Efflux pump; part of the gene cluster that mediates the biosynthesis of asperfuranone, a probable antitumor agent (PubMed:19199437). Expression is regulated by the asperfuranone cluster transcription factor afoA (PubMed:19199437). Strongly diminishes production of asperfuranone (PubMed:19199437). Asperfuranone provides anti-proliferative activity in human non-small cell lung cancer cells (PubMed:20148857). Belongs to the major facilitator superfamily.