we found that compared with the PBS group, the distribution of F4/80+ macrophages of the tumour and lymph in the MCC group gradually increased; compared with MCC + NIR group, the macrophages of the tumour and lymph in the PfCC+NIR treatment group were also significantly increased, indicating that MCC and antimicrobial peptides could induce macrophages response in tumours (Fig. 7l, m). This evidence concerns the gene MCC and Merkel cell skin cancer.