title: Changes of biological features in breast cancer cells determined by primary chemotherapy.
abstract: BACKGROUND
  To evaluate the changes in the biological features of breast cancer cells induced by primary chemotherapy (PCT) and their possible relationship with the response to therapy we performed an extensive immunohistochemical study before and after PCT.
  
  
  METHODS
  PCT was administered to 29 women with breast cancer. On specimens obtained by tru-cut and post-chemotherapy surgery we analyzed the following parameters: histology, histologic grade, apoptotic index, hormone receptor levels, Ki67, PCNA, EGFr, bcl-2, p53, p170. The significance of the changes induced by PCT and their correlations with the type of response were evaluated.
  
  
  RESULTS
  Twelve patients achieved a partial response with PCT. No baseline biological parameter correlated with the type of response. After PCT we observed a significant increase in the apoptotic index (p = 0.000), PCNA (p = 0.036), EGFr (p = 0.005), and p170 expression (p = 0.001), regardless of the type of chemotherapy administered (anthracyclines, 25 cases, or CMF, 4 cases). Responder patients displayed a significant decrease in ER levels (p = 0.015), whereas in non responders there was an increase in PCNA (p = 0.008) and EGFr expression (p = 0.002). The apoptotic index and p170 expression rose after PCT regardless of the type of response.
  
  
  CONCLUSIONS
  PCT induced significant variations in the phenotype of breast cancer cells. These changes might reflect the selection of new neoplastic clones with different biological properties and so could facilitate the choice of appropriate chemotherapy agents.
authors.affiliation: Department of Medical, Oncological and Radiological Sciences, University of Modena, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Frassoldati
authors.forename: F
authors.initials: F
authors.lastname: Adami
authors.forename: C
authors.initials: C
authors.lastname: Banzi
authors.forename: M
authors.initials: M
authors.lastname: Criscuolo
authors.forename: L
authors.initials: L
authors.lastname: Piccinini
authors.forename: V
authors.initials: V
authors.lastname: Silingardi
mesh_terms: D000328:Adult; D000368:Aged; D000903:Antibiotics, Antineoplastic / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology*; D003520:Cyclophosphamide / Q000008:administration & dosage; D004317:Doxorubicin / Q000627:therapeutic use*; D066246:ErbB Receptors / Q000032:analysis; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D007150:Immunohistochemistry; D008727:Methotrexate / Q000008:administration & dosage; D008875:Middle Aged; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis
chemical_list: D000903:Antibiotics, Antineoplastic; D018809:Proliferating Cell Nuclear Antigen; D004317:Doxorubicin; D003520:Cyclophosphamide; D066246:ErbB Receptors; D005472:Fluorouracil; D008727:Methotrexate