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Articles 1 - 13 of 13

Full-Text Articles in Cancer Biology

Parp Inhibitor Upregulates Pd-L1 Expression And Enhances Cancer-Associated Immunosuppression, Shiping Jiao May 2017

Parp Inhibitor Upregulates Pd-L1 Expression And Enhances Cancer-Associated Immunosuppression, Shiping Jiao

UT GSBS Dissertations and Theses (Open Access)

With recent approvals for therapeutic antibodies that block CTLA4, PD-1 and PD-L1, immune checkpoints have emerged as new targets in cancer therapy. In addition, there is accumulating evidence highlighting the role of cancer-associated immunity in patient response to cytotoxic anticancer agents. Inhibitors of poly (ADP-ribose) polymerase (PARP) have shown substantial cytotoxic effects against tumors with defects in DNA damage responses. However, whether a crosstalk between PARP inhibition and immune checkpoints exists remains unclear. Here, it has been shown that PARP inhibitors (PARPis) upregulate PD-L1 expression in multiple cancer cell lines, human xenograft tumors, and syngeneic mouse tumors. Mechanistically, PARPi inactivates ...


Androgen Receptor And Prostate Cancer Cell Heterogeneity, Qu Deng May 2017

Androgen Receptor And Prostate Cancer Cell Heterogeneity, Qu Deng

UT GSBS Dissertations and Theses (Open Access)

Androgen receptor (AR) plays an important role in prostate cancer (PCa) development and has been the main therapeutic target in advanced PCa. AR expression is heterogeneous in both primary PCa and castration resistant prostate cancer (CRPC). However, the functional significance of AR heterogeneity in regulating PCa biology and response to androgen/AR-targeted therapies remains unclear. The overarching hypothesis for my Ph.D is that AR heterogeneity contributes to PCa development, progression, and therapy resistance. A more specific postulate is that PCa cells expressing AR (i.e, AR+) and PCa cells expressing little AR (i.e, AR-/lo) possess intrinsically distinct ...


Microenvironment-Induced Pten Loss By Exosomal Microrna Primes Brain Metastasis Outgrowth, Lin Zhang Dec 2016

Microenvironment-Induced Pten Loss By Exosomal Microrna Primes Brain Metastasis Outgrowth, Lin Zhang

UT GSBS Dissertations and Theses (Open Access)

Development of life-threatening cancer metastases at distant organs requires disseminated tumor cells’ adaptation to and co-evolution with the drastically different microenvironments of metastatic sites. Cancer cells of common origin manifest distinct gene expression patterns after metastasizing to different organs. Clearly, the dynamic interplay between metastatic tumor cells and extrinsic signals at individual metastatic organ sites critically impacts the subsequent metastatic outgrowth. Yet, it is unclear when and how disseminated tumor cells acquire the essential traits from the microenvironment of metastatic organs that prime their subsequent outgrowth. Here we show that primary tumor cells with normal expression of PTEN, an important ...


Regulation Of Breast Cancer Initiation And Progression By 14-3-3zeta, Chia-Chi Chang Aug 2016

Regulation Of Breast Cancer Initiation And Progression By 14-3-3zeta, Chia-Chi Chang

UT GSBS Dissertations and Theses (Open Access)

14-3-3ζ is a ubiquitously expressed family member of proteins that have been implicated to have oncogenic potential through its interactions and involvement in cancer initiation and progression. 14-3-3ζ belongs to the highly conserved 14-3-3ζ protein family and modulates numerous pathways in cancer. Overexpression of 14-3-3ζ is an early event, occurs in more than 40% of human breast cancer cases, and is associated with disease recurrence and poor prognosis. Metabolic reprogramming is a hallmark of cancer. Cancer cells elevate aerobic glycolysis to produce metabolic intermediates and reducing equivalents, thereby facilitating cellular adaptation to the adverse environment and sustaining fast proliferation. Interestingly ...


