Stat5b in Lymphomagenesis: Mechanistic and Therapeutic Implications

Stat5b 在淋巴瘤发生中的作用：机制和治疗意义

• 批准号: 7788533
• 负责人: John A Kelly
• 金额: --
• 依托单位: WHITE RIVER JUNCTION VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-10-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7788533
• 关键词: Acceleration; Address; Age; Apoptotic; B-Cell Lymphomas; Biology; CD8B1 gene; Calcineurin; Calcineurin inhibitor; Cell Proliferation; Cell Survival; Cells; Cessation of life; Combined Modality Therapy; Cyclosporine; Cytokine Receptors; Cytokine Signaling; Data; Defect; Development; Disease; Exposure to; Family member; Flow Cytometry; Frequencies; Funding; Gene Expression; Genes; Growth; Growth Factor; Growth and Development function; Hematopoietic Cell Growth Factors; Hodgkin Disease; Human; Immunodeficient Mouse; In Vitro; Interleukin-7; Lead; Ligands; Lymphoma; Lymphomagenesis; Magnetism; Maintenance; Major Histocompatibility Complex; Malignant - descriptor; Malignant Neoplasms; Mediating; Modeling; Monitor; Mus; Non-Hodgkin' s Lymphoma; Oncogenic; Pathway interactions; Play; Population; Prior Therapy; Process; Proteins; Receptor Signaling; Role; Services; Signal Pathway; Signal Transduction; Signaling Molecule; Site; Staging; Stat5 protein; Stem Cell Factor; Stromal Cells; Surface; T-Cell Development; T-Cell Lymphoma; T-Cell Receptor; Testing; Therapeutic; Thymic epithelial cell; Time; Transgenes; Transgenic Mice; Transgenic Organisms; United States; Vascular Endothelial Growth Factor Receptor-1; Veterans; Vietnam; Work; agent orange; alpha chain interleukin-7 receptor; apogossypol; base; cell growth; cytokine; in vivo; inhibitor/antagonist; insight; notch protein; novel therapeutic intervention; public health relevance; research study; subcutaneous; thymocyte

DESCRIPTION (provided by applicant): We previously demonstrated the oncogenic potential of Stat5, with thymic lymphoblastic lymphomas developing in a significant proportion of transgenic (TG) mice over-expressing Stat5a or Stat5b in lymphocytes1. With our current Merit Review funding we investigated the mechanism of Stat5-mediated lymphomagenesis by exploring the contributions of major histocompatibility complex (MHC)/T-cell receptor (TCR) and pre-TCR signals. We demonstrated that Stat5b TG mice unexpectedly develop CD8+ lymphoma in the absence of either pre-TCR signaling or normal thymic MHC/TCR signaling. Indeed, acceleration of Stat5b transgene-mediated lymphoma occurred on TCR1-/- and pre-TCR1-/- backgrounds2. These data support our hypothesis: alterations in T-cell development cooperate with cytokine/growth factor-mediated pathways in immature thymocytes to give rise to lymphoblastic T-cell lymphomas in Stat5b TG mice. In this proposal we will extend these studies to explore the signaling mechanisms and genes involved in transformation of immature thymocytes in lymphoblastic lymphoma. Importantly, we have demonstrated the ability of Jak and calcineurin inhibitors to decrease proliferation of Stat5b TG thymocytes in vitro. Inhibition of signaling pathways including the Jak/Stat5 pathway provides a novel therapeutic approach to lymphoma. Aim 1: Test the hypothesis that cytokine/growth factor-mediated transformation occurs at or prior to the immature single positive (ISP) stage. To expand our understanding of Stat5b-mediated lymphomagenesis, we will determine the site of transformation. This will allow us to examine phenotypic changes and gene expression associated with transformation. Moreover, we will compare the effects of hematopoietic growth factors and cytokines on Stat5b TG and WT immature populations. Sub-Aim 1: Define the population and developmental stage of lymphoma cells. We will enrich immature thymic and BM populations using a combination of magnetic separation and flow cytometry. These populations will be examined for surface expression of phenotypic markers as well as gene expression of lineage specific genes. Growth of subcutaneously (s.q.) injected cells will define the malignant subpopulations. Subaim 2: Define requirements for growth and development of immature thymic precursors in Stat5b TG mice. Enriched immature populations will be cultured with stromal cells expressing the Notch delta like ligand (OP9-DL1) along with cytokines (IL-7), and growth factors (stem cell factor [SCF], fms-like tyrosine- kinase 3 [Flt3] ligand). We will examine cell growth, development, and phenotypic changes over time. Aim 2. Test the hypothesis that IL-7/Jak signaling contributes to Stat5-mediated lymphomas. To clarify the role of IL-7 signaling in Stat5b-mediated lymphoma we will cross Stat5b TG mice onto IL-7R1Y449 mice. These mice cannot signal through Stat5 but have preserved T-cell development. Aim 3. Inhibit Stat5b TG lymphoma in vivo. Our data demonstrate that signals downstream of TCR and cytokine receptors promote lymphoma cell proliferation. Moreover, Stat5 up-regulates anti-apoptotic Bcl-2 family members. Thus, we propose to use a combination of therapies targeting cytokine (CP-690550), calcineurin (Cyclosporin A) and Bcl-2 family members (apogossypol). With these studies we will better define the timing and stage of transformation. We will determine the contribution of Notch1, growth factors and cytokine signaling to the process. Using multiple targeted therapies based on evolving understanding of lymphomagenesis, we will inhibit Stat5-mediated lymphoma in vivo. These experiments have the potential to advance the therapeutic approaches in lymphoma and other malignancies. PUBLIC HEALTH RELEVANCE: Stat5 is associated with a wide variety of human malignancies, including non-Hodgkin's lymphoma (NHL). NHL is the sixth most common cancer in the United States with 66,120 estimated new cases and 19,160 deaths from NHL in 2008. Moreover, Hodgkin's and non-Hodgkin's lymphoma are two of the ten diseases and conditions recognized by the VA as service-connected for Vietnam Veterans, based on their exposure to Agent Orange. We propose to analyze the mechanisms by which Stat5 mediated signaling results in lymphoma, and to determine the requirement for Jak/Stat5 signaling in the maintenance of lymphoma cell survival. Using these mechanistic insights we will inhibit Stat5b TG-mediated lymphoma in vivo. These studies will provide insights into the biology of lymphoma, and potentially lead to new therapies for this disease.

