Lauren has mainly worked in television, appearing in shows such as CSI and Hawaii Five-0.
Speaking to The Hollywood Reporter, Franco said: "Sal Mineo himself was an extraordinary and super complex guy. People know him for Rebel Without A Cause, but he was technically the first actor who came out of the closet. He was very brave."
The Howl actor-turned-director optioned the rights to a biography about Oscar-nominated Mineo last year.
Mineo received the nomination for his supporting role alongside James Dean and Natalie Wood in 1955's Rebel Without A Cause, but also received a second nomination for Exodus five years later at the age of 21. He had started to salvage his career before being stabbed to death at the age of 37.
Franco, who won a Golden Globe for playing Mineo in a 2001 television film, has denied that he will star in Sal himself.
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