RNA interference-mediated inhibition of erythropoietin receptor expression suppresses tumor growth and invasiveness in A2780 human ovarian carcinoma cells

Gyorgy Paragh, Suresh M. Kumar, Zsuzsa Rakosy, Soek Choel Choi, Xiaowei Xu, Geza Acs

Research output: Contribution to journalArticle

39 Citations (Scopus)

Abstract

Although recombinant human erythropoietin (rHuEpo) has revolutionized the treatment of anemia, recent clinical trials suggested that rHuEpo use may be associated with decreased survival in cancer patients. Although the expression of erythropoietin (Epo) receptor (EpoR) has been demonstrated in various human cancers, the effect of exogenous Epo on the growth and therapy resistance of EpoR-bearing tumor cells is unclear at present. In the current study, we examined the hypothesis that EpoR may contribute to tumor growth independent of Epo in A2780 human ovarian carcinoma cells. A2780 human ovarian carcinoma cells showed high levels of EpoR expression, but lacked expression of Epo mRNA and biologically active Epo protein under both normoxic and hypoxic conditions. Exogenous Epo did not stimulate EpoR- mediated signaling, proliferation, invasiveness, or resistance to cytotoxic drugs in A2780 cells. In contrast, specific inhibition of EpoR expression using a short hairpin RNA (shRNA) expression plasmid resulted in markedly reduced proliferation and inva- siveness in vitro. In addition, inhibition of EpoR expression led to abrogated in vivo ovarian cancer cell growth in a tumor xenograft system and resulted in decreased EpoR signaling. Our findings suggest that EpoR may be constitutively active in some cancer cells in the absence of Epo and provide the first evidence for a potential role of an Epo-indepen- dent, EpoR-mediated pathway in the growth of some human cancers

Original languageEnglish
Pages (from-to)1504-1514
Number of pages11
JournalAmerican Journal of Pathology
Volume174
Issue number4
DOIs
Publication statusPublished - Apr 2009

    Fingerprint

ASJC Scopus subject areas

  • Pathology and Forensic Medicine

Cite this