High expression of CD34 and α6-integrin contributes to the cancer-initiating cell behaviour in ultraviolet-induced mouse skin squamous cell carcinoma

Squamous cell carcinoma caused by ultraviolet light exposure represents over 40% of all malignant diseases. It is one of the most commonly found human tumours. Tumour mass within squamous cell carcinoma consists of various cell types, including cancer-initiating cells that are responsible for tumour progression, metastasis and chemoresistance and implicated in clinical relapse. In the present study, we aimed to characterise whether the cell population with high CD34 and α6-integrin expression behave as cancer-initiating cells within ultraviolet-induced squamous cell carcinoma in mouse skin. CD34highα6-integrinhigh compared to CD34lowα6-integrinhigh cells isolated from ultraviolet-induced squamous cell carcinoma could propagate effectively by displaying greater tumour initiating and self-renewal abilities. Our study suggests that CD34highα6-integrinhigh cells act as initiators upon ultraviolet-induced skin squamous cell carcinoma.