Both have Japanese boygroups in it who have to fight against sketchy criminal groups to keep their group safe. They both have a bit of a ridiculous premise although JAM goes way further with it.
It is similar in a way that both drama's are a narrative of an actor who goes from a nobody to a legend overnight, however as JAM drama is a bit comedic and rolls on a petty-fictional-plot, they both have Thearetical Concepts.