Figure S1. Heat map of GSE79973, comparing between 10 gastric cancer tissues and 10 normal tissues. The GSE79973 included 10 patients. Every sample was from the same patient. These were patient 1 (32C,33N), patient 2 (34C,35N)….patient 9 (48C,49N), patient 10 (50C,51N), respectively. Columns with even numbers are for gastric cancer tissue and those with odd numbers are for normal tissues. C, cancer; N, normal. Figure S2. mRNA expression levels of histone modification‑ associated genes in different types of cancer according to the Oncomine database. Upregulation is indicated in red and downregulation in blue. Table SI. Basic characteristics and function of histone modification enzymes and associated genes. A, HDACs and associated genes Protein Gene Location Exon mass (kDa) Encoding protein and biological function HDAC1 1p35.2‑p35.1 14 55.11 Encodes a component of the HDAC complex. Interacts with retinoblastoma tumor‑suppressor protein and controls cell proliferation and differentiation. Together with metastasis‑associated protein‑2, it deacetylates p53 and modulates its effect on cell growth and apoptosis. HDAC2 6q21 17 55.37 Performs deacetylation of lysine residues at the N‑terminal regions of core histones (H2A, H2B, H3 and H4). Forms transcriptional repressor complexes by associating with proteins, including YY1. Participates in transcriptional regulation, cell cycle progression and developmental events. HDAC3 5q31.3 15 48.81 HDAC with a potential tumor suppressor gene function. Represses transcription when tethered to a promoter through its binding with YY1. Downregulates the function of p53 and modulates cell growth and apoptosis. HDAC4 2q37.3 37 106.39 Class II of the HDAC/AcuC/aphA family. Represses transcription; binds DNA through transcription factors MEF2C and MEF2D. Interacts with RbAp48 and HDAC3. HDAC5 17q21.31 30 122.02 Class II of the HDAC/AcuC/aphA family. Represses transcription. Coimmunoprecipitates only with HDAC3 family member. Interacts with MEF2 proteins to repress expression of MEF2‑dependent genes. HDAC6 Xp11.23 32 131.46 Class II of the HDAC/AcuC/aphA family. Contains an internal duplication of two catalytic domains, which appear to function independently of each other. Possesses HDAC activity to repress transcription. HDAC7 12q13.11 32 92.38 HDAC promoting repression mediated via the transcriptional corepressor SMRT. HDAC8 Xq13.1 16 41.76 Class I of the HDAC family, catalyzing the deacetylation of lysine residues in the histone N‑terminal tails, repressing transcription in large multiprotein complexes with transcriptional corepressors. HDAC9 7p21.1 38 111.33 HDAC family, repressing MEF2 activity through recruitment of multicomponent corepressor complexes that include CtBP and HDACs. This encoded protein may have a role in hematopoiesis. HDAC10 22q13.33 20 71.46 HDAC family, deacetylating lysine residues on the N‑terminal part of the core histones. HDAC11 3p25.1 14 39.19 Class IV HDAC, localized to the nucleus and may be involved in regulating the expression of interleukin 10. SIRT1 10q21.3 11 47.06 Class I of the sirtuin family. May function as intracellular regulatory proteins with mono‑ADP‑ribosyltransferase activity. SIRT2 19q13.2 17 39.52 Class I of the sirtuin family. May function as intracellular regulatory proteins with mono‑ADP‑ribosyltransferase activity. SIRT3 11p15.5 9 43.58 Class I of the sirtuin family. May function as intracellular regulatory proteins with mono‑ADP‑ribosyltransferase activity. SIRT4 12q24.23‑q24.31 5 35.19 Class IV of the sirtuin family. May function as intracellular regulatory proteins with mono‑ADP‑ribosyltransferase activity. SIRT5 6p23 15 33.89 Class III of the sirtuin family. May function as intracellular regulatory proteins with mono‑ADP‑ribosyltransferase activity. SIRT6 19p13.3 9 36.44 A member of the sirtuin family of NAD‑dependent enzymes that are implicated in cellular stress resistance, genomic stability, aging and energy homeostasis. Localized to the nucleus and exhibits ADP‑ribosyl transferase and HDAC activities. Participates in DNA repair, maintenance of telomeric chromatin, inflammation, as well as in lipid and glucose metabolism. SIRT7 17q25.3 11 44.9 Class IV of the sirtuin family. May function as intracellular regulatory proteins with mono‑ADP‑ribosyltransferase activity. Table SI. Continued. B, HATs and associated genes Protein Gene Location Exon mass (kDa) Encoding protein and biological function HAT1 2q31.1 12 49.52 A type B HAT that is involved in the rapid acetylation of newly synthesized cytoplasmic histones, which are in turn imported into the nucleus for de novo deposition onto nascent DNA chains. Histone acetylation, particularly of histone H4, has an important role in replication‑dependent chromatin assembly. Specifically, this HAT