Britta Bergstrom and Dr. Heidi Vollmer-Snarr, Chemistry and Biochemistry
The purpose of my project was to evaluate how effective a certain class of organic chemical compounds, known as fluorescent folate bis-retinoid bioconjugates, is for use as chemotherapy agents. An important part of my research involved developing techniques for the growth and maintenance of healthy cancer-cell cultures. I focused especially on the use of a new kidney cancer cell culture, because kidney cancers are hypothesized to be especially susceptible to chemotherapy with folate bioconjugates. The purpose of the folate part of the bioconjugate is to direct the drug to the cancer cells, because cancer cells tend to take in more folate than normal, healthy cells do. The part of the drug that causes cell death is the bis-retinoid compound. The compound I tested is known as A2E, and is a chemical recently discovered in the eye and which is especially prevalent in people with eye disease. A2E has been found to be toxic to cells when irradiated with UV light, and thus may be connected to development of eye disease. The purpose of my research was to determine if the A2E could be activated by UV light once it had entered the cancer cells, enabling us to target cancer cells specifically, without harming normal healthy cells.
Although during my research I encountered many setbacks and difficulties, I was able to grow up cultures of kidney cancer cells. I then Added A2E synthesized by colleagues in my lab to the kidney cancer cultures. After incubating the cells with the A2E, the cultures were irradiated with a UV light. Cell counts were then performed to determine if the irradiated A2E did, in fact, kill the cells. Setup conditions for this assay are shown below. DMSO was used as a control because the A2E was dissolved in a DMSO solution, and DMSO is not generally toxic to cells at low levels.
It appears that the 10 uM A2E was most effective at killing the cells according to cell concentration and cell viability. Considerably more cells were killed in the well containing 10mM A2E than in the control wells containing only cells. However, the well containing 1.5 ul DMSO had an unexpectedly high death rate. This might be because of chance, but this well was also in the same location on the well plate as the well containing 10 uM A2E. In spite of this, all wells should have about the same exposure to light irradiation. Also, the cell counts were low because of dilution, making these numbers less reliable. However, it does appear that A2E is effective in killing the cells after irradiation.
More research needs to be done in this area, including more assays to provide consistent results showing that A2E does kill kidney cancer cells. It will also be useful to determine the concentration at which A2E is most effective. The next step will be to test A2E conjugated to folate and determine if it selectively kills cancer cells and not normal healthy cells.