ZAP70 and B-cell chronic lymphocytic leukemia: This downregulation may contribute to the aggressive phenotype observed in ZAP-70+ cases [80]; miR-29a, another tumor suppressor, is also reduced in ZAP-70+ CLL, allowing overexpression of oncogenic targets like TCL1 and anti-apoptotic proteins such as MCL1, thereby promoting survival and proliferation [81].