Abstract:Objective: To study the infiltration patterns of immune cells in cutaneous melanoma and to explore the relationship between immune cells infiltration and clinical prognosis. Methods: Transcripts and related clinical data of cutaneous melanoma were downloaded from the cancer genome atlas (TCGA) database. The proportion of 22 kinds of immune cells were calculated by deconvolution method with Cibersort software. The correlation between immune cells proportion and gender was calculated by R programming language, and K-M survival analysis with log-rank method was used to determine the correlation between each kind of immune cells and overall survival (OS). Results: A total of 472 gene transcripts were obtained from the TCGA database, including 470 cases of cutaneous melanoma and 2 cases of normal tissues. Each sample detected 60, 483 genetic loci and extracted 19, 658 mRNAs. After data correction, the proportion of 22 kinds of immune cells was obtained by deconvolution method with Cibersort software. Totally 219 cases of cutaneous melanoma and 1 case of normal skin tissue were obtained by screening samples with the criteria P<0.05. M0 macrophages, CD8+T cells, and M2 macrophages were the types of immune cells with higher levels of infiltration in melanoma tissues. The strongly correlated immune cells included CD8+T cells and M0 macrophages (-0.62), and inactivated CD4+T cells and CD8+T cells (-0.53).K-M survival analysis showed that patients with the higher proportion of inactivated mast cells (P=0.015) and inactivated NK cells (P=0.025) had worse prognosis, and patients with the higher proportion of γδT cells (P=0.043) had better prognosis. The proportion of inactive mast cells in female with melanoma was less than that in male (P=0.028). Conclusion: There are differences in the composition of infiltrated immune cells in cutaneous melanoma. These cells are likely to be important determinants of prognosis, which helps us develop effective immunotherapy.
