Some of the proceeds from sales of the vanity plate would go to the One Fund Boston.
Rob Watson and Natasha Wodak are among the favorites to win the men's and women's races.
The 17-year-old Cain took nearly a second off the previous mark.
Victoria Mitchell is trying to raise money as she prepares for the 2016 Olympics.
The Tennessee runner hopes to improve on last year's Houston Marathon time of 2:18 this weekend.
Jamie Young will take on the 26.2-mile journey to raise money for the Shamrock Foundation.
The annual race through the British capital will be Farah's first time racing the 26.2-mile distance
The high school senior finishes on the podium at the NYC Gotham Cup
The teenager completed 13 half marathons in 2013.
Rynn Berry was found in a New York City park after collapsing on New Year's Eve.