Chapterhouse Dune was the last Dune book that Frank Herbert wrote and some people read the final chapter as Frank ending the series - his wife Beverly was a key part of his Dune writing process and...
No. There are no similarities between George Lucas' Star Wars and Frank Herbert's Dune. other than neither occurs on or near Earth.
That it was sinful for such a large book to be written about science fiction.
Frank Herbert died on February 11, 1986 at the age of 65.
Frank Herbert was born on October 8, 1920.