Protease activity profiling of ovarian clear cell carcinoma

ABSTRACT: Ovarian clear cell carcinoma (OCCC) is an understudied poor prognosis subtype of ovarian cancer lacking in effective molecularly targeted therapies; efforts to define drivers of OCCC malignancy may lead to new therapeutic targets and approaches. Among potential targets are secreted proteases, enzymes which in many cancers serve as key drivers of malignant progression. To identify proteases responsible for the proteolytic landscape of the tumor microenvironment requires methods that directly report on enzyme activity, as transcript or protein abundance alone are poor indicators of protease activity. Here we developed an activity-based probe featuring an arginine diphenylphosphonate warhead to detect active serine proteases of trypsin-like specificity. A biotin handle was incorporated to facilitate affinity purification of labeled proteases. Using this probe, we employed activity-based protein profiling to identify active trypsin-like serine proteases within the complex proteome secreted by OCCC cell lines. We identified multiple active serine proteases in OCCC cell lines, including two proteases in common, tissue plasminogen activator (tPA) and urokinase-type plasminogen activator (uPA). Further interrogation of these proteases showed that both were involved in cancer cell invasion and proliferation of OCCC cells. The detection of tPA and uPA as catalytically active proteases and significant drivers of the malignant phenotype may point to these enzymes as targets for new therapeutic strategies in OCCC. Our activity-based probe and profiling methodology also offer a valuable tool for detection of active trypsin-like serine proteases in models of other cancers and other diseases.

INSTRUMENT(S): LTQ Orbitrap Elite

ORGANISM(S): Homo Sapiens (ncbitaxon:9606)

SUBMITTER: Evette Radisky  

PROVIDER: MSV000087385 | MassIVE | Fri May 07 07:30:00 BST 2021

SECONDARY ACCESSION(S): PXD025880

REPOSITORIES: MassIVE