Chitinase-3-like Protein 1 (YKL-40) Expression in Squamous Cell Skin Cancer

BACKGROUND/AIM: YKL-40 plays a role in proliferation and differentiation of malignant cells. The aim of this study was to examine whether YKL-40 is expressed in cutaneous squamous cell carcinoma (SCC). MATERIALS AND METHODS: The study was based on histologically-confirmed biopsies of cutaneous SCCs obtained from 38 patients. The tissue expression of YKL-40 was assessed using an immunohisto-chemical method. The percentage of cells showing a positive reaction as well as the intensity of the IHC reaction was assessed using the immunoreactive score developed by Remmele and Stegner. RESULTS: All samples of cutaneous SCCs showed cytoplasmic expression of YKL-40. The intensity of YKL-40 expression varied between 1 and 8 points, according to the applied scale. In the majority of cancers about 10-80% of tumor cells were positive for YKL-40. The intensity of the reaction was low (20 samples, 52.6%) or medium (18 samples, 47.4%). CONCLUSION: YKL-40 is expressed in cutaneous SCC. Further research is needed to establish the value of YKL-40 for diagnosis and monitoring of SCC.