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71.
Silverman Jerald; Katayama Shoichi; Zelenakes Kenneth; Lauber Joan; Musser Theresa K.; Reddy Madhusudhan; Levenstein Marcia J.; Weisburger John H. 《Carcinogenesis》1981,2(11):1167-1172
The possible modifying effect of synthetic and natural retinoidson the incidence of colon cancer in rats induced by 2 intrarectaldoses of 2.5 mg of N-methyl-N-nitrosourea (MNU) given once aweek for 2 successive weeks or a single 150 mg/kg body weightdose of 1,2-dime-thylhydrazine (DMH), s.c. was investigated.Emphasis was on the effect of the development of early tumorsas visualized by endoscopy. With the retinoids N-ethyl-retinamide,N-2-hydroxyethylretinamide, N-(4-hydro- xyphenyl)-all-trans-retinamide(RAHA), and retinyl acetate (RA) administered orally after thecarcinogens, significant differences in early developing tumorswere not found. At histopathological examination of the tumorsthe RAHA + DMH group had significantly fewer adenomas per animal.The percentage of adenoma bearing rats was significantly lowerin groups receiving RAHA + DMH or RA + DMH. However, food consumptionwas lower in rats consuming either RAHA or RA. Retinyl palmitate(RP) and RAHA was administered intrarectally to MNU-inducedrats either before or after the carcinogen. When administeredbefore MNU, RP caused a significant increase in the percentageof tumor bearing animals and the average number of tumors peranimal as visualized endos copically. At histopathological examination,all retinoid groups except RAHA given after the carcinogen,produced significantly more adenomas per animal and a significantlygreater adenoma incidence than did the control groups. Thus,in two systems, the oral administration of retinoids did notclearly inhibit the early or later stages of colon tumor development.Inirarectal infusion of two retinoids had no effect on colonicmor phology but at histopathological examination of later stagetumors there was an enhanced adenoma response. 相似文献
72.
PURPOSE: Monoclonal antibody-mediated targeting of liposomal anticancer drugs to surface antigens expressed on malignant B cells can be an effective strategy for treating B-cell malignancies. In a murine model of human B-cell lymphoma, we have made in vitro and in vivo comparisons of long-circulating sterically stabilized (Stealth) immunoliposome (SIL) formulations of two anticancer drugs, vincristine (VCR) and doxorubicin (DXR), with different mechanisms of action and drug release rates. EXPERIMENTAL DESIGN: SIL formulations of VCR or DXR were conjugated to the monoclonal antibody anti-CD19 (SIL[alphaCD19]) or its Fab' fragments (SIL[Fab']). Specific binding of SILs to Namalwa cells was studied using radiolabeled liposomes, and cytotoxicities of DXR- or VCR-loaded SILs were quantitated by a tetrazolium assay. Pharmacokinetic and drug leakage experiments were performed in mice using dual-labeled liposomes, and the therapeutic responses of SILs were evaluated in a Namalwa (human B lymphoma) cell xenograft model. RESULTS: SIL[alphaCD19] or SIL[Fab'] had higher association with and cytotoxicity against Namalwa cells than nontargeted liposomes. SIL[Fab'] had longer circulation times than SIL[alphaCD19], and VCR had faster release rates from the liposomes than DXR. SIL formulations of either VCR or DXR had significantly better therapeutic outcomes than nontargeted liposomes or free drugs. SILs loaded with VCR were superior to those loaded with DXR. SIL[Fab'] had better therapeutic outcomes than SIL[alphaCD19] for the drug DXR but were equally efficacious for the drug VCR. CONCLUSIONS: Treatment of a B lymphoma model with single injections of anti-CD19-targeted liposomal formulations of VCR resulted in high levels of response and long-term survivors. Responses to anti-CD19-targeted liposomal DXR were more modest, although the longer circulation times of SIL[Fab'] versus SIL[alphaCD19] led to superior therapeutics for DXR-loaded immunoliposomes. 相似文献
73.
