In esophageal squamous cell carcinoma (ESCC), the m5C methyltransferase NSUN2 can upregulate the expression of TIGAR and GRB2, which increases the production of glutathione, reduces cell apoptosis, and promotes cell proliferation, collectively leading to chemoresistance in ESCC.552 Studies have also found that m5C reader proteins are associated with chemoresistance. This evidence concerns the gene GRB2 and esophageal squamous cell carcinoma.