A subsidiary of billionaire Patrick Soon-Shiong’s Culver City health care company NantWorks and a San Diego pharmaceutical company are jointly investing $100 million to develop cancer therapies.

NantBioScience Inc. announced Thursday that it is joining with Sorrento Therapeutics on a joint venture that will develop treatments for cancers that have not been treated successfully so far. NantBioScience will have a 60 percent stake in the venture.

“We are committing significant resources to the development of novel and innovative cancer therapies,” Soon-Shiong said in a statement. “Through this joint venture and the other ongoing collaborations we have with Sorrento, we are focused on transforming cancer therapy as we know it today.”

In May, NantWorks’ pharmaceutical subsidiary NantPharma acquired Sorrento’s Igdrasol Inc. division, which also develops cancer drugs, for $1.3 billion.

Soon-Shiong’s NantWorks divisions have been gaining momentum lately. Health care IT unit NantHealth sold a 10 percent stake to Allscripts Healthcare Solutions Inc. last month for $200 million. The deal valued NantHealth at $2 billion and may be one of the last steps before Soon-Shiong takes the company public.

He told the Business Journal last month that he expects an IPO by the end of the year.