may acetylate soluble but not nucleosomal histone H4 at lysines 5 and 12, and to a lesser degree, histone H2A at lysine 5. KAT2A 17q21.2 18 93.94 Also known as GCN5. A HAT that functions primarily as a transcriptional activator. It also functions as a repressor of NF‑κB by promoting ubiquitination of the NF‑κB subunit RELA in a HAT‑independent manner. KAT2B 3p24.3 19 93.03 Possesses HAT activity. Associates with p300/CBP by binding to numerous sequence‑specific factors, including c‑jun or the adenoviral oncoprotein E1A, involved in cell growth and/or differentiation. Has a direct role in transcriptional regulation. KAT5 11q13.1 13 53.08 The MYST family of HATs, regulating chromatin remodeling, transcription and other nuclear processes by acetylating histone and nonhistone proteins. Participation in DNA repair and apoptosis. Important role in signal transduction. CREBBP 16p13.3 33 265.44 Transcriptional coactivation. Binding to CREB, this HAT acts as a scaffold to stabilize additional protein interactions with the transcription complex. Very high sequence similarity with protein p300 in its bromodomain, cysteine‑histidine‑rich regions, and HAT domain. Mutations in this gene cause RTS. Chromosomal translocations involving this gene have been associated with acute myeloid leukemia. EP300 22q13.2 31 264.25 Encodes the adenovirus E1A‑associated cellular p300 transcriptional co‑activator protein. A HAT regulating transcription via chromatin remodeling, mediating cAMP gene regulation by binding specifically to phosphorylated CREB protein. A co‑activator of hypoxia‑inducible factor 1 alpha, thus stimulating hypoxia‑induced genes such as VEGF. Defects in this gene are a cause of RTS and may also have a role in epithelial cancer. TAF1 Xq13.1 45 20.89 Coordinating initiation of transcription by RNA polymerase II. The basal transcription factor TFIID, binding to core promoter sequences encompassing the transcription start site and also binding to activators and other transcriptional regulators. Contain two independent protein kinase domains at the N‑ and C‑terminals, but also possess acetyltransferase activity and may act as a ubiquitin‑activating/conjugating enzyme. Mutations in this gene result in Dystonia 3, torsion, X‑linked, a dystonia‑parkinsonism disorder. ELP3 8p21.1 18 The catalytic subunit of the HAT elongator complex, which contributes to transcript elongation and also regulates the maturation of projection neurons. NCOA1 2p23.3 24 156.8 A transcriptional coactivator for steroid and nuclear hormone receptors. A member of the p160/steroid receptor coactivator family, which has HAT activity and contains a nuclear localization signal, as well as bHLH and PAS domains. Also binds nuclear receptors directly and stimulates the transcriptional activities in a hormone‑dependent manner. NCOA2 8q13.3 32 159.2 A transcriptional coactivator for nuclear hormone receptors, including steroid, thyroid, retinoid and vitamin D receptors. Also an intermediary factor for the ligand‑dependent activity of these nuclear receptors, which regulate their target genes upon binding of cognate response elements. NCOA3 20q13.12 23 154.81 A nuclear receptor coactivator that interacts with nuclear hormone receptors to enhance their transcriptional activator functions. A HAT recruiting p300/CBP‑associated factor and CREB binding protein as part of a multisubunit coactivation complex. Table SI. Continued. B, HATs and associated genes Protein Gene Location Exon mass (kDa) Encoding protein and biological function CLOCK 4q12 28 Participates in the regulation of circadian rhythms. A transcription factor of the bHLH family that possesses DNA‑binding and HAT activity. Forms a heterodimer with ARNTL (BMAL1) that binds E‑box enhancer elements upstream of period circadian regulator 1, 2 and 3 and cryptochrome 1 and 2 genes, and activates transcription of these genes. Polymorphisms in this gene may be associated with behavioral changes in certain populations and with obesity and metabolic syndrome. C, HMT‑encoding and associated genes Protein Gene Location Exon mass (kDa) Encoding protein and biological function SMYD1 2p11.2 10 56.63 ‑ SMYD2 1q32.3 12 49.77 SET domain‑containing proteins, including SMYD2, catalyze lysine methylation. SMYD3 1q44 30 ‑ A HMT that functions in RNA polymerase II complexes by interaction with a specific RNA helicase. SMYD4 17p13.3 14 89.18 ‑ SMYD5 2p13.2 13 34.42 ‑ PRMT1 19q13.33 13 39.61 Table SI. Continued. C, HMT‑encoding and associated genes Protein Gene Location Exon mass (kDa) Encoding protein and biological function NSD1 5q35.3 31 267.39 Containing a SET domain, 2 LXXLL motifs, 3 nuclear translocation signals, 4 PHD finger regions, and a proline‑rich region. Enhances androgen receptor transactivation. Acts as a nucleus‑localized,