Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0033036 (APC)
 10,214 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Using single-strand conformation polymorphism we have found two polymorphic sites, AAC to AAT at codon 511 (exon 12) and GCT to GCG at codon 708 (exon 15), in the MCC gene. These sites and an RsaI polymorphic site in APC allowed us to study 23 human small cell lung cancer (SCLC) and 7 non-small cell lung cancer samples for allele loss. Of the 23 SCLC samples, 21 (91%) were informative for one or more of these markers, and we found allele loss in more than 80% (17 of 21). In non-small cell lung cancer samples, 5 of 7 (71%) were informative, and reduction or loss of one allele was found in 2 of 5 (40%). Seven cases were informative for both genes, loss of heterozygosity occurred for both genes in five, one retained heterozygosity for both, and one SCLC had loss of heterozygosity for APC but not for MCC. We conclude that loss of heterozygosity occurs frequently for MCC and APC in lung cancer of all histological types and is very frequent in SCLC. This suggests the presence of tumor suppressor gene(s) in the MCC/APC region of 5q21 involved in human lung cancer.
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PMID:Polymorphic sites within the MCC and APC loci reveal very frequent loss of heterozygosity in human small cell lung cancer. 134 17

We investigated the frequency and clinical significance of loss of heterozygosity (LOH) at the APC, MCC, and DCC tumor suppressor gene loci in 108 cases of resected non-small cell lung cancer (NSCLC). LOH at the APC/MCC gene cluster at chromosome 5q21 occurred frequently; it affected 29% of informative NSCLC cases and correlated with a significantly worse survival (P < 0.01). Furthermore, in the subtype most frequently affected (SCC), LOH at 5q not only correlated with a worse survival but also tumor involvement of the mediastinal and/or hilar nodes. In contrast, LOH at the DCC locus at chromosome 18q was far less frequent, occurring in 14% of NSCLC cases, and it was not associated with advanced stage or prognosis. These data suggest that LOH at 5q has a role in determining tumor progression and survival in NSCLC, and may prove to be a clinically useful prognostic indicator.
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PMID:Tumor progression and loss of heterozygosity at 5q and 18q in non-small cell lung cancer. 781 47

We investigated the clinical implications of allelic deletions at three common sites of loss of heterozygosity (LOH) in regions 5q21, 11p15.5, and 11p13 in 86 patients with non-small cell lung cancer (NSCLC). We performed a PCR-based microsatellite polymorphism assay for detection of LOH. The microsatellite markers used were D5S82 (proximal to the APC gene), MCC (within the MCC gene), D11S904 (11p13), HRAS (within the H-ras gene), and D11S860 (11p15.5). Of the 68 informative cases at 5q21 loci, LOH was found in 14 cases (20%), whereas LOH frequency in 11p15.5 and 11p13 was 31% (19 of 61 informative cases) and 19% (12 of 63 informative cases), respectively. There was a significant correlation between 5q21 LOH and mediastinal lymph node involvement (P = 0.03). However, no differences were observed in median survival times (26 months in patients with 5q21 LOH versus 37 months in the remainder; P = 0.33) nor in patients with 11p LOH (38 months versus 32 months, respectively; P = 0.72). Cox's proportional hazards model predicted that stage was the only independent poor prognostic marker in the entire cohort of NSCLC patients. Thus, the present study revealed two important abnormalities, LOH at chromosome 5q21 and LOH at chromosome 11p, both implied in NSCLC development.
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PMID:Microsatellite alterations at 5q21, 11p13, and 11p15.5 do not predict survival in non-small cell lung cancer. 981 4

Lung cancer is the leading cause of death in both women and men in the United States and many European countries. Molecular cytogenetic and LOH analyses of non-small cell lung cancer have shown somatic genetic alterations in a variety of chromosomes, such as 1p, 3p, 5q, 8p, 9p, 11p, 11q and 17p. Allelic deletions of the known tumor suppressor gene APC at 5q21 are frequently observed in advanced stages of lung cancer and have been correlated with poor prognosis in previous reports. We investigated 33 cases of NSCL for LOH at 5q21: 22 squamous cell and 11 adenocarcinomas. Normal and tumor cells were microdissected from paraffin embedded tissues and PCR amplification was performed utilising the specific markers D5S299 and D5S346 at 5q21 and PYGM at 11q13, respectively. Clinicopathological data, survival and recurrence rates were obtained in all cases. We detected LOH at 5q21 in 4/9 (44%) informative adenocarcinomas and in 13/16 (81%) informative SCC. LOH was frequent in early stages (12/15 stage I cases) and did not correlate with recurrence or poor survival. Our results show that LOH at 5q21 is more frequent in squamous cell carcinomas than in adenocarcinomas, is frequent in early stages of the disease, and does not have prognostic significance.
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PMID:LOH at the APC/MCC gene (5Q21) is frequent in early stages of non-small cell lung cancer. 1054 31

