From the main menu, go to Features, then to "Codes. Input the following:

2K Sports team - Input "2ksports" as as a cheat code and you will unlock the 2K Sports team.
2K Sports China team - Input "2kchina" as as a cheat code and you will unlock the 2K Sports China team.
NBA 2K development team - Input "nba2k" as as a cheat code and you will unlock the NBA 2K development team.
Visual Concepts team - Input "vcteam" as as a cheat code and you will unlock the Visual Concepts team.
Retro Air Jordan shoes - Input "23" as as a cheat code and you will unlock the Jordan Sneaker Collection.
ABA ball - Input "payrespect" as as a cheat code and you will unlock the ABA ball.