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)

The MTS1/CDK4I gene encodes a 16 kDa cyclin kinase inhibitor and maps to chromosome 9p21. Previous studies have suggested the presence of a major tumour suppressor gene at this locus which may be inactivated in head and neck squamous cell carcinoma (HNSCC). To determine the status of this gene in human primary and metastatic HNSCC, we examined the locus and its transcript for abnormalities by polymerase chain reaction (PCR). Out of 14 cell lines studied, four had lost only exon 1, one had lost only exon 2, three had lost both exons 1 and 2, and none of the remaining six lines expressed a normal p16 mRNA. These latter six cell lines expressed p16 transcripts that had suffered deletions ranging in size from 2-16 base pairs. In each case, deletions led to a change of reading frame. Furthermore, in two cases abnormalities in the MTS1/CDK4I gene were identical in cells derived from metastatic tumours as compared to cells derived independently from the corresponding primary tumour. The identical nature of mutations observed in primary tumours and metastases derived from the same patient provides strong evidence that inactivation of p16 function was an in vivo event.
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PMID:MTS1/CDK4I is altered in cell lines derived from primary and metastatic oral squamous cell carcinoma. 800 Dec 21

We have examined the presence of p16MTS1/CDK4I gene deletions, mutations and methylation status, and 9p21-23 deletions in a series of 46 squamous cell carcinomas of the larynx and paired normal mucosa previously characterized for cyclin D1 gene amplification and overexpression. pRb expression was also examined by immunohistochemistry. p16MTS1/CDK4I mutations were found in 10/46 (22%) carcinomas and hypermethylation in 2/31 (7%). Loss of heterozygosity at 9p21-23 was found in 24 out of 42 (57%) carcinomas examined. All p16MTS1/CDK4I mutated cases and the two hypermethylated carcinomas showed 9p21-23 loss of heterozygosity. The loss of heterozygosity correlated with advanced local invasion (P=0.0045), lymph node metastases (P=0.0326), stage IV of the tumors (P=0.0058), and existence of cyclin D1 amplification/overexpression (P < 0.03). Only one out of 37 carcinomas was negative for pRb expression. No alterations in p16 gene or 9p21-23 loss of heterozygosity were detected in this case. These findings indicate that p16MTS1/CDK4I is frequently inactivated by gene mutation, hypermethylation, and allelic deletions in a significant subset of squamous cell carcinomas of larynx. Since 9p21-23 loss of heterozygosity was more frequently detected than p16MTS1/CDK4I mutations, and mutated carcinomas invariably had loss of heterozygosity, allelic losses probably precede the p16MTS1/CDK4I mutations. Their association with cyclin D1 deregulation in advanced carcinomas could indicate a possible cooperative effect in the progression of these neoplasms.
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PMID:p16MTS1/CDK4I mutations and concomitant loss of heterozygosity at 9p21-23 are frequent events in squamous cell carcinoma of the larynx. 933 20