It surged 2 3\/4 to 6 on volume of more than 1.7 million shares after the company agreed to be acquired by Japan 's Chugai Pharmaceutical for about $ 110 million -- almost double the market price of Gen - Probe 's stock .	<arg1> $ 110 million </arg1> <rel> is </rel> <arg2> almost double the market price of Gen - Probe 's stock </arg2>	1