TABLE 1.

The main mechanisms of epigenetic regulation affecting KLF4 expression in tumors. The tumors where the mechanisms have been described are listed and the specific references reported.

Tumor		Epigenetic mechanism involved	References
Hematological tumors	Follicular lymphoma, diffuse large B-cell lymphoma, Burkitt lymphoma (NHL) and cHL. T-ALL	CpG island and global DNA methylation	Guan et al. (2010), Frazzi et al. (2017, 2022), Shen et al. (2017), Bialopiotrowicz et al. (2020), Frazzi et al. (2022)
Solid tumors	Lung adenocarcinoma, hepatocellular carcinoma, CRC, pancreatic cancer, OSCC, ESCC, HNSCC, urothelial cancer, renal cell carcinoma, medulloblastoma, gastric cancer	CpG island and global DNA methylation	Choi et al. (2006), Cho et al. (2007), Xu et al. (2008), Nakahara et al. (2010), Li et al. (2013, 2014, 2015), Wang et al. (2013), Chen et al. (2015), Zhou et al. (2015), Houessinon et al. (2016), Yang and Katz (2016), Xie et al. (2017), Zeng et al. (2018), Li et al. (2021), Cai et al. (2022), Wei et al. (2022)
Hematological tumors	Burkitt lymphoma, T-cell lymphoma	Histone H3K27 trymethylation	Han et al. (2017), Bialopiotrowicz et al. (2020)
	Acute myeloid leukemia	H3K4 demethylation	Faber et al. (2013)
Solid tumors	PCa	Histones H3K9me2 and H3K9me3	Lee et al. (2016)
	Lung cancer	Histone deacetylase inhibition	Yu et al. (2016)
	Glioblastoma, CRC, breast cancer	miRNAs	Miyoshi et al. (2010), Ogawa et al. (2015), Yang et al. (2015)
	Breast cancer	Circular RNA	Lu et al. (2020)