The Roles Of Malt1 In Nf-Κb Activation And Solid Tumor Progression, Deng Pan May 2016

The Roles Of Malt1 In Nf-Κb Activation And Solid Tumor Progression, Deng Pan

UT GSBS Dissertations and Theses (Open Access)

The transcription factor NF-κB plays a central role in many aspects of biological processes and diseases, such as inflammation and cancer. Although it has been suggested thatNF-κB is critical in tumorigenesis and tumor progression, the molecular mechanism by which NF-κB is activated in solid tumor remains largely unknown. In the current work, we focus on growth factor receptor-induced NF-κB activation and tumor progression, including epidermal growth factor receptor (EGFR)-induced NF-κB in lung cancer and heregulin receptor (HER2)-induced NF-κB in breast cancer. We found that Mucosa-associated lymphoma translocation protein 1 (MALT1), also known as paracaspase, is required for EGFR-induced ...


Identifying Protein Kinase Tbk1 As A Novel Inhibitor Of Intestinal Tumorigenesis, Amber L. Mathews Dec 2015

Identifying Protein Kinase Tbk1 As A Novel Inhibitor Of Intestinal Tumorigenesis, Amber L. Mathews

UT GSBS Dissertations and Theses (Open Access)

Colorectal cancer (CRC) is the third most common cancer diagnosed in women and men, causing almost 600,000 annual deaths worldwide. There is a clear need to understand how CRC forms and progresses in order to improve the strategies of CRC prevention and therapy. A major factor that drives the development of CRC is genetic mutations that lead to activation of oncogenes and inactivation of tumor suppressor genes in intestinal epithelial cells (IECs). In addition, the initiation and progression of CRC involve environmental and immunological factors. In particular, chronic inflammatory conditions are known as an important risk factor for CRC ...


Sustained Adrenergic Signaling Promotes Cervical Cancer Progression, Nouara C. Sadaoui Dec 2014

Sustained Adrenergic Signaling Promotes Cervical Cancer Progression, Nouara C. Sadaoui

UT GSBS Dissertations and Theses (Open Access)

Background: Chronic stress and sustained adrenergic signaling are known to promote tumor progression. The underlying mechanisms behind this process are not well understood. We examined the effects of sustained adrenergic signaling on cervical cancer progression through increased expression of HPV oncogenes, E6 and E7.

Materials and Methods: ADRβ expression levels were examined in patient-derived cervical cancer samples. We used an orthotopic model of cervical cancer to investigate the effects of restraint stress on tumor growth and metastasis. We evaluated the in vivo effects of a β-blocker, propranolol, and HPV E6/E7 siRNA. In vitro, ADRβ positive cervical cancer cells were ...


Diabetes And Obesity Induce Transcriptomic And Metabolomic Changes Enhancing Pancreatic Cancer Aggressiveness, Guermarie Velázquez Torres May 2014

Diabetes And Obesity Induce Transcriptomic And Metabolomic Changes Enhancing Pancreatic Cancer Aggressiveness, Guermarie Velázquez Torres

UT GSBS Dissertations and Theses (Open Access)

Pancreatic cancer is one of the most aggressive types of cancer, with poor prognosis that lacks effective diagnostic markers and therapies. It is expected that in 2014 the incidence and the mortality of pancreatic cancer in the United States will be 46,420 and 39,590 respectively. Diabetes and obesity are modifiable risk factors associated with accelerated pancreatic carcinogenesis and tumor progression, but the biological mechanisms are not completely understood. The purpose of this study is to demonstrate direct evidence for the mechanisms mediating these epidemiologic phenomena. Our hypothesis is that obesity and diabetes mellitus type 2 (DM2) accelerate pancreatic ...


T-Cell Treatments For Solid And Hematological Tumors, Drew C. Deniger Aug 2013

T-Cell Treatments For Solid And Hematological Tumors, Drew C. Deniger

UT GSBS Dissertations and Theses (Open Access)

Cell-based therapies have demonstrated potency and efficacy as cancer treatment modalities. T cells can be dichotomized by their T cell receptor (TCR) complexes where alpha/beta T cells (95% of T cells) and gamma/delta T cells (+T cells proliferated to clinically significant numbers and ROR1+ tumor cells were effectively targeted and killed by both ROR1-specific CAR+ T cell populations, although ROR1RCD137 were superior to ROR1RCD28 in clearance of leukemia xenografts in vivo. The second specific aim focused on generating bi-specific CD19-specific CAR+ gamma/delta T cells with polyclonal TCRgamma/delta repertoire on CD19+ artificial antigen presenting cells (aAPC). Enhanced ...


