Life Sciences Commons^™

Mimicking The Effect Of Prolactin On Stat3/Stat5 Activity In Breast Cancer, Jennifer N. Barbuto, Sarah R. Walker

Honors Theses and Capstones

Signal transducers and activators of transcription (STAT) 3 and 5 are commonly constitutively activated in breast cancer. STAT5 can outcompete STAT3 and reduce cell proliferation and metastasis. STAT5 activation is stimulated by prolactin, a natural hormone that can be harmful at high levels. The aim of this study is to identify some possible previously developed drugs that mimic the effect of prolactin and STAT5 without the added risk in MDA-MB231 breast cancer cells. Using the CLUE database query app and STAT5 up- and downregulation signatures, three drugs (X, K, and M) were chosen based on their similarity in signatures to …

Bypassing The Blood-Brain Barrier: A Physical And Pharmacological Approach For The Treatment Of Metastatic Brain Tumors, Samuel A. Sprowls

Graduate Theses, Dissertations, and Problem Reports

This dissertation (a) provided an in depth literature review of methods to disrupt the BBB/BTB and improve therapeutic distribution to brain tumors, (b) evaluated the use of azacitidine as a single agent therapy for the treatment of brain metastasis of breast cancer and a potential molecular mechanism by which brain tropic cells are sensitized to hypomethylating agents, (c) determined the impact cannabidiol has on P-glycoprotein mediated efflux at the blood-brain barrier and its potential for use as a single agent treatment for metastatic brain tumors, (d) developed a preclinical radiation therapy protocol for use in small animals and in vitro …

Rho Gtpases: Big Players In Breast Cancer Initiation, Metastasis And Therapeutic Responses, Brock Humphries, Zhishan Wang, Chengfeng Yang

Toxicology and Cancer Biology Faculty Publications

Rho GTPases, a family of the Ras GTPase superfamily, are key regulators of the actin cytoskeleton. They were originally thought to primarily affect cell migration and invasion; however, recent advances in our understanding of the biology and function of Rho GTPases have demonstrated their diverse roles within the cell, including membrane trafficking, gene transcription, migration, invasion, adhesion, survival and growth. As these processes are critically involved in cancer initiation, metastasis and therapeutic responses, it is not surprising that studies have demonstrated important roles of Rho GTPases in cancer. Although the majority of data indicates an oncogenic role of Rho GTPases, …

A Review On Recent Advancements In Diagnosis And Classification Of Cancers Using Artificial Intelligence, Priyanka Ramesh, Ramanathan Karuppasamy, Shanthi Veerappapillai

BioMedicine

Artificial intelligence has illustrated drastic changes in radiology and medical imaging techniques which in turn led to tremendous changes in screening patterns. In particular, advancements in these techniques led to the development of computer aided detection (CAD) strategy. These approaches provided highly accurate diagnostic reports which served as a “second-opinion” to the radiologists. However, with significant advancements in artificial intelligence strategy, the diagnostic and classifying capabilities of CAD system are meeting the levels of radiologists and clinicians. Thus, it shifts the CAD system from second opinion approach to a high utility tool. This article reviews the strategies and algorithms developed …

Novel Role For The Golgi Membrane Protein Tmem165 In Control Of Migration And Invasion For Breast Carcinoma, Pavitra Murali, Blake P. Johnson, Zhongpeng Lu, Leslie Climer, Danielle A. Scott, Francois Foulquier, Gabriela Oprea-Ilies, Vladimir Lupashin, Richard R. Drake, Karen L. Abbott

Articles

The TMEM165 gene encodes for a multiple pass membrane protein localized in the Golgi that has been linked to congenital disorders of glycosylation. The TMEM165 protein is a putative ion transporter that regulates H+/Ca++/Mn++ homeostasis and pH in the Golgi. Previously, we identified TMEM165 as a potential biomarker for breast carcinoma in a glycoproteomic study using late stage invasive ductal carcinoma tissues with patient-matched adjacent normal tissues. The TMEM165 protein was not detected in non-malignant matched breast tissues and was detected in invasive ductal breast carcinoma tissues by mass spectrometry. Our hypothesis is that the TMEM165 protein confers a growth …

