Role for Furin in Tumor Necrosis Factor Alpha-Induced Activation of the Matrix Metalloproteinase/Sphingolipid Mitogenic Pathway

Abstract

Neutral sphingomyelinase (nSMase), the initial enzyme of the sphingolipid signaling pathway, is thought to play a key role in cellular responses to tumor necrosis factor alpha (TNF-␣), such as inflammation, proliferation, and apoptosis. The mechanism of TNF-␣-induced nSMase activation is only partly understood. Using biochemical, molecular, and pharmacological approaches, we found that nSMase activation triggered by TNF-␣ is required for TNF-␣-induced proliferation and in turn requires a proteolytic cascade involving furin, membrane type 1 matrix metalloproteinase (MT1-MMP), and MMP2, and leading finally to extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and DNA synthesis, in smooth muscle cells (SMC) and fibroblasts. Pharmacological and molecular inhibitors of MMPs (batimastat), furin (␣1-PDX inhibitor-transfected SMC), MT1-MMP (SMC overexpressing a catalytically inactive MT1-MMP), MMP2 (fibroblasts from MMP2؊/؊ mice), and small interfering RNA (siRNA) strategies (siRNAs targeting furin, MT1-MMP, MMP2, and nSMase) resulted in near-complete inhibition of the activation of nSMase, sphingosine kinase-1, and ERK1/2 and of subsequent DNA synthesis. Exogenous MT1-MMP activated nSMase and SMC proliferation in normal but not in MMP2 ؊/؊ fibroblasts, whereas exogenous MMP2 was active on both normal and MMP2؊/؊ fibroblasts. Altogether these findings highlight a pivotal role for furin, MT1-MMP, and MMP2 in TNF-␣-induced sphingolipid signaling, and they identify this system as a possible target to inhibit SMC proliferation in vascular diseases.

Uterine cervical carcinoma: Role of matrix metalloproteinases (Review)

“…Many studies have also observed that MMPs, and in particular MMP-2 and MMP-9, are expressed in stromal cells and inflammatory cells around tumors (72). These findings suggest the importance of these proteases in the pathogenesis of cancer.…”

Membrane type 1 matrix metalloproteinase (MT1-MMP) and the regulators of its activity as invasive factors in squamous cell cervical carcinomas

“…L-аргинил-треонил-лизил-L-аргинина (Pyr-ArgThe-Lys-Arg-MCA) [20]. Опытная проба объёмом 500 мкл содержит 5-100 мкл образца (5-10 мкг белка), Pyr-Arg-The-Lys-Arg-MCA (в конечной концентрации 4´10 -5 М).…”

“…ТИМПы обладают "цитокино-подобной" активностью и могут принимать участие в регуляции таких процессов как апоптоз и клеточный рост [4,[7][8][9]. Активация про-МТ1-ММП осуществляется внутриклеточно в аппарате Гольджи с помощью сериновой протеиназы -фурина [10].…”

Identification of Novel Anionic Phospholipid Binding Domains in Neutral Sphingomyelinase 2 with Selective Binding Preference

“…Prior to the cloning of nSMase2, it was first identified as a confluent cell-associated gene in rat 3Y1 cells (14) and was subsequently implicated in confluence-induced G 0 /G 1 cell cycle arrest in MCF-7 breast cancer cells (15). Many studies have reported activation of nSMase2 by tumor necrosis factor in a variety of cell types including smooth muscle cells, HUVECs and A549 cells, although regulation of nSMase2 appears to be cell type dependent with protein kinase C-delta and p38 MAPK involved in A549 cells (16,17), and matrix metalloproteinases, furin and integrins involved in smooth muscle cells (18). In addition, nSMase2 was implicated in aging-associated inflammation, particularly in the response to interleukin-1␤ (19).…”