US stock markets to watch Yellen, GDP estimate By: CNBC.com News April 30, 2014 at 05:02 AM EDT U.S. stock index futures traded lower on Wednesday, with investors cautious ahead of the FOMC conference and the first estimate of Q1 growth. Read More >> Related Stocks: Gsk Plc ADR Novartis Ag ADR Sentinelone Inc Cl A Thomson Reuters Corporation Time Warner Time Warner Cable