Cell and Developmental Biology Commons^™

Sprouty4 Is A Negative Regulator Of Erk/Mapk Signaling In Breast Cancer And Plays A Role In The Transition From In Situ To Invasive Disease, Ethan Brock

Wayne State University Dissertations

Breast ductal carcinoma in situ (DCIS) is a non-obligate precursor of invasive ductal carcinoma (IDC). It is still unclear which DCIS will become invasive and which will remain indolent. Previous data by our group found that Sprouty4 transcript was differentially expressed between three DCIS cell lines and a non-transformed breast epithelial cell line. Sprouty proteins are important regulators of ERK/MAPK signaling, and have been studied in various cancers. We hypothesized that Sprouty4 is an endogenous inhibitor of ERK/MAPK signaling and that its loss/reduced expression is a mechanism by which DCIS lesions progress toward IDC, including triple-negative disease. Using immunohistochemistry we …

Adipocyte-Induced Inflammation In Prostate Tumor Progression In Bone: Role Of Cxcr2 And Osteopontin, Aimalie Lynnette Hardaway

Wayne State University Dissertations

Abstract

Prostate cancer (PCa) is the second leading cause of cancer-related deaths among men. Evidence suggests that age and obesity, conditions associated with adipocyte accumulation in the bone marrow, are linked to increased risk of developing PCa and progressing to metastatic disease. Studies presented in this dissertation were based on the hypothesis that metastatic progression in bone is a result of a cooperative effort between bone marrow adipocytes, macrophages, osteoclasts, and PCa cells. We specifically focused on two adipocyte-supplied chemokines, CXCL1 and CXCL2, and bone marrow macrophage-secreted osteopontin as key drivers of pro-inflammatory environment in the bone marrow and important …

Combating Resistance To Epidermal Growth Factor Recpetor Inhibitors In Triple Negative Breast Cancer, Julie Marie Madden

Wayne State University Dissertations

Triple negative breast cancer (TNBC) patients suffer from a highly malignant and aggressive cancer that lacks an effective targeted therapeutic. Although many TNBCs, both in vitro and in vivo, have increased expression of epidermal growth factor receptor (EGFR), EGFR targeted inhibitors, such as gefitinib (GEF), have yet to demonstrate efficacy. Using mass spectrometry to identify pathways that remain activated in the presence of GEF, we found that components of the mTOR signaling pathway remain phosphorylated. While inhibiting mTOR with temsirolimus (TEM) decreased mTOR signaling, EGFR signaling pathways remained activated and the TNBC cell lines continued to proliferate. However, dual treatment …

Resistance Of Human Cytomegalovirus To Cyclopropavir Maps To A Base Pair Deletion In The Open Reading Frame Of Ul97, Brian G. Gentry, Laura E. Vollmer, Ellie D. Hall, Katherine Z. Borysko, Jiri Zemlicka, Jeremy P. Kamil, John C. Drach

Oncology Faculty Publications

Human cytomegalovirus (HCMV) is a widespread pathogen in the human population, affecting many immunologically immature and immunocompromised patients, and can result in severe complications, such as interstitial pneumonia and mental retardation. Current chemotherapies for the treatment of HCMV infections include ganciclovir (GCV), foscarnet, and cidofovir. However, the high incidences of adverse effects (neutropenia and nephrotoxicity) limit the use of these drugs. Cyclopropavir (CPV), a guanosine nucleoside analog, is 10-fold more active against HCMV than GCV (50% effective concentrations [EC₅₀s] = 0.46 and 4.1 μM, respectively). We hypothesize that the mechanism of action of CPV is similar to that …

Gambogic Acid Is A Tissue-Specific Proteasome Inhibitor In Vitro And In Vivo, Xiaofen Li, Shouting Liu, Hongbiao Huang, Ningning Liu, Chong Zhao, Siyan Liao, Changshan Yang, Yurong Liu, Canguo Zhao, Shujue Li, Xiaoyu Lu, Chunjiao Liu, Lixia Guan, Kai Zhao, Xiaoqing Shi, Wenbin Song, Ping Zhou, Xiaoxian Dong, Haiping Guo, Guanmei Wen, Change Zhang, Lili Jiang, Ningfang Ma, Bing Li, Shunqing Wang, Huo Tan, Xuejun Wang, Q. Ping Dou, Jinbao Lin

