Neoplasms Commons^™

Anal Cancer Risk Factor Management Practices And The Barriers And Facilitators Of Addressing Anal Health In The Hiv Primary Care Setting, Crystal Martin Walker

Theses and Dissertations (ETD)

Background: The incidence of anal cancer is only 1-2 per 100,000 people in the general population, but in people living with HIV and AIDS (PLWHA), the incidence is far greater by about 80 times. This is a striking disproportion, and it is vital for the healthcare provider and healthcare system to become more attentive to the risk of anal cancer in high-risk populations such as PLWHA. There are a number of modifiable risk factors for anal cancer in PLWHA such as smoking, non-adherence to antiretroviral therapy (ART), and risky sexual behaviors. The HIV primary care provider (HIV PCP) plays a …

Molecular Characterization Of Glioblastoma Cancer Stem Cells, Jo Meagan Garner

Theses and Dissertations (ETD)

Malignant gliomas are locally aggressive, highly vascular tumors that have an overall survival time less than 14 months, and current therapies provide little improvement in the disease course and outcome. While glioblastoma multiforme (GBM) patients present uniform histological phenotypes, the molecular determinants of the disease vary considerably between individual cases resulting in complicated prognosis. The heterogeneity, aggressiveness and rapid tumor relapse of GBM is believed to be sustained by cancer stem-like cell populations that are able to initiate and maintain tumors. Although CSCs represent only a small fraction of cells within a tumor, their high tumor-initiating capacity and therapeutic resistance …

Development And Characterization Of A Recombinant Vesicular Stomatitis Virus (Rvsv) For The Treatment Of Glioblastoma, Erika A. Dillard

Theses and Dissertations (ETD)

Background: Over the past 30 years, little has changed in the treatment modalities and prognosis of patients suffering from Glioblastoma multiforme (GBM), the most common and by far the most devastating adult primary malignant brain tumor. Conventional therapies provide only a marginal increase in survival of GBM patients, post-diagnosis. Therefore, more novel means of treating GBM are needed to increase long-term survival and quality of life for those affected. Replication competent oncolytic viruses (OVs) have recently emerged as a possible option for treatment of high-grade gliomas. Particularly, recombinant vesicular stomatitis virus (rVSV), an enveloped, negative strand RNA virus, has shown …

Nkg2d Ligands In Cancer, Neha Das Gupta

Theses and Dissertations (ETD)

NK cell transplantation has been increasingly used to treat cancers that are resistant to chemotherapy. However, not all cancers are susceptible to NK cell killing. The prevalence and mechanisms of NK cell resistance have not been well elucidated. Because NKG2D is a major activating receptor on NK cells, we sought to test the hypothesis that NKG2D is the primary pathway in tumor cell recognition. Herein, we comprehensively assessed 20 cancer cell lines representing a broad array of cancer types. In line with our primary hypothesis, no cancer cell lines that expressed low levels of NKG2D ligands were susceptible to NK …

Tetraspanin Cd9: Contributions To Cancer Cell And Vascular Cell Phenotypes From The Sixth Man, Michael James Herr Ii

Theses and Dissertations (ETD)

Cancer and vascular disease are the two most predominant causes of mortality in the United States. Potential regulatory mechanisms for these two diseases have consumed research interests. Tetraspanins are cell surface proteins that organize the cell membrane. Cellular membrane organization is a prerequisite for cellular signaling to occur. Deregulation of cellular signaling often precedes the formation of cancer or vascular disease phenotypes. This insinuates the necessity to understand how tetraspanins contribute to membrane organization and subsequent downstream signaling. This work examines tetraspanin CD9 contributions in a model of cancer cell invasion and vascular cell contraction. The findings presented here demonstrate …

Identification Of Novel Hif1a Target Genes That Regulate Tumor Progression And Metastasis, Danielle L. Peacock

Theses and Dissertations (ETD)

Hypoxia is a hallmark of most solid tumors. In response to hypoxic stress tumor cells adapt by regulating survival, metabolism and angiogenesis. The heterodimeric HypoxiaInducible Factor (HIF) transcription factors are the master regulators of this response. HIFs play key roles in many critical aspects of cancer biology including angiogenesis, stem cell maintenance, metabolic reprogramming, invasion, metastasis and resistance to radiation therapy and chemotherapy. Overexpression of HIF-1α and HIF-2α has been documented in multiple human cancers and HIF-1 protein is over-expressed in ~30% of primary breast tumors and ~70% of metastases, which independently correlates with poor prognosis and decreased survival in …

