title: Immunohistochemical analysis of mismatch repair proteins in Iranian colorectal cancer patients at risk for lynch syndrome.
abstract: BACKGROUND
  Hereditary non-polyposis colorectal cancer (HNPCC) is a common hereditary cancer predisposing syndrome has molecular and clinicopathological features still have remained ambiguous within Iranian populations. We discuss in this article some molecular and clinicopathological features of the condition.
  
  
  METHODS
  The study was a descriptive retrospective and designed on 1659 colorectal cancer (CRC) patients were screened based on early-onset disease and Amsterdam II criteria during 14 years (2000-2013). Immunohistochemistry (IHC) staining was set up to detect expression of mismatch repair (MMR) genes on paraffin-embedded tissue sections of 31 HNPCC-CRC tumors. SPSS 19 software was used to analyze the data.
  
  
  RESULTS
  IHC-MMR staining was absent in 7/31 individuals (22.6%) of which 4 cases showed IHC-Absent (IHC-A) in both MSH2 and MSH6 (57.1%), in 2 cases both MLH1 and PMS2 had negative staining (28.6%), and just in one case, MSH6 was defective (14.3%). The frequency of CRC among IHC-A and IHC-Present (IHC-P) families was 67.5% and 27.9%, respectively. Also the most frequent extracolonic cancers in IHC-A group were: stomach (10%), small bowel (5%), and prostate (5%); and in IHC-P group: stomach (18.4%), lung (10.9%), and breast (7.5%). Average age of IHC-A individuals at diagnosis was 38.0 versus 45.3 years in IHC-P individuals. Overall, 20.8% and 57.1% of our index CRCs were localized proximal to the splenic flexure in IHC-P and IHC-A groups, respectively.
  
  
  CONCLUSIONS
  Given the lack of enough information about molecular aspects of hereditary cancer syndromes like HNPCC in Iran, more evaluations are necessary on larger samples using complementary techniques such as MSI-testing and mutation analyses.
authors.affiliation: Cellular and Molecular Research Center, Shahrekord University of Medical Sciences, Shahrekord, Iran ; Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Zeinalian
authors.affiliation: Isfahan University of Medical Sciences, Isfahan, Iran ; Poursina Hakim Research Center, Isfahan, Iran.
authors.forename: Mohammad Hassan
authors.initials: MH
authors.lastname: Emami
authors.affiliation: Isfahan University of Medical Sciences, Isfahan, Iran ; Poursina Hakim Research Center, Isfahan, Iran.
authors.forename: Azar
authors.initials: A
authors.lastname: Naimi
authors.affiliation: Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Rasoul
authors.initials: R
authors.lastname: Salehi
authors.affiliation: Cellular and Molecular Research Center, Shahrekord University of Medical Sciences, Shahrekord, Iran.
authors.forename: Morteza
authors.initials: M
authors.lastname: Hashemzadeh-Chaleshtori
keywords: Immunohistochemistry; Iran; Lynch syndrome; mismatch repair
references.citation: Eur J Hum Genet. 2008 Dec;16(12):1477-86
references.pmid: 18628789
references.citation: Am J Gastroenterol. 2011 Oct;106(10 ):1829-36
references.pmid: 21769135
references.citation: Pathology. 2002 Dec;34(6):541-7
references.pmid: 12555992
references.citation: JAMA. 2006 Sep 27;296(12):1521-3
references.pmid: 17003401
references.citation: J Mol Diagn. 2008 Jul;10(4):293-300
references.pmid: 18556767
references.citation: Cancer Res. 1998 Nov 15;58(22):5248-57
references.pmid: 9823339
references.citation: Cancer Metastasis Rev. 2004 Jan-Jun;23(1-2):11-27
references.pmid: 15000146
references.citation: Cancer. 2002 Dec 1;95(11):2422-30
references.pmid: 12436451
references.citation: Gut. 1995 Mar;36(3):385-90
references.pmid: 7698698
references.citation: Virchows Arch. 2004 Nov;445(5):431-41
references.pmid: 15455227
references.citation: Int J Colorectal Dis. 2013 Sep;28(9):1195-201
references.pmid: 23588873
references.citation: J Natl Cancer Inst. 2007 Feb 21;99(4):261-3
references.pmid: 17312298
references.citation: J Natl Cancer Inst. 2004 Feb 18;96(4):261-8
references.pmid: 14970275
references.citation: Crit Rev Oncog. 2006 Dec;12(3-4):273-87
references.pmid: 17425506
references.citation: Am J Surg Pathol. 1999 Oct;23 (10 ):1248-55
references.pmid: 10524526
references.citation: Adv Anat Pathol. 2009 Nov;16(6):405-17
references.pmid: 19851131
references.citation: Ann Oncol. 2009 Mar;20(3):556-63
references.pmid: 19073863
references.citation: Gut. 2005 Dec;54(12 ):1733-40
references.pmid: 15955785
references.citation: Gastroenterology. 2011 Jan;140(1):73-81
references.pmid: 20727894
references.citation: Clin Cancer Res. 2007 Jul 1;13(13):3831-9
references.pmid: 17606714
references.citation: J Clin Oncol. 2005 Sep 20;23 (27):6524-32
references.pmid: 16116158
references.citation: Clin Genet. 2009 Jul;76(1):1-18
references.pmid: 19659756
references.citation: Asian Pac J Cancer Prev. 2010;11(4):1033-5
references.pmid: 21133620
references.citation: Gastroenterology. 2010 Jun;138(6):2044-58
references.pmid: 20420945
references.citation: Gut. 2008 Nov;57(11):1539-44
references.pmid: 18625694
references.citation: Genomics. 1995 Nov 20;30(2):195-206
references.pmid: 8586419
references.citation: J Med Genet. 1999 Nov;36(11):801-18
references.pmid: 10544223
references.citation: Eur J Cancer. 2000 Jan;36(1):49-54
references.pmid: 10741294
references.citation: J Clin Oncol. 2002 Feb 15;20(4):1043-8
references.pmid: 11844828
references.citation: JAMA. 2005 Apr 27;293(16):1979-85
references.pmid: 15855431
references.citation: J Mol Diagn. 2009 Jul;11(4):266-78
references.pmid: 19541921
references.citation: Int J Cancer. 2008 Jul 15;123(2):444-9
references.pmid: 18398828