title: Plasma miR-221 as a predictive biomarker for chemoresistance in breast cancer patients who previously received neoadjuvant chemotherapy.
abstract: BACKGROUND
  Neoadjuvant chemotherapy (NAC) is increasingly being used in breast cancer treatment. Research has revealed an elevated expression of miR-221 in adriamycinresistant MCF-7/ADR cells. This study aimed to explore the potential role of miR-221 as a biomarker for chemosensitivity in breast cancer patients who previously received NAC.
  
  
  METHODS
  The expression levels of circulating miR-221 in the plasma of 93 breast cancer patients who previously received NAC and in 32 healthy individuals were assessed. The correlations between miR-221 and clinicopathological features and chemosensitivity were also analysed.
  
  
  RESULTS
  The expression level of miR-221 was significantly associated with hormone receptor (HR) status (p = 0.008). Patients with higher plasma miR-221 levels tended to be HR-negative. Patients with different miR-221 levels had significant differences in the overall response rate (p = 0.044) but not in the pathologic complete response rate (p = 0.477).
  
  
  CONCLUSIONS
  Our results indicate that plasma miR-221 may be a predictive biomarker for sensitivity to NAC in breast cancer patients.
authors.affiliation: Department of Breast Surgery, Sun-Yat-Sen Memorial Hospital, Sun-Yat-Sen University, Guangzhou, Guangdong, China.
authors.forename: Ruihua
authors.initials: R
authors.lastname: Zhao
authors.forename: Jiannan
authors.initials: J
authors.lastname: Wu
authors.forename: Weijuan
authors.initials: W
authors.lastname: Jia
authors.forename: Chang
authors.initials: C
authors.lastname: Gong
authors.forename: Fengyan
authors.initials: F
authors.lastname: Yu
authors.forename: Zefang
authors.initials: Z
authors.lastname: Ren
authors.forename: Kai
authors.initials: K
authors.lastname: Chen
authors.forename: Jianrong
authors.initials: J
authors.lastname: He
authors.forename: Fengxi
authors.initials: F
authors.lastname: Su
mesh_terms: D018943:Anthracyclines / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000097:blood*; D001943:Breast Neoplasms / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy*; D001952:Bridged-Ring Compounds / Q000627:therapeutic use; D017024:Chemotherapy, Adjuvant / Q000706:statistics & numerical data; D002681:China / Q000453:epidemiology; D019008:Drug Resistance, Neoplasm; D005260:Female; D006801:Humans; D035683:MicroRNAs / Q000097:blood*; D020360:Neoadjuvant Therapy / Q000706:statistics & numerical data; D015995:Prevalence; D011379:Prognosis; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D043823:Taxoids / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D018943:Anthracyclines; D014408:Biomarkers, Tumor; D001952:Bridged-Ring Compounds; D035683:MicroRNAs; D043823:Taxoids; C525709:MIR221, human; C080625:taxane