Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously reported that continuous in vitro passage in the presence of 3T3 feeders of a non-tumorigenic adenoma-derived epithelial cell line, designated PC/AA, resulted in its becoming immortal. At early passage PC/AA was normal diploid, whereas every cell of PC/AA late passage had an isochromosome 1(q) which led us to suggest that abnormalities of chromosome 1 may be involved in tumour progression. We now report the isolation of a 3T3-feeder-independent variant of early-passage PC/AA, designated PC/AA/FI, which was immortal in vitro and remained non-tumorigenic. Each cell of PC/AA/FI again has an isochromosome 1(q), like the late-passage PC/AA. However, with PC/AA/FI it is the other chromosome 1 of the homologous pair which is involved in the formation of the isochromosome 1(q). This is possible to determine because of the polymorphic centromeric heterochromatin on chromosome 1 of the early-passage PC/AA. With the late-passage PC/AA (grown with 3T3 feeders) the homologue with the large C-band has given rise to an isochromosome 1(q) whereas with PC/AA/FI it is the other homologue with the smaller C-band which has given rise to this isochromosome. Both the immortal PC/AA/FI and the immortal PC/AA late passage, therefore, have independent abnormalities involving chromosome 1. These results indicate that chromosome 1 may be involved in in vitro immortalization.
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PMID:Possible involvement of chromosome 1 in in vitro immortalization: evidence from progression of a human adenoma-derived cell line in vitro. 253 35

Double fluorescence in situ hybridization with DNA probes specific for the (peri)centromeric regions of chromosomes 3, 7, 9, 11, 12, 18, and X was performed on fresh isolated nuclei and frozen tissue sections prepared from 2 nodular hyperplasias, 2 adenomas, and 7 papillary carcinomas of the thyroid in order to detect numerical chromosomal changes. Numerical chromosomal aberrations were found in all malignant specimens examined. A consistent presence of at least two trisomies was detected in most cases, especially in the follicular variant specimens; the highest degree of trisomy was observed for chromosome 12. Isolated monosomies of moderate degree for different chromosomes were found in 1 adenoma and 2 papillary carcinomas. Severe monosomy of chromosome 9 was the only significant feature observed in the single metastatic papillary carcinoma.
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PMID:Numerical chromosomal aberrations in thyroid tumors detected by double fluorescence in situ hybridization. 751 60

We report here the physical mapping of recurrent chromosome 12q13-q15 breakpoints in cell lines derived from primary myxoid liposarcoma, lipoma, uterine leiomyoma, and pleomorphic adenoma of the salivary glands. In fluorescence in situ hybridization (FISH) experiments, we first mapped the position of the chromosome 12 translocation breakpoint in uterine leiomyoma cell line LM-30.1/SV40 relative to loci COL2A1, D12S4, D12S17, D12S6, D12S6, D12S19, D12S8, and D12S7. It mapped between linkage probes CRI-C86 (D12S19) and p7G11 (D12S8). We then isolated YAC clones using CRI-C86- and p7G11-derived sequence-tagged sites, constructed corresponding YAC contigs of 310 and 800 kb, respectively, and established long-range physical maps of these. Cosmid clones LLNL12NCO1-98C10 and LLNL12NCO1-113D12 were isolated using STSs within the CRI-C86- and the p7G11-derived YAC contigs, respectively, and a mixture of them was used to routinely study the various tumor cell lines by FISH analysis. The chromosome 12 breakpoints of all tumor cell lines tested mapped between cosmids LLNL12NCO1-98C10 and LLNL12NCO1-113D12. None of the breakpoints appeared to map within any of the isolated YAC clones. Furthermore, FISH analysis using cosmid LLNL12-NCO1-144G3, which maps at the CHOP locus, revealed that the chromosome 12 breakpoints in all cell lines of the three benign solid tumors that were tested were located distal to the chromosome 12 translocation breakpoint with the CHOP gene in myxoid liposarcoma cells with t(12;16). In conclusion, our studies seem to indicate that the chromosome 12 breakpoints of myxoid liposarcoma, lipoma, uterine leiomyoma, and pleomorphic adenoma of the salivary glands are all clustered within the 7-cM interval between D12S19 and D12S8, with those of the benign solid tumors distal to CHOP. Finally, the MYF5 gene mapped telomeric to LLNL12NCO1-113D12, and the MIP gene mapped centromeric to the chromosome 12 translocation breakpoint in myxoid liposarcoma cells.
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PMID:Physical mapping of chromosome 12q breakpoints in lipoma, pleomorphic salivary gland adenoma, uterine leiomyoma, and myxoid liposarcoma. 802 Sep 67