Randomized, placebo-controlled study of oregovomab for consolidation of clinical remission in patients with advanced ovarian cancer. 总被引:8,自引:0,他引:8
Jonathan S Berek Peyton T Taylor Alan Gordon Mary J Cunningham Neil Finkler James Orr Saul Rivkin Birgit C Schultes Theresa L Whiteside Christopher F Nicodemus 《Journal of clinical oncology》2004,22(17):3507-3516
PURPOSE: To assess oregovomab as consolidation treatment of advanced ovarian cancer and refine the immunotherapeutic strategy for subsequent study. PATIENTS AND METHODS: Patients with stage III/IV ovarian cancer who had a complete clinical response to primary treatment were randomly assigned to oregovomab or placebo administered at weeks 0, 4, and 8, and every 12 weeks up to 2 years or until recurrence. The primary end-point was time to relapse (TTR). RESULTS: One hundred forty-five patients were treated with oregovomab (n = 73) or placebo (n = 72). For the population overall, median TTR was not different between treatments at 13.3 months for oregovomab and 10.3 months for placebo (P =.71). Immune responses were induced in most actively treated patients. This was associated with prolonged TTR. Quality of life was not adversely impacted by treatment. Adverse events were reported with similar frequency in oregovomab and placebo groups, indicating a benign safety profile. A long-term survival follow-up is ongoing. Cox analysis of relapse data identified significant factors: performance status, CA-125 before third cycle, and baseline CA-125. Further evaluation identified a subpopulation with favorable prognostic indicators designated as the successful front-line therapy (SFLT) population. For the SFLT population, TTR was 24.0 months in the oregovomab group compared with 10.8 months for placebo (unadjusted hazard ratio of 0.543 [95% CI, 0.287 to 1.025]), a hypothesis-generating observation. CONCLUSION: Consolidation therapy with oregovomab did not significantly improve TTR overall. A set of confirmatory phase III studies has been initiated to determine whether the SFLT population derives benefit from oregovomab treatment. 相似文献
74.
Tight junction proteins claudin-3 and claudin-4 are frequently overexpressed in ovarian cancer but not in ovarian cystadenomas. 总被引:18,自引:0,他引:18
75.
Targeted liposomal c-myc antisense oligodeoxynucleotides induce apoptosis and inhibit tumor growth and metastases in human melanoma models. 总被引:7,自引:0,他引:7
Fabio Pastorino Chiara Brignole Danilo Marimpietri Gabriella Pagnan Adriana Morando Domenico Ribatti Sean C Semple Claudio Gambini Theresa M Allen Mirco Ponzoni 《Clinical cancer research》2003,9(12):4595-4605
PURPOSE: Melanoma is a highly malignant and increasingly common tumor. Because the cure rate of metastatic melanoma by conventional treatment is very low, new therapeutic approaches are needed. We previously reported that coated cationic liposomes (CCL) targeted with a monoclonal antibody against the disialoganglioside (GD(2)) and containing c-myb antisense oligodeoxynucleotides (asODNs) resulted in a selective inhibition of the proliferation of GD(2)-positive neuroblastoma cells in vitro. EXPERIMENTAL DESIGN: Here, we tested the in vivo antitumor effects of this novel antisense liposomal formulation by targeting the c-myc oncogene on melanoma, a neuroectodermal tumor sharing with neuroblastoma the expression of GD(2). RESULTS: Our methods produced GD(2)-targeted liposomes that stably entrapped 90% of added c-myc asODNs. These liposomes showed a selective binding for GD(2)-positive melanoma cells in vitro. Melanoma cell proliferation was inhibited to a greater extent by GD(2)-targeted liposomes containing c-myc asODNs (aGD(2)-CCL-myc-as) than by nontargeted liposomes or free asODNs. The pharmacokinetic results obtained after i.v. injection of [(3)H]-myc-asODNs, free or encapsulated in nontargeted CCLs or GD(2)-targeted CCLs, showed that free c-myc-asODNs were rapidly cleared, with less than 10% of the injected dose remaining in blood at 30 min after injection. c-myc-asODNs encapsulated within either CCL or aGD(2)-CCL demonstrated a more favorable profile