Simplify the following text for a Grade 10 native English-speaking person.
Original: In 2001 he was awarded the Nobel Prize in Physiology or Medicine with Leland Hartwell and Sir Paul Nurse for their discoveries regarding cell cycle regulation by cyclin and cyclin-dependent kinases .
Simplified: In 2001 he was awarded the Nobel Prize in Physiology or Medicine with Leland Hartwell and Paul Nurse for their work on cell division .