Browsing by Author "Rodriguez, Sonia"

Now showing 1 - 4 of 4
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    Notch-dependent repression of miR-155 in the bone marrow niche regulates hematopoiesis in an NF-κB-dependent manner
    (Elsevier, 2014-07-03) Wang, Lin; Zhang, Huajia; Rodriguez, Sonia; Cao, Liyun; Parish, Jonathan; Mumaw, Christen; Zollman, Amy; Kamocka, Gosia; Mu, Jian; Chen, Danny Z.; Srour, Edward F.; Chitteti, Brahmananda R.; HogenEsch, Harm; Tu, Xiaolin; Bellido, Teresita M.; Boswell, Scott; Manshouri, Taghi; Verstovsek, Srdan; Yoder, Mervin C.; Kapur, Reuben; Cardoso, Angelo A.; Carlesso, Nadia; Department of Pediatrics, IU School of Medicine
    The microRNA miR-155 has been implicated in regulating inflammatory responses and tumorigenesis, but its precise role in linking inflammation and cancer has remained elusive. Here, we identify a connection between miR-155 and Notch signaling in this context. Loss of Notch signaling in the bone marrow (BM) niche alters hematopoietic homeostasis and leads to lethal myeloproliferative-like disease. Mechanistically, Notch signaling represses miR-155 expression by promoting binding of RBPJ to the miR-155 promoter. Loss of Notch/RBPJ signaling upregulates miR-155 in BM endothelial cells, leading to miR-155-mediated targeting of the nuclear factor κB (NF-κB) inhibitor κB-Ras1, NF-κB activation, and increased proinflammatory cytokine production. Deletion of miR-155 in the stroma of RBPJ(-/-) mice prevented the development of myeloproliferative-like disease and cytokine induction. Analysis of BM from patients carrying myeloproliferative neoplasia also revealed elevated expression of miR-155. Thus, the Notch/miR-155/κB-Ras1/NF-κB axis regulates the inflammatory state of the BM niche and affects the development of myeloproliferative disorders.
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    Protein Tyrosine Phosphatase PRL2 Mediates Notch and Kit Signals in Early T Cell Progenitors
    (Wiley, 2017-04) Kobayashi, Michihiro; Nabinger, Sarah; Bai, Yunpeng; Yoshimoto, Momoko; Gao, Rui; Chen, Sisi; Yao, Chonghua; Dong, Yuanshu; Zhang, Lujuan; Rodriguez, Sonia; Yashiro- Ohtan, Yumi; Pear, Warren S.; Carlesso, Nadia; Yoder, Mervin C.; Kapur, Reuben; Kaplan, Mark H.; Lacorazza, H. Daniel; Zhang, Zhong-Yin; Liu, Yan; Pediatrics, School of Medicine
    The molecular pathways regulating lymphoid priming, fate, and development of multipotent bone marrow hematopoietic stem and progenitor cells (HSPCs) that continuously feed thymic progenitors remain largely unknown. While Notch signal is indispensable for T cell specification and differentiation, the downstream effectors are not well understood. PRL2, a protein tyrosine phosphatase that regulates hematopoietic stem cell proliferation and self-renewal, is highly expressed in murine thymocyte progenitors. Here we demonstrate that protein tyrosine phosphatase PRL2 and receptor tyrosine kinase c-Kit are critical downstream targets and effectors of the canonical Notch/RBPJ pathway in early T cell progenitors. While PRL2 deficiency resulted in moderate defects of thymopoiesis in the steady state, de novo generation of T cells from Prl2 null hematopoietic stem cells was significantly reduced following transplantation. Prl2 null HSPCs also showed impaired T cell differentiation in vitro. We found that Notch/RBPJ signaling upregulated PRL2 as well as c-Kit expression in T cell progenitors. Further, PRL2 sustains Notch-mediated c-Kit expression and enhances stem cell factor/c-Kit signaling in T cell progenitors, promoting effective DN1-DN2 transition. Thus, we have identified a critical role for PRL2 phosphatase in mediating Notch and c-Kit signals in early T cell progenitors.
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    Sepsis Induces Hematopoietic Stem Cell Exhaustion and Myelosuppression through Distinct Contributions of TRIF and MYD88
    (Elsevier, 2016-06-14) Zhang, Huajia; Rodriguez, Sonia; Wang, Lin; Wang, Soujuan; Serezani, Henrique; Kapur, Reuben; Cardoso, Angelo A.; Carlesso, Nadia; Department of Microbiology & Immunology, IU School of Medicine
    Toll-like receptor 4 (TLR4) plays a central role in host responses to bacterial infection, but the precise mechanism(s) by which its downstream signaling components coordinate the bone marrow response to sepsis is poorly understood. Using mice deficient in TLR4 downstream adapters MYD88 or TRIF, we demonstrate that both cell-autonomous and non-cell-autonomous MYD88 activation are major causes of myelosuppression during sepsis, while having a modest impact on hematopoietic stem cell (HSC) functions. In contrast, cell-intrinsic TRIF activation severely compromises HSC self-renewal without directly affecting myeloid cells. Lipopolysaccharide-induced activation of MYD88 or TRIF contributes to cell-cycle activation of HSC and induces rapid and permanent changes in transcriptional programs, as indicated by persistent downregulation of Spi1 and CebpA expression after transplantation. Thus, distinct mechanisms downstream of TLR4 signaling mediate myelosuppression and HSC exhaustion during sepsis through unique effects of MyD88 and TRIF.
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    Therapeutic targeting of the E3 ubiquitin ligase SKP2 in T-ALL
    (Springer Nature, 2019-11-26) Rodriguez, Sonia; Abundis, Christina; Boccalatte, Francesco; Mehrotra, Purvi; Chiang, Mark Y.; Yui, Mary A.; Wang, Lin; Zhang, Huajia; Zollman, Amy; Bonfim-Silva, Ricardo; Kloetgen, Andreas; Palmer, Joycelynne; Sandusky, George; Wunderlich, Mark; Kaplan, Mark H.; Mulloy, James C.; Marcucci, Guido; Aifantis, Iannis; Cardoso, Angelo A.; Carlesso, Nadia; Medicine, School of Medicine
    Timed degradation of the cyclin-dependent kinase inhibitor p27Kip1 by the E3 ubiquitin ligase F-box protein SKP2 is critical for T-cell progression into cell cycle, coordinating proliferation and differentiation processes. SKP2 expression is regulated by mitogenic stimuli and by Notch signaling, a key pathway in T-cell development and in T-cell acute lymphoblastic leukemia (T-ALL); however, it is not known whether SKP2 plays a role in the development of T-ALL. Here, we determined that SKP2 function is relevant for T-ALL leukemogenesis, whereas is dispensable for T-cell development. Targeted inhibition of SKP2 by genetic deletion or pharmacological blockade markedly inhibited proliferation of human T-ALL cells in vitro and antagonized disease in vivo in murine and xenograft leukemia models, with little effect on normal tissues. We also demonstrate a novel feed forward feedback loop by which Notch and IL-7 signaling cooperatively converge on SKP2 induction and cell cycle activation. These studies show that the Notch/SKP2/p27Kip1 pathway plays a unique role in T-ALL development and provide a proof-of-concept for the use of SKP2 as a new therapeutic target in T-cell acute lymphoblastic leukemia (T-ALL).