Spawn is an iconic American comic book character created by Todd McFarlane. A licensed Japanese Manga adaptation of the Spawn story was written for publication in Japan. It has also been released in an English translation, allowing American readers to get their first taste of this character written and drawn in the Japanese style. The entire story is 600 pages long, representing a significant effort to adapt the Spawn mythology, as opposed to some smaller, one-off manga and anime-styled projects that have been done with other comic characters.
Efforts have also been made to convert the superhero team, the X-men, into manga and anime-styled work. "X-men: Misfits" was a co-production effort between Marvel and Del-Rey to bring the Japanese style to the X-men characters. Unlike the Spawn title, this comic was originally written in English and produced for the English market. This prevented some of the problems that can arise with translations, while still playing to the crowd that is hungry for books in these particular styles, but featuring more familiar characters.
Anime is the Japanese animation style, adapted from manga, which is similar to American comic books. American comic book characters have been made into cartoons and movies for decades now. This potential growth is something that comic book companies consider frequently. The American comic book industry has another growth option as they can release standard animation projects, featuring popular characters in the anime style. Some examples of anime-styled cartoons are "Batman: Gotham Knight" from DC Comics and "Wolverine Anime" from Marvel.
Many artists who work on traditional American comic books have been influenced by the Japanese art styles. People like Seth Fisher brought a certain amount of Japanese influence to titles like "Fantastic Four." Frank Miller is one of the most important comics artists of all time and his work features Japanese stylistic elements that clearly show how American comic books have been shaped by Japanese style. Some of Miller's work on "Daredevil," "Wolverine" and even "Sin City" reveal this influence.