in blood, with about 20% of the injected dose of each preparation remaining in vivo at 24 h after injection. In an in vivo melanoma experimental metastatic model, aGD(2)-CCL-myc-as, at a total dose of only 10 mg of asODN per kilogram, significantly inhibited the development of microscopic metastases in the lung compared with animals treated with myc-asODNs, free or entrapped in nontargeted liposomes, or aGD(2)-CCL encapsulating scrambled asODNs (P < 0.01). Moreover, mice bearing established s.c. human melanoma xenografts treated with aGD(2)-CCL-myc-as exhibited significantly reduced tumor growth and increased survival (P < 0.01 versus control mice). The mechanism for the antitumor effects appears to be down-regulation of the expression of the c-myc protein and interruption of c-myc-mediated signaling: induction of p53 and inhibition of Bcl-2 proteins, leading to extensive tumor cell apoptosis. CONCLUSION: These results suggest that inhibition of c-myc proto-oncogene by GD(2)-targeted antisense therapy could provide an effective approach for the treatment of melanoma in an adjuvant setting. 相似文献
76.
Cost containment has captured the attention of health policymakers in most OECD countries, and deliberations about creating powerful financial incentives dominate health care politics. Some European health systems are now implementing hospital payment schemes that mirror the U.S. model of diagnosis-related groups (DRGs) and are raising premiums and copayment levels in an effort to limit public expenditures. Though financial incentives may indeed help rein in health expenditures, focusing predominantly on financial incentives hinders due consideration of needed structural reforms that improve the continuity, quality, and appropriateness of health care service delivery. This article focuses on the structural specifics of two legally enacted health insurance systems (Germany and Austria) and two national health systems (Great Britain and Denmark) to discuss the influence of structural characteristics on cost-containment efforts. Structural reform strategies discussed include increasing reliance on general practitioners, improving coordination of community and hospital-based specialty care, addressing the stark divide between ambulatory and hospital-based care that exists in some European health systems, and improving continuity of care by better integrating medical and social care sectors. Also discussed is the relative focus on financial incentives versus structural deficits in recent European-health care reform strategies. 相似文献
77.
Samuel R. Friedman Barbara Tempalski Hannah Cooper Theresa Perlis Marie Keem Risa Friedman Peter L. Flom 《Journal of urban health》2004,81(3):377-400
This article estimates the population prevalence of current injection drug users (IDUs) in 96 large US metropolitan areas
to facilitate structural analyses of its predictors and sequelae and assesses the extent to which drug abuse treatment and
human immunodeficiency virus (HIV) counseling and testing are made available to drug injectors in each metropolitan area.
We estimated the total number of current IDUs in the United States and then allocated the large metropolitan area total among
large metropolitan areas using four different multiplier methods. Mean values were used as best estimates, and their validity
and limitations were assessed. Prevalence of drug injectors per 10,000 population varied from 19 to 173 (median 60; interquartile
range 42–87). Proportions of drug injectors in treatment varied from 1.0% to 39.3% (median 8.6%); and the ratio of HIV counseling
and testing events to the estimated number of IDUs varied from 0.013 to 0.285 (median 0.082). Despite limitations in the accuracy
of these estimates, they can be used for structural analyses of the correlates and predictors of the population density of
drug injectors in metropolitan areas and for assessing the extent of service delivery to drug injectors. Although service
provision levels varied considerably, few if any metropolitan areas seemed to be providing adequate levels of services. 相似文献
78.
