Interleukin-18 enhances breast cancer cell migration via down-regulation of claudin-12 and induction of the p38 MAPK pathway.

Abstract

Interleukin-18 (IL-18) was recently reported to have a pro-tumor effect in various cancers. Increased IL-18 levels in the serum of cancer patients correlated with malignancy, and IL-18 acts a crucial factor for cell migration in gastric cancer and melanoma. Claudins, which are the most important tight junction proteins, are also linked with cancer progression and metastasis. However, the relationship between claudins and IL-18 is not well-understood. Here, we show that the migratory ability of MCF-7 cells was reduced when endogenous IL-18 expression was inhibited with IL-18 siRNA. Moreover, exogenous IL-18 enhanced breast cancer cell migration and suppressed the expression of the tight junction proteins claudin-1, claudin-3, claudin-4, and claudin-12 in MCF-7 cells. Knockdown of claudin-3, claudin-4, and claudin-12, but not claudin-1, increased breast cancer migration with maximal effects observed in claudin-12 siRNA-transfected cells. To investigate whether the mitogen-activated protein kinase (MAPK) signaling pathway is involved in IL-18-induced cell migration and claudin-12 expression, cells were pretreated with SB203580 (an inhibitor of p38 MAPK) or PD98059 (an inhibitor of ERK1/2) prior to the addition of IL-18. Although pretreatment of MCF-7 cells with SB203580 blocked both the enhanced cell migration and the decreased claudin-12 expression, PD98059 only blocked cell migration and did not affect claudin-12 expression. In addition, exogenous IL-18 induced rapid phosphorylation of p38 MAPK. These results suggest that IL-18 is an important factor inducing breast cancer cell migration through down-regulation of claudin-12 and activation of the p38 MAPK pathway.

• Authors: Yoolhee Yang, Soyoung Cheon, Min Kyung Jung, Seok Bean Song, Daejin Kim, Hee Jung Kim, Hyunjeong Park, Sa Ik Bang, Daeho Cho
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 459 Issue 3 Pg. 379-86 (Apr 10 2015) ISSN: 1090-2104 [Electronic] United States
• PMID: 25727011 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 Elsevier Inc. All rights reserved.

Chemical References

• CLDN1 protein, human
• CLDN12 protein, human
• CLDN3 protein, human
• CLDN4 protein, human
• Claudin-1
• Claudin-3
• Claudin-4
• Claudins
• Flavonoids
• Imidazoles
• Interleukin-18
• Protein Kinase Inhibitors
• Pyridines
• RNA, Small Interfering
• Recombinant Proteins
• SB 203580
• 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one

Topics

• Breast Neoplasms (genetics, pathology, physiopathology)
• Cell Line, Tumor
• Cell Movement (drug effects, genetics, physiology)
• Claudin-1 (antagonists & inhibitors, genetics, physiology)
• Claudin-3 (antagonists & inhibitors, genetics, physiology)
• Claudin-4 (antagonists & inhibitors, genetics, physiology)
• Claudins (antagonists & inhibitors, genetics, physiology)
• Down-Regulation (drug effects)
• Female
• Flavonoids (pharmacology)
• Gene Knockdown Techniques
• Humans
• Imidazoles (pharmacology)
• Interleukin-18 (antagonists & inhibitors, genetics, physiology)
• MAP Kinase Signaling System (drug effects)
• MCF-7 Cells
• Protein Kinase Inhibitors (pharmacology)
• Pyridines (pharmacology)
• RNA, Small Interfering (genetics)
• Recombinant Proteins (pharmacology)
• Tight Junctions (drug effects, physiology)