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11.
BACKGROUND: Hypoxia-inducible factor 1alpha (HIF-1alpha) and HIF-2alpha are essential regulatory proteins for the adaptation of tumor cells to hypoxia, and they stimulate angiogenesis through activation of the vascular endothelial growth factor (VEGF) gene. METHODS: HIF-1alpha and HIF-2alpha proteins were studied immunohistochemically in a group of 81 patients with Stage I endometrial adenocarcinoma of the endometrioid cell type. The results were correlated with intratumoral angiogenesis, the expression of the angiogenic factors VEGF and thymidine phosphorylase (TP), and the VEGF/receptor (VEGF/KDR) complex. Relations also were sought with estrogen receptor (ER) and progesterone receptor (PR), with the apoptosis-related proteins bcl-2 and p53, with several histopathologic parameters, and with patient prognosis. In addition, a sample of 25 normal endometria at various phases of the menstrual cycle was studied for the presence of HIF-1alpha and HIF-2alpha. RESULTS: HIF-1alpha expression was detected in 49% of endometrial carcinomas. The expression was cytoplasmic or mixed nuclear/cytoplasmic. HIF-1alpha expression was associated with up-regulation of the VEGF pathway and with increased standard microvessel density (sMVD) and activated VEGF/KDR microvessel density (aMVD). It also was associated with a poor prognosis in both univariate and multivariate analyses. HIF-2alpha protein showed a pattern of expression similar to the pattern seen in HIF-1alpha, but expression of HIF-2alpha protein occurred in only 17% of endometrial carcinomas, and it was associated with increased TP reactivity. There also was a relation of HIF-1alpha expression with well-differentiated endometrial neoplasms, and there was a marginal association of HIF-1alpha and HIF-2alpha with ER expression. With reference to normally cycling tissues, HIF-1alpha nuclear/cytoplasmic expression was particularly strong in the samples of early proliferative phase endometrium compared with HIF-2alpha protein expression, which showed a constant reaction throughout the menstrual cycle. CONCLUSIONS: The up-regulation of HIF-1alpha and, to a lesser extent, of HIF-2alpha is a common event in Stage I endometrial adenocarcinomas. In these tumors, HIF-1alpha expression is related to increased angiogenesis, through activation of the VEGF angiogenic pathway, and to an unfavorable prognosis. HIF-2alpha accumulation is associated with increased expression of the angiogenic factor TP.  相似文献   
12.
Vascular endothelial growth factor (VEGF) is an important angiogenic factor, linked to poor outcome in human malignancies including non-small cell lung carcinoma (NSCLC). We used the 11B5 monoclonal antibody recognizing the VEGF/KDR complex (R. A. Brekken et al., Cancer Res., 58: 1952-1959, 1998) to assess the VEGF expression in cancer cells and the VEGF/KDR activated microvessel density (aMVD) in early operable NSCLC. The JC70 anti-CD31 monoclonal antibody was used to assess the standard MVD (sMVD). The aMVD was significantly higher in the invading front of the tumors and in the normal lung adjacent to the tumors as compared with normal lung distant to the tumor or to inner tumor areas (P < 0.0002). The sMVD was higher in the normal lung and decreased from the invading front to inner tumor areas (P < 0.0001). However, the vascular activation (aMVD:sMVD) was 4-6 times higher in the tumor areas as compared with lung from normal individuals (36-58% versus 9%; P < 0.0001). Fibroblast 11B5 reactivity, noted in 25% of cases, correlated with high aMVD and sMVD in the inner tumor areas. Multivariate analysis showed that aMVD was the most potent and independent prognostic factor (P = 0.001; t-ratio, 3.28). It is concluded that intense VEGF/KDR angiogenic pathway activation is a tumor-specific feature in more than 50% of NSCLC cases and is associated with poor postoperative outcome. Clinical trials involving targeting of the VEGF/KDR-positive vasculature with specific antibodies, such as 11B5, are, therefore, encouraged.  相似文献   
13.
Sarcomas are radioresistant tumors, the only curative therapy being radical surgical resection. Stealth liposomal doxorubicin (Caelyx) is a novel drug formulation that allows prolonged circulation and high intratumoral concentration. This study investigates the concurrent use of radiotherapy with Caelyx in a cohort of 7 patients with locally advanced or recurrent sarcoma. Radiotherapy was given as a standard fractionation regimen to a total dose of 70 Gy. Caelyx was given as a 30-min infusion at a dose of 25 mg/m2 every 2 weeks. Scintigraphic imaging with Caelyx-99mTc-DTPA showed an increased (2.8 +/- 0.9 times higher) intratumoral drug accumulation compared to the surrounding healthy tissue. The regimen was well tolerated without any severe hematological or systemic toxicity. 'In field' radiation toxicity was not increased. Complete response was observed in 4/7 cases. It is concluded that combined chemo-radiotherapy with stealth liposomal doxorubicin for locally advanced sarcomas is feasible and promising, the benefit expected from the unique ability of the stealth liposomes to accumulate selectively in the tumoral tissue.  相似文献   
14.
