Cameo had been around for well over a decade - making good, funky music - when "Word Up" hit the radio airwaves in 1986. For some reason, this is the song that made them huge - a crossover sensation to mainstream radio. Maybe it was the non-stop old-school funk, which was gaining in prominence with the rise of hip-hop. Maybe it was the timely horn sound. Maybe it was the red codpiece that Larry Blackmon wore throughout the video, which also got heavy MTV airplay.
I encourage you to listen to this twice. See if you can catch the speed-enhanced sample from the theme song for The Good, The Bad, and the Ugly. Also, see if you can catch LeVar Burton, at the time best known for his part in Roots and as the host of Reading Rainbow, as the funkiest cop alive.