Examples of potential critical methylation changes include the following: GATA2 expression (methylation was positively correlated with expression among the TCGA samples) has been shown to be elevated in breast cancer and serves to repress PTEN expression [35], HOXB2 for which increased methylation is associated with bladder cancer invasiveness [36], and the long non-coding RNA HOTAIR, which demonstrated increases in methylation associated with progression and was also positively correlated with expression in TCGA tumors. This evidence concerns the gene PTEN and breast cancer.