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PubMed2001

Transitional cell carcinoma of the endometrium associated with a benign ovarian Brenner tumor: a case report.

Transitional cell carcinomas (TCCs) of the endometrium are rare, and only 10 cases have been described to date. We report the case of a 46-year-old woman who developed both a TCC of the endometrium and a benign ovarian Brenner tumor. Such an association has not yet been reported in the literature. Immunohistochemical studies of the uterine tumor showed cytokeratin 7 positivity and cytokeratin 20 negative staining, which was consistent with a Müllerian derivation. Human papilloma virus (HPV) immunostaining as well as polymerase chain reaction (PCR) analysis using primers for HPV types 6, 11, 16, and 18 failed to detect viral DNA. The coexistence of a TCC of the endometrium and an ovarian Brenner tumor might be coincidental but raises the possibility of a field effect, as seen with multifocal endometrioid tumors or multiple urinary tract TCCs.

Brenner Tumor↗
PubMedDate not supplied

Bovine papillomavirus type 4 in oesophageal papillomas of cattle from the south of Italy.

Oesophageal papillomas are known to occur in cattle infected with bovine papillomavirus type 4 (BPV-4), and BPV-4 papillomas may undergo malignant progression in cattle that feed on bracken fern. In the south of Italy, where bracken fern is common, examination of 1133 slaughterhouse cattle aged 4-12 years revealed oesophageal lesions (single or multiple peduncuolated proliferations, or mucosal thickening) in 147 (13%). These two types of lesion were consistent with exophytic and inverted papilloma, respectively. BPV-4 was detected by polymerase chain reaction (PCR) analysis in >60% of the samples in which oesophageal papilloma was diagnosed histopathologically. Nucleotide sequencing of the PCR amplicons confirmed the presence of BPV-4 in the papillomas. This is the first report of such infections in a European country other than Britain.

Animals↗
PubMed1976

Do highly oncogenic group A human adenoviruses cause human cancer? Analysis of human tumors for adenovirus 12 transforming DNA sequences.

Adenovirus 12 (Ad12) (Huie) (highly oncogenic group A) readily induces tumors in newborn rodents. Since Ad12 is isolated from human fecal samples, we investigated whether it plays a role in the etiology of human gastrointestinal cancer. If Ad12 is a causal agent of human cancer, then human tumors should contain Ad12 transforming genes, as indicated by studies of cells transformed in vitro and in vivo by oncogenic viruses. Ad12 DNA and the Ad12 transforming restriction fragment (EcoRI-C fragment, left 16% of the viral genome) were labeled in vitro to 10(7) to 4 X 10(8) cpm/mug by the nick translation reaction of DNA polymerase of Escherichia coli. The fidelity and sensitivity of these probes were established by (i) analysis of DNA from Ad12-transformed cells and from hamsters with tumors induced by Ad12, (ii) reconstruction experiments with added Ad12 DNA and EcoRI restriction fragments, and (iii) comparison of annealing characteristics with Ad12 probes labeled in vivo. With Ad12 [3H]DNA as probe, no viral DNA sequences were detected in 18 normal gastrointestinal tissues and 34 gastrointestinal tumors, including cancers of the colon, rectum, small intestine, and stomach, under conditions that would detect 0.1 copy of the Ad12 genome per tumor cell. Similar analyses of Ad12-transformed hamster cells and Ad12 primary hamster tumors indicated 6-18 copies per cell of over 90% of the viral genome. With the Ad12 EcoRI-C transforming fragment as probe, no hybridization was detected with 32 human gastrointestinal tumors and five normal tissues; this result excludes 1-2% of the Ad12 genome per tumor cell. Our date are strong evidence that Ad12 is not a major cause of human gastrointestinal cancer. The Ad12 transforming EcoRI-C fragment hybridized (50-68% efficiency) with other Ad12 isolates and with Ad18 and 31 (members of oncogenic group A), but not at all with 28 other human Ad serotypes (manuscript in preparation). Thus other group A members probably are also not involved in human gastrointestinal cancer. No viral DNA sequences were detected in 12 normal lungs and 22 lung tumors, suggesting that respiratory cancer does not involve an Ad12 etiology.

Adenoviruses, Human↗
PubMed1982

Human papillomavirus DNA in cutaneous primary and metastasized squamous cell carcinomas from patients with epidermodysplasia verruciformis.

