Biochemistry, Biophysics, and Structural Biology Commons^™

Human Schwann Cells In Vitro I. Nerve Tissue Processing, Pre-Degeneration, Isolation, And Culturing Of Primary Cells, Gabriela I. Aparicio, Paula V. Monje

Markey Cancer Center Faculty Publications

This paper presents versatile protocols to prepare primary human Schwann cell (hSC) cultures from mature peripheral nervous system tissues, including fascicles from long spinal nerves, nerve roots, and ganglia. This protocol starts with a description of nerve tissue procurement, handling, and dissection to obtain tissue sections suitable for hSC isolation and culturing. A description follows on how to disintegrate the nerve tissue by delayed enzymatic dissociation, plate the initial cell suspensions on a two-dimensional substrate, and culture the primary hSCs. Each section contains detailed procedures, technical notes, and background information to aid investigators in understanding and managing all steps. Some …

Phosphorylation Of Ahr By Plk1 Promotes Metastasis Of Luad Via Dio2-Th Signaling, Chaohao Li, Derek B. Allison, Daheng He, Fengyi Mao, Xinyi Wang, Piotr G. Rychahou, Ibrahim A. Imam, Yifan Kong, Qiongsi Zhang, Yanquan Zhang, Jinghui Liu, Ruixin Wang, Xiongjian Rao, Sai Wu, B. Mark Evers, Qing Shao, Chi Wang, Zhiguo Li, Xiaoqi Liu

Markey Cancer Center Faculty Publications

Metastasis of lung adenocarcinoma (LUAD) is a major cause of death in patients. Aryl hydrocarbon receptor (AHR), an important transcription factor, is involved in the initiation and progression of lung cancer. Polo-like kinase 1 (PLK1), a serine/threonine kinase, acts as an oncogene promoting the malignancy of multiple cancer types. However, the interaction between these two factors and their significance in lung cancer remain to be determined. In this study, we demonstrate that PLK1 phosphorylates AHR at S489 in LUAD, leading to epithelial-mesenchymal transition (EMT) and metastatic events. RNA-seq analyses reveal that type 2 deiodinase (DIO2) is responsible for EMT and …

Risk-Adjusted Cumulative Sum For Early Detection Of Hospitals With Excess Perioperative Mortality, Vivi W Chen, Alexis P Chidi, Yongquan Dong, Peter A Richardson, David A Axelrod, Laura A Petersen, Nader N Massarweh

Faculty, Staff and Students Publications

IMPORTANCE: National surgical quality improvement programs lack tools for early detection of quality or safety concerns, which risks patient safety because of delayed recognition of poor performance.

OBJECTIVE: To compare the risk-adjusted cumulative sum (CUSUM) with episodic evaluation for early detection of hospitals with excess perioperative mortality.

DESIGN, SETTING, AND PARTICIPANTS: National, observational, hospital-level, comparative effectiveness study of 697 566 patients. Identification of hospitals with excess, risk-adjusted, quarterly 30-day mortality using observed to expected ratios (ie, current criterion standard in the Veterans Affairs Surgical Quality Improvement Program) was compared with the risk-adjusted CUSUM. Patients included in the study underwent a …

Increasing Glutathione Levels By A Novel Posttranslational Mechanism Inhibits Neuronal Hyperexcitability, Ashwini Sri Hari, Rajeswari Banerji, Li-Ping Liang, Ruth E Fulton, Christopher Quoc Huynh, Timothy Fabisiak, Pallavi Bhuyan Mcelroy, James R Roede, Manisha Patel

Faculty, Staff and Students Publications

Glutathione (GSH) depletion, and impaired redox homeostasis have been observed in experimental animal models and patients with epilepsy. Pleiotropic strategies that elevate GSH levels via transcriptional regulation have been shown to significantly decrease oxidative stress and seizure frequency, increase seizure threshold, and rescue certain cognitive deficits. Whether elevation of GSH per se alters neuronal hyperexcitability remains unanswered. We previously showed that thiols such as dimercaprol (DMP) elevate GSH via post-translational activation of glutamate cysteine ligase (GCL), the rate limiting GSH biosynthetic enzyme. Here, we asked if elevation of cellular GSH by DMP altered neuronal hyperexcitability in-vitro and in-vivo. Treatment of …

