So, "sequel" as a name, as opposed to "ess-cue-ell" is pretty universally used in English. Most people who use it call the Microsoft RDBMS "sequel server" not "ess-cue-ell server" and I hear "sequel" slightly more than spelling out the acronym these days. The UK does tend to prefer to make a word out of an acronym though, so we tend to say things like OS (Operating System) as "oss" not "oh-ess". This led me in a conversation once to only realise at the end that the guy was talking about "RTOS" (which I had only ever read, and used the more American "AR-TEE-OH-ESS") when he was saying "are-toss".
Edited to clarify we are talking about English usage because apparently, someone speaking French down voted me because French is not English..