The Protumorigenic Role Of Caspase-8 In Neuroblastoma, Devin Drew Twitchell

Theses and Dissertations (ETD)

Neuroblastoma (NB), the most common extracranial solid tumor in children, accounts for 15% of cancer-related deaths in pediatric patients. Caspase-8 (casp8), a proapoptotic protein, is silenced in approximately, 50-70% of neuroblastoma patient samples. Loss of casp8 has been suggested to increase NB metastasis and correlated, in some studies, with advanced-stage NB. Furthermore, decreased casp8 expression may facilitate neuroblastoma tumorigenesis by protecting cells from cell death mediated by either integrins or chemotherapeutics. Paradoxically, casp8 expression is maintained in 30-50% of NB patient samples giving rise to the possibility that casp8 may provide selective advantages for NB tumorigenesis. Caspase-8 is shown to …

Functional Study Of Hemogen Knockout Mouse Model, Peng Gao

Theses and Dissertations (ETD)

Mouse Hemogen (Hemgn) is regarded as a homologue of human Erythroid Differentiation Associated Gene (EDAG). EDAG overexpression has been postulated for association with some leukemia cases. Meanwhile, Hemgn has been found to contribute to Hoxb4 mediated hematopoietic stem cell expansion. Based on these postulations and evidences, a Hemgn knockout mouse model has been generated to study its function in normal and stress hematopoiesis. I confirmed the Hemgn expression in hematopoietic organs including bone marrow and spleen, as well as round spematids in testis. Hemgn is expressed in mouse hematopoietic stem cells and erythroid progenitor cells. Moreover, Hemgn was also found …

The Role Of The Yxxφ Motif In Cd82 Trafficking And Function, Mekel Marie Richardson

Theses and Dissertations (ETD)

CD82, a tetraspanin, is a tumor metastasis suppressor. Tetraspanins are membrane spanning proteins that play critical roles in diverse biological and pathological processes, e.g., the regulation of cancer metastasis. CD82 is ubiquitously expressed in various types of tissues, but its expression becomes down-regulated or lost in a majority of metastatic tumors. It inhibits tumor metastasis without affecting primary tumor growth. Cancer patients whose tumors contain CD82 exhibit minimal metastasis. We know that CD82 functions as a tumor metastasis suppressor but the mechanism by which this occurs is largely unknown. CD82 can be found on the plasma membrane as well as …

Inhibition Of Breast Cancer Angiogenesis And Metastasis Ay Targeting Hypoxia-Inducible Factor-1Α, Chikezie O. Madu

Theses and Dissertations (ETD)

The current clinical chemotherapy agents are not ideal for breast cancer as they are not curative, but only provide a modest extension of survival with sometimes a severely adverse effect on the patient’s quality of life. There is, therefore, an urgent need to search for new and more effective anti-breast cancer drugs. However, the existing screening system is inefficient and time-consuming despite the extremely large amount of small molecule compounds in database currently available, and thereby hindering the effort for selecting new and effective anti-cancer drugs.

The majority of locally advanced solid tumors contain regions of reduced oxygen availability. Hypoxia …

Discovery Of Dihydroartemisinin And Dasatinib Drug Combination To Cure Pooroutcome Bcr-Abl+ Acute Lymphoblastic Leukemia, Harpreet Singh

Theses and Dissertations (ETD)

Oncogenic signaling by the Philadelphia chromosome-encoded BCR-ABL fusion kinase initiates and drives both Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) and chronic myelogenous leukemia (CML). Food and Drug Administration (FDA)- approved BCR-ABL-specific kinase inhibitors (BCR-ABL–KIs) imatinib, dasatinib and nilotinib induce prolonged remissions in CML but poor leukemia-reduction and relapse-control in Ph+ ALL. The relative primary BCR-ABL–KI-resistance in Ph+ ALL patients carrying predominantly BCR-ABLWT disease cannot be attributed to drug-resistant BCR-ABL mutations (BCR-ABLMUTANTS), and remains poorly understood.

