PACLI = park
+
TAXEL = taxi
Separate paclitaxel into PACLI (sounds like park) and TAXEL (sounds like taxi). Imagine that you're on the sidewalk, trying to wave down a taxi. After 10 minutes, you are now angry and put your hand out at the taxi trying to freeze it in place, saying PARK (PACLI) THE TAXI (TAXEL)!! Just like you're freezing this taxi in place, paclitaxel stabilizes microtubules by freezing them in place.

Antineoplastic
PACLI = park | TAXEL = taxi