Educating a friend

[escherzo.livejournal.com]

So, someone I know has posted a few times about a "tranny party" themed college party she went to. I have yet to think of any response to it but I feel like I should say something because a. it's making me kind of uncomfortable and b. "tranny party"? really not okay.

Any advice on how to explain exactly what the problem is there without coming off as rude? I'm not sure quite how to approach it.