Fig. 6

mtDNA-depleted ESCC and a DNMT inhibitor. A mtDNA-depleted ESCC cells treated with zebularine showed transformation from spindle to nonspindle cells. B The overall DNA methylation level was 10% lower after zebularine treatment in mtDNA-depleted ESCC cells. C There was similar expression of E-cadherin, N-cadherin, vimentin, and Zeb-1 in control cell lines. On the other hand, the expression of E-cadherin was higher after administration of zebularine in mtDNA-depleted ESCC cells, and mtDNA-depleted ESCC cells treated with zebularine had lower expression of N-cadherin, vimentin and Zeb-1 than cells not treated with zebularine. D The protein level of E-cadherin was increased by zebularine treatment in mtDNA-depleted ESCC cells, and the protein levels of N-cadherin and vimentin were decreased by zebularine treatment. *The densitometry of relative protein expression. E Zebularine administration to mtDNA-depleted ESCC cells significantly increased sensitivity to CDDP, 5-FU and DTX, while there was no difference in chemosensitivity in control cell lines treated with and not treated with zebularine. F The proliferation rates of mtDNA-depleted cells and control cells were significantly reduced by zebularine