A two-cohort phase II clinical trial of gemcitabine plus treosulfan in patients with metastatic uveal melanoma.

In-vitro synergy of treosulfan and gemcitabine has been observed in chemotherapy-resistant tumours. This trial investigated the efficacy of gemcitabine plus treosulfan in metastatic uveal melanoma. Patients received 1000 mg/m of gemcitabine and treosulfan at a dose of 2500 or 3000 mg/m2 in cohort 1 and 3500 or 4000 mg/m2 in cohort 2. Chemotherapy was administered on days 1 and 8 every 4 weeks. Thirty-three patients were treated, 14 in cohort 1 and 19 in cohort 2. In cohort 1 with a treosulfan dose of or=3500 mg/m2 in cohort 2, one had partial remission (5%), 10 showed disease stabilization and eight progressed. An increased survival was observed in the second cohort with higher treosulfan doses, with median survival times of 6.0 versus 9.0 months (P=0.03) in cohort 1 and 2, respectively, and a 1-year survival of 7.1% versus 47.3%, respectively. Based on the observation of prolonged disease stabilization, we recommend further investigation of the gemcitabine/treosulfan combination with a dose of 3500 mg/m2 of treosulfan in metastatic uveal melanoma.

Wilms tumor gene (WT1) expression as a panleukemic marker.

The Wilms tumor gene (WT1) is expressed in blasts of patients with acute leukemia, irrespective of lineage, and WT1 nuclear protein is detectable in the majority of such blasts. Only very few physiologic hematopoietic progenitors express WT1, but the WT1 expression level of these progenitors and that of leukemic blasts are comparable. Although not specific for acute hematologic malignant diseases, continuous WT1 expression in almost all leukemic blasts strikingly contrasts to its rather transient expression in very few physiologic hematopoietic progenitors. Quantitative and semiquantitative WT1 reverse transcriptase polymerase chain reaction (RT-PCR) protocols have limitations in discriminating physiologic from pathologic overall WT1 expression levels in mononuclear cell preparations. Because of these limitations, reports conflict on the usefulness of long-term monitoring of WT1 expression in patients with acute leukemia. Real-time quantitative WT1 RT-PCR protocols, however, have been developed and tested in small series of patients with acute leukemia. Such protocols hold promise to enable evaluation of the individual treatment response (short-term monitoring) and early diagnosis of imminent relapse through the detection and long-term monitoring of minimal residual disease in patients with acute leukemia. These protocols also should facilitate the notoriously difficult distinction between eosinophilic leukemia and hypereosinophilic syndromes. Data on WT1 expression in leukemic blasts and their physiologic counterparts are discussed in light of clinical relevance.

Ifosfamide/liposomal daunorubicin is a well tolerated and active first-line chemotherapy regimen in advanced soft tissue sarcoma: results of a phase II study.

BACKGROUND: The anthracycline/ifosfamide combination is the most effective chemotherapy in soft tissue sarcoma. To improve the tolerability and potential efficacy of this combination, the authors combined a moderate dose of continuous infusion ifosfamide with liposomal daunorubicin (L-Dauno). METHODS: In a single-arm, Phase II study, 40 patients with a median age of 57 years (range, 19-78 years) were enrolled. Of these, 35 patients were treated with first-line chemotherapy. The treatment regimen was comprised of ifosfamide at a dose of 5 g/m(2) over 24 hours and L-Dauno at a dose of 100 mg/m(2) every 4 weeks with granulocyte-colony-stimulating factor support. RESULTS: Eleven (31%) of 35 anthracycline/ifosfamide-naive patients achieved a partial/complete response, 6 patients (17%) had stable disease, and 13 patients (37%) had disease progression. Three patients were not evaluable, and there were two intermittent deaths. The median time to disease progression was 6 months, the median overall survival was 14 months, and the median time to treatment failure was 15 months. Toxicity was tolerable. CONCLUSIONS: The combination of Ifosfamide and L-Dauno was found to be a highly active chemotherapy regimen for first-line treatment of soft tissue sarcoma. Therefore, we believe randomized studies with this regimen are warranted.

Expression of Wilms' tumor gene 1 at different stages of acute myeloid leukemia and analysis of its major splice variants.

WT1 is a transcription factor involved in differentiation and proliferation of acute myeloid leukemia (AML) blasts and is expressed in 90% of cases, as determined by nested reverse transcription polymerase chain reaction (RT-PCR). It is proposed to be a key molecule in leukemia promotion. To assess the relevance of WT1 expression, we analyzed blood and bone marrow samples from 58 AML patients (37 at diagnosis, 8 in hematological remission, and 13 at relapse) for the level of WT1 expression, using quantitative real-time RT-PCR. In addition, 21 randomly chosen samples were also analyzed for the quantitative expression of the main WT1 splice variants. As expected, samples from patients at the time of diagnosis or relapse showed significantly higher WT1 expression compared to samples from patients in remission or control samples. No striking difference in expression levels was found between various French-American-British (FAB) subtypes. The level of WT1 expression observed in patients at the time of initial diagnosis was similarly high in patients at relapse. Expression of the four main isoforms (E5+/KTS+, E5-/KTS+, E5+/KTS-, and E5-/KTS-) was found in all samples with significantly higher expression levels of the E5+ variants. Together, these findings support the potential of WT1 as a target for novel treatment approaches in AML.

Possible regulation of Wilms' tumour gene 1 (WT1) expression by the paired box genes PAX2 and PAX8 and by the haematopoietic transcription factor GATA-1 in human acute myeloid leukaemias.

Overexpression of the embryonic transcription factor, Wilms' tumour protein 1 (WT1), is common in acute myeloid leukaemias (AML). Mutations of Wilms' tumour gene 1 (WT1) in AML are rare and WT1 expression may be increased by other transcription factors. PAX2, PAX8 and GATA-1 are known physiological regulators of WT1. In the present study, we analysed either bone marrow or blood samples of 43 AML patients for the expression levels of WT1, PAX2, PAX8 and GATA-1 by real-time reverse transcription polymerase chain reaction (LightCycler). Bone marrow samples of patients without haematological malignancies and stem cell preparation samples from healthy donors and lymphoma patients served as controls. PAX2 expression was found in 11 of 43 AML samples, with a clear correlation of PAX2 with WT1 expression levels observed. PAX8 expression was found in two additional samples. GATA-1 expression was detectable in 41 of 43 AML samples and also in all control samples; no significant differences between these groups were observed and no correlation of GATA-1 expression with WT1 expression levels was apparent. In conclusion, PAX2, and possibly PAX8, appears to be a candidate for the upregulation of WT1 in a proportion of AML, whereas GATA-1 expression cannot be explained as an inducer of WT1. In two-thirds of leukaemias from our series, the basis of WT1 upregulation cannot be explained by the simple upregulation of the known WT1 activators.