Journal Article

IL-24 Inhibits Lung Cancer Cell Migration and Invasion by Disrupting The SDF-1/CXCR4 Signaling Axis

Hubin, Timothy J., Shanker, Manish, Jin, Jiankang, Zhao, Yan D., Bates, Jonathan, Lauderdale, Jason, Wang, Qi, Ramesh, Rajagopal, Archibald, Stephen J., Panneerselvam, Janani

2015

Overview

The stromal cell derived factor (SDF)-1/chemokine receptor (CXCR)-4 signaling pathway plays a key role in lung cancer metastasis and is molecular target for therapy. In the present study we investigated whether interleukin (IL)-24 can inhibit the SDF-1/CXCR4 axis and suppress lung cancer cell migration and invasion in vitro. Further, the efficacy of IL-24 in combination with CXCR4 antagonists was investigated. Human H1299, A549, H460 and HCC827 lung cancer cell lines were used in the present study. The H1299 lung cancer cell line was stably transfected with doxycycline-inducible plasmid expression vector carrying the human IL-24 cDNA and used in the present study to determine the inhibitory effects of IL-24 on SDF-1/CXCR4 axis. H1299 and A549 cell lines were used in transient transfection studies. The inhibitory effects of IL-24 on SDF1/CXCR4 and its downstream targets were analyzed by quantitative RT-PCR, western blot, luciferase reporter assay, flow cytometry and immunocytochemistry. Functional studies included cell migration and invasion assays. Endogenous CXCR4 protein expression levels varied among the four human lung cancer cell lines. Doxycycline-induced IL-24 expression in the H1299-IL24 cell line resulted in reduced CXCR4 mRNA and protein expression. IL-24 post-transcriptionally regulated CXCR4 mRNA expression by decreasing the half-life of CXCR4 mRNA (>40%). Functional studies showed IL-24 inhibited tumor cell migration and invasion concomitant with reduction in CXCR4 and its downstream targets (pAKTS473, pmTORS2448, pPRAS40T246 and HIF-1α). Additionally, IL-24 inhibited tumor cell migration both in the presence and absence of the CXCR4 agonist, SDF-1. Finally, IL-24 when combined with CXCR4 inhibitors (AMD3100, SJA5) or with CXCR4 siRNA demonstrated enhanced inhibitory activity on tumor cell migration. IL-24 disrupts the SDF-1/CXCR4 signaling pathway and inhibits lung tumor cell migration and invasion. Additionally, IL-24, when combined with CXCR4 inhibitors exhibited enhanced anti-metastatic activity and is an attractive therapeutic strategy for lung metastasis.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Biotechnology / Cancer / Cancer metastasis / Carcinoma, Non-Small-Cell Lung - genetics / Carcinoma, Non-Small-Cell Lung - metabolism / Carcinoma, Non-Small-Cell Lung - pathology / Cell adhesion & migration / Cell Line, Tumor / Cell migration / Cell Movement - drug effects / Cell Movement - genetics / Chemokine CXCL12 - metabolism / Chemokines / CXCR4 protein / Cytokines / Cytometry / Downstream / Doxycycline / Drug Synergism / Flow cytometry / Gene Expression / Gene Expression Regulation, Neoplastic / Gene therapy / Genetic vectors / Health aspects / Health sciences / Heart surgery / Heterocyclic Compounds - pharmacology / Humans / Immunocytochemistry / Inhibitors / Interleukin 24 / Interleukins / Interleukins - genetics / Interleukins - pharmacology / Leukemia / Ligands / Luciferase / Lung cancer / Lung diseases / Lung Neoplasms - genetics / Lung Neoplasms - metabolism / Lung Neoplasms - pathology / Melanoma / Metastases / Metastasis / Pathology / Polymerase chain reaction / Post-transcription / Protein expression / Proteins / Proto-Oncogene Proteins c-akt - genetics / Proto-Oncogene Proteins c-akt - metabolism / Receptors, CXCR4 - antagonists & inhibitors / Receptors, CXCR4 - genetics / Receptors, CXCR4 - metabolism / RNA / RNA, Small Interfering / SDF-1 protein / Signal transduction / Signal Transduction - drug effects / Signaling / siRNA / Studies / TOR Serine-Threonine Kinases - metabolism / Transfection / Tumor cell lines / Tumors