100 hours is recommended, and not required, so you can still apply and get accepted with 50-60 hours. However, any time a school recommends you to do something and you don't do it, it would hinder your chances slightly. For example, if you and other applicants had similar GPA/DAT/ECs/LoRs, and other people had the recommended hours, they would get the interview rather than you. If UIC is your first choice, get the 100 hours. If it's not, don't worry about it.