Carbohydrate antigen 19-9 (CA19-9), also known as sialyl-LewisA, is a tetrasaccharide which is usually attached to O-glycans on the surface of cells. It is known to play a role in cell-to-cell recognition processes. It is also a tumor marker used primarily in the management of pancreatic cancer.[1]
CA19-9 is the sialylated form of Lewis AntigenA. It is a tetrasaccharide with the sequence Neu5Acα2-3Galβ1-3[Fucα1-4]GlcNAcβ.
Clinical significanceedit
Tumor markeredit
Guidelines from the American Society of Clinical Oncology discourage the use of CA19-9 as a screening test for cancer, particularly pancreatic cancer. The reason is that the test may be falsely normal (false negative) in many cases, or abnormally elevated in people who have no cancer at all (false positive). The main use of CA19-9 is therefore to see whether a pancreatic tumor is secreting it; if that is the case, then the levels should fall when the tumor is treated, and they may rise again if the disease recurs.[2] Therefore it is useful as a surrogate marker for relapse.
In people with pancreatic masses, CA19-9 can be useful in distinguishing between cancer and other diseases of the gland.[1][3]
In patients who lack the Lewis antigen A (a blood type antigen on red blood cells), which is about 10% of the Caucasian population, CA19-9 is not produced by any cells,[3] even in those with large tumors.[2] This is because of a deficiency of a fucosyltransferase enzyme that is needed to produce Lewis antigen A.[2]
Historyedit
CA19-9 was discovered in the serum of patients with colon cancer and pancreatic cancer in 1981.[4] It was characterized shortly after, and it was found to be carried primarily by mucins.[5]
^ abcdePerkins, G.; Slater, E.; Sanders, G.; Prichard, J. (2003). "Serum tumor markers". American Family Physician. 68 (6): 1075–1082. PMID 14524394.
^ abcLocker G, Hamilton S, Harris J, Jessup J, Kemeny N, Macdonald J, Somerfield M, Hayes D, Bast R (2006). "ASCO 2006 update of recommendations for the use of tumor markers in gastrointestinal cancer". J. Clin. Oncol. 24 (33): 5313–27. doi:10.1200/JCO.2006.08.2644. PMID 17060676.
^ abcdGoonetilleke KS, Siriwardena AK (April 2007). "Systematic review of carbohydrate antigen (CA19-9) as a biochemical marker in the diagnosis of pancreatic cancer". Eur J Surg Oncol. 33 (3): 266–70. doi:10.1016/j.ejso.2006.10.004. PMID 17097848.
^Koprowski H, Herlyn M, Steplewski Z, Sears HF (1981). "Specific antigen in serum of patients with colon carcinoma". Science. 212 (4490): 53–5. Bibcode:1981Sci...212...53K. doi:10.1126/science.6163212. PMID 6163212.
^Magnani, JL (15 June 2004). "The discovery, biology, and drug development of sialyl Lea and sialyl Lex". Archives of Biochemistry and Biophysics. 426 (2): 122–31. doi:10.1016/j.abb.2004.04.008. PMID 15158662.
