Cell and Developmental Biology Commons^™

Assessing The Outcomes Of Blocking Ccl2-Ccr2 Signaling Axis On Breast Cancer Brain Metastasis, Yutao Qi

Dissertations and Theses (Open Access)

Breast cancer brain metastases have remained one of the most intense challenges for precision cancer therapeutics, but current treatment options are limited and not curative. Recently, our lab reported that adoptive PTEN downregulation in metastatic breast tumor cells activates PI3K/NF-ƙB signaling and increases the secretion of the chemokine CCL2, which enhances the chemotaxis of CCR2⁺ myeloid cells, a major subpopulation of bone marrow-derived myeloid cells (BMDMs), from peripheral blood into the brain tumor microenvironment (TME), eventually promoting brain metastasis outgrowth by driving immune suppression. Here, in this project we have been aiming to develop effective therapies by immune-modulating the …

Mitochondrial Transfer From Mesenchymal Stem Cells Improves Neuronal Metabolism After Oxidant Injury In Vitro: The Role Of Miro1, Nancy Tseng, Scott C Lambie, Christopher Q Huynh, Bridget Sanford, Manisha Patel, Paco S Herson, D Ryan Ormond

Faculty, Staff and Students Publications

Stroke-induced cerebral ischemia is a major cause of death and disability. The disruption of blood flow results in neuronal and glial cell death leading to brain injury. Reperfusion restores oxygen to the affected tissue, but can also cause damage through an enhanced oxidative stress and inflammatory response. This study examines mitochondrial transfer from MSC to neurons and the role it plays in neuronal preservation after oxidant injury. We observed the transfer of mitochondria from MSC to mouse neurons in vitro following hydrogen peroxide exposure. The observed transfer was dependent on cell-to-cell contact and led to increased neuronal survival and improved …

Disruption Of Dna Polymerase Zeta Promotes An Innate Immune Response, Sara Martin

Dissertations and Theses (Open Access)

DNA polymerase ζ (pol ζ) is a specialized polymerase that protects cells from the consequences of DNA damage and stress. Without pol ζ function mammalian cells and yeast are exquisitely sensitive to genotoxic stresses including ultraviolet irradiation and platinum compounds such as the chemotherapeutic agent cisplatin. This elevated sensitivity arises from the central role of pol ζ in lesion bypass. Pol ζ is also required to protect cells from endogenous genomic damage or stress. In primary mammalian cells, the function of pol ζ is required for genome protection and normal proliferation. Immortalized Rev3lknockout (KO) MEFs are under considerable constitutive …

Calcium Dyshomeostasis In Neurodegeneration, Nicholas Emanuel Karagas

Dissertations and Theses (Open Access)

Neurodegenerative diseases, despite constituting a major and growing cause of mortality globally, have few effective treatments. In order to develop novel therapeutics to combat neurodegeneration, a better understanding of the molecular mechanisms underlying these diseases is needed. Neurons rely on Ca²⁺ to mediate many of their unique functions, and aberrant Ca²⁺ signaling has been broadly implicated in neurodegeneration. The goal of this dissertation is to delineate specific examples of Ca²⁺ dyshomeostasis that I have uncovered in Drosophila models of neurodegeneration.

I first define the role a neurodegeneration-associated mutation plays in perturbing presynaptic [Ca²⁺], which is …

Subclonal Evolution Of Chronic Lymphocytic Leukemia After Allogeneic T Cell Therapies, Haven Garber

Dissertations and Theses (Open Access)

Subclonal evolution of chronic lymphocytic leukemia after allogeneic T-cell therapies

Haven Garber, MD

Advisory Professor: Jeffrey Molldrem, MD

Intratumoral genetic heterogeneity describes the molecular differences among subclones within a tumor and is a major barrier to effective therapy in many solid and liquid cancers, including chronic lymphocytic leukemia (CLL). Rare, treatment-resistant subclones can expand to compose relapsed disease during tumor evolution. Examination of malignant evolution in the context of specific treatment provides insight into the molecular lesions that mediate therapeutic response and resistance. Both chemotherapy and targeted therapy were shown to precipitate CLL subclonal evolution. We hypothesized that allogeneic T-cell …

