Digital Commons Network^™

3pnmf-Mkl: A Non-Negative Matrix Factorization-Based Multiple Kernel Learning Method For Multi-Modal Data Integration And Its Application To Gene Signature Detection\, Saurav Mallik, Anasua Sarkar, Sagnik Nath, Ujjwal Maulik, Supantha Das, Soumen Kumar Pati, Soumadip Ghosh, Zhongming Zhao

Faculty, Staff and Student Publications

In this current era, biomedical big data handling is a challenging task. Interestingly, the integration of multi-modal data, followed by significant feature mining (gene signature detection), becomes a daunting task. Remembering this, here, we proposed a novel framework, namely, three-factor penalized, non-negative matrix factorization-based multiple kernel learning with soft margin hinge loss (3PNMF-MKL) for multi-modal data integration, followed by gene signature detection. In brief, limma, employing the empirical Bayes statistics, was initially applied to each individual molecular profile, and the statistically significant features were extracted, which was followed by the three-factor penalized non-negative matrix factorization method used for data/matrix fusion …

Ex Vivo Drug Sensitivity Correlates With Clinical Response And Supports Personalized Therapy In Pediatric Aml, Debbie C Strachan, Christine J Gu, Ryosuke Kita, Erica K Anderson, Michelle A Richardson, George Yam, Graham Pimm, Jordan Roselli, Alyssa Schweickert, Maci Terrell, Raushan Rashid, Alan K Gonzalez, Hailey H Oviedo, Michelle C Alozie, Tamilini Ilangovan, Andrea N Marcogliese, Hiroomi Tada, Marianne T Santaguida, Alexandra M Stevens

Faculty, Staff and Students Publications

Acute myeloid leukemia (AML) is a heterogeneous disease that accounts for ~20% of all childhood leukemias, and more than 40% of children with AML relapse within three years of diagnosis. Although recent efforts have focused on developing a precise medicine-based approach towards treating AML in adults, there remains a critical gap in therapies designed specifically for children. Here, we present ex vivo drug sensitivity profiles for children with de novo AML using an automated flow cytometry platform. Fresh diagnostic blood or bone marrow aspirate samples were screened for sensitivity in response to 78 dose conditions by measuring the reduction in …

Isolation, Culture, And Immunophenotypic Analysis Of Bone Marrow Hspcs From Patients With Myelodysplastic Syndromes, Irene Ganan-Gomez, Karen Clise-Dwyer, Simona Colla

Faculty, Staff and Student Publications

Drug testing assays in hematopoietic stem and progenitor cells (HSPCs) are fundamental in biological studies of myelodysplastic syndromes (MDS) but have historically entailed a technical challenge. This protocol allows the efficient isolation of MDS HSPCs from bone marrow mononuclear cell fractions and their culturing with the support of stromal cells for improved maintenance during drug testing. Lastly, specific steps are given to quantify surviving cells and assess changes in the HSPC hierarchies.

For complete details on the use and execution of this protocol, please refer to Ganan-Gomez et al. (2022).

Structural Variants Drive Context-Dependent Oncogene Activation In Cancer, Zhichao Xu, Dong-Sung Lee, Sahaana Chandran, Victoria T Le, Rosalind Bump, Jean Yasis, Sofia Dallarda, Samantha Marcotte, Benjamin Clock, Nicholas Haghani, Chae Yun Cho, Kadir C Akdemir, Selene Tyndale, P Andrew Futreal, Graham Mcvicker, Geoffrey M Wahl, Jesse R Dixon

Faculty, Staff and Student Publications

Higher-order chromatin structure is important for the regulation of genes by distal regulatory sequences. Structural variants (SVs) that alter three-dimensional (3D) genome organization can lead to enhancer-promoter rewiring and human disease, particularly in the context of cancer3. However, only a small minority of SVs are associated with altered gene expression4,5, and it remains unclear why certain SVs lead to changes in distal gene expression and others do not. To address these questions, we used a combination of genomic profiling and genome engineering to identify sites of recurrent changes in 3D genome structure in cancer and determine the effects of specific …

