We also quantify a 2SC peptide from the chloride intracellular channel protein 1 (CLIC1) protein, a chloride ion channel that regulates cellular oxidation levels and has been shown to be associated with regulating cell cycle29, also significantly elevated at the protein level in HLRCC versus NS ULMs (Supplemental Table 9). Here, CLIC1 is linked to hereditary leiomyomatosis and renal cell cancer.