NEW YORK — An additional 400 to 500 jobs will be eliminated at CBS Inc. this year as cutbacks are accelerated under new acting chief executive officer Laurence Tisch, network sources said in

a published report today.

The reductions are part of the company’s efforts to streamline its operations in the face of a sharp slowdown in the growth of advertising revenues, the Wall Street Journal said. The

cutbacks will affect mainly such employees as finance and management information system workers in the company’s corporate departments and in its broadcasting, publishing and record groups