Endoscopic Vacuum Therapy For Treatment Of Spontaneous And Iatrogenic Upper Gastrointestinal Defects, Kavea Panneerselvam, Jake S Jacob, Ronald E Samuel, Andy Tau, Gyanprakash A Ketwaroo, Wasif M Abidi, Robert J Sealock

Faculty, Staff and Students Publications

BACKGROUND/AIMS: Endoscopic vacuum therapy (EVT) can heal a variety of defects within the gastrointestinal (GI) tract via applying negative pressure, which reduces the defect size, aspirates the infected fluid, and promotes granulation tissue. Here we present our experience with EVT as it relates to both spontaneous and iatrogenic upper GI tract perforations, leaks, and fistulas.

METHODS: This retrospective study was conducted at four large hospital centers. All patients who underwent EVT between June 2018 and March 2021 were included. Data on multiple variables were collected, including demographics, defect size and location, number and intervals of EVT exchanges, technical success, and …

Newer Insights Into Mmtv Replication: The Human Retroviral Proteins Hiv-1 Tat And Htlv-1 Tax Can Transactivate The Mmtv Novel 5’ Element, Thanumol Abdul Khader

Dissertations

The mouse mammary tumor virus (MMTV) is a prototypic betaretrovirus that causes breast cancer in mice. MMTV regulates its gene expression both at the transcriptional and post transcriptional levels. It has hormonally-regulated promoters controlled by negative regulatory factors in a tissue-specific manner. Recently, we identified a novel 24-nucleotide region at the 5' end of the MMTV genome crucial for MMTV gene expression. Its deletion resulted in disruption of MMTV transcript elongation and stability, leading to a complete loss of Gag gene expression. This conserved element is present within the bifurcated stem loop 4, responsible for gRNA dimerization and encapsidation, into …

An Automated Respiratory Data Pipeline For Waveform Characteristic Analysis, Savannah Lusk, Christopher S Ward, Andersen Chang, Avery Twitchell-Heyne, Shaun Fattig, Genevera Allen, Joanna L Jankowsky, Russell S Ray

Faculty, Staff and Students Publications

Comprehensive and accurate analysis of respiratory and metabolic data is crucial to modelling congenital, pathogenic and degenerative diseases converging on autonomic control failure. A lack of tools for high-throughput analysis of respiratory datasets remains a major challenge. We present Breathe Easy, a novel open-source pipeline for processing raw recordings and associated metadata into operative outcomes, publication-worthy graphs and robust statistical analyses including QQ and residual plots for assumption queries and data transformations. This pipeline uses a facile graphical user interface for uploading data files, setting waveform feature thresholds and defining experimental variables. Breathe Easy was validated against manual selection by …

A Small-Molecule Inhibitor Of Topbp1 Exerts Anti-Myc Activity And Synergy With Parp Inhibitors, Fang-Tsyr Lin, Kang Liu, Lidija A Wilhelms Garan, Helena Folly-Kossi, Yongcheng Song, Shwu-Jiuan Lin, Weei-Chin Lin

Faculty, Staff and Students Publications

We have previously identified TopBP1 (topoisomerase IIβ-binding protein 1) as a promising target for cancer therapy, given its role in the convergence of Rb, PI(3)K/Akt, and p53 pathways. Based on this, we conducted a large-scale molecular docking screening to identify a small-molecule inhibitor that specifically targets the BRCT7/8 domains of TopBP1, which we have named 5D4. Our studies show that 5D4 inhibits TopBP1 interactions with E2F1, mutant p53, and Cancerous Inhibitor of Protein Phosphatase 2A. This leads to the activation of E2F1-mediated apoptosis and the inhibition of mutant p53 gain of function. In addition, 5D4 disrupts the interaction of TopBP1 …

