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Cancer is the second leading cause of death in the United States and novel methods of treating advanced malignancies are of high importance. Of these deaths, prostate cancer and breast cancer are the second most fatal carcinomas in men and women respectively, while pancreatic cancer is the fourth most fatal

Cancer is the second leading cause of death in the United States and novel methods of treating advanced malignancies are of high importance. Of these deaths, prostate cancer and breast cancer are the second most fatal carcinomas in men and women respectively, while pancreatic cancer is the fourth most fatal in both men and women. Developing new drugs for the treatment of cancer is both a slow and expensive process. It is estimated that it takes an average of 15 years and an expense of $800 million to bring a single new drug to the market. However, it is also estimated that nearly 40% of that cost could be avoided by finding alternative uses for drugs that have already been approved by the Food and Drug Administration (FDA). The research presented in this document describes the testing, identification, and mechanistic evaluation of novel methods for treating many human carcinomas using drugs previously approved by the FDA. A tissue culture plate-based screening of FDA approved drugs will identify compounds that can be used in combination with the protein TRAIL to induce apoptosis selectively in cancer cells. Identified leads will next be optimized using high-throughput microfluidic devices to determine the most effective treatment conditions. Finally, a rigorous mechanistic analysis will be conducted to understand how the FDA-approved drug mitoxantrone, sensitizes cancer cells to TRAIL-mediated apoptosis.
ContributorsTaylor, David (Author) / Rege, Kaushal (Thesis advisor) / Jayaraman, Arul (Committee member) / Nielsen, David (Committee member) / Kodibagkar, Vikram (Committee member) / Dai, Lenore (Committee member) / Arizona State University (Publisher)
Created2013
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This research addresses the need for improvement in radiation sensors for applications of ionizing radiation such as radiotherapy. The current sensors involved are polymer gel dosimeters, MOSFETs, radio-chromic films, etc. Most of the sensors involved require expensive equipment's and processing facilities for readout. There is still a need to develo

This research addresses the need for improvement in radiation sensors for applications of ionizing radiation such as radiotherapy. The current sensors involved are polymer gel dosimeters, MOSFETs, radio-chromic films, etc. Most of the sensors involved require expensive equipment's and processing facilities for readout. There is still a need to develop better sensors that can be clinically applied. There are numerous groups around the world trying to conceive a better dosimeter. One of the radiation sensors that was developed recently was based on fluorescence signal emitted from the sensor. To advance the field of radiation sensors, a visual indicator has been developed in-lab as a method of detect ionizing radiation. The intensity of change in color is directly dependent on the amount of incident ionizing radiation. An aqueous gold nanoparticle sensor can be used to accurately determine the incident amount of ionizing radiation1. A gold nanoparticle sensor has been developed in lab with the use of hexadecyltrimethylammonium bromide (C16TAB) as the templating molecule. In the presence of ionizing radiation, the colorless gold salt is reduced and templated, creating a dispersion within the fluid1. The formation of suspended nanoparticles leads to a color change that can be visually detected and accurately analyzed through the employment of a spectrometer. Unfortunately, the toxicity of C16TAB is high. It is expected the toxicity can be reduced by replacing C16TAB with an amino acid, as amino acids can act as templating molecules in the solution and many are naturally occuring2. The experiments included a screening of 20 natural amino acids and 12 unnatural amino acids with the gold salt solution in the presence of ionizing radiation. Stability and absorbance testing was conducted on the amino acid sensors. Additional screening of lead amino acid sensors at various concentrations of irradiation was conducted.
ContributorsGupta, Saumya (Co-author) / Rege, Kaushal (Co-author, Thesis director) / Pushpavanam, Karthik (Co-author, Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
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Relapse after tumor dormancy is one of the leading causes of cancer recurrence that ultimately leads to patient mortality. Upon relapse, cancer manifests as metastases that are linked to almost 90% cancer related deaths. Capture of the dormant and relapsed tumor phenotypes in high-throughput will allow for rapid targeted drug

Relapse after tumor dormancy is one of the leading causes of cancer recurrence that ultimately leads to patient mortality. Upon relapse, cancer manifests as metastases that are linked to almost 90% cancer related deaths. Capture of the dormant and relapsed tumor phenotypes in high-throughput will allow for rapid targeted drug discovery, development and validation. Ablation of dormant cancer will not only completely remove the cancer disease, but also will prevent any future recurrence. A novel hydrogel, Amikagel, was developed by crosslinking of aminoglycoside amikacin with a polyethylene glycol crosslinker. Aminoglycosides contain abundant amount of easily conjugable groups such as amino and hydroxyl moieties that were crosslinked to generate the hydrogel. Cancer cells formed 3D spheroidal structures that underwent near complete dormancy on Amikagel high-throughput drug discovery platform. Due to their dormant status, conventional anticancer drugs such as mitoxantrone and docetaxel that target the actively dividing tumor phenotype were found to be ineffective. Hypothesis driven rational drug discovery approaches were used to identify novel pathways that could sensitize dormant cancer cells to death. Strategies were used to further accelerate the dormant cancer cell death to save time required for the therapeutic outcome.

Amikagel’s properties were chemo-mechanically tunable and directly impacted the outcome of tumor dormancy or relapse. Exposure of dormant spheroids to weakly stiff and adhesive formulation of Amikagel resulted in significant relapse, mimicking the response to changes in extracellular matrix around dormant tumors. Relapsed cells showed significant differences in their metastatic potential compared to the cells that remained dormant after the induction of relapse. Further, the dissertation discusses the use of Amikagels as novel pDNA binding resins in microbead and monolithic formats for potential use in chromatographic purifications. High abundance of amino groups allowed their utilization as novel anion-exchange pDNA binding resins. This dissertation discusses Amikagel formulations for pDNA binding, metastatic cancer cell separation and novel drug discovery against tumor dormancy and relapse.
ContributorsGrandhi, Taraka Sai Pavan (Author) / Rege, Kaushal (Thesis advisor) / Meldrum, Deirdre R (Thesis advisor) / Stabenfeldt, Sarah (Committee member) / Caplan, Michael (Committee member) / Tian, Yanqing (Committee member) / Arizona State University (Publisher)
Created2016