Medical Cell Biology Commons^™

Insights Into P53-Dependent Apoptotic Signaling And Cell Fate Vis-A-Vis Functional Cooperation Among Bcl-Xl, Cytoplasmic P53, And Puma, John C. Fisher

Theses and Dissertations (ETD)

Following DNA damage, nuclear p53 induces the expression of PUMA (p53 upregulated modulator of apoptosis), a BH3‑only protein that binds and inhibits the anti‑apoptotic BCL‑2 repertoire, including BCL‑xL. Structural investigations of PUMA and the BCL‑xL×PUMA BH3 domain complex by X‑ray crystallography and nuclear magnetic resonance (NMR) spectroscopy reveal a novel, PUMA‑induced, domain‑swapped dimerization of BCL‑xL that requires a π‑stacking interaction between PUMA W71 and BCL‑xL H113. PUMA is an intrinsically disordered protein, but upon interaction with BCL‑xL, PUMA W71 and the PUMA BH3 domain residues fold into an alpha helix and subtly remodel BCL‑xL to trigger its dimerization. Wild type …

Novel Insights Into Ubiquitin-Like Protein E1-E2 Interactions, Asad Taherbhoy

Theses and Dissertations (ETD)

Posttranslational modification of macromolecules by ubiquitin-like proteins (UBLs) such as ubiquitin, Sumo and NEDD8 regulate a vast array of processes in the cell. Transfer of UBLs to their target generally occurs by a series of molecular handoffs down an E1‑E2‑E3 cascade. We are interested in understanding how E1‑E2 pairs interact and mediate UBL transfer. To this effect, we studied two E1‑E2 pairs: the Sumo pathway (Sumo utilizes a canonical E1 and E2) and the Atg8 pathway (Atg8 is a UBL involved in autophagy that utilizes a non-canonical E1‑E2 pair).

Sumo conjugation is initiated by the heterodimeric Aos1‑Uba2 E1 enzyme (in …

Mitostatin Is Down-Regulated In Human Prostate Cancer And Suppresses The Invasive Phenotype Of Prostate Cancer Cells., Matteo Fassan, Domenico D'Arca, Juraj Letko, Andrea Vecchione, Marina P Gardiman, Peter Mccue, Bernadette Wildemore, Massimo Rugge, Dolores Shupp-Byrne, Leonard G Gomella, Andrea Morrione, Renato V Iozzo, Raffaele Baffa

Kimmel Cancer Center Faculty Papers

MITOSTATIN, a novel putative tumor suppressor gene induced by decorin overexpression, is expressed in most normal human tissues but is markedly down-regulated in advanced stages of mammary and bladder carcinomas. Mitostatin negatively affects cell growth, induces cell death and regulates the expression and activation levels of Hsp27. In this study, we demonstrated that ectopic expression of Mitostatin in PC3, DU145, and LNCaP prostate cancer cells not only induced a significant reduction in cell growth, but also inhibited migration and invasion. Moreover, Mitostatin inhibited colony formation in soft-agar of PC3 and LNCaP cells as well as tumorigenicity of LNCaP cells in …

The Variable Presentations Of Anaplastic Spindle Cell Squamous Carcinoma Associated With Tall Cell Variant Of Papillary Thyroid Carcinoma., Pallavi P Gopal, Kathleen T Montone, Zubair Baloch, Madalina Tuluc, Virginia Livolsi

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: In 1976, Hawk and Hazard described the tall cell variant (TCV) of papillary thyroid carcinoma (PTC). While the lesions they described had cytologic features of papillary carcinoma, they showed more aggressive behavior with a greater propensity for extrathyroid extension and lymphovascular invasion than classic PTC. In 1991, Bronner and LiVolsi described a series of patients with TCV that progressed to spindle cell squamous carcinoma (SCSC), a unique form of anaplastic thyroid carcinoma. This study describes the variable clinical and pathologic presentations in 31 patients with anaplastic SCSC arising in association with TCV.