Widefield Imaging Of Rapid Pan-Cortical Voltage Dynamics With An Indicator Evolved For One-Photon Microscopy, Xiaoyu Lu, Yunmiao Wang, Zhuohe Liu, Yueyang Gou, Dieter Jaeger, François St-Pierre

Faculty, Staff and Students Publications

Widefield imaging with genetically encoded voltage indicators (GEVIs) is a promising approach for understanding the role of large cortical networks in the neural coding of behavior. However, the limited performance of current GEVIs restricts their deployment for single-trial imaging of rapid neuronal voltage dynamics. Here, we developed a high-throughput platform to screen for GEVIs that combine fast kinetics with high brightness, sensitivity, and photostability under widefield one-photon illumination. Rounds of directed evolution produced JEDI-1P, a green-emitting fluorescent indicator with enhanced performance across all metrics. Next, we optimized a neonatal intracerebroventricular delivery method to achieve cost-effective and wide-spread JEDI-1P expression in …

Opposing Roles For The Α Isoform Of The Catalytic Subunit Of Protein Phosphatase 1 In Inside-Out And Outside-In Integrin Signaling In Murine Platelets, Tanvir Khatlani, Subhashree Pradhan, Kimberly Langlois, Deepika Subramanyam, Rolando E Rumbaut, K Vinod Vijayan

Faculty, Staff and Students Publications

Platelet activation during hemostasis and thrombosis is facilitated by agonist-induced inside–out and integrin αIIbβ3-initiated outside–in signaling via protein kinases and phosphatases. Pharmacological inhibitor studies suggest that the serine/threonine protein phosphatase 1 (PP1) promotes platelet activation. However, since phosphatase inhibitors block all the isoforms of the catalytic subunit of PP1 (PP1c), the role of specific PP1c isoform in platelet signaling remains unclear. Here, we employed a platelet-specific PP1cα−/− mice to explore the contribution of a major PP1 isoform in platelet functions. Loss of PP1cα moderately decreased activation of integrin αIIbβ3, binding of soluble fibrinogen, and aggregation to low-dose thrombin, ADP, and …

Novel Treatments For Pxe: Targeting The Systemic And Local Drivers Of Ectopic Calcification, Ida Joely Jacobs, Qiaoli Li

Department of Biochemistry and Molecular Biology Faculty Papers

Pseudoxanthoma elasticum (PXE) is a heritable multisystem ectopic calcification disorder. The gene responsible for PXE, ABCC6, encodes ABCC6, a hepatic efflux transporter regulating extracellular inorganic pyrophosphate (PPi), a potent endogenous calcification inhibitor. Recent studies demonstrated that in addition to the deficiency of plasma PPi, the activated DDR/PARP signaling in calcified tissues provides an additional possible mechanism of ectopic calcification in PXE. This study examined the effects of etidronate (ETD), a stable PPi analog, and its combination with minocycline (Mino), a potent inhibitor of DDR/PARP, on ectopic calcification in an Abcc6-/- mouse model of PXE. Abcc6-/- mice, at 4 weeks of …

Molecular Event In Hrp Apoptosis, Laura Valdez

Research Colloquium

Background: Human retinal pericytes (HRP) are contractile cells providing support for endothelial cells of capillaries, essential in the regulation of retinal vasculature. Early stages of DR are characterized by the loss of HRP, leading to angiogenesis. Our preliminary studies identified monocyte-derived macrophages secrete TGF-β1, inducing the expression and secretion of a TGFβ1-Induced, pro-apoptotic BIGH3 protein leading to apoptosis of HRP. Based on a preliminary study in renal cells (unpublished data), CTP with an RGD domain is released from BIGH3 by proteolysis leading to renal cell apoptosis. In the present study, we employed Western Blots to determine if a similar molecular …

