Upregulation of asparagine synthetase fails to avert cell cycle arrest induced by L-asparaginase in TEL/AML1-positive leukaemic cells

Reply to Stams et al

“…In their original letter 1 commenting to our paper, 2 Stams et al showed they failed to confirm statistical difference in asparagine synthetase (AS) expression levels in TEL/AML1 pos paediatric ALL patients with or without subsequent relapses. This difference might be considered clinically relevant since data on patients from different protocols are compared.…”

Mutations in Subunit Interface and B-cell Epitopes Improve Antileukemic Activities of Escherichia coli Asparaginase-II

“…5F). phase (37,38). We therefore studied the growth behavior of MV4:11 cells after treatment with EcA variants by flow cytometry.…”

Accurate detection of Asparagine Synthetase (ASNS) using quantitative real-time PCR (qRT-PCR), without requiring DNaseI treatment

“…The methodology favoured for measuring ASNS expression has been quantitative real-time PCR (qRT-PCR). [2][3][4] This technique presents numerous difficulties in application, particularly in the normalization of results and the use of reference genes, as recently reviewed. 5 Indeed, using variations of the method, a number of workers have drawn differing conclusions from studies of leukemic cells in short-term culture and in marrow specimens.…”

“…5 Indeed, using variations of the method, a number of workers have drawn differing conclusions from studies of leukemic cells in short-term culture and in marrow specimens. [2][3][4] In addition, an examination of the mRNA and genomic sequences for ASNS shows additional factors that could contribute to the uncertainty. We therefore propose a simplified method for this assay in which these features are taken into account.…”

“…Alternatively, Krejci recently employed a technique that circumvented the PCg problem by careful design of ASNS primers and use of b2-microglobin. 4 However, as b2-microglobin has a variable expression pattern it has been suggested that it may not be effective as a reference gene. 6 We therefore demonstrate the use of a recently published method that permits the use of common reference genes and takes into account the issues raised.…”