The Nasdaq rose on Wednesday, lifted by technology and biotech shares. But financials weighed down the Dow and S&P 500 on uncertainties about the Obama administration's proposed regulatory reforms and after Standard and Poor's cut debt ratings on several U.S. banks.

The Dow Jones industrial average <.DJI> dropped 7.49 points, or 0.09 percent, to close unofficially at 8,497.18. The Standard & Poor's 500 Index <.SPX> fell 1.26 points, or 0.14 percent, to end unofficially at 910.71. But the Nasdaq Composite Index <.IXIC> gained 11.88 points, or 0.66 percent, to finish unofficially at 1,808.06.

(Reporting by Rodrigo Campos; Editing by Jan Paschal)