title: Chemoresponse assay for evaluating response to sunitinib in primary cultures of breast cancer.
abstract: OBJECTIVE
  Not all patient tumors respond equally to the same type of therapy. An in vitro chemoresponse assay that can suggest individualized tumor response to therapies, in this case sunitinib, can be a valuable guide for clinical decision-making.
  
  
  RESULTS
  The assay was shown to be sensitive and reproducible while differentiating renal cell lines based on sunitinib sensitivity and evaluating vendors' supply of the compound. Of the cultured breast cancer tumor specimens treated with sunitinib, ChemoFx classified 7.6% as responsive (R), 20.5% of specimens as intermediate responsive (IR), and 71.7% as non-responsive (NR).
  
  
  METHODS
  The ChemoFx(®) drug response marker (DRM) (Precision Therapeutics, Inc.) was carried out on SK-OV-3 cells treated with sunitinib to establish appropriate dose ranges and assay thresholds, and to evaluate vendor supplies of sunitinib. Once reference values were determined, the assay was applied to eight different renal cell lines treated with sunitinib, each of which was subsequently classified into responsive, intermediate responsive, and non-responsive groups. Next, ex vivo tumor samples from 39 clinically diagnosed breast cancer patients were grown in culture and assayed for their response to sunitinib using ChemoFx.
  
  
  CONCLUSIONS
  Chemoresponse assay assessment is an effective tool for evaluating sunitinib sensitivity in cultured cell lines as well as ex vivo breast cancer samples. An in vitro assay that may indicate an individual patient's clinical response to a chemotherapeutic agent can be beneficial in time, cost, and clinical outcome when therapeutic options are considered.
authors.affiliation: Precision Therapeutics, Pittsburgh, PA, USA. ssuchy@ptilabs.com
authors.forename: Sarah L
authors.initials: SL
authors.lastname: Suchy
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Hancher
authors.forename: Dakun
authors.initials: D
authors.lastname: Wang
authors.forename: Paul R
authors.initials: PR
authors.lastname: Ervin
authors.forename: Stacey L
authors.initials: SL
authors.lastname: Brower
mesh_terms: D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000378:metabolism*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D005260:Female; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D011758:Pyrroles / Q000494:pharmacology*; D011786:Quality Control; D012015:Reference Standards; D000077210:Sunitinib
chemical_list: D020533:Angiogenesis Inhibitors; D000970:Antineoplastic Agents; D007211:Indoles; D011758:Pyrroles; D000077210:Sunitinib