PURPOSE: Photodynamic therapy (PDT) has shown remarkable activity in a variety of human cancers. In the present study, we report the effects of PDT on inoperable early-stage esophageal cancer. METHODS AND MATERIALS: Sixty-two patients were treated with an argon dye laser (630 nm wavelength, 300-800 mW of power, energy dose of 200-300 J/cm) after intravenous injection of 5 mg/kg of hematoporphyrin derivative. Eighteen patients (29.5%) had in situ carcinoma (Tis), 30 (48.5%) had T1-stage cancer, 7 (11%) had T2-stage cancer, and 7 (11%) had recurrent disease in the anastomotic area after previous surgery without evidence of invasion outside the lumen. Patients with residual disease after two rounds of PDT received definitive radiotherapy. Patients were evaluated for response to therapy and survival. The follow-up time ranged from 3 to 90 months (median, 32 months). RESULTS: The complete response (CR) rate was 37% (23 of 62) in patients who received PDT alone and 82% (51 of 62) in those who also received radiotherapy. The CR rate after PDT alone was statistically higher (p = 0.04) for patients who had Tis/T1 lesions (21 of 48; 44%) than for those with T2-stage disease (2 of 7; 28%) or recurrent tumors (0 of 7; 0%). Fifty-two percent of patients who had CR following PDT alone did not suffer local tumor recurrence. The median local progression-free survival times after PDT and additional radiotherapy (in cases with incomplete response) was 49 months for Tis- and T1-stage lesions, 30 months for those with T2-stage disease, and 14 months for patients with locally recurrent disease. Patients who completely responded to PDT had a median overall survival (OS) of 50 months, which was significantly longer (p < 0.003) than that of patients not responding to PDT. Toxicity was minimal; we recorded three cases of esophageal stenosis (7%) and one case of tracheo-esophageal fistula (2.5%) after combined PDT and radiotherapy. CONCLUSION: PDT is an effective regimen for early esophageal cancer, giving a CR rate of about 40%, long-term local control and favorable overall survival. Additional radiotherapy in cases of incomplete response to PDT is effective and potentially curative in another 45% of cases.  相似文献   
15.
The assessment of the angiogenic profile of tumors may become an important tool as a guide for the inclusion of novel drugs and molecular therapies into the standard chemoradiotherapy policy. Several studies have shown the prognostic importance of microvessel density (MVD) and of angiogenic factor expression in operable gastric cancer. In the present study we investigated, with immunohistochemistry the MVD, the expression of vascular endothelial growth factor (VEGF) and of thymidine phosphorylase (TP) expression, as well as the nuclear expression of p53 protein, in a series of patients with locally advanced inoperable gastric cancer. A strong association of VEGF with TP expression was noted (P = 0.005), and tumors coexpressing these factors had a statistically higher MVD (P = 0.0001). Nuclear p53 accumulation was also related to a high MVD (P = 0.004), and this was independent of VEGF or TP expression. Microvessel density showed a bell-shaped association with prognosis; cases with an intermediate MVD exhibit a favorable outcome (P < 0.05). A trend of nuclear TP expression to define a group of patients with poorer prognosis was noted (P = 0.06), while none of the remaining variables showed any significant association. The immunostaining results allowed the grouping of the angiogenic profile in four major categories: 1) highly vascularized tumors with VEGF and/or TP expression (about 36% of cases); 2) highly angiogenic tumors with p53 nuclear accumulation and low VEGF/TP expression (7% of cases); 3) poorly vascularized tumor with low VEGF/TP and negative nuclear p53 staining (32% of cases); 4) poorly vascularized tumors with TP expression (7% of cases). Specific therapies targeting hypoxia, VEGF, or TP expression as well as p53 gene therapy have entered clinical experimentation or are already available for clinical use. Using the suggested markers more than 80% of locally advanced gastric carcinomas can be grouped in different categories according to their angiogenic profile. Such a categorization may be useful for phase III trials on novel therapies targeting the major angiogenesis-related features studied here.  相似文献   
16.
Taxanes have been shown to interact with anti-apoptotic proteins. In the present study we investigated whether the addition of taxane in combination with DNA damaging drugs can further enhance tumor shrinkage in cases with incomplete response to radiotherapy. Since the dose of docetaxel in combination with carboplatin is not known, the above hypothesis was tested in the context of a dose escalation phase I study. Twenty-eight patients with locally advanced chest or pelvic tumors, showing residual disease on CT scans performed 40 d following docetaxel radio-chemotherapy, were recruited in a dose escalation protocol of docetaxel/carboplatin supported with amifostine and GM-CSF. The starting dose of docetaxel was 40 mg/m2 every 2 weeks. Carboplatin dose was calculated using the Calvert formula and was escalated in cohorts of 4 patients (starting dose AUC2 every two weeks; AUC0.5 increments up to AUC3). Thereafter the docetaxel dose was increased to 50 and 60 mg/m2, while carboplatin was escalated (by AUC0.5 increments) starting from AUC3 and AUC4 respectively. Amifostine (600 mg/m2) was administered i.v. before carboplatin and GM-CSF (480μg) was injected s.c. on days 5, 6 and 10, 11 of each cycle. Six cycles were given and response was assessed 2 weeks after the end of chemotherapy. None out of four patients treated in the 6th dose level cohort (50mg/m2 of docetaxel and AUC4 of carboplatin every 2 weeks) showed any grade 2–4 hematologic toxicity. Mild non-hematologic toxicity such as neuropathy, leg edema, pleural effusion, pyrexia, alopecia grade 2 and hypersensitivity was observed in 4–12% of patients. Out of four patients treated in a 7th cohort (docetaxel 60mg/m2 and carboplatin AUC4), one developed grade IV neutropenia and two developed grade 3 severe asthenia requiring treatment delay for 2 weeks. Out of 11 patients with PR following docetaxel radio-chemotherapy, 7 (63%) showed CR after docetaxel/carboplatin additional chemotherapy. Eight out of 17 patients with MR following docetaxel radio-chemotherapy showed PR (47%) and one showed CR (6%) after additional chemotherapy. High dose combined docetaxel (50 mg/m2) and carboplatin (AUC4) chemotherapy can be safely administered on a two-weekly basis if supported with amifostine and GM-CSF. Such an additional therapy may be important in patients with incomplete response after chemo-RT. Broad spectrum cytoprotection with amifostine and GM-CSF may also contribute to the reduction of incidence of neurosensory reactions and asthenia in patients treated with taxanes.  相似文献   
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The assessment of tumor molecular features in combination with the detection of occult malignant cells may provide important clinical information, beyond the standard staging of breast cancer. Using a nested RT-PCR technique, we assessed prospectively the presence of cytokeratin-19 (CK19) mRNA positive cells in the blood of 100 operated patients with breast cancer before the initiation of adjuvant chemotherapy and local radiotherapy. Tissue samples were prospectively collected and analyzed for estrogen (ER) and progesterone (PgR) receptor, c-erbB-2 overexpression, mutant-p53 and bcl-2 protein accumulation, proliferation index and microvessel density (MVD). CK-19 mRNA-positive cells were detected in the peripheral blood of 33% of patients. Simultaneous display of high intratumoral MVD and of CK-19 mRNA-positive cells, which characterized highly angiogenic and disseminated in the peripheral blood (HAD) disease was noted in 25% of patients. Detection of CK-19 positive cells was significantly associated with increased MVD (p = 0.002). In univariate analysis (median follow-up 30 months) CK19 mRNA detection and MVD were the most significant factors related to a short relapse-free survival (RFS), (p < 0.0001). In multivariate analysis, CK19 positivity, high MVD and c-erbB-2 overexpression were the only significant and independent variables associated with relapse (p = 0.0005, 0.03 and 0.04, respectively). Patients with HAD had an expected relapse rate close to 70% vs. <5% in the remaining patients irrespectively of the used chemotherapy regimen. The simultaneous presence of high MVD and CK19-positive cells in the blood of patients with early breast is linked with poor prognosis, which cannot be improved with standard chemotherapy regimens.  相似文献   
20.
Although angiogenetic therapy using recombinant growth factors holds much hope for the treatment of ischemic diseases, there are still unanswered questions including the method, doses or duration of therapeutic approach. We evaluated the angiogenetic effects of vascular endothelial growth factor (VEGF) on rat heart and gastrocnemius muscles when this was administered intramuscularly and compared them to those obtained from rats, which exercised daily. CONCLUSION: Both daily swimming exercise and intramuscular administration of VEGF increased angiogenesis in rat heart, even though exercise alone was the only one that increased angiogenesis quite significantly. The combined protocol (administration of growth factor and exercise) led to an increase of angiogenesis in cardiac muscles. In contrast, there was no effect on the lateral gastrocnemius muscle either by VEGF or exercise, whereas these together induced angiogenesis locally at the site of injection.  相似文献   
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