Project description:Comparative label free quantitative proteomic analysis using SWATH-MS has been carried out for K562 cells treated with Imatinib (S+IM) against untreated K562 (S) as well as imatinib resistant K562 cells (R). Compariosn of S+IM vs R constitutes Dataset 1 while that of S vs S+IM constitutes dataset 2
Project description:K562 cells untreated (S) and treated (S+IM) with Imatinib as well as sensitive (S+IM) and resistant (R) to imatinib were subjected to labelled quantification by iTRAQ to identify Bcr-Abl downstream signaling components and proteins modulated in resistance respectively
Project description:K562 cells (duplicate cultures A & B) are treated with 50 micromolar hemin for 0, 6, 12, 24, 48, 72 hours followed by RNA extraction and gene expression profiling on Affymetrix human U133A arrays and analysis by MAS 5.0
Project description:Chronic myelogenous leukemia (CML) is a malignant stem cell disease characterized by a reciprocal translocation between chromosome 9 and 22. The selective bcr-abl tyrosine-kinase inhibitor Imatinib has become the therapy of choice for patients with newly diagnosed CML including those previously considered candidates for allogeneic haematopoietic stem cell transplantation. The tyrosine-kinase inhibitor Nilotinib is a derivate of Imatinib with higher potency. To examine the molecular and functional effects of Nilotinib and Imatinib in chronic myelogenous leukemia, we performed gene expression and functional analyses in K562 cells following treatment with the two tyrosine kinase inhibitors. Experiment Overall Design: Affymetrix U133A 2.0 microarrays were used to examine the gene expression profile of K562 cells after in vitro treatment with Imatinib (0.5 µM) or Nilotinib (0.05 µM) for 24 hours. Gene expression data of the treated cells were compared with data of untreated cells.
Project description:K562 cells when grown with erythropeitin do not respond to Imatinib. Here we are comparing the gene expression profile from imatinib resistant and sensitive cells.
Project description:Transcriptional profiling of K562-r comparing control untreated human leukemia cells with human leukemia cells treated with AMN107 and ATO individually or combined.Four timepoints included are 3h,12h,24h,48h, covering the whole time window of K562-r cells responsing to the drug treatment.At the combination of 1.5uM ATO and 8uM AMN107, K562-r cells have the most significant coordinated effects (the apoptosis rate at 72h was 56.41% compared to 12.23% in ATO alone and 29.8% in AMN107 alone.). We studied gene expression series in K562-r cells with or without drug treatments by cDNA microarray analysis. Many genes involved in endoplasmic reticulum (ER) stress signaling, including ATF3, DDIT3, HERPUD1, HSPA5, XBP1 and TXNDC12, were highly up-regulated within 12 h of co-treatment, suggesting that the combination of ATO with AMN107 induced an ER stress response leading to apoptosis later on. Other ER-stress markers like the JNK pathway, which bridges the ER-stress and apoptosis, have been activated. Knock down the initiator of JNK partially alleviate the effects of apoptosis (p<0.05). Co-administering AMN107 and arsenic trioxide, inducing apoptosis via the ER-stress, indicates a novel therapy alternative for the imatinib induced secondary resistance. 17-condition experiment, untreated K562-r vs. Drug-treated K562-r cells, including 4 time points, for each point the untreated and 1.5uM ATO treated,8uM AMN107 treated and both 1.5uM ATO and 8uM AMN107 treated, independently grown and harvested. One replicate per array. Untreated K562-r_0h used to counteracting the background.
Project description:Inhibition of deregulated protein kinases by small molecule drugs has evolved into a major therapeutic strategy for the treatment of human malignancies. Imatinib mesylate has emerged as the leading compound to treat chronic myeloid leukemia (CML), through its inhibition of Bcr- Abl tyrosine kinases, and other cancers. However, resistance to imatinib develops frequently, particularly in late-stage disease and has necessitated the development of new BCR-ABL inhibitors. The synthesis of a new series of phenylaminopyrimidines, structurally related to imatinib showed large interest since the introduction of the nilotibin. To identify the cellular pathways affected by new synthesized compounds, we applied mass spectrometry together with stable isotope labeling by amino acids in cell culture (SILAC) for the comparative study of protein expression in K562 cells that were untreated or treated with imatinib and imatinib derivates. Further, the global proteome of the K562 cells treated with imatinib were quantitatively compared with the cells treated with the new compounds. This study enriched our knowledge about direct cellular targets of kinase selective drugs. Further the results offered important new knowledge for gaining insights into the structural effects of action of the new compounds. Samples were analyzed on a longer column (30cm) and a longer gradient (180min). Raw data files were processed with Mascot distiller 2.3. The mgf files were searched with Mascot daemon 2.3. The quantification was also done by Mascot Distiller. All data was stored in ms_lims. The manual validation of false peptide ratios was done with Rover (part of ms_lims). Fixed modifications: none. Variable modifications: acetylation of peptide N-terminus, pyroglutamate formation of N-terminal glutamine, methionine oxidation. Enzyme: trypsine with one missed cleavage allowed. Precursor mass tolerance: 10 ppm. Peptide fragment mass tolerance: 0.5 Da Quantitation method: SILAC arginine and lysine +6 Da. Overview of the 17 different analyses: B SK23 vs DMSO C Y22 vs DMSO D SK20 vs DMSO E Y18 vs DMSO I SK20 vs DMSO K Y18 vs DMSO O Y22 vs DMSO R Imatinib vs Water Z Imatinib vs Water J SK20 vs Imatinib M SK23 vs Imatinib N Y22 vs Imatinib P SK23 vs Imatinib Q Y18 vs Imatinib S Y22 vs Imatinib T SK20 vs Imatinib Y Y18 vs Imatinib
Project description:Using a microarray-based miRNA profiling, we found in a model of chronic myeloid leukemia (CML) that the activity of the oncoprotein BCR-ABL1 regulates the expression of miR-21, a "onco-microRNA" known to be overexpressed in numerous cancers. This relies on the phosphorylation status of STAT5, a transcription factor known to be activated by the kinase activity of BCR-ABL1. Mir-21 regulates the expression of PDCD4 (programmed cell death protein 4), a tumor suppressor identified here through a proteomics approach The microRNA repertoire of K562 cells having been either not treated (n=3) or treated (n=3) with the tyrosine kinase inhibitor Imatinib (1microM, 24h) was studied using Agilent microRNA V2 microarrays
Project description:The aim of the analysis is to study the relationship between tyrosine kinase inhibitor (TKI) resistance mechanism and phenotypic plasticity in the TKI-resistant and parental chronic myeloid leukemia K562 cell lines, in the presence and absence of imatinib. Results provide insight into the molecular mechanisms underlying the acquisition of cancer cell plasticity.