If you don't have NBA 2K15 profile in Nvidia Inspector then add it by clicking little star button and then add nba2k15.exe process to just created profile
Once the profile is created set in Nvidia Inspector:
Antialiasing - Transparency Supersampling to "2x Sparse Grid Supersampling", "4x Sparse Grid Supersampling" or "8x Sparse Grid Supersampling" depending on your personal taste
and if you want some antialiasing then set
Antialiasing - Mode to "Override any application setting"
Antialiasing - Setting to something bigger like 32x CSAA
My current Nvidia Inspector settings:


Ok, now screenshots. This is how game looked before:

And this is how game looks after with 2x Sparse Grid Supersampling:

with 4x Sparse Grid Supersampling:

and with 8x Sparse Grid Supersampling:

Performance hit is minimal (after tweaks still constant 60 fps) and imo it looks much better.
Edit: Updated with new info and screenshots.