The wealth of data in basic science and translational research may often represent a conundrum for clinical oncologists, who need to selectively consider this abundant information and translate it into therapeutic decisions. For the sake of simplicity, we have classified the multiplicity of genetic abnormalities in five repertoires that are rapidly assessable and useful for stratification in clinical trials: allelic imbalance, aberrant promoter methylation, gene mRNA overexpression, microtubule alterations, and polymorphisms. Allelic imbalance refers to chromosomal instability, which is a major feature of cancer, and innovative techniques used in colorectal cancer should also be implemented in lung cancer. Epigenetic changes (variations in transcription levels) have been extensively studied in non-small cell lung cancer. Methylation techniques have shown that these epigenetic changes commonly occur at the same frequency in numerous genes, both well-known ( FHIT, APC, p16 ) and recently discovered ( TMS1, RASSF1 ) in non-small cell lung cancer and in breast cancer. Innovative techniques like quantitative polymerase chain reaction can determine gene expression profiles, mainly overexpression of mRNAs, which may be related to resistance to specific cytotoxic drugs. In the near future, we hope these profiles can be used to individualize chemotherapy. Multiple microtubule alterations related to overexpression of different genes can also be used to predict response to taxanes and Vinca alkaloids. Finally, the assessment of polymorphisms could enable us to understand their functional consequences in chemotherapy response.
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PMID:Translational oncogenomics: toward rational therapeutic decision-making. 1188 Jul 7

Recent analyses of global and gene-specific methylation patterns in cancer cells have suggested that cancers from different organs demonstrate distinct patterns of CpG island hypermethylation. Although certain CpG islands are frequently methylated in many different kinds of cancer, others are methylated only in specific tumor types. Because distinct patterns of CpG island hypermethylation can be seen in tumors from different organs, it seems likely that histological subtypes of cancer within a given organ may exhibit distinct methylation patterns as well. The goal of our study was to determine whether the patterns of CpG island hypermethylation could be used to distinguish between different histological subtypes of lung cancer. We analyzed the methylation status of 23 loci in 91 lung cancer cell lines using the quantitative real-time PCR method MethyLight. Genes PTGS2 (COX2), CALCA, MTHFR, ESR1, MGMT, MYOD1, and APC showed statistically significant differences in the level of CpG island methylation between small cell lung cancer (SCLC) and non-small cell lung cancer cell lines (NSCLC). Hierarchical clustering using a panel consisting of these seven loci yielded two major groups, one of which contained 78% of the SCLC lines. Within this group, a large cluster consisted almost exclusively of SCLC cell lines. Our results show that DNA methylation patterns differ between NSCLC and SCLC cell lines and suggest that these patterns could be developed into a powerful molecular marker to achieve accurate diagnosis of lung cancer.
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PMID:Hierarchical clustering of lung cancer cell lines using DNA methylation markers. 1189 80

In the present study, we used 22 microsatellite markers flanking to or within 13 known or candidate tumor suppressor genes (TSGs) to detect loss of heterozygosity (LOH) in these chromosomal regions among 41 cases of non-small cell lung cancer, including 28 squamous cell carcinoma (SCC) and 13 adenocarcinoma (ADC). The studied TSGs comprised FHIT, VHL, APC, PRLTS, p16, IFNA, PTEN, p57, ATM, p53, BRCA1, DPC4 and DCC. Our data demonstrated frequent allelic losses of FHIT, p53, IFNA, VHL and p16 in both SCC and ADC. PTEN and ATM showed the least frequency of LOH, while no deletion of BRCA1 was detected in all tumor samples. LOH analysis of PRLTS was extended to 26 cases of ADC, which demonstrated significantly higher frequency of LOH than SCC. Our data indicated a possible correlation between specific TSG(s) and either histological type of lung cancer, and more attention should be paid to the PRLTS gene, which might play an important role in the development of ADC.
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PMID:Deletion of tumor suppressor genes in Chinese non-small cell lung cancer. 1212 91

