Drug Sensitivity Gene Promoter Methylation And Capecitabine In The Treatment Of Breast Cancer And Correlation Study

Objective.To assess methylation status of promoters of drug sensitivity-related genes and analyze the potential relationship between methylation status and sensitivity to chemotherapeutic drugs.Methods:The sensitivity of 4 breast cancer cell lines,including Bcap-37,T47D, MCF-7 and ZR-75-30,to 9 chemotherapeutic drugs(paclitaxel,docetaxel,vinorelbine,5-fluorouracil,gemcitabine,epirubicin,ironticon,irinotecan and cisplatin) was evaluated by MTT method and the methylation status of 27 gene promoters in the 4 breast cancer cell lines and 37 cases of clinical paraffin-embedded samples was assessed by methylation-specific polymerase chain reaction(MSP).Results:MTT results showed that significant difference only existed in sensitivity of the 4 breast cancer cell lines to 5-Fu.Bcap-37 and MCF-7 cell lines were more sensitive to 5-Fu than the other 2 cell lines.MSP test showed that promoter methylation status of the BMP3B(Bone morphogenetic protein 3B) and LOX(lysyl oxidase) genes was different between 5-Fu-resistant and 5-Fu-sensitive cell lines. BMP3B gene promoter was hypermethylated in 5-Fu-resistant cell lines,while LOX gene promoter was hypermethylated in 5-Fu-sensitive cell lines.Results from clinical samples were not available.Conclusion:The methylation status of BMP3B and LOX gene promoters may be related to the sensitivity of breast cancer cell lines to 5-Fu,and clinical samples are needed to verify the relationship.