The LPL/ADAM29 expression ratio is a novel prognosis indicator in chronic lymphocytic leukemia

Although the zeta-associated protein of 70 kDa (ZAP-70) is overexpressed in patients with chronic lymphocytic leukemia (CLL) displaying unmutated IGVH genes and poor prognosis, a previous microarray study from our group identified overexpression of LPL and ADAM29 genes among unmutated and mutated CLL, respectively. To assess the prognostic value of these genes, we quantified their expression by real-time quantitative polymerase chain reaction (PCR) in a cohort of 127 patients with CLL and correlated this with clinical outcome, IGVH mutational status, and ZAP-70 protein expression. IGVH mutational status, ZAP-70, and the LPL and ADAM29 mRNA ratios (L/A ratio) were predictive of event-free survival for the whole cohort and for patients with stage A disease. in patients in stage B and C, the L/A ratio was an independent prognostic factor, whereas ZAP-70 did not predict survival. Simultaneous usage of the L/A ratio and ZAP-70 expression allowed an almost perfect (99%) assessment of the IGVH status in the 80% of patients with concordant results (L/A(+), ZAP-70(+) or L/A(-), ZAP-70(-)). LPL and ADAM29 gene expression could also be determined by a simple competitive multiplex reverse transcription PCR assay. Overall, quantification of LPL and ADAM29 gene expression is a strong prognostic indicator in CLL, providing better prognostic assessment than ZAP-70 in advanced stages of the disease.Hop La Pitie Salpetriere, Serv Hematol Biol, F-75013 Paris, FranceInst Pasteur, Unite Immunohematol & Immunopathol, F-75724 Paris, FranceUniversidade Federal de São Paulo, Disciplina Hematol & Hemoterapia, São Paulo, BrazilInst Pasteur, Dept Ecosyst & Epidemiol Malad Infect, Paris, FranceHop La Pitie Salpetriere, Serv Immunol, Paris, FranceInst Pasteur, Ctr Rech Vaccinale & Biomed, Paris, FranceUniversidade Federal de São Paulo, Disciplina Hematol & Hemoterapia, São Paulo, BrazilWeb of Scienc

Functional Domains of Fused, a Serine-Threonine Kinase Required for Signaling in Drosophila

fused (fu) is a segment-polarity gene encoding a putative serine-threonine kinase. In a wild-type context, all fu mutations display the same set of phenotypes. Nevertheless, mutations of the Suppressor of fused [Su(fu)] gene define three classes of alleles (fu0, fuI, fuII). Here, we report the molecular analysis of known fu mutations and the generation of new alleles by in vitro mutagenesis. We show that the Fused (Fu) protein functions in vivo as a kinase. The N-terminal kinase and the extreme C-terminal domains are necessary for Fu(+) activity while a central region appears to be dispensable. We observe a striking correlation between the molecular lesions of fu mutations and the phenotype displayed in their interaction with Su(fu). Indeed, fuI alleles which are suppressed by Su(fu) mutations are defined by inframe alterations of the N-terminal catalytic domain whereas the C-terminal domain is missing or altered in all fuII alleles. An unregulated FuII protein, which can be limited to the 80 N-terminal amino acids of the kinase domain, would be responsible for the neomorphic costal-2 phenotype displayed by the fuII-Su(fu) interaction. We propose that the Fu C-terminal domain can differentially regulate the Fu catalytic domain according to cell position in the parasegment