title: Polymorphisms of tumor necrosis factor alpha in Middle Eastern population with colorectal cancer.
abstract: Tumor necrosis factor-alpha (TNF-α) contributes in inflammation and has been implicated in the development of colorectal cancer (CRC). Single nucleotide polymorphisms (SNPs) in TNF-α promoter could affect the risk of CRC by regulating TNF-α production. This is the first study to investigate TNF-α SNPs in a Middle Eastern population. In this study, we examined three SNPs in TNF-α for association with CRC. One hundred CRC patients and 100 controls were genotyped for TNF-α -308, -238, and -857 using TaqMan allelic discrimination assay. The TNF-α -238 (G/A) genotype was significantly associated with high risk of CRC (p = 0.003552). The distribution of three genotypes of -238 G/A was significantly different between the controls and CRC patients even after Bonferroni's correction. The AA genotype of -238 G/A SNP was observed at considerably higher proportion (13 %) in CRCs compared to controls (1 %). Additionally, similar to genotypes, the allelic frequencies of -238 G/A were significantly different between the CRC cases and controls (odds ratios (OR) = 7.647, χ (2) = 18.50, p = 0.00002). The genotype frequencies of -308 and -857 were not notably different between the cases and controls. TNF-α -238A may be useful as a screening marker to identify individuals prior to their acquiring CRC in the Saudi population although, further validations in larger cohorts are needed.
authors.affiliation: Colorectal Research Chair, Department of Surgery, College of Medicine, King Khalid University Hospital, King Saud University, P.O. Box 7805 (37), Riyadh, 11472, Saudi Arabia. mabdulla@ksu.edu.sa.
authors.forename: Maha-Abdulla
authors.initials: MA
authors.lastname: Hamadien
authors.affiliation: Genomic Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Zahid
authors.initials: Z
authors.lastname: Khan
authors.affiliation: Colorectal Research Chair, Department of Surgery, College of Medicine, King Khalid University Hospital, King Saud University, P.O. Box 7805 (37), Riyadh, 11472, Saudi Arabia.
authors.forename: Mansoor-Ali
authors.initials: MA
authors.lastname: Vaali-Mohammed
authors.affiliation: Colorectal Research Chair, Department of Surgery, College of Medicine, King Khalid University Hospital, King Saud University, P.O. Box 7805 (37), Riyadh, 11472, Saudi Arabia.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Zubaidi
authors.affiliation: Colorectal Research Chair, Department of Surgery, College of Medicine, King Khalid University Hospital, King Saud University, P.O. Box 7805 (37), Riyadh, 11472, Saudi Arabia.
authors.forename: Khayal
authors.initials: K
authors.lastname: Al-Khayal
authors.affiliation: Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, La Jolla, CA, USA.
authors.forename: James
authors.initials: J
authors.lastname: McKerrow
authors.affiliation: Colorectal Research Chair, Department of Surgery, College of Medicine, King Khalid University Hospital, King Saud University, P.O. Box 7805 (37), Riyadh, 11472, Saudi Arabia.
authors.forename: Omar
authors.initials: O
authors.lastname: Al-Obeed
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000235:genetics* / Q000473:pathology; D005260:Female; D020022:Genetic Predisposition to Disease; D005828:Genetics, Population; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D012307:Risk Factors; D012529:Saudi Arabia; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
chemical_list: D014409:Tumor Necrosis Factor-alpha
keywords: Colorectal cancer; Polymorphisms; Tumor necrosis factor