Mutation analysis of the checkpoint kinase 2 gene in colorectal cancer cell lines.
BACKGROUND
Checkpoint kinase 2 (CHK2) is a DNA damage-activated protein kinase which is involved in cell cycle checkpoint control. CHK2 gene could be a candidate gene for colorectal cancer susceptibility. But there are few systematic reports on mutation of CHK2 in colorectal cancer.


METHODS
The mutations of all 14 exons of CHK2 in 56 colorectal cancer cell lines were screened systematically, using denaturing high-performance liquid chromatography (DHPLC) to screen the mismatches of the CHK2 exons amplified products, and then the suspected mutant cell lines were scanned by nucleotide sequence analysis.


RESULTS
VACO400 in CHK2 exon 1a was suspected to have mutation by DHPLC and confirmed by sequence, but this was nonsense mutation. C106, CX-1, HT-29, SK01, SW480, SW620 and VACO400 in CHK2 exon 1b were confirmed to have the same nonsense mutation in 11609 A > G. DLD-1 and HCT-15 in CHK2 exon 2 were confirmed to have missense mutation R145W, which was heterozygous C > T missense mutation at nucleotide 433, leading to an Arg > Trp substitution within the FHA domain.


CONCLUSIONS
The CHK2 mutation in colorectal cancer is a low frequency event. There are just 10 cell lines to have sequence variations in all the 14 exons in 56 colorectal cancer cell lines and only DLD-1/HCT-15 had heterozygous missense mutation. These findings may give useful information of susceptibility of colorectal cancer as single nucleotide polymorphysim.
Liu
Wei-dong
WD
National Hepatobiliary and Enteric Surgery Research Center, Ministry of Health, Xiangya Hospital, Central-south University, Changsha, China.
Zhong
Bai-yun
BY
Zhang
Yang-de
YD
Choi
Gyu-seog
GS
D045744:Cell Line, Tumor; D064447:Checkpoint Kinase 2; D002851:Chromatography, High Pressure Liquid; D015179:Colorectal Neoplasms / Q000235:genetics*; D004249:DNA Damage; D006801:Humans; D009154:Mutation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*
D064447:Checkpoint Kinase 2; C578634:CHEK2 protein, human; D017346:Protein Serine-Threonine Kinases