Intensive evidence has uncovered that dysregulation of m6A regulators, including writers, erasers, and readers, can act as prognostic markers in TC. These regulators are involved in the tumor progression and function as useful tools to evaluate the prognosis of patients with differentiated TC [
79]. Particularly, the expression of HNRNPC is significantly elevated in TC, while WTAP, RBM15, YTHDC2, YTHDC1, FTO, METTL14, METTL3, ALKBH5, KIAA1429, YTHDF1, and ZC3H13 are remarkably decreased in tumor tissues; moreover, among these downregulated regulators, RBM15, KIAA1429, and FTO are used as a reference for prognostic analysis, which shows better performance in predicting the prognosis of TC with high accuracy [
59]. This established m6A-related three-gene prognostic model is also independent prognostic markers of overall survival in TC, which modulate the key signaling pathways of TC progression, such as proteolysis and immune response [
14,
80]. It is also found that IGF2BP2, STT3A, MTHFD1, and GSTM4 could be a prognostic signature of TC patients to predict disease-free survival [
74]. Li et al. further analyzed m6A regulators using The Cancer Genome Atlas databases and reported that the expression of two genes (WTAP and METTL16) are closely related to the histologic grading and TNM stage, and serve as a prognostic indicator for overall survival in TC patients [
81]. Of importance, dysregulated m6A regulators can be used in combination as the m6A score model for the prognostic analysis and treatment response, which reveals that patients with lower m6A score have prolonged overall survival and predicts the efficacy of immunotherapy [
82]. It has also been shown that m6A regulators can affect the prognostic analysis of TC by modulating specific ncRNAs. For example, the established m6A-related lncRNAs prognostic model acts as a novel predictor and shows good performance in predicting the progression-free survival and recurrence in TC patients [
83]. Bioinformation analysis proposed that m6A-related lncRNAs and mRNAs can influence gene mutation, immune cell infiltration and tumor microenvironment in TC [
84].
In conclusion, m6A regulators are dysregulated in TC and could be used as independent prognostic factors to optimize patient monitoring. However, there are still challenges in clarifying the optimal candidates for the early diagnosis and screening of TC. In consideration of the limitation of single m6A regulator acting as biomarker in different tumor stages and types, comprehensive analysis should be performed to identify the m6A regulator signatures as diagnostic biomarkers and prognostic indicators for patients with TC. In addition, multiple studies have screened m6A regulators based on analysis of public sequencing databases, reckoning without tumor heterogeneity and pathological types, which leads to drawing biased conclusions. Thus, more attention should be given to large-scale investigations for verifying the specificity and sensitivity of m6A regulators as biomarkers in TC patients.