Irbp In Diabetic Retinopathy – Cell Culture & Ophthalmic Pathology Studies, Laura Valdez

Research Colloquium

Background: Interphotoreceptor-Retinoid-Binding-Protein (IRBP) is restricted to the subretinal space by the external limiting membrane and RPE zonulae occludens. Its expression is reduced in diabetic retinopathy (DR) and increased expression is protective. Hypoxia decreases viable conelike photoreceptors (661W) but increased VEGF, suggesting a role of photoreceptors in proliferative DR (PDR) (Rodriguez et al, Arch Clin Exp. Ophthal 3:23,2021). Here, we investigated the effects of high glucose and VEGF on IRBP expression by 661W and rod-like Y79 cells and distribution of IRBP and albumin in human globes with PDR and NPDR.

Methods:  661W and Y79 cells were cultured in DMEM or RPMI …

Global Effect Of Modifiable Risk Factors On Cardiovascular Disease And Mortality, Global Cardiovascular Risk Consortium, Christina Magnussen, Francisco M Ojeda, Darryl P Leong, Jesus Alegre-Diaz, Philippe Amouyel, Larissa Aviles-Santa, Dirk De Bacquer, Christie M Ballantyne, Antonio Bernabé-Ortiz, Martin Bobak, Hermann Brenner, Rodrigo M Carrillo-Larco, James De Lemos, Annette Dobson, Marcus Dörr, Chiara Donfrancesco, Wojciech Drygas, Robin P Dullaart, Gunnar Engström, Marco M Ferrario, Jean Ferrières, Giovanni De Gaetano, Uri Goldbourt, Clicerio Gonzalez, Guido Grassi, Allison M Hodge, Kristian Hveem, Licia Iacoviello, M Kamran Ikram, Vilma Irazola, Modou Jobe, Pekka Jousilahti, Pontiano Kaleebu, Maryam Kavousi, Frank Kee, Davood Khalili, Wolfgang Koenig, Anna Kontsevaya, Kari Kuulasmaa, Karl J Lackner, David M Leistner, Lars Lind, Allan Linneberg, Thiess Lorenz, Magnus Nakrem Lyngbakken, Reza Malekzadeh, Sofia Malyutina, Ellisiv B Mathiesen, Olle Melander, Andres Metspalu, J Jaime Miranda, Marie Moitry, Joseph Mugisha, Mahdi Nalini, Vijay Nambi, Toshiharu Ninomiya, Karen Oppermann, Eleonora D'Orsi, Andrzej Pająk, Luigi Palmieri, Demosthenes Panagiotakos, Arokiasamy Perianayagam, Annette Peters, Hossein Poustchi, Andrew M Prentice, Eva Prescott, Ulf Risérus, Veikko Salomaa, Susana Sans, Satoko Sakata, Ben Schöttker, Aletta E Schutte, Sadaf G Sepanlou, Sanjib Kumar Sharma, Jonathan E Shaw, Leon A Simons, Stefan Söderberg, Abdonas Tamosiunas, Barbara Thorand, Hugh Tunstall-Pedoe, Raphael Twerenbold, Diego Vanuzzo, Giovanni Veronesi, Julia Waibel, S Goya Wannamethee, Masafumi Watanabe, Philipp S Wild, Yao Yao, Yi Zeng, Andreas Ziegler, Stefan Blankenberg

Faculty, Staff and Students Publications

BACKGROUND: Five modifiable risk factors are associated with cardiovascular disease (CVD) and all-cause mortality. The regional and sex-specific prevalence of these modifiable risk factors and their impact on CVD and all-cause mortality have not been evaluated using individual-level data.

