Effects of 60Co gamma-rays on human osteoprogenitor cells.
BACKGROUND
Radiation therapy is one of the most efficient treatments of neoplastic diseases used worldwide. However, patients who undergo radiotherapy may develop side effects that can be life threatening because tissue complications caused by radiation-induced stem cell depletion may result in structural and functional alterations of the surrounding matrix. This treatment also damages the osteogenic activity of human bone marrow by suppressing osteoblasts, leading to post-irradiation sequelae. Even if widely used in oncology, there is still little information on the fate and potential therapeutic efficacy of electromagnetic rays.


METHODS
We addressed this question using both human mesenchymal stem cells and osteoblasts. Monoclonal antibody characterization identified specific surface markers for stem cells (SSEA-4, CD29, CD105, Oct 3, Nanog and SOX2) and osteoblasts (Osteopontin and Osteonectin). The technique of anti-alkaline phosphatase FITC-staining demonstrated the presence of this specific ectoenzyme. Cells were cultured in complex osteogenic medium (DMEM, 15% fetal calf serum, non-essential amino acids, L-glutamine, dexametazone, ascorbic acid, insulin, TGF-beta, BMP-2 and beta-glycero-phosphate) after being irradiated at 0.5 Gy, 1 Gy, 2 Gy and 4 Gy using a Theratron 1000 60Co source. The viability of irradiated cells was assessed using Trypan Blue staining. The comparison between cell lineages after culture in osteogenic media regarding phenotypical characterization and the intensity of the mineralization process included histology stainings (Alizarin Red S, Alcian Blue and von Kossa), and the MTT-based proliferation assay.


RESULTS
After irradiation, the proliferation and differentiation of osteoprogenitor cells is dose-dependent.


CONCLUSIONS
This study is one among the first papers investigating the biophysics of low-dose gamma-irradiation on stem cell culture, focusing on the potential applications in radiation oncology and various palliative treatments.
Tomuleasa
C I
CI
Laboratory of Experimental Radiotherapy and Stem Cell Culture, Prof. Dr. Ion Chiricuta Cancer Center, Cluj-Napoca, Romania.
Foris
V
V
Soriţău
Olga
O
Páll
Emöke
E
Fischer-Fodor
Eva
E
Lung-Illes
V
V
Brie
Ioana
I
Virág
Piroska
P
Perde-Schrepler
Maria
M
Postescu
I D
ID
Cherecheş
Gabriela
G
Barbos
Otilia
O
Tatomir
Corina
C
D000880:Anthraquinones / Q000378:metabolism; D001854:Bone Marrow Cells / Q000166:cytology; D002113:Calcification, Physiologic / Q000528:radiation effects; D016923:Cell Death / Q000528:radiation effects; D002454:Cell Differentiation / Q000528:radiation effects; D002465:Cell Movement / Q000528:radiation effects; D049109:Cell Proliferation / Q000528:radiation effects; D048430:Cell Shape / Q000528:radiation effects; D002478:Cells, Cultured; D003037:Cobalt Radioisotopes; D005720:Gamma Rays; D006801:Humans; D007150:Immunohistochemistry; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000528:radiation effects*; D010006:Osteoblasts / Q000166:cytology / Q000528:radiation effects*; D013194:Staining and Labeling; D014343:Trypan Blue / Q000378:metabolism
D000880:Anthraquinones; D003037:Cobalt Radioisotopes; C010078:alizarin; D014343:Trypan Blue