Date of Graduation
Bachelor of Science in Biomedical Engineering
Bladder cancer is the 5th most common non-cutaneous human cancer in the United States. While effective methods of detecting bladder cancer are currently practiced, they are often expensive and invasive. There is a need for a noninvasive detection method that can be used in areas with few medical resources. Cell free DNA in urine is normally present only in very low concentrations. Abnormally high levels of cell free DNA in urine could be indicative of disease. This study tests the hypothesis that DNA present in urine can be used as a biomarker for bladder cancer before hematuria is seen in vivo. First, different DNA probes were compared, and SYBR green was selected as an ideal probe due to factors such as cost, safety concerns, and specificity. Second, a detection threshold of cells was determined using MB49 and MBT2 bladder cancer cell lines. Cells were lysed with either tap or DI water to determine which kind of water was more effective at creating a hypotonic solution for the cells. Two cell lines were used to determine if there was a statistical difference in the DNA detection threshold. A detection limit of between 600 cells/200μL and 300 cells/200μL was seen in both MB49 and MBT2 cells. Lastly, an in vivo study was done in which a group of mice was implanted with 75,000 MB49 cells. Urine samples were obtained for five days before implantation, as well as for seven days after implantation. Evidence of excess DNA in the urine was seen as early as four days before hematuria was observed. This study provides evidence that quantifying levels of cell free DNA is an effective method of detecting bladder cancer before hematuria is present. Future studies will determine if the DNA being detected is mammalian, and eventually, a low cost, quantitative home test will be developed to aid in early detection of bladder cancer.
Walker, Cassandra M., "Exploring Biomarkers for Point of Care Bladder Cancer Detection" (2016). Biomedical Engineering Undergraduate Honors Theses. 25.