P53 Drives A Transcriptional Program That Elicits A Non-Cell-Autonomous Response And Alters Cell State In Vivo, Sydney Moyer

Dissertations and Theses (Open Access)

Cell stress and DNA damage activate the tumor suppressor p53, triggering transcriptional activation of a myriad of target genes. The molecular, morphological, and physiological consequences of this activation remain poorly understood in vivo. We activated a p53 transcriptional program in mice by deletion of Mdm2, a gene which encodes the major p53 inhibitor. By overlaying tissue-specific RNA-sequencing data from pancreas, small intestine, ovary, kidney, and heart with existing p53 ChIP-sequencing, we identified a large repertoire of tissue-specific p53 genes and a common p53 transcriptional signature of seven genes which included Mdm2 but not p21. Global p53 activation …

Sine Oculis Homeobox Homolog 1 (Six1) Plays A Critical Role In The Progression Of Pulmonary Fibrosis., Cory Wilson

Dissertations and Theses (Open Access)

Idiopathic pulmonary fibrosis (IPF) is the most common idiopathic interstitial pneumonia with a median survival time of 2-4 years after diagnosis. The alarming mortality rate is due to the lack of effective treatments. IPF is a chronic disease that is characterized by alveolar destruction due to increasing extracellular matrix deposition that leads to poor lung compliance, impaired gas exchange, and ultimately respiratory failure. Repetitive alveolar epithelial injury is a central process to the underlying pathology with injury to the type II alveolar epithelial cells (AT2) specifically being a key player in the pathogenesis of IPF. Recent studies have shown that …

The Genome-Wide Roles Of The Lung Lineage Transcription Factor Nkx2-1 In The Regulation Of Opposing Cell Fates In Vivo, Danielle Renae Little

Dissertations and Theses (Open Access)

Lineage transcription factors mark, promote, and maintain multiple distinct cell types originating from a common progenitor. Despite their essential role, how such factors function and bind genome wide to orchestrate the epigenetic changes necessary to form and maintain these identities in vivo is unclear. One lineage transcription factor NK Homeobox 2-1 (NKX2-1) is expressed throughout the lung epithelium during development and was thought to be lost in the extraordinarily thin cell type required for gas exchange– the alveolar type 1 (AT1) cell. Complementing precise genetic knockouts with cell type-specific ChIP-seq, ATAC-seq, and scRNA-seq, our study shows that AT1 and AT2 …

The Role Of Daam1 In Kidney Development, Vanja Krneta-Stankic

Dissertations and Theses (Open Access)

Kidneys, like most organs in our bodies, consist of a network of epithelial tubules. Kidney tubules are called nephrons, and their morphology is important for kidney function. Nephrons develop from mesodermally derived aggregates of progenitor cells. The nephric progenitors organize into nephric tubules lined with hair-like sensory projections called cilia. Many diseases of the kidney are characterized by abnormal nephron morphology with current treatment aimed at symptom control. To understand the mechanisms underlying kidney diseases and achieve the development of novel therapies, a better understanding of how nephrons develop is needed. Although the actin cytoskeleton is critical for cell behaviors …

Micrornas Associated With Melanoma Inflammation And Response To Pd-1 Inhibition, Robert Szczepaniak Sloane

Dissertations and Theses (Open Access)

Melanoma is an aggressive malignancy of melanocytes with historically poor outcomes. Melanoma therapy has improved markedly over the past decade with advances in molecularly targeted agents and immunotherapies. Immune checkpoint inhibitors achieve T-cell mediated anti-tumor efficacy by blocking engagement of inhibitory checkpoints on T-cells to overcome immunosuppressive signals from tumor cells and the broader microenvironment. Despite these advances, there are a significant proportion of patients who do not benefit from existing immunotherapy strategies making it a priority to identify and target the mechanisms that confer resistance to therapy. We demonstrate that microRNAs are accurate markers of microenvironment composition with prognostic …

