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991.
In vitro and in vivo antitumor properties of the cyclin dependent kinase inhibitor CYC202 (R-roscovitine) 总被引:4,自引:0,他引:4
McClue SJ Blake D Clarke R Cowan A Cummings L Fischer PM MacKenzie M Melville J Stewart K Wang S Zhelev N Zheleva D Lane DP 《International journal of cancer. Journal international du cancer》2002,102(5):463-468
CDK2 inhibitors have been proposed as effective anti-cancer therapeutics. We show here that CYC202 (R-roscovitine) is a potent inhibitor of recombinant CDK2/cyclin E kinase activity (IC(50) = 0.10 microM) with an average cytotoxic IC(50) of 15.2 microM in a panel of 19 human tumour cell lines, and we also demonstrate selectivity for rapidly proliferating cells over non-proliferating cells. A study of the cell cycle effects of CYC202 in Lovo colorectal carcinoma cells showed that the major effect was not the predicted arrest in one part of the cycle, but rather an induction of cell death from all compartments of the cell cycle. The maximum tolerated dose given intravenously to mice was in excess of 20 mg/kg. Doses up to 2,000 mg/kg were tolerated when administered orally in mice. Following repeated intraperitoneal administration (3 times daily for 5 days) of 100 mg/kg to nude mice bearing the Lovo human colorectal tumour, CYC202 induced a significant antitumour effect with a 45% reduction in tumour growth compared to controls. A second experiment using the human uterine xenograft MESSA-DX5 treated with orally administered CYC202 (500 mg/kg 3 times daily for 4 days) also exhibited a significant reduction in the rate of growth of the tumour (62%). These data, showing enzyme and cellular potency together with antitumour activity, confirm the potential of CDK2 inhibitors such as CYC202 as anticancer drugs. 相似文献
992.
Stewart AJ Southcott BM 《Clinical oncology (Royal College of Radiologists (Great Britain))》2002,14(6):494-496
This report describes an interesting case of severe diarrhoea following high-dose chemotherapy for non-Hodgkin's lymphoma. This caused significant morbidity and resolved on a gluten-free diet. Copyright 2002 The Royal College of Radiologists. Published by Elsevier Science Ltd. All rights reserved. 相似文献
993.
ALK-positive anaplastic large T-cell lymphoma preceded by Epstein-Barr virus infection complicated by development of an aorto-esophageal fistula 总被引:1,自引:0,他引:1
We report an unusual case of aggressive ALK-positive anaplastic large cell lymphoma with widespread mediastinal involvement immediately preceded by an acute Epstein-Barr virus (EBV) infection. Following initiation of chemotherapy and radiological evidence of significant tumor regression, the patient suffered a fatal massive upper gastrointestinal hemorrhage from an aorto-esophageal fistula. The relevant literature relating to EBV in the pathogenesis of ALK-lymphomas and literature relating to aorto-enteric fistula (AEF) in mediastinal lymphoma is reviewed. 相似文献
994.
Kolden GG Strauman TJ Ward A Kuta J Woods TE Schneider KL Heerey E Sanborn L Burt C Millbrandt L Kalin NH Stewart JA Mullen B 《Psycho-oncology》2002,11(5):447-456
Evidence is accumulating for physical activity as an effective, well-tolerated, highly rewarding complementary behavioral intervention for enhancing quality of life (QOL) as well as fitness among individuals with chronic and even terminal illnesses. However, relatively few studies have examined the feasibility and potential health benefits of supervised, structured exercise programs for sedentary women with primary breast cancer. Forty women over the age of 45 with primary breast cancer participated in a course of group exercise training (GET) delivered in a structured format three times per week for 16 weeks. GET emphasizes physical activities that promote aerobic fitness, strength, and flexibility. Assessments of fitness/vigor and QOL were conducted prior to, during, and upon completion of the program. Results demonstrated that GET was feasible, safe, and well-tolerated. Moreover, the participants experienced significant health benefits over the course of the intervention in multiple dimensions of fitness/vigor (aerobic capacity, strength, flexibility) as well as QOL (increased positive affect, decreased distress, enhanced well-being, and improved functioning). Discussion highlights the need for inclusion of physical activity programs in comprehensive, complementary treatment regimes for breast cancer patients. 相似文献
995.
Williams MB More MJ Narayanan D Majewski S Weisenberger AG Wojcik R Stanton M Phillips W Stewart A 《Technology in cancer research & treatment》2002,1(1):39-42
Scintimammography, or single gamma nuclear imaging of the breast, has shown promise as a way of characterizing certain biological properties of suspicious breast masses. Conventional scintimammography, performed using large clinical gamma cameras and prone patient positioning suffers from several drawbacks including poor sensitivity for small (> 1 cm) lesions and no reliable method for correlating scintigraphic findings with those of other imaging modalities. We are developing a system designed to overcome some of these problems. The system combines x-ray mammography with scintimammography on a common gantry. The x-ray and gamma ray images are obtained in quick succession, with the breast in a common configuration under mild compression. A digital x-ray detector is used, permitting rapid assessment of lesion location prior to gamma imaging, and enabling fusion of the x-ray transmission and gamma emission information in a single digital image. In a pilot clinical diagnostic study, the system has demonstrated high pathology-proven accuracy in differentiating benign and malignant masses. 相似文献
996.
