Identification of the interleukin-8 (CXCL-8) pathway in feline oral squamous cell carcinoma — A pilot study

• Published in: Canadian journal of veterinary research Vol. 86; no. 1; pp. 13 - 19
• Main Authors: Ackerman, Leah H., de Mello Souza, Carlos H., Cortés-Hinojosa, Galaxia, Salute, Marc E., Stephen, Alexa A., Anthony, Elizabeth, Shiomitsu, Keijiro, Milner, Rowan J.
• Format: Journal Article
• Language: English
• Published: Canada Canadian Veterinary Medical Association 01.01.2022
• Subjects: Animals; Carcinoma, Squamous Cell - metabolism; Carcinoma, Squamous Cell - veterinary; Cat Diseases - metabolism; Cats; Cell Line, Tumor; Interleukin-8 - genetics; Interleukin-8 - metabolism; Mouth Neoplasms - metabolism; Mouth Neoplasms - veterinary; Pilot Projects; RNA, Messenger - isolation & purification; Signal Transduction; Tumor Microenvironment
• ISSN: 0830-9000; 1928-9022

The purpose of this pilot study was to detect the presence of interleukin-8 (IL-8) and the potential downstream effects of IL-8 receptor activation in 2 previously characterized feline oral squamous cell carcinoma cell lines (SCCF1 and SCCF2). Interleukin-8 messenger RNA (mRNA) was initially detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). A previously validated and commercially available enzyme-linked immunosorbent assay (ELISA) test was used to measure IL-8 production in the supernatant of the 2 cell lines. Western blot was used to detect phosphorylation of proteins (AKT, ERK1/2, JAK2, STAT3, and Src), known to be downstream of interleukin-8 receptor activation. The IL-8 receptor-specific antagonists, Reparixin and SCH527123, were used to identify effects on phosphorylation of these proteins. Interleukin-8 mRNA and protein were detected in both SCCF1 and SCCF2 by RT-PCR and ELISA, respectively. Phosphorylation of ERK1/2, STAT3, and Src was detected in both cell lines. Inhibition of the IL-8 receptor led to a decrease in phosphorylation of Src, but not ERK1/2 or STAT3. In conclusion, feline squamous cell carcinoma cell lines can produce IL-8. Phosphorylation of Src seems, at least in part, a consequence of IL-8 receptor activation. The phosphorylation of ERK1/2 and STAT3, although present, seems independent of IL-8 receptor activation. Due to its potential effects on the tumor microenvironment, in addition to its autocrine effects on Src phosphorylation, the inhibition of the IL-8 receptor may become a beneficial therapeutic tool. Evaluation of the presence of both IL-8 and Src in many cases should elucidate their importance.