Notch Missense Mutations In Drosophila Reveal Functions Of Specific Egf-Like Repeats In Notch Folding, Trafficking, And Signaling, Hilman Nurmahdi, Mao Hasegawa, Elzava Yuslimatin Mujizah, Takeshi Sasamura, Mikiko Inaki, Shinya Yamamoto, Tomoko Yamakawa, Kenji Matsuno

Duncan NRI Faculty and Staff Publications

Notch signaling plays various roles in cell-fate specification through direct cell–cell interactions. Notch receptors are evolutionarily conserved transmembrane proteins with multiple epidermal growth factor (EGF)-like repeats. Drosophila Notch has 36 EGF-like repeats, and while some play a role in Notch signaling, the specific functions of most remain unclear. To investigate the role of each EGF-like repeat, we used 19 previously identified missense mutations of Notch with unique amino acid substitutions in various EGF-like repeats and a transmembrane domain; 17 of these were identified through a single genetic screen. We assessed these mutants’ phenotypes in the nervous system and hindgut during …

Bone Marrow Endothelial Cells Increase Prostate Cancer Cell Apoptosis In 3d Triculture Model Of Reactive Stroma, Lindsey K Sablatura, Tristen V Tellman, Aemin Kim, Mary C Farach-Carson

Faculty, Staff and Student Publications

The bone marrow tumor microenvironment (BMTE) is a complex network of cells, extracellular matrix, and sequestered signaling factors that initially act as a hostile environment for disseminating tumor cells (DTCs) from the cancerous prostate. Three-dimensional (3D) culture systems offer an opportunity to better model these complex interactions in reactive stroma, providing contextual behaviors for cancer cells, stromal cells, and endothelial cells. Using a new system designed for the triculture of osteoblastic prostate cancer (PCa) cells, stromal cells, and microvascular endothelial cells, we uncovered a context-specific pro-apoptotic effect of endothelial cells of the bone marrow different from those derived from the …

An Auto-Inhibited State Of Protein Kinase G And Implications For Selective Activation, Rajesh Sharma, Jeong Joo Kim, Liying Qin, Philipp Henning, Madoka Akimoto, Bryan Vanschouwen, Gundeep Kaur, Banumathi Sankaran, Kevin R Mackenzie, Giuseppe Melacini, Darren E Casteel, Friedrich W Herberg, Choel Kim

Faculty, Staff and Students Publications

Cyclic GMP-dependent protein kinases (PKGs) are key mediators of the nitric oxide/cyclic guanosine monophosphate (cGMP) signaling pathway that regulates biological functions as diverse as smooth muscle contraction, cardiac function, and axon guidance. Understanding how cGMP differentially triggers mammalian PKG isoforms could lead to new therapeutics that inhibit or activate PKGs, complementing drugs that target nitric oxide synthases and cyclic nucleotide phosphodiesterases in this signaling axis. Alternate splicing of PRKG1 transcripts confers distinct leucine zippers, linkers, and auto-inhibitory (AI) pseudo-substrate sequences to PKG Iα and Iβ that result in isoform-specific activation properties, but the mechanism of enzyme auto-inhibition and its alleviation …

Genomewide Crispr/Cas9 Screen Identifies Network Of Protein Complexes That Regulate Trim24, Lalit Patel

Dissertations and Theses (Open Access)

TRIM24 is an oncogenic chromatin reader that is frequently overexpressed in human tumors and associated with poor prognosis. However, TRIM24 is rarely mutated, duplicated, or rearranged in cancer. This raises questions about how TRIM24 is regulated and whether changes in its regulation are responsible for its activity in cancer.

