Cell and Developmental Biology Commons^™

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 …

A Novel Function For 12-Lipoxygenase In C-Met And Integrin Β4 Axis Crosstalk, Elizabeth Tovar

Wayne State University Dissertations

Cancer cell metastasis is the single most threatening occurrence of tumor progression and predicts patient prognosis as well as survival. Invasion can be regulated by the Met receptor tyrosine kinase (c-Met), integrin beta4, and the lipid enzyme, 12-Lipoxygenase (12-LOX). Therefore we sought to determine if beta4, c-MET and 12-LOX comprise a signaling axis. c-Met is implicated in cancer cell dissemination through regulation of invasion in EMT where cell-cell junctions are disturbed to allow motility. Furthermore, beta4 promotes cellular adhesion to the extracellular matrix through hemidesmosomes. However, the homeostatic signaling functions of beta4's cytoplasmic tail can be hijacked by growth factor …

Effect Of Long Term Rapamycin Treatment On Mtor Signalling Network In Colon And Liver Of C57bl/6 Mice, John Sorge

Wayne State University Theses

Many studies have investigated the effects of rapamycin on aging and cancer. However, the effects of long-term rapamycin supplementation on a cancer model have not been performed. This is the first study that investigates the effects of long-term supplementation of rapamycin in a cancer model. ACF analysis of colon tissues in mice showed no significant difference between controls and those supplemented with rapamycin. Factors such as energy balance, cellular environment, PI3K/Akt/mTOR pathway, and more have been assessed in this study. The duration of rapamycin supplementation seems to play an important role in the protection against cancer. Ultimately, this study suggests …

Targeting Cxcr4 With Ctce-9908 Inhibits Prostate Tumor Metastasis, Donald Wong, Pridvi Kandagatla, Walter Korz, Sreenivasa R. Chinni

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

CXCL12/CXCR4 transactivation of epidermal growth factor family receptors in lipid raft membrane microdomains on cell surface is thought to mediate tumor growth and subsequent development of metastatic disease. CTCE-9908 is a known inhibitor of CXCR4. Herein, we tested the efficacy of CTCE-9908 in inhibiting prostate cancer cell growth, invasion, and metastasis.

Methods

We used a panel ofin vitroassays utilizing human prostate cancer cell lines and anin vivoorthotopic prostate cancer model to assess the anti-tumoral activity of CTCE-9908.

Results

We demonstrated that (a) CTCE-9908 treatment resulted in no significant change in the growth of PC-3 and C4-2B cells; (b) …

Recombinant Interleukin-21 Plus Sorafenib For Metastatic Renal Cell Carcinoma: A Phase 1/2 Study, Shailender Bhatia, Brendan, Marc S. Ernstoff, Michael, Elisabeth I. Heath, Wilson H. Miller Jr, Igor Puzanov, David I. Quinn, Thomas, Peter Vanveldhuizen, Kelly, Jeremy, Rachel, Naomi, Sonia, John A. Thompson

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Despite the positive impact of targeted therapies on metastatic renal cell carcinoma (mRCC), durable responses are infrequent and an unmet need exists for novel therapies with distinct mechanisms of action. We investigated the combination of recombinant Interleukin 21 (IL-21), a cytokine with unique immunostimulatory properties, plus sorafenib, a VEGFR tyrosine kinase inhibitor.

Methods

In this phase 1/2 study, 52 mRCC patients received outpatient treatment with oral sorafenib 400 mg twice daily plus intravenous IL-21 (10–50 mcg/kg) on days 1–5 and 15–19 of each 7-week treatment course. The safety, antitumor activity, pharmacokinetic and pharmacodynamic effects of the combination were …

Regulation Of Nkcc2 Trafficking By Vesicle Fusion Proteins Vamp2 And Vamp3 In The Thick Ascending Limb, Paulo Sebastian Caceres Puzzella

Wayne State University Dissertations

The thick ascending limb (TAL) in the kidney regulates extracellular fluid volume and blood pressure. The Na/K/2Cl cotransporter NKCC2 plays a central role in NaCl absorption by the TAL and blood pressure. NKCC2 trafficking to the apical membrane is a major mechanism to control NKCC2 activity. However, little is known about the proteins that mediate NKCC2 trafficking. Inhibition of the vesicle fusion proteins VAMP2 and VAMP3 blunts the increase in surface NKCC2 expression and NaCl absorption in response to stimulation by cAMP. In other cells, VAMPs mediate fusion of exocytic vesicles with the plasma membrane. Whether VAMP2 and VAMP3 mediate …

Effects Of Altering The Peroxisomal Redox State In Models Of Degenerative Disease, Courtney Rose Giordano

