US STOCKS-Wall St rally fades ahead of key jobs data
* ECB hints at prolonging bond-buying program
* Nasdaq briefly turns negative, Apple biggest drag
* Joy Global falls after slashing full-year forecast
* Indexes up: Dow 0.38 pct, S&P 0.40 pct, Nasdaq 0.03 pct (Updates to open)
By Tanya Agrawal
Sept 3 (Reuters) - Wall Street's early rally faded in afternoon trading on Thursday as investors appeared to turn cautious ahead of a key U.S. jobs report, which is expected to figure in the Federal Reserve's decision on when to lift interest rates.
The market rose sharply earlier in the day after European Central Bank chief Mario Draghi hinted at more stimulus measures in the wake of lower oil prices, weaker growth in China and a strengthening euro.
Draghi's remarks come a day ahead of the monthly U.S. nonfarm payrolls data, which is expected to show that the economy added 220,000 nonfarm jobs in August, up from 215,000 in July.
The Fed, which meets on Sept. 16-17, has said it will raise rates when it sees sustained economic recovery. But while the labor market has strengthened, inflation remains below the Fed's 2 percent target. Continuación...