Interleukin-32 expression in the pancreas.
Interleukin (IL)-32 is a recently described proinflammatory cytokine characterized by the induction of nuclear factor (NF)-kappaB activation. We studied IL-32 expression in human pancreatic tissue and pancreatic cancer cell lines. Tissue samples were obtained surgically. IL-32 expression was evaluated by standard immunohistochemical procedures. IL-32 mRNA expression was analyzed by Northern blotting and real time PCR analyses. IL-32 was weakly immunoexpressed by pancreatic duct cells. In the inflamed lesions of chronic pancreas, the ductal expression of IL-32 was markedly increased. A strong expression of IL-32alpha was detected in the pancreatic cancer cells. In pancreatic cancer cell lines (PANC-1, MIA PaCa-2, and BxPC-3 cells), the expression of IL-32 mRNA and protein was enhanced by IL-1beta, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha. An inhibitor of phosphatidylinositol 3-kinase (LY294002) significantly suppressed the IL-1beta-, IFN-gamma- and TNF-alpha-induced IL-32 mRNA expression. The blockade of NF-kappaB and activated protein-1 activation markedly suppressed the IL-1beta-, IFN-gamma-, and/or TNF-alpha-induced IL-32 mRNA expression. Furthermore, IL-32-specific small interfering RNA significantly decreased the uptake of [3H]thymidine and increased the annexin V-positive population (apoptotic cells) in PANC-1 cells. IL-32 knockdown also suppressed the mRNA expression of antiapoptotic proteins (Bcl-2, Bcl-xL, and Mcl-1). Pancreatic duct cells are the local source of IL-32, and IL-32 may play an important role in inflammatory responses and pancreatic cancer growth.
Nishida
Atsushi
A
Department of Medicine, Shiga University of Medical Science, Seta-Tukinowa, Otsu 520-2192, Japan.
Andoh
Akira
A
Inatomi
Osamu
O
Fujiyama
Yoshihide
Y
D017209:Apoptosis; D015152:Blotting, Northern; D015153:Blotting, Western; D021441:Carcinoma, Pancreatic Ductal / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D049109:Cell Proliferation; D002478:Cells, Cultured; D024202:Electrophoretic Mobility Shift Assay; D004797:Enzyme-Linked Immunosorbent Assay; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007124:Immunoenzyme Techniques; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D053583:Interleukin-1beta / Q000235:genetics / Q000378:metabolism; D007378:Interleukins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D010179:Pancreas / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D018808:Transcription Factor AP-1 / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
D007371:Interferon-gamma; D053583:Interleukin-1beta; D007378:Interleukins; D016328:NF-kappa B; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha; C496971:IL32 protein, human