Harvey Pekar, whose autobiographical comic book series American Splendor portrayed his unglamorous life with bone-dry honesty and wit, was found dead at his Cleveland home early Monday, authorities said. He was 70. The cause of death was unclear, but Pekar suffered prostate cancer, asthma, high blood pressure and depression. Pekar took a radically different track from the superhero-laden comics that had dominated the industry. He instead specialized in the lives of ordinary people, chronicling his life as a file clerk in Cleveland. Pekar never drew himself but depended on collaborations with artists, most notably his friend R. Crumb, who helped illustrate the first issue of the ironically titled American Splendor, published in 1976. It was made into an acclaimed 2003 film starring Paul Giamatti as Pekar. "Harvey was one of the most compassionate and empathetic human beings I've ever met," Giamatti said in a statement. "He was a great artist, a true American poet, and there is no one to replace him."