Alterations in promoter usage and expression levels of insulin-like growth factor-II and H19 genes in cervical carcinoma exhibiting biallelic expression of IGF-II.
Biallelic expression of insulin-like growth factor-II (IGF2) has been reported to be associated with progression of several tumors. Here, we report that the promoter usage and expression levels of IGF2 and H19 were altered in cervical carcinoma showing loss of imprinting. The imprinting status was examined in 32 cervical carcinomas and their matched normal tissues. Loss of imprinting (LOI) of IGF2 was observed in seven of 18 (39%) informative cases. LOI of H19 gene was detected in five of 14 informative cases. The usage of promoter P1 was observed in LOI tumors of IGF2, but not in the tumors showing maintenance of IGF2 imprinting (MOI) and in the normal cervical tissues. Unlike MOI tumors, some LOI tumors revealed the lack of IGF2 transcription from promoter P3. LOI tumors of IGF2 showed an increased expression level of IGF2 but a down-regulation of H19 relative to the normal tissues whereas MOI tumors did not reveal significant alterations. These results suggest that promoter P1 could be involved in the biallelic expression of IGF2 and that the altered expression levels of IGF2 and H19 gene might be associated with the progression of cervical carcinoma showing biallelic expression of IGF2.
Kim
Sung Jo
SJ
Comprehensive Gynecologic Cancer Center, Pundang CHA General Hospital, Sungnam, Kyonggi-do, South Korea.
Park
Sang Eun
SE
Lee
Chan
C
Lee
Sun Young
SY
Jo
Jin Ho
JH
Kim
Jung Mogg
JM
Oh
Yu-Kyoung
YK
D000483:Alleles; D005260:Female; D015870:Gene Expression; D018392:Genomic Imprinting; D006579:Heterozygote; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D062085:RNA, Long Noncoding; D012333:RNA, Messenger / Q000032:analysis; D022661:RNA, Untranslated / Q000235:genetics* / Q000378:metabolism; D002583:Uterine Cervical Neoplasms / Q000235:genetics* / Q000378:metabolism
C094335:H19 long non-coding RNA; D062085:RNA, Long Noncoding; D012333:RNA, Messenger; D022661:RNA, Untranslated; D007335:Insulin-Like Growth Factor II