BACKGROUND: The T1 and T2 classifications of the International Union Against Cancer TNM classification system for renal cell carcinoma are based on primary tumor size, and in various editions of the classification, the cut points between T1 and T2 have been amended to provide clinical utility. In the current edition, the T1/T2 cut point is less than or equal to and greater than 7 cm. and more recently a subdivision of the T1 classification (less than or equal to and < 4 cm) has been proposed to identify patients suitable for partial nephrectomy. This study investigates the prognostic significance of tumor size in a series of organ-confined clear cell renal cell carcinomas. METHODS: One hundred thirty cases of organ-confined clear cell renal cell carcinomas, with a minimum of 5 years' follow-up, were identified from the New South Wales Cancer Registry. Tumor size was compared with survival using the method of Kaplan and Meier for TNM size categories, and proportional hazards regression was used for assessing size as a continuous variable. Proportional hazards regression also was used for multivariable comparisons of size and other prognostic parameters (Fuhrman grade, AgNOR score, and Ki-67 index) against survival. RESULTS: Of 116 cases for which tumor dimension was recorded, 25 patients had died of cancer-related causes. Primary tumor size ranged from 12 to 140 mm (mean, 57.3 mm). The association between survival and size was significant irrespective of the TNM classification and was also significant when size was modeled continuously (P = 0.000125, hazard of death increased by 3.51 times for each doubling of tumor size). On univariate analysis, Fuhrman grade (P = 0.04) and AgNOR score (P = 0.015) were associated with survival; however, on multivariate analysis only tumor size retained significance. CONCLUSIONS: Although the cut point of T1 and T2 TNM categories and the proposed T1 subdivision cut point correlate with survival, our finding that size is a continuous variable indicates that as a prognostic parameter for clear cell renal cell carcinoma, primary tumor size is relative rather than indicative. 相似文献
997.
Wotton S Stewart M Blyth K Vaillant F Kilbey A Neil JC Cameron ER 《Cancer research》2002,62(24):7181-7185
The RUNX1/AML1 gene is a frequent target for chromosomal translocations in human leukemia. The biological properties of the resulting fusion products and the finding that haploinsufficiency increases the risk of developing leukemia (W-J. Song et al., Nat. Genet., 23: 166-175, 1999; M. Osata et al., Blood, 93: 1817-1824, 1999) have led to the widely held view that RUNX1 loss-of-function is a key event. However, we now report that the gene is a target for insertional mutagenesis in T-cell lymphomas of mice carrying a MYC oncogene, where promoter insertion results in overexpression without affecting the integrity of the coding sequence. Moreover, Runx1 haploinsufficiency does not accelerate lymphoma development in MYC/Runx2 transgenic or murine leukemia virus-infected mice. These findings reveal that the Runx1 gene can also act as a dominant oncogene and suggest that the involvement of the Runx gene family in human leukemia may be more widespread and complex than previously realized. 相似文献
998.
Lee AW Kwong DL Leung SF Tung SY Sze WM Sham JS Teo PM Leung TW Wu PM Chappell R Peters LJ Fowler JF 《International journal of radiation oncology, biology, physics》2002,53(1):75-85
PURPOSE: To study the factors affecting the risk of symptomatic temporal lobe necrosis after different fractionation schedules. METHODS AND MATERIALS: One thousand thirty-two patients with T1-2 nasopharyngeal carcinoma treated with radical radiotherapy in Hong Kong during 1990-1995 were studied. They were treated at four different centers with similar techniques but different fractionation schedules: 984 patients were given 1 fraction daily throughout (q.d.), and 48 patients were irradiated twice daily (b.i.d.) for part of the course. The median total dose was 62.5 Gy (range 50.4-71.2), dose per fraction was 2.5 Gy (range 1.6-4.2), and overall treatment time (OTT) was 44 days (range 29-70). In addition, 500 patients received supplementary doses for parapharyngeal extension, 113 received booster doses by brachytherapy, and 114 received sequential chemotherapy using cisplatin-based regimes. RESULTS: Altogether, 24 patients developed symptomatic temporal lobe necrosis: 18 from the q.d. group and 6 from the b.i.d. group. The 5-year actuarial incidence ranged from 0% (after 66 Gy in 33 fractions within 44 days) to 14% (after 71.2 Gy in 40 fractions within 35 days). Multivariate analyses showed that the risk was significantly affected by the fractional effect of the product of total dose and dose per fraction (hazard ratio [HR] = 1.04, 95% confidence interval [CI] 1.02-1.05), OTT (HR 0.88, 95% CI 0.80-0.97), and b.i.d. scheduling (HR 13, 95% CI 3-54). Repeating the analyses for patients treated with the q.d. schedules confirmed the independent significance of OTT in addition to the product of total dose and dose per fraction. CONCLUSION: The tentative results suggest that in addition to fractional dose, the OTT also had significant impact on the risk of temporal lobe necrosis, and b.i.d. scheduling increased the hazard further. 相似文献
999.
