KRAS mutation detection and prognostic potential in sporadic colorectal cancer using high-resolution melting analysis.
BACKGROUND
The development of targeted therapies has created a pressing clinical need for molecular characterisation of cancers. In this retrospective study, high-resolution melting analysis (HRMA) was validated and implemented for screening of 164 colorectal cancer (CRC) patients to detect KRAS hot-spot mutations and to evaluate its prognostic value. Direct sequencing was used to confirm and characterise HRMA results.


METHODS
After establishing its sensitivity, HRMA was validated on seven cell lines and inter- and intra-variation were analysed. The prognostic value of KRAS mutations in CRC was evaluated using survival analysis.


RESULTS
HRMA revealed abnormal melting patterns in 34.1% CRC samples. Kaplan-Meier survival curves revealed a significantly shorter overall (OS) and disease-free survival (DFS) for CRC patients harbouring a KRAS mutation. In the Cox regression analysis, only when colon and rectal cancer were analysed separately, KRAS mutation was a negative predictor for OS in patients with rectal cancer and DFS in those with stage II colon cancer.


CONCLUSIONS
HRMA was found to be a valid screening method for KRAS mutation detection. The KRAS mutation came forward as a negative predictive factor for OS in patients with rectal cancer and for DFS in stage II colon cancer patients.
Deschoolmeester
V
V
Laboratory of Cancer Research and Clinical Oncology, Department of Medical Oncology, University of Antwerp/Antwerp University Hospital, Wilrijk 2610, Belgium. vanessa.deschoolmeester@ua.ac.be
Boeckx
C
C
Baay
M
M
Weyler
J
J
Wuyts
W
W
Van Marck
E
E
Peeters
M
M
Lardon
F
F
Vermorken
J B
JB
D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000235:genetics / Q000401:mortality / Q000473:pathology; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology / Q000517:prevention & control; D017931:DNA Primers; D004273:DNA, Neoplasm / Q000235:genetics; D014644:Genetic Variation; D006801:Humans; D008403:Mass Screening / Q000379:methods; D009154:Mutation; D009691:Nucleic Acid Denaturation; D016133:Polymerase Chain Reaction; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D012004:Rectal Neoplasms / Q000235:genetics / Q000401:mortality / Q000473:pathology; D012044:Regression Analysis; D016019:Survival Analysis; D018631:ras Proteins / Q000235:genetics*
D017931:DNA Primers; D004273:DNA, Neoplasm; C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins