The inflammatory markers CCL2 and CXCL1 are also related to tumorigenesis and metastasis.(30, 31) Because inflammation and cancer are tightly correlated,(47) the significant upregulation of CCL2 and CXCL1 expression in the Ca‐45‐injected mice at 26–32 weeks after IR compared with 2–8 weeks after IR might have partially contributed to tumorigenesis under the chronic LDR‐IR conditions. The gene discussed is CCL2; the disease is cancer.