Korean J Lab Med.  2003 Dec;23(6):455-463.

Upregulation of Reactive Oxygen Species and Resistance to Fas-mediated Apoptosis in Cervical Cancer Cell Lines Transfected with the IL-18 Receptor

• Yoon DY
• Park JW
• Kim JW

Abstract

BACKGROUND
The fas (CD95/Apo-1)/Fas ligand (FasL) system is reported to be involved in the suppression and stimulation of immune responses, and the reactive oxygen species (ROS) play a key role in the mechanism for resisting Fas-induced apoptosis of tumor cells. In this work, we investigated the effect of endogenous interleukin (IL)-18 on the regulation of immune related factors such as Fas/Fas ligand and intercellular adhesion molecules (ICAM), and of the ROS level in IL-18 receptor (IL-18R) transfected C-33A cells. METHODS: The cervical cancer cell line C-33A was transfected with IL-18R (C-33A/IL-18R). For the detection of pro-inflammatory cytokines in C-33A/IL-18R, reverse-transcriptase (RT) polymerase chain reaction (PCR), in situ enzyme-linked immunosorbent assay (ELISA), Western blot, and Northern blot analyses were performed. The level of p53 was determined by Western blot. Intracellular ROS, ICAM-1, FasL, and apoptosis in C-33A/IL-18R were measured by flow cytometry. RESULTS: In situ ELISA and RT-PCR showed that, among pro-inflammatory cytokines, IL-18 was induced in C-33A/IL-18R whereas there appeared no induction of the IL-1alpha, IL-1beta, tumor necrosis factor (TNF)-alpha, and IL-6. IL-18R transfection showed a slight enhancement of the Fas via upregulation of intracellular ROS and IL-18 in C-33A cells whereas there was no effect on the expression of p53, ICAM-1 and FasL. However, treatment with the agonistic anti-Fas antibody showed that the enhanced surface Fas was not functional or was not enough to induce apoptosis and the C-33A/IL-18R cells escaped still resistant to Fas-mediated apoptosis. CONCLUSIONS: IL-18R transfection induced IL-18 expression and enhanced ROS and Fas expression in C-33A cells. These results show that C-33A/IL-18R cells escaped from immunuosurveillance by failure to express ICAM-1 adhesion molecules and Fas ligand, and are resistant to Fas-mediated apoptosis.

Keyword

IL-18; Fas/FasL; IL-18R

MeSH Terms

Apoptosis*
Blotting, Northern
Blotting, Western
Cell Adhesion Molecules
Cell Line*
Cytokines
Enzyme-Linked Immunosorbent Assay
Fas Ligand Protein
Flow Cytometry
Intercellular Adhesion Molecule-1
Interleukin-18
Interleukin-6
Interleukins
Polymerase Chain Reaction
Reactive Oxygen Species*
Receptors, Interleukin-18*
Transfection
Tumor Necrosis Factor-alpha
United Nations
Up-Regulation*
Uterine Cervical Neoplasms*
Cell Adhesion Molecules
Cytokines
Fas Ligand Protein
Intercellular Adhesion Molecule-1
Interleukin-18
Interleukin-6
Interleukins
Reactive Oxygen Species
Receptors, Interleukin-18
Tumor Necrosis Factor-alpha