METHODS: The surgical pathology archives as well …

A Compact Guide To The Diagnosis And Management Of Neurofibromatosis Type 1, Timothy Beer, David Strayer, Md, Phd

Department of Pathology, Anatomy, and Cell Biology Resident's Posters

Brief Introduction

Neurofibromatosis type 1 (NF-1) is a multisystem neurocutaneous disorder resulting from mutations in the NF-1 gene on chromosome 17 (q11.2). Mutations in NF-1 result in deficient activity of the tumor suppresor protein neurofibromin, allowing for uncontrolled constitutive activity of the proliferative Raspathway in several neural cell types, including neurons, oligodendrocytes, astrocytes and Schawnn cells. Half of NF-1 cases are inherited in autosomal dominant fashion, while half develop sporadically. The syndrome has 100% penetrance but highly variable expressivity. The prevalence of this syndrome is 1/3,000, making it common enough to warrant YOU, the physician, taking a moment to learn …

The Effect Of Training On Motoneuron Survival In Amyotrophic Lateral Sclerosis: Which Motoneuron Type Is Saved?, Sherif M. Elbasiouny, Jenna E. Schuster

Neuroscience, Cell Biology & Physiology Faculty Publications

Amyotrophic lateral sclerosis (ALS) is characterized by selective and progressive degeneration of motoneurons (MNs). Although the etiology of the disease is unknown, glutamate toxicity and reactive oxygen species toxicity have been strongly implicated in ALS pathophysiology, Training exercise has been proposed to provide a beneficial therapy during the early or late stages of ALS; however, some studies showed deleterious effects of exercise on survival in ALS.

Stem Cell Biology And Strategies For Therapeutic Development In Degenerative Diseases And Cancer, Angel A. Alvarez '98

Doctoral Dissertations

Stem cell biology is an exciting field that will lead to significant advancements in science and medicine. We hypothesize that inducing the expression of stem cell genes, using the embryonic stem cell gene nanog, will reprogram cells and dedifferentiate human mesenchymal stem cells into pluripotent stem cells capable of neural differentiation. The aims of initial studies are as follows:

Aim 1: Demonstrate that forced expression of the embryonic stem cell gene nanog induces changes in human mesenchymal stem cells to an embryonic stem cell-like phenotype.

Aim 2: Demonstrate that induced expression of nanog up-regulates the expression of multiple embryonic stem …

Mir-21 Induced Angiogenesis Through Akt And Erk Activation And Hif-1Α Expression., Ling-Zhi Liu, Chongyong Li, Qi Chen, Yi Jing, Richard Carpenter, Yue Jiang, Hsiang-Fu Kung, Lihui Lai, Bing-Hua Jiang

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

MicroRNAs (miRNAs) are endogenous, small noncoding RNAs that play important roles in various cellular functions and tumor development. Recent studies have indicated that miR-21 is one of the important miRNAs associated with tumor growth and metastasis, but the role and molecular mechanism of miR-21 in regulating tumor angiogenesis remain to be elucidated. In this study, miR-21 was overexpressed by transfecting pre-miR-21 into human prostate cancer cells and tumor angiogenesis was assayed using chicken chorioallantoic membrane (CAM). We found that overexpression of miR-21 in DU145 cells increased the expression of HIF-1α and VEGF, and induced tumor angiogenesis. AKT and extracellular regulated …

Prognostic Significance Of High-Grade Dysplasia In Colorectal Adenomas., A D Toll, D Fabius, T Hyslop, E Pequignot, A J Dimarino, A Infantolino, J P Palazzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Aim  Colonoscopy to detect and remove polyps has contributed to a reduction in colorectal carcinoma. Three-year follow up is recommended for patients considered to be at high risk (at least three adenomas, adenoma ≥ 1 cm, villous or high-grade features). Our study focused on patients diagnosed with high-grade dysplasia with regard to initial management and follow up. Method  A search of patients who had had endoscopic removal of a high-grade adenoma was carried out. Patients with the following were excluded: follow up of < 1 year, polyposis syndromes, prior colon cancer and a diagnosis of adenocarcinoma within 6 months following initial diagnosis. Results  Eighty-three patients treated between 1999 and 2007 for high-grade dysplasia (HGD) in a colorectal adenoma were identified. Over a median follow-up period of 4 years, 53 (64%) developed further adenomatous polyps. Among these, 7% had an adenoma with HGD or an adenocarcinoma. In all these patients, the initial high-grade adenoma was > 1 cm in diameter. Initial follow-up colonoscopy was performed on average 7 months following the initial diagnosis. …

Effects Of Influenza Viral Infection On The Cellular Sumoylation System, Joshua Ortiz^, Jason Chacon, German Rosas- Acosta*

COURI Symposium Abstracts, Spring 2011

The tendency of influenza strains to mutate rapidly, changing their antigenic makeup between consecutive seasons and allowing them to jump over the genetic barriers that limit their host range, imposes the risk for the influx of highly pathogenic viral strains into humans. Current available anti-influenza drugs target structural components of the virus and consequently, resistant viral strains arise due to point mutations that render the drugs ineffective. SUMOylation, the reversible post-translational attachment of a SUMO (Small Ubiquitin-like MOdifier) molecule to its target proteins, regulates numerous biological processes. Our studies have shown that some influenza viral proteins are SUMOylated during infection, …

