title: Patient-derived sialyl-Tn-positive invasive bladder cancer xenografts in nude mice: an exploratory model study.
abstract: BACKGROUND
  More than 70% of muscle invasive bladder cancers (MIBC) express the cell-surface antigen sialyl-Tn (sTn) that promotes motility and invasive potential of tumor cells. Effective drug testing models to optimize therapy against these tumors are warranted.
  
  
  METHODS
  Fragments of sTn-positive MIBC were subcutaneously engrafted into nude mice and expanded until the third passage. Histology and immunoexpression of tumor markers (p53, p63, Ki-67, CK20, sTn) were studied in order to evaluate tumor phenotype maintenance.
  
  
  RESULTS
  Tumor take rate was low in the first passage (1/9) but increased and became consistent, therefore suitable for drug testing, in the third passage (13/13). Histology and immunoexpression patterns were similar between primary tumors and xenografts. However, p53 and ki-67 levels increased with passages suggesting a selection of more proliferative clones. STn expression, even though decreased, was preserved in xenografts.
  
  
  CONCLUSIONS
  We describe the first patient-derived sTn-positive xenograft model to be used for drug testing and identification of prognostic biomarkers.
authors: Experimental Pathology and Therapeutics Group, Portuguese Institute of Oncology Francisco Gentil, Rua Dr. António Bernardino de Almeida 4200-072, Porto, Portugal. llarasantos@gmail.com.
authors: Carina
authors: C
authors: Bernardo
authors: Céu
authors: C
authors: Costa
authors: Teresina
authors: T
authors: Amaro
authors: Margarida
authors: M
authors: Gonçalves
authors: Paula
authors: P
authors: Lopes
authors: Rui
authors: R
authors: Freitas
authors: Fátima
authors: F
authors: Gärtner
authors: Francisco
authors: F
authors: Amado
authors: José Alexandre
authors: JA
authors: Ferreira
authors: Lúcio
authors: L
authors: Santos
mesh_terms: D000368:Aged; D000818:Animals; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000096:biosynthesis*; D014408:Biomarkers, Tumor / Q000032:analysis / Q000378:metabolism; D015153:Blotting, Western; D004195:Disease Models, Animal; D064593:Heterografts; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D001749:Urinary Bladder Neoplasms / Q000378:metabolism* / Q000473:pathology*
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D014408:Biomarkers, Tumor; C055491:sialosyl-Tn antigen
keywords: Human xenografts; animal models; drug testing; glycosylation; sialyl-Tn; urothelial cancer