title: Influence of MDR1 methylation on the curative effect of interventional embolism chemotherapy for cervical cancer.
abstract: BACKGROUND
  Multi-drug resistance (MDR) is the main cause of tumor failure to chemotherapy. This study aims to explore the influence of MDR1 methylation on curative effect of interventional embolism chemotherapy for cervical cancer.
  
  
  METHODS
  Sixty-seven patients with cervical cancer receiving embolism chemotherapy were selected, and 45 normal cervical tissues were included as a control. Immunohistochemistry was used to detect the level of P-glycoprotein (P-gp) in cervical cancer, and to make an analysis compared with normal tissues. The methylation status of the MDR1 gene promoter region 16 CpG units was analyzed by using kilobase-specific cracking and matrix-assisted laser desorption ionization time of flight mass spectrometry.
  
  
  RESULTS
  The results indicated that the positive expression rates of P-gp were 0% (0/45) in normal cervical tissue, and 61.19% (41/67) and 77.61% (52/67) before and after interventional embolism chemotherapy in cervical cancer tissues, respectively. There were significant differences compared with normal cervical tissues (χ (2)=4.2523, 0.0392). The positive expression rate of P-gp before chemotherapy was negatively correlated with efficacy of chemotherapy (r=-0.340, P=0.005). Methylation rate of 13 CpG units in normal tissues was significantly greater than cervical tissues (P<0.05). In cervical cancer tissue, methylation rate of six CpG units before interventional embolism chemotherapy was higher than after chemotherapy, but that of one CpG unit was lower than after chemotherapy (P<0.05). The methylation rate of one CpG unit with effective chemotherapy before chemotherapy was significantly higher than ineffective chemotherapy (P<0.05), and the other CpG units were similar (P>0.05).
  
  
  CONCLUSIONS
  P-gp expression level coded by MDR1, methylation status of partial MDR1 gene promoter regions CpG island, is closely related to the efficacy of interventional embolism chemotherapy for cervical cancer before the operation.
authors.affiliation: Department of Interventional Radiology, The Affiliated Baiyun Hospital of Guizhou Medical University, Guizhou Medical University, Guiyang, People's Republic of China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Interventional Radiology, Cancer Hospital of Guizhou Medical University, Guiyang, People's Republic of China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Interventional Radiology, The Affiliated Baiyun Hospital of Guizhou Medical University, Guizhou Medical University, Guiyang, People's Republic of China.
authors.forename: Yaping
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Department of Interventional Radiology, The Affiliated Baiyun Hospital of Guizhou Medical University, Guizhou Medical University, Guiyang, People's Republic of China.
authors.forename: Weixin
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Interventional Radiology, The Affiliated Baiyun Hospital of Guizhou Medical University, Guizhou Medical University, Guiyang, People's Republic of China.
authors.forename: Jipu
authors.initials: J
authors.lastname: Long
authors.affiliation: Department of Interventional Radiology, The Affiliated Baiyun Hospital of Guizhou Medical University, Guizhou Medical University, Guiyang, People's Republic of China.
authors.forename: Shi
authors.initials: S
authors.lastname: Zhou
keywords: MDR1 gene; cervical cancer; immunohistochemistry; interventional embolism chemotherapy; methylation