Noninvasive monitoring of murine tumor blood flow during and after photodynamic therapy provides early assessment of therapeutic efficacy. 总被引:1,自引:0,他引:1
Guoqiang Yu Turgut Durduran Chao Zhou Hsing-Wen Wang Mary E Putt H Mark Saunders Chandra M Sehgal Eli Glatstein Arjun G Yodh Theresa M Busch 《Clinical cancer research》2005,11(9):3543-3552
PURPOSE: To monitor tumor blood flow noninvasively during photodynamic therapy (PDT) and to correlate flow responses with therapeutic efficacy. EXPERIMENTAL DESIGN: Diffuse correlation spectroscopy (DCS) was used to measure blood flow continuously in radiation-induced fibrosarcoma murine tumors during Photofrin (5 mg/kg)/PDT (75 mW/cm2, 135 J/cm2). Relative blood flow (rBF; i.e., normalized to preillumination values) was compared with tumor perfusion as determined by power Doppler ultrasound and was correlated with treatment durability, defined as the time of tumor growth to a volume of 400 mm3. Broadband diffuse reflectance spectroscopy concurrently quantified tumor hemoglobin oxygen saturation (SO2). RESULTS: DCS and power Doppler ultrasound measured similar flow decreases in animals treated with identical protocols. DCS measurement of rBF during PDT revealed a series of PDT-induced peaks and declines dominated by an initial steep increase (average +/- SE: 168.1 +/- 39.5%) and subsequent decrease (59.2 +/- 29.1%). The duration (interval time; range, 2.2-15.6 minutes) and slope (flow reduction rate; range, 4.4 -45.8% minute(-1)) of the decrease correlated significantly (P = 0.0001 and 0.0002, r2= 0.79 and 0.67, respectively) with treatment durability. A positive, significant (P = 0.016, r2= 0.50) association between interval time and time-to-400 mm3 was also detected in animals with depressed pre-PDT blood flow due to hydralazine administration. At 3 hours after PDT, rBF and SO2 were predictive (P < or = 0.015) of treatment durability. CONCLUSION: These data suggest a role for DCS in real-time monitoring of PDT vascular response as an indicator of treatment efficacy. 相似文献
79.
Theresa H M Keegan Sally L Glaser Christina A Clarke Margaret L Gulley Fiona E Craig Joseph A Digiuseppe Ronald F Dorfman Risa B Mann Richard F Ambinder 《Journal of clinical oncology》2005,23(30):7604-7613
PURPOSE: Epstein-Barr virus (EBV) in Hodgkin's lymphoma (HL) cells has been considered as a prognostic marker for this heterogeneous disease, but studies have yielded mixed findings, likely because of selected patient series and failure to acknowledge an effect of age on outcome. This study assessed survival after HL in a population-based cohort large enough to examine the joint effects of EBV with other factors including age, sex, and histologic subtype. PATIENTS AND METHODS: Included were 922 patients with classical HL diagnosed between mid-1988 and 1997 in the Greater San Francisco Bay Area, with archived biopsy specimens assayed for EBV with immunohistochemistry and in situ hybridization. Vital status was followed through December 30, 2003 (median follow-up time, 97 months). Overall and disease-specific survival were analyzed with the Kaplan-Meier method and Cox proportional hazards regression models. RESULTS: In children less than 15 years old, EBV presence was suggestively associated (P = .07) with favorable survival. In adults aged 15 to 44 years, EBV did not affect HL outcome, although a protective effect was suggested. In older adults (45 to 96 years), EBV presence nearly doubled the risk of overall and HL-specific mortality but only for patients with nodular sclerosis (NS) histologic subtype (hazard ratio for death = 2.5; 95% CI, 1.5 to 4.3). CONCLUSION: In HL, EBV tumor cell presence is associated with better survival in young patients and poorer survival in older patients with NS, independent of other factors. Variation in outcome by age and histology could indicate biologically distinct disease entities. Evidence that EBV is a meaningful prognostic marker may have therapeutic relevance. 相似文献
80.