High throughput detection of M6P/IGF2R intronic hypermethylation and LOH in ovarian cancer.
Cell surface mannose 6-phosphate/insulin-like growth factor II receptors (M6P/IGF2R) bind and target exogenous insulin-like growth factor II (IGF2) to the prelysosomes where it is degraded. Loss of heterozygosity (LOH) for M6P/IGF2R is found in cancers, with mutational inactivation of the remaining allele. We exploited the normal allele-specific differential methylation of the M6P/IGF2R intron 2 CpG island to rapidly evaluate potential LOH in ovarian cancers, since every normal individual is informative. To this end, we developed a method for bisulfite modification of genomic DNA in 96-well format that allows for rapid methylation profiling. We identified ovarian cancers with M6P/IGF2R LOH, but unexpectedly also found frequent abnormal acquisition of methylation on the paternally inherited allele at intron 2. These results demonstrate the utility of our high-throughput method of bisulfite modification for analysis of large sample numbers. They further show that the methylation status of the intron 2 CpG island may be a useful indicator of LOH and biomarker of disease.
Huang
Zhiqing
Z
Division of Gynecologic Oncology, Duke University Medical Center, Durham, NC 27708, USA.
Wen
Yaqing
Y
Shandilya
Ruby
R
Marks
Jeffrey R
JR
Berchuck
Andrew
A
Murphy
Susan K
SK
D000483:Alleles; D018899:CpG Islands; D019175:DNA Methylation; D005260:Female; D006801:Humans; D007438:Introns; D019656:Loss of Heterozygosity; D010051:Ovarian Neoplasms / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods*; D017527:Receptor, IGF Type 2 / Q000235:genetics*; D017422:Sequence Analysis, DNA; D013447:Sulfites / Q000737:chemistry
D017527:Receptor, IGF Type 2; D013447:Sulfites; C009279:sodium bisulfite