* Weekly jobless claims on tap
* Futures up: Dow 40 pts, S&P 500 5.5 pts, Nasdaq 8.25 pts
NEW YORK, Sept 3 (Reuters) - U.S. stock index futures rose on Thursday after a four-day losing streak and ahead of data expected to show initial jobless claims continue to fall.
* Chinese stocks gained nearly 5 percent as mining shares shined after a top regulator assured investors the country's market was healthy. Chinese issues have rattled equity investors around the world with recent steep falls.
* The jobless claims data are coming one day before key monthly payroll figures and after data showed Wednesday that more private-sector jobs were lost in August than forecast.
* "You need a bit of a downward momentum stopper and (the jobs number) could have that effect," said Rick Meckler, president of investment firm LibertyView Capital Management in Jersey City, New Jersey.
"The selling seems to have run most of its course, so a number that's considered good or even okay would both be pretty positive for the market."
* U.S. retailers will report monthly sales, indicating the health of the back-to-school selling season. Investors are watching whether cash-strapped consumers are loosening their purse strings in a prelude to the Christmas period.
* S&P 500 futures rose 5.5 points and were above 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 futures gained 40 points, and Nasdaq 100 futures added 8.25 points.
LibertyView's Meckler said low trading volumes ahead of the U.S. Labor Day holiday have increase volatility, and he expects increased volumes next week to smooth the market.
* Japan's Nikkei average dropped 0.6 percent as export shares fell on fears over the strength of the U.S. labor market, but European equities were broadly higher after a three-session losing streak.
* On the M&A front, Dainippon Sumitomo Pharma Co Ltd, Japan's No. 7 drugmaker by revenues, agreed to buy U.S. drugmaker Sepracor Inc for $2.6 billion. The deal will give the Japanese firm a big, local sales force in the world's largest drugs market.
* U.S. crude oil futures rose 1.6 percent to above $69 a barrel, gaining ground a day after data showed U.S. gasoline stocks fell sharply, boosting expectations that demand will be revived in the United States.
* Weekly initial jobless claims are due at 8:30 a.m. EDT, while ISM non-manufacturing data for August is set for 10:00 a.m. Economists look for 560,000 claims versus 570,000 a week ago.
* Economists polled by Reuters look for a loss of 225,000 jobs in Friday's nonfarm payrolls report for August.
* U.S. stocks retreated Wednesday after the ADP Employer Services report showed more private-sector job losses in August than forecast.