We further identified 9 proteins that were decreased in HLRCC ULMs including several predicted to be localized to the extracellular matrix, such as fibulin 2 (FBLN2, − 1.35) and laminin subunit alpha 2 (LAMA2, − 1.11) as well as the transcription factor PBX homeobox 1 (PBX1, − 0.66). The gene discussed is PBX1; the disease is hereditary leiomyomatosis and renal cell cancer.