To investigate this possibility, I performed a genomewide CRISPR/Cas9 screen library using fluorescence activated cell sorting (FACS) to identify regulators of TRIM24. The screen was enabled by two innovations. I engineered cells with an in-frame knock-in of mClover3 to the endogenous copy of TRIM24 to allow fluorescent monitoring of TRIM24 expression …

Cell Plasticity In Regeneration In The Stomach And Beyond, Mahliyah Adkins-Threats, Jason C Mills

Faculty, Staff and Students Publications

Recent studies using cell lineage-tracing techniques, organoids, and single-cell RNA sequencing analyses have revealed: 1) adult organs use cell plasticity programs to recruit progenitor cells to regenerate tissues after injury, and 2) plasticity is far more common than previously thought, even in homeostasis. Here, we focus on the complex interplay of normal stem cell differentiation and plasticity in homeostasis and after injury, using the gastric epithelium as a touchstone. We also examine common features of regenerative programs and discuss the evolutionarily conserved, stepwise process of paligenosis which reprograms mature cells into progenitors that can repair damaged tissue. Finally, we discuss …

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 …

Reshaping The Tumor Microenvironment With Oncolytic Viruses, Positive Regulation Of The Immune Synapse, And Blockade Of The Immunosuppressive Oncometabolic Circuitry, Teresa T Nguyen, Dong Ho Shin, Sagar Sohoni, Sanjay K Singh, Yisel Rivera-Molina, Hong Jiang, Xuejun Fan, Joy Gumin, Frederick F Lang, Christopher Alvarez-Breckenridge, Filipa Godoy-Vitorino, Lisha Zhu, W Jim Zheng, Lijie Zhai, Erik Ladomersky, Kristen L Lauing, Marta M Alonso, Derek A Wainwright, Candelaria Gomez-Manzano, Juan Fueyo

Faculty, Staff and Student Publications

Background: Oncolytic viruses are considered part of immunotherapy and have shown promise in preclinical experiments and clinical trials. Results from these studies have suggested that tumor microenvironment remodeling is required to achieve an effective response in solid tumors. Here, we assess the extent to which targeting specific mechanisms underlying the immunosuppressive tumor microenvironment optimizes viroimmunotherapy.

Methods: We used RNA-seq analyses to analyze the transcriptome, and validated the results using Q-PCR, flow cytometry, and immunofluorescence. Viral activity was analyzed by replication assays and viral titration. Kyn and Trp metabolite levels were quantified using liquid chromatography-mass spectrometry. Aryl hydrocarbon receptor (AhR) activation …

Gain-Of-Signal Assays For Probing Inhibition Of Sars-Cov-2 Mpro/3clpro In Living Cells, Seyed Arad Moghadasi, Morgan A Esler, Yuka Otsuka, Jordan T Becker, Sofia N Moraes, Constance B Anderson, Srinivas Chamakuri, Christopher Belica, Chloe Wick, Daniel A Harki, Damian W Young, Louis Scampavia, Timothy P Spicer, Ke Shi, Hideki Aihara, William L Brown, Reuben S Harris

Faculty, Staff and Students Publications

The main protease, Mpro, of SARS-CoV-2 is required to cleave the viral polyprotein into precise functional units for virus replication and pathogenesis. Here, we report quantitative reporters for Mpro function in living cells in which protease inhibition by genetic or chemical methods results in robust signal readouts by fluorescence (enhanced green fluorescent protein [eGFP]) or bioluminescence (firefly luciferase). These gain-of-signal systems are scalable to high-throughput platforms for quantitative discrimination between Mpro mutants and/or inhibitor potencies as evidenced by validation of several reported inhibitors. Additional utility is shown by single Mpro amino acid variants and structural information combining to demonstrate that …

Chemotherapy Coupled To Macrophage Inhibition Induces T-Cell And B-Cell Infiltration And Durable Regression In Triple-Negative Breast Cancer, Swarnima Singh, Nigel Lee, Diego A Pedroza, Igor L Bado, Clark Hamor, Licheng Zhang, Sergio Aguirre, Jingyuan Hu, Yichao Shen, Yitian Xu, Yang Gao, Na Zhao, Shu-Hsia Chen, Ying-Wooi Wan, Zhandong Liu, Jeffrey T Chang, Daniel Hollern, Charles M Perou, Xiang H F Zhang, Jeffrey M Rosen

