PITTSBURGH — Joseph Horne Co. has hired the investment banking firm of CS First Boston Corp. to explore the possible sale, merger or refinancing of the independently owned department store chain.

Horne, which operates 10 units in the Pittsburgh area, went through a restructuring in December 1991, with some of its lenders converting their debt to equity. Annual sales are between $200 million and $250 million, and operations are currently near break-even, according to a spokesman.

In a statement, Michael L. Pulte, Horne’s chairman, said there have been “persistent, unsolicited inquiries” by a number of major retailers expressing an interest in the company.