{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T05:19:29Z","timestamp":1790659169103,"version":"4.1.0"},"reference-count":42,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,5,20]],"date-time":"2023-05-20T00:00:00Z","timestamp":1684540800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Plan for Science, Technology, and Innovation (MAARIFAH), King Abdulaziz City for Science and Technology","award":["2-17-01-001-0069"],"award-info":[{"award-number":["2-17-01-001-0069"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Colon cancer (CC) has a high mortality rate and is often diagnosed at an advanced stage in Saudi Arabia. Thus, the identification and characterization of potential new cancer-specific biomarkers are imperative for improving the diagnosis of CC by detecting it at an early stage. Cancer-testis (CT) genes have been identified as potential biomarkers for the early diagnosis of various cancers. Among the CT genes are those belonging to the SSX family. In order to assess the usefulness of SSX family genes as cancer biomarkers for the detection of early-stage CC, the goal of this research was to validate the expressions of these genes in patients with CC and in matched patients with normal colons (NCs). Materials and Methods: RT-PCR assays were used to analyze the SSX1, SSX2, and SSX3 family gene expression levels in 30 neighboring NC and CC tissue samples from male Saudi patients. Epigenetic alterations were also tested in vitro using qRT-PCR analysis to determine whether reduced DNA methyltransferase or histone deacetylation could stimulate SSX gene expression via 5-aza-2\u2032-deoxycytidine and trichostatin treatments, respectively. Results: The RT-PCR results showed SSX1 and SSX2 gene expression in 10% and 20% of the CC tissue specimens, respectively, but not in any of the NC tissue specimens. However, no SSX3 expression was detected in any of the examined CC or NC tissue samples. In addition, the qRT-PCR results showed significantly higher SSX1 and SSX2 expression levels in the CC tissue samples than in the NC tissue samples. The 5-aza-2\u2032-deoxycytidine and trichostatin treatments significantly induced the mRNA expression levels of the SSX1, SSX2, and SSX3 genes in the CC cells in vitro. Conclusions: These findings suggest that SSX1 and SSX2 are potentially suitable candidate biomarkers for CC. Their expressions can be regulated via hypomethylating and histone deacetylase treatments, subsequently providing a potential therapeutic target for CC.<\/jats:p>","DOI":"10.3390\/medicina59050988","type":"journal-article","created":{"date-parts":[[2023,5,22]],"date-time":"2023-05-22T03:57:32Z","timestamp":1684727852000},"page":"988","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Higher Expression Levels of SSX1 and SSX2 in Patients with Colon Cancer: Regulated In Vitro by the Inhibition of Methylation and Histone Deacetylation"],"prefix":"10.3390","volume":"59","author":[{"given":"Turki M.","family":"Alrubie","sequence":"first","affiliation":[{"name":"Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdullah M.","family":"Alamri","sequence":"additional","affiliation":[{"name":"Genome Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh 11495, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4697-5204","authenticated-orcid":false,"given":"Bader O.","family":"Almutairi","sequence":"additional","affiliation":[{"name":"Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3761-6656","authenticated-orcid":false,"given":"Abdulwahed F.","family":"Alrefaei","sequence":"additional","affiliation":[{"name":"Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maha M.","family":"Arafah","sequence":"additional","affiliation":[{"name":"Pathology Department, College of Medicine, King Saud University, Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammad","family":"Alanazi","sequence":"additional","affiliation":[{"name":"Genome Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh 11495, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5797-8304","authenticated-orcid":false,"given":"Abdelhabib","family":"Semlali","sequence":"additional","affiliation":[{"name":"Groupe de Recherche en \u00c9cologie Buccale, Facult\u00e9 de M\u00e9decine Dentaire, Universit\u00e9 Laval, 2420 Rue de la Terrasse, Local 1758, Qu\u00e9bec, QC G1V 0A6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0337-6412","authenticated-orcid":false,"given":"Mikhlid H.","family":"Almutairi","sequence":"additional","affiliation":[{"name":"Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2992","DOI":"10.1002\/ijc.32055","article-title":"Global trends in colorectal cancer mortality: Projections to the year 2035","volume":"144","author":"Araghi","year":"2019","journal-title":"Int. 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