METHODS: The Global Cardiovascular Risk Consortium harmonized individual-level data from 112 cohort studies conducted in 34 countries and 8 geographic regions. Associations between body-mass index, systolic blood pressure, non-high-density lipoprotein cholesterol, smoking, and diabetes with incident CVD and all-cause mortality were examined using Cox regression analyses and stratified by geographic region, age and sex. Population-attributable fractions were estimated for 10-year incident …

Sars-Cov-2: Tale Of A Microscopic Murderer, Josiah P. Garner

Quest

Independent Study

Research in progress for BIOL1406: Biology for Science Majors I

Faculty Mentor: Amina Tassa, Ph.D.

I am delighted to introduce Josiah Garner’s “SARS-CoV-2: Tale of a Microscopic Murderer.” This independent study assignment explores the impact of a novel, deadly, and worldwide virus. The assignment also examines the fast development of vaccines to control the spread and reduce the symptoms of the virus.

Josiah’s paper focuses on the early history of the emergence of COVID-19, the world response, and vaccine development. He demonstrates critical thinking skills and effectively utilizes various research methods to obtain and communicate his information. Josiah …

Scribbledom: Using Scribble-Annotated Histology Images To Identify Domains In Spatial Transcriptomics Data, Mohammad Nuwaisir Rahman, Abdullah Al Noman, Abir Mohammad Turza, Mohammed Abid Abrar, Md Abul Hassan Samee, M Saifur Rahman

Faculty, Staff and Students Publications

Motivation

Spatial domain identification is a very important problem in the field of spatial transcriptomics. The state-of-the-art solutions to this problem focus on unsupervised methods, as there is lack of data for a supervised learning formulation. The results obtained from these methods highlight significant opportunities for improvement.

Results

In this article, we propose a potential avenue for enhancement through the development of a semi-supervised convolutional neural network based approach. Named “ScribbleDom”, our method leverages human expert’s input as a form of semi-supervision, thereby seamlessly combines the cognitive abilities of human experts with the computational power of machines. ScribbleDom incorporates a …

Spa-Stocsy: An Automated Tool For Identifying Annotated And Non-Annotated Metabolites In High-Throughput Nmr Spectra, Xu Han, Wanli Wang, Li-Hua Ma, Ismael Ai-Ramahi, Juan Botas, Kevin Mackenzie, Genevera I Allen, Damian W Young, Zhandong Liu, Mirjana Maletic-Savatic

Faculty, Staff and Students Publications

MOTIVATION: Nuclear magnetic resonance spectroscopy (NMR) is widely used to analyze metabolites in biological samples, but the analysis requires specific expertise, it is time-consuming, and can be inaccurate. Here, we present a powerful automate tool, SPatial clustering Algorithm-Statistical TOtal Correlation SpectroscopY (SPA-STOCSY), which overcomes challenges faced when analyzing NMR data and identifies metabolites in a sample with high accuracy.

RESULTS: As a data-driven method, SPA-STOCSY estimates all parameters from the input dataset. It first investigates the covariance pattern among datapoints and then calculates the optimal threshold with which to cluster datapoints belonging to the same structural unit, i.e. the metabolite. …

Chronic Kidney Disease Promotes Atrial Fibrillation Via Inflammasome Pathway Activation, Jia Song, Jose Alberto Navarro-Garcia, Jiao Wu, Arnela Saljic, Issam Abu-Taha, Luge Li, Satadru K Lahiri, Joshua A Keefe, Yuriana Aguilar-Sanchez, Oliver M Moore, Yue Yuan, Xiaolei Wang, Markus Kamler, William E Mitch, Gema Ruiz-Hurtado, Zhaoyong Hu, Sandhya S Thomas, Dobromir Dobrev, Xander Ht Wehrens, Na Li

Faculty, Staff and Students Publications

Chronic kidney disease (CKD) is associated with a higher risk of atrial fibrillation (AF). The mechanistic link between CKD and AF remains elusive. IL-1β, a main effector of NLR family pyrin domain-containing 3 (NLRP3) inflammasome activation, is a key modulator of conditions associated with inflammation, such as AF and CKD. Circulating IL-1β levels were elevated in patients with CKD who had AF (versus patients with CKD in sinus rhythm). Moreover, NLRP3 activity was enhanced in atria of patients with CKD. To elucidate the role of NLRP3/IL-1β signaling in the pathogenesis of CKD-induced AF, Nlrp3-/- and WT mice were subjected to …

