Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Prostaglandin H synthase 2 (also known as cyclooxygenase-2) is thought to play a role in the prevention of colon cancer by aspirin, an inhibitor of the enzyme. We used DNA heteroduplex analysis to screen the prostaglandin H synthase 2 gene, to search for naturally occurring enzyme variants that may simulate the effects of aspirin. We found among African-Americans a single-nucleotide polymorphism that changes valine to alanine at residue 511 (V511A; GTT>GCT; g.5939T>C; allele frequency 0.045). The polymorphism was also seen among Asian-Indians (allele frequency, 0.03) but not among Chinese, Filipinos, Hispanics, Japanese, Koreans, Samoans, and Caucasians. The amino acid change is predicted to open a 53 cubic angstrom cavity near the active site of the enzyme, but no change in V(max), K(m), or thermal stability was observed for the variant enzyme in COS-1 cell transfection assays. Case-control analysis of African-Americans from two different study populations showed a 0.56 odds ratio for colorectal adenomas among polymorphism carriers (95% confidence interval, 0.25-1.27; 161 cases and 219 controls). A similar analysis of African-Americans nested in the Multiethnic Cohort Study showed a 0.67 odds ratio for colorectal cancer (95% confidence interval, 0.28-1.56; 138 cases and 258 controls). Consistency of the results across all three of the studies is potentially compatible with a protective effect of the polymorphism, mimicking aspirin.
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PMID:Prostaglandin H synthase 2 variant (Val511Ala) in African Americans may reduce the risk for colorectal neoplasia. 1243 7

Laparoscopic complete mesocolic excision is gradually becoming the standard surgical approach in colon cancer therapy, the core element of which is central vascular ligation. However, this increases the difficulty for surgeons, particularly in the context of right colectomy, which encounters complex vascular anatomy. This study aimed to examine vascular variations that occur during laparoscopic right hemicolectomy through a review of the medical literature. We demonstrated that the ICA and MCA are evident in the majority of patients. The RCA was inconsistently present ranging from 12% to 45%. The ICA passed the SMV anteriorly or posteriorly at average rates. However, the RCA passed anterior to the SMV in most patients. Regarding intravenous, the ICV was consistently present, whereas the RCV was absent in up to 80% of patients. The GTH was present in nearly 80% of patients. We classified the vascular variations by the location of the branches instead of using numerical classification. The GCT and GPCT were common types whilst the GPT was relatively rare. In summary, detailed information on the vascular anatomical variations occurring on the right-side of the colon is vital. Failure to identify variations during surgical procedures can result in unwanted bleeding. Thus, we advocate for the use of the ICV as an anatomic marker during surgery.
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PMID:Vascular anatomical variation in laparoscopic right hemicolectomy. 3097 67