The Role Of Daam1 In Kidney Development, Vanja Krneta-Stankic

Dissertations and Theses (Open Access)

Kidneys, like most organs in our bodies, consist of a network of epithelial tubules. Kidney tubules are called nephrons, and their morphology is important for kidney function. Nephrons develop from mesodermally derived aggregates of progenitor cells. The nephric progenitors organize into nephric tubules lined with hair-like sensory projections called cilia. Many diseases of the kidney are characterized by abnormal nephron morphology with current treatment aimed at symptom control. To understand the mechanisms underlying kidney diseases and achieve the development of novel therapies, a better understanding of how nephrons develop is needed. Although the actin cytoskeleton is critical for cell behaviors …

Packaging And Secretion Of Airway Mucins, Oanh Ngoc Hoang

Dissertations and Theses (Open Access)

In the conducting airways of the lungs, the mobile mucus gel layer sits on top of the airway epithelium, and through ciliary beating it is propelled up the trachea into the pharynx where it is swallowed and cleared. This gel layer is composed of secreted mucins that become hydrated once reaching the airway lumen. Mucins are secreted at a baseline rate and at a stimulated rate, dependent on the amount of agonist. Baseline secretion is responsible for steady clearance of inhaled particles and pathogens. Stimulated secretion is thought to play a role in trapping helminths though mucus occlusion in small …

Qki-Mediated Cholesterol Biosynthesis In Eye Lens And Myelin Of The Central Nervous System, Seula Shin, Seula Shin

Dissertations and Theses (Open Access)

Cells obtain cholesterol in two ways, de novo biosynthesis and uptake from circulation. While most tissues utilize both sources, eye lens and brain depend extensively on cholesterol biosynthesis due to the limited supply from circulation. Lens cell membrane consists of highest portion of cholesterol. Brain is the most cholesterol-rich organ, which accounts for 23% of total cholesterol. Genetic mutations of cholesterol biosynthesis enzymes in humans and animal models present cataracts and hypomyelinating disorders linked to neurological impairment. Yet, it remains unclear how gene expression of cholesterol biosynthesis is regulated in lens and brain. Therefore, studying cholesterol biosynthesis in both tissues …

Ionic Mechanism Of Lysosomal Function And Cell Metabolism, Jian Xiong

Dissertations and Theses (Open Access)

Two Pore Channels (TPCs) are endolysosomal ion channels that are permeable to sodium and calcium. Defects in TPCs have been implicated to impair vesicle trafficking, autophagy and cell metabolism control; however, the detailed mechanism remains largely unknown. In this study, I show that TPCs are critical for appropriate cargo delivery to the lysosomes and deletion of either TPC1 or TPC2 leads to delayed clearance of autophagosomes, resulting in enlarged lysosomes and accumulated contents inside the lysosomes. Cells with both TPC deleted also exhibit 50% reduction in lysosomal amino acids under normal culture conditions, leading to reduced homeostatic mTORC1 activation.

Glutamine …

Fibroblast Heterogeneity In Pancreatic Cancer Immunity, Josephine Darpolor

Dissertations and Theses (Open Access)

Fibroblasts are a unique cell type defined by their mesenchymal phenotype and exclusion from epithelial, immune, and endothelial cell subsets. Although well studied in wound healing, cancer associated fibroblasts (CAFs) are incredibly heterogeneous, leading to contradictions as to the roles CAFs play in the tumor microenvironment (TME). CAFs were thought to be a barrier to treatment of pancreatic ductal adenocarcinoma (PDAC). However, general stromal targeting strategies have largely failed in the clinic likely due to the heterogeneity of CAFs in the TME. Therefore, our groups and others have worked to unravel the heterogeneity of CAFs in PDAC. In the works …

Qki-Mediated Cholesterol Biosynthesis In Eye Lens And Myelin Of The Central Nervous System, Seula Shin, Seula Shin