We established a cell-based platform to evaluate the modulation of anti-Ph+ ALL activity of drugs by both tumor-extrinsic cytokines normally present in the leukemia …

Insights Into P53-Dependent Apoptotic Signaling And Cell Fate Vis-A-Vis Functional Cooperation Among Bcl-Xl, Cytoplasmic P53, And Puma, John C. Fisher

Theses and Dissertations (ETD)

Following DNA damage, nuclear p53 induces the expression of PUMA (p53 upregulated modulator of apoptosis), a BH3‑only protein that binds and inhibits the anti‑apoptotic BCL‑2 repertoire, including BCL‑xL. Structural investigations of PUMA and the BCL‑xL×PUMA BH3 domain complex by X‑ray crystallography and nuclear magnetic resonance (NMR) spectroscopy reveal a novel, PUMA‑induced, domain‑swapped dimerization of BCL‑xL that requires a π‑stacking interaction between PUMA W71 and BCL‑xL H113. PUMA is an intrinsically disordered protein, but upon interaction with BCL‑xL, PUMA W71 and the PUMA BH3 domain residues fold into an alpha helix and subtly remodel BCL‑xL to trigger its dimerization. Wild type …

Cd151 Reinforces Vascular Stability By Balancing Endothelial Cell Adhesion And Cytoskeletal Tension, Feng Zhang

Theses and Dissertations (ETD)

Tetraspanin CD151 is highly expressed in endothelial cells and regulates pathological angiogenesis. However, the mechanism by which CD151 promotes vascular morphogenesis and whether CD151 engages other vascular functions are unclear. We observed that CD151 is required for the maintenance of endothelial capillary-like structures formed in vitro and the integrity of lung endothelial cell-cell contacts in vivo. As a master regulator of endothelial cell-matrix and cell-cell adhesions, CD151 is needed for the optimal functions of various cell adhesion proteins such as integrin, cadherin, and CD44. The loss of CD151 elevates the cellular intrinsic contraction by upregulating RhoA signaling and downregulating of …

Tamoxifen: Mechanisms Of Resistance, Cyrus Mccoy Adams

Theses and Dissertations (ETD)

The role of estrogen in breast cancer has been recognized for decades. The selective estrogen receptor modulator tamoxifen was the first targeted therapy for the treatment of breast cancer. It was also the first drug approved by the FDA for the reduction of breast cancer risk. While tamoxifen has extended the lives of countless patients with breast cancer, resistance to tamoxifen remains a significant clinical problem. Work over the last two decades has greatly enhanced our understanding of the molecular mechanisms by which breast cancer cells may become resistant to tamoxifen treatment. Here I review our current understanding of the …

Evaluating The Impact Of The Guatemalan Nursing Program On Staff, Organizational, And Clinical Outcomes, Sara Williamson Day

Theses and Dissertations (ETD)

There is great disparity between the outcome of childhood cancer in developed and developing countries. Nurses, who comprise the largest group of health care professionals globally, are essential to successful treatment. Pediatric oncology education is generally unavailable for nurses in developing countries. This lack of education is likely to contribute to the disparity in survival rates, as undereducated nurses are unable to meet the demands of pediatric cancer care. A second critical problem in developing countries is the workload of the nurse, with a patient nurse ratio reported as high as 30 patients per one nurse.

In 2006, the quality …

The Use Of Preclinical Models To Improve The Treatment Of Retinoblastoma, Katie Marie Nemeth

Theses and Dissertations (ETD)

Rodent models play an essential role in the development of new chemotherapeutics and dosing regimes. It is often difficult to carryout a clinical study for pediatric cancers due to the small patient population. Retinoblastoma, a pediatric cancer of the eye, is one example of a pediatric cancer that can benefit from preclinical studies. Over the years various retinoblastoma rodent models have been developed used to test various combination of broad-spectrum systemic chemotherapy. It was found form these studies that the combination of topotecan and carboplatin was effective. However both drugs cause myelosuppression and therefore administrating both of these drugs systemically …

Pain Management In Nursing Home Residents With Cancer And Dementia With And Without Hospice Services, Todd Bryant Monroe

Theses and Dissertations (ETD)

Aims: We sought to identify differences in pain management between two groups; nursing home residents with malignant cancer and dementia with and without hospice services.

