Well seeing that its from the Japanese Arseusu (I think that's how it was before the Romanized version came out), and I'm sure Japanese people don't pronounce the 'se' as 'kay'.
Also, in standard English, the 'c' in 'ce' is soft, because it is followed by an 'e'. A 'c' followed by e or i is a soft one, and a 'c' followed by a, o, or u is a hard one.
O_o
So it think its Arsay-uhs.