Oct-4 expression maintained stem cell properties in prostate cancer-derived CD133+MDR1+ cells
Purpose: CD133 (prominin-1), a 5-transmembrane glycoprotein, has recently been considered an important marker that represents the subset population of cancer stem-like cells. The purpose of the present study is to isolate cancerous stem-like cells from normal healthy volunteers and prostate cancer patients (CD133+) which also express MDR1 and to ascertain the influence of Oct-4 on ‘stem-ness' and differentiation of these CD133+ cells towards epithelium. Methods: CD133+ cells were isolated using magnetic beads from normal healthy volunteers and prostate cancer patients (NV-CD133+and PC-CD133+). The isolated cells were analyzed using flow cytometry and Western blot technique for CD133, MDR1 and Oct-4. CD133+MDR1+ cells were cultured in presence and absence of antihuman Oct-4 blocking antibody. Results: PC-CD133+ cells displayed higher Oct-4 expression with the ability to self-renew and may represent a reservoir with differentiation potential for generating prostate cancer cells. Furthermore, PCCD133 + cells highly co-expressed the multiple drug-resistant marker MDR1. The treatment with Oct-4 blocking antibody can specifically block the capability of PC-CD133+ cells to differentiate into prostate
epithelial cells bearing CD57. Conclusion: PC-CD133+ cells displayed a higher Oct-4 expression with the ability to self-renew and may represent a reservoir with differentiation potentials for progression of prostate cancer. The MDR1 expression of PC-CD133+ cells in vitro and in vivo is partially due to preferential activation of Oct-4 gene expression.
Keywords: Prostate cancer, Cancer stem-like cells, Oct-4, CD133, Multi-drug resistance1 (MDR1)
Tropical Journal of Pharmaceutical Research Vol. 8 (1) 2009: pp. 3-9