It was found that the organoid cultured in vitro could largely maintain the DNA methylation patterns of gene promoter regions as those of in vivo tumor tissues, including the genes BCL2L1, IMPDH2, and TGFBI, which have been reported to be associated with CRC progression (Sillars-Hardebol et al., 2012; Duan et al., 2018; Chiavarina et al., 2021) (Fig. S1D). The gene discussed is BCL2L1; the disease is colorectal carcinoma.