIB-1 LI of the biopsy sample was relevant to his prognosis. The topographic map of MIB-1 LI showed that the proliferating tumor cells of the right thalamic glioma invaded the ventricular walls and the contralateral thalamus by the periventricular route, but there was no exophytic extension to the cortex. In conclusion, topographic analysis of the proliferative potential detected by MIB-1 immunostaining provides information on the growth pattern of human glioma.  相似文献   
948.
949.
BACKGROUND: Brain metastases from esophageal carcinoma are extremely rare, and information regarding the natural history, results of treatment, and possible prognostic factors in these patients is limited. METHODS: The records of 36 patients with brain metastases from esophageal carcinoma who were treated between 1986 and 2000 were reviewed. For brain metastases, 12 patients (33%) were treated with surgical resection followed by radiation therapy (S+RT), and the remaining 24 patients were treated with radiation therapy alone. RESULTS: At the initial diagnosis of esophageal carcinoma, the median primary tumor length was 8 cm (range, 2-19 cm), and 26 of 32 available patients (81%) had clinical Stage III-IV tumors according to the International Union Against Cancer 1997 criteria. At time brain metastases appeared, lung metastases were not demonstrated in 25 of 36 patients (69%) who were assessed by chest computed tomography (CT) scans. The overall median survival for all patients was 3.9 months (range, 0.6-36.8 months), and the actuarial survival rates at 12 months and 24 months were 14% and 3%, respectively. In univariate analysis, treatment modality, Karnofsky performance status (KPS), and extracranial disease status each had a statistically significant impact on survival, and, in multivariate analysis, treatment modality and KPS were statistically significant prognostic factors for survival. Five patients (14%) survived more than 1 year, all of whom were treated with S+RT. These five patients had inactive extracranial disease and, four of five patients (80%) had a 90-100% KPS. CONCLUSIONS: Brain metastases from esophageal carcinoma tended to occur in patients with a large primary tumors and/or disease in advanced clinical stages. With the appearance of brain metastases, an absence of lung metastasis frequently was observed on chest CT scans. The prognoses for these patients were generally poor, although selected patients may survive longer with intensive brain tumor treatment.  相似文献   
950.
We treated a lower rectal carcinoma patient with preoperative radiation and chemotherapy, resulting in a downstaging, and the findings are reported herein. The patient is a 55-year-old woman endoscopically diagnosed with advanced rectal carcinoma at a site 3 cm from the dental line. Preoperative radiation and chemotherapy included whole pelvis irradiation (44 Gy in total) and 800 mg/day of 5'-DFUR administered until one day before the operation. On the 20th day after completing irradiation, a low anterior resection of the rectum was conducted. During the operation, we found serositis of the small intestine and retroperitoneal fibrosis thought to be due to the irradiation. Histopathologic findings showed: invasion degree, sm2; stage I with N0; and histologic grading, Grade 2. The patient started drinking water from postoperative day 1, and was discharged on postoperative day 11. At present, in Europe and the USA, large scale studies are being conducted to evaluate preoperative radiation and chemotherapy in patients with lower rectal carcinoma. We think that this therapy is an effective treatment, since a distance (AW) from the lower margin of the tumor and the cut edge of the anal end can be established.  相似文献   
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