摘要:

AbstractStudies of mutant genotypes of the retinoblastoma susceptibility gene(RBI)in different solid tumors have mainly been concentrated on the demonstration of loss of heterozygosity (LOH) at both internal and external polymorphic sites. One reason for this is the complex organization of the gene. The p105RB protein has been shown to interact with both DNA and regulatory cellular proteins and oncoproteins. The amino acids encoded by exon 21 are implicated in several of these interactions. Both point mutations and intragenic deletions involving exon 21 have previously been reported in human tumors. We have examinedRBIexon 21 from a number of human tumor types where significant LOH in or around theRBIgene has been reported. DNA from 78 primary tumors was amplified using the polymerase chain reaction (PCR) with primers covering exon 21, followed by constant denaturant gel electrophoresis (CDGE). The 78 tumors included 11 breast carcinomas, 30 nonsmall cell lung carcinomas, 6 colon carcinomas, and 31 sarcomas. The small cell lung cancer cell line NCI‐H209, previously shown to harbour a point mutation in codon 706: TGT‐>TTT (Cys‐>Phe), was detected using CDGE. Apart from this control mutant cell line, we did not detect any mutations in the examined region in any of the t

ISSN:1045-2257    

DOI:10.1002/gcc.2870050202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractWe previously reported the non‐random occurrence of monosomy 22 in rhabdoid or atypical teratoid tumors of the brain in three young children. We now present cytogenetic and molecular studies of an additional rhabdoid tumor with the karyotype 46.XX, ‐ 9,‐22, + i( 1q), + der(22)t(9;22)(p 13;q11)/45,XX, ‐ 9,‐10,‐22, + i(1q), + der(22)t(9;22)(p 13;q11). These studies further demonstrate the involvement of chromosome 22, and they begin to define the critical region containing a gene or genes involved in the development or progression of rhabdoid tumors o

ISSN:1045-2257    

DOI:10.1002/gcc.2870050203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractPreliminary studies ofRASmutational activation in human testicular germ cell neoplasms have yielded conflicting results. Whereas two studies of clinical material revealed a significant incidence ofN‐ andKRASmutations, two studies of a variety of germ cell lines failed to documentRASmutations. To clarify the incidence ofRASmutations in these tumors, we studied archival paraffin‐embedded, formalin‐fixed orchiectomy specimens from 25 nonseminomas (NSGCT), 18 seminomas (SEM), and one Leydig cell tumor. For 14 of the 44 neoplasms, DNA was also available from nonmalignant testis adjacent to the tumor. Six age‐matched patients had testes removed because of nonmalignant disease and were studied as controls. Polymerase chain reaction (PCR) amplified the K‐, N‐, andHRAS12, 13, and 61 codons of these specimens, and mutations were detected with mutation‐specific oligonucleotide probe hybridization of Southern and slot blots. Four mutations were found inKRAS12 (4/44,[9.1 %]). One seminoma [1/18(5.6%)]contained the mutation GGT(GLY) → CGT(ARG), and three NSGCT [3/25(12%)] were found to have GGT(GLY) → GAT(ASP) mutations. One of the NSGCT mutations was detected in adjacent nonmalignant tissue, but the corresponding tumor did not contain any detectable mutation. No mutations were detected at KRAS 13 or 61, in NRAS orHRAS12, 13, or 61, or in the control normal testes. PCR, slot blots, and hybridizations were performed twice by two separate investigators for confirmation of results. PCR‐generated mutation‐specific positive controls were created for all possible RAS mutations, and these along with wild‐type DNA controls were integral to interpretation of the oligonucleotide mismatch hybridization assay. By using positive and negative controls, we have detected a relatively low incidence of RAS mutations in archival human test

ISSN:1045-2257    

DOI:10.1002/gcc.2870050204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractHomozygous deletions are instrumental in the detection and cloning of tumor suppressor genes. We report the isolation and characterization of 39 new single‐copy probes saturating a submicroscopic homozygous deletion detected in the DNA of the small cell lung cancer (SCLC) cell line U2020. The probes were selected from a large collection, covering the entire length of chromosome 3 with an estimated average spacing of 100–150 kb. Based on the number of probes in the deletion and the probe density, the size of the U2020 submicroscopic deletion was estimated to be in the range of 4–7 megabases. Among the deleted loci, 17 showed conservation across species, probably representing potential coding gene sequences. By genetic and physical mapping of a large randomly chosen fraction of the deleted probes, we defined the location of the U2020 deletion within chromosome band 3p 12. Our cloning strategy is based on narrowing the region of interest by eliminating probes that retain heterozygosity in SCLC samples, thus selecting for probes in the region of common

ISSN:1045-2257    

DOI:10.1002/gcc.2870050205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractA case of myelodysplasia was found to have a complex bone marrow karyotype, involving an apparent whole‐arm translocation between 17q and 18q. The application of a simplified fluorescence in situ hybridization technique, using directly fluorochrome‐labeled centromere‐specific alpha‐satellite DNA probes, demonstrated the presence of sequences from both chromosomes 17 and 18 in the centromere of the derivative chromosome. This proves that a true whole‐arm translocation had occurred. The case exemplifies how in situ hybridization analysis can be used to resolve interpretation problems in cancer cyt

