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Synthesis, Structure-Activity Relationships, And Antitumor Activities Of Quinoxiline-Containing Inhibitors Of The Protein-Protein Interactions Between Transcription Coactivator Af9/Enl And Dot1l/Af4, Chandra Bhushan Mishra, Xin Li, Bala Krishna Moku, Sehun Kwak, Dnyaneshwar N Garad, Yongcheng Song

Faculty, Staff and Students Publications

Mixed lineage leukemia (MLL) gene rearrangements cause ~75% of acute leukemia in infants and 5-10% in children and adults with poor clinical outcomes. Protein-protein interactions (PPI) between frequent MLL fusion partners AF9/ENL and AF4 or histone methyltransferase DOT1L are drug targets for MLL-rearranged (MLL-r) leukemia. Sixty-seven quinoxiline compounds were synthesized and tested for their ability to inhibit such PPIs. Compounds 16, 17, 59 and 63 were found to be potent inhibitors with IC50 values of 0.35-1.5 μM. Structure-activity relationships are discussed. Potent inhibitors can suppress expression of MLL target genes Myc and Meis1 and selectively block proliferation of MLL-r and …

Enhanced Ctla-4 Blockade Anti-Tumor Immunity With Apg-157 Combination In A Murine Head And Neck Cancer, Daniel Sanghoon Shin, Saroj Basak, Mysore S Veena, Begoña Comin-Anduix, Arjun Bhattacharya, Tien S Dong, Albert Ko, Philip Han, Jonathan Jacobs, Neda A Moatamed, Luis Avila, Matteo Pellegrini, Marilene Wang, Eri S Srivatsan

Faculty, Staff and Student Publications

BACKGROUND: A phase I clinical study for patients with locally advanced H&N cancer with a new class of botanical drug APG-157 provided hints of potential synergy with immunotherapy. We sought to evaluate the efficacy of the combination of APG-157 and immune checkpoint inhibitors.

METHODS: CCL23, UM-SCC1 (human), and SCCVII (HPV-), MEER (HPV+) (murine) H&N cancer cell lines were utilized for in vitro and in vivo studies. We measured tumor growth by treating the mice with APG-157, anti-PD-1, and anti-CTLA-4 antibody combinations (8 groups). The tumor microenvironments were assessed by multi-color flow cytometry, immunohistochemistry, and RNA-seq analysis. Fecal microbiome was analyzed …

Recurrent Lymphoid And Myeloid Relapses Due To Treatment Cessations Reveal Natural History Of Ph-Positive B-All And Pose A Diagnostic Challenge, Shimin Hu, Elias J Jabbour, Collin Y Hu, Guilin Tang, Wei Wang, L Jeffrey Medeiros, Carlos Bueso-Ramos

Faculty, Staff and Student Publications

No abstract provided.

Slo3 In The Fast Lane: The Latest Male Contraceptive Target With A Promising Small-Molecule Inhibitor, Zhi Tan, Thomas X Garcia

Faculty, Staff and Students Publications

No abstract provided.

Structure-Activity Relationship And Antitumor Activity Of 1,4-Pyrazine-Containing Inhibitors Of Histone Acetyltransferases P300/Cbp, Shenyou Nie, Fangrui Wu, Jingyu Wu, Xin Li, Chao Zhou, Yuan Yao, Yongcheng Song

Faculty, Staff and Students Publications

Acetylation of histone lysine residues by histone acetyltransferase (HAT) p300 and its paralog CBP play important roles in gene regulation in health and diseases. The HAT domain of p300/CBP has been found to be a potential drug target for cancer. Compound screening followed by structure-activity relationship studies yielded a novel series of 1,4-pyrazine-containing inhibitors of p300/CBP HAT with their IC50s as low as 1.4 μM. Enzyme kinetics and other studies support the most potent compound 29 is a competitive inhibitor of p300 HAT against the substrate histone. It exhibited a high selectivity for p300 and CBP, with negligible activity on …

Thioredoxin Reductase Is A Major Regulator Of Metabolism In Leukemia Cells, Sheelarani Karunanithi, Ruifu Liu, Yongchun Hou, Giancarlo Gonzalez, Natasha Oldford, Anne Jessica Roe, Nethrie Idipilly, Kalpana Gupta, Chandra Sekhar Amara, Satwikreddy Putluri, Grace Kyueun Lee, Juan Valentin-Goyco, Lindsay Stetson, Stephen A Moreton, Vasanta Putluri, Shyam M Kavuri, Yogen Saunthararajah, Marcos De Lima, Gregory P Tochtrop, Nagireddy Putluri, David N Wald

Faculty, Staff and Students Publications

Despite the fact that AML is the most common acute leukemia in adults, patient outcomes are poor necessitating the development of novel therapies. We identified that inhibition of Thioredoxin Reductase (TrxR) is a promising strategy for AML and report a highly potent and specific inhibitor of TrxR, S-250. Both pharmacologic and genetic inhibition of TrxR impairs the growth of human AML in mouse models. We found that TrxR inhibition leads to a rapid and marked impairment of metabolism in leukemic cells subsequently leading to cell death. TrxR was found to be a major and direct regulator of metabolism in AML …