Duncan NRI Faculty and Staff Publications

Immunosuppressive elements within the tumor microenvironment, such as tumor-associated macrophages (TAM), can present a barrier to successful anti-tumor responses by cytolytic T cells. Here we employed preclinical syngeneic p53 null mouse models of triple-negative breast cancer (TNBC) to develop a treatment regimen that harnessed the immunostimulatory effects of low-dose cyclophosphamide coupled with the pharmacologic inhibition of TAMs using either a small molecule CSF1R inhibitor or an anti-CSF1R antibody. This therapeutic combination was effective in treating several highly aggressive TNBC murine mammary tumor and lung metastasis models. Single cell RNA sequencing characterized tumor-infiltrating lymphocytes (TIL) including helper T cells and antigen-presenting …

Targeting A Chemo-Induced Adaptive Signaling Circuit Confers Therapeutic Vulnerabilities In Pancreatic Cancer, Xu Feng, Mengfan Tang, Merve Dede, Dan Su, Guangsheng Pei, Dadi Jiang, Chao Wang, Zhen Chen, Mi Li, Litong Nie, Yun Xiong, Siting Li, Jeong-Min Park, Huimin Zhang, Min Huang, Klaudia Szymonowicz, Zhongming Zhao, Traver Hart, Junjie Chen

Faculty, Staff and Student Publications

Exploiting cancer vulnerabilities is critical for the discovery of anticancer drugs. However, tumor suppressors cannot be directly targeted because of their loss of function. To uncover specific vulnerabilities for cells with deficiency in any given tumor suppressor(s), we performed genome-scale CRISPR loss-of-function screens using a panel of isogenic knockout cells we generated for 12 common tumor suppressors. Here, we provide a comprehensive and comparative dataset for genetic interactions between the whole-genome protein-coding genes and a panel of tumor suppressor genes, which allows us to uncover known and new high-confidence synthetic lethal interactions. Mining this dataset, we uncover essential paralog gene …

Exploiting Chemogenetic And Genetic Interactions In Human Cells As An Avenue For New Therapeutic Opportunities, Medina Colic

Dissertations and Theses (Open Access)

The advent of CRISPR technology and its adaptation to the mammalian genome made whole-genome knockout screens possible directly in human cells. Gene knockout answers how essential that gene is for cell fitness and proliferation. Genes showing moderate to severe fitness defects are called essential genes and provide insights into disease-specific candidate therapeutic targets. Additionally, CRISPR offers other applications for genome editing. Two applications this dissertation is based on are 1) combination of gene knockout and drug treatment, which enables the identification of chemogenetic interactions, or gene mutations that enhance or suppress the activity of a drug, and 2) combinatorial editing, …

Cngpld: Case-Control Copy-Number Analysis Using Gaussian Process Latent Difference, David J H Shih, Ruoxing Li, Peter Müller, W Jim Zheng, Kim-Anh Do, Shiaw-Yih Lin, Scott L Carter

Faculty, Staff and Student Publications

MOTIVATION: Cross-sectional analyses of primary cancer genomes have identified regions of recurrent somatic copy-number alteration, many of which result from positive selection during cancer formation and contain driver genes. However, no effective approach exists for identifying genomic loci under significantly different degrees of selection in cancers of different subtypes, anatomic sites or disease stages.

RESULTS: CNGPLD is a new tool for performing case-control somatic copy-number analysis that facilitates the discovery of differentially amplified or deleted copy-number aberrations in a case group of cancer compared with a control group of cancer. This tool uses a Gaussian process statistical framework in order …

Retinal Organoids Derived From Rhesus Macaque Ipscs Undergo Accelerated Differentiation Compared To Human Stem Cells, Antonio Jacobo Lopez, Sangbae Kim, Xinye Qian, Jeffrey Rogers, J Timothy Stout, Sara M Thomasy, Anna La Torre, Rui Chen, Ala Moshiri

Faculty, Staff and Students Publications

PURPOSE: To compare the timing and efficiency of the development of Macaca mulatta, a nonhuman primate (NHP), induced pluripotent stem cell (rhiPSC) derived retinal organoids to those derived from human embryonic stem cells (hESCs).

