STK33 kinase inhibitor BRD-8899 has no effect on KRAS-dependent cancer cell viability

Approximately 30% of human cancers harbor oncogenic gain-of-function mutations in KRAS. Despite interest in KRAS as a therapeutic target, direct blockade of KRAS function with small molecules has yet to be demonstrated. Based on experiments that lower mRNA levels of protein kinases, KRAS-dependent c...

Full description

Bibliographic Details
Main Authors: Luo, Tuoping, Masson, Kristina, Jaffe, Jacob D., Silkworth, Whitney, Lee, Nathan Ross, Scherer, Christina A., Scholl, Claudia, Frohling, Stefan, Stern, Andrew M., Schreiber, Stuart L., Golub, Todd R., Carr, Steven A
Other Authors: Massachusetts Institute of Technology. Engineering Systems Division
Format: Article
Language:en_US
Published: National Academy of Sciences 2012
Online Access:http://hdl.handle.net/1721.1/72564
https://orcid.org/0000-0002-7203-4299
Description
Summary:Approximately 30% of human cancers harbor oncogenic gain-of-function mutations in KRAS. Despite interest in KRAS as a therapeutic target, direct blockade of KRAS function with small molecules has yet to be demonstrated. Based on experiments that lower mRNA levels of protein kinases, KRAS-dependent cancer cells were proposed to have a unique requirement for the serine/threonine kinase STK33. Thus, it was suggested that small-molecule inhibitors of STK33 might have therapeutic benefit in these cancers. Here, we describe the development of selective, low nanomolar inhibitors of STK33’s kinase activity. The most potent and selective of these, BRD8899, failed to kill KRAS-dependent cells. While several explanations for this result exist, our data are most consistent with the view that inhibition of STK33’s kinase activity does not represent a promising anti-KRAS therapeutic strategy.