Stocks: Investors cautious ahead of Fed

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NEW YORK (CNNMoney) -- Stocks were headed for a slight dip at the open Wednesday as investors await word from the Federal Reserve about whether it will act to spur the sluggish U.S. economy.

Dow Jones industrial average (INDU), S&P 500 (SPX) and Nasdaq (COMP) futures were slightly lower ahead of the opening bell. Stock futures indicate the possible direction of the markets when they open at 9:30 a.m. ET.

The Federal Reserve concludes its two-day policy meeting Wednesday afternoon, and investors are hoping the central bank will announce new action to spur the economy -- a move being dubbed "Operation Twist".

In addition to the Fed, investors will continue to monitor the developing situation in debt-stricken Greece.

Evangelos Venizelos, the Greek finance minister, carried on two days of conference calls with the International Monetary Fund, European Council and European Central Bank.

What a Greek default would mean

The talks ended without any definitive deal but Venizelos is due to carry on further discussions this weekend in Washington, D.C., where the IMF and World Bank are holding their annual meetings, and the so-called troika is expected to head to Athens next week.

Stocks erased most of the day's gains Tuesday, as investors grew wary about Greece's situation.

Economy: The National Association of Realtors will release its August existing home sales data after the opening bell. Economists surveyed by Briefing.com expect sales to have edged up to an annual rate of 4.70 million in August from 4.67 million in July.

Companies: General Mills (GIS, Fortune 500) reported better-than-expected earnings and reaffirmed its guidance.

Retailer Bed Bath & Beyond (BBBY, Fortune 500) will post results after the market close.

Shares of beer giant Anheuser Busch Inbev (BUD) will be closely watched after U.K. brewer SABMiller (SBMRY) announced a deal to buy Australian beer company Fosters for just over $10 billion.

After the market closed Tuesday, software company Oracle (ORCL, Fortune 500) reported better-than-expected sales and profit. Shares rose more than 4% in premarket trade.

Also after the bell Tuesday, software maker Adobe Systems (ADBE) reported third-quarter earnings that beat estimates and it raised its revenue guidance. Shares jumped nearly 7% in premarket trade.

World markets: European stocks were lower in morning trading. Britain's FTSE 100 (UKX) shaved 1%, the DAX (DAX) in Germany lost 1.6% and France's CAC 40 (CAC40) fell 1.4%.

Asian markets ended mixed. The Shanghai Composite (SHCOMP) jumped 2.7%, the Hang Seng (HSI) in Hong Kong lost 1% and Japan's Nikkei (N225) added 0.2%.

Currencies and commodities: The dollar gained against the euro and the British pound but lost ground against the Japanese yen.

Oil for November delivery slipped 97 cents to $85.95 a barrel.

Gold futures for December delivery fell $13 to $1,796.10 an ounce.

Bonds: The price on the benchmark 10-year U.S. Treasury edged up, pushing the yield down to 1.93% from 1.94% late Tuesday.