ISSN:1045-2257    

DOI:10.1002/gcc.2870050206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractThe analysis of 2,550 kb from 11 p 13 in Wilms' tumor (WT) material revealed two regions that differed significantly in their methylation between tumor and normal tissue. In WT a hypomethylated area defined by anNrulandMlulrecognition site 100–150 kb centromeric of the WT geneWTI(site A) and hypermethylation defined by anNrulandSacllsite 100 kb telomeric of theWTIgene were found (site B). The degree of methylation in region B varied between 20 and 100% in the different samples; the highest level was observed in tumors without preoperative chemotherapy. The CpG island 5′ of theWTIgene was partially methylated in 2/29 tumors analyzed. The methylation state of regions A and B could reflect the normal pattern present in a subset of embryonal kidney cells, from which WT devel

ISSN:1045-2257    

DOI:10.1002/gcc.2870050207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractNeuroblastoma tumors are characterized by aberrations of chromosome I. Rapid detection of these chromosomal aberrations at diagnosis could give important clues to outcome and therapy. We attempted to detect numerical and structural aberrations of chromosome I not only by classical metaphase cytogenetics but also by interphase cytogenetics in order to overcome difficulties of karyotyping due to diminished metaphase quality and quantity in primary neuroblastoma samples. Karyotypic changes of chromosome I in 53 primary neuroblastomas were evaluated. In addition, we successfully performed interphase cytogenetics using single and double in situ hybridization procedures with chromosome I ‐specific repetitive DNA probes on nuclei preparations obtained from 46 and 20 tumors, respectively. Polysomies of structurally normal chromosomes I were predominantly seen in tumors with good prognosis, whereas deletions of 1p material were nearly exclusively confined to progressive tumors. Numerical and structural chromosome I aberrations as studied by metaphase and interphase cytogenetics are thus valuable prognostic markers in neuroblastom

ISSN:1045-2257    

DOI:10.1002/gcc.2870050208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractHuman papillomavirus (HPV) types 16 and 18 integration sites were mapped in six HPV‐immortalized human keratinocyte cell lines by fluorescence in situ hybridization (FISH). Mapping of HPV sequences in these cell lines revealed that HPV integration varied in copy number and location but that integration sites were stable over extended passages in culture. Integration occurred at different sites throughout the genome and did not correspond to the location of specific cellular genes. However, integration sites were consistent with integration near or within known fragile sites in five of the six cell lines. Induction of aphidicolin‐sensitive fragile sites in one cell line prior to in situ hybridization revealed that integrated HPV DNA was disrupted by fragile‐site expression, suggesting that integration occurred within a fragile

ISSN:1045-2257    

DOI:10.1002/gcc.2870050209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractThe translocation t( 11; I4)(q 13;q32) has been described in a spectrum of B‐lymphoproliferative diseases and involves a putative oncogene,BCLI, which maps to chromosome band 11q13. Recent evidence indicates that this abnormality may delineate particular subtypes of lymphoma, such as intermediate lymphocytic and centrocytic lymphomas. Thus the possible significance of the t(111;14) within B‐cell disorders should be reexamined in the light of a more objective approach to classifying these diseases by morphology, histology, and immunophenotype. We describe 16 patients with t(11;14)(q13;q32) from a series of 90 patients with chronic lymphoid disorders in whom clonal chromosome abnormalities were detected. All the cases were leukemic: prolymphocytic (B‐PLL;4/15cases), chronic lymphocytic leukemia (CLL) with increase in prolymphocytes (2/9cases), or non‐Hodgkin lymphoma in leukemic phase, intermediate (3/4cases), lymphoplasmacytic (2/2cases), splenic lymphoma with villous lymphocytes (4/18cases), and follicular (I case). None of the CLL (25) or hairy cell leukemia cases (15) had t(11;14). Our findings showed that t(11;14) occurred in leukemias of mature B cells with lymphoplasmacytic features as judged by morphology and immunoph

ISSN:1045-2257    

DOI:10.1002/gcc.2870050210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractThe t(8;21)(q22;q22) is a nonrandom cytogenetic abnormality associated with acute myelogenous leukemia of the M2 subtype (FAB classification). The 8q‐ and 21q+ derivative chromosomes have previously been isolated in somatic cell hybrids and used to map the anonymous sequences D21S65 and D21S17, which were proximal and distal, respectively, to the breakpoint on chromosome 21. DNA from a series of 12 t(8;21) patients and 7 controls was analyzed by pulsed field gel electrophoresis. Physical linkage of probes D21S65 and D21S17 on a 2100 kbNrulfragment was established by partial digestion experiments. In all the patients, the translocation generated a rearranged D21S65Nrulfragment of 650 to 750 kb, suggesting heterogeneity in the breakpoints. This heterogeneity was confirmed by using BssHII,Sacll, andEaglenzymes. Our results are consistent with the presence of a 100 Kb breakpoint cluster region on chromosome 21 encompassing theAMLIgene. Interestingly, in half of the patients, demethylation of anNrulsite located 7 kb proximal to the last exon of theAMLIgene occurred on the nontranslocated chromosome 2

ISSN:1045-2257    

DOI:10.1002/gcc.2870050211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY