Medical Cell Biology Commons^™

Mir-196a Upregulation Contributes To Gefitinib Resistance Through Inhibiting Gltp Expression, Bing-Jie Liu, Fang-Fang Li, Yun-Xia Xie, Chong-Yuan Fan, Wen-Jing Liu, Jian-Ge Qiu, Bing-Hua Jiang

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Tyrosine kinase inhibitor (TKI) therapy has greatly improved lung cancer survival in patients with epidermal growth factor receptor (EGFR) mutations. However, the development of TKI-acquired resistance is the major problem to be overcome. In this study, we found that miR-196a expression was greatly induced in gefitinib-resistant lung cancer cells. To understand the role and mechanism of miR-196a in TKI resistance, we found that miR-196a-forced expression alone increased cell resistance to gefitinib treatment in vitro and in vivo by inducing cell proliferation and inhibiting cell apoptosis. We identified the transcription factor nuclear factor erythroid 2-related factor 2 (NRF2) bound to the …

The Role Of Decorin Proteoglycan In Mitophagy., Thomas Neill, Renato V. Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Proteoglycans are emerging as critical regulators of intracellular catabolism. This rise in prominence has transformed our basic understanding and alerted us to the existence of non-canonical pathways, independent of nutrient deprivation, that potently control the autophagy downstream of a cell surface receptor. As a member of the small leucine-rich proteoglycan gene family, decorin has single-handedly pioneered the connection between extracellular matrix signaling and autophagy regulation. Soluble decorin evokes protracted endothelial cell autophagy via Peg3 and breast carcinoma cell mitophagy via mitostatin by interacting with VEGFR2 or the MET receptor tyrosine kinase, respectively. In this paper, we give a mechanistic perspective …

Ras-Mediated Tumor Stress Adaptation And The Targeting Opportunities It Presents, Alexandra Redding, A E Aplin, Elda Grabocka

Department of Cancer Biology Faculty Papers

Cellular stress is known to function in synergistic cooperation with oncogenic mutations during tumorigenesis to drive cancer progression. Oncogenic RAS is a strong inducer of a variety of pro-tumorigenic cellular stresses, and also enhances the ability of cells to tolerate these stresses through multiple mechanisms. Many of these oncogenic, RAS-driven, stress-adaptive mechanisms have also been implicated in tolerance and resistance to chemotherapy and to therapies that target the RAS pathway. Understanding how oncogenic RAS shapes cellular stress adaptation and how this functions in drug resistance is of vital importance for identifying new therapeutic targets and therapeutic combinations to treat RAS-driven …

A Twist To The Kirby-Bauer Disk Diffusion Susceptibility Test: An Accessible Laboratory Experiment Comparing Haloferax Volcanii And Escherichia Coli Antibiotic Susceptibility To Highlight The Unique Cell Biology Of Archaea, Heather Schiller, Criston Young, Stefan Schulze, Manuela Tripepi, Mechthild Pohlschroder

College of Life Sciences Faculty Papers

Archaea, once thought to only live in extreme environments, are present in many ecosystems, including the human microbiome, and they play important roles ranging from nutrient cycling to bioremediation. Yet this domain is often overlooked in microbiology classes and rarely included in laboratory exercises. Excluding archaea from high school and undergraduate curricula prevents students from learning the uniqueness and importance of this domain. Here, we have modified a familiar and popular microbiology experiment-the Kirby-Bauer disk diffusion antibiotic susceptibility test-to include, together with the model bacterium Escherichia coli, the model archaeon Haloferax volcanii. Students will learn the differences and similarities between …

Reactive Oxygen Species Reprogram Macrophages To Suppress Antitumor Immune Response Through The Exosomal Mir-155-5p/Pd-L1 Pathway, Xiang Li, Shaomin Wang, Wei Mu, Jennifer Barry, Anna Han, Richard L Carpenter, Bing-Hua Jiang, Stephen C Peiper, M G Mahoney, A E Aplin, Hong Ren, Jun He

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Background: Cancer cells have an imbalance in oxidation-reduction (redox) homeostasis. Understanding the precise mechanisms and the impact of the altered redox microenvironment on the immunologic reaction to tumors is limited.