We have hypothesized that metacentric and submetacentric chromosomes frequently observed in malignant canine tumors are a result of telomeric fusions. Therefore cells from a canine mammary pleomorphic adenoma were transformed with a plasmid containing the SV40 'early region', known to cause telomeric associations. Compared with non-transformed adenoma cells, the cells had a higher proliferative capacity and expressed the large SV40-T-antigen. Karyotype studies showed the conversion from a normal to an aberrant karyotype with an increase of bi-armed chromosomes resulting from fusions of acrocentric chromosomes. In addition, the length of the telomeric repeats (TTAGGG) was determined for an early and a late passage of the transformed cells by Southern hybridization. The length of the telomeric repeats was apparently longer in the 5th than in the 38th passage. In situ hybridization with a telomere-specific DNA revealed interstitial telomeric repeats in the bi-armed chromosomes. We have concluded that these findings reflect the clonal expansion of head-to-head-telomeric fusions of canine acrocentric chromosomes leading to dicentric chromosomes with a very short distance between the two centromeres. Our results support the idea that the apparent centric fusions that have been described in some canine tumors may in fact be the cytogenetic products of head-to-head-telomeric fusions.
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PMID:Evidence that metacentric and submetacentric chromosomes in canine tumors can result from telomeric fusions. 803 27

Previous cytogenetic studies have indicated that a subset of large bowel adenomas have distal 1p deletions. We addressed this question by examining 70 sporadic polyps (63 adenomas, 5 hyperplastic polyps, and 2 polyps of undetermined histology) from 55 patients for alterations at eight loci on the short arm of chromosome 1 and found allelic imbalance (AI) or loss of one allele (LOH) in 14 (20%). The locus most frequently changed was MSI, which maps to 1p33-35. Fluorescence in situ hybridisation with centromeric and telomeric probes for chromosome 1, performed for 11 polyps, did not yield an abnormal number of signals, in accordance with the interpretation that the observed AI and LOH were the result of interstitial deletions in 1p. Whereas allelic imbalance at five other loci (mapping to 5q, 8p, 10p, 11p and 17q) was found less frequently, and then mainly in large (> 2 cm) tumours, the 1p alterations were equally distributed among small (< 1 cm) and large polyps. They were preferentially found in left-side tumours. Instability at microsatellite loci--the mutator phenotype--is demonstrated by shifts in the electrophoretic mobility of normal alleles. The mutator phenotype was first associated with hereditary nonpolyposis colorectal cancer but is also occasionally found in sporadic colorectal carcinomas; however, it is still uncertain when in the adenoma-carcinoma sequence in this type of genomic instability arises. We therefore looked for it at 12 dinucleotide repeat loci and found that seven tumours (six adenomas and one hyperplastic polyp) from seven patients had acquired new alleles not seen in the patients' corresponding normal DNA. Our results suggest that inactivation of a putative suppressor gene distally in chromosome arm 1p is an early event in colorectal tumourigenesis. They also show that microsatellite instability can be detected in large bowel polyps, indicating that this phenomenon, too, probably plays a pathogenic role for some colorectal tumours early in the adenoma-carcinoma sequence.
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PMID:Deletion of 1p loci and microsatellite instability in colorectal polyps. 858 34

Carney complex (CC) is a familial multiple neoplasia and lentiginosis syndrome, transmitted in an autosomal dominant manner. It is the only familial form of cardiac and skin myxomas known and includes endocrine neoplasms causing Cushing's syndrome [primary pigmented nodular adrenocortical disease (PPNAD)] and acromegaly (GH-producing adenoma). The molecular defect leading to CC remains unknown, but was recently mapped to chromosome 2p16 by linkage analysis. This region has exhibited cytogenetic aberrations in atrial myxomas from patients with CC and harbors the hMSH2 and hMSH6 genes, which are involved in the preservation of microsatellite length stability of replicating human cells. In the present study, we examined 15 tumor and normal tissue specimens from 13 patients with CC [GH-producing adenoma (n = 1), adrenal tumors (PPNAD, n = 8), thyroid cancer (n = 1), normal adrenal gland (n = 1)] and 4 cultured cell lines [heart myxoma (n = 3) and eyelid myxoma (n = 1)]. Chromosome analysis was obtained by standard cytogenetic techniques. One of the myxoma cell lines and 3 PPNAD specimens contained multiple telomeric associations (tas). The normal adrenocortical tissue from a patient with PPNAD contained no apparent chromosomal anomalies, whereas the neighboring PPNAD tissue demonstrated tas. DNA was extracted from peripheral blood, tumor cell lines, and frozen or paraffin-embedded tissues and subjected to PCR amplification with primers from 64 microsatellite locations covering chromosomes 1 and 3-22 and 14 loci covering chromosome 2. The alterations detected were loss and gain of heterozygosity (LOH and GOH; 49% and 26%, respectively), deletions of both alleles (DEL; 10%), and microsatellite length instability (15%). GOH and LOH were the most frequent changes, with telomeric markers significantly over-represented (P < 0.05). Chromosomes 6, 11, 22, 10, and 19 demonstrated mostly LOH, GOH, or DEL in over 40% of the informative loci tested (73%, 59%, 47%, 46%, and 44%, respectively), whereas markers on chromosome 2 showed only microsatellite length instability (10%). The degree of genomic instability and its type were independent of tumor type (P > 0.1). We conclude that tumors and tumor cell lines from patients with CC demonstrate significant genomic, but not microsatellite length, instability. Thus, the CC gene(s) on chromosome 2p16 is different from the hMSH2 and hMSH6 genes and has dominant, rather than recessive, tumorigenic function. This gene(s) appears to be involved in the regulation of genomic stability of dividing cells, in particular the structure of telomeres in replicating chromosomes and/or the function of the mitotic apparatus.
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PMID:Cytogenetic and microsatellite alterations in tumors from patients with the syndrome of myxomas, spotty skin pigmentation, and endocrine overactivity (Carney complex). 885 10

We report the results of cytogenetic studies on 23 pituitary adenoma specimens, using both the direct and short-term tissue culture methods. The direct method was applied to all of the specimens and allowed a karyotype to be identified in 15 of the processed samples (65%). Four tumors were shown to have a hypotriploid chromosomal constitution, two of which also presented structural clonal rearrangements: an isochromosome 1q,i(1)(q10) and a der(1)t(1;3)(p22;q21) were observed in two PRL-secreting adenomas, one of which also had a telomeric association involving the short arms of chromosomes 14 and 19. Telomeric associations of the long arms of chromosomes 11, 19, and 22 were observed in a near-diploid, non-secreting tumor showing monosomy 13. One other adenoma showed trisomies 8 and 12, a finding that was confirmed by means of the FISH analysis of chromosome 8 and 12 centromeric probes in the more than 300 scored nuclei. An apparently normal chromosome constitution was observed in the remaining nine cases. Short-term cultures were set up in 21 of the 23 samples, allowing us to obtain a karyotype in 18 specimens (85%). The six tumors that could not be analyzed using the direct method showed a normal karyotype. A diploid chromosome constitution was observed in the four tumors shown to be hypotriploid by the direct method as well as in the tumor with monosomy 13. The trisomies 8 and 12 identified by the direct method in one tumor were still observed, but a clone with a normal karyotype was also found. To the best of our knowledge, this is the only report of the results of cytogenetic studies on pituitary adenomas performed using both direct preparation and short-term culture.
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PMID:Cytogenetic study of pituitary adenomas. 933 78

