CXCL13 and nonpapillary renal cell carcinoma: Studies carried out by Zheng et al. reported that the CXCR5-CXCL13 axis promotes the growth of colorectal cancer and clear cell renal cell carcinoma (ccRCC) via activating PI3K/Akt/mTOR signaling (Zhu et al., 2015; Zheng et al., 2018).