Methods: Decedent records from 2003-2009 were assessed for diagnosis of dementia and cause of death as cancer. Ten malignant cancer diagnoses were determined a priori from the CDC 2004 data on the top 10 malignant cancers for all races and genders. Fifty-five decedents from 10 nursing homes were included in the final sample. Four instruments were used: Minimum Data Set (MDS) a standardized assessment tool required of most U.S. nursing homes. A large …

Pax5 Haploinsufficiency Cooperates With Bcr-Abl1 To Induce Acute Lymphoblastic Leukemia, Christopher B. Miller

Theses and Dissertations (ETD)

Acute lymphoblastic leukemia (ALL) is the commonest pediatric malignancy and comprises several distinct subtypes each with its own unique pathogenesis, clinical behavior, and response to therapy. Chromosomal aberrations are a hallmark of ALL but alone fail to induce leukemia. Pediatric ALLs can be divided into several categories based on the expression of several genetically conserved chromosomal translocations including the t(9,22)[BCR-ABL1], t(1,19)[TCF3-PBX1], t(12,21)[ETV6-RUNX1], MLLrearranged leukemia’s, hyperdiploid and hypodiploid karyotypes, and T-lineage leukemia. Each translocation confers a characteristic transforming phenotype within the cell in which it originates but is alone insufficient to induce overt leukemia. …

The Role Of Inflammation In The Early Radiation Response, Christy Marie Wilson

Theses and Dissertations (ETD)

Radiation is one of the principal treatments for adults and children with brain tumors, and is one of the oldest established treatments for tumors of all types. Currently, the limiting factor for the use of radiation is the effect on normal tissue adjacent to the tumor. Toxicity, including early and late effects from radiation, limits the dose administered to the tumor and reduces the probability of cure. This work has three aims in its attempt to understand and limit early radiation damage: characterize the role of the inflammatory molecules tumor necrosis factor alpha (TNF) and intracellular adhesion molecule-1 (ICAM-1) in …

The Combined Effect Of In-Situ Tumor And Irradiation On Peritumoral Brain Vasculature, Janice Ann Zawaski

Theses and Dissertations (ETD)

In the USA, 200,000 brain tumors are diagnosed each year with glioma representing 8.4% of the 200,000. The standard treatment for glioma consists of surgical resection, when possible, followed by radiation therapy (RT) and/or chemotherapy. Radiation therapy is one of the most effective treatments of brain tumors; however, the therapeutic ratio of RT is limited by damage to the normal tissue. We hypothesize that tumor growth has an adverse effect on the peritumoral tissue through the angiogenic/inflammatory environment it creates rendering it susceptible to further damage by RT which may be prevented by using anti-angiogenic/anti-inflammatory agents. We have developed a …

Manipulation Of The Moloney Murine Leukemia Virus Envelope Protein In An Effort To Develop Directly And Indirectly Targeted Retroviral Vectors For Use In Human Gene Therapy, Geneva M. Vasser

Theses and Dissertations (ETD)

Highly effective, targeted therapies against cancer would revolutionize the way people recover from this devastating illness. Gone would be the lingering side effects of the current non-specific treatments and in their place would be faster recovery times, better quality of life both during and after treatment, and less ambiguity about whether or not treatment was effective. This concept will elude modern medicine until treatments can be tailored to the patient's individual and unique disease. This concept of a transient, targeted, and tailored vehicle aimed at cancer cells lends itself to the use of replication deficient retroviral gene therapy vectors with …

Molecular Profile Of Women With And Without Secondary Breast Cancer After The Treatment Of Pediatric Hodgkin Lymphoma, Belinda Neal Mandrell

Theses and Dissertations (ETD)

dentification of genetic risk factors associated with the development of secondary cancers would facilitate identification of at risk patients and permit modification of therapy and heightened surveillance that may reduce cancer-related morbidity and mortality. Women survivors of pediatric Hodgkin lymphoma (HL) have an increased risk of morbidity and mortality associated with secondary effects of therapy, with a 35-75 fold excess risk of developing breast cancer over the general population. The mechanism for secondary breast cancer among Hodgkin survivors is not understood. Researchers have postulated that the familial characteristics of HL could be associated with mutations found within familial cancer syndromes; …

