CCL5 and renal cell carcinoma: Previous work by Jinhua Wang et al. has demonstrated in vitro that silencing APOC1 expression reverses the M2 polarization of tumor-associated macrophages (TAMs) co-cultured with renal cell carcinoma cells, while macrophages overexpressing APOC1 promote the metastasis of renal cell carcinoma through CCL5 (Ren et al., 2022).