Kinome Reprogramming Is A Targetable Vulnerability In Esr1 Fusion-Driven Breast Cancer, Xuxu Gou, Beom-Jun Kim, Meenakshi Anurag, Jonathan T Lei, Meggie N Young, Matthew V Holt, Diana Fandino, Craig T Vollert, Purba Singh, Mohammad A Alzubi, Anna Malovannaya, Lacey E Dobrolecki, Michael T Lewis, Shunqiang Li, Charles E Foulds, Matthew J Ellis

Faculty, Staff and Students Publications

Transcriptionally active ESR1 fusions (ESR1-TAF) are a potent cause of breast cancer endocrine therapy (ET) resistance. ESR1-TAFs are not directly druggable because the C-terminal estrogen/anti-estrogen-binding domain is replaced with translocated in-frame partner gene sequences that confer constitutive transactivation. To discover alternative treatments, a mass spectrometry (MS)-based kinase inhibitor pulldown assay (KIPA) was deployed to identify druggable kinases that are upregulated by diverse ESR1-TAFs. Subsequent explorations of drug sensitivity validated RET kinase as a common therapeutic vulnerability despite remarkable ESR1-TAF C-terminal sequence and structural diversity. Organoids and xenografts from a pan-ET-resistant patient-derived xenograft model that harbors the ESR1-e6>YAP1 TAF were …

Heterocyclic Merging Of Stereochemically Diverse Chiral Piperazines And Morpholines With Indazoles, Amol B Viveki, Timothy M Mansfield, Kevin A Tran, Evan Lenkeit, Kevin R Mackenzie, Damian W Young, Srinivas Chamakuri

Faculty, Staff and Students Publications

We report a heterocyclic merging approach to construct novel indazolo-piperazines and indazolo-morpholines. Starting from chiral diamines and amino alcohols, novel regiochemically (1,3 and 1,4) and stereochemically diverse (relative and absolute) cohorts of indazolo-piperazines and indazolo-morpholines were obtained within six or seven steps. The key transformations involved are a Smiles rearrangement to generate the indazole core structure and a late-stage Michael addition to build the piperazine and morpholine heterocycles. We further explored additional vector diversity by incorporating substitutions on the indazole aromatic ring, generating a total of 20 unique, enantiomerically pure heterocyclic scaffolds.

Raman Spectral Cytopathology For Cancer Diagnostic Applications, Fiona Lyng, Damian Traynor, Isha Behl, Declan O'Dea, Hugh Byrne

Books/Book Chapters

Histopathology is currently regarded as the “gold standard” patient sampling technique for cancer diagnostics. It involves extraction of a tissue sample, or biopsy, which is then sectioned and stained for evaluation by a pathologist [1]. Cytopathology, on the other hand, is the field of disease diagnosis at the cellular level [2], necessitating only the microscopic evaluation of samples of cells which can be harvested by less invasive methods such as exfoliative brushing, needle probes or from biofluids. Based on the identification of abnormalities in cellular appearance, cytopathology is currently widely used to aid in the screening of cancer, as well …

Combination Therapy Of Triple-Negative Breast Cancer With Paclitaxel And Ambrisentan, A Selective Antagonist Of The Endothelin Type A Receptor, Inhibits Tumor Growth And Metastasis, Farah Nasser Almahrook

Theses

Cancer treatment is a big challenge especially when associated with metastasis. Moreover, the importance of using combination therapy is increasing, especially for highly invasive, drug-resistant cancers, such as triple-negative breast cancer (TNBC). Ambrisentan, a selective antagonist of the endothelin type A receptor (ETAR) was previously shown to reduce metastasis of TNBC in a preclinical tumor model when used prophylactically. In the current study, we investigated the therapeutic potential of Ambrisentan, given as monotherapy or in combination with Paclitaxel, on TNBC. The data show that oral dosing with Ambrisentan led to a significant retardation in tumor growth and metastasis. Moreover, combining …

