title: Loss of heterozygosity and microsatellite instability as predictive markers among Iranian esophageal cancer patients.
abstract: OBJECTIVE
  Variation in microsatellite sequences that are dispersed in the genome has been linked to a deficiency in cellular mismatch repair system and defects in several genes of this system are involved in carcinogenesis. Our aim in this study was to illustrate microsatellite DNA alteration in esophageal cancer.
  
  
  METHODS
  DNA was extracted from formalin fixed paraffin embedded (FFPE) tissues from surgical and matched margin-normal samples. Microsatellite instability (MSI) and loss of heterozygosity (LOH) were studied in 50 cases of esophageal squamous cell carcinoma (ESCC) by amplifying six microsatellite markers: D13S260 (13q12.3), D13S267 (13q12.3), D9S171 (9p21), D2S123 (2p), D5S2501 (5q21) and TP53 (17p13.1) analyzed on 6% denaturing polyacrylamide gel electrophoresis.
  
  
  RESULTS
  Statistical analysis indicated a near significant reverse correlation between grade and LOH (P= 0.068, correlation coefficient= -0.272). Specifically, increased LOH in tumor DNA has a significant correlation with increased differentiation from poorly differentiated to well differentiated tumors (P= 0.002 and P= 0.016 respectively). In addition, higher number of chromosomal loci with LOH showed a reverse correlation with lymph node metastasis (P= 0.026, correlation coefficient= -0.485). Furthermore, there was a positive correlation between addiction and MSI (P= 0.026, correlation coefficient= 0.465).
  
  
  CONCLUSIONS
  Microsatellite DNA alterations may be a prognostic tool for detection and the evolution of prognosis in patients with SCC of esophagus. It can be concluded that regional lymph node metastasis would be less likely with increased heterozygote loci and addiction with any of opium, cigarette, water pipe or alcohol can be a susceptibility factor(s) for MSI.
authors.affiliation: Cellular and Molecular Research Center, Sabzevar University of Medical Sciences, Sabzevar, Iran.
authors.forename: Mohammad Mahdi
authors.initials: MM
authors.lastname: Forghanifard
authors.affiliation: Division of Human Genetics, Immunology Research Center, Avicenna Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Elham Emami
authors.initials: EE
authors.lastname: Vahid
authors.affiliation: School of Systems Biology, George Mason University, Manassas, Virginia, U.S.A.
authors.forename: Ezzat
authors.initials: E
authors.lastname: Dadkhah
authors.affiliation: Division of Human Genetics, Immunology Research Center, Avicenna Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mehran
authors.initials: M
authors.lastname: Gholamin
authors.affiliation: Department of hematopathology, Central Laboratory, Imam Reza Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Samaneh Broumand
authors.initials: SB
authors.lastname: Noghabi
authors.affiliation: Division of Human Genetics, Immunology Research Center, Avicenna Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Martha
authors.initials: M
authors.lastname: Ghahraman
authors.affiliation: Cancer Molecular Pathology Research Center, Imam Reza Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Farzadnia
authors.affiliation: Division of Human Genetics, Immunology Research Center, Avicenna Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Medical Genetics Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Abbaszadegan
keywords: Esophageal squamous cell -carcinoma; Loss of heterozygosity; Microsatellite instability