Zhou et al. suggested using a higher dose of chemoradiotherapy to destroy colon tumor cells more effectively based on the chemoradioprotective effects of Rspo1/Slit2 protein in normal tissue [7] Our results thus indicate that treatment with Rspo1 may also enhance tumor cell radioresistance, thereby interfering with the therapeutic effect. The gene discussed is SLIT2; the disease is colonic neoplasm.