Wayne State University Dissertations

Peroxisomes are important regulators of cellular redox balance and function as a signaling platform to regulate anti-aging metabolic and communication networks. In addition the organelle has emerged as a major player in maintaining cellular ROS at an optimal level. At such levels, these ROS are involved in initiation of signaling cascades and that produce an array of anti-aging and disease processes. However, as cells age over time, ROS amass within the peroxisome and elsewhere in the cell. This leads to an imbalance in oxidative homeostasis and results in compromised signaling networks. The goal of this dissertation was to treat disease …

Mitochondrial Dynamics: Exploring A Novel Target Against Myocardial Ischemia-Reperfusion Injury, Yi Dong

Wayne State University Dissertations

Mitochondrial fusion and fission, collectively termed mitochondrial dynamics, are among the core mechanisms responsible for maintaining mitochondrial health and functional integrity. Dynamin-related protein 1 (DRP1) is a key regulator of mitochondrial fission. Recent studies suggest that i) mitochondrial dynamics, particularly, mitochondrial fission, serves as a mediator of cell fate in the setting of ischemia-reperfusion (IR) injury, and, ii) inhibition of DRP1 and mitochondrial fission provides cardioprotection against IR injury. However, the precise role of DRP1 translocation to mitochondria in the pathogenesis of myocardial ischemia-reperfusion injury has not been established.

Using an established model of hypoxia-reoxygenation (HR) in cultured HL-1 cardiomyocytes, …

Cxcr2 Macromolecular Complex In Pancreatic Cancer: A Potential Therapeutic Target In Tumor Growth, Shuo Wang

Wayne State University Dissertations

The signaling mediated by the chemokine receptor CXC chemokine receptor 2 (CXCR2) plays an important role in promoting the progression of many cancers, including pancreatic cancer, one of the most lethal human malignancies. CXCR2 possesses a consensus PSD-95/DlgA/ZO-1 (PDZ) motif at its carboxyl termini, which might interact with potential PDZ scaffold/adaptor proteins. We have previously reported that CXCR2 PDZ motif-mediated protein interaction is an important regulator for neutrophil functions. Here, using a series of biochemical assays, we demonstrate that CXCR2 is physically coupled to its downstream effector phospholipase C-β3 (PLC-β3) that is mediated by PDZ scaffold protein Na(+)/H(+) exchange regulatory …

Characterization Of Adult Zebrafish Retinal Regeneration Following Two Different Damage Models, Jennifer Lee Thomas

Wayne State University Dissertations

Unlike mammals, zebrafish can regenerate all of their retinal neurons through Müller glial cells, which respond to retinal damage by re-entering the cell cycle to create clusters of progenitor cells. The progenitors continue to proliferate as they migrate to the site of damage, where they ultimately differentiate into new retinal neurons. In contrast, Müller glia of the mammalian retina respond to injury with reactive gliosis, which if persistent, can lead to loss of Müller cell function and devastating vision loss. Despite this, multiple lines of evidence suggest that mammalian Müller glial cells possess a latent ability to regenerate retinal neurons. …

Regulation Of Inositol Biosynthesis And Cellular Consequences Of Inositol Depletion: Implications For The Mechanism Of Action Of Valproate, Rania M. Deranieh

Wayne State University Dissertations

Inositol is a six-carbon cyclitol that is ubiquitous in biological systems. It is a precursor for the synthesis of numerous biologically important compounds, including inositol phosphates and phosphoinositides that are essential for cell function and viability. Inositol compounds play a role in membrane formation, gene regulation, signaling, regulation of ion channels, and membrane trafficking. Furthermore, inositol regulates hundreds of genes, including those involved in the biosynthesis of inositol and phospholipids. While transcriptional regulation of inositol biosynthesis has been extensively studied and well characterized, regulation of inositol biosynthesis at the enzymatic level has not been addressed. The current study shows that …

Junctional Sarcoplasmic Reticulum Protein Processing And Trafficking In Cardiac Tissue And Primary Cultured Cardiomyocytes, Naama Sleiman

Wayne State University Dissertations

Junctional SR is an important and unique ER subdomain in the adult myocyte that releases Ca2+ through the actions of an exclusive set of resident proteins. Cardiac calsequestrin (CSQ2) undergoes two co-translational modifications: N-linked glycosylation on 316Asn, and phosphorylation by protein kinase CK2 on a cluster of 3 serines in its tail. In the heart, CSQ2 molecules undergo extensive mannose trimming by ER mannosidase(s), a posttranslational process that often regulates protein breakdown. To investigate CSQ2 protein processing in cardiomyopathy models, studies were performed to test whether CSQ2 glycan structures would be altered in heart tissue from mongrel dogs induced into …