title: [Relationship between the response of breast cancer to neoadjuvant chemotherapy and PI3K/mTOR pathway].
abstract: OBJECTIVE
  To explore the relationship between the status of PI3K/mTOR pathway and the therapeutic efficacies of neoadjuvant chemotherapy for breast cancer.
  
  
  METHODS
  A total of 105 patients receiving 4-6 cycles of taxane-based neoadjuvant chemotherapy at our centre between January 2009 and November 2010 were recruited into this retrospective study. The expressions of PTEN, p-AKT (Ser473) and p-mTOR (Ser2448) were detected by immunohistochemistry before neoadjuvant chemotherapy. We employed pathology to evaluate the therapeutic efficacies and considered complete response (G4) & pathologic complete response (PCR) as efficacious. Fourfold table Chi-square test and binary Logistic regression were used to analyze the relationship between the above features and therapeutic efficacies.
  
  
  RESULTS
  The overall efficacy rate of neoadjuvant chemotherapy was 58.1% (61/105) and the PCR rate 27.6% (29/105). The positive expression rates of PTEN, p-AKT and p-mTOR were 52.4% (57/105), 68.6% (72/105) and 43.8% (46/105) respectively. Fourfold table Chi-square test showed the difference between p-mTOR and therapeutic efficacy was significant statistically (P = 0.003) and also the difference between p-mTOR and PCR (P = 0.001). Binary Logistic regression showed the difference between p-mTOR and therapeutic efficiency was significant statistically, and also the difference between p-mTOR and PCR (both P < 0.01). The differential expressions of p-mTOR and p-AKT were statistically significant (P = 0.000) and so were those of p-AKT and PR (P = 0.035).
  
  
  CONCLUSIONS
  The status of p-mTOR has predictive values for taxane-based neoadjuvant chemotherapy. The patients with a low level of p-mTOR are more responsive to thermotherapy while those with a high level of p-mTOR have a worse efficacy.
authors.affiliation: Peking University First Hospital, Beijing, China.
authors.forename: Liu-jing
authors.initials: LJ
authors.lastname: Ou
authors.forename: Chi
authors.initials: C
authors.lastname: Zhang
authors.forename: Xue-ning
authors.initials: XN
authors.lastname: Duan
authors.forename: Yin-hua
authors.initials: YH
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism*; D005260:Female; D006801:Humans; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D051059:PTEN Phosphohydrolase / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D012189:Retrospective Studies; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism*
chemical_list: C546842:MTOR protein, human; D051057:Proto-Oncogene Proteins c-akt; D058570:TOR Serine-Threonine Kinases; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human