updated 05/02/2010 AT 9:00 PM ET
•originally published 05/02/2010 AT 10:00 PM ET
One year after losing his brother Adam to a brain tumor, David Cook returned to a place – and a race – close to his heart.
In 2009, the American Idol winner served as grand marshal for the Race For Hope, which benefits the National Brain Tumor Society and Accelerate Brain Cancer Cure, despite his brother’s passing just one day before.
Returning to the annual 5K in Washington, D.C., on Sunday, Cook tells PEOPLE, “I came back because the cause is important to me and my family, as well as countless others. Brain tumors and brain cancer continues to be one of the most under-funded diseases.”
So the singer made sure to do his part, raising $140,000 with his team and fans as part of the $2.3 million the race earned overall.