title: Characterization and drug resistance patterns of Ewing's sarcoma family tumor cell lines.
abstract: Despite intensive treatment with chemotherapy, radiotherapy and surgery, over 70% of patients with metastatic Ewing's Sarcoma Family of Tumors (EFT) will die of their disease. We hypothesize that properly characterized laboratory models reflecting the drug resistance of clinical tumors will facilitate the application of new therapeutic agents to EFT. To determine resistance patterns, we studied newly established EFT cell lines derived from different points in therapy: two established at diagnosis (CHLA-9, CHLA-32), two after chemotherapy and progressive disease (CHLA-10, CHLA-25), and two at relapse after myeloablative therapy and autologous bone marrow transplantation (post-ABMT) (CHLA-258, COG-E-352). The new lines were compared to widely studied EFT lines TC-71, TC-32, SK-N-MC, and A-673. These lines were extensively characterized with regard to identity (short tandem repeat (STR) analysis), p53, p16/14 status, and EWS/ETS breakpoint and target gene expression profile. The DIMSCAN cytotoxicity assay was used to assess in vitro drug sensitivity to standard chemotherapy agents. No association was found between drug resistance and the expression of EWS/ETS regulated genes in the EFT cell lines. No consistent association was observed between drug sensitivity and p53 functionality or between drug sensitivity and p16/14 functionality across the cell lines. Exposure to chemotherapy prior to cell line initiation correlated with drug resistance of EFT cell lines in 5/8 tested agents at clinically achievable concentrations (CAC) or the lower tested concentration (LTC): (cyclophosphamide (as 4-HC) and doxorubicin at CAC, etoposide, irinotecan (as SN-38) and melphalan at LTC; P<0.1 for one agent, and P<0.05 for four agents. This panel of well-characterized drug-sensitive and drug-resistant cell lines will facilitate in vitro preclinical testing of new agents for EFT.
authors: Childrens Center for Cancer and Blood Diseases, Childrens Hospital Los Angeles, Los Angeles, California, United States of America ; Saban Research Institute, Childrens Hospital Los Angeles, Los Angeles, California, United States of America ; Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America.
authors: William A
authors: WA
authors: May
authors: Rita S
authors: RS
authors: Grigoryan
authors: Nino
authors: N
authors: Keshelava
authors: Daniel J
authors: DJ
authors: Cabral
authors: Laura L
authors: LL
authors: Christensen
authors: Jasmine
authors: J
authors: Jenabi
authors: Lingyun
authors: L
authors: Ji
authors: Timothy J
authors: TJ
authors: Triche
authors: Elizabeth R
authors: ER
authors: Lawlor
authors: C Patrick
authors: CP
authors: Reynolds
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics / Q000378:metabolism*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects* / Q000235:genetics; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D012512:Sarcoma, Ewing / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D025803:Tumor Suppressor Protein p14ARF / Q000235:genetics / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; D019941:Cyclin-Dependent Kinase Inhibitor p16; C495901:TP53 protein, human; D025803:Tumor Suppressor Protein p14ARF; D016159:Tumor Suppressor Protein p53