Oncology Faculty Publications

Gambogic acid (GA) is a natural compound derived from Chinese herbs that has been approved by the Chinese Food and Drug Administration for clinical trials in cancer patients; however, its molecular targets have not been thoroughly studied. Here, we report that GA inhibits tumor proteasome activity, with potency comparable to bortezomib but much less toxicity. First, GA acts as a prodrug and only gains proteasome-inhibitory function after being metabolized by intracellular CYP2E1. Second, GA-induced proteasome inhibition is a prerequisite for its cytotoxicity and anticancer effect without off-targets. Finally, because expression of the CYP2E1 gene is very high in tumor tissues …

Activation Of Amp-Activated Protein Kinase By 3,39-Diindolylmethane (Dim) Is Associated With Human Prostate Cancer Cell Death In Vitro And In Vivo, Di Chen, Sanjeev Banerjee, Qiuzhi C. Cui, Dejuan Kong, Fazlul H. Sarkar, Q. Ping Dou

Oncology Faculty Publications

There is a large body of scientific evidence suggesting that 3,39-Diindolylmethane (DIM), a compound derived from the digestion of indole-3-carbinol, which is abundant in cruciferous vegetables, harbors anti-tumor activity in vitro and in vivo. Accumulating evidence suggests that AMP-activated protein kinase (AMPK) plays an essential role in cellular energy homeostasis and tumor development and that targeting AMPK may be a promising therapeutic option for cancer treatment in the clinic. We previously reported that a formulated DIM (BR-DIM; hereafter referred as B-DIM) with higher bioavailability was able to induce apoptosis and inhibit cell growth, angiogenesis, and invasion of prostate cancer cells. …

A Role For Reactive Oxygen Species In Photodynamic Therapy, Michael Price

Wayne State University Dissertations

Photodynamic therapy (PDT) is based on the ability of certain photosensitizing agents to selectively localize in neoplastic cells and their vasculature. Subsequent irradiation at a wavelength corresponding to a photosensitizer absorbance band excites the photosensitizer molecules, leading to energy transfer reactions and fluorescence. It was initially concluded that the phototoxic effect occurred when energy from the excited state of the photosensitizer was transferred to dissolved oxygen to form singlet oxygen. This product has a very brief half-life and will cause cellular damage only in the immediate vicinity of its formation. But an excited-state photosensitizer can also interact with oxygen to …

Hdm2 Small-Molecule Inhibitors For Therapeutic Intervention In B-Cell Lymphoma, Angela Sosin

Wayne State University Dissertations

Lymphomas frequently retain wild-type (wt) p53 function but overexpress HDM2, compromising p53 activity. Therefore, lymphoma is a suitable model for studying therapeutic value of disrupting HDM2-p53 association by small-molecule inhibitors (SMIs). HDM2 SMIs have been developed and are currently under various stages of preclinical and clinical investigation. This study examined various molecular mechanisms associated and biological effects of two different classes of HDM2 SMIs: the spiro-oxindoles (MI-219) and cis-imidazoline (Nutlin-3) in lymphoma cell lines and patient-derived B-lymphoma cells. Surprisingly, results revealed significant quantitative and qualitative differences between these two agents. At the molecular level, effect of Nutlin-3 was generally more …

The Role Of The Sparc Acidic Domain And Egf-Like Module In Glioma Migration, Invasion, And Signaling, Heather M. Mcclung

Wayne State University Dissertations

THE ROLE OF THE SPARC ACIDIC DOMAIN AND EGF-LIKE MODULE IN GLIOMA MIGRATION, INVASION, AND SIGNALING

HEATHER M. MCCLUNG

Advisor: Sandra A. Rempel, Ph.D.

Major: Pharmacology

Degree: Doctor of Philosophy

We have previously shown that Secreted Protein Acidic and Rich in Cysteine (SPARC) is upregulated in all astrocytoma grades and increases tumor cell migration and invasion. It is thought that different domains within the protein may regulate SPARC functions, suggesting domain-specific targeting to inhibit invasion. To enhance our understanding of SPARC-mediated invasion, we first confirm, at the protein level, our previous cDNA array results, that SPARC increases expression of the …