The GANT61, a GLI inhibitor, induces caspase-independent apoptosis of SK-N-LO cells.
GANT61 is a small-molecule inhibitor of glioma-associated oncogene 1 (GLI1)- and GLI2-mediated transcription at the nuclear level that exerts its effect by preventing DNA binding. It has been demonstrated to induce cell death against Ewing's sarcoma family tumor (ESFT) cell lines in a dose-dependent manner. The most sensitive cell line was SK-N-LO, which expresses the EWS-FLI1 fusion gene. SK-N-LO cells treated with GANT61 showed cellular and nuclear morphological changes, including cell shrinkage, chromatin condensation and nuclear fragmentation, in a concentration-dependent manner, as visualized by Hoechst 33342 staining. Furthermore, annexin V-propidium iodide (PI) double-staining revealed a significant increase in the number of late apoptotic cells. GANT61 induced a significant decrease in the proportion of cells in the S phase. Significant decrease of the protein levels of GLI2, survivin, cyclin A and claspin, and significant increase of p21 expression was also observed in the cells treated with GANT61. Moreover, poly (ADP-ribose) polymerase (PARP) cleavage was observed, but no cleavage of caspase-3 or -7, or any change in the expressions of Bcl-2 or p53 were observed. These findings suggest that GANT61 induces cell death of SK-N-LO cells in a caspase-independent manner, by inhibiting DNA replication in the S phase.
School of Pharmacy, Nihon University.
Takahiro
T
Matsumoto
Keiichi
K
Tabata
Takashi
T
Suzuki
D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D053179:Caspase 7 / Q000378:metabolism; D020169:Caspases / Q000378:metabolism*; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D019925:Cyclin A / Q000378:metabolism; D004790:Enzyme Induction / Q000187:drug effects*; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D011725:Pyridines / Q000494:pharmacology*; D011743:Pyrimidines / Q000494:pharmacology*; D000077022:Survivin; D014157:Transcription Factors / Q000037:antagonists & inhibitors* / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis; D000071676:Zinc Finger Protein GLI1; D020741:rho GTP-Binding Proteins / Q000096:biosynthesis
D048868:Adaptor Proteins, Signal Transducing; C107489:BIRC5 protein, human; C488158:CLSPN protein, human; D019925:Cyclin A; C551027:GANT 61; C400551:GLI1 protein, human; D051034:Inhibitor of Apoptosis Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D011725:Pyridines; D011743:Pyrimidines; D000077022:Survivin; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53; D000071676:Zinc Finger Protein GLI1; D011065:Poly(ADP-ribose) Polymerases; D053148:Caspase 3; D053179:Caspase 7; D020169:Caspases; D020741:rho GTP-Binding Proteins