Breast Cancer Sub-Clones That Metastasize To Lung And Bone Exhibit Different Metabolic Preferences, Mollie Merrell

Honors Theses

Metastasis is responsible for the majority of cancer related deaths. In breast cancer the lungs and bones are the major sites for metastasis. Previous studies used the metastatic aggressive MDA-MB-231 breast cancer line to isolate sub-clones that preferentially invade the lungs (LM line) or bones (BoM line). While genes associated with the tissue specific metastasis have been identified, it is unknown if metabolic adaptations contribute to the growth of the LM and BoM lines in their respective organs. The goal of this study was to test the hypothesis that the LM and BoM lines exhibit differences in glucose and glutamine …

Hsp47 Promotes Cancer Metastasis By Enhancing Collagen-Dependent Cancer Cell-Platelet Interaction, Gaofeng Xiong, Jie Chen, Guoying Zhang, Shike Wang, Kunito Kawasaki, Jieqing Zhu, Yan Zhang, Kazuhiro Nagata, Zhenyu Li, Binhua P. Zhou, Ren Xu

Markey Cancer Center Faculty Publications

Increased expression of extracellular matrix (ECM) proteins in circulating tumor cells (CTCs) suggests potential function of cancer cell-produced ECM in initiation of cancer cell colonization. Here, we showed that collagen and heat shock protein 47 (Hsp47), a chaperone facilitating collagen secretion and deposition, were highly expressed during the epithelial-mesenchymal transition (EMT) and in CTCs. Hsp47 expression induced mesenchymal phenotypes in mammary epithelial cells (MECs), enhanced platelet recruitment, and promoted lung retention and colonization of cancer cells. Platelet depletion in vivo abolished Hsp47-induced cancer cell retention in the lung, suggesting that Hsp47 promotes cancer cell colonization by enhancing cancer cell–platelet interaction. …

Efficacy And Safety Of Everolimus-Exemestane Combination In Breast Cancer Patients, Siba Jneid, S. Hlais, George Chahine, Doua Issa, Thouraya Domyati

BAU Journal - Health and Wellbeing

Breast cancer is the second leading cause of cancer death in women worldwide. In Lebanon, hormone positive patients resistant to endocrine treatments account for most of the cases. These two facts directed the attention to evaluate everolimus-exemestane use in hormonal receptor positive metastatic breast cancer patients, in Lebanon. A multi-center, observational, retrospective cohort study was carried out by screening 69 metastatic breast cancer patient’s files in order to determine the progression free survival (PFS), overall survival (OS) and side effects of everolimus. This study revealed that across different therapy lines, the median PFS for patients on everolimus-exemestane combination was 5.87 …

Obesity Promotes Cooperation Of Cancer Stem-Like Cells And Macrophages To Enhance Mammary Tumor Angiogenesis, Lauren E. Hillers-Ziemer, Rachel Q. Mcmahon, Margaret Hietpas, Gretchen Paderta, Jennelle Lebeau, Jessica Mccready, Lisa M. Arendt

Biological and Physical Sciences Department Faculty Works

Obesity is correlated with worsened prognosis and treatment resistance in breast cancer. Macrophage-targeted therapies are currently in clinical trials, however, little is known about how obesity may impact treatment efficacy. Within breast adipose tissue, obesity leads to chronic, macrophage-driven inflammation, suggesting that obese breast cancer patients may benefit from these therapies. Using a high fat diet model of obesity, we orthotopically transplanted cancer cell lines into the mammary glands of obese and lean mice. We quantified changes in tumor invasiveness, angiogenesis and metastasis, and examined the efficacy of macrophage depletion to diminish tumor progression in obese and lean mice. Mammary …

Optimisation Of Estrogen Receptor Subtype-Selectivity Of A 4-Aryl-4h-Chromene Scaffold Previously Identified By Virtual Screening, Miriam Carr, Andrew Knox, Daniel Nevin, Niamh O'Boyle, Shu Wang, Billy Egan, Thomas Mccabe, Brendan Twamley, Daniela Zisterer, David Lloyd, Mary Meegan

Articles

4-Aryl-4H-Chromene derivatives have been previously shown to exhibit anti-proliferative, apoptotic and anti-angiogenic activity in a variety of tumor models in vitro and in vivo generally via activation of caspases through inhibition of tubulin polymerisation. We have previously identified by Virtual Screening (VS) a 4-aryl-4H-chromene scaffold, of which two examples were shown to bind Estrogen Receptor α and β with low nanomolar affinity and <20-fold selectivity for α over β and low micromolar anti-proliferative activity in the MCF-7 cell line. Thus, using the 4-aryl-4H-chromene scaffold as a starting point, a series of compounds with a range of basic arylethers at C-4 and modifications at the C3-ester substituent of the benzopyran ring were synthesised, producing some potent ER antagonists in the MCF-7 cell line which were highly selective for ERα (compound 35; 350-fold selectivity) or ERβ (compound 42; 170-fold selectivity).

A Systematic Comparison Of Lipopolymers For Sirna Delivery To Multiple Breast Cancer Cell Lines: In Vitro Studies, Hamidreza Montazeri Aliabadi, Remant Bahadur Kc, Emira Bousoik, Ashley Barbarino, Bindu Thapa, Melissa Coyle, Parvin Mahdipoor, Hasan Uludağ

Pharmacy Faculty Articles and Research

Small interfering RNA (siRNA) therapy is a promising approach for treatment of a wide range of cancers, including breast cancers that display variable phenotypic features. To explore the general utility of siRNA therapy to control aberrant expression of genes in breast cancer, we conducted a detailed analysis of siRNA delivery and silencing response in vitro in 6 separate breast cancer cell models (MDA-MB-231, MDA-MB-231-KRas-CRM, MCF-7, AU565, MDA-MB-435 and MDA-MB-468 cells). Using lipopolymers for siRNA complexation and delivery, we found a large variation in siRNA delivery efficiency depending on the specific lipopolymer used for siRNA complexation and delivery. Some lipopolymers were …

Markov Decision Process Approach To Strategize National Breast Cancer Screening Policy In Data-Limited Settings, Vijeta Deshpande

Masters Theses

Early diagnosis is a promising strategy to reduce premature mortalities and for optimal use of resources. But the absence of mathematical models specific to the data settings in LMIC’s impedes the construction of economic analysis necessary for decision-makers in the development of cancer control programs. This thesis presents a new methodology for parameterizing the natural history model of breast cancer based on data availabilities in low and middle income countries, and formulation of a control optimization problem to find the optimal screening schedule for mammography screening, solved using dynamic programming. As harms and benefits are known to increase with the …

Heterogeneity And Plasticity Of Human Breast Cancer Cells In Response To Molecularly-Targeted Drugs, Emira Bousoik, Ramina Nabiee, Farideh Amirrad, Ashley Nichols, Rebecca Witt, Parvin Mahdipoor, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

Non-responsive subpopulation of tumor cells, and acquired resistance in initially responsive cells are major challenges for cancer therapy with molecularly-targeted drugs. While point mutations are considered the major contributing factor to acquired resistance, in this study we explored the role of heterogeneity and plasticity of selected human breast cancer cell lines (MDA-MB-231, MDA-MB-468, and AU565) in their initial and adjusted response, respectively, to ruxolitinib, everolimus, and erlotinib. After determination of lethal concentration for 50% cell death (LC50), cells were exposed to selected drugs using three different approaches: single exposure to 4 × LC50 and collection of surviving cells, multiple exposures …

Gcn5 Loss Impacts Myc-Driven Cancer In Mice And Human Cells, Aimee Farria

Dissertations & Theses (Open Access)

GCN5 is the catalytic subunit in the acetyltransferase module of SAGA and ATAC, multiprotein complexes involved in the modification of histone and nonhistone proteins. GCN5 is most recognized as a co-activator of gene transcription. The SAGA complex is recruited to chromatin by transcription factors such as MYC and E2F1 where GCN5 acetylates H3K9 leading to a more open and accessible chromatin structure. Previous research has demonstrated that GCN5 also acetylates MYC, a protein that amplifies the expression of cancer-promoting genes and is frequently dysregulated in cancer, increasing its stability. Our lab has found there is a significant overlap in the …

Microrna Regulation Of Epigenetic Modifiers In Breast Cancer, Brock Humphries, Zhishan Wang, Chengfeng Yang

Toxicology and Cancer Biology Faculty Publications

Epigenetics refers to the heritable changes in gene expression without a change in the DNA sequence itself. Two of these major changes include aberrant DNA methylation as well as changes to histone modification patterns. Alterations to the epigenome can drive expression of oncogenes and suppression of tumor suppressors, resulting in tumorigenesis and cancer progression. In addition to modifications of the epigenome, microRNA (miRNA) dysregulation is also a hallmark for cancer initiation and metastasis. Advances in our understanding of cancer biology demonstrate that alterations in the epigenome are not only a major cause of miRNA dysregulation in cancer, but that miRNAs …

Amphiphilic Peptides For Efficient Sirna Delivery, Saghar Mozaffari, Emira Bousoik, Farideh Amirrad, Robert Lamboy, Melissa Coyle, Ryley Hall, Abdulaziz Alasmari, Parvin Mahdipoor, Keykavous Parang, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

A number of amphiphilic cyclic peptides—[FR]4, [WR]5, and [WK]5—containing hydrophobic and positively-charged amino acids were synthesized by Fmoc/tBu solid-phase peptide methods and evaluated for their efficiency in intracellular delivery of siRNA to triple-negative breast cancer cell lines, MDA-MB-231 and MDA-MB-468, in the presence and absence of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE). Among the peptides, [WR]5, which contains alternate tryptophan (W) and arginine (R) residues, was found to be the most efficient in the delivery of siRNA by improving the delivery by more than 3-fold when compared to other synthesized cyclic peptides that were not efficient. The data also showed that co-formulation of [WR]5 …

Induction Of Ampk Activation By N,N'-Diarylurea Fnd-4b Decreases Growth And Increases Apoptosis In Triple Negative And Estrogen-Receptor Positive Breast Cancers, Jeremy Johnson, Piotr G. Rychahou, Vitaliy M. Sviripa, Heidi L. Weiss, Chunming Liu, David S. Watt, B. Mark Evers

Markey Cancer Center Faculty Publications

Purpose

Triple negative breast cancer (TNBC) is the most lethal and aggressive subtype of breast cancer. AMP-activated protein kinase (AMPK) is a major energy regulator that suppresses tumor growth, and 1-(3-chloro-4-((trifluoromethyl)thio)phenyl)-3-(4-(trifluoromethoxy)phenyl)urea (FND-4b) is a novel AMPK activator that inhibits growth and induces apoptosis in colon cancer. The purpose of this project was to test the effects of FND-4b on AMPK activation, proliferation, and apoptosis in breast cancer with a particular emphasis on TNBC.

Materials and methods

(i) Estrogen-receptor positive breast cancer (ER+BC; MCF-7, and T-47D), TNBC (MDA-MB-231 and HCC-1806), and breast cancer stem cells were treated with FND-4b for 24h. …

Clinical Features, Survival And Prognostic Factors Of Glycogen-Rich Clear Cell Carcinoma (Grcc) Of The Breast In The U.S. Population, Zhengqiu Zhou, Connor J. Kinslow, Hanina Hibshoosh, Hua Guo, Simon K. Cheng, Chunyan He, Matthew S. Gentry, Ramon C. Sun

Molecular and Cellular Biochemistry Faculty Publications

The World Health Organization (WHO) defines glycogen-rich clear cell carcinoma (GRCC) of the breast as a carcinoma with glycogen accumulation in more than 90% of its tumor cells. Due to the rarity of this disease, its reported survival and clinical associations have been inconsistent due to reliance on case reports and limited case series. As a result, the prognostic implication of this cancer subtype remains unclear. Using the U.S. Surveillance, Epidemiology, and End Results (SEER) program database, we compared the incidence, demographics and prognostic factors of 155 cases of GRCC of the breast to 1,251,584 cases of other (non-GRCC) breast …

Star-Related Lipid Transfer Protein 10 (Stard10): A Novel Key Player In Alcohol-Induced Breast Cancer Progression, Andrea Floris, Jia Luo, Jacqueline A. Frank, Jennifer Zhou, Sandro Orrù, Michela Biancolella, Sabina Pucci, Augusto Orlandi, Paolo Campagna, Antonella Balzano, Komal Ramani, Maria Lauda Tomasi

Pharmacology and Nutritional Sciences Faculty Publications

Background: Ethanol abuse promotes breast cancer development, metastasis and recurrence stimulating mammary tumorigenesis by mechanisms that remain unclear. Normally, 35% of breast cancer is Erb-B2 Receptor Tyrosine Kinase 2 (ERBB2)-positive that predisposes to poor prognosis and relapse, while ethanol drinking leads to invasion of their ERBB2 positive cells triggering the phosphorylation status of mitogen-activated protein kinase. StAR-related lipid transfer protein 10 (STARD10) is a lipid transporter of phosphatidylcholine (PC) and phosphatidylethanolamine (PE); changes on membrane composition of PC and PE occur before the morphological tumorigenic events. Interestingly, STARD10 has been described to be highly expressed in 35–40% of ERBB2-positive breast …

Development Of Multifunctional Overhauser-Enhanced Magnetic Rresonance Imaging For Concurrent In Vivo Mapping Of Tumor Interstitial Oxygenation, Acidosis And Inorganic Phosphate Concentration, Artem A. Gorodetskii, Timothy D. Eubank, Benoit Driesschaert, Martin Poncelet, Emily Ellis, Valery V. Khramtsov, Andrey A. Bobko

Faculty & Staff Scholarship

Tumor oxygenation (pO2), acidosis (pH) and interstitial inorganic phosphate concentration (Pi) are important parameters of the malignant behavior of cancer. A noninvasive procedure that enables visualization of these parameters may provide unique information about mechanisms of tumor pathophysiology and provide clues to new treatment targets. In this research, we present a multiparametric imaging method allowing for concurrent mapping of pH, spin probe concentration, pO2, and Pi using a single contrast agent and Overhauser-enhanced magnetic resonance imaging technique. The developed approach was applied to concurrent multifunctional imaging in phantom samples and in vivo in a mouse model of …

Uncovering The Signaling Landscape Controlling Breast Cancer Cell Migration Identifies Novel Metastasis Driver Genes, Esmee Koedoot, Michiel Fokkelman, Vasiliki-Maria Rogkoti, Marcel Smid, Iris Van De Sandt, Hans De Bont, Chantal Pont, Janna E. Klip, Steven Wink, Mieke A. Timmermans, Erik A. C. Wiemer, Peter Stoilov, John A. Foekens, Sylvia E. Le Dévédec, John W. M. Martens, Bob Van De Water

Faculty & Staff Scholarship

Ttriple-negative breast cancer (TNBC) is an aggressive and highly metastatic breast cancer subtype. Enhanced TNBC cell motility is a prerequisite of TNBC cell dissemination. Here, we apply an imaging-based RNAi phenotypic cell migration screen using two highly motile TNBC cell lines (Hs578T and MDA-MB-231) to provide a repository of signaling determinants that functionally drive TNBC cell motility. We have screened ~4,200 target genes individually and discovered 133 and 113 migratory modulators of Hs578T and MDA-MB-231, respectively, which are linked to signaling networks predictive for breast cancer progression. The splicing factors PRPF4B and BUD31 and the transcription factor BPTF are essential …

Embryonic Stem Cell-Derived Exosomes Increase The Antiproliferative Activity Of Doxorubicin In Breast Cancer, Alexander M. Hirsch

Theses and Dissertations

The field of cancer research has grown immensely in recent decades and has led to a better understanding of the causes of the disease, as well as greatly improved treatment for various types of cancers, especially breast cancer. One of the most effective treatments involves the chemotherapeutic drug doxorubicin (DOX). DOX is an effective tool against all types of breast cancer, especially against triple negative breast cancer. However, DOX causes adverse side effects that include damage to the heart and skeletal muscle, particularly above specific cumulative doses. Recent evidence suggests that embryonic stem cell-derived (ES) exosomes, nanoscale extracellular vesicles that …

Effectiveness And Mechanism Of Action Of Modified Porphyrins For Photodynamic Therapy Of Triple Negative Breast Cancer Cells, Hannah Brandon

Honors Theses

Triple negative breast cancer (TNBC) is a particularly aggressive form of breast cancer that lacks the three molecules typically targeted for treatment. Standard treatment methods leave much to be desired--the rates of metastasis and recurrence are high and the prognosis for most patients with TNBC is poor. One potential treatment for TNBC is photodynamic therapy (PDT), which uses compounds called photosensitizers that are taken up by all tissues in the body. The tumor is exposed to light, activating the photosensitizer and creating reactive oxygen species that cause cell death. This method is relatively pain-free, effective, and does not harm cells …

Vitamin D Receptor Gene Polymorphisms Knowledge And Breast Cancer In Texas, Ejike Roland Egwuekwe

Walden Dissertations and Doctoral Studies

Breast cancer is a world health problem and is a leading cause of cancer-related death among women in the United States. However, breast cancer risks were reported to be reduced through exposure to Vitamin D through its Receptors identified as the p53 target gene. The purpose of this study was to assess the associations between VDR gene polymorphisms knowledge/awareness and decisions to reduce breast cancer risks and likelihood of mammogram screening among women in Texas. Data from survey were used. Roy adaptation model was the theoretical framework that guided this quasi- experimental, quantitative research. The dependent variables were decisions to …

The Role Of Syndecan-1 And Extracellular Vesicles In Breast Cancer Brain Metastasis, Megan R. Sayyad

Theses and Dissertations

Breast cancer metastasizes to the brain in 15-30% of all breast cancer cases, and metastasis is the predominant cause of breast cancer-related deaths. Patients with HER2-enriched and triple-negative breast cancers (TNBCs) are more likely to develop brain metastases. While targeted therapies exist for HER2-enriched breast cancers, there are no effective treatments for TNBCs. Thus, a greater understanding of how these cancers spread to the brain is critical. In order to spread to the brain, disseminated breast cancer cells must overcome 2 major steps—crossing the blood-brain barrier (BBB) and survival and successful colonization of the distinctive and mostly cellular brain environment. …

Targeting The Brd4/Foxo3a/Cdk6 Axis Sensitizes Akt Inhibition In Luminal Breast Cancer, Jingyi Liu, Weijie Guo, Zhibing Duan, Lei Zeng, Yadi Wu, Yule Chen, Fang Tai, Yifan Wang, Yiwei Lin, Qiang Zhang, Yanling He, Jiong Deng, Rachel L. Stewart, Chi Wang, Pengnian Charles Lin, Saghi Ghaffari, B. Mark Evers, Suling Liu, Ming-Ming Zhou, Binhua P. Zhou, Jian Shi

Molecular and Cellular Biochemistry Faculty Publications

BRD4 assembles transcriptional machinery at gene super-enhancer regions and governs the expression of genes that are critical for cancer progression. However, it remains unclear whether BRD4-mediated gene transcription is required for tumor cells to develop drug resistance. Our data show that prolonged treatment of luminal breast cancer cells with AKT inhibitors induces FOXO3a dephosphorylation, nuclear translocation, and disrupts its association with SirT6, eventually leading to FOXO3a acetylation as well as BRD4 recognition. Acetylated FOXO3a recognizes the BD2 domain of BRD4, recruits the BRD4/RNAPII complex to the CDK6 gene promoter, and induces its transcription. Pharmacological inhibition of either BRD4/FOXO3a association or …

