Expressions of IL-8 and CXCL5 in uterine endometrioid carcinomas which have frequent neutrophil infiltration and comparison to colorectal adenocarcinoma.

In endometrioid carcinomas (ECs) of the uterine corpus, neutrophil accumulation within the carcinoma cell clusters is a representative microscopic finding. Because this accumulation is active, some sort of transmitter ought to exist between the EC cells and neutrophils. Interleukin-8 (IL-8) and C-X-C motif chemokine ligand 5 (CXCL5) is a cytokine that attracts neutrophils in vivo. In this study, we investigated IL-8, CXCL5 and C-X-C motif chemokine receptor 2 (CXCR2) (their chemokine receptor) expressions in ECs by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR). There are few reports on the relationship between these chemokines and ECs. For comparison, we enrolled samples of colorectal adenocarcinoma (CRAC), it is another representative tumor with neutrophil infiltration. We analyzed 30 ECs and 30 CRACs. We confirmed IL-8 expression (H-score ≥50 points) in 40% of EC and 7% of CRAC samples; CXCL5 expression in 7% of EC and 10% of CRAC samples; CXCR2 expression in 83% of EC and 53% of CRAC samples by immunohistochemistry. We examined each mRNA (IL-8 and CXCL5) expression of 3 representative EC and 3 CRAC samples. Finding IL-8 expression might indicate that this cytokine is important for the process of neutrophil accumulation, particularly within ECs. The participation of CXCL5 regarding neutrophil accumulation within their carcinoma cell clusters might be restrictive compared to IL-8.