title: High-resolution melting assay (HRMA) is a simple and sensitive stool-based DNA Test for the detection of mutations in colorectal neoplasms.
abstract: BACKGROUND
  Stool-based DNA testing for colorectal cancer is becoming a favored alternative to existing DNA screening tests. However, current methods of analysis often become more complicated and costly with increased sensitivity. The high-resolution melting assay (HRMA) is a simple and rapid mutation scanning method with low cost and superb accuracy. In this study, we verified the accuracy of HRMA for screening KRAS/TP53 mutations in stool-isolated DNA from patients with colorectal cancer.
  
  
  METHODS
  Comparing to direct DNA sequencing, the accuracy of HRMA was verified by detecting KRAS/TP53 mutations in 2 independent stages. In study stage I, both tissue and stool samples from colorectal neoplasm patients were analyzed. In study stage II, stool samples from patients with colorectal neoplasms, and normal controls in clinical screening settings were examined.
  
  
  RESULTS
  In study stage I, the HRMA identified 14 of 17 target mutations (82.4%) in stools from cancer patients, and 4 of 5 (80.0%) target mutations in stools from advanced adenoma patients. The mutation detection rate in fecal samples (45.0%; 18/40) and referred tissue samples (55.0%; 22/40) was highly consistent (κ = 0.79). The HRMA detected 1% mutant DNA in a background of wild type DNA. In study stage II, the HRMA assay detected 58.8% (20/34) mutations in tumor samples, 41.5% (17/41) in advanced adenomas samples, and 3.33% (2/60) in age-matched normal control samples. The results from HRMA and DNA sequencing revealed 100% sensitivity and specificity in both tissue and stool samples.
  
  
  CONCLUSIONS
  HRMA is a simple, reliable, and sensitive method for detecting DNA mutations in the stool samples from patients with colorectal neoplasms.
authors.affiliation: Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Bing-Sheng
authors.initials: BS
authors.lastname: Li
authors.forename: Xin-Ying
authors.initials: XY
authors.lastname: Wang
authors.forename: An-Gao
authors.initials: AG
authors.lastname: Xu
authors.forename: Feng-Li
authors.initials: FL
authors.lastname: Ma
authors.forename: Qun-Ying
authors.initials: QY
authors.lastname: Ma
authors.forename: Zao
authors.initials: Z
authors.lastname: Li
authors.forename: Ji-Hong
authors.initials: JH
authors.lastname: Liu
authors.forename: Ai-Hua
authors.initials: AH
authors.lastname: Gan
authors.forename: Zhi-Jin
authors.initials: ZJ
authors.lastname: Yu
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Jiang
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000235:genetics; D002288:Adenocarcinoma, Mucinous / Q000175:diagnosis* / Q000235:genetics; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000235:genetics; D004247:DNA / Q000235:genetics*; D005243:Feces / Q000737:chemistry*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics; D016283:Proto-Oncogene Proteins p21(ras); D012680:Sensitivity and Specificity; D044366:Transition Temperature; D016159:Tumor Suppressor Protein p53 / Q000235:genetics; D018631:ras Proteins / Q000235:genetics
chemical_list: C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D004247:DNA; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins