MMP9 and neoplasm: An alternative way of interpreting the increased lymphocyte migration in the TIMP-1 deficient astrocytes exposed to TNF-α, refers to the possible regulation of ICAM-1 by gelatinases at the surface of astrocytes; MMPs cleave membrane-bound ICAM-1 in astrocytes [53], and MMP-9 appears to be the key enzyme processing ICAM-1 in tumour cells [54].