Structural Insights Into The Cl-Par-4 Protein: Ionic Requirements, Conformational Transitions, And Interaction With Cisplatin, Krishna Kumar Raut

Chemistry & Biochemistry Theses & Dissertations

Cancer continues to be the leading global cause of death, with challenges in early diagnosis, drug resistance, non-specific drug targeting, and cancer recurrence and metastasis posing formidable obstacles in cancer therapy. In this context, Prostate Apoptosis Response-4 (Par-4), a pro-apoptotic tumor suppressor protein, emerged as a promising therapeutic target due to its ability to selectively induce apoptosis in cancer cells, thereby minimizing the drug-associated adverse effects. However, a comprehensive understanding of the structural features of Par-4, specifically the caspase-cleaved fragment (cl-Par-4), is crucial for therapeutic advancements.

This dissertation investigated the effects of various ions, both monovalent and divalent, on the …

Copy Number Variation That Influences The Ionizing Radiation Sensitivity Of Oral Squamous Cell Carcinoma, Tadahide Izumi, Piotr G. Rychahou, Li Chen, Molly H. Smith, Joseph Valentino

Markey Cancer Center Faculty Publications

Genome instability in cancer cells causes not only point mutations but also structural variations of the genome, including copy number variations (CNVs). It has recently been proposed that CNVs arise in cancer to adapt to a given microenvironment to survive. However, how CNV influences cellular resistance against ionizing radiation remains unknown. PRMT5 (protein arginine methyltransferase 5) and APE1 (apurinic/apyrimidinic endonuclease 1), which enhance repair of DNA double-strand breaks and oxidative DNA damage, are closely localized in the chromosome 14 of the human genome. In this study, the genomics data for the PRMT5 and APE1 genes, including their expression, CNVs, and …

Distinct Camp Signaling Microdomains Differentially Regulate Melanosomal Ph And Pigmentation, Maftuna Yusupova, Dalee Zhou, Jaewon You, Jeydi Gonzalez-Guzman, Megha B. Ghanta, Hong Pu, Zalfa Abdel-Malek, Qiuying Chen, Steven S. Gross, John August D'Orazio, Shosuke Ito, Kazumasa Wakamatsu, Melissa L. Harris, Jonathan H. Zippin

Markey Cancer Center Faculty Publications

cAMP signaling is a well-established regulator of melanin synthesis. Two distinct cAMP signaling pathways—the transmembrane adenylyl cyclase pathway, activated primarily by the MC1R, and the soluble adenylyl cyclase (sAC) pathway—affect melanin synthesis. The sAC pathway affects melanin synthesis by regulating melanosomal pH, and the MC1R pathway affects melanin synthesis by regulating gene expression and post-translational modifications. However, whether MC1R genotype affects melanosomal pH is poorly understood. We now report that loss of function MC1R does not affect melanosomal pH. Thus, sAC signaling appears to be the only cAMP signaling pathway that regulates melanosomal pH. We also addressed whether MC1R genotype …

Phosphatidic Acid Binding To Patched Contributes To The Inhibition Of Smoothened And Hedgehog Signaling In Drosophila Wing Development, Jie Zhang, Yajuan Liu, Chi Wang, Craig W. Vander Kooi, Jianhang Jia

Markey Cancer Center Faculty Publications

Hedgehog (Hh) signaling controls growth and patterning during embryonic development and homeostasis in adult tissues. Hh binding to the receptor Patched (Ptc) elicits intracellular signaling by relieving Ptc-mediated inhibition of the transmembrane protein Smoothened (Smo). We uncovered a role for the lipid phosphatidic acid (PA) in the regulation of the Hh pathway in Drosophila melanogaster. Deleting the Ptc C-terminal tail or mutating the predicted PA-binding sites within it prevented Ptc from inhibiting Smo in wing discs and in cultured cells. The C-terminal tail of Ptc directly interacted with PA in vitro, an association that was reduced by Hh, and increased …

