If I were you, I'd translate the whole thing as something else - something commonly used in Turkish as a flip or smartass answer to "Ne var ne yok?" because that's what "What's up?" means.
Thank you for all your explanations. But I can't find a suitable Turkish expression for that kind of question. Maybe we can mention the joke under the translation.
Bence 'ne var ne yok?', 'nasıl gidiyor?' ya da 'naber?' sorularına soğuk bir espri bulmalıyız ama benim aklıma doğru düzgün bir şey gelmiyor.