TY - JOUR
T1 - SLUG silencing increases radiosensitivity of melanoma cells in vitro
AU - Arienti, Chiara
AU - Tesei, Anna
AU - Carloni, Silvia
AU - Ulivi, Paola
AU - Romeo, Antonino
AU - Ghigi, Giulia
AU - Menghi, Enrico
AU - Sarnelli, Anna
AU - Parisi, Elisabetta
AU - Silvestrini, Rosella
AU - Zoli, Wainer
PY - 2013/4
Y1 - 2013/4
N2 - Background: Melanoma radioresistance has been attributed to the presence of tumor cells with highly efficient DNA damage repair mechanisms. We examined the expression of genes involved in DNA damage repair and DNA damage sensing, and assessed their modulation by SLUG silencing, which is potentially capable of increasing radiosensitivity. Methods: Two melanoma cell lines (M14 and M79) were used to evaluate in vitro radiation-induced cytotoxicity before and after SLUG silencing. mRNA expression levels of BRCA1, ERCC1, DNA-PK, PARP, MGMT, ATM and TGM2 were determined by real-time RT-PCR, and protein expression levels of SLUG, caspase 3, p21, PUMA and pMAPK by Western blotting. Results: The cytotoxic effect of radiation was high in M14 and low in M79 cells. SLUG silencing increased the interference of radiation on cell cycle distribution and cell killing by 60 % and 80 % in M79 cells after a 2.4 Gy and 5 Gy radiation dose, respectively. It also led to a significant inhibition of expression of genes involved in DNA damage repair and DNA damage sensing in all cell lines maintained after radiation. An almost total inhibition was observed for TGM2, which is expressed at a high basal level in the most radioresistant cell line (M79). Protein expression of PUMA was induced by radiation and was enhanced after SLUG silencing. Conclusions: Our results reveal a pivotal role of SLUG in regulating a cellular network involved in the response to DNA damage, and highlight the importance of TGM2 in radiosensitivity modulation. SLUG silencing appears to increase radiation sensitivity of the melanoma cells tested.
AB - Background: Melanoma radioresistance has been attributed to the presence of tumor cells with highly efficient DNA damage repair mechanisms. We examined the expression of genes involved in DNA damage repair and DNA damage sensing, and assessed their modulation by SLUG silencing, which is potentially capable of increasing radiosensitivity. Methods: Two melanoma cell lines (M14 and M79) were used to evaluate in vitro radiation-induced cytotoxicity before and after SLUG silencing. mRNA expression levels of BRCA1, ERCC1, DNA-PK, PARP, MGMT, ATM and TGM2 were determined by real-time RT-PCR, and protein expression levels of SLUG, caspase 3, p21, PUMA and pMAPK by Western blotting. Results: The cytotoxic effect of radiation was high in M14 and low in M79 cells. SLUG silencing increased the interference of radiation on cell cycle distribution and cell killing by 60 % and 80 % in M79 cells after a 2.4 Gy and 5 Gy radiation dose, respectively. It also led to a significant inhibition of expression of genes involved in DNA damage repair and DNA damage sensing in all cell lines maintained after radiation. An almost total inhibition was observed for TGM2, which is expressed at a high basal level in the most radioresistant cell line (M79). Protein expression of PUMA was induced by radiation and was enhanced after SLUG silencing. Conclusions: Our results reveal a pivotal role of SLUG in regulating a cellular network involved in the response to DNA damage, and highlight the importance of TGM2 in radiosensitivity modulation. SLUG silencing appears to increase radiation sensitivity of the melanoma cells tested.
KW - DNA repair
KW - Melanoma
KW - Radiation
KW - SLUG gene
KW - TGM2
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U2 - 10.1007/s13402-012-0120-6
DO - 10.1007/s13402-012-0120-6
M3 - Article
C2 - 23250725
AN - SCOPUS:84876467307
VL - 36
SP - 131
EP - 139
JO - Cellular oncology (Dordrecht)
JF - Cellular oncology (Dordrecht)
SN - 2211-3428
IS - 2
ER -