The Role Of Tumor Suppressor Dear1 In The Acquisition Of Mammary Stem/Progenitor Cell Properties, Uyen Le

Dissertations & Theses (Open Access)

Breast cancer is the most commonly diagnosed cancer in women in America. Ductal carcinoma in situ (DCIS), one of the earliest pre-invasive forms of invasive ductal carcinoma (IDC), has a 30-50% risk of progressing to IDC. Understanding the mechanisms regulating progression from DCIS to IDC would help identify biomarkers to stratify patients at higher risk of progression or metastasis. Cumulative literature suggests the earliest phase of dissemination from the primary tumor is driven by the epithelial-mesenchymal transition (EMT) program. DEAR1 is a tumor suppressor gene which is mutated, undergoes loss of heterozygosity in breast cancer, and is downregulated in DCIS …

Isobavachalcone Sensitizes Cells To E2-Induced Paclitaxel Resistance By Down-Regulating Cd44 Expression In Er+ Breast Cancer Cells, Junfeng Shi, Yi Chen, Wenxing Chen, Cuiju Tang, Honghong Zhang, Yuetong Chen, Xiuwei H. Yang, Zhi Xu, Jingsun Wei, Jinfei Chen

Pharmacology and Nutritional Sciences Faculty Publications

Oestrogen receptor (ER) is expressed in approximately 60%‐70% of human breast cancer. Clinical trials and retrospective analyses have shown that ER‐positive (ER+) tumours are more tolerant to chemotherapeutic drug resistance than ER‐negative (ER−) tumours. In addition, isobavachalcone (IBC) is known as a kind of phytoestrogen with antitumour effect. However, the underlying mechanism of IBC in ER+ breast cancer needs to be elucidated further. Our in vitro experiments showed that IBC could attenuate 17β‐estradiol (E₂)‐induced paclitaxel resistance and that E₂ could stimulate CD44 expression in ER+ breast cancer cells but not in ER− cells. Meanwhile, E₂ could …

Lung-Derived Selectins Interact With Cd44 And Enhance The Migration Of Breast Cancer Cells, Sami U. Khan

Electronic Thesis and Dissertation Repository

The lung is among the deadliest sites of breast cancer metastasis. Previous work from our laboratory demonstrated that aggressive CD44-expressing breast cancer cells preferentially metastasize to the lung in vivo, and observed the presence of multiple CD44-interacting proteins in the lung including E-, L- and P-selectin. We hypothesized that lung-derived selectins promote breast cancer migration and/or growth via interactions with CD44. Using an ex vivo model of the soluble lung-microenvironment, we demonstrate that lung-derived selectins enhance in vitro migration but not proliferation of breast cancer cells. Co-immunoprecipitation experiments reveal that CD44 expressed by breast cancer cells in vitro interacts …

Deciphering The Role Of Human Arylamine N-Acetyltransferase 1 (Nat1) In Breast Cancer Cell Metabolism Using A Systems Biology Approach., Samantha Marie Carlisle

Electronic Theses and Dissertations

Background: Human arylamine N-acetyltransferase 1 (NAT1) is a phase II xenobiotic metabolizing enzyme found in almost all tissues. NAT1 can additionally hydrolyze acetyl-coenzyme A (acetyl-CoA) in the absence of an arylamine substrate. NAT1 expression varies inter-individually and is elevated in several cancers including estrogen receptor positive (ER+) breast cancers. Additionally, multiple studies have shown the knockdown of NAT1, by both small molecule inhibition and siRNA methods, in breast cancer cells leads to decreased invasive ability and proliferation and decreased anchorage-independent colony formation. However, the exact mechanism by which NAT1 expression affects cancer risk and progression remains unclear. Additionally, consequences …