MARVELD1 (MARVEL domain containing 1) is a nuclear protein located on chromosome 10.2 that functions as a tumor suppressor by inhibiting cell proliferation and migration across multiple cancer types. 1 MARVELD1 regulates cell adhesion and motility through pre-mRNA processing of integrin β1, affecting focal adhesion kinase signaling and actin organization. 2 The protein modulates nonsense-mediated mRNA decay efficiency via interaction with SMG1, a mechanism dysregulated in lung cancer. 3 MARVELD1 suppresses epithelial-mesenchymal transition by maintaining balanced integrin β1/β4 expression and proper cell surface ultrastructure. 4 Under cellular stress, MARVELD1 translocates to the cytoplasm and mitochondria where it interacts with catalase to enhance reactive oxygen species scavenging and reduce exorbitant ROS levels. 5 In hepatocellular carcinoma and neuro2a cells, MARVELD1 overexpression increases p53 and p16 expression, enhances chemosensitivity, and suppresses tumorigenesis through regulation of transcriptional coactivators and protein methylation pathways. 67 MARVELD1 expression is frequently silenced through promoter methylation and histone deacetylation across multiple tumor types including lung, breast, ovarian, and reproductive system cancers, making it a valuable diagnostic biomarker and therapeutic target. 13