Many of the voice actors offered their physical likeness to be used in the game.
We hear protagonist Isaac Clarke speak for the first time in Dead Space 2. Gunner Wright, Isaac's scream actor from the first game, filled in the role.
Lyari Limon did not return to voice Nicole Bernnan, and so Tanya Clarke was brought in to replace her. Because Limon did not grant permission to reuse her likeness, Nicole's appearance was slightly altered to closer resemble Tanya Clarke.
There is a 1991 movie called Dead Space. It's description is "a deadly virus is taking over a space station revolving around Saturn". It stars Bryan Cranston. Dead space 2 takes place in a space station orbiting Saturn. This could be an obvious reference to the movie.