Considering that the infiltration of immune cells within tumors is linked to immunotherapy outcomes, we examined the relationship between METTL5 expression and key immune cell markers in tumor samples from both datasets, METTL5 expression shows no significant association with the expressions of key immune cell markers for T cell, cytotoxic T cell (CTL), B cell and NK cells at tumor sites (Figure S4C, Supporting Information). This evidence concerns the gene METTL5 and neoplasm.