DNA extracted from squamous cell carcinomas from patients with the chronic wart disease syndrome, epidermodysplasia verruciformis, was analyzed for the presence of human papillomavirus (HPV)-specific DNA sequences by Southern blot hybridization analysis. Employing an HPV probe obtained by molecular cloning of viral DNA purified from benign warts from these patients, we have unequivocally identified HPV-specific nucleotide sequences in squamous cell carcinomas from these patients. Restriction endonuclease mapping indicated that the DNA present in the carcinomas was of the same type (type 5) as that found in the benign tumors from these patients and was present as unintegrated, free viral DNA. Moreover, we have demonstrated the presence of HPV-5 DNA in a subcutaneous metastatic tumor from one of these patients. This latter observation essentially eliminates the possibility that the HPV-5 DNA present in the malignant tumors in these patients resulted from cross-contamination from an adjacent benign warty lesion. In addition to wild-type HPV-5 DNA, both the primary and metastatic carcinomas analyzed also contained an HPV-5 DNA species lacking approximately 20% of the HPV-5 DNA genome. These subgenomic forms of HPV-5 DNA could not be detected in benign papillomas from these patients.

Carcinoma, Squamous Cell↗
PubMed1994

Accumulation of genetic alterations during esophageal carcinogenesis.

Using polymerase chain reaction amplification of microsatellite regions in DNA from 11 epithelial dysplasias of the esophagus and 21 early squamous cell carcinomas, we were able to detect frequent loss of heterozygosity (LOH) on chromosomes 3p21.3 and 9q31 even in low-grade dysplasias. In contrast, we observed frequent LOHs on chromosomes 9p22 and 17p13 (TP53 locus) only in high-grade dysplasias and carcinomas, but not in any low-grade dysplasias. Analysis of LOH at the same four chromosomal regions in DNA of five additional minimal carcinomas and accompanying dysplastic lesions revealed loss of alleles at the loci on 3p21.3 and 9q31 throughout various degrees of dysplasia and carcinoma; again, LOHs on 9p22 and 17p13 occurred only in high-grade dysplasia and carcinoma in situ. Our results indicated that inactivation of putative tumor suppressor genes on 3p21.3 and 9q31 may be early genetic events during esophageal carcinogenesis, and that additional genetic alterations on 9p22 and 17p13 probably play roles in progression.

Cell Transformation, Neoplastic↗
PubMed1994

Microsatellite instability in sporadic endometrial carcinoma.

BACKGROUND: Recent studies have demonstrated ubiquitous somatic microsatellite mutations in some cancers of the colon, endometrium, stomach, and pancreas. PURPOSE: Our purpose was to characterize the frequency and nature of this replication error (RER) or mutator phenotype in sporadic endometrial carcinoma. METHODS: Formalin-fixed, paraffin-embedded normal and tumor tissues from 45 patients with sporadic endometrial cancer were screened for the RER phenotype at three microsatellite loci. To further characterize when these alterations were acquired relative to clonal expansion, the sizes of the altered microsatellites in different tumor and normal regions were determined using selective UV radiation fractionation. Approximately 150-300 histologically defined cells on stained tissue sections were covered with small ink dots, and UV irradiation was used to destroy the DNA of cells not covered by ink. Undamaged DNA from seven to 25 spots per section were extracted, then analyzed at the Mfd27, Mfd41, and Mfd47 microsatellite loci and also at the c-K-ras gene locus with individual polymerase chain reactions. Radioactively labeled amplified DNAs were analyzed by electrophoresis and autoradiography. Fisher's exact test and the logrank test were used for statistical analysis. RESULTS: The RER positive (RER+) phenotype was detected in nine (20%) of 45 sporadic endometrial carcinomas. The topographic tissue distributions of the altered microsatellites revealed clues to their pathogenesis. The RER+ phenotype was homogeneously present in the primary tumors and their metastases and was absent from adjacent normal and hyperplastic endometrium. The altered microsatellites were predominantly the same sizes throughout five tumors but demonstrated greater intratumor heterogeneity in three tumors. In one case, the primary tumor was stable but its metastasis was unstable. Mutant c-K-ras alleles were significantly more frequent in RER+ (56%) than in RER negative (RER-) (14%) tumors (P = .0165) and appeared to be acquired after the RER+ phenotype in one tumor. There were no significant clinical differences between the RER+ and RER- tumors. CONCLUSIONS AND IMPLICATIONS: The RER+ phenotype is frequently present in sporadic endometrial cancers and is expressed before and during clonal expansion. The underlying mutator mutations are probably heterogeneous, since the RER+ phenotypes were diverse. The absence of altered microsatellites in adjacent normal endometrium demonstrates that the expression of the RER+ phenotype is limited to neoplastic tissue. The bulk of the microsatellite alterations appeared to be acquired prior to clonal expansion, suggesting that expression of the underlying genomic instability contributes to, and is not a consequence of, transformation.

