(CDK8/CDK19) Scientists raise warning over drugs targeting key cancer mechanism

Medical News
 January 12, 2016

Scientists have expressed concerns about developing drugs against two molecular targets that had been considered highly promising, after finding that specifically blocking their function adversely affected normal body systems.
The molecular targets CDK8 and CDK19 - members of an important family known as kinases - have a key role in turning on cancer-causing genes and have been implicated in the development of several cancers, including those of the bowel and blood.
But researchers found that specifically blocking the function of CDK8/19 - using highly potent and selective prototype drugs - could not be tolerated in animal studies at doses high enough to have convincing anti-cancer activity in laboratory models of those diseases.
They have shown that blocking CDK8/19 causes too many effects on genes involved in normal cellular function to be viable as cancer treatments - specifically when given continuously at doses needed to block growth of bowel and blood cancers in the lab.....