CA19-9: analyte monograph - The Association for Clinical Biochemistry and Laboratory Medicine
Essentials of Glycobiology 3rd Edition, Chapter 14: "Structures Common to Different Glycans" https://www.ncbi.nlm.nih.gov/books/NBK453042/#_Ch14_s2_
January 01, 1970
ca19, carbohydrate, antigen, also, known, sialyl, lewisa, tetrasaccharide, which, usually, attached, glycans, surface, cells, known, play, role, cell, cell, recognition, processes, also, tumor, marker, used, primarily, management, pancreatic, cancer, sialyl, l. Carbohydrate antigen 19 9 CA19 9 also known as sialyl LewisA is a tetrasaccharide which is usually attached to O glycans on the surface of cells It is known to play a role in cell to cell recognition processes It is also a tumor marker used primarily in the management of pancreatic cancer 1 Sialyl LewisA Names Systematic IUPAC name 12S 14S 15R 16R 32R 33R 34S 35S 36R 52R 53S 54R 55R 563 72S 73S 74R 75S 76S 15 55 Diacetamido 14 33 35 56 73 74 75 heptahydroxy 36 52 bis hydroxymethyl 76 methyl 16 1R 2R 1 2 3 trihydroxypropyl 2 4 6 trioxa 1 7 2 3 4 2 5 4 3 tetraoxanaheptaphane 12 carboxylic acid Other names sialyl LeA SLeA cancer antigen 19 9 CA19 9 Identifiers CAS Number 92448 22 1 Y 3D model JSmol Interactive image ChEBI CHEBI 61793 ChemSpider 9160877 MeSH sialyl Lewis A PubChem CID 10985677 UNII ZEJ6FM4UJK Y SMILES O C O C 1 O C H 2 C H O C H CO O C H O C H 3 C H O C H 4 C H O C H O C H O C H C O4 C H CO OC O C H 3NC C O C H 2O C C H O C H NC C O C H C H O C H O CO O1 Properties Chemical formula C 31H 52N 2O 23 Molar mass 820 748 g mol 1 Except where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa Y verify what is Y N Infobox references Contents 1 Structure 2 Clinical significance 2 1 Tumor marker 2 1 1 Limitations 3 History 4 See also 5 References 6 External linksStructure editCA19 9 is the sialylated form of Lewis AntigenA It is a tetrasaccharide with the sequence Neu5Aca2 3Galb1 3 Fuca1 4 GlcNAcb Clinical significance editTumor marker edit Guidelines from the American Society of Clinical Oncology discourage the use of CA19 9 as a screening test for cancer particularly pancreatic cancer The reason is that the test may be falsely normal false negative in many cases or abnormally elevated in people who have no cancer at all false positive The main use of CA19 9 is therefore to see whether a pancreatic tumor is secreting it if that is the case then the levels should fall when the tumor is treated and they may rise again if the disease recurs 2 Therefore it is useful as a surrogate marker for relapse In people with pancreatic masses CA19 9 can be useful in distinguishing between cancer and other diseases of the gland 1 3 Limitations edit CA19 9 can be elevated in many types of gastrointestinal cancer such as colorectal cancer esophageal cancer and hepatocellular carcinoma 1 Apart from cancer elevated levels may occur in pancreatitis cirrhosis 1 and diseases of the bile ducts 1 3 It can also be elevated in people with obstruction of the bile ducts 3 In patients who lack the Lewis antigen A a blood type antigen on red blood cells which is about 10 of the Caucasian population CA19 9 is not produced by any cells 3 even in those with large tumors 2 This is because of a deficiency of a fucosyltransferase enzyme that is needed to produce Lewis antigen A 2 History editCA19 9 was discovered in the serum of patients with colon cancer and pancreatic cancer in 1981 4 It was characterized shortly after and it was found to be carried primarily by mucins 5 See also editSialyl Lewis X Lewis antigen systemReferences edit a b c d e Perkins G Slater E Sanders G Prichard J 2003 Serum tumor markers American Family Physician 68 6 1075 1082 PMID 14524394 a b c Locker G Hamilton S Harris J Jessup J Kemeny N Macdonald J Somerfield M Hayes D Bast R 2006 ASCO 2006 update of recommendations for the use of tumor markers in gastrointestinal cancer J Clin Oncol 24 33 5313 27 doi 10 1200 JCO 2006 08 2644 PMID 17060676 a b c d Goonetilleke KS Siriwardena AK April 2007 Systematic review of carbohydrate antigen CA19 9 as a biochemical marker in the diagnosis of pancreatic cancer Eur J Surg Oncol 33 3 266 70 doi 10 1016 j ejso 2006 10 004 PMID 17097848 Koprowski H Herlyn M Steplewski Z Sears HF 1981 Specific antigen in serum of patients with colon carcinoma Science 212 4490 53 5 Bibcode 1981Sci 212 53K doi 10 1126 science 6163212 PMID 6163212 Magnani JL 15 June 2004 The discovery biology and drug development of sialyl Lea and sialyl Lex Archives of Biochemistry and Biophysics 426 2 122 31 doi 10 1016 j abb 2004 04 008 PMID 15158662 External links editCA 19 9 Antigen at the U S National Library of Medicine Medical Subject Headings MeSH CA19 9 at Lab Tests Online CA19 9 analyte monograph The Association for Clinical Biochemistry and Laboratory Medicine Essentials of Glycobiology 3rd Edition Chapter 14 Structures Common to Different Glycans https www ncbi nlm nih gov books NBK453042 Ch14 s2 Retrieved from https en wikipedia org w index php title CA19 9 amp oldid 1152395981, wikipedia, wiki, book, books, library,
