We are following a drug discovery approach that starts with the selection of a cellular pathway that is involved in human disease, followed by the development and validation of a reporter assay for small molecule screening. Libraries of compounds are assayed and analogs of hit compounds are synthesized in order to improve their activity and to learn about their structure-activity relationship. The obtained small molecule probes are then used to validate the initial pathway as a therapeutic target and to further study its biological and physiological implications.