Methods: We isolated exosomes from ovarian cancer cells through ultracentrifuge and characterized by Western-blots and Nanoparticle Tracking Analysis. 2D, 3D-coculture tumor model, and 3D live cell imaging were used to study the interactions between tumor cells, macrophages and CD3 T cells in vitro. The role of exosomal miR-155-5p in tumor growth was evaluated in xenograft nude mice models and immune-competent mice models. Flow cytometry and flow sorting were used to …

Novel Oncogenic Transcription Factor Cooperation In Rb-Deficient Cancer, Amy C. Mandigo, Ayesha A Shafi, Jennifer J Mccann, Wei Yuan, Talya Laufer, Denisa Bogdan, Lewis Gallagher, Emanuela Dylgjeri, Galina Semenova, Irina A Vasilevskaya, M J Schiewer, Chris M Mcnair, Johann S De Bono, Karen E Knudsen

Department of Cancer Biology Faculty Papers

The retinoblastoma tumor suppressor (RB) is a critical regulator of E2F-dependent transcription, controlling a multitude of protumorigenic networks including but not limited to cell-cycle control. Here, genome-wide assessment of E2F1 function after RB loss in isogenic models of prostate cancer revealed unexpected repositioning and cooperation with oncogenic transcription factors, including the major driver of disease progression, the androgen receptor (AR). Further investigation revealed that observed AR/E2F1 cooperation elicited novel transcriptional networks that promote cancer phenotypes, especially as related to evasion of cell death. These observations were reflected in assessment of human disease, indicating the clinical relevance of the AR/E2F1 cooperome …

Microbial Cell Factory Of Baccatin Iii Preparation In Escherichia Coli By Increasing Dbat Thermostability And In Vivo Acetyl-Coa Supply, Jia-Jun Huang, Tao Wei, Zhi-Wei Ye, Qian-Wang Zheng, Bing-Hua Jiang, Wen-Feng Han, An-Qi Ye, Pei-Yun Han, Li-Qiong Guo, Jun-Fang Lin

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Given the rapid development of genome mining in this decade, the substrate channel of paclitaxel might be identified in the near future. A robust microbial cell factory with gene dbat, encoding a key rate-limiting enzyme 10-deacetylbaccatin III-10-O-transferase (DBAT) in paclitaxel biosynthesis to synthesize the precursor baccatin III, will lay out a promising foundation for paclitaxel de novo synthesis. Here, we integrated gene dbat into the wild-type Escherichia coli BW25113 to construct strain BWD01. Yet, it was relatively unstable in baccatin III synthesis. Mutant gene dbat S189V with improved thermostability was screened out from a semi-rational mutation library …

Opa1 Modulates Mitochondrial Ca 2+ Uptake Through Er-Mitochondria Coupling, Benjamín Cartes-Saavedra, Josefa Macuada, Daniel Lagos, Duxan Arancibia, María E Andrés, Patrick Yu-Wai-Man, György Hajnóczky, Verónica Eisner

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Autosomal Dominant Optic Atrophy (ADOA), a disease that causes blindness and other neurological disorders, is linked to OPA1 mutations. OPA1, dependent on its GTPase and GED domains, governs inner mitochondrial membrane (IMM) fusion and cristae organization, which are central to oxidative metabolism. Mitochondrial dynamics and IMM organization have also been implicated in Ca2+ homeostasis and signaling but the specific involvements of OPA1 in Ca2+ dynamics remain to be established. Here we studied the possible outcomes of OPA1 and its ADOA-linked mutations in Ca2+ homeostasis using rescue and overexpression strategies in Opa1-deficient and wild-type murine embryonic fibroblasts (MEFs), respectively and in …

Phytochemical Constituents Of Aquilaria Malaccensis Leaf Extract And Their Anti-Inflammatory Activity Against Lps/Ifn-Γ-Stimulated Raw 264.7 Cell Line, Eman Ramadan, Manar A. Eissa, Yumi Z. H-Y Hashim, Dina M. El-Kersh

Pharmacy

This study aims to identify the major phytochemical constituents in Aquilaria malaccensis (Thymelaeaceae) ethanolic leaf extract (ALEX-M) and elucidate their ability to suppress nitric oxide (NO) production from a murine macrophage-like cell line (RAW 264.7) stimulated by lipopolysaccharide (LPS) and interferon-γ (IFN-γ). Dichloromethane (DCM) and ethyl acetate (EtOAc) fractions of ALEX-M were subjected to column chromatography. Eight known compounds were isolated for the first time from this species. Compounds were identified using spectroscopic techniques (IR, UV, HRESIMS, and 1D and 2D NMR). Anti-inflammatory activity of both extract and isolated compounds were investigated in vitro. The fractions offered the isolation of …

