Loss of imprinting in IGF2 in colorectal carcinoma assessed by microdissection.
To ascertain the implications of loss of imprinting (LOI) of the insulin-like growth factor II gene (IGF2) for carcinogenesis, the precise frequency of LOI in colorectal carcinoma was examined using a laser capture microdissection method, and compared to the matched normal colorectal mucosa. LOI was examined by PCR-restriction fragment length polymorphism in combination with direct sequencing. The status was assigned as imprinting when PCR-RFLP showed only one band or sequence with a single peak, otherwise cases were classified as LOI. LOI was found in 13 of 24 informative cases of carcinoma (54%), which was higher than the ratios reported previously. LOI was also found in the normal colorectal mucosae in 14 cases (58%). The LOIs in carcinomas and in the normal mucosae were closely correlated: 10 of 13 LOI-positive carcinomas showed LOI in the matched normal mucosae. These results suggest that LOI of IGF2 in colorectal carcinoma and LOI in the background mucosa play important roles in carcinogenesis.
Maenaka
Shiori
S
Department of Laboratory Sciences, School of Health Sciences, Kanazawa University Faculty of Medicine, Kanazawa, Japan.
Hikichi
Tetsurou
T
Imai
Miwa A
MA
Minamoto
Toshinari
T
Kawahara
Ei
E
D001665:Binding Sites / Q000235:genetics; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D004273:DNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism; D018392:Genomic Imprinting / Q000235:genetics*; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology; D007834:Lasers; D042282:Microdissection / Q000379:methods*; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length
D004273:DNA, Neoplasm; D007335:Insulin-Like Growth Factor II; D015252:Deoxyribonucleases, Type II Site-Specific; C038485:GGGCCC-specific type II deoxyribonucleases