title: In vivo biological effects of pegfilgrastim after myelosuppressive chemotherapy in breast cancer.
abstract: BACKGROUND
  No exhaustive data are available on the in vivo biological effects of pegfilgrastim utilized in dose-dense chemotherapy (CT). The cytokinetic effects exerted in a multicyclic CT program by this cytokine on CD34+/38+ peripheral blood (PB) progenitor cells was the focus of this study.
  
  
  METHODS
  PB samples from 19 breast cancer patients treated with 4 courses of docetaxel and epirubicin followed by pegfilgrastim were studied. The absolute number of CD34+/38+ circulating progenitor cells (CPCs) along with the percentage undergoing GO/G1, S and G2-M phases of the cell cycle or showing apoptotic features, were evaluated at baseline, after the first and before the fourth CT course using a dedicated flow cytometric technique.
  
  
  CONCLUSIONS
  Pegfilgrastim, after CT, exerted stimulatory effects on the cell cycle status of PB CD34+/38+ CPCs, at the same time protecting them from apoptosis. This was particularly evident 7 days after administration and tended to decrease one week later, without additional cytokinetic changes during the subsequent CT courses.
authors.affiliation: Flow Cytometry and Cell Therapy Unit, Medical Oncology, University and Foundation IRCCS San Matteo, PAVIA, Italy. m.danova@smatteo.pv.it
authors.forename: Marco
authors.initials: M
authors.lastname: Danova
authors.forename: Katia
authors.initials: K
authors.lastname: Bencardino
authors.forename: Mariangela
authors.initials: M
authors.lastname: Manzoni
authors.forename: Donatella
authors.initials: D
authors.lastname: Grasso
authors.forename: Sara
authors.initials: S
authors.lastname: Mariucci
authors.forename: Bianca
authors.initials: B
authors.lastname: Rovati
mesh_terms: D051997:ADP-ribosyl Cyclase 1 / Q000097:blood; D000328:Adult; D018952:Antigens, CD34 / Q000097:blood; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000601:surgery; D003131:Combined Modality Therapy; D000077143:Docetaxel; D015251:Epirubicin / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D000069585:Filgrastim; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage / Q000627:therapeutic use*; D006412:Hematopoietic Stem Cells / Q000187:drug effects; D006801:Humans; D008875:Middle Aged; D009503:Neutropenia / Q000139:chemically induced / Q000188:drug therapy*; D011092:Polyethylene Glycols; D011994:Recombinant Proteins; D043823:Taxoids / Q000008:administration & dosage / Q000009:adverse effects
chemical_list: D018952:Antigens, CD34; D011994:Recombinant Proteins; D043823:Taxoids; D016179:Granulocyte Colony-Stimulating Factor; D000077143:Docetaxel; C455861:pegfilgrastim; D011092:Polyethylene Glycols; D015251:Epirubicin; D051997:ADP-ribosyl Cyclase 1; D000069585:Filgrastim