Medicine and Health Sciences Commons^™

Characterizing The Effects Of Antiandrogens And Senolytics To Enhance The Therapeutic Response To Castration-Resistant Prostate Cancer, Justin M. Silverman

Theses and Dissertations

Prostate cancer is the most frequently diagnosed cancer in males and the second most common cause of cancer deaths. Androgen deprivation therapy, whether through surgical or chemical castration, is the mainstay for treatment of advanced prostate cancer; however, despite an initial response, most patients eventually develop a progressive PSA rise, and castration- sensitive prostate cancer gives rise to castration-resistant prostate cancer. The standard of care therapy includes the antiandrogens such as enzalutamide and abiraterone acetate as well as the microtubule poison, docetaxel, and various immunotherapies; however, while prostate cancer research is progressing, there continues to be a compelling need for …

The Effects Of Autophagy And Senescence On Sensitivity To Cisplatin In Head And Neck Cancer, Zara H. Siddiqui

Theses and Dissertations

While current treatments in cancer, such as chemotherapy and radiation, can generally be effective in eliminating disease in patients, there also exists the possibility of recurrence of cancer cells over time. In patients diagnosed with locally advanced head and neck carcinoma, about 50-60% develop a loco-regional recurrence within two years, and 20-30% of patients develop metastatic disease at distant sites in the body [5]. On a cellular level, one mechanism for this survival may be that natural mechanisms such as autophagy and senescence play a role in allowing cells to survive after undergoing treatment. One standard of care chemotherapy for …

Modulation Of Autophagy And Senescence To Enhance The Response To Therapy In Triple Negative Breast Cancer, Liliya Tyutyunyk-Massey

Theses and Dissertations

Abstract

Although great strides have been made over the decades in development and optimization of anti-cancer therapies, even highly effective drugs often fail to completely eliminate tumors. Residual tumor cells can enter into a state of dormancy for prolonged periods of time but eventually are able to regain proliferative capacity and reemerge as chemotherapy-resistant disease. Because recurrent disease is a leading contributor to patient’s mortality, it is paramount to identify strategies for effectively destroying residual tumor cells.

Cytotoxic drugs and ionizing radiation are used as standard therapies in a variety of cancers. These modalities induce apoptosis, autophagy and senescence. Senescence …

Novel Insights Into The Contribution Of Cellular Senescence To Cancer Therapy: Reversibility, Dormancy And Senolysis., Tareq Saleh

Theses and Dissertations

Cellular senescence a specialized form of growth arrest that contributes to the pathogenesis of several aging-related disorders including cancer. While by definition tumor cells are considered immortalized, they can undergo senescence when exposed to conventional and targeted cancer therapy. Therapy-Induced Senescence (TIS) represents a fundamental response to therapy and impacts its outcomes. However, TIS has been considered a positive therapeutic goal since senescent tumor cells are expected to enter a state of permanent growth abrogation. In this work we examined the hypothesis that a subpopulation of senescent cells can re-acquire proliferative potential after a state of senescent dormancy, indicating that …

Cytoprotective Versus Non-Protective Autophagy Induced By Radiation In Head And Neck Cancer Cells, Duaa Bakhshwin

Theses and Dissertations

The primary treatment options for head and neck cancer are radiation therapy or surgery, or both combined; chemotherapy is often used as an additional, or adjuvant, treatment. Patients treated with radiotherapy are exposed to a high cumulative dose of radiation over a period of time and there is a 17-33% chance of recurrence. High cumulative doses of radiation, a long time course of treatment, side effects and the possibility of recurrence provide the rationale for developing approaches for radiation sensitization, which could be helpful to patients in decreasing the dose, duration of radiation, side effects, or the chance of recurrence. …

Radiation Sensitization Of Breast Cancer Cells By Vitamin D Through The Promotion Of Autophagic Cell Death, Eden Wilson

Theses and Dissertations

Radiation therapy is a widely used tool in cancer therapy and is frequently offered as the first line of treatment for cancers of the breast. While radiotherapy is often initially effective in killing tumor cells or suppressing their growth, there are factors that confer tumor cell resistance to irradiation. Development of resistance may lead to disease recurrence despite the use of surgery, chemotherapy and radiation therapy. A primary goal of the studies in Dr. Gewirtz’s laboratory is to develop strategies to overcome resistance to radiation (and chemotherapy) in breast cancer, with the ultimate goal of preventing or attenuating disease recurrence. …

Role Of Autophagy In Radiosensitization Of Breast Tumor Cells, Molly L. Bristol

Theses and Dissertations

In MCF-7 breast tumor cells, ionizing radiation promoted autophagy that was cytoprotective; pharmacological or genetic interference with autophagy induced by radiation resulted in growth suppression and/or cell killing (primarily by apoptosis). The hormonally active form of vitamin D, 1,25D3, also promoted autophagy in irradiated MCF-7 cells, sensitized the cells to radiation and suppressed the proliferative recovery that occurs after radiation alone. 1,25D3 also enhanced radiosensitivity and promoted autophagy in MCF7 cells that overexpress Her-2/neu as well as in p53 mutant Hs578t breast tumor cells. In contrast, 1,25D3 failed to alter radiosensitivity or promote autophagy in the BT474 breast tumor cell …

Cis 3,4', 5-Trimethoxy-3'-Aminostilbene (Stilbene 5c) Induces Apoptosis And Protective Autophagy In B16f10 Melanoma Cells, Betelehem Asnake

Theses and Dissertations

The weak selectivity of chemotherapeutic drugs against tumors has sustained efforts to develop better chemotherapeutic agents that are more potent and selective at destroying tumor cell populations versus normal tissues. This project focuses on evaluating the cell killing effects of the microtubule inhibitor, stilbene 5c, against melanoma cancer. We utilized an in vitro murine melanoma model to study the effects of stilbene 5c on tumor proliferation and survival, as well as growth arrest and cell death. Our findings indicate that stilbene 5c promotes dose dependent cell death in melanomas with the induction of apoptosis and autophagy. The role of autophagy …

Cell Death And Sustained Senescence Arrest In Colon Carcinoma And Melanoma Tumor Cells In Response To The Novel Microtubule Poison, Jg-03-14, Jonathan Biggers

Theses and Dissertations

Previous studies from this and other laboratories have shown that the novel microtubule poison, JG-03-14, which binds to the colchicine binding site of tubulin, has the capacity to promote both autophagy and apoptosis in breast tumor cells, as well as interfering with endothelial cell function and potentially disrupting tumor vasculature. The current work was designed to investigate the interaction between JG-03-14 and cell culture models of colon carcinoma and melanoma, specifically HCT116 human colon carcinoma cells and B16F10 murine melanoma cells. In both cases, JG-03-14 promoted death in the bulk of the treated population. FACS analysis, DAPI and TUNEL staining …

The Substituted Pyrrole Jb-03-14 Induces Autophagic Cell Death And Growth Arrest In Breast Tumor Cells, Christopher Ryan Arthur

Theses and Dissertations

The use of chemotherapy in the treatment of cancer has stimulated the demand for better chemotherapeutic agents that are more potent at destroying tumor cell populations and more selective for the specific tumor versus normal host tissues. This project is directed at discovering new anti-tumor agents that are effective against breast cancer based on structures derived from marine organisms, specifically brominated pyrroles. We utilized an in vitro breast cancer model to study the effects of pyrroles on tumor proliferation and survival, as well as growth arrest and cell death. Our findings indicate that the substituted pyrrole JG-03-14 induces time dependent …