title: The role of plasma cell-free DNA detection in predicting preoperative chemoradiotherapy response in rectal cancer patients.
abstract: In the present study, we studied the relationship between plasma cell-free DNA and the effect of preoperative chemoradiotherapy in patients with rectal cancer. The concentration, KRAS mutation and O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status of cell-free DNA were measured by using polymerase chain reaction (PCR) analyses. The response to chemoradiotherapy was assessed using tumor regression grading (TRG) scores. The cell-free DNA concentrations in patients with rectal cancer (n=34) were significantly higher compared to healthy controls (n=10). The 400-base pair (bp) DNA concentration, 400-/100-bp DNA ratio decreased significantly after chemoradiotherapy in the good response group. The incidence of KRAS mutation decreased significantly after chemoradiotherapy in both good and poor response groups. Higher MGMT promoter methylation status at baseline DNA was associated with a better tumor response. Therefore, cell-free DNA detection may be useful in evaluating the effect of preoperative chemoradiotherapy in patients with rectal cancer.
authors.affiliation: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China.
authors.forename: W
authors.initials: W
authors.lastname: Sun
authors.affiliation: Cancer Research Institute of Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China.
authors.forename: Y
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Cancer Research Institute of Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China.
authors.forename: M
authors.initials: M
authors.lastname: Zhu
authors.affiliation: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China.
authors.forename: Z
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China.
authors.forename: H
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Cancer Research Institute of Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China.
authors.forename: Y
authors.initials: Y
authors.lastname: Xin
authors.affiliation: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China.
authors.forename: G
authors.initials: G
authors.lastname: Jiang
authors.affiliation: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China.
authors.forename: X
authors.initials: X
authors.lastname: Guo
authors.affiliation: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China.
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China.
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D016022:Case-Control Studies; D059186:Chemoradiotherapy, Adjuvant; D004247:DNA / Q000097:blood*; D019175:DNA Methylation; D015254:DNA Modification Methylases / Q000235:genetics; D004252:DNA Mutational Analysis; D045643:DNA Repair Enzymes / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011401:Promoter Regions, Genetic; D011518:Proto-Oncogene Proteins / Q000235:genetics; D016283:Proto-Oncogene Proteins p21(ras); D012004:Rectal Neoplasms / Q000097:blood* / Q000235:genetics / Q000628:therapy; D016896:Treatment Outcome; D025521:Tumor Suppressor Proteins / Q000235:genetics; D055815:Young Adult; D018631:ras Proteins / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D025521:Tumor Suppressor Proteins; D004247:DNA; D015254:DNA Modification Methylases; C515491:MGMT protein, human; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins; D045643:DNA Repair Enzymes