MAPK8 and neoplasm: However, scrib- + NACT + bskDN clones also exhibited elevated Hth levels indicating that the upregulation was not JNK-dependent (S3D Fig); and expressing NACT in scrib-hth- double mutant clones still elicited the formation of large invasive tumors throughout an extended larval stage, indicating that Hth was not absolutely required for tumor overgrowth (S3F Fig).