Uveitis-Mediated Immune Cell Invasion Through The Extracellular Matrix Of The Lens Capsule, Jodirae Dedreu, Sonali Pal-Ghosh, Mary J Mattapallil, Rachel R Caspi, Mary Ann Stepp, A Sue Menko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

While the eye is considered an immune privileged site, its privilege is abrogated when immune cells are recruited from the surrounding vasculature in response to trauma, infection, aging, and autoimmune diseases like uveitis. Here, we investigate whether in uveitis immune cells become associated with the lens capsule and compromise its privilege in studies of C57BL/6J mice with experimental autoimmune uveitis. These studies show that at D14, the peak of uveitis in these mice, T cells, macrophages, and Ly6G/Ly6C+ immune cells associate with the lens basement membrane capsule, burrow into the capsule matrix, and remain integrated with the capsule as immune …

Monitoring The Systemic Immune System To Understand And Improve The Efficacy Of Immunotherapy For Metastatic Osteosarcoma, Justin Edward Markel

Graduate Theses, Dissertations, and Problem Reports

Osteosarcoma (OS) is a complex tumor with no effective targeted therapies due to its genomic heterogeneity and pleomorphism. The immune response it creates, particularly against metastatic lesions, is considerable; however, various suppressive mechanisms induced by the tumor prohibit its effectiveness. The presence of infiltrating lymphocytes suggests that therapeutic disinhibition through checkpoint blockade could increase antitumor immunity, though none have been successful in clinical trials. The complexities of the immune response to OS tumors have yet to be unraveled; however, there is evidence to suggest that cell-mediated immunity (CMI, specifically T cells, Natural Killer [NK] cells, and myeloid-lineage cells [MLCs]) plays …

Regulation Of The Protease Activity For The Mitochondrial Omi/Htra2, Simon Larson

Honors Undergraduate Theses

Human High Temperature requirement A2 (HtrA2) also known as Omi, is a serine protease located in the mitochondria with an important function in both cell survival and death. My results show the proteolytic activity of Omi/HtrA2 varies under different conditions. I characterized the optimal condition for Omi/HtrA2 protease activity using an in vitro assay system. Additionally, I identified a new allosteric regulation of Omi/HtrA2 through interaction with a specific substrate, the MUL1 protein. MUL1 is a multifunctional E3 ubiquitin ligase anchored in the outer mitochondrial membrane with domains both inside mitochondria and in the cytoplasm. The data shown here strongly …

The Effect Of Creatine On Immortalized Schwann Cell Proliferation, Peyton Kimmel, Caitlyn Henry, Angela Asirvatham

Student Research Poster Presentations 2022

Creatine is an important component of the high-energy phosphate transfer to regulate cellular levels of ATP. The functions of creatine supplementation are well studied in the muscular and skeletal system, however the impact of creatine in the nervous system, specifically Schwann cells, is relatively unknown. Schwann cell growth in vitro is facilitated by heregulin, a neuron secreted growth factor, and forskolin, a pharmacological agent that activates cAMP. In peripheral nervous system injuries, recovery time is based around Schwann cell’s ability to proliferate and differentiate, and it is unknown what role creatine plays in this process. It was hypothesized that increasing …

Extracellular Mechanotransduction, Stephen J. Haller, Andrew T. Dudley

Journal Articles: Genetics, Cell Biology & Anatomy

We highlight the force-sensing function of extracellular matrix and present a complementary mechanotransduction paradigm.

Extracellular Matrix Guidance Of Autophagy: A Mechanism Regulating Cancer Growth, Carolyn Chen, Renato V. Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The extracellular matrix (ECM) exists as a dynamic network of biophysical and biochemical factors that maintain tissue homeostasis. Given its sensitivity to changes in the intra- and extracellular space, the plasticity of the ECM can be pathological in driving disease through aberrant matrix remodelling. In particular, cancer uses the matrix for its proliferation, angiogenesis, cellular reprogramming and metastatic spread. An emerging field of matrix biology focuses on proteoglycans that regulate autophagy, an intracellular process that plays both critical and contextual roles in cancer. Here, we review the most prominent autophagic modulators from the matrix and the current understanding of the …

Interferon Gamma Release Assay Mitogen Responses In Covid-19, Dagan Coppock, Claire E. Zurlo, Jenna M. Meloni, Sara L. Goss, John J. Zurlo, Matthew A. Pettengill

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Background

Elevated cytokine release and T cell exhaustion have been associated with COVID-19 disease severity. T cell activity may be indirectly measured through interferon gamma release assays (IGRAs), which use mitogen stimulation of T lymphocytes as a positive control. In our institution, an unexpectedly high rate of indeterminate IGRAs was noted in COVID-19–positive patients. We aimed to evaluate the clinical characteristics associated with indeterminate IGRA results and the difference in mitogen responses between COVID-19–positive and COVID-19–negative patients.

