IL-1β Induces Fascin Expression and Increases Cancer Invasion

Tumor microenvironment plays an important role in tumor growth and metastasis. Cancer cells can promote their growth and malignancy by altering the surrounding stroma. Fascin is an actin-bundling protein that regulates the dynamics of the cytoskeletal structure and plays a significant role in cancer invasion and metastasis. In this study, we observed stromal factors controlling fascin expression in cancer cells and investigated underlying signal transduction pathways.

Fascin depletion was performed with lentiviral short-hairpin RNA (shRNA) against fascin mRNA and a stable cell line (Fascin^dep) was established. Fascin expression and invasion activity induced by IL-1β treatement were observed through Matrigel-Transwell invasion and 3D culture system. Intermediated signaling molecules involved in fascin expression induced by IL-1β were elucidated using western blotting.

Fascin was more highly expressed in human OSCC cells than normal cells. Cancer invasion activity was decreased by fascin depletion using lentiviral shRNA. However, fascin expression was increased by IL-1β treatement, leading to increased extracellular matrix (ECM) degradation and infiltration into 3-dimensional (3-D) collagen matrix. Specific inhibitors of extracellular signal-regulated kinases-1/2 [ERK1/2, (PD98059)], c-Jun N-terminal kinase [JNK, (SP600125)], nuclear factor kappa light chain enhancer of activted B cells [NF-κB, (parthenolide)], and cAMP response element binding protein [CREB, (CREB inhibitor)] suppressed IL-1β -induced fascin expression. IL-1β induced phosphorylation of ERK1/2, JNK, NF-κB and CREB while IL-1 receptor (IL-1R) antagonist abolished their activation.

IL-1β is a critical inducer of fascin expression. ERK1/2, JNK, NF-κB, and CREB signaling pathways are involved in IL-1β-induced fascin expression and these paracrine signaling pathways can induce cancer cell invasion.