I emailed the exchange HitBTC and here is what they said:
Thank you for contacting the HitBTC Support Team!
The currency with the highest number of votes will be periodically added onto the exchange every 2-3 weeks.
At the moment BTSX is added to HitBTC Coin Voting.https://hitbtc.com/vote
Please do not hesitate to contact us if you have any inquiries.
SO GUYS PLEASE VOTE, NTX IS ALREADY IN THE TOP!!! Register first because your vote will be worth 10 instead of 1 that way. - robrigo