Aging Enhances Serum Cytokine Response But Not Task-Induced Grip Strength Declines In A Rat Model Of Work-Related Musculoskeletal Disorders., Dong L Xin, Michelle Y Harris, Christine K Wade, Mamta Amin, Ann E Barr, Mary F Barbe

Department of Physical Therapy Faculty Papers

BACKGROUND: We previously reported early tissue injury, increased serum and tissue inflammatory cytokines and decreased grip in young rats performing a moderate demand repetitive task. The tissue cytokine response was transient, the serum response and decreased grip were still evident by 8 weeks. Thus, here, we examined their levels at 12 weeks in young rats. Since aging is known to enhance serum cytokine levels, we also examined aged rats.

METHODS: Aged and young rats, 14 mo and 2.5 mo of age at onset, respectfully, were trained 15 min/day for 4 weeks, and then performed a high repetition, low force (HRLF) …

Chloroquine Treatment Of Arpe-19 Cells Leads To Lysosome Dilation And Intracellular Lipid Accumulation: Possible Implications Of Lysosomal Dysfunction In Macular Degeneration, Patrick M. Chen, Zoë J. Gombart, Jeff W. Chen

Dartmouth Scholarship

Age-related macular degeneration (AMD) is the leading cause of vision loss in elderly people over 60. The pathogenesis is still unclear. It has been suggested that lysosomal stress may lead to drusen formation, a biomarker of AMD. In this study, ARPE-19 cells were treated with chloroquine to inhibit lysosomal function. Chloroquine-treated ARPE-19 cells demonstrate a marked increase in vacuolation and dense intracellular debris. These are identified as chloroquine-dilated lysosomes and lipid bodies with LAMP-2 and LipidTOX co-localization, respectively. Dilation is an indicator of lysosomal dysfunction. Chloroquine disrupts uptake of exogenously applied rhodamine-labeled dextran by these cells. This suggests a disruption …

Correlation Of P16ink4a Expression And Hpv Copy Number With Cellular Ftir Spectroscopic Signatures Of Cervical Cancer Cells, Kamila Ostrowska, Amaya Garcia, Aidan Meade, Alison Malkin, Ifeoluwapo Okewumi, John O’Leary, Cara Martin, Hugh Byrne, Fiona Lyng

Articles

Cervical cancer, a potentially preventable disease, has its main aetiology in infection by high risk human papillomavirus (HR-HPV). Approaches to improving cervical cancer screening and diagnostic methodologies include molecular biological analysis, targeting of biomarker proteins, but also exploration and implementation of new techniques such as vibrational spectroscopy. This study correlates the biomarker protein p16^INK4A expression levels dependent on HPV copy number with the infrared absorption spectral signatures of the cervical cancer cell lines, HPV negative C33A, HPV-16 positive SiHa and CaSki and HPV-18 positive HeLa. Confocal fluorescence microscopy demonstrated that p16^INK4A is expressed in all investigated cell lines …

Activation Of The Basolateral Membrane Cl- Conductance Essential For Electrogenic K+ Secretion Suppresses Electrogenic Cl- Secretion, Quanhua He, Susan T. Halm, Jin Zhang, Dan R. Halm

Neuroscience, Cell Biology & Physiology Faculty Publications

Adrenaline activates transient Cl^--secretion and sustained K⁺-secretion across isolated distal colonic mucosa of guinea pig. The Ca⁺⁺-activated Cl^- channel inhibitor CaCCinh-A01 [30μM] significantly reduced electrogenic K⁺-secretion, detected as short-circuit current (I_sc). This inhibition supported the cell model for K⁺-secretion in which basolateral membrane Cl^- channels provide an exit pathway for Cl^- entering the cell via Na⁺/K⁺/2Cl^--cotransporters. CaCCinh-A01 inhibited both I_sc and transepithelial conductance in a concentration dependent manner, IC₅₀ = 6.3 μM. GlyH-101, another Cl^- channel …

Fus Transgenic Rats Develop The Phenotypes Of Amyotrophic Lateral Sclerosis And Frontotemporal Lobar Degeneration., Cao Huang, Hongxia Zhou, Jianbin Tong, Han Chen, Yong-Jian Liu, Dian Wang, Xiaotao Wei, Xu-Gang Xia

