title: Intron 9 retention in gene transcripts suggests involvement of CD44 in the tumorigenesis of ovarian cancer.
abstract: Increased or de novo expression of certain CD44 variant isofoms as well as abnormal processing of pre-mRNA of the CD44 gene have been found in different malignant human tumors. Retention of the non-coding intron 9 sequence in CD44 mRNA especially, appears to be a discriminating aberrant splicing pattern in several cancer tissues and cells. We examined the expression of the CD44 intron 9 sequence in the mRNA of 45 permanent ovarian cancer cell lines and in normal ovarian tissue. Abnormal retention of intron 9 was found in 19 (60%) cell lines expressing CD44 std. Normal ovarian tissue as well as all ovarian cancer cells without CD44 s t d expression were found to be negative for intron 9 retention. Our results indicate that besides newly acquired expression of certain CD44 isoforms abnormal retention of the non-coding intron 9 sequence in CD44 gene transcripts is also a common and maybe crucial event in the tumorigenesis of ovarian cancer. Since intron 9 is not retained in normal ovarian tissue this aberration might serve as a marker for human adenocarcinoma of the ovary.
authors.affiliation: Department of Biochemistry, Baylor College of Medicine, Houston, Tx. 77030, USA. elmars@bcm.tmc.edu
authors.forename: E
authors.initials: E
authors.lastname: Stickeler
authors.forename: V J
authors.initials: VJ
authors.lastname: Möbus
authors.forename: D G
authors.initials: DG
authors.lastname: Kieback
authors.forename: P
authors.initials: P
authors.lastname: Kohlberger
authors.forename: I B
authors.initials: IB
authors.lastname: Runnebaum
authors.forename: R
authors.initials: R
authors.lastname: Kreienberg
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000276:immunology / Q000473:pathology*; D015703:Antigens, CD / Q000096:biosynthesis / Q000235:genetics; D002460:Cell Line; D017931:DNA Primers; D005260:Female; D014644:Genetic Variation; D006801:Humans; D018960:Hyaluronan Receptors / Q000096:biosynthesis* / Q000235:genetics*; D007438:Introns; D010051:Ovarian Neoplasms / Q000235:genetics* / Q000276:immunology / Q000473:pathology*; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis; D014158:Transcription, Genetic
chemical_list: D015703:Antigens, CD; D017931:DNA Primers; D018960:Hyaluronan Receptors; D012333:RNA, Messenger