Sleep, Fatigue And Caregiver Burden In Parents Of Children With Acute Lymphoblastic Leukemia (All), Jerithea Tidwell

Theses and Dissertations (ETD)

Parents often report that their child diagnosed with acute lymphoblastic leukemia (ALL) and receiving steroid therapy experience altered sleep patterns, fatigue, irritability, and other behavioral changes. As a consequence, parents may experience altered sleep, fatigue, and increased caregiver burden. If so, the differences seen in parental sleep efficiency and sleep duration may be attributed to the child experiencing altered sleep secondary to receiving dexamethasone. The purpose of this study was to describe, caregiver sleep, fatigue, and caregiver burden immediately before and during their child’s dexamethasone pulse in continuation therapy for ALL and to compare parent quality of sleep and fatigue …

Uncovering P53 Mutations And Abnormal Gene Expression In Pediatric Adrenocortical Cancer, Alina Nico West

Theses and Dissertations (ETD)

Pediatric adrenocortical cancer is extremely rare and often fatal (approximately 0.3-0.4 cases per million worldwide; 50% 5-year survival). The incidence of pediatric adrenocortical cancer in southern Brazil is 10-15 times higher than the worldwide incidence. Due to the rarity of adrenocortical cancer, especially in children, underlying gene dysregulation and mechanisms of tumorigenesis of the adrenal gland are very poorly described in the literature. However, it is well-known that the tumor suppressor p53, which is mutated in over 50% of all human cancers, is commonly mutated in pediatric adrenocortical cancer. In addition, evidence strongly suggests that if a child has adrenocortical …

The Role Of Multi-Drug Resistance Associated Protein 4 And P-Glycoprotein In Resistance Of Neuroblastoma To Topotecan And Irinotecan, Patricia Kellie Turner

Theses and Dissertations (ETD)

High-risk neuroblastoma presents a significant therapeutic challenge because the 5-year survival rate remains less than 30% despite the use of surgery, multi-agent chemotherapy, radiation, and autologous bone marrow transplant. Novel therapeutic modalities are under development. The camptothecin analogs topotecan and irinotecan have been identified as successful cytotoxic agents. For topotecan, pharmacokinetically guided dosing to achieve a systemic exposure associated with preclinical anti-tumor activity in neuroblastoma xenograft models is feasible and has elicited favorable responses in children with high-risk neuroblastoma. However, some children with high-risk disease did not respond to the putatively effective topotecan systemic exposure. These children represent a subset …

Dental Maturation In Children Treated For Acute Lymphocytic Leukemia, Michael Grey Weathersby

Theses and Dissertations (ETD)

Acute lymphocytic leukemia (ALL) is a life-threatening disease primarily affecting children. Treatment currently consists of chemotherapy sometimes in combination with head irradiation. The literature documents the damage of treatment to the teeth (e.g., congenital absence, microdontia, abnormal crown- root ratios). The present study assessed the effects of treatment for ALL on the tempos of dental maturation (i.e., dental age) in a mixed longitudinal sample of 72 children treated for ALL at St Jude's Children's' Research Hospital, Memphis, Tennessee. Panoramic radiographs had been taken as indicated to assess and maintain dental health in this retrospective study. Dental age was quantified both …

Hand-Wrist Bone Age In Children Treated For Acute Lymphoblastic Leukemia, Mary Elizabeth Martin

Theses and Dissertations (ETD)

Acute Lymphoblastic Leukemia (ALL) is the most common malignancy of childhood, constituting 31 percent of all childhood malignancies. Treatment strategies to target ALL include chemotherapeutic agents, irradiation of the neck and/or spine, and bone marrow transplantation. The aggressive nature of antineoplastic therapies often produces numerous craniofacial and dental sequelae as well as additional harmful effects to the entire body. Cranial irradiation may adversely affect the hypothalamic-pituitary axis decreasing growth hormone production. Consequently, children with ALL may experience a transient or permanent reduction in growth iatrogenically. Hand-wrist radiographs are valuable for evaluating maturational status in children with ALL. These radiographs allow …