Project description:This SuperSeries is composed of the following subset Series: GSE4070: Clinical acute lymphoblastic leukemia samples (untreated) with known asparaginase LC50 values GSE4071: Clinical pediatric acute lymphoblastic leukemia samples after in vitro exposure to L-asparaginase GSE4072: L-asparaginase exposure in acute lymphoblastic leukemia cell lines time series Abstract: To investigate the effect of l-asparaginase on acute lymphoblastic leukemia (ALL), we used cDNA microarrays to obtain a genome-wide view of gene expression both at baseline and after in vitro exposure to l-asparaginase in cell lines and pediatric ALL samples. In 16 cell lines, a baseline gene expression pattern distinguished l-asparaginase sensitivity from resistance. However, for 28 pediatric ALL samples, no consistent baseline expression pattern was associated with sensitivity to l-asparaginase. In particular, baseline expression of asparagine synthetase (ASNS) was not predictive of response to l-asparaginase. After exposure to l-asparaginase, 5 cell lines and 10 clinical samples exhibited very similar changes in the expression of a large number of genes. However, the gene expression changes occurred more slowly in the clinical samples. These changes included a consistent increase in expression of tRNA synthetases and solute transporters and activating transcription factor and CCAAT/enhancer binding protein family members, a response similar to that observed with amino acid starvation. There was also a consistent decrease in many genes associated with proliferation. Taken together, the changes seem to reflect a consistent coordinated response to asparagine starvation in both cell lines and clinical samples. Importantly, in the clinical samples, increased expression of ASNS after l-asparaginase exposure was not associated with in vitro resistance to l-asparaginase, indicating that ASNS-independent mechanisms of in vitro l-asparaginase resistance are common in ALL. These results suggest that targeting particular genes involved in the response to amino acid starvation in ALL cells may provide a novel way to overcome l-asparaginase resistance. Refer to individual Series
Project description:Abstract: To investigate the effect of l-asparaginase on acute lymphoblastic leukemia (ALL), we used cDNA microarrays to obtain a genome-wide view of gene expression both at baseline and after in vitro exposure to l-asparaginase in cell lines and pediatric ALL samples. In 16 cell lines, a baseline gene expression pattern distinguished l-asparaginase sensitivity from resistance. However, for 28 pediatric ALL samples, no consistent baseline expression pattern was associated with sensitivity to l-asparaginase. In particular, baseline expression of asparagine synthetase (ASNS) was not predictive of response to l-asparaginase. After exposure to l-asparaginase, 5 cell lines and 10 clinical samples exhibited very similar changes in the expression of a large number of genes. However, the gene expression changes occurred more slowly in the clinical samples. These changes included a consistent increase in expression of tRNA synthetases and solute transporters and activating transcription factor and CCAAT/enhancer binding protein family members, a response similar to that observed with amino acid starvation. There was also a consistent decrease in many genes associated with proliferation. Taken together, the changes seem to reflect a consistent coordinated response to asparagine starvation in both cell lines and clinical samples. Importantly, in the clinical samples, increased expression of ASNS after l-asparaginase exposure was not associated with in vitro resistance to l-asparaginase, indicating that ASNS-independent mechanisms of in vitro l-asparaginase resistance are common in ALL. These results suggest that targeting particular genes involved in the response to amino acid starvation in ALL cells may provide a novel way to overcome l-asparaginase resistance. This SuperSeries is composed of the SubSeries listed below.
Project description:Samples of pediatric acute lymphoblastic leukemia obtained from patients at diagnosis. All samples contain at least 77% blasts. Asparaginase LC50 values were determined for each of these samples. (LC50 was determined on a different aliquot of the same sample.)
Project description:Samples of pediatric acute lymphoblastic leukemia obtained from patients at diagnosis. All samples contain at least 77% blasts. Asparaginase LC50 values were determined for each of these samples. (LC50 was determined on a different aliquot of the same sample.)
Project description:Time series of in vitro 2 IU/ml L-asparaginase exposure in acute lymphoblastic leukemia cell lines. Groups of assays that are related as part of a time series. Keywords: time_series_design
Project description:Time series of in vitro 2 IU/ml L-asparaginase exposure in acute lymphoblastic leukemia cell lines. Groups of assays that are related as part of a time series. Using regression correlation
Project description:Samples of pediatric acute lymphoblastic leukemia. All samples contain at least 90% blasts. Each sample was split into two flasks, one of which was exposed to 2IU/ml of L-asparaginase. The other flask served as a control. Cells were lysed at the times indicated.
