TABLE 1.

The most common mutations of epigenetic factors and their effect on the tumor microenvironment.

Epigenetic modifiers	Function	Mutation frequency	Affected genes linked to immune signaling	Changes in TME
KMT2D	H3K4 methyltransferase	30% DLBCL	CD40, IL-10-IL6	Increase of exhausted CD8+ T cells Brisou el al. (2018) and of effector immune cells Wang et al. (2020)
		80% FL		Decrease in Treg cells Wang et al. (2020)
KMT2C	H3K4 methyltransferase	5% DLBCL	IL1, GPX8, GSTA4, GSSTT1, ETS/PU.1, IRF, RUNX, AP-1	Increase of CD8+ T cells and of effector immune cells Liu et al. (2021); Zhang et al. (2021)
		13% FL		Decrease in Treg cells Liu et al. (2021); Zhang et al. (2021)
CREBBP	Lysine acetyltransferase	15% DLBCL	MHC II, CIITA, CD74, CD40, PDL1, IFN	Decrease CD4+ T cells Green el al. (2015)
		60% FL
EP300	Lysine acetyltransferase	5% DLBCL	E2F1, CDC25B, CDKN1A, PDNA, CDT1, DNA2, RADE51, XRCC1	Increase of M2 macrophages Huang el al. (2021)
		15% FL		Decrease in Treg cells Liu et al. (2013)
EZH2	H3K27 methyltransferase	25% DLBCL	CIITA, NLRC5, Th1-type chemokines	Increase in FDCs Béguelin et al. (2020)
		10–25% FL		Decrease in TFH cells Béguelin et al. (2020)
TET2	Methylcytosine dioxygenase 2	10% DLBCL	CD40, IL-10-IL6, MHC II	Increase of CD8+ T cells memory Tsagaratou et al. (2017) and NK cells Carty et al. (2018)
		2% FL		Decrease T cells Pan et al. (2017) and macrophages Lee el al., 2021
ARID1A	SWI/SNF component	10% DLBCL	IFN, PDL1	Increase of CD8+ T cells Shen et al. (2018)
		11% FL
HIST1H1C/E	Linker histone	26% DLBCL	NANOG, SOX2, PRC2	Not yet explored
		44% FL