Eckhart Weidmann

The tumor suppressor gene wt1 (Wilms' tumor gene) encodes for a zinc finger DNA-binding protein with predominantly transcription repressing properties. Because wt1 has been shown to be expressed in the vast majority of patients with acute myeloid leukemias (AML), we investigated the relevance of wt-1 mRNA expression regarding prognosis and possible prediction of relapse during follow-up. Totally bone marrow-derived blasts of 139 AML patients (129 newly diagnosed AML patients, 22 AML patients again in first relapse, and 10 AML patients analyzed primarily in first relapse) were studied for wt1 mRNA expression. Seventy-seven patients were analyzed for wt1 mRNA expression during follow-up. wt1-specific reverse transcription-polymerase chain reaction (RT-PCR) was performed and the amplification product was visually classified as not, weakly, moderately, or strongly amplified, as described previously. PCR products were quantitated by competitive PCR using a shortened homologous wt1 construct standard in representative cases. The expression of wt1 transcripts was correlated to age, French-American-British (FAB) subtype, phenotype, karyotype, and long-term survival. wt1 mRNA was detectable in 124 of 161 (77%) samples at diagnosis and in first relapse. wt1 expression was independent from age, antecedent myelodysplastic syndrome or FAB subtype, with the exception of a significant difference in M5 leukemias showing wt1 transcripts in only 40% (P = .0025). There was no correlation between the level of wt1 mRNA and response to treatment or the prognostic groups defined by the karyotype. Concerning long-term survival, patients with high levels of wt1 had a significantly worse overall survival (OS) than those with not detectable or low levels. The 3-year OS for all newly diagnosed AMLs was 13% and 38% (P = .038), respectively, and 12% and 43% (P = .014) for de novo AMLs. The difference was more distinct in patients less than 60 years of age. During follow-up, all patients achieving complete remission became wt1 negative. Reoccurrence of wt1 transcripts predicted relapse. The data indicate that high expression of wt1 mRNA is associated with a worse long-term prognosis.

OBJECTIVE: To analyse the immunological and virological effects of treatment interruptions in HIV-1-infected patients with treatment failure and multidrug-resistant virus. METHODS: Drug susceptibility was assessed using Antivirogram and genotypic analysis was based on population and clonal sequencing for 48 patients who had interrupted treatment (> or = 2 months). RESULTS: Treatment interruption resulted in viral load increases (mean 0.7 log 10 copies/ ml; P = 0.0001) and CD4 cell count decreases (mean 89 x 10(6) cells/l; P = 0.0001). A complete shift to wild-type virus at the phenotypic, genotypic and clonal level was observed in 28/45 patients. These patients differed from those that did not show a shift to wild type in baseline CD4 cell counts (192 versus 59 x 10(6) cells/l; P= 0.007) and in the relationship between baseline viral load and CD4 cell count (no correlation versus a significant negative correlation; P= 0.008). Response to re-initiation of treatment fell with increasing viral load [relative hazard (RH) 0.33; P= 0.001] and with increasing total number of drugs with reduced susceptibility (RH 0.51; P = 0.0003); it improved with the number of new drugs received (RH 2.12; P = 0.0002) and a shift to wild type (RH 5.22, P = 0.006). CONCLUSIONS: Changes in surrogate markers suggest that treatment provided benefit in spite of virological failure and resistant virus. Although patients with a shift to wildtype virus responded better in the short term to treatment re-initiation, the long-term effects are not known and the risk of immune deterioration needs to be carefully considered.