Dissertations and Theses (Open Access)

Cells obtain cholesterol in two ways, de novo biosynthesis and uptake from circulation. While most tissues utilize both sources, eye lens and brain depend extensively on cholesterol biosynthesis due to the limited supply from circulation. Lens cell membrane consists of highest portion of cholesterol. Brain is the most cholesterol-rich organ, which accounts for 23% of total cholesterol. Genetic mutations of cholesterol biosynthesis enzymes in humans and animal models present cataracts and hypomyelinating disorders linked to neurological impairment. Yet, it remains unclear how gene expression of cholesterol biosynthesis is regulated in lens and brain. Therefore, studying cholesterol biosynthesis in both tissues …

Improvement Of Cryo-Em Maps By Density Modification, Thomas C Terwilliger, Steven J Ludtke, Randy J Read, Paul D Adams, Pavel V Afonine

Faculty, Staff and Students Publications

A density-modification procedure for improving maps from single-particle electron cryogenic microscopy (cryo-EM) is presented. The theoretical basis of the method is identical to that of maximum-likelihood density modification, previously used to improve maps from macromolecular X-ray crystallography. Key differences from applications in crystallography are that the errors in Fourier coefficients are largely in the phases in crystallography but in both phases and amplitudes in cryo-EM, and that half-maps with independent errors are available in cryo-EM. These differences lead to a distinct approach for combination of information from starting maps with information obtained in the density-modification process. The density-modification procedure was …

Longitudinal Clonal Lineage Dynamics And Functional Characterization Of Pancreatic Cancer Chemo-Resistance And Metastasization, Chieh-Yuan Li

Dissertations and Theses (Open Access)

In recent years, technological advancements, such as next-generation sequencing and single-cell interrogation techniques, have enriched our understanding in tumor heterogeneity. By dissecting tumors and characterizing clonal lineages, we are better understanding the intricacies of tumor evolution. Tumors are represented by the presence of and dynamic interactions amongst clonal lineages. Each lineage and each cell contributes to tumor dynamics through intrinsic and extrinsic mechanisms, and the variable responses of clones to perturbations in the environment, especially therapeutics, underlie disease progression and relapse. Thus, there exists a pressing need to understand the molecular mechanisms that determine the functional heterogeneity of tumor sub-clones …

Artificial Intron Technology To Generate Conditional Knock-Out Mice, Amber N. Thomas-Gordon

Dissertations and Theses (Open Access)

Genetic engineering has been re-shaped by the invention of new tools in modern biotechnology in a way that offers precision and efficiency in modifying the genome at a single nucleotide level and/or allowing precise control of gene expression. Such gene manipulation brings about significant findings and revelations in comprehending more about embryonic development, cellular and physiological functions, and disease pathology. Current methods used to produce conditional knockouts have limitations on conditional allele placement and modification varies among genes in different organisms. Thus, a system for generating conditional alleles with fidelity remains a challenge. My goal was to examine an approach …

Putative Roles Of Cd200 In The Leukemogenesis And Immune Evasion Of Leukemia Stem Cells, Shelley Herbrich

Dissertations and Theses (Open Access)

Acute myeloid leukemia (AML) stem cells (LSC) are capable of surviving current standard chemotherapy and are the likely source of deadly, relapsed disease. While stem cell transplant serves as proof-of-principle that AML LSCs can be eliminated by the immune system, the translation of existing immunotherapies to AML have been met with limited success. Consequently, understanding and exploiting the unique immune mechanisms of AML LSCs is critical. To identify novel immunotherapeutic targets, we sourced multiple large, publicly available datasets and identified CD200 as a potential stem-cell specific immune checkpoint in AML. We hypothesized that CD200 was a stem-cell specific mechanism of …

Effects Of Penfluridol On Integrin-Fak Signaling And Tumor Cell Killing In Combination With Oncolytic Hsv In Glioblastoma, Mitra Nair

