That is a aftermarket radio. Some have a removable front to gain access to the release locks.
Often they come with two thin "keys" which slide down the sides of radio to release the locking device.
You may be able to do it with a bit of thin steel three or four inches long with a bend on the end so you can push it and about 1/4 inch wide.
Do one side at a time and ease it out with a wide flat screwdriver, then stop it from falling back in as you do the same trick on the other side.
Once out you will see the cage that sits in with bent tangs to stop cage coming loose.
If you are stuck about what I mean I can take a photo of the tools for it in my garage, but I would prefer not too.