Do you mean ending them in power, or wiping out every living member? Here are some examples of using assassination to remove a dynasty from power, but there were familial survivors of the purges.

In Rome the Julio-Claudian Dynasty was ended when Nero committed suicide just ahead of the assassins. The same for the Antonine Dynasty with the assassination of Commodus. More recently, the Soviets liquidated the Romanov dynasty in Russia.