Dissertations and Theses (Open Access)

Integrins are known to play an important role in activating multiple intracellular pathways, one of which is focal adhesion kinase (FAK). Phosphorylation of FAK can lead to the activation of various downstream signaling pathways that can increase tumor cell growth and proliferation, making it an ideal target for cancer therapeutics. Due to the fact that many FAK inhibitors are limited in their penetration of the blood brain barrier, we investigated the use of Penfluridol, an antipsychotic drug known to attenuate integrin expression at a transcriptional level, in combination with oncolytic herpes simplex I virus (oHSV) in a glioblastoma model. We …

Receptor Tyrosine Kinases-Mediated Acquired Parp Inhibitor Resistance In Breast Cancer, Mei-Kuang Chen

Dissertations and Theses (Open Access)

Leveraging compromised DNA damage repair (DDR) pathways commonly found in tumor cells, a classic strategy in cancer therapy is inducing excessive DNA damage to cause cancer cell death. Small molecule poly(ADP-ribose) polymerase (PARP) inhibitors (PARP-is) have been approved for clinical use in treating breast cancer and ovarian cancer patients bearing DDR-deficient tumors with mutations in breast cancer susceptibility genes (BRCA^m). However, accumulating evidences show that both intrinsic and acquired resistances to PARP-is exist in clinic and pre-clinical animal models. Therefore, I developed panels of cells with acquired PARP-is resistance from PARP-is-sensitive triple negative breast cancer (TNBC) cell …

Heterogeneous Nuclear Ribonucleoprotein K (Hnrnp K) Overexpression And Its Interaction With Runx1 Rna In Acute Myeloid Leukemia, Marisa Aitken

Dissertations and Theses (Open Access)

Acute myeloid leukemia (AML) is an often devastating hematologic malignancy with 5-year overall survival lingering near 20%. Acquiring a deeper understanding of molecular underpinnings of leukemogenesis will provide a basis for developing more effective therapeutic strategies for patients with AML.

Here, we identified overexpression of hnRNP K as a recurrent abnormality in a subset (~20%) of AML patients. High levels of this RNA-binding protein associated with inferior clinical outcomes in de novo AML. Thus, to evaluate its putative oncogenic capacity in myeloid disease, we overexpressed hnRNP K in murine hematopoietic stem and progenitor cells isolated from fetal liver cells (FLCs). …

Effect Of Sympathetic Nervous System Mediators On The Tumor Microenvironment Via Small Extracellular Vesicles In Ovarian Cancer, Sujanitha Umamaheswaran, Sujanitha Umamaheswaran

Dissertations and Theses (Open Access)

Effect of sympathetic nervous system mediators on the tumor microenvironment via small extracellular vesicles in ovarian cancer

Sujanitha Umamaheswaran, BTech

Advisor: Anil K. Sood, MD

Background:Psychological stress can promote progression of gynecological malignancies by increasing secretion of sympathetic nervous system (SNS) mediators, namely catecholamines. However, the mechanisms underlying these effects are poorly explored. Here, we examined the effect of stress hormones on small extracellular vesicles (EVs) release in gynecological malignancies and the biological impact of these stress-conditioned EVs on the tumor microenvironment.

Methods:Supernatants were collected from epithelial ovarian cancer cell lines treated with norepinephrine, epinephrine or hydrocortisone. Small EVs were …

Impact Of Epa And Dha Supplementation And 15-Lox-1 Expression On Colitis And Colitis-Associated Colorectal Cancer, Jonathan Jaoude

Dissertations and Theses (Open Access)

Inflammatory bowel disease (IBD) patients not only suffer from colitis but also from increased morbidity and mortality of colitis-associated colorectal cancer (CAC). The enzyme 15-lipoxygenase-1 (15-LOX-1) is crucial to converting omega-3 fatty acid derivatives eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to resolvins, potent anti-inflammatory products. 15-LOX-1 effects on the conversion of EPA and DHA to resolvins that subsequently exert anti-inflammatory and anti-tumorigenic effects have received little attention. To address this knowledge gap, we hypothesize that 15-LOX-1 expression in colonic epithelial cells is essential for resolvin biosynthesis from EPA and DHA to modulate immunophenotype, limit inflammation, promote resolution, and help …

