Most academics (in classical philology) use the reconstructed (or classical) pronunciation, which is based on research done in the second half of the 19th century by linguists. The word cicerone is from the Italian, and it used to be pronounced /tʃitʃɛro:ne/, but is now usually pronounced /sisɛron/ according to the dictionaries which I consulted. (There are some who believe that Latin was pronounced as is modern Italian, as there are more than a few who believe that Classical Greek was pronounced as Modern Greek is, but I do not find their arguments convincing.)

Ceci n'est pas un seing.