Telomerase activity is generally absent in primary cell cultures and normal tissues. Telomerase is known to be induced upon immortalization or malignant transformation of human cells. In the present study, we analyzed both telomere length and telomerase activity in biopsy samples from mucosa undergoing metaplasia, adenoma and cancer of the stomach. We attempted to estimate the correlation between telomerase activity and telomere length in these tissues. Telomerase activity was estimated using the telomeric repeat amplification protocol and telomere length by Southern blot analysis. Extracts were defined as telomerase-negative when the signals were less intense than those for 10(2) KATO-III cells (positive control). We detected telomerase activity in 15%, 45% and 89% of the examined cases of intestinal metaplasia, adenoma and gastric cancer respectively. However, telomere length in the gastric mucosa became reduced as the mucosa underwent metaplasia and developed into adenoma. Gastric cancers showed a broad range of telomere length among cases. However, gastric adenomas showed the shortest telomere length. These results suggest that telomerase is expressed during the early phase (intestinal metaplasia through adenoma) of gastric carcinogenesis, although the activity at that stage is not high enough to fully restore the reduced telomeric DNA.
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PMID:Telomere length and telomerase activity in carcinogenesis of the stomach. 937 6

Telomerase activity was examined by telomeric repeat amplification protocol assay in thyroid disease states, including adenomas and carcinomas, and correlated with clinicopathological features. Of a total of 26 papillary carcinomas, 16 cases (61.5%) were positive, with the poorly differentiated subtype being predominant (P < 0.05). A significantly more shortened terminal restriction fragment length (P < 0.05), higher incidence of extrathyroidal extension (P < 0.001), and more elevated Ki-67 labeling indices (P < 0.002) were also found in telomerase-positive than in telomerase-negative papillary carcinomas. Of four follicular carcinomas, 3 cases (75.0%) were positive. Positive telomerase activity in follicular adenomas (9/23 cases, 39.1%) and lymphocytic thyroiditis (12/22 cases, 54.5%) appeared to be mainly caused by infiltrating lymphocytes. However, three cases of atypical adenoma with relatively increased Ki-67 labeling indices were positive, suggesting a possibility of malignant potential. The good correlations with extrathyroidal invasiveness, Ki-67 labeling indices and poor differentiation of papillary carcinomas, established by multivariate analysis, suggest that this parameter might have potential application in the estimation of tumor progression and prognosis, and in clinical management.
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PMID:Significant correlation of telomerase activity in thyroid papillary carcinomas with cell differentiation, proliferation and extrathyroidal extension. 941 58

Human sporadic colorectal adenomas are characterized by a relatively high occurrence of aneuploidy. Similarly, 1p deletions have been reported to be an early event in colorectal tumorigenesis, while chromosome 7, 17 and 18 gain/losses were also found. The present study investigated 1p deletions, the numerical aberrations of chromosomes 1, 7, 17 and 18, and the nuclear DNA content as obtained by flow cytometry in a series of 34 human sporadic colorectal adenomas. From these adenomas, 51 intra-adenoma regions were microdissected according to 2 degrees of dysplasia and presence of foci of early cancer. Isolated epithelial nuclei were analyzed by fluorescence in situ hybridization interphase cytogenetics using centromeric probes for chromosomes 7, 17 and 18 and, in a double-target analysis, a centromeric probe for chromosome 1 simultaneously with a telomeric probe mapping to the 1p36 band. Aneuploidy incidence due to presence of numerical aberrations for at least one among the investigated chromosomes and/or abnormal flow-cytometric DNA content was 35%, while 1p deletion incidence was 38%. The correlation of 1p deletions with aneuploidy was statistically highly significant (p = 0.003), suggesting that loss of genes in this region may be implicated in chromosome instability.
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PMID:Correlation between 1p deletions and aneusomy in human colorectal adenomas. 942 89


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