描述（由申请人提供）： 我们先前证明了Stat 5的致癌潜力，在淋巴细胞中过度表达Stat 5a或Stat 5 b的转基因（TG）小鼠中，胸腺淋巴母细胞淋巴瘤的发生率很高1。在我们目前的Merit Review资助下，我们通过探索主要组织相容性复合体（MHC）/T细胞受体（TCR）和前TCR信号的贡献来研究Stat 5介导的淋巴瘤发生的机制。我们证明了Stat 5 b TG小鼠在没有前TCR信号或正常胸腺MHC/TCR信号的情况下意外地发展出CD 8+淋巴瘤。事实上，Stat 5 b转基因介导的淋巴瘤的加速发生在TCR 1-/-和前TCR 1-/-背景2。这些数据支持我们的假设：T细胞发育的改变与未成熟胸腺细胞中细胞因子/生长因子介导的途径合作，在Stat 5 b TG小鼠中引起淋巴母细胞性T细胞淋巴瘤。在这个建议中，我们将扩展这些研究，以探索信号机制和基因参与转化的未成熟胸腺细胞在淋巴母细胞淋巴瘤。重要的是，我们已经证明了Jak和钙调磷酸酶抑制剂在体外降低Stat 5 b TG胸腺细胞增殖的能力。抑制包括Jak/Stat 5通路在内的信号通路为淋巴瘤提供了一种新的治疗方法。目的1：检验细胞因子/生长因子介导的转化发生在未成熟单阳性（ISP）阶段或之前的假设。为了扩大我们对Stat 5 b介导的淋巴瘤发生的理解，我们将确定转化位点。这将使我们能够检查与转化相关的表型变化和基因表达。此外，我们将比较造血生长因子和细胞因子对Stat 5 b TG和WT未成熟群体的影响。子目标1：定义淋巴瘤细胞的群体和发育阶段。我们将使用磁分离和流式细胞术的组合来富集未成熟的胸腺和BM群体。将检查这些群体的表型标志物的表面表达以及谱系特异性基因的基因表达。皮下生长（s.q.）注射的细胞将确定恶性亚群。Subaim 2：定义Stat 5 b TG小鼠中未成熟胸腺前体的生长和发育要求。富集的未成熟群体将与表达Notch δ样配体（OP 9-DL 1）的基质细胞一起培养，沿着细胞因子（IL-7）和生长因子（干细胞因子[SCF]、fms样酪氨酸激酶3 [Flt 3]配体）。我们将检查细胞生长，发育和表型随时间的变化。目标二。检验IL-7/Jak信号传导促进Stat 5介导的淋巴瘤的假设。为了阐明IL-7信号传导在Stat 5 b介导的淋巴瘤中的作用，我们将Stat 5 b TG小鼠与IL-7 R1 Y 449小鼠杂交。这些小鼠无法通过Stat 5发出信号，但保留了T细胞发育。目标3。抑制体内Stat 5 b TG淋巴瘤。我们的数据表明，TCR和细胞因子受体下游的信号促进淋巴瘤细胞增殖。此外，Stat 5上调抗凋亡Bcl-2家族成员。因此，我们建议使用靶向细胞因子（CP-690550）、钙调神经磷酸酶（环孢菌素A）和Bcl-2家族成员（阿朴棉酚）的疗法的组合。通过这些研究，我们将更好地确定转型的时间和阶段。我们将确定Notch 1、生长因子和细胞因子信号传导对该过程的贡献。基于对淋巴瘤发生的不断理解，我们将使用多种靶向疗法在体内抑制Stat 5介导的淋巴瘤。这些实验有可能推进淋巴瘤和其他恶性肿瘤的治疗方法。 公共卫生相关性： Stat 5与多种人类恶性肿瘤相关，包括非霍奇金淋巴瘤（NHL）。NHL是美国第六常见的癌症，2008年估计有66，120例新病例和19，160例NHL死亡。此外，霍奇金淋巴瘤和非霍奇金淋巴瘤是退伍军人事务部根据他们接触橙子剂的情况确定的与越战退伍军人服务有关的十种疾病和病症中的两种。我们建议分析Stat 5介导的信号传导导致淋巴瘤的机制，并确定Jak/Stat 5信号传导在维持淋巴瘤细胞存活中的需求。使用这些机制的见解，我们将抑制Stat 5 b TG介导的淋巴瘤在体内。这些研究将提供对淋巴瘤生物学的见解，并可能导致这种疾病的新疗法。