* Futures: Dow down 17 pts, S&P off 2.5 pts, Nasdaq up 0.25 pts
By Tanya Agrawal
Nov 8 (Reuters) - U.S. stock index futures were slightly lower on Wednesday, a day after the Dow closed at a record high for the fourth straight day, as investors closely watch Republican efforts to pass the tax bill.
* Shares of Snapchat operator Snap were down 7.2 percent in choppy premarket trading after China's Tencent took a 12 percent stake. The stock had fallen nearly 20 percent earlier, a day after Snap reported much-slower-than expected advertising revenue and user growth.
* Investors are nervous about the potential outcome of a Republican plan to cut corporate taxes, unveiled last week. As well as slashing the corporate rate to 20 percent from 35 percent, the bill would eliminate many tax breaks and is expected to face opposition from interest groups.
* Senate Republican leaders are considering a one-year delay in the implementation of a major corporate tax cut to comply with Senate rules, The Washington Post reported on Tuesday, citing unidentified sources.
* Republicans are yet to score a major legislative win since Trump took office in January, even though the party controls both chambers of Congress as well as the White House.
* The S&P 500 ended marginally lower on Tuesday after a disappointing profit forecast from Priceline and a drop in financials.
* The S&P has risen about 21 percent since the election of President Donald Trump, partly on the back of his promises to cut taxes and other business-friendly measures.
* The U.S. 2-to-10-year Treasury yield curve hit its flattest in a decade on Tuesday, which at a time when the Federal Reserve is hiking rates, analysts say, is a sign of investors fretting over the sustainability of economic growth and inflation in the world's biggest economy.
* The market is also keeping an eye on Trump's Asia trip after he used some of his toughest language yet to warn North Korea against the development of its nuclear weapons.
* With third-quarter earning season winding down, earnings for the quarter are expected to have climbed 8 percent, compared with expectations of a 5.9 percent rise at the start of October, according to Thomson Reuters I/B/E/S.
* Take-Two Interactive Software rose 10.3 percent after the videogame maker gave a stronger-than-expected revenue forecast for the holiday quarter.
* Regeneron Pharmaceuticals was up 3.6 percent, while Humana rose 3 percent after the drugmakers reported better-than-expected quarterly profits.
Futures snapshot at 7:08 a.m. ET (1108 GMT):
* Dow e-minis were down 17 points, or 0.07 percent, with 20,575 contracts changing hands.
* S&P 500 e-minis were down 2.5 points, or 0.1 percent, with 136,251 contracts traded.
* Nasdaq 100 e-minis were up 0.25 points, or 0 percent, on volume of 22,084 contracts. (Reporting by Tanya Agrawal; Editing by Arun Koyyur)