BMC Cancer (Dec 2006)

Prognostic significance of multidrug-resistance protein (MDR-1) in renal clear cell carcinomas: A five year follow-up analysis

  • Strazzullo Viviana,
  • Nasti Mario,
  • Mezza Ernesto,
  • Rocchetti Romualdo,
  • D'Armiento Massimino,
  • Zamparese Rosanna,
  • Santoro Angela,
  • Pannone Giuseppe,
  • De Rosa Gaetano,
  • Altieri Vincenzo,
  • Staibano Stefania,
  • Mignogna Chiara,
  • Montanaro Vittorino,
  • Mascolo Massimo,
  • Bufo Pantaleo

DOI
https://doi.org/10.1186/1471-2407-6-293
Journal volume & issue
Vol. 6, no. 1
p. 293

Abstract

Read online

Abstract Background A large number of renal cancer patients shows poor or partial response to chemotherapy and the mechanisms have not been still understood. Multi-drug resistance is the principal mechanism by which many cancers develop resistance to chemotherapic drugs. The role of the multi-drug resistant transporter (MDR-1/P-glycoprotein), the gene product of MDR-1, and that one of the so-called multi-drug resistance associated protein (MRP), two energy-dependent efflux pumps, are commonly known to confer drug resistance. We studied MDR-1 expression in selected cases of renal cell carcinoma (RCC), clear cell type, with long-term follow-up, in order to establish its prognostic role and its possible contribution in the choice of post-surgical therapy. Methods MDR-1 has been studied by standard LSAB-HRP immunohistochemical technique, in paraffin embedded RCC samples. Protein expression has been compared to clinical and histopathological data and to disease specific survival of RCC patients, by Kaplan-Meier curve and Cox multivariate regression analyses. Results Two groups of RCCs were obtained by esteeming MDR-1 expression and disease specific survival (obtained with Kaplan-Meier curve and Cox multivariate regression analyses): the first one presents low or absent MDR-1 expression and good survival; the second one is characterized by high MDR-1 expression and significant poor outcome (p p p p Conclusion In our opinion, the results of this study well prove the relationship between MDR-1 expression and worse clinical prognosis in RCC, because MDR-1 over-expressing RCCs can be considered a group of tumours with a more aggressive behavior. This finding outlines a possible role of MDR-1 as prognostic factor, dependent and independent of multidrug resistance. These results could be useful to predict cancer evolution and to choose the appropriate treatment: this is another step that can stimulate further promising and interesting investigations on broader study population.