Identification of CD133-Positive Radioresistant Cells in Atypical Teratoid/ Rhabdoid Tumor

Abstract

Atypical teratoid/rhabdoid tumor (AT/RT) is an extremely malignant neoplasm in the central nervous system (CNS) which occurs in infancy and childhood. Recent studies suggested that CD133 could be considered a marker for brain cancer stem-like cells (CSCs). However, the role of CD133 in AT/RT has never been investigated. Herein we report the isolation of CD133-positive cells (CD133+), found to have the potential to differentiate into three germ layer tissues, from tissues of nine AT/RT patients. The migration/invasion/malignancy and radioresistant capabilities of CD133+ were significantly augmented when compared to CD133−. The clinical data showed that the amount of CD133+ in AT/RTs correlated positively with the degree of resistance to radiation therapy. Using cDNA microarray analysis, the genotoxic–response profiles of CD133+ and CD133− irradiated with 10 Gy ionizing radiation (IR) were analyzed 0.5, 2, 6, 12 and 24 h post-IR. We then validated these microarray data and showed increased phosphorylation after IR of p-ATM, p-RAD17, and p-CHX2 as well as increased expression of BCL-2 protein in CD133+ compared to CD133−. Furthermore, we found that CD133+ can effectively resist IR with cisplatin- and/or TRAIL-induced apoptosis. Immunohistochemical analysis confirmed the up-regulated expression of p-ATM and BCL-2 proteins in IR-treated CD133+ xenotransgrafts in SCID mice but not in IR-treated CD133−. Importantly, the effect of IR in CD133+ transplanted mice can be significantly improved by a combination of BCL-2 siRNA with debromohymenialdisine, an inhibitor of checkpoint kinases. In sum, this is the first report indicating that CD133+ AT/RT cells demonstrate the characteristics of CSCs. The IR-resistant and anti-apoptotic properties in CD133+ may reflect the clinical refractory malignancy of AT/RTs and thus the activated p-ATM pathway and BCL-2 expression in CD133+ could be possible targets to improve future treatment of deadly diseases like AT/RT.

Noninvasive positron emission tomography and fluorescence imaging of CD133 + tumor stem cells

“…In the latter study, a considerable proportion of tumors contained >10% or even >25% AC133 + cells, and the AC133+ cells tended to organize in clusters. For medulloblastomas, 6-21% AC133 + cells have been reported (19), and for teratoid/rhabdoid brain tumors 1-36% have been reported at diagnosis and 30-70% at relapse (42). For colon cancer, 2-19% AC133 + cells were reported, compared with 0.4-2% in the surrounding tissue (20), and for ovarian cancer the reported range is 0.3-35% (43).…”

Cucurbitacin I inhibits tumorigenic ability and enhances radiochemosensitivity in nonsmall cell lung cancer‐derived CD133‐positive cells

“…The cells from samples that were dissociated from the patients with NSCLC were labeled with 1 mL CD133/L micromagnetic beads per 1 million cells using the CD133 cell isolation kit (Miltenyi Biotech, Auburn, Calif). Because serum-free medium culture allowed the selection of undifferentiated colon, glioblastoma, or lung cancer stem and progenitor cells, 8,11,25 CD133-positive cells were cultured in a medium consisting of serum-free Dulbecco modified Eagle medium (DMEM)/F-12 medium (Gibco-BRL, Gaithersburg, Md), N2 supplement (R&D Systems Inc., Minneapolis, Minn), 10 ng/mL human recombinant basic fibroblast growth factor (bFGF0 (R&D Systems Inc.), and 10 ng/mL epidermal growth factor (EGF) (R&D Systems Inc.). To exclude potential contamination by hematopoietic and endothelial cells, samples were examined using antiepithelial-specific antigen fluorescein isothiocyanate (Biomeda).…”

“…CD133-positive and CD133-negative NSCLC cells were transfected with a lentiviral vector that contained the GFP gene (transfection efficiency was 80%). 25 First, we injected 1 Â 10 5 CD133-positive/GFP Tumor volumes in NSCLC-CD133þ-transplanted mice that received either cucurbitacin I (100 nM) plus ionizing radiation (IR) (4 grays Gy) or cisplatin (Cis.) alone were significantly lower than the tumor volumes in mice that received IR or drug only (P < .01).…”

The Stem Cell Environment: Kinetics, Signaling and Markers

“…Interestingly, when CD133+ cells were irradiated with 3Gy, they were able to initiate tumors with almost the same efficacy than the non-irradiated CD133+ cells. A clinical study in atypical teratoid/rhabdoid tumors demonstrated a correlation of the amount of immunohistochemically detected CD133+ cells with resistance to combined chemoradiation and decreased survival (Chiou et al 2008). These data are supported by evaluations of glioma (Murat et al 2008) and rectal cancer patients (Wang et al 2009).…”