Thyroid Cancer-Associated Mitochondrial DNA Mutation G3842A Promotes Tumorigenicity via ROS-Mediated ERK1/2 Activation

Figure 3

Effects of the G3842A mutation on tumorigenicity in vitro. (a) PCR-RFLP assays confirmed the established 143b cell line with G3842A mutation (MUT). After enzymatic digestion, DNA from 143b cells without the G3842A mutation (WT) yielded fragments of 693 bp and 139 bp. 143b cells with and without G3842A mutation were cultured in vitro under (b) 20% and (c) 1% O₂ conditions, and the cell number was counted daily. Colony formation assays showing increased proliferation of MUT cells as compared with WT cells under both (d) 20% and (e) 1% O₂ conditions. Transwell assays were performed to evaluate the migration and invasion abilities of MUT and WT cells under (f) 20% and (g) 1% O₂ conditions. (h) Wound healing assays further validated the increased migration ability of MUT cells. The wound healing capacity was calculated as follows: . Data are presented as of at least three replicates. , , and . PCR-RFLP: polymerase chain reaction-restriction fragment length polymorphism; SEM: standard error of the mean.

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