Recent Submissions

  • Microtubule disruption reduces tumor cell migration and invasion while microtubule stabilizers increase metastasis phenotypes (2)

    Thompson, Keyata N.; Campbell, Riyan N.; Ju, Julia A.; Annis, David A.; Chang, Katarina T.; Mull, Makenzy L.; Stemberger, Megan; Vitolo, Michele I.; Martin, Stuart S. (2022-06)
  • Inhibition of Autophagy in Microglia & Macrophages Exacerbates Neuroinflammation and Functional Defects Following Traumatic Brain Injury

    Hegdekar, Nivedita; Sarkar, Chinmoy, Ph.D.; Bustos, Sabrina; Ritzel, Rodney M.; Hanscom, Marie; Ravishankar, Prarthana; Philkana, Deepika; Wu, Junfang; Loane, David J.; Lipinski, Marta M. (2022-06)
  • Tubulin-based microtentacles aid in heterotypic neutrophil-CTC clustering (2)

    Ju, Julia A.; Thompson, Keyata N.; Vitolo, Michele I.; Martin, Stuart S. (2022-06)
  • Pseudomonas aeruginosa lipid A structural variants impact bacterial outer membrane porin expression

    Hofstaedter, Casey E.; Chandler, Courtney E.; Kim, Peter; Rasko, David A.; Harro, Janette M.; Ernst, Robert K. (2022-06)
  • Tick Hemocytes at the Single Cell Level

    Rolandelli, Agustin; Bogale, Haikel N.; Samaddar, Sourabh; O’Neal, Anya J.; Singh, Nisha; Butler, L. Rainer; Marnin, Liron; Mendes, M. Tays; Ferraz, Camila R.; Paz, Francy E. Cabrera; et al. (2022)
  • Rickettsia species secret effector(s) that modulates intracellular trafficking to establish a replicative niche in host cytosol

    Sadik, Mohammad; Ullah, Saif; Voss, Oliver H.; Rahman, M. Sayeedur; Azad, Abdu F. (2022-06)
  • Lipid Accumulation in Mononuclear Phagocytes Impairs Autophagy and Contributes to Inflammation after Traumatic Brain Injury

    Mehrabani-Tabari, Amir; Hegdekar, Nivedita; Sarkar, Chinmoy, Ph.D.; Jones, Jace W., 1978-; Kane, Maureen A.; Lipinski, Marta M. (2022-06)
  • A Pleiotropic Metabolite Affects Microbial Infection and Arthropod Vector Fitness

    Samaddar, Sourabh; Marnin, Liron; Singh, Nisha; Rolandelli, Agustin; O'Neill, Anya J.; Butler, L. Rainer; Pedra, Joao H. F. (2022-06)
    Viewing interspecies relationships through the lens of bioenergetics enables a flexible conceptual framework to understand why virulence is context-dependent in arthropod-borne diseases. Here, we engineered a system of metabolic interdependence in Ixodes scapularis where nutrients were allocated according to the glycolytic or oxidative phosphorylation cellular state. The rickettsial agent Anaplasma phagocytophilum and the Lyme disease spirochete Borrelia burgdorferi induced glycolysis during infection and inhibition of oxidative phosphorylation enhanced microbial colonization of tick cells. Through an unbiased metabolomics approach, we discovered that β-aminoisobutyric acid (BAIBA) was an important metabolite for tick-microbe interactions. Whereas distinct levels of BAIBA affected tick weight and survival in vivo, disrupting BAIBA levels through genetic manipulation of catabolic enzymes reduced bacterial infection and restores tick fitness. Collectively, the metabolite BAIBA draws antagonistic pleiotropy on seemingly unrelated evolutionary traits in Ixodes scapularis ticks. Bioenergetics and resource allocation have yet to be explored as a strategy to constrain the public health burden of arthropod-borne diseases.
  • Muscle-Specific Functional Deficits and Lifelong Fibrosis in Response to Pediatric Radiotherapy and Rhabdomyosarcoma Tumor Elimination

    Kallenbach, Jacob G.; Bachman, John F.; Blanc, Roméo S.; O’Connor, Thomas; Furati, Esraa; Hernady, Eric; Johnston, Carl J.; Dirksen, Robert T.; Chakkalakal, Joe V. (2022-06)
  • Early muscle activation of the hip abductors in older adults with fall risk.

    Lanza, Marcel B.; Frakes, Nathan; Gray, Vicki L. (2022-06-21)
  • Mechano-response via ATP alters calcium signaling in breast epithelial cells with oncogenic KRas mutation

    Mull, Makenzy L.; Pratt, Stephen; Lee, Rachel M.; Gad, Abanoub; Stemberger, Megan; Chang, Katarina T.; Annis, David A.; Thompson, Keyata N.; Vitolo, Michele I.; Boyman, Liron; et al. (2022)
    The majority of breast cancer patient deaths occur when tumor cells migrate away from the primary tumors and disseminate metastatically. Cancer cells at the invasive front mimic the behaviors of non-tumorigenic epithelial cells at wound edges but show less coordinated migration comparatively. While most wound healing studies use a timeframe of 24- 48 hours, our previous studies have shown that ATP released from wounded cells initiates a calcium (Ca2+) signal within seconds that spreads to neighboring cells through activation of the P2Y2 surface receptor. RNAseq data of MCF10A mammary epithelial cells with stepwise mutations of PTEN knockout and KRas activation alone or in combination, demonstrate that P2Y2 is downregulated specifically by active KRas. Fluorescence microscopy was used to measure Ca2+ signaling and mitochondrial membrane potential in parental and mutant MCF10A cells. Change in total fluorescence was measured and compared to baseline using Fluo-4, a Ca2+ fluorescent indicator, and TMRM (, methyl ester), a fluorescent mitochondrial membrane potential dye on Nikon analysis software. We show that KRas activation disrupts ATP stimulation and Ca2+ signaling. This change was further quantified using a FlexStation III plate reader with Fluo-4 to read specific fluorescent changes in Ca2+ after ATP addition. ATP-stimulated Ca2+ was also disrupted in other breast tumor cell lines harboring Ras activating mutations, MDA-MB-231 and MDA-MB-436, both showing a similar decrease in P2Y2 expression. These data show that ATP stimulation can be used to further understand the differences in Ca2+ signaling and mechanical-response between normal breast epithelial cells and cancer cells. Clarifying these molecular mechanisms could reveal targets for new cancer treatments, especially since 90% of human tumors are epithelial carcinomas.
  • Interferon-free Hepatitis C treatment increases surrogate of cardiovascular disease risk in Black Veterans

    Mathur, Poonam; George, Nivya; Kaplan, R.; Theppote, Amanda; Kottilil, Shyamasundaran; Wilson, Eleanor, M.D. (2022)
  • Comparing Patients’ Action Stages to Medication Compliance and Tobacco Use Outcomes

    Melamed, Julia; Hallinan, Jayme; Chan, Janet; Khanna, Niharika (2022-06)
  • Targeting Serine Biosynthesis in Combination with Glutamine Modulation to Enhance Cytotoxicity Against Acute Myeloid Leukemia

    Hameed, Kanwal Mahmood; Bollino, Dominique; Emadi, Ashkan (2022-06-09)
    Acute myeloid leukemia (AML) is a heterogeneous hematologic neoplasm characterized by clonal evolution of hematopoietic stem/progenitor cells resulting in disruption of normal blood cell production and function. AML is the most common type of acute leukemia in adults with the cases rising 1.5% each year since 2008. Dismal outcomes despite new treatment options highlights the need for identifying better targets/ treatment strategies. Reprogramming of amino acid metabolism in hematologic malignances contributes to tumor development and maintenance, introducing metabolic liabilities that can be exploited therapeutically. AML exhibits a critical dependence on glutamine for survival and proliferation, therefore glutamine depletion has emerged as a therapeutic strategy. There are multiple ways to target glutamine metabolism in the cell. Asparaginase, an enzyme that hydrolyzes circulating asparagine and glutamine to aspartate and glutamate, respectively, is well-established for the treatment of acute lymphoblastic leukemia (ALL) and has been successfully tested in AML by us and other groups. In response to glutamine depletion induced by asparaginase, AML cells upregulate key enzymes in the serine biosynthesis pathway. The three enzymes involved in the serine biosynthesis pathway are reported to be upregulated in different neoplastic cells, and it has been shown that silencing the rate-limiting enzyme phosphoglycerate dehydrogenase (PHGDH), has a detrimental effect on leukemia cell growth and survival. We hypothesized that in response to glutamine depletion, AML cells upregulate serine biosynthesis as a compensatory pathway and that interference of serine biosynthesis will synergize with glutamine depletion via synthetic lethality to more effectively kill AML cells. In support of our hypothesis, we found that following exposure to asparaginase, plasma serine levels significantly increased in both mice and in AML patients in a clinical trial. Using human AML cell lines, we found that glutamine depletion inhibits cancer cell proliferation/survival and causes a reduction in glutathione, an important cellular antioxidant. Following either glutamine removal from the media or treatment with a crisantaspase, we observed an increase in PHDGH expression, and when we knocked PHGDH out of two AML cell lines using CRISPR-cas9, we found that the cells were significantly more sensitive to glutamine depletion. Ongoing work is focused on the development of a pharmacologic inhibitor of PHGDH to combine with crisantaspase as a novel treatment approach for AML. This work will significantly contribute to the understanding of the role of amino acid regulated metabolic pathways in AML, which may also be extended to other cancers that are dependent on glutamine metabolism.
  • Role of Dual Oxygenase 2 (DUOX2) in preventing PD-L1 upregulation and increasing radiosensitivity of stomach cancer cells

    Martins, Mariana B.; Solano-Gonzalez, Eduardo; Zodda, Andrew; Gerry, Andrew; Tighe, Kayla; Casildo, Andrea; B'lanton, Jasmine; Poirier, Yannick; Carrier, France (2022-06-09)
    Human Stomach cancer cells (NCI-N87) expressing endogenous or downregulated DUOX2 levels were injected into the abdomen of nude mice which were then treated with five 15cGy fractions of Low Dose WART (LD-WART) for three consecutive days. Our data indicate that expression of DUOX2 increased the levels of protein oxidation in mice serum exposed to LD-WART and increased the odds of preventing cancer dissemination by ten-fold. Moreover, downregulation of DUOX2 leads to HIF-1 and PD-L1 up-regulation in human tumors grown in mice. We also observed the same correlation in mice stomach cancer cells (NCC-S192) when DUOX2 was knockdown by CRISPR/Cas9. The upregulation of HIF-1 indicates that these tumors are hypoxic, which contributes to radioresistance. In addition, PD-L1, a downstream target of HIF-1, is also associated with radio-resistance. A mouse angiogenesis profiler array indicated that several angiogenetic factors were upregulated in the DUOX2 positive but not negative tumors in response to LDWART. This could have contributed to increase reoxygenation in the DUOX2 positive tumor and increase radiosensitivity to low dose radiation. The role of LD-WART in the immune response was then investigated in immunocompetent C57BL/6 mice. The mice were exposed to the same regimen of 15cGy LD-WART twice a day for three consecutive days either once or for two consecutive weeks. Samples were then collected one, two, or three weeks later following the last radiation dose. Our data indicate that LD-WART significantly increased CD8+ T cells (Lag3-/PD1-) in the blood and spleen one week following LD-WART and gradually faded off. On the other hand, exposing the mice to two consecutive rounds of LDWRT fail to upregulate the CD8+ T cells.
  • Optimization of Small molecules inhibitors against hnRNP A18, a regulator of protein translation and an immune checkpoint

    Solano-Gonzalez, Eduardo; Fletcher, Steven; Yu, Wenbo; MacKerell, Alexander D., Jr.; Weber, David J., Ph.D.; Carrier, France (2022-06-09)
    We have identified the heterogenous ribonucleoprotein A18 (hnRNP A18) as a regulator of protein translation in cancer cells. hnRNP A18 recognizes a specific RNA signature motif in the 3’UTR of transcripts associated with cancer cells progression as well as CTLA-4, an immune checkpoint. Tissue micro arrays performed on human cancers indicate that hnRNP A18 is over expressed in 40 to 60% of malignant tissue as compared to normal adjacent tissue. Most importantly, down regulation of hnRNP A18 significantly reduces tumor growth in two mouse xenograft models (melanoma and breast cancer). These data indicate that hnRNP A18 is a valid target for anticancer drug development. To this Aim we first solved hnRNP A18 3D structure by NMR and crystallography and then used Computer assisted Drug design to search for potential hnRNP A18 small molecule binders targeting the RNA binding pocket. Four lead compounds that specifically target hnRNP A18 were identified. The compounds compete out hnRNP A18 RNA binding activity and specifically kill cancer cells expressing hnRNP A18 without affecting normal epithelial cells or cancer cells that do not express hnRNP A18. In vitro pharmacokinetics assay however indicate that the compounds are unstable in mouse plasma thus precluding their use into animal models. Three of the lead compounds share a common feature: they are all phenolic esters, and so it is not surprising that they have very limited half-lives in plasma. A three-pronged Medicinal chemistry strategy was then used to improve the compounds stability. First, amide congeners of the ester parent drugs were prepared, second the corresponding phenol metabolites were synthetized, and third five bulky sterically hindered esters analogues of the parent drugs were synthetized. In all, twenty derivatives were synthetized and analyzed by RNA band shift and cell viability. While most derivatives were able to compete out hnRNP A18 RNA binding activity, three analogues remain as potent or slightly better at killing cancer cells than the parent compounds. An in vitro pharmacokinetics assay was then performed on one of the ester derivatives. Our data indicate that the half-life of the ester derivative increased by ten-fold as compared to the parent compound in mouse plasma. This compound is currently being scaled up for efficacy experiments in mouse models including xenografts and syngeneic models to determine its effect on tumor immune response.
  • Transglutaminase 2 maintains hepatocyte growth factor signaling to enhance the epidermal cancer cell phenotype

    Chen, Xi; Adhikary, Gautam; Shrestha, Suruchi; Xu, Wen; Keillor, Jeffrey W.; Naselsky, Warren; Eckert, Richard (Richard L.) (2022-06-09)
  • Molecular Characterization of Progressive Fibrosis in the Liver by Single-Nuclei RNA Sequencing

    Rousselle, Thomas; McDaniels, Jennifer; Shetty, A.; Bardhi, Elissa; Polsky, D.; Williams, E.; Maluf, Daniel; Mas, Valeria (2022-06)

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