Table 1.

Mechanisms underlying the expression of SOD2 in different cancers.

Type of Cancer	SOD2 Expression	Underlying Mechanism	References
Bladder	Downregulated	Not determined	[59]
Brain	Downregulated	SOD2 hyperacetylation	[60]
	Upregulated	Not determined	[61,62,63]
Breast	Downregulated	p53 transcriptional inhibition Presence of DDB2 Epigenetics SOD2 hyperacetylation	[51,64,65,66]
	Upregulated	Loss of p53 NF-kB Nrf2 activation	[64,67,68]
Colorectal	Downregulated	Elevated AP1 at SNP promoter	[48]
	Upregulated	Not determined	[69,70]
Esophageal	Downregulated	Not determined	[71]
	Upregulated		[59]
Leukemia	Downregulated	Not determined	[59]
	Upregulated	ARNT activation	[44]
Liver	Downregulated	Calcium blocking of SIRT3	[72,73]
	Upregulated	Not determined	[59]
Lung	Downregulated	Ala16Val substitution	[74]
	Upregulated	Not determined	[59]
Lymphoma	Upregulated	Not determined	[75]
Melanoma	Downregulated	Loss of heterozygosity	[76]
Multiple Myeloma	Downregulated	Epigenetic silencing	[49,50]
Ovarian	Upregulated	Keap1 mutation Nrf2 activation	[52,57,77]
Pancreatic	Downregulated	Epigenetic silencing miR-301a activation Ala16Val substitution	[78,79,80]
	Upregulated	Not determined	[81]
Prostate	Upregulated	Low miR-17 expression	[70,82]
Renal Clear Cell	Downregulated	HIF-1α activation Oxidation	[83,84]
Sarcoma	Downregulated	Nitration	[59]
	Upregulated	Not determined	[59]
Tongue Squamous Cell	Downregulated	miR-222 activation	[85]
	Upregulated	c-myc activation	[86]

Ala: alanine; AP1: activated promoter 1; ARNT: aryl hydrocarbon receptor nuclear translocator; c-myc: cellular myelocytomatosis; DDB2: damaged DNA binding 2; HIF-1α: hypoxia-inducible factor 1-alpha; Keap1: kelch-like ECH-associated protein 1; miR: micro-RNA; NF-kB: nuclear factor-kappa B; Nrf2: nuclear factor erythroid 2–related factor 2; SIRT3: sirtuin 3; SNP: single nucleotide polymorphism; Val: Valine.