Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0596263 (carcinogenesis)
 64,820 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

nm23H1 has properties of a metastasis suppressor gene. Although its mechanism of action is unknown, nm23 has been implicated in transforming growth factor beta 1 (TGF beta 1) signal transduction. In an earlier study we decreased nm23 mRNA levels 2- to 8-fold by antisense phosphorothiolated oligonucleotides in two HT29 colon carcinoma sublines at different stages in tumor progression with different responses to TGF beta 1: the HD3 subline, which shows TGF beta 1-induced growth arrest and differentiation; and the more tumorigenic U9 subline, whose growth and invasion are stimulated by TGF beta 1. Only TGF beta 1-mediated responses in HD3 cells were inhibited by nm23 antisense oligos, suggesting that nm23 functions in only one TGF beta 1 signaling pathway. In the current report we have extended this study to cell motility. HD3 motility was increased by nm23 phosphorothiolated antisense oligos which decrease nm23 mRNA levels, while HD3 cell motility was conversely decreased by TGF beta 1 which increases nm23 mRNA levels. HD3 motility was not increased by basic FGF, TGF beta 1 or TGF alpha, while the 13-fold higher basal motility of U9 cells was stimulated 3-fold by basic FGF, 4-fold by TGF beta 1 and 5-fold by TGF alpha, but not by scatter factor. Differences in motility and response to motility factors could not be ascribed to differences in either basal levels of proteases or modulation