title: Efficacy of nab-paclitaxel does not seem to be associated with SPARC expression in metastatic breast cancer.
abstract: OBJECTIVE
  To evaluate the predictive value of the expression of the secreted protein acidic and rich in cysteine (SPARC) for nab-paclitaxel in metastatic breast cancer (MBC).
  
  
  METHODS
  Forty-four patients with progressive MBC were prospectively treated with nab-paclitaxel. Expression of SPARC in tumor cells was assessed by an immunoreactive score, integrating staining intensity and percentage of positive tumor cells; expression in stroma based on staining intensity. SPARC serum levels were determined before 1st and 2nd cycle of nab-paclitaxel and at progression. By applying several cut-offs the association between SPARC expression or serum levels and clinical end-points was analyzed.
  
  
  RESULTS
  No clear association between expression of SPARC in primary or metastatic tumor tissue or in serum and any clinical end-point could be detected regardless of the various cut-offs applied.
  
  
  CONCLUSIONS
  Efficacy of nab-paclitaxel in MBC does not seem to be associated with expression of SPARC in tumor tissues or serum.
authors.affiliation: National Center for Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany Department of Gynecology and Obstetrics, University Hospital Heidelberg, Heidelberg, Germany andreas.schneeweiss@med.uni-heidelberg.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schneeweiss
authors.affiliation: National Center for Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany Department of Gynecology and Obstetrics, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Seitz
authors.affiliation: National Center for Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany Department of Gynecology and Obstetrics, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Smetanay
authors.affiliation: National Center for Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany Department of Gynecology and Obstetrics, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Schuetz
authors.affiliation: National Center for Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Jaeger
authors.affiliation: Biometrics Department, ClinAssess GmbH, Leverkusen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Bachinger
authors.affiliation: Central Laboratory, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Zorn
authors.affiliation: Department of Pathology, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Sinn
authors.affiliation: National Center for Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany Department of Gynecology and Obstetrics, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Frederik
authors.initials: F
authors.lastname: Marmé
mesh_terms: D000328:Adult; D000368:Aged; D000418:Albumins / Q000008:administration & dosage*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D015676:Osteonectin / Q000378:metabolism*; D017239:Paclitaxel / Q000008:administration & dosage*; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate
chemical_list: C520255:130-nm albumin-bound paclitaxel; D000418:Albumins; D014408:Biomarkers, Tumor; D015676:Osteonectin; C577241:SPARC protein, human; D017239:Paclitaxel
keywords: Metastatic breast cancer; SPARC; chemotherapy; nab-paclitaxel