Exosomal Communication By Metastatic Osteosarcoma Cells Modulates Alveolar Macrophages To An M2 Tumor-Promoting Phenotype And Inhibits Tumoricidal Functions, Kerri Wolf

Dissertations and Theses (Open Access)

Osteosarcoma metastasizes to the lung, and there is a link between the predominance of tumor promoting immunosuppressive M2 macrophages in the metastases and poor patient survival. By contrast, M1macrophage predominance correlates with longer survival. M2 macrophages can be induced by various stimuli in the tumor microenvironment, including exosomes, which are 40- to 150-nm vesicles that are involved in intercellular communication and contribute to tumor progression and immune evasion. Recognizing that tumor cells can influence the tumor microenvironment to make it more permissive and because of the link between M2 dominance and curtailed patient survival, we evaluated the effect of …

Understanding Intercellular Signaling During Lung Injury-Repair, Margo Patricia Cain

Dissertations and Theses (Open Access)

The mammalian lung is a complex system of specialized cell types with precise spatial organization designed to cooperate to perform gas exchange. These cell types together coordinate organ development, homeostasis, and repair after injury through signals either presented or secreted, known as ligands, to be received by receptors on the surface of another, or in some cases, the same cell. The alveolar region of the lung, the primary region of gas exchange, responds to various types of injuries with different lung repair mechanisms. In order to explore how the various cell types in the lung communicate to drive tissue repair …

10th Annual Postdoctoral Science Symposium, University Of Texas Md Anderson Cancer Center Postdoctoral Association

Annual Postdoctoral Science Symposium Abstracts

The Annual Postdoctoral Science Symposium (APSS) was initiated on August 4, 2011, by the MD Anderson Postdoctoral Association to provide a platform for talented postdoctoral fellows throughout the Texas Medical Center to present their work to a wider audience.

APSS is a scientific symposium organized by postdoctoral fellows from The University of Texas MD Anderson Cancer Center that welcomes submissions and presentations from postdoctoral fellows from all Texas Medical Center affiliated institutions and other Houston area institutions. The APSS provides a professional venue for postdoctoral scientists to develop, clarify and refine their research as result of formal reviews and critiques …

A Novel Switch-Like Function Of Delta-Catenin In Dendrite Development, Ryan Baumert

Dissertations and Theses (Open Access)

The formation of neuronal networks in the brain is tightly regulated, and dependent on the morphology of dendrites, the branch-like signal-receiving structures extending from neurons. Disruptions in dendrite development, or dendritogenesis, can lead to the atypical neuronal connectivity associated with multiple neurodevelopmental diseases. My research addresses molecular processes that underlie dendritogenesis via analysis of a pair of novel interactions involving the protein delta-catenin.

In neurons, delta-catenin localizes to dendrites and synapses, where it functions in their development and maintenance. Structurally, delta-catenin possesses a central Armadillo domain and a C-terminal PDZ-binding motif. This motif associates with PDZ domain-containing proteins, and is …

Uncovering The Zeb1 Interactome To Identify Novel Regulators Of Metastatic Non-Small Cell Lung Cancer, Roxsan Manshouri

Dissertations and Theses (Open Access)

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death in the United States, due in part to the robust affinity of lung cancer cells to metastasize. Understanding the processes that contribute to metastasis provides promise for the discovery of novel therapeutic targets. Epithelial-tomesenchymal transition (EMT) is a proposed model for the initiation of metastasis. During EMT cell adhesion and polarity is reduced, allowing epithelial cancer cells to dissociate from the primary tumor and invade distant organs. The transcription factor zinc finger E-box-binding homeobox 1 (ZEB1) has been reported to uniquely correlate with NSCLC disease progression and to …