Aberrant expression of a disintegrin and metalloproteinase 17/tumor necrosis factor-alpha converting enzyme increases the malignant potential in human pancreatic ductal adenocarcinoma.
A disintegrin and metalloproteinase (ADAM) molecules are known for their unique potential to combine adhesion, proteolysis, and signaling. To understand the role of ADAM17/tumor necrosis factor-alpha (TNF-alpha) converting enzyme (TACE) in pancreatic ductal adenocarcinoma (PDAC), we investigated its expression, function, and in vitro regulation. ADAM17/TACE mRNA was expressed in 3 of 10 normal pancreatic tissues, 6 of 8 samples from patients with chronic pancreatitis, 10 of 10 PDAC tissues, and 9 of 9 pancreatic cancer cell lines, but it was absent in primary duct epithelial cells. Immunohistochemical staining revealed positive cancer cells in 8 of 10 PDACs but no staining of ducts in normal pancreas. ADAM17/TACE was found in 0 of 16 pancreatic intraepithelial neoplasia (PanIN)-1A lesions, 1 of 30 PanIN-1B lesions, 2 of 13 PanIN-2 lesions but, in 13 of 15 PanIN-3 lesions, associated with PDAC. Western blot, flow cytometry, and confocal microscopy analyses showed the aberrant expression of ADAM17/TACE protein in pancreatic cancer cell lines. The proteolytic activity of ADAM17/TACE, assessed by the release of TNF-alpha, was inhibited by TNF-alpha protease inhibitor. ADAM17/TACE gene silencing using small interfering RNA technique in vitro reduced invasion behavior dramatically, whereas proliferation was unaffected. Furthermore, ADAM17/TACE mRNA expression was down-regulated in pancreatic cancer cells arrested in G2-M phase as well as in a time-dependent manner after TNF-alpha and interleukin-6 incubation. In conclusion, our findings provide evidence of aberrant expression of the proteolytically active ADAM17/TACE in advanced precursor lesions (PanIN-3) and PDAC while identifying its critical involvement in the invasion process.
Ringel
Jörg
J
Department of Medicine II, Mannheim Medical Faculty, University of Heidelberg, Heidelberg, Germany.
Jesnowski
Ralf
R
Moniaux
Nicolas
N
Lüttges
Jutta
J
Ringel
Jens
J
Choudhury
Amit
A
Batra
Surinder K
SK
Klöppel
Günter
G
Löhr
Matthias
M
D051722:ADAM Proteins / Q000096:biosynthesis* / Q000235:genetics; D000072198:ADAM17 Protein; D021441:Carcinoma, Pancreatic Ductal / Q000201:enzymology* / Q000235:genetics / Q000473:pathology*; D002453:Cell Cycle / Q000235:genetics; D048708:Cell Growth Processes / Q000235:genetics; D045744:Cell Line, Tumor; D018450:Disease Progression; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D006801:Humans; D007150:Immunohistochemistry; D009361:Neoplasm Invasiveness; D010190:Pancreatic Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000473:pathology*; D050500:Pancreatitis, Chronic / Q000201:enzymology / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics
D012333:RNA, Messenger; D051722:ADAM Proteins; D000072198:ADAM17 Protein; C000606462:ADAM17 protein, human