SEEKING DRUGS THAT INCREASE KIT LIGAND GENE EXPRESSION

THE LIGAND FOR THE C-KIT RECEPTOR FUNCTIONS AS A POTENT GROWTH FACTOR AND DIFFERENTIATION INDUCER FOR VERY EARLY HEMOTOPOIETIC STEM CELLS. THE KIT LIGAND PROTEIN IS CURRENTLY BEING EVALUATED BY SEVERAL LABS FOR THERAPEUTIC UTLITY IN COMBINATION WITH OTHER HEMATOPOIETIC GROWTH FACTORS FOR THE TREATMENT OF ANEMIA AND LEUKOPENIA. WE WILL DEVELOP A SYSTEM TO IDENTIFY SMALL MOLECULAR WEIGHT COMPOUNDS WHICH FUNCTION TO INCREASE THE EXPRESSION OF THE PATIENT'S OWN KIT LIGAND (KL) GENE. SUCH COMPOUNDS COULD POTENTIALLY BE USED AS PHARMACEUTICAL TO INCREASE THE EFFECTIVENESS OF, OR REDUCE THE REQUIRED DOSAGE OF, THERAPEUTICALLY ADMINISTERED HEMATOPOIETIC GROWTH FACTORS LIKE ERYTHROPOIETIC GROWTH FACTORS FOR THE TREATMENT OF ANEMIA AND LEUKOPENIA. WE WILL DEVELOP A SYSTEM TO IDENTIFY SMALL MOLECULAR WEIGHT COMPOUNDS WHICH FUNCTION TO INCREASE THE EXPRESSION OF THE PATIENT'S OWN KIT LIGAND (KL) GENE. SUCH COMPOUNDS COULD POTENTIALLY BE USED AS PHARMACEUTICAL TO INCREASE THE EFFECTIVENESS OF, OR REDUCE THE REQUIRED DOSAGE OF, THERAPEUTICALLY ADMINISTERED HEMATOPOIETIC GROWTH FACTORS LIKE ERYTHROPOIETIN OR G-CSF. OUR TECHNICAL APPROACH IS TO: 1) FUSE THE KL TRANSCRIPTIONAL REGULATORY ELEMENTS TO THE FIREFLY LUCIFERASE GENE, 2) USE THIS REPORTER CONSTRUCT TO CREATE A STABLY TRANSFECTED KL-LUCIFERASE REPORTER CELL LINE, AND 3) USE THIS CELL LINE (AND APPROPRIATE CONTROLS) TO ANALYZE NATURAL PRODUCTS EXTRACTS AND CHEMICAL FILES SEEKING COMPOUNDS WHICH SPECIFICALLY UP-REGULATE KL TRANSCRIPTION. THE CELL LINE CONSTRUCTION WILL BE COMPLETED, TESTED AND SCREENING INITIATED DURING PHASE II. THE PROJECT WILL BE COMMERCIALIZED BY ESTABLISHING A COLLABORATION WITH A MAJOR PHARMACEUTICAL COMPANY TO CONTINUE THE PROCESS OF DRUG DEVELOPMENT.