Objective      To establish a crizotinib-resistant cell line NCI-H3122 of non-small cell lung cancer (NSCLC)

identify its drug resistance

and determine the drug-resistant related miRNAs preliminarily.       Methods      The human NCI-H3122CR cells were established by continuous stepwise selection in increasing concentration of crizotinib. The resistance of NIC-H3122CR was determined by cell sensitivity

growth curves

cell apoptosis and cell cycle distribution. Furthermore

the differential expression of microRNAs related to drug resistance was determined by next-generation sequencing and RT-PCR.       Results      The crizotinib-resistant lung cancer cell line H3122CR was successfully established

and its drug resistance index was 9.86. Flow cytometry showed that the apoptotic rate was lower in the H3122CR cells than the H3122 cells

in a dose-dependent manner. Moreover

the results of next-generation sequencing and RT-PCR revealed that the expression levels of miR-30a-5p

miR-374c-5p and miR-125b-5p were up-regulated

while those of miR-31-5p

miR-10a-5p and miR-200c-3p down-regulated.       Conclusion      Our established H3122CR cell line presents certain crizotinib resistant characteristics

and the expression levels of some miRNAs are changed significantly in response to the resistance.