* Netflix tumbles as U.S. subscribers drop
* Union Pacific, Phillip Morris jump after results
* Morgan Stanley beats profit estimates
* UnitedHealth drops on revenue warning
* Indexes down: Dow 0.39%, S&P 0.22%, Nasdaq 0.47% (Updates to early afternoon)
By Medha Singh and Uday Sampath Kumar
July 18 (Reuters) - Wall Street's main indexes were set for their third day of losses on Thursday, as Netflix reported a surprise fall in U.S. subscribers in a downbeat start to results from high-growth companies.
Shares of the streaming pioneer tumbled 11.1% to their lowest since late-January at $321.84, as the company also missed targets for new subscribers overseas at a time when it has staked its future on global expansion.
Losses in Netflix triggered a 1.58% fall in the communication services sector, one of the best-performing S&P sectors so far this year.
Technology giant Microsoft Corp slipped 0.8% ahead of its results after markets close.
"The stock market seems to be running out of energy," said John Augustine, chief investment officer of Huntington Private Bank in Columbus, Ohio.
"Earnings have met expectations but companies are being cautious about future quarters, which is something that's not able to keep the S&P 500 above the 3,000 level."
As second-quarter earnings rolled in this week, the three main Wall Street indexes retreated slightly from record highs and are set for their steepest weekly fall in seven weeks.
Investors are looking for concrete developments in trade talks between the United States and China, while they await the Federal Reserve's policy meeting at the end of July where the central bank is widely expected to cut interest rates.
Treasury Secretary Steven Mnuchin said U.S. and Chinese officials will hold a telephone call later on Thursday that could pave the way for further in-person trade talks.
At 12:08 p.m. ET, the Dow Jones Industrial Average was down 105.12 points, or 0.39%, at 27,114.73 and the S&P 500 was down 6.64 points, or 0.22%, at 2,977.78. The Nasdaq Composite was down 38.16 points, or 0.47%, at 8,147.04.
Among positive earnings reports, tobacco company Philip Morris climbed 8.3% after raising its full-year profit outlook, while railroad operator Union Pacific Corp jumped 4.2% after reporting a profit beat.
International Business Machines Corp rose 3.8% as its quarterly profit beat on strong growth in its high-margin cloud business.
Morgan Stanley rose 0.7% after posting a better-than-expected quarterly profit and wrapped up earnings from big U.S. banks. The bank-subsector was up 0.73% after three days of losses.
Profits for S&P 500 companies is expected to rise 0.6% this year, according to Refinitiv IBES data. Until Wednesday, there were expectations of a dip in earnings.
UnitedHealth Group Inc slipped 2.5% as the insurer said 2019 revenue would not hit its original target on the conference call.
Declining issues outnumbered advancers for a 1.40-to-1 ratio on the NYSE and for a 1.21-to-1 ratio on the Nasdaq.
The S&P index recorded 20 new 52-week highs and four new lows, while the Nasdaq recorded 41 new highs and 74 new lows. (Reporting by Medha Singh and Uday Sampath in Bengaluru; Editing by Sriraj Kalluvila and Anil D'Silva)