RESULTS: Generation of retinal organoids was achieved from both human and several NHP pluripotent stem cell lines. All rhiPSC lines resulted in retinal differentiation with the formation of optic vesicle-like structures similar to what has been observed in hESC retinal organoids. NHP retinal organoids had laminated structure and were composed of mature retinal cell types including cone and rod photoreceptors. Single-cell RNA sequencing was conducted at …

Effects Of Placebo Administration On Immune Mechanisms And Relationships With Central Endogenous Opioid Neurotransmission, Alan Prossin, Alisa Koch, Phillip Campbell, Geoffroy Laumet, Christian S Stohler, Robert Dantzer, Jon-Kar Zubieta

Faculty, Staff and Student Publications

Behavioral conditioning and expectation can have profound impact on animal and human physiology. Placebo, administered under positive expectation in clinical trials, can have potent effects on disease pathology, obscuring active medications. Emerging evidence suggests placebo-responsive neurotransmitter systems (e.g., endogenous opioid) regulate immune function by manipulating inflammatory proteins including IL-18, a potent pro-inflammatory, nociceptive cytokine implicated in pathophysiology of various diseases. Validation that neuroimmune interactions involving brain μ-opioid receptor (MOR) activity and plasma IL-18 underlie placebo analgesic expectation could have widespread clinical applications. Unfortunately, current lack of mechanistic clarity obfuscates clinical translation. To elucidate neuroimmune interactions underlying placebo analgesia, we exposed …

Prefrontal Glutamate Neurotransmission In Ptsd: A Novel Approach To Estimate Synaptic Strength In Vivo In Humans, Lynnette A Averill, Lihong Jiang, Prerana Purohit, Anastasia Coppoli, Christopher L Averill, Jeremy Roscoe, Benjamin Kelmendi, Henk M De Feyter, Robin A De Graaf, Ralitza Gueorguieva, Gerard Sanacora, John H Krystal, Douglas L Rothman, Graeme F Mason, Chadi G Abdallah

Staff and Researcher Publications

Background: Trauma and chronic stress are believed to induce and exacerbate psychopathology by disrupting glutamate synaptic strength. However, in vivo in human methods to estimate synaptic strength are limited. In this study, we established a novel putative biomarker of glutamatergic synaptic strength, termed energy-per-cycle (EPC). Then, we used EPC to investigate the role of prefrontal neurotransmission in trauma-related psychopathology.

Methods: Healthy controls (n = 18) and patients with posttraumatic stress (PTSD; n = 16) completed 13C-acetate magnetic resonance spectroscopy (MRS) scans to estimate prefrontal EPC, which is the ratio of neuronal energetic needs per glutamate neurotransmission cycle (VTCA/VCycle).

Results: Patients …

Comparative Analysis Of Gene Expression Patterns For Oral Epithelial Cell Functions In Periodontitis, Octavio A Gonzalez, Sreenatha Kirakodu, Linh M Nguyen, Luis Orraca, Michael J Novak, Janis Gonzalez-Martinez, Jeffrey L Ebersole

Faculty, Staff and Student Publications

The structure and function of epithelial cells are critical for the construction and maintenance of intact epithelial surfaces throughout the body. Beyond the mechanical barrier functions, epithelial cells have been identified as active participants in providing warning signals to the host immune and inflammatory cells and in communicating various detailed information on the noxious challenge to help drive specificity in the characteristics of the host response related to health or pathologic inflammation. Rhesus monkeys were used in these studies to evaluate the gingival transcriptome for naturally occurring disease samples (GeneChip® Rhesus Macaque Genome Array) or for ligature-induced disease (GeneChip® Rhesus …

Morphological Description Of Laevicaulisstuhlmanni (Simroth, 1895) (Pulmonata, Veronicellidae) From Egypt, Reham Fathey Ali, David G Robinson, Fabio Liberto

Faculty, Staff and Student Publications

BACKGROUND: Terrestrial slugs and snails are increasingly becoming serious pests of agricultural, horticultural and ornamental plants in Egypt, resulting in major economic losses.

NEW INFORMATION: This paper provides a detailed morphological and anatomical description of the veronicellid slug Laevicaulisstuhlmanni (Simroth, 1895) that has been recently recorded from Egypt. This population from Egypt is compared with Laevicaulis populations recently reported and described from Libya as L.striatus (Simroth, 1896) and with available data in literature. Some notes and a distribution map of the veronicellids introduced in north-eastern Africa are provided.

