title: [Microsatellite analysis and hMLH1/hMSH2 expression detection in young patients with colorectal cancer: value in screening hereditary nonpolyposis colorectal cancer].
abstract: OBJECTIVE
  To evaluate the frequency of microsatellite instability (MSI) and absence of hMLH1/hMSH2 expression in young patients with colorectal cancer, and investigate their role in screening hereditary nonpolyposis colorectal cancer (HNPCC).
  
  
  METHODS
  Seventy-three young patients (below 40 years old) with colorectal cancer were examined for DNA mismatch repair deficiency by microsatellite testing and immunohistochemical detection of hMLH1/hMSH2 gene products.
  
  
  RESULTS
  The frequency of MSI and absence rate of hMLH1/hMSH2 expression are 56.16% and 49.32% in these patients, respectively, which increased significantly with younger age for cancer diagnosis.
  
  
  CONCLUSIONS
  Defects in the DNA mismatch repair system are frequent in Chinese young patients with colorectal cancer. Microsatellite analysis and immunohistochemical detection are useful for efficient identification of HNPCC in these young patients.
authors.affiliation: Department of Pathology, Southern Medical University, Guangzhou, China. yanglei@fimmu.com
authors.forename: Lei
authors.initials: L
authors.lastname: Yang
authors.forename: Yan-qing
authors.initials: YQ
authors.lastname: Ding
authors.forename: Guo-xin
authors.initials: GX
authors.lastname: Li
authors.forename: Jiang
authors.initials: J
authors.lastname: Yu
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.forename: Hong-jun
authors.initials: HJ
authors.lastname: Yang
authors.forename: Jin-hua
authors.initials: JH
authors.lastname: Zhang
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000096:biosynthesis*; D000293:Adolescent; D000328:Adult; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008403:Mass Screening; D053842:Microsatellite Instability; D018895:Microsatellite Repeats / Q000235:genetics*; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein / Q000096:biosynthesis*; D009687:Nuclear Proteins / Q000096:biosynthesis*; D055815:Young Adult
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C501486:MLH1 protein, human; D009687:Nuclear Proteins; C497172:MSH2 protein, human; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein