ATG12 and nonpapillary renal cell carcinoma: The presence of the ATG12S isoform in SETD2-deficient ccRCC cells is associated with the presence of an additional ATG12-containing complex, and of free ATG12, which appears based on its molecular weight to be ATG12L, suggesting that ATG12S may compete with ATG12L and thereby act as repressor for the ATG12-conjugation system.