Precision Therapeutics Inc., a Pittsburgh-based oncology services company, has filed for an $80.5 million IPO. It plans to trade on the Nasdaq, with JPMorgan and Piper Jaffray serving as co-lead underwriters. Precision Therapeutics has raised around $84 million in VC funding since 1996, from firms like Adams Capital Management (39.1% pre-IPO stake), Quaker bioVentures (21.5%), TVM Capital (9.1%), Birchmere Ventures (8.8%), Stephens Group (6.5%) and Draper Triangle Ventures.