* Chinese inflation hits five-yr low
* Costco, Toll Brothers post quarterly results
* Futures off: Dow 39 pts, S&P 4.5 pts, Nasdaq 6.25 pts (Adds premarket actives)
By Chuck Mikolajczak
NEW YORK, Dec 10 (Reuters) - U.S. stock index futures edged lower on Wednesday, a day after stocks staged an intraday rally to erase a decline of nearly 1.3 percent and end nearly flat.
* Stocks shook off worries about global weakness and political turmoil in Greece on Tuesday to erase sharp declines early in the session as energy and technology shares rose.
* Energy shares will likely be in focus again, as Brent crude dropped below $66 a barrel to trade just above a five-year low on supply concerns. Oil prices have been under pressure from the dollar's strength and OPEC's decision against an output cut, with Brent down more than 40 percent from its June high.
* The S&P Energy sector is the worst performing of the 10 major S&P sectors for the year and the only group in negative territory. Falling oil prices have raised concerns about earnings for energy companies, with year-end tax selling bringing additional pressure on the group.
* After climbing to its most recent record high on Friday, the S&P 500 has slipped 0.7 percent and is up 10.6 percent from its October low.
* China's inflation hit a five-year low in November, sparking hopes Beijing will move more aggressively with monetary policy easing to head off the risk of deflation in a slowing economy.
* U.S.-listed shares of GlaxoSmithKline were among the most actively traded issues on the New York Stock Exchange in premarket. Shares of the drugmaker fell 1.8 percent to $43.34 after Bank of America Merrill Lynch cut its rating on the stock to "underperform" from "neutral."
* Costco Wholesale Corp rose 0.8 percent to $144.20 in premarket trade after it reported a better-than-expected quarterly profit as increased promotions helped the warehouse club operator deal with fierce competition.
* Toll Brothers lost 0.8 percent to $34.51 before the opening bell after the homebuilder posted its quarterly results.
* Yum Brands Inc lowered its profit forecast for the year for the second time, hurt by slower-than-expected sales recovery in China following a food safety scare in July. Its shares slipped 0.5 percent to $55.55 in light premarket trade.
Futures snapshot at 8:22:
* S&P 500 e-minis were down 4.5 points, or 0.22 percent, with 159,014 contracts changing hands.
* Nasdaq 100 e-minis were down 6.25 points, or 0.15 percent, in volume of 24,966 contracts.
* Dow e-minis were down 39 points, or 0.22 percent, with 21,676 contracts changing hands. (Reporting by Chuck Mikolajczak; Editing by Chizu Nomiyama)