title: Adipophilin as prognostic biomarker in clear cell renal cell carcinoma.
abstract: OBJECTIVE
  To study the expression of adipophilin (PLIN2), a lipid storage-associated cell protein, in different subtypes of renal cell cancer and to elucidate its prognostic value.
  
  
  METHODS
  Two-hundred-seventy-five patients with renal cell carcinoma (RCC) were included in this study. Immunohistochemistry with a polyclonal antibody to adipophilin was used on the tissue microarray (formalin-fixed, paraffin-embedded tissue) for detection of adipophilin. Median follow-up time was 91 (range 1-159) months in the whole cohort and 100 (1-159) months for patients with clear-cell RCC. Additional validation for adipophilin was performed using publicly available gene expression data for clear cell RCC from The Cancer Genome Atlas (TCGA).
  
  
  RESULTS
  Adipophilin expression was detected in 14.3% of papillary RCC, in 0% of chromophobe RCC and in 58.7% of clear-cell RCC in the cytoplasm or at the membrane. Only membrane expression was correlated with other clinical parameters (pT-stage, pN-stage, R-status, sex) and showed a prognostic significance in univariate analysis with regard to overall survival of patients with clear cell subtype (HR 2.90, 95% CI 1.55-5.42, p=0.001), which failed significance on multivariate analysis. mRNA expression of PLIN2 on TCGA data using best selected cut-off was prognostically significant in both univariate (HR 1.76, 95% CI 1.28-2.42, p = 0.0005) and multivariate analyses (HR 1.46, 95% CI 1.05-2.04, p = 0.0257).
  
  
  CONCLUSIONS
  Adipophilin is a novel and still understudied prognostic biomarker in clear cell renal cell carcinoma which deserves further study.
authors.affiliation: Institute for Pathology, University Hospital Bonn, Bonn, Germany.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Tolkach
authors.affiliation: Institute for Pathology, University Hospital Bonn, Bonn, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Lüders
authors.affiliation: Institute for Pathology, University Hospital Bonn, Bonn, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Meller
authors.affiliation: Berlin Institute of Urologic Research, Berlin, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Jung
authors.affiliation: Berlin Institute of Urologic Research, Berlin, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Stephan
authors.affiliation: Institute for Pathology, University Hospital Bonn, Bonn, Germany.
authors.forename: Glen
authors.initials: G
authors.lastname: Kristiansen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D063646:Carcinogenesis; D002292:Carcinoma, Renal Cell / Q000175:diagnosis* / Q000473:pathology; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007680:Kidney Neoplasms / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D000070780:Perilipin-2 / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D011379:Prognosis
chemical_list: D014408:Biomarkers, Tumor; D000070780:Perilipin-2
keywords: PLIN2; adipophilin; clear cell; perilipin 2; renal cell carcinoma