Frequent over-expression and mutation of B-cell receptor (BCR) signaling molecules contributes to the pro survival phenotype and aggressive nature of diffuse large B-cell lymphoma (DLBCL). To understand the mechanisms that underlay the deregulation of this important pathway and ultimately improve the outcome of patients with this often refractory and relapse prone disease, we developed a therapeutic research program to investigate the role of and target DNA secondary structures within BCR regulatory genes. We propose that promoter G-quadruplex (G4) DNA structures regulate expression of BCR-related genes and can be targeted to silence oncogenic signaling. In preliminary studies, we discovered the presence of G4 forming sequences Nithin BCR signaling genes, CARD11 and MYDBB. We screened the NCI Diversity Set library of compounds 3nd identified small molecules that stabilize these structures, lower mRNA levels, and sensitize DLBCL cells to standard chemotherapy. Here, we will use these G4 stabilizing compounds as molecular tools to define the 11echanism by which these DNA structures regulate the BCR pathway in DLBCL cell line and patient derived :ells in vitro. We will determine the subsequent effects on BCR signaling by performing phospho-proteomics to 3ssess repression of downstream BCR molecules including NF-KB and ERK. We will then translate these studies into a DLBCL patient derived xenograft mouse model to demonstrate the extent of silencing CARD11 md MYDBB expression on tumor growth and chemosensitivity. We will also test our hypothesis that G4s play a ole in the BCR mutations induced by the antibody diversification enzyme, activation induced cytidine foaminase (AID). In support of this idea, we found a genome wide enrichment for G4 forming sequences Nithin AID hotspots that overlay with oncogene mutations in patient samples. We will now define the nvolvement of G4 structures in the mechanism for AID induced CARD11 and MYDBB mutations by evaluating he recognition and binding of AID to G4 structures with binding assays, spectroscopy, and ChlP-sequencing. Ne will perform functional assays where the G4 sequences are used as bait in an established GFP mutation eporter assay in the presence of AID to assess how G4s impact mutation frequency. Our findings will provide nsight into the mechanisms leading to the aberrant BCR signaling and demonstrate the CARD11 and MYDBB 34s can serve as therapeutic targets for inhibiting these oncogenic signals and tumor growth. Transcriptionally egulating BCR signaling genes has high potential for uncovering a treatment breakthrough for the clinical nanagement of patients with BCR-dependent DLBCL. This work will also establish models for continued nvestigations and accumulate data for a competitive R01 application.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Exploratory Grants (P20)
Project #
Application #
Study Section
Special Emphasis Panel (ZGM1)
Program Officer
Barthold, Julia Spencer
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Arkansas Children's Hospital Research Institute
Little Rock
United States
Zip Code
Zhang, Xin; Zhang, Suping; Liu, Xingui et al. (2018) Oxidation resistance 1 is a novel senolytic target. Aging Cell :e12780
Lo, Dennis; Kennedy, Joshua L; Kurten, Richard C et al. (2018) Modulation of airway hyperresponsiveness by rhinovirus exposure. Respir Res 19:208
Salinas, Eduardo; Gupta, Arundhati; Sifford, Jeffrey M et al. (2018) Conditional mutagenesis in vivo reveals cell type- and infection stage-specific requirements for LANA in chronic MHV68 infection. PLoS Pathog 14:e1006865
Kennedy, Joshua L; Koziol-White, Cynthia J; Jeffus, Susanne et al. (2018) Effects of rhinovirus 39 infection on airway hyperresponsiveness to carbachol in human airways precision cut lung slices. J Allergy Clin Immunol 141:1887-1890.e1
Barham, Caroline; Fil, Daniel; Byrum, Stephanie D et al. (2018) RNA-Seq Analysis of Spinal Cord Tissues from hPFN1G118V Transgenic Mouse Model of ALS at Pre-symptomatic and End-Stages of Disease. Sci Rep 8:13737
Kriss, Crystina L; Gregory-Lott, Emily; Storey, Aaron J et al. (2018) In Vivo Metabolic Tracing Demonstrates the Site-Specific Contribution of Hepatic Ethanol Metabolism to Histone Acetylation. Alcohol Clin Exp Res 42:1909-1923
Dinwiddie, Darrell L; Denson, Jesse L; Kennedy, Joshua L (2018) Role of the Airway Microbiome in Respiratory Infections and Asthma in Children. Pediatr Allergy Immunol Pulmonol 31:236-240
Byrum, Stephanie D; Loughran, Allister J; Beenken, Karen E et al. (2018) Label-Free Proteomic Approach to Characterize Protease-Dependent and -Independent Effects of sarA Inactivation on the Staphylococcus aureus Exoproteome. J Proteome Res 17:3384-3395
Mao, Xiao W; Byrum, Stephanie; Nishiyama, Nina C et al. (2018) Impact of Spaceflight and Artificial Gravity on the Mouse Retina: Biochemical and Proteomic Analysis. Int J Mol Sci 19:
Vlachos, Adrianna; Osorio, Diana S; Atsidaftos, Evangelia et al. (2018) Increased Prevalence of Congenital Heart Disease in Children With Diamond Blackfan Anemia Suggests Unrecognized Diamond Blackfan Anemia as a Cause of Congenital Heart Disease in the General Population: A Report of the Diamond Blackfan Anemia Registry. Circ Genom Precis Med 11:e002044

Showing the most recent 10 out of 16 publications