NEW YORK ( TheStreet) -- U.S. stock futures were signaling a mixed open for Wall Street Friday ahead of first-quarter GDP figures and earnings from Ford ( F), Chevron ( CVX), Merck ( MRK) and Procter & Gamble ( PG). European shares were slightly higher despite a downgrade of Spain's credit rating from Standard & Poor's. In Asia, Japan's Nikkei 225 index finished down 0.4% to close at 9,520.89. The index got a brief lift after the Bank of Japan said it would expand its asset-buying program. The economic calendar in the U.S. Friday includes the advance estimate of first-quarter gross domestic product at 8:30 a.m. EDT. Economists are calling for growth of 2.5%. There's also the final University of Michigan read on consumer sentiment, which is seen remaining steady at 75.7. The data is due at 9:55 a.m. Automaker Ford ( F) is expected by analysts before the bell Friday to report first-quarter earnings of 35 cents a share on revenue of $31.5 billion. Amazon.com ( AMZN), the online retailer, topped analysts' earnings estimates and said profit margins held steady. Amazon's margins in the first quarter were 1.45%, in line with the fourth quarter's 1.5%. Amazon posted earnings of 28 cents a share as revenue rose 34% to $13.2 billion, thanks in part to strong Kindle Fire sales. Analysts expected Amazon to report earnings of 7 cents a share on revenue of $12.9 billion. Amazon provided second-quarter revenue guidance, with the midpoint slightly below Wall Street estimates. Samsung Electronics posted record profit in the first quarter, fueled by a surge in Galaxy smartphones. Samsung sold more smartphones in the first three months of the year than Apple ( AAPL), The Associated Press reported, and raked in more than 70% of its operating profit from its mobile businesses. Net profit nearly doubled from a year earlier to a record 5.05 trillion won ($4.46 billion). Investigations are deepening into the potential involvement of Goldman Sachs ( GS) employees in the Galleon Group insider-trading ring, according to The Wall Street Journal. U.S. prosecutors and securities regulators are investigating whether a senior Goldman investment banker gave Galleon hedge-fund traders advance word of pending health care deals, according to people familiar with the matter, the newspaper said. The banker, whom the people identified as Matthew Korenberg, is a San Francisco-based managing director for Goldman, a senior post. Federal prosecutors in Los Angeles are looking into whether Korenberg told Galleon founder Raj Rajaratnam of acquisitions of Advanced Medical Optics and MedImmune in 2009 and 2007, respectively, Reuters said. -- Written by Joseph Woelfel >To contact the writer of this article, click here: Joseph Woelfel >To submit a news tip, send an email to: email@example.com.