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Discovery Of Novel Mechanisms Regulating Cancer Extravasation In The Chorioallantoic Membrane Model, Yohan Kim

Electronic Thesis and Dissertation Repository

Cancer metastasis is a multistep process that begins with the invasion of tumour cells into the stroma and migration towards the blood vessels. Tumour cells that have entered the bloodstream must then survive and leave by a process known as extravasation. Finally, extravasated cells proliferate and establish the secondary site in the metastatic cascade. Although extravasation encompasses key events during cancer cell invasion to aid in the development of effective treatments, an in vivo model that rapidly, reproducibly and economically recapitulates cancer cell extravasation is needed. Therefore, the objectives of my research were to 1) establish and validate an in …

The Role Of The Tau N-Terminal Phosphatase-Activating Domain And Phosphorylation At Thr175 In The Formation Of Tau Cytoplasmic Inclusions, Matthew A. Hintermayer

Electronic Thesis and Dissertation Repository

Cytoplasmic inclusions and fibrils of the microtubule-associated protein tau (tau protein) are a key neuropathological hallmark in tauopathies, including Alzheimer’s disease, chronic traumatic encephalopathy, and amyotrophic lateral sclerosis with cognitive impairment. Previous research has demonstrated that the phosphorylation of tau protein at Thr¹⁷⁵ is sufficient for the initiation of fibril formation both in vitro and in vivo. Here we use mutated tau protein constructs to demonstrate that phosphorylation at Thr¹⁷⁵ results in the aberrant exposure of an N-terminal phosphatase-activating domain (PAD). The tau PAD interacts with protein phosphatase 1 (PP1) leading to the activation of glycogen synthase …

Kallikrein-Related Peptidases Are Dysregulated In Pleomorphic Adenoma, Matthew D. Morrison

Electronic Thesis and Dissertation Repository

Objectives: Pleomorphic adenoma (PA) is the most common benign salivary gland tumor. Kallikrein-related peptidases (KLKs) have been identified as biomarkers in many human tumors and may influence tumor behavior. We investigated KLK1-15 messenger ribonucleic acid (mRNA) and proteins in PA specimens to determine a KLK expression profile for this tumor.

Methods: Fresh frozen PA tissue specimens (n = 26) and matched controls were subjected to RT-qPCR to detect KLK1-15 mRNA. Expression of KLK1, KLK12, KLK13 and KLK8 proteins were then evaluated via immunostaining techniques. Statistical analyses were performed with the level of significance set at P < .05.

Results: We observed downregulation …

Crispr Screen For Identification Of Kinases That Mediate Prostate Cancer Cell Invasion, Hamad Aldhafeeri

Electronic Thesis and Dissertation Repository

Metastasis is the primary cause of mortality in cancer patients. Inhibition of proteins that are involved in the regulation of metastasis are expected to suppress metastasis and represent treatment targets. Our focus is on prostate cancer metastasis and we have developed a novel high-throughput means of performing in vitro screens for regulators of prostate cancer metastasis. We propose to use a focused CRISPR library screen that will “knock out” all human kinases to determine which ones are responsible for prostate cancer metastasis. CRISPR is a potent genetic editing tool and was used to silence all kinases in prostate cells (BPH …

Protective Benefits Of Hydrogen Sulfide Treatment During Renal Transplantation, Ian Lobb

Electronic Thesis and Dissertation Repository

Ischemia/reperfusion injury (IRI) is inherent to renal transplantation (RTx) and is initiated when blood supply is necessarily removed during organ procurement (ischemia) and subsequently restored upon engraftment (reperfusion). During renal ischemia, ATP depletion causes tubular epithelial cell (TEC) injury and subsequent release of pro-inflammatory mediators. Upon reperfusion, influx of O₂ causes reactive oxygen species (ROS) production and infiltration of innate immune cells which release damaging ROS and proteases. Prolonged periods of IRI are associated with increased risk of delayed graft function (DGF) and decreased long-term graft survival. The endogenously produced gasotransmitter, hydrogen sulfide (H₂S), has recently been …

Immunohistochemical Studies Of Expression And Correlation Of Osteopontin, Cd44, And Integrin Αvβ3 In Selected Benign And Malignant Salivary Gland Tumours, Tommy Fok

Electronic Thesis and Dissertation Repository

Osteopontin (OPN) is a phosphorylated acidic glycoprotein that has been shown to play a vital role in tumourigenesis and metastases. The objective of this study was to determine the expression of OPN and its receptors (CD44 and integrin α_vβ₃) in several salivary gland cancers, and assess its clinical correlations.

Immunohistochemical techniques were used to semi-quantify the level of OPN expression and its receptors in normal salivary glands and different types of salivary gland tumour.

Our results show that in tumours of salivary gland origin, higher levels of OPN were detected in tumours which were malignant compared …

The Role Of Non-Canonical Wnt/Planar Cell Polarity Signalling In Breast Cancer Progression, Connor D. Macmillan

Electronic Thesis and Dissertation Repository

The role of planar cell polarity (PCP) signalling in breast cancer is unclear, as evidence shows that activation of this pathway with WNT5A can either promote or inhibit progression. Using the 21T cells, which represent distinct stages of breast cancer progression when grown in a mouse xenograft model (21PT, atypical ductal hyperplasia; 21NT ductal carcinoma in situ; 21MT-1, invasive mammary carcinoma), I hypothesized that WNT5A will promote progression only when VANGL1, another component of PCP signalling, is elevated.

Each 21T cell line showed distinct stage-specific morphologies when grown in a Matrigel “on-top” assay. WNT5A overexpression promoted progression to an invasive …