Mechanisms Underlying The Heterogeneous Sensitivities Of Cancer Cells To Proteasome Inhibitors, Matthew C. White May 2013

Mechanisms Underlying The Heterogeneous Sensitivities Of Cancer Cells To Proteasome Inhibitors, Matthew C. White

UT GSBS Dissertations and Theses (Open Access)

The mechanisms underlying cellular response to proteasome inhibitors have not been clearly elucidated in solid tumor models. Evidence suggests that the ability of a cell to manage the amount of proteotoxic stress following proteasome inhibition dictates survival. In this study using the FDA-approved proteasome inhibitor bortezomib (Velcade®) in solid tumor cells, we demonstrated that perhaps the most critical response to proteasome inhibition is repression of global protein synthesis by phosphorylation of the eukaryotic initiation factor 2-α subunit (eIF2α). In a panel of 10 distinct human pancreatic cancer cells, we showed marked heterogeneity in the ability of cancer cells to induce ...


Characterization Of Differentiation And Prognostic Biomarkers On Cd8+ Tumor-Infiltrating Lymphocytes In Metastatic Melanoma, Richard C. Wu May 2013

Characterization Of Differentiation And Prognostic Biomarkers On Cd8+ Tumor-Infiltrating Lymphocytes In Metastatic Melanoma, Richard C. Wu

UT GSBS Dissertations and Theses (Open Access)

CD8+ cytotoxic T lymphocytes (CTL) frequently infiltrate tumors, yet most melanoma patients fail to undergo tumor regression. We studied the differentiation of the CD8+ tumor-infiltrating lymphocytes (TIL) from 44 metastatic melanoma patients using known T-cell differentiation markers. We also compared CD8+ TIL against the T cells from matched melanoma patients’ peripheral blood. We discovered a novel subset of CD8+ TIL co-expressing early-differentiation markers, CD27, CD28, and a late/senescent CTL differentiation marker, CD57. This CD8+CD57+ TIL expressed a cytolytic enzyme, granzyme B (GB), yet did not express another cytolytic pore-forming molecule, perforin (Perf). In contrast, the CD8+CD57+ T ...


Increased Geranylgeranylated K-Ras Contributes To Antineoplastic Effects Of Farnesyltransferase Inhibitors., Mandy A. Hall May 2012

Increased Geranylgeranylated K-Ras Contributes To Antineoplastic Effects Of Farnesyltransferase Inhibitors., Mandy A. Hall

UT GSBS Dissertations and Theses (Open Access)

The Ras family of small GTPases (N-, H-, and K-Ras) is a group of important signaling mediators. Ras is frequently activated in some cancers, while others maintain low level activity to achieve optimal cell growth. In cells with endogenously low levels of active Ras, increasing Ras signaling through the ERK and p38 MAPK pathways can cause growth arrest or cell death. Ras requires prenylation – the addition of a 15-carbon (farnesyl) or 20-carbon (geranylgeranyl) group – to keep the protein anchored into membranes for effective signaling. N- and K-Ras can be alternatively geranylgeranylated (GG’d) if farnesylation is inhibited but are preferentially ...


Atm Signaling To Tsc2: Mechanisms And Implications For Cancer Therapy, Angela Alexander May 2011

Atm Signaling To Tsc2: Mechanisms And Implications For Cancer Therapy, Angela Alexander

UT GSBS Dissertations and Theses (Open Access)

Ataxia telangiectasia mutated (ATM) is a critical component of the cellular response to DNA damage, where it acts as a damage sensor, and signals to a large network of proteins which execute the important tasks involved in responding to the damage, namely inducing cell cycle checkpoints, inducing DNA repair, modulating transcriptional responses, and regulating cell death pathways if the damage cannot be repaired faithfully. We have now discovered that an additional novel component of this ATM-dependent damage response involves induction of autophagy in response to oxidative stress. In contrast to DNA damage-induced ATM activation however, oxidative stress induced ATM, occurs ...