Fabry disease and vascular risk factors: future strategies for patient-based studies and the knockout murine model

Fabry disease is secondary to deficiency of the lysosomal enzyme α-galactosidase A, leading to altered glycosphingolipid metabolism and accumulation that is often associated with endothelial dysfunction. Current evidence suggests that there is impairment of the vascular nitric oxide pathway, with abnormalities evident in the cerebral circulation and in the dermal vasculature of patients with Fabry disease. Some of these findings have been confirmed in a mouse model of Fabry disease. The murine model, however, allows investigation of Fabry disease at a non-clinical level and a near complete investigation of biological processes within an affected tissue. This is of particular utility in allowing gene expression analysis of clinically inaccessible tissues such as the aorta.
Conclusion: Future developments in array technology for proteins and DNA single nucleotide polymorphism analysis, together with gene expression microarray analysis, may open a new chapter in our understanding of the biology of lysosomal storage disorders.     

Expression levels of TEL, AML1, and the fusion products TEL-AML1 and AML1-TEL versus drug sensitivity and clinical outcome in t(12;21)-positive pediatric acute lymphoblastic leukemia.

PURPOSE: t(12;21)(p13; q22), present in approximately 25% of pediatric precursor B-ALL, is highly sensitivity to L-asparaginase and the prognosis depends on the intensity of the treatment protocol. This study analyzes the relationship between the mRNA expression of the genes and fusion products involved in t(12;21), in vitro sensitivity to prednisolone, vincristine, and L-asparaginase, and long-term clinical outcome in t(12;21)+ acute lymphoblastic leukemia (ALL) patients. EXPERIMENTAL DESIGN: Long-term clinical outcome in 45 t(12;21)+ ALL patients was related to mRNA expression of TEL, AML1, TEL-AML1, and AML1-TEL, determined by real-time quantitative PCR, and the in vitro sensitivity to prednisolone, vincristine, and L-asparaginase, using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. RESULTS: A significant approximately 3.5-fold lower TEL expression in t(12;21)+ compared with t(12;21)- ALL samples (P = 0.006) and normal controls (P = 0.004) was found. Expression of AML1 did not differ between t(12;21)+ and t(12;21)- ALL. However, AML1 expression in the leukemic cells was 2-fold higher compared with normal controls (P = 0.02). The TEL-AML1 fusion product was expressed in all t(12;21)+ cases, whereas the reciprocal fusion product AML1-TEL was expressed in only 76%. High expression levels of TEL-AML1 [hazard ratio (HR), 1.3; 95% confidence interval (95% CI), 1.10-1.57; P = 0.003], AML1-TEL (HR, 4.9; 95% CI, 1.99-12.40; P = 0.001) and AML1 (HR, 1.1; 95% CI, 1.03-1.22; P = 0.006) were associated with a poor long-term clinical outcome within t(12;21)+ ALL. Cellular drug resistance towards prednisolone, vincristine, and L-asparaginase could not explain this predictive value. Multivariate analysis including age and WBC showed that only high AML1-TEL expression is an independent poor prognostic factor in t(12;21)+ childhood ALL. CONCLUSION: High AML1-TEL expression is an independent poor prognostic factor in t(12;21)+ childhood ALL.     

Hepatic arterial oxaliplatin infusion plus intravenous chemotherapy in colorectal cancer with inoperable hepatic metastases: a trial of the gastrointestinal group of the Federation Nationale des Centres de Lutte Contre le Cancer.

PURPOSE: Isolated hepatic metastases of colorectal cancer constitute a frequent and serious therapeutic problem that has led to the evaluation of hepatic arterial infusion (HAI) of different drugs. Oxaliplatin combined with fluorouracil (FU) and leucovorin is effective in the treatment of colorectal cancer. In this context, a phase II study was conducted to evaluate concomitant administration of oxaliplatin by HAI and intravenous (IV) FU plus leucovorin according to the LV5FU2 protocol (leucovorin 200 mg/m(2), FU 400 mg/m(2) IV bolus, FU 600 mg/m(2) 22-hour continuous infusion on days 1 and 2 every 2 weeks). PATIENTS AND METHODS: Patients had metastatic colorectal cancer that was restricted to the liver and inoperable. The patients were not to have previously received oxaliplatin. After surgical insertion of a catheter in the hepatic artery, patients were treated with oxaliplatin 100 mg/m(2) HAI combined with FU + leucovorin IV according to the LV5FU2 protocol. Treatment was continued until disease progression or toxicity. Response was evaluated every 2 months. RESULTS: Twenty-eight patients were included, and 26 patients were treated. Two hundred courses of therapy were administered, and the median number of courses received was eight courses (range, zero to 20 courses). The most frequent toxicity consisted of neutropenia. The main toxicity related to HAI was pain. The intent-to-treat objective response rate was 64% (95% CI, 44% to 81%; 18 of 28 patients). With a median follow-up of 23 months, the median overall and disease-free survival times were 27 and 27 months, respectively. CONCLUSION: The combination of oxaliplatin HAI and FU + leucovorin according to the LV5FU2 protocol is feasible and effective in patients presenting with isolated hepatic metastases of colorectal cancer.     

Effects of radiotherapy planning with a dedicated combined PET-CT-simulator of patients with non-small cell lung cancer on dose limiting normal tissues and radiation dose-escalation: a planning study.

BACKGROUND AND PURPOSE: To investigate the effect of radiotherapy planning with a dedicated combined PET-CT simulator of patients with locally advanced non-small cell lung cancer. PATIENTS AND METHODS: Twenty-one patients underwent a pre-treatment simulation on a dedicated hybrid PET-CT-simulator. For each patient, two 3D conformal treatment plans were made: one with a CT based PTV and one with a PET-CT based PTV, both to deliver 60Gy in 30 fractions. The maximum tolerable prescribed radiation dose for CT versus PET-CT PTV was calculated based on constraints for the lung, the oesophagus, and the spinal cord, and the Tumour Control Probability (TCP) was estimated. RESULTS: For the same toxicity levels of the lung, oesophagus and spinal cord, the dose could be increased from 55.2+/-2.0Gy with CT planning to 68.9+/-3.3Gy with the use of PET-CT (P=0.002), with corresponding TCP's of 6.3+/-1.5% for CT and 24.0+/-5.6% for PET-CT planning (P=0.01). CONCLUSIONS: The use of a combined dedicated PET-CT-simulator reduced radiation exposure of the oesophagus and the lung, and thus allowed significant radiation dose escalation whilst respecting all relevant normal tissue constraints.