title: Loss of heterozygosity on chromosome 7q in in vitro-immortalized human oral keratinocyte cell lines.
abstract: Loss of heterozygosity in two in vitro-immortalized human oral keratinocyte cell lines was analysed by polymerase chain reaction using 42 polymorphic microsatellite markers on chromosomes 4, 6, 7 and 15. These chromosomes are regarded as candidates for harbouring genes involved in the immortalization of human cells or tumour-suppressor genes in several tumours, including oral cancers, and karyotypic analysis has revealed that both cell lines have non-random alterations in these chromosomes. No allele losses were detected at any informative loci on chromosomes 4 and 6 in the cell lines, including genomic regions adjacent to putative human tumour-suppressor genes and putative senescence genes. When analysed for loss of heterozygosity on chromosomes 7 and 15, allele losses common to both cell lines were detected in the regions at 7q11.2, 7q21.1-21.3 and 7q31.1. High frequencies of loss of heterozygosity on chromosome 7q in at least two distinct regions, particularly centred around 7q31, are observed in a variety of tumours, including oral squamous-cell carcinoma, suggesting that multiple genes involved in immortalization of these cell lines might be present on chromosome 7q.
authors.affiliation: Oral and Maxillofacial Surgery, The Nippon Dental University Hospital at Tokyo, 2-3-16 Fujimi, Chiyoda-ku, Tokyo 102-8158, Japan.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Arai
authors.forename: Nobumasa
authors.initials: N
authors.lastname: Shigeeda
authors.forename: Minoru
authors.initials: M
authors.lastname: Uchida
authors.forename: Takeki
authors.initials: T
authors.lastname: Tsutsui
mesh_terms: D002461:Cell Line, Transformed / Q000502:physiology* / Q000821:virology; D002884:Chromosomes, Human, Pair 15 / Q000235:genetics; D002894:Chromosomes, Human, Pair 4 / Q000235:genetics; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics*; D006801:Humans; D015603:Keratinocytes / Q000502:physiology*; D019656:Loss of Heterozygosity; D018895:Microsatellite Repeats; D009061:Mouth Mucosa / Q000166:cytology; D016133:Polymerase Chain Reaction