Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human basal cell cancer (BCC) shows unique growth characteristics, including a virtual inability to metastasize, absence of a precursor stage and lack of tumour progression. The clonal nature of BCC has long been a subject for debate because of the tumour growth pattern. Despite a morphologically multifocal appearance, genetic analysis and three-dimensional reconstructions of tumours have favoured a unicellular origin. We have utilized the X-chromosome inactivation assay in order to examine clonality in 13 cases of BCC. Four parts of each individual tumour plus isolated samples of stroma were analysed following laser-assisted microdissection. In 12/13 tumours, the epithelial component of the tumour showed a monoclonal pattern suggesting a unicellular origin. Surprisingly, one tumour showed evidence of being composed of at least two non-related monoclonal clones. This finding was supported by the analysis of the ptch and p53 gene. Clonality analysis of tumour stroma showed both mono- and polyclonal patterns. A prerequisite for this assay is that the extent of skewing is determined and compensated for in each case. Owing to the mosaic pattern of normal human epidermis, accurate coefficients are difficult to obtain; we, therefore, performed all analyses both with and without considering skewing. This study concludes that BCC are monoclonal neoplastic growths of epithelial cells, embedded in a connective tissue stroma at least in part of polyclonal origin. The study results show that what appears to be one tumour may occasionally constitute two or more independent tumours intermingled or adjacent to each other, possibly reflecting a local predisposition to malignant transformation.
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PMID:Genetic mosaicism in basal cell carcinoma. 1602 81

Sclerosing polycystic adenosis (SPA) is a recently described, rare lesion of the salivary glands that bears a resemblance to epithelial proliferative lesions of the breast. The true nature of the lesion is unknown, but up to now it has been generally believed to represent a pseudoneoplastic sclerosing and inflammatory process. However, local recurrence developed in about one-third of the cases. Superimposed dysplastic changes ranging from low-grade dysplasia to carcinoma in situ were described in SPA. Although no metastases-related and/or disease-related patient deaths were documented, these clinical and histopathologic features raise the possibility that SPA might represent a neoplastic lesion. Polymorphism of the human androgen receptor locus is most frequently used to assess whether the pattern of X-chromosome inactivation is random or nonrandom, the latter strongly indicating clonality. In this study, the assay was applied to tissue from 12 examples of SPA. Three cases (males) were noninformative and 3 cases (females) could not be analyzed owing to poor quality of DNA, but all the remaining 6 lesions satisfied the criteria for monoclonality. We therefore conclude that the findings in the present study are further supporting evidence that SPA is a neoplasm, and not just a reactive process.
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PMID:Clonal nature of sclerosing polycystic adenosis of salivary glands demonstrated by using the polymorphism of the human androgen receptor (HUMARA) locus as a marker. 1686 63

Loss of heterozygosity (LOH) has previously been demonstrated at multiple chromosome microsatellites in primary and metastatic melanomas. Epidermotropic metastases of melanoma are unique in their varied histopathologic appearance, which can mimic a primary lesion. Our objective was to compare LOH profiles in primary and epidermotropic metastatic melanoma to delineate their clonal relationship. We examined the pattern of allelic loss in the primary melanomas of nine patients in addition to the 21 corresponding epidermotropic metastatic melanomas (average 2.3 metastases per patient). DNA samples were prepared from formalin-fixed, paraffin-embedded tissue sections using laser capture microdissection. Eight DNA microsatellite markers on six different chromosomes were analyzed: D1S214 (1p), D6S305 (6q), D9S171 (9p), D9S157 (9p), IFNA (9p), D10S212 (10q), D11S258 (11q), D18S70 (18q). In addition, X-chromosome inactivation analysis was performed in tumors from four women. LOH was seen in 67% (6/9) of primary melanomas and 81% (17/21) of epidermotropic metastatic melanomas. The most frequent allelic losses in informative cases occurred at 10q (33%), 9p (22%), and 11q (22%) in primary melanomas, and at 10q (50%), 1p (44%), and 6q (39%) in epidermotropic metastatic melanomas. Primary lesions demonstrating LOH had concordant allelic loss in at least one locus in a corresponding epidermotropic metastatic melanoma in 83% (5/6) of cases. X-chromosome analysis showed nonrandom inactivation in 75% (3/4) and 71% (5/7) of primary melanoma and epidermotropic metastatic melanoma cases, respectively. Our LOH and X-chromosome inactivation analysis data suggest that epidermotropically metastatic melanomas are clonally related to their primary lesion in many cases. Our data also indicated that some cases diagnosed as epidermotropic metastatic melanoma might be divergent clones or new primaries rather than metastatic disease.
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PMID:Clonal relationships between epidermotropic metastatic melanomas and their primary lesions: a loss of heterozygosity and X-chromosome inactivation-based analysis. 1757 Oct 79

Melanoma of the skin frequently metastasizes to multiple regional lymph nodes and to distant sites. It is uncertain whether all metastases originate from the same tumor clone or whether the genetic heterogeneity of the primary tumor is reflected in the multiple metastases. A total of 73 archival, formalin-fixed, paraffin-embedded, melanoma lesions, including 13 primary tumors and 60 metastases, were studied from 13 patients each having 2 or more metastatic tumors. Genomic DNA samples were prepared from tissue sections using laser-assisted microdissection. We find that the majority of melanoma metastases share a common clonal origin with the matched primary tumor. However, significant genetic divergence occurs frequently during the clonal evolution of metastatic melanoma. In addition, using X-chromosome inactivation analysis, we find that, in some cases, multiple coexisting metastases seem to be derived from different, genetically unrelated tumor clones, implying that some primary tumors may arise from more than a single transformed melanocyte.
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PMID:Genetically heterogeneous and clonally unrelated metastases may arise in patients with cutaneous melanoma. 1759 69

Malignant peripheral nerve sheath tumors (MPNSTs) develop in patients with underlying NF1, and usually arise as a result of malignant transformation of a pre-existing plexiform neurofibroma. The clonal cytogenetic abnormalities reported in primary MPNST include complex karyotypes with chromosome numbers in the triploid or tetraploid range with recurrent abnormalities of several chromosomes including losses or imbalances. As a prelude to cell biological, pharmacological, and functional studies to investigate pathways and gene(s) associated with multistep tumorigenesis, which includes progression, metastasis and resistance to therapy in MPNST, detailed molecular cytogenetic and genetic analyses of cell lines from primary, metastatic and recurrent MPNST with underlying NF1 disorder have been performed. The clonal cytogenetic abnormalities detected in the primary tumor cell line were similar to those observed in primary cultures of this tumor. Due to the complexity of the rearrangements seen by G-banded karyotype analysis, further characterization of the clonal abnormalities in these three cell lines was performed by molecular cytogenetic techniques, including CGH and SKY. CGH analysis detected recurrent deletions of 9p, 12q21-q32, complete losses of the X-chromosome, and gains of the chromosomal segment 17q25 in all three cell lines. SKY analysis detected extensive clonal abnormalities in these cell lines. The nature and the alterations of the cell cycle regulators, particularly those associated with G1-S checkpoints and known to be deregulated in MPNST, were studied. These cell cycle regulators included those associated with Rb1-cyclin D1 and the p53 pathways. The findings are consistent with the argument that an imbalance between the cyclin activators of CDKs and inhibitory proteins such as p16 result in uncontrollable proliferation in the cell lines, associated with progression of the disease. LOH and expression of the p53 gene in metastatic and recurrent cell lines was observed, as reported by others. The role of biallelic inactivation of p53 gene in MPNST with underlying NF1 mutations, however, needs further study. Overexpression of Rb1-protein observed in metastatic and recurrent cell lines is indicative of its role in the progression of the disease. One of the most important observations of this study is that Nm23-H1 expression is closely associated with advanced or metastatic disease. In summary, MPNST cell lines derived from a patient with metastatic and recurrent disease with NF1 disorder were characterized and a gene associated with metastatic potential which is amenable to therapeutic and chemo-preventative approaches was identified. These cell lines with extensive characterization of genetic abnormalities are likely to provide important reagents for biochemical, molecular and pharmacological studies related to MPNST.
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PMID:Molecular characterization of permanent cell lines from primary, metastatic and recurrent malignant peripheral nerve sheath tumors (MPNST) with underlying neurofibromatosis-1. 1941 72

We report a very rare case of combined thymic carcinomas: undifferentiated thymic carcinoma coexisting with type AB thymoma. The precise mechanism underlying the coexistence of these tumors remains unknown. Therefore, we used clonality analysis to ascertain whether the two tumors were clonally related. A 63-year-old woman with thyroid cancer visited our hospital. Chest computed tomography also revealed an anterior mediastinal tumor. The patient was treated with total thyroidectomy and surgery for mediastinal tumors together with left upper lobe partial resection. The mediastinal tumor was pathologically diagnosed as undifferentiated thymic carcinoma coexisting with type AB thymoma. Multiple pulmonary metastases were detected in the patient and stage IV disease was diagnosed. The tumor was treatment-resistant, and the patient received fourth-line chemotherapy. We conducted clonality analysis using an improved human androgen receptor gene-amplification assay that involves random X-chromosome inactivation through methylation, followed by methylated gene-specific PCR amplification after sample DNA digestion with HpaII, a methylation-sensitive restriction enzyme. Clonality analysis demonstrated identical X-chromosome inactivation in cells present in both thymoma and thymic carcinoma areas, and thus revealed clonal proliferation. The two lesions in the patient might have arisen through the transformation of a preexisting thymoma into a more malignant lesion.
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PMID:Clonality analysis performed using human androgen receptor assay in a rare case of undifferentiated thymic carcinoma coexisting with type AB thymoma. 2732 90


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