US STOCKS-S&P 500, Dow scale new peaks; Nasdaq hit by Facebook

(For a Reuters live blog on U.S., UK and European stock markets, click LIVE/ or type LIVE/ in a news window)

* Snap tumbles on Apple tweak, drags social media giants lower

* AmEx rises on profit beat, boosts Dow

* Indexes: Dow up 0.33%, S&P up 0.05%, Nasdaq down 0.39% (Updates to open)

By Shreyashi Sanyal and Devik Jain

Oct 22 (Reuters) - The Dow and the S&P 500 hit record highs on Friday following positive earnings from American Express, while the Nasdaq was pressured after social media giants including Facebook tumbled on Apple privacy tweak worries.

The benchmark index hit an intraday record for the second straight session and was set for weekly gains of 1.8%, extending a bullish run for the third consecutive week.

"The S&P is making new highs while we're in the middle of the supply chain issue so the market is telling you 'I know about this and I'm not worried'," Eric Diton, managing director of investment advisory firm The Wealth Alliance, said.

"We're still in a very low interest rate environment, coupled with a global economic recovery that is going to have fits and starts and a still accommodative Federal Reserve ... that is not the input for a major bear market."

Nine of the 11 major S&P 500 sector indexes were higher in the first hour of trading, while the communication services sector fell over 2% as it was hit by a slump in social media giants.

American Express Co rose 5.1%, the biggest boost to the Dow Jones Industrial Average, as it beat profit estimates for the fourth straight quarter.

Intel Corp tumbled 10.8% as it missed third-quarter sales expectations, while its chief executive officer pointed to shortages of chips holding back sales of its flagship processors.

Supply chain worries, inflationary pressures and labor shortages have been at the forefront of the third-quarter earnings season. Analysts expect S&P 500 earnings to rise 34.8% year-on-year, with just over 100 companies having reported so far, according to data from Refinitiv.

Some analysts, however, said such worries will only have a temporary impact on earnings from mega-cap technology and communication companies this reporting season.

Facebook Inc fell 5.0% and Twitter Inc lost 3.2% after Snap Inc said privacy changes by Apple Inc on iOS devices hurt the company's ability to target and measure its digital advertising.

Snap plummeted 22.9% on the news and cast doubts over quarterly reports next week from Facebook and Twitter, social media firms that rely heavily on advertising revenue.

Apple edged up 0.2%. Other growth stocks including Tesla Inc and Netflix Inc also rose.

At 10:02 a.m. ET the Dow Jones Industrial Average was up 118.92 points, or 0.33%, at 35,722.00, the S&P 500 was up 2.48 points, or 0.05%, at 4,552.26, and the Nasdaq Composite was down 58.83 points, or 0.39%, at 15,156.87.

Mattel Inc gained 0.8% after it raised its 2021 sales forecast on Thursday, saying it would overcome industry-wide shipping disruptions.

Data showed U.S. business activity accelerated in October, as COVID-19 infections subsided, though labor and raw material shortages held back manufacturing.

Advancing issues outnumbered decliners for a 1.81-to-1 ratio on the NYSE, while declining issues outnumbered advancers for a 1.43-to-1 ratio on the Nasdaq.

The S&P index recorded 74 new 52-week highs and no new low, while the Nasdaq recorded 90 new highs and 63 new lows. (Reporting by Shreyashi Sanyal and Devik Jain in Bengaluru; Editing by Arun Koyyur, Sriraj Kalluvila and Shounak Dasgupta)