Adult↗
PubMed1983

Isolation of DNA fragments from chromosome 13.

A number of patients with retinoblastoma have a deletion of chromosome 13. Comparison of the deleted segments from different individuals reveals that all deletions involve chromosome band 13q14. This observation has lead to the hypothesis that in this region is a gene of genes important in the etiology of retinoblastoma. As a first step toward understanding those genes, the authors successfully isolated five DNA fragments from chromosome 13 using recombinant DNA techniques. The DNA fragments from chromosome 13 will be useful in identifying DNA polymorphic sites that are linked to the retinoblastoma locus tentatively assigned to 13q14. Such DNA polymorphisms will be important in the genetic counselling of families with retinoblastoma. These chromosome 13q14 fragments also may be useful in searching for microdeletions of 13q14.

Animals↗
PubMed2001

Physical state of HPV16 and chromosomal mapping of the integrated form in cervical carcinomas.

Using a procedure based on restriction enzyme cleavage, self-ligation, and inverse polymerase chain reaction (rliPCR), the authors investigated 18 cervical intraepithelial neoplasia III (CIN III) cases and 37 invasive squamous carcinomas for integration of human papillomavirus type 16 (HPV16). All eighteen CIN III cases (severe dysplasia or high-grade squamous intraepithelial lesion) were found to harbor episomal HPV, but one of the samples contained mixed episomal and integrated forms. Seventeen of 37 invasive cervical carcinoma samples were identified previously as containing the completely integrated HPV16 genome by using PCR covering the entire E1/E2 gene, and this was confirmed by rliPCR in 16 cases. One case, however, showed a low level of episomal deoxyribonucleic acid in addition to the predominant integrated form. Of the remaining 20 carcinoma samples showing episomal forms in the previous analysis, 14 were found to contain integrated forms using rliPCR, and four contained multimeric episomal forms. Thus, in total, 31 of 37 of the carcinomas (84%) showed the integrated HPV16 genome. The rliPCR product from five carcinoma cases was cloned into a plasmid vector and used as a template for "primer walking" deoxyribonucleic acid sequencing to deduce human sequences flanking the integrated HPV genome. Based on this information, bacterial artificial chromosome (BAC) and P1-derived artificial chromosome (PAC) clones were obtained and used as probes in fluorescent in situ hybridization experiments on human metaphase chromosomes. The results of the fluorescent in situ hybridization experiments showed evidence for HPV16 integration in chromosome regions 1q25, 3q28, 6p25, 11p13, and 18q22. Sixteen carcinoma samples, containing episomal HPV16, were sequenced in the long control region. Evidence for changes in E2 binding or silencer YY1 sequences was found in only two samples.

Blotting, Southern↗
PubMed1992

Detection of p53 gene mutations in human ovarian and endometrial cancers by polymerase chain reaction-single strand conformation polymorphism analysis.

The presence of mutations in the p53 gene was examined in ovarian cancers by a polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis. The primers were designed to amplify exons 5 through 9 that contain phylogenetically conserved domains of the p53 gene. Mutations were detected in 5 out of 10 cases, one of which contained a deletion in the second allele. A single base substitution was detected in 4 cases at codons 162, 175, 205 and 273 and a single base insertion in one case within codon 315. A high frequency of p53 mutations in ovarian cancers and lack of mutation in 6 benign ovarian tumors and 2 normal ovaries suggested that the mutation of the p53 gene was associated with the genesis and/or progression of ovarian cancer. In 1 of 7 endometrial cancers, two mutations at codons 239 and 254 were detected.

Alleles↗
PubMed1996

Clonal heterogeneity in human esophageal squamous cell carcinomas on DNA analysis.

