Altered expression of c-IAP1, survivin, and Smac contributes to chemotherapy resistance in thyroid cancer cells.

Giorgio Stassi, Elena Tirrò, Maria Letizia Consoli, Laura Sciacca, Paolo Vigneri, Francesco Frasca, Livia Manzella, Michele Massimino, Luigi Messina, Luisa Vicari, Angelo Messina, Letizia Manzella, Luigi Messina, Luigia Sciacca

Risultato della ricerca: Article

84 Citazioni (Scopus)

Abstract

Resistance to chemotherapy predicts an unfavorable outcome for patients with radioiodine-insensitive thyroid cancer. To investigate the mechanisms underlying this resistance, we evaluated the expression of four different inhibitor of apoptosis proteins, and their antagonist, Smac, in thyroid cancer cells that survived 48 hours of exposure to cisplatin, doxorubicin, or taxol. We found high levels of c-IAP1 after cisplatin treatment and increased expression of survivin following exposure to doxorubicin. Cells that endured treatment with taxol showed reduced expression of Smac and released minimal amounts of this protein from the mitochondria. Down-regulation of c-IAP1 and survivin increased the cytotoxicity of cisplatin and doxorubicin, whereas overexpression of Smac improved the efficacy of taxol. Finally, thyroid cancer cells permanently resistant to doxorubicin or cisplatin showed increased expression of C-IAP1 and survivin, respectively. However, silencing of these proteins by RNA interference restored sensitivity to doxorubicin and cisplatin. Thus, in thyroid cancer cells, early resistance to chemotherapeutic agents requires high levels of c-IAP1 and survivin and low levels of Smac. Furthermore, increased expression of c-IAP1 and survivin contributes to the acquisition of permanent resistance to cytotoxic compounds.
Lingua originaleUndefined/Unknown
pagine (da-a)4263-4272
RivistaCancer Research
Volume66
Stato di pubblicazionePublished - 2006

All Science Journal Classification (ASJC) codes

  • Oncology
  • Cancer Research

Cita questo