Autophagy defects impair MDSC lysosomal degradation, upregulate MHC-II molecule expression, thereby activating tumor-specific CD4+T cells and reducing tumor volume; conversely, in multiple myeloma (MM), MDSCs induce tumor cell autophagy via AMPK phosphorylation, upregulating MCL-1/BCL-2 expression to enhance MM cell survival (111). The gene discussed is CD4; the disease is neoplasm.