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Fused in Sarcoma (FUS) proteinopathy is a feature of frontotemporal lobar dementia (FTLD), and mutation of the fus gene segregates with FTLD and amyotrophic lateral sclerosis (ALS). To study the consequences of mutation in the fus gene, we created transgenic rats expressing the human fus gene with or without mutation. Overexpression of a mutant (R521C substitution), but not normal, human FUS induced progressive paralysis resembling ALS. Mutant FUS transgenic rats developed progressive paralysis secondary to degeneration of motor axons and displayed a substantial loss of neurons in the cortex and hippocampus. This neuronal loss was accompanied by ubiquitin aggregation and …

Expression Of Aldehyde Dehydrogenase In Dysplastic Lesions Arising From Inflammatory Bowel Disease, Adam D. Toll, Bruce M. Boman, Juan P. Palazzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Conclusion: Our study demonstrates ALDH1 is significantly expressed in dysplatic lesions arising from IBD. ALDH1-expression in cancer stem cells suggest an important causative role in the progression to cancer in IBD. Although we found high sensitivity for dysplasia, the specificity was poor. In addition to neoplasia, ALDH1-expressing stem cells proliferate in response to chronic inflammation, accounting for the cases of inflammatory atypia with positive ALDHI1 expression.

Prolactin-Induced Mouse Mammary Carcinomas Model Estrogen Resistant Luminal Breast Cancer., Lisa M Arendt, Debra E Rugowski, Tara A Grafwallner-Huseth, Maria Jose Garcia-Barchino, Hallgeir Rui, Linda A Schuler

Kimmel Cancer Center Faculty Papers

INTRODUCTION: Tumors that express estrogen receptor alpha (ERα+) comprise 75% of breast cancers in women. While treatments directed against this receptor have successfully lowered mortality rates, many primary tumors initially or later exhibit resistance. The paucity of murine models of this "luminal" tumor subtype has hindered studies of factors that promote their pathogenesis and modulate responsiveness to estrogen-directed therapeutics. Since epidemiologic studies closely link prolactin and the development of ERα+ tumors in women, we examined characteristics of the aggressive ERα+ and ERα- carcinomas which develop in response to mammary prolactin in a murine transgenic model (neu-related lipocalin- prolactin (NRL-PRL)). To …

Evidence-Based Genomic Diagnosis Characterized Chromosomal And Cryptic Imbalances In 30 Elderly Patients With Myelodysplastic Syndrome And Acute Myeloid Leukemia., Renu Bajaj, Fang Xu, Bixia Xiang, Katherine Wilcox, Autumn J Diadamo, Rachana Kumar, Alexandra Pietraszkiewicz, Stephanie Halene, Peining Li

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: To evaluate the clinical validity of genome-wide oligonucleotide array comparative genomic hybridization (aCGH) for detecting somatic abnormalities, we have applied this genomic analysis to 30 cases (13 MDS and 17 AML) with clonal chromosomal abnormalities detected in more than 50% of analyzed metaphase cells.

RESULTS: The aCGH detected all numerical chromosomal gains and losses from the mainline clones and 113 copy number alterations (CNAs) ranging from 0.257 to 102.519 megabases (Mb). Clinically significant recurrent deletions of 5q (involving the RPS14 gene), 12p12.3 (ETV6 gene), 17p13 (TP53 gene), 17q11.2 (NF1 gene) and 20q, double minutes containing the MYC gene and …

Effect Of Aging On Cellular Mechanotransduction, Miaozong Wu, Jacqueline Fannin, Kevin M. Rice, Bin Wang, Eric R. Blough

MIIR Faculty Research

Aging is becoming a critical heath care issue and a burgeoning economic burden on society. Mechanotransduction is the ability of the cell to sense, process, and respond to mechanical stimuli and is an important regulator of physiologic function that has been found to play a role in regulating gene expression, protein synthesis, cell differentiation, tissue growth, and most recently, the pathophysiology of disease. Here we will review some of the recent findings of this field and attempt, where possible, to present changes in mechanotransduction that are associated with the aging process in several selected physiological systems, including musculoskeletal, cardiovascular, neuronal, …

Identification Of Genes Involved In Hematopoietic Stem Cell Differentiation And Leukemia Differentiation And Leukemia, Jasjeet Bhullar

Theses, Dissertations and Capstones

Hematopoiesis is maintained by a proper balance between self renewal and multipotent differentiation of the hematopoietic stem cells (HSC). Acute myelogenous leukemia (AML) is characterized by the blockage in the differentiation of HSC, while self renewal and proliferation is preserved. It is important to understand the mechanisms involved in the inhibition of hematopoietic differentiation and maintenance of the HSC state in order to develop better therapies for AML. In these studies I have explored the role of Hsp90, omega-3 fatty acids and YB-1 in hematopoietic differentiation. EML, a hematopoietic precursor cell line, was used as a model for the hematopoietic …