Regulated Translocation Of Neutral Sphingomyelinase-2 To The Plasma Membrane Drives Insulin Resistance In Steatotic Hepatocytes, Salim S. El-Amouri, Alexander A. Karakashian, Erhard Bieberich, Mariana N. Nikolova‑Karakashian

Markey Cancer Center Faculty Publications

Abstract Obesity-associated diabetes is linked to the accumulation of ceramide in various organs, including the liver. The exact mechanisms by which ceramide contributes to diabetic pathology are unclear, but one proposed scenario is that ceramide accumulation may inhibit insulin signaling pathways. It is unknown however whether the excess ceramide is generated proximal to the insulin receptor, that is, at the plasma membrane (PM), where it could affect the insulin signaling pathway directly, or the onset of insulin resistance is due to ceramide- induced mitochondrial dysfunction and/or lipotoxicity. Using hepatic cell lines and primary cultures, gain- and loss- of function approach, …

Type 1 Diabetes Genetic Risk Score Differentiates Subgroups Of Ketosis-Prone Diabetes, Deborah Osafehinti, Surya N Mulukutla, Christiane S Hampe, Ruchi Gaba, Nalini Ram, Michael N Weedon, Richard A Oram, Ashok Balasubramanyam

Faculty, Staff and Students Publications

OBJECTIVE: To determine whether genetic risk for type 1 diabetes (T1D) differentiates the four Aβ subgroups of ketosis-prone diabetes (KPD), where A+ and A- define the presence or absence of islet autoantibodies and β+ and β- define the presence or absence of β-cell function.

RESEARCH DESIGN AND METHODS: We compared T1D genetic risk scores (GRS) of patients with KPD across subgroups, race/ethnicity, β-cell function, and glycemia.

RESULTS: Among 426 patients with KPD (54% Hispanic, 31% African American, 11% White), rank order of GRS was A+β- > A+β+ = A-β- > A-β+. GRS of A+β- KPD was lower than that of a T1D …

Natural Remedies To Combat Aberrant Hallmark Signatures Including Altered Glycosylation In Oral Carcinoma, Kruti A. Mehta, Jayendra B. Patel, Prabhudas S. Patel

Research Symposium

Background: Tobacco associated oral cancers remain a major concern in India with higher incidence and mortality making it an Indian-centric burning issue. To combat this dreadful disease, we investigated effects of certain natural compounds on the hallmark signatures including glycosylation transcripts levels in oral carcinoma.

Methods: The tongue carcinoma cells- SAS cells were treated with tobacco compounds, natural compounds and Cisplatin. RNA was isolated from the cells and converted to cDNA. RT-qPCR was performed to evaluate expression levels of various genes.

Results: The treatment of tobacco compounds resulted in similar pattern of altered makers (ST3GAL1, NEU3, FUT5, FUT6, MMP2, BCL2) …

Hpv Imprints In Western India: The Overlooked Criteria For Cancer Profiling, Ashi R. Thobias, Jayendra B. Patel, Prabhudas P. Patel

Research Symposium

Background: In India, HPV infection detection for cancer-typing has been largely evaded. Especially, data on prevalence of HPV types other than the highly prevalent HPV 16 and 18 are lacking, particularly from the western region. Thus, present study aimed to evaluate prevalence of HPV strains in three most prevailing cancers in India i.e. cervical, oral and oropharyngeal cancer.

Materials & methods: DNA was isolated from tissue samples of 400 cervical cancer cases, 127 oral cancer cases and 75 oropharyngeal cancer cases and endpoint PCR was performed using degenerative primers MY 09/11, GP 5+/6+ and CP I/II. TS-PCR was conducted to …