Dissecting The Mechanisms Of Venetoclax Resistance In Myelodysplastic Syndromes, Shuaitong Chen

Dissertations and Theses (Open Access)

Myelodysplastic syndromes (MDS) are a class of heterogeneous clonal hematopoietic disorders. The current standard of care for MDS is the hypomethylating agent (HMA)-based therapy. However, only 50 percent of the patients respond, with transient effects and no approved second-line treatment options after their diseases progress to acute myeloid leukemia (AML). The mechanisms that govern HMA failure are unknown. Recently, we unveiled that MDS are maintained and propagated by two different immunophenotypically distinct hierarchical cellular organizations of MDS hematopoietic stem and progenitor cells (HSPCs) through the upregulation of specific survival pathways. This finding allowed us to potentially stratify MDS patients into …

Esomeprazole Attenuates Inflammatory And Fibrotic Response In Lung Cells Through The Mapk/Nrf2/Ho1 Pathway, Afshin Ebrahimpour, Min Wang, Li Li, Anil G Jegga, Mark D Bonnen, N Tony Eissa, Ganesh Raghu, Soma Jyothula, Farrah Kheradmand, Nicola A Hanania, Ivan O Rosas, Yohannes T Ghebre

Faculty, Staff and Students Publications

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is an orphan disease characterized by progressive loss of lung function resulting in shortness of breath and often death within 3-4 years of diagnosis. Repetitive lung injury in susceptible individuals is believed to promote chronic oxidative stress, inflammation, and uncontrolled collagen deposition. Several preclinical and retrospective clinical studies in IPF have reported beneficial outcomes associated with the use of proton pump inhibitors (PPIs) such as esomeprazole. Accordingly, we sought to investigate molecular mechanism(s) by which PPIs favorably regulate the disease process.

METHODS: We stimulated oxidative stress, pro-inflammatory and profibrotic phenotypes in primary human lung epithelial …

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 …

Discovery And Characterization Of Bromodomain 2-Specific Inhibitors Of Brdt, Zhifeng Yu, Angela F Ku, Justin L Anglin, Rajesh Sharma, Melek Nihan Ucisik, John C Faver, Feng Li, Pranavanand Nyshadham, Nicholas Simmons, Kiran L Sharma, Sureshbabu Nagarajan, Kevin Riehle, Gundeep Kaur, Banumathi Sankaran, Marta Storl-Desmond, Stephen S Palmer, Damian W Young, Choel Kim, Martin M Matzuk

Faculty, Staff and Students Publications

Bromodomain testis (BRDT), a member of the bromodomain and extraterminal (BET) subfamily that includes the cancer targets BRD2, BRD3, and BRD4, is a validated contraceptive target. All BET subfamily members have two tandem bromodomains (BD1 and BD2). Knockout mice lacking BRDT-BD1 or both bromodomains are infertile. Treatment of mice with JQ1, a BET BD1/BD2 nonselective inhibitor with the highest affinity for BRD4, disrupts spermatogenesis and reduces sperm number and motility. To assess the contribution of each BRDT bromodomain, we screened our collection of DNA-encoded chemical libraries for BRDT-BD1 and BRDT-BD2 binders. High-enrichment hits were identified and resynthesized off-DNA and examined …

Inhibition Of Camkk2 Impairs Autophagy And Castration-Resistant Prostate Cancer Via Suppression Of Ampk-Ulk1 Signaling, Chenchu Lin, Alicia M Blessing, Thomas L Pulliam, Yan Shi, Sandi R Wilkenfeld, Jenny J Han, Mollianne M Murray, Alexander H Pham, Kevin Duong, Sonja N Brun, Reuben J Shaw, Michael M Ittmann, Daniel E Frigo

Faculty, Staff and Students Publications

Previous work has suggested androgen receptor (AR) signaling mediates prostate cancer progression in part through the modulation of autophagy. However, clinical trials testing autophagy inhibition using chloroquine derivatives in men with castration-resistant prostate cancer (CRPC) have yet to yield promising results, potentially due to the side effects of this class of compounds. We hypothesized that identification of the upstream activators of autophagy in prostate cancer could highlight alternative, context-dependent targets for blocking this important cellular process during disease progression. Here, we used molecular, genetic and pharmacological approaches to elucidate an AR-mediated autophagy cascade involving Ca2+/calmodulin-dependent protein kinase kinase 2 (CAMKK2; …

