Dynamic Mathematical Modeling of IL13-Induced Signaling in Hodgkin and Primary Mediastinal B-Cell Lymphoma Allows Prediction of Therapeutic Targets

Division of Systems Biology of Signal Transduction, DKFZ-ZMBH Alliance and Molecular Genetics, German Cancer Research Center, Heidelberg, Germany.
Cancer Research (Impact Factor: 9.33). 02/2011; 71(3):693-704. DOI: 10.1158/0008-5472.CAN-10-2987
Source: PubMed


Primary mediastinal B-cell lymphoma (PMBL) and classical Hodgkin lymphoma (cHL) share a frequent constitutive activation of JAK (Janus kinase)/STAT signaling pathway. Because of complex, nonlinear relations within the pathway, key dynamic properties remained to be identified to predict possible strategies for intervention. We report the development of dynamic pathway models based on quantitative data collected on signaling components of JAK/STAT pathway in two lymphoma-derived cell lines, MedB-1 and L1236, representative of PMBL and cHL, respectively. We show that the amounts of STAT5 and STAT6 are higher whereas those of SHP1 are lower in the two lymphoma cell lines than in normal B cells. Distinctively, L1236 cells harbor more JAK2 and less SHP1 molecules per cell than MedB-1 or control cells. In both lymphoma cell lines, we observe interleukin-13 (IL13)-induced activation of IL4 receptor α, JAK2, and STAT5, but not of STAT6. Genome-wide, 11 early and 16 sustained genes are upregulated by IL13 in both lymphoma cell lines. Specifically, the known STAT-inducible negative regulators CISH and SOCS3 are upregulated within 2 hours in MedB-1 but not in L1236 cells. On the basis of this detailed quantitative information, we established two mathematical models, MedB-1 and L1236 model, able to describe the respective experimental data. Most of the model parameters are identifiable and therefore the models are predictive. Sensitivity analysis of the model identifies six possible therapeutic targets able to reduce gene expression levels in L1236 cells and three in MedB-1. We experimentally confirm reduction in target gene expression in response to inhibition of STAT5 phosphorylation, thereby validating one of the predicted targets.

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    • "e.g. [4] [5] [6] [7] [8] [9]. They are characterized by a functional relationship between the current state of the system x(t) ∈ R N at time point t and its time derivative ˙ x(t): ˙ x(t) = f (t, x(t), u(t), ζ) . "
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    • "The Bayesian framework for the compartmental model analysis developed in the present work is directly applicable to a personalized dose assessment and the uncertainty quantification if a person-specific monitoring is requested. More generally, the presented methodology is suitable for any ODE-based model selection task, such as the modeling of protein signaling, gene regulation, or drug processing [47], nowadays frequently put forward in systems biology [48,49] or pharmacogenetics [50]. "
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    • "CREB bZIP 40,000 rat PC12 pheochromocytoma cell line Conkright et al., 2003 E2A bHLH 30,000 murine primary pro B cells Zhuang et al., 2004 GR Receptor zinc finger 13,000 murine primary macrophage Salkowski and Vogel, 1992 Ikaros C2H2 zinc finger 250,000 murine thymocytes Bradley et al., 2003 NF-kB p65 Rel 250,000 murine macrophage Bradley et al., 2003 TR Receptor zinc finger 4,000 rat liver tissue Oppenheimer et al., 1974 Human AP-2a AP-2 200,000 HepG2 hepatocarcinoma cell line Egener et al., 2005 ER Receptor zinc finger 11,000; 260,000 ZR-75-1 breast cancer cell line; MCF-7 breast carcinoma cell line Reese and Katzenellenbogen, 1992 fos bZIP 4,000 NA De Togni et al., 1988 GR Receptor zinc finger 100,000 HeLa carcinoma cell line van Steensel et al., 1995 myc bHLH-ZIP 60,000; 140,000 MCF-7 breast carcinoma cell line; HCT-116 colon carcinoma cell line Nieddu et al., 2005 MyoD bHLH 50,000 RD rhabdomyosarcoma cell line S. Tapscott, personal communication NF-kB p65 Rel 120,000 TNFa stimulated T-leukemia cell line Hottiger et al., 1998 p53 p53 21,000; 160,000 LB19 B-lymphoblastoid cell line; MCF-7 breast carcinoma cell line Ma et al., 2005 PR Receptor zinc finger 200,000 T4D7 breast carcinoma cell line Nordeen et al., 1989 P-Smad2 SMAD 20,000 TGF-b stimulated keratinocyte cell line Zi et al., 2011 STAT2 STAT 150,000 INFa stimulated T-leukemia cell line Hottiger et al., 1998 STAT6 STAT 10,000; 200,000 CD19+ primary B cells; B cell lymphoma cell line Raia et al., 2011 Tcf-1 HMG 3,900,000 Jurkat T-leukemia cell line Van de Wetering et al., 1996 Developmental Cell 21, October 18, 2011 ª2011 Elsevier Inc. 617 Developmental Cell Perspective accessible DNA by electrostatic, sequence-independent interactions (K D $10 À6 M) (Lin and Riggs, 1975; von Hippel, 2004; von Hippel et al., 1974) and other molecules by sequencespecific interactions with many of tens of thousands of moderate and high-affinity recognition sites (K D < 10 À8 M) (e.g., Li et al., 2011). Methods such as FRAP, in vivo single-molecule analysis, and in vivo footprinting have been used to establish that indeed at least 90% of the molecules of each sequence specific DNA binding protein examined are bound to DNA in cells at any instant (Elf et al., 2007; Kao-Huang et al., 1977; Phair et al., 2004; Yang and Nash, 1995). "
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