Abstract: Objective To establish human colorectal cancer(CRC) organoids and to evaluate the efficacy of chemotherapy drugs. Methods Patient-derived CRC cells were cultured to form organoids. The CRC organoids and original tissues were stained with molecular markers of CRC immunohishtochemically. CRC organoids were used to test drug sensitivity and different concentrations of chemotherapy drugs 5-fluorouracil, oxaliplatin and irinotecan were given respectively; Organoid activity before and after drug treatment was measured by 3D cell viability assay. Results The patient-derived organoids(PDO) from 5 CRC tissues were successfully established. The expression of CK20, Ki67 and Villin proteins was similar in organoids and in original tumor. The organoids retained histologcial features similar to those of the original tumors. Different PDO showed differential sensitivity to different chemotherapy drugs. Conclusions CRC-PDO can dispaly their different sensitivities to different chemotherapy drugs, and could provide valuble reference for personalized treatment for CRC patients.

Key words: colorectal cancer organoids, drug sensitivity