Stewart KD Martinez AA Weiner S Podratz K Stromberg JS Schray M Mitchell C Sherman A Chen P Brabbins DA 《International journal of radiation oncology, biology, physics》2002,54(2):527-535
PURPOSE: To evaluate the long-term results of treatment using adjuvant whole abdominal irradiation (WAPI) with a pelvic/vaginal boost in patients with Stage I-III endometrial carcinoma at high risk of intra-abdominopelvic recurrence, including clear cell (CC) and serous-papillary (SP) histologic features. METHODS AND MATERIALS: In a prospective nonrandomized trial, 119 patients were treated with adjuvant WAPI between November 1981 and April 2000. All patients were analyzed, including those who did not complete therapy. The mean age at diagnosis was 66 years (range 39-88). Thirty-eight patients (32%) had 1989 FIGO Stage I-II disease and 81 (68%) had Stage III. The pathologic features included the following: 64 (54%) with deep myometrial invasion, 48 (40%) with positive peritoneal cytologic findings, 69 (58%) with high-grade lesions, 21 (18%) with positive pelvic/para-aortic lymph nodes, and 44 (37%) with SP or CC histologic findings. RESULTS: The mean follow-up was 5.8 years (range 0.2-14.7). For the entire group, the 5- and 10-year cause-specific survival (CSS) rate was 75% and 69% and the disease-free survival (DFS) rate was 58% and 48%, respectively. When stratified by histologic features, the 5- and 10-year CSS rate for adenocarcinoma was 76% and 71%, and for serous papillary/CC subtypes, it was 74% and 63%, respectively (p = 0.917). The 5- and 10-year DFS rate for adenocarcinoma was 60% and 50% and was 54% and 37% serous papillary/CC subtypes, respectively (p = 0.498). For surgical Stage I-II, the 5-year CSS rate was 82% for adenocarcinoma and 87% for SP/CC features (p = 0.480). For Stage III, it was 75% and 57%, respectively (p = 0.129). Thirty-seven patients had a relapse, with the first site of failure the abdomen/pelvis in 14 (38%), lung in 8 (22%), extraabdominal lymph nodes in 7 (19%), vagina in 6 (16%), and other in 2 (5%). When stratified by histologic variant, 32% of patients with adenocarcinoma and 30% with the SP/CC subtype developed recurrent disease. Most failures for either histologic group occurred within the abdominopelvic region. However, one-third of the adenocarcinoma recurrences were in the lung. Multivariate regression analysis (age, surgical stage, grade, myometrial invasion, histologic type, lymph node status, and peritoneal cytology) demonstrated age (p = 0.019) and surgical stage (p = 0.036) to be of prognostic significance for CSS; age (p = 0.036) was the only significant prognostic factor for DFS. Grade 1-2 gastrointestinal and hematologic acute toxicities were common. Asymptomatic bibasilar scarring on chest X-ray and mild elevation of liver enzymes were seen in almost 50% of the patients. Even though chronic toxicities were less frequent, 12% developed Grade 3-4 gastrointestinal and 2% Grade 3 renal toxicities. CONCLUSION: Adjuvant WAPI is very effective treatment with excellent 10-year results for Stage I-III endometrial carcinoma with risk factors for intra-abdominopelvic recurrence, including SP or CC histologic variants, deep myometrial invasion, high grade, nodal involvement, and positive peritoneal cytology. The low long-term complication rate with high CSS rate makes WAPI the treatment of choice for these patients with significant comorbidities. 相似文献
1000.
Dekker MC Nunn RJ Einfeld SE Tonge BJ Koot HM 《Journal of autism and developmental disorders》2002,32(6):601-610
The objective of the reported study was to reassess the factor structure of the Developmental Behaviour Checklist (DBC) in a large cross-cultural sample representing all levels of intellectual disability. Parent and teacher DBC ratings on a combined sample of 1536 Dutch and Australian children and adolescents (ages 3–22) with mild to profound intellectual disability were used. Principal components analyses produced five subscales: Disruptive/Antisocial, Self-Absorbed, Communication Disturbance, Anxiety, and Social Relating, explaining 43.7% of the total variance. Internal consistencies of these subscales ranged from .66 to .91. The revised factor structure of the DBC appears to be an improved and useful tool for assessing emotional and behavioral problems in children with intellectual disabilities. 相似文献