Before the bell: Investors concern about Italy

U.S. stocks were headed for another weak day Tuesday, as fears about the eurozone debt crisis spreading to Italy rattled investors' nerves.

Economy: The U.S. trade balance figures for May came in at $50.2 billion - far larger than a revised $43.6 billion in April. The trade deficit was also wider than the $44 billion expected by economists.
World markets: European stocks fell in morning trading. Britain's FTSE 100 shed 1.6%, the DAX in Germany retreated 2.0%, and France's CAC 40 tumbled 2.4%.
Asian markets ended the session sharply lower. The Shanghai Composite dropped 1.7%, the Hang Seng in Hong Kong tumbled 3.1% and Japan's Nikkei lost 1.4%.
Companies: After the closing bell Monday, Alcoa (AA, Fortune 500) reported a larger than expected gain in second-quarter sales but investors weren't impressed.
While Alcoa beat on sales, earnings were only in line with recently lowered analyst estimates. Shares slid more than 1% in premarket trading.
Bank shares were also under pressure, with Bank of America (BAC, Fortune 500), Wells Fargo (WFC, Fortune 500) and Citigroup (C, Fortune 500) all off a little more than 1%.
Shares of tech firm Microchip (MCHP) slumped 5.7%, after the company lowered its earnings guidance.
Shares of Novellus Systems (NVLS) fell 5%, after the company delivered disappointing quarterly results and guidance.