U.S. stocks rose on Wednesday as a broker upgrade of Caterpillar lifted big manufacturers, while biotechnology shares got a lift from better-than-expected results from Gilead Sciences.

Positive comments from company executives about the state of the global economy after a mixed bag of first-quarter results offset recent pessimism about the state of corporate profits.

Caterpillar Inc was the Dow's biggest boost, surging 8.6 percent to $34.08, after JP Morgan upgraded the construction equipment maker due to its improved balance sheet and liquidity.

Gilead Sciences Inc jumped 7.5 percent to $47.02 after quarterly profit beat estimates on increases sales of its drugs to treat the virus that causes AIDS.

Boeing Co boosted the Dow after the planemaker lowered its full-year outlook but the range was still above Wall Street's expectations, according to Reuters Estimates. Its net profit narrowed as the economic slowdown hurt orders. Its shares were up 2 percent at $37.31.

The market is looking ahead here to eventual economic stabilization and recovery and ignoring what happened in the first quarter as history, even when it's worse than expected, said Tim Ghriskey, chief investment officer of Solaris Asset Management in Bedford Hills, New York.

A little bit (of positive news) from some companies in their guidance where the tone is certainly not as bad -- the tone is cautious but optimistic.

Home builders rose after data showed the prices of single-family homes rose in February. The Dow Jones home builders index <.DJUSHB> jumped 4.6 percent, and Pulte Homes Inc
gained 4.2 percent to $11.52.

The Dow Jones industrial average <.DJI> rose 56.87 points, or 0.71 percent, to 8,026.43. The Standard & Poor's 500 Index <.SPX> gained 6.69 points, or 0.79 percent, to 856.77. The Nasdaq Composite Index <.IXIC> was up 22.02 points, or 1.34 percent, at 1,665.87.

(Reporting by Leah Schnurr, additional reporting by Edward Krudy; editing by Jeffrey Benkoe)