Aberrant methylation of several known or putative tumor suppressor genes occurs frequently during the pathogenesis of lung cancers. There are major smoke exposure, histology, geography and gender-related changes in non-small cell lung cancer (NSCLC). We investigated smoking-related, histologic, geographic and gender differences in the methylation profiles of resected NSCLCs. We examined 514 cases of NSCLC and 84 corresponding nonmalignant lung tissues from 4 countries (USA, Australia, Japan and Taiwan) for the methylation status of 7 genes known to be frequently methylated in lung cancers [p16, RASSF1A (RAS association domain family 1), APC, RARbeta, CDH13, MGMT and GSTP1]. Multivariate analyses were used for data analysis. Adenocarcinoma was the major histologic type in women and never smokers; analyses that involved smoke exposure and gender were limited to this histology. Our major findings are a) methylation status of any single gene was largely independent of methylation status of other genes; b) the rates of methylation of p16 and APC and the mean Methylation Index (MI), a reflection of the overall methylation status, were significantly higher in ever smokers than in never smokers; c) the mean MI of tumors arising in former smokers was significantly lower than the mean of current smokers; d) the methylation rates of APC, CDH13 and RARbeta were significantly higher in adenocarcinomas than in squamous cell carcinomas; e) methylation rates of MGMT and GSTP1 were significantly higher in the USA and Australian cases than in those from Japan and Taiwan; and (f) no significant gender-related differences in methylation patterns were noted. Our findings demonstrate important smoke exposure, histologic type and geography-related differences in the methylation profiles of NSCLC tumors.
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PMID:Smoke exposure, histologic type and geography-related differences in the methylation profiles of non-small cell lung cancer. 1245 28

Aberrant methylation of promoter CpG islands is known to be a major inactivation mechanism of tumor suppressor and tumor-related genes. To determine the clinicopathological significance of gene promoter methylation in non-small cell lung cancer (NSCLC), we examined the promoter methylation status of the APC, DAP-kinase, E-cadherin, GSTP1, hMLH1, p16, RASSF1A and RUNX3 genes in 75 NSCLCs and corresponding non-neoplastic lung tissues by methylation-specific PCR (MSP). The frequencies of methylation in NSCLCs and corresponding non-neoplastic lung tissues were: 37% (28 of 75) and 48% (36 of 75) for APC, 28% (21 of 75) and 13% (10 of 75) for DAP-kinase, 29% (22 of 75) and 15% (11 of 75) for E-cadherin, 1% (1 of 75) and 0% (0 of 75) for GSTP1, 7% (5 of 75) and 0% (0 of 75) for hMLH1, 31% (23 of 75) and 0% (0 of 75) for p16, 43% (32 of 75) and 4% (3 of 75) for RASSF1A, and 20% (15 of 75) and 3% (2 of 75) for RUNX3, respectively. Methylation of p16 was more frequent in squamous cell carcinomas than in adenocarcinomas (P < 0.05), and was associated with tobacco smoking (P < 0.05). On the contrary, methylation of APC and RUNX3 was more frequent in adenocarcinomas than in squamous cell carcinomas (P < 0.05). Thus, a different set of genes is thought to undergo promoter methylation, which leads to the development of different histologies. In addition, methylation of p16, RASSF1A and RUNX3 was mostly cancer-specific (P < 0.05), and may be utilized as a molecular diagnostic marker of NSCLCs.
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PMID:Promoter hypermethylation of tumor suppressor and tumor-related genes in non-small cell lung cancers. 1284 66

A prospective screening program, including CT, autofluorescent bronchoscopy, biopsies and bronchial lavage (BL) collection, was initiated with the specific goal of identifying biomarkers for the early detection of non-small cell lung cancer. We report and discuss the results of p16, DAPK, MGMT, FHIT and APC methylation analysis in the 126 first patients: 77 at high risk of cancer and 49 followed up after primary cancer resection. Positive results were found in 49% of BLs, 53% in current smokers and 43% in former smokers. In presence of peripheral tumours, only 38% of BLs were abnormal versus 73% in presence of central tumours, 50% in presence of preneoplasic lesions and 47% in absence of lesions. FHIT methylation was an early event, observed in one-third of the BLs from patients with or without lesions as well as in tumours. APC methylation was a late event observed in 33% of tumours but rarely in BLs. p16 was methylated in 17% of BLs but in 48% of tumours; DAPK in 15% of BL and 22% of tumours. MGMT methylation was rare. Among patients followed up after cancer surgery, 14 were in remission with normalised BL, whereas three had positive BLs and relapsed with a central tumour. Thus, gene methylation in BL might help to detect central tumours but a CT is crucial for peripheral cancer detection.
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PMID:Promoter methylation of genes in bronchial lavages: a marker for early diagnosis of primary and relapsing non-small cell lung cancer? 1604 58


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