To achieve this, we performed methylation-specific polymerase chain reaction assays (MSPs) of the NSCLC cell lines relative to NAC to quantitatively assess unmethylated and methylated allelic fractions of TBX4 and TBX5, which we found above to be the most methylated members of the TBX2 subfamily in NSCLC. Here, TBX4 is linked to non-small cell lung carcinoma.