Cancers are thought to arise through multistep accumulation of somatic mutations in the progeny of a single cell. Multiple mutations may induce molecular intratumor heterogeneity. Therefore, we examined molecular clonal heterogeneity in esophageal squamous cell carcinomas. Twenty-four esophageal squamous cell carcinomas and associated lymph node metastases were examined for microsatellite alterations, and abnormalities of the p53 and transforming growth factor-beta type II receptor (TGF-beta RII) genes. There were eight cases (33%) showing different patterns of loss of heterozygosity in primary tumors and metastatic lymph nodes with microsatellite markers. On the other hand, the abnormalities of p53 were identical in all these cases. No mutation was detected in the simple repeated sequences of the TGF-beta RII gene. These results indicate that molecular clonal heterogeneity exists in esophageal squamous cell carcinomas. Therefore, care is necessary in preoperative genetic diagnosis using biopsy samples.

Carcinoma, Squamous Cell↗
PubMed1996

Allelic loss of chromosome 16q in endometrial cancer: correlation with poor prognosis of patients and less differentiated histology.

Deletion of certain chromosomal regions can be demonstrated in malignant cells. Chromosome 16q is one of the regions where allelic loss is frequently detected in carcinoma of the breast and many other tumors, suggesting that gene(s) which retard tumor growth may exist here. To elucidate the clinicopathological significance of chromosome 16q, loss of heterozygosity (LOH) was investigated using microsatellite polymorphism analysis in 58 patients with endometrial lesions (50 with endometrial carcinoma and 8 who had hyperplasia with or without atypia). When 11 regions of chromosome 16q were examined, LOH was found in 20 patients with carcinoma (40%) and none of the patients with hyperplasia. The tumors of 9 of the 20 patients (45%) showed total loss of 16q, while the others (55%) showed partial deletion. Tumors with LOH were histologically less differentiated than those without LOH (P = 0.038, chi2 test). Patients with tumors showing LOH of 16q had a worse prognosis than those without LOH according to Kaplan-Meier survival analysis (P=0.0158, log-rank test). In addition, LOH of 16q showed a significant relationship to prognosis by Cox regression analysis. Deletion mapping of 16q demonstrated that two regions (16q22.1 and 16q22.2-23.1) were frequently involved. Patients with 16q22.1 LOH had a poorer prognosis than those with intact 16q22.1 (P=0.0003, log-rank test). These findings suggest that gene(s) of which defect is possibly related to the aggressiveness of endometrial cancer are localized on a limited region of 16q that includes 16q22.1.

Alleles↗
PubMed1991

Genomic DNA analysis of rat retinal tumor induced by adenovirus type 12.

To elucidate the pathogenesis of human retinoblastoma, we investigated the genomic expression in retinal tumors induced by human adenovirus type 12 in rats, using various DNA probes. Seven rats received a single intraocular inoculation of concentrated virus fluid within 24 hours after birth. Intravitreous tumors were induced in two out of seven animals (28.5%) within 30 to 64 days after the inoculation. A remarkably uniform histologic feature, i.e., neuroblastic cells in association with Homer-Wright pseudorosettes, was present in all cases. The adenovirus-related oncoprotein gene E1A and human retinoblastoma susceptibility gene were detected in the tumors by Southern blot hybridization. In situ hybridization analysis demonstrated expression of adenovirus type 12 E1A gene in the inner granular layer of the retina. It was suggested that integration of adenovirus type 12 E1A fragment with the host genome and expression of the gene were required for induction of this tumor.

Adenovirus Infections, Human↗
PubMed1972

Growth characteristics of Kilham rat virus and its effect on cellular cellular macromolecular synthesis.

Kilham rat virus (KRV) is adsorbed into the rat nephroma cell within 1 hr after infection. There follows a latent period of about 12 hr during which less than 1% of the input infectious virus can be accounted for. New infectious virions can be detected at about 12 hr and the maximal yield of virus is attained by 23 hr after infection. The increase in final virus yield is about 200-fold over that found in the latent period. During this 23-hr period of virus growth, the rate of protein synthesis remains 75 to 100% of that in the uninfected cell. Ribonucleic acid (RNA) synthesis during this period is maintained at 100 to 150% of that found in the control cells. The addition of the inhibitor of deoxyribonucleic acid (DNA) synthesis, 5-fluoro-deoxyuridine (FUDR), up to 8 hr after infection completely suppresses virus production. After 8 hr, viral DNA production has started and FUDR inhibition progressively decreases until by 23 hr the addition of the inhibitor no longer causes a reduced virus yield. Viral DNA synthesis once initiated is required for the remainder of the 23-hr virus cycle. Viral DNA synthesis probably begins about 4 hr before the production of infectious virions. In the KRV-infected cells, DNA synthesis decreased sharply for 6 to 7 hr after infection in comparison to the uninfected cell. At 7 to 8 hr after infection, DNA synthesis in the infected cell increased and was maintained at a higher level than in the control cells for the rest of the virus growth period.

