The best you can do is to buy and install a usb 3.0 expansion card. You should also be able to extend those ports to your front panel through a bay adapter. If your case manufacturer makes usb 3.0 ports for your case this may also be something to look at.
Your existing usb 2.0 ports cannot be upgraded. When the USB 3.0 standard was introduced it added 5 connections/cables. The cables are heavier, most of the connections are bigger (type A plug is the only connection still the same size but has 5 additional pins for the extra cabling).