* Initial claims, existing home sales data on tap
* Best Buy falls in premarket after results
* Futures up: Dow 8 pts, S&P 0.25 pts, Nasdaq 2.75 pts
By Chuck Mikolajczak
NEW YORK, May 22 (Reuters) - U.S. stock index futures were little changed on Thursday, ahead of data on the labor and housing markets, after the S&P 500 advanced for a third time in four sessions.
* Investors awaited weekly initial jobless claims data due out at 8:30 a.m. (1230 GMT) for signs of continuing strengthening in the labor market. Expectations call for 310,000 claims, up from the 297,000 in the previous week, which was the lowest in seven years.
* Existing home sales data for April is due later at 10:00 a.m. (1400 GMT), and will be monitored for signs of stabilization in the housing arena. Forecasts are for a rise of 2.2 percent to an annual rate of 4.68 million, after hitting a 1-1/2 year low in March.
* S&P 500 e-mini futures rose 0.25 point and were roughly even with fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average e-mini futures gained 8 points and Nasdaq 100 e-mini futures added 2.75 points.
* Best Buy Co fell 5.7 percent to $23.91 in premarket trading after the electronics retailer reported first-quarter earnings that topped expectations but revenue fell short of forecasts as domestic comparable store sales fell 1.3 percent.
* Sears Holdings Corp posted a bigger loss for the first quarter as the struggling retailer failed to arrest a fall in sales despite offering heavy discounts to woo shoppers.
* Reynolds American Inc is in active discussions to buy Lorillard Inc in a complicated, three-way transaction that could see British American Tobacco PLC take a major role to back a potential merger, according to people familiar with the matter.
* Refiner Marathon Petroleum Corp said it would buy oil and natural gas producer Hess Corp's retail business for about $2.87 billion.
* U.S. stocks rebounded Wednesday from a selloff a day earlier, with the Dow Jones Industrial Average scoring its biggest gain in a month, after minutes of the Federal Reserve's last meeting showed central bankers had discussed the eventual tightening of monetary policy but didn't decide which tools to use.
* French stocks underperformed flat equity markets elsewhere in Europe, as weak economic data weighed on France's benchmark CAC-40 index.
* Japanese stocks led a surge in Asian equities to a one-year high, after an upbeat reading on China's factory sector burnished risk appetite and blunted some of the more pessimistic views on the world's second-biggest economy. (Editing by Bernadette Baum)