title: Expression of interleukin-23 and its receptors in human squamous cell carcinoma of the oral cavity.
abstract: Interleukin (IL)-23 is a heterodimeric cytokine comprising IL-12p40 and the recently cloned IL-23-specific p19 subunit. Like IL-12, IL-23 is expressed predominantly by activated dendritic cells and phagocytic cells. Both cytokines induce interferon-γ secretion by T cells, and antagonistically regulate local inflammatory responses in the tumor microenvironment as well as the infiltration of intra-epithelial lymphocytes. Although the expression of IL-23 in various organs has been reported, it is unclear whether IL-23 is expressed in oral cancer. The expression of IL-23 and its receptors was examined in human oral squamous cell carcinoma (HOSCC) cell lines and tissue. IL-23 and its receptor mRNAs and proteins were spontaneously expressed, and IL-23 was increased by TNF-α stimulation in the oral cancer cells. A cell proliferation assay confirmed that IL-23 promotes cell proliferation in oral cancer. The localization of IL-23 protein in HOSCC tissue was examined using immunohistochemistry. A positive reaction for anti-IL-23 antibody was weakly observed in the cytoplasm of inflammatory infiltrating cells and cancer cells in HOSCC tissue. Meanwhile, nuclear factor-κB immunoreactivity was strongly positive in HOSCC tissue, which is particularly consistent with the observation of IL-23-positive cells in SCC tissue. These data suggest that IL-23 plays a significant role in the growth and proliferation of oral cancer.
authors.affiliation: Second Division of Oral and Maxillofacial Surgery, Department of Diagnostic and Therapeutic Sciences, Meikai University School of Dentistry, Saitama 350-0283, Japan. fukudam@dent.meikai.ac.jp.
authors.forename: Masakatsu
authors.initials: M
authors.lastname: Fukuda
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ehara
authors.forename: Seiji
authors.initials: S
authors.lastname: Suzuki
authors.forename: Hideaki
authors.initials: H
authors.lastname: Sakashita