Third Place: Arun Dutta, 9th Grade
“An Inhibitor for Cells' Response To DNA Damage” (14001)
Category: Cellular and Molecular Biology
Region: Western Albemarle High School, Charlottesville
Abstract: When a cancer is treated with radiation, the radiation cuts through the cell’s DNA. The desired result is that the cell will replicate the damaged DNA and thus hurt the cancer. But a cellular complex called Tip60 helps repair the damage. Thus the cancer cells are not damaged. So, we must find some way to stop Tip60 from doing its job. This experiment tests two chemicals to see how well they inhibit Tip60 activity: anacardic acid and garcinol. These two chemicals are known to inhibit other Histone Acetyl Transferases (HATs), and we will first test if they inhibit Tip60 acetyl transferase activity. If they do so, then we will test whether together they inhibit Tip60 even more.
To measure Tip60 activity, we used an ELISA HAT assay. We chose this procedure because of its brief completion time (4-5 hours) and its ability to give results in numbers. First, histone peptide H4 in the wells was briefly acetylated with Tip60 enzyme with or without the chemicals. Acetylation was measured by the addition of anti-acetyl-Lysine and Goat Anti-Rabbit IgG-HRP conjugate. TMB substrate mixture was next added to the wells. After the reaction was stopped, absorbance was measured at 450 nm with a spectophotometer.
After testing, it was clear that anacardic acid and garcinol inhibit Tip60 with anacardic acid inhbiting more than garcinol does. Anacardic acid decreases Tip60 activity to 50% at a much lower concentration than garcinol. Both these chemicals have enormous potential for use in treating cancer with radiation.
Monday, April 14, 2008
at 8:50 AM