The owner of three Honolulu office towers suffered another quarterly loss as expenses crept higher and revenue slipped during the three months ended June 30.

Pacific Office Properties Trust Inc. lost $4.2 million in the second quarter compared with a $3 million loss in the same period last year, according to a financial report filed with the U.S. Securities and Exchange Commission on Friday.

The Honolulu-based company, which owns Waterfront Plaza, Davies Pacific Center and the Pan Am Building, said those buildings were 85.1 percent leased on average as of June 30 compared with 85.8 percent at the end of March. Those percentages translate roughly to 166,000 square feet of unleased space at the end of June, up from 159,000 square feet at the end of March. Pacific Office also owns a 5 percent stake in an Arizona property.

Revenue in the second quarter slipped to $11.2 million from $11.3 million a year earlier. At the same time, expenses grew by about $1 million largely due to higher loan fees, electricity costs and administrative fees.

Pacific Office was established in 2008 by local real estate investor Jay Shidler, who contributed several buildings he owned and issued public stock in the new firm. At one time, Pacific Office owned 24 properties and aimed to acquire many more. But the U.S. economic recession that unfolded shortly after the company’s formation disrupted the plan, and Pacific Office sold or lost properties to foreclosure.

Through June 30, Pacific Office’s cumulative net loss since it was formed has grown to $249 million.

Shares of Pacific Office stock are lightly traded and the most recent sale and closing price was Aug. 2 for 9 cents. Over the last 52 weeks, shares of Pacific Office stock have closed between a low of 5 cents on Feb. 23 and a high of 36 cents on Sept. 30.