Tools For Visualizing And Analyzing Fourier Space Sampling In Cryo-Em, Philip R Baldwin, Dmitry Lyumkis

Faculty, Staff and Students Publications

A complete understanding of how an orientation distribution contributes to a cryo-EM reconstruction remains lacking. It is necessary to begin critically assessing the set of views to gain an understanding of its effect on experimental reconstructions. Toward that end, we recently suggested that the type of orientation distribution may alter resolution measures in a systematic manner. We introduced the sampling compensation factor (SCF), which incorporates how the collection geometry might change the spectral signal-to-noise ratio (SSNR), irrespective of the other experimental aspects. We show here that knowledge of the sampling restricted to spherical surfaces of sufficiently large radii in Fourier …

Rapid Induction Of The Unfolded Protein Response And Apoptosis By Estrogen Mimic Ttc-352 For The Treatment Of Endocrine-Resistant Breast Cancer, Balkees Abderrahman, Philipp Y Maximov, Ramona F Curpan, Sean W Fanning, Jay S Hanspal, Ping Fan, Charles E Foulds, Yue Chen, Anna Malovannaya, Antrix Jain, Rui Xiong, Geoffrey L Greene, Debra A Tonetti, Gregory R J Thatcher, V Craig Jordan

Faculty, Staff and Students Publications

Patients with long-term estrogen-deprived breast cancer (BC), after resistance to tamoxifen or aromatase inhibitors develops, can experience tumor regression when treated with estrogens. Estrogen’s anti-tumor effect is attributed to apoptosis via the estrogen receptor (ER). Estrogen treatment can have unpleasant gynecological and non-gynecological adverse events thus the development of safer estrogenic agents remains a clinical priority. Here, we study synthetic selective estrogen mimics (SEMs) BMI-135 and TTC-352, and the naturally-occurring estrogen estetrol (E4), which are proposed as safer estrogenic agents compared to 17β-estradiol (E2), for the treatment of endocrine-resistant BC. TTC-352 and E4 are being evaluated in BC clinical trials. …

Small-Molecule Inhibitor Of Af9/Enl-Dot1l/Af4/Aff4 Interactions Suppresses Malignant Gene Expression And Tumor Grow, Fangrui Wu, Shenyou Nie, Yuan Yao, Tong Huo, Xin Li, Xiaowei Wu, Jidong Zhao, Yi-Lun Lin, Yinjie Zhang, Qianxing Mo, Yongcheng Song

Faculty, Staff and Students Publications

Chromosome translocations involving mixed lineage leukemia (MLL) gene cause acute leukemia with a poor prognosis. MLL is frequently fused with transcription cofactors AF4 (~35%), AF9 (25%) or its paralog ENL (10%). The AHD domain of AF9/ENL binds to AF4, its paralog AFF4, or histone-H3 lysine-79 (H3K79) methyltransferase DOT1L. Formation of AF9/ENL/AF4/AFF4-containing super elongation complexes (SEC) and the catalytic activity of DOT1L are essential for MLL-rearranged leukemia. Protein-protein interactions (PPI) between AF9/ENL and DOT1L/AF4/AFF4 are therefore a potential drug target.

Methods: Compound screening followed by medicinal chemistry was used to find inhibitors of such PPIs, which were examined for their biological …

Development Of Computational To Ols To Target Microrna, Luo Song

Dissertations and Theses (Open Access)

MicroRNAs (a.k.a, miRNAs) play an important role in disease development. However, few of their structures have been determined and structure-based computational methods remain challenging in accurately predicting their interactions with small molecules. To address this issue, my thesis is to develop integrated approaches to screening for novel inhibitors by targeting specific structure motifs in miRNAs. The project starts with implementing a tool to find potential miRNA targets with desired motifs. I combined both sequence information of miRNAs and known RNA structure data from Protein Data Bank (PDB) to predict the miRNA structure and identify the motif to target, then I …