Amino Acids↗
PubMed1985

Two Shope papillomavirus-associated VX2 carcinoma cell lines with different levels of keratinocyte differentiation and transplantability.

Two cell lines, named VX2T and VX2R, were isolated from the transplantable VX2 carcinoma, a wholly anaplastic tumor established from a carcinoma induced by the Shope cottontail rabbit papillomavirus (CRPV) (J.G. Kidd and P. Rous, J. Exp. Med. 71:813-838, 1940). The CRPV genome was found to be maintained and transcribed in both cell lines, as in the VX2 carcinoma. The VX2T cells retained the tumor-producing capacity in the rabbit and the low expression of epidermal keratinocyte differentiation of the VX2 tumor cells. The VX2R cells, although tumorigenic for nude mice, were no longer serially transplantable in the rabbit and expressed differentiated functions of keratinocytes. These data indicate that the anaplastic characteristic and the transplantability of VX2 carcinoma cells to immune competent allogenic hosts may be lost without any detectable modification of the physical state and transcription of the CRPV genome.

Animals↗
PubMed1987

Mammary tumorigenesis in feral mice: identification of a new int locus in mouse mammary tumor virus (Czech II)-induced mammary tumors.

A population of Mus musculus subsp. musculus (Czech II), recently isolated from the wild, lack endogenous mouse mammary tumor virus (MMTV) proviral genomes. Some of these mice carry an infectious MMTV [designated MMTV (Czech II)] that is transmitted in the milk and is associated with mammary tumor development. This virus is distinct from laboratory strains of MMTV present in inbred mice. An MMTV (Czech II) genome was found within a 0.5-kilobase region of the cellular genome in five of 16 Czech II mammary tumors. MMTV insertion at this site activates expression of a 2.4-kilobase species of RNA from a previously silent cellular gene. This region of the cellular genome was designated int-3 since it is unrelated to the int-1 and int-2 loci. The int-3 locus does not appear to correspond to other proto-oncogenes but is well conserved among mammalian species.

Animals↗
PubMed2002

Tumor suppressor PTEN is mutated in canine osteosarcoma cell lines and tumors.

Canine osteosarcoma (OS) cell lines contain mutations that directly or indirectly inactivate the tumor suppressor genes p53 and retinoblastoma. Another important tumor suppressor, PTEN, is mutated in many human cancers. To determine whether inactivation of PTEN plays a role in the pathogenesis of canine OS, we studied its expression in canine OS cell lines and tumors. Four of five canine OS cell lines (CO2, C03, CO5, and CO7) constitutively express high levels of the phosphorylated form of Akt, an indirect indicator of aberrant PTEN expression. PTEN protein is essentially absent from three of these cell lines (CO2, CO5, and CO7), whereas C03 contains a potentially inactivating amino acid substitution in PTEN at codon 340. Genomic hybridization experiments indicate that CO2, CO5, and CO7 contain large deletions within the PTEN gene. Ten of 15 OS tumors exhibit variable or negative PTEN staining. Evaluation of a PTEN-negative staining tumor by Southern blotting indicates that the PTEN gene is deleted in this tumor. These results indicate that PTEN is mutated or downregulated in a high percentage of canine OS cell lines and tumors and likely plays an important role in the pathogenesis of the disease.

Animals↗
PubMed2000

The Epstein-Barr virus is rarely associated with esophageal cancer.

The Epstein-Barr virus is an agent that causes African Burkitt's lymphoma, infectious mononucleosis, and Hodgkin's disease. It is also related to nasopharyngeal carcinoma and gastric carcinoma. The aim of this study was to evaluate the prevalence of the Epstein-Barr virus in esophageal cancer. Polymerase chain reaction and in situ hybridization were used to detect the Epstein-Barr virus. We detected 103 Epstein-Barr virus positive cells out of 107 of KYSE 273 cells using first standard-PCR. Epstein-Barr virus DNA could not be detected in 30 of the esophageal squamous cell carcinoma cell lines and 2 of the Barrett's esophageal adenocarcinoma cell lines. Out of 77 esophageal cancer patients, 3 cases were found positive for Epstein-Barr virus DNA using polymerase chain reaction. However, by in situ hybridization we found signals in only 1 of the 3 cases, the signal was located in the infiltrating lymphocytes. The Epstein-Barr virus is rarely associated with esophageal cancer.

Adenocarcinoma↗