Structure, Function And Inhibition Of Critical Protein-Protein Interactions Involving Mixed Lineage Leukemia 1 And Its Fusion Oncoproteins, Xin Li, Yongcheng Song

Faculty, Staff and Students Publications

Mixed lineage leukemia 1 (MLL1, also known as MLL or KMT2A) is an important transcription factor and histone-H3 lysine-4 (H3K4) methyltransferase. It is a master regulator for transcription of important genes (e.g., Hox genes) for embryonic development and hematopoiesis. However, it is largely dispensable in matured cells. Dysregulation of MLL1 leads to overexpression of certain Hox genes and eventually leukemia initiation. Chromosome translocations involving MLL1 cause ~ 75% of acute leukemia in infants and 5-10% in children and adults with a poor prognosis. Targeted therapeutics against oncogenic fusion MLL1 (onco-MLL1) are therefore needed. Onco-MLL1 consists of the N-terminal DNA-interacting domains …

Synthesis, Structure-Activity Relationships, And Antiviral Activity Of Allosteric Inhibitors Of Flavivirus Ns2b-Ns3 Protease, Shenyou Nie, Yuan Yao, Fangrui Wu, Xiaowei Wu, Jidong Zhao, Yuanda Hua, Jingyu Wu, Tong Huo, Yi-Lun Lin, Alexander R Kneubehl, Megan B Vogt, Josephine Ferreon, Rebecca Rico-Hesse, Yongcheng Song

Faculty, Staff and Students Publications

Flaviviruses, including Zika, dengue and West Nile virus, are important human pathogens. The highly conserved NS2B-NS3 protease of Flavivirus is essential for viral replication and therefore a promising drug target. Through compound screen followed by medicinal chemistry studies, a novel series of 2,5,6-trisubstituted pyrazine compounds are found to be potent, allosteric inhibitors of Zika virus protease (ZVpro) with IC50 values as low as 130 nM. Their structure-activity relationships are discussed. The ZVpro inhibitors also inhibit homologous proteases of dengue and West Nile virus and their inhibitory activities are correlated. The most potent compounds 47 and 103 potently inhibited Zika virus …

Follicular Lymphoma Tregs Have A Distinct Transcription Profile Impacting Their Migration And Retention In The Malignant Lymph Node, Hristina Nedelkovska, Alexander F. Rosenberg, Shannon P. Hilchey, Ollivier Hyrien, W. Richard Burack, Sally A. Quataert, Christina M. Baker, Mitra Azadniv, Stephen L. Welle, Stephen M. Ansell, Minsoo Kim, Steven H. Bernstein

Biology

We have previously shown that regulatory T cells (Tregs) infiltrating follicular lymphoma lymph nodes are quantitatively and qualitatively different than those infiltrating normal and reactive nodes. To gain insight into how such Treg populations differ, we performed RNA sequence (RNAseq) analyses on flow sorted Tregs from all three sources. We identify several molecules that could contribute to the observed increased suppressive capacity of follicular lymphoma nodal tregs, including upregulation of CTLA-4, IL-10, and GITR, all confirmed by protein expression. In addition, we identify, and confirm functionally, a novel mechanism by which Tregs target to and accumulate within a human tumor …

Neuroinflammation And Neurologic Deficits In Diabetes Linked To Brain Accumulation Of Amylin, Sarah Srodulski, Savita Sharma, Adam B. Bachstetter, Jennifer M. Brelsfoard, Conrado Pascual, Xinmin Simon Xie, Kathryn E. Saatman, Linda J. Van Eldik, Florin Despa

Pharmacology and Nutritional Sciences Faculty Publications

BACKGROUND: We recently found that brain tissue from patients with type-2 diabetes (T2D) and cognitive impairment contains deposits of amylin, an amyloidogenic hormone synthesized and co-secreted with insulin by pancreatic β-cells. Amylin deposition is promoted by chronic hypersecretion of amylin (hyperamylinemia), which is common in humans with obesity or pre-diabetic insulin resistance. Human amylin oligomerizes quickly when oversecreted, which is toxic, induces inflammation in pancreatic islets and contributes to the development of T2D. Here, we tested the hypothesis that accumulation of oligomerized amylin affects brain function.

METHODS: In contrast to amylin from humans, rodent amylin is neither amyloidogenic nor cytotoxic. …

Muc4 And Muc5ac Are Highly Specific Tumour-Associated Mucins In Biliary Tract Cancer., W. R. Matull, F. Andreola, A. Loh, Z. Adiguzel, M. Deheragoda, U. Qureshi, Surinder K. Batra, D. M. Swallow, S. P. Pereira

Journal Articles: Biochemistry & Molecular Biology

Alterations in epithelial mucin expression are associated with carcinogenesis, but there are few data in biliary tract cancer (BTC). In pancreatic malignancy, MUC4 is a diagnostic and prognostic tumour marker, whereas MUC5AC has been proposed as a sensitive serological marker for BTC. We assessed MUC4 and MUC5AC expression in (i) prospectively collected bile and serum specimens from 72 patients with biliary obstruction (39 BTC) by real-time reverse transcriptase-PCR (qPCR) and western blot analysis, and (ii) 79 archived biliary tissues (69 BTC) by immunohistochemistry. In bile, MUC4 protein was detected in 27% of BTC and 29% of primary sclerosing cholangitis (PSC) …