Methods

We reviewed all patients, regardless of COVID status, who were admitted between March 1, 2020, and May 31, 2020, and for whom …

Sox10 Requirement For Melanoma Tumor Growth Is Due, In Part, To Immune-Mediated Effects, Sheera Rosenbaum, Manoela Tiago, Signe Caksa, Claudia Capparelli, Timothy J. Purwin, Gaurav Kumar, Mckenna Glasheen, Danielle Pomante, Daniel Kotas, I Chervoneva, A E Aplin

Department of Cancer Biology Faculty Papers

Developmental factors may regulate the expression of immune modulatory proteins in cancer, linking embryonic development and cancer cell immune evasion. This is particularly relevant in melanoma because immune checkpoint inhibitors are commonly used in the clinic. SRY-box transcription factor 10 (SOX10) mediates neural crest development and is required for melanoma cell growth. In this study, we investigate immune-related targets of SOX10 and observe positive regulation of herpesvirus entry mediator (HVEM) and carcinoembryonic-antigen cell-adhesion molecule 1 (CEACAM1). Sox10 knockout reduces tumor growth in vivo, and this effect is exacerbated in immune-competent models. Modulation of CEACAM1 expression but not HVEM elicits modest …

Lgr5 Regulation Of Stat3 Signaling And Drug Resistance In Colorectal Cancer, Tressie Posey, Tressie Alexandra Posey

The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences Dissertations and Theses (Open Access)

LGR5 Regulation of STAT3 Signaling and Drug Resistance in Colorectal Cancer

Tressie Alexandra Capri Posey B.S.

Advisory Professor: Kendra Carmon, Ph.D.

The greatest difficulty in treating colorectal cancer (CRC) is the development of drug resistance which leads to relapse after treatment and progression to metastasis. Cancer stem cells (CSCs) are believed to drive relapse because of their capacity to self-renew, acquire resistance mechanisms, and differentiate promoting tumor growth and heterogeneity. Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5), is a bona-fide marker of CSCs and has been considered a viable target for CSC specific therapeutic development. While we showed targeting LGR5 …

Atrx Inactivation And Idh1-R132h Drive Preferential Sensitivity To Proton Vs. X-Ray Radiotherapy In Glioma Stem Cells, Ángel Adrián Garcés

The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences Dissertations and Theses (Open Access)

Background: Glioma Stem Cells (GSCs) are self-renewable, treatment resistant cells in the glioma tumor mass known to promote tumor development. In contrast to traditional photon-based radiation therapy (XRT), proton radiation therapy (PRT) may induce more complex DNA damage and therefore might have the potential to eliminate GSCs. Although previous studies have individually linked IDH mutations, specifically IDH1^R132H, and ATRX inactivating mutations to improved patient outcomes and suppressed DNA damage repair compared to their respective wild-types, the mechanisms by which these two genetic alterations interact in GSCs treated with PRT compared to XRT are currently unknown. We hypothesize that …

Dysregulation Of Mir-21-Associated Mirna Regulatory Networks By Chronic Ethanol Consumption Impairs Liver Regeneration., Austin Parrish, Ankita Srivastava, Egle Juskeviciute, Jan B Hoek, Rajanikanth Vadigepalli

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Impaired liver regeneration has been considered as a hallmark of progression of alcohol-associated liver disease. Our previous studies demonstrated that in vivo inhibition of the microRNA (miRNA) miR21 can restore regenerative capacity of the liver in chronic ethanol-fed animals. The present study focuses on the role of microRNA regulatory networks that are likely to mediate the miR-21 action. Rats were chronically fed an ethanol-enriched diet along with pair-fed control animals and treated with AM21 (anti-miR-21), a locked nucleic acid antisense to miR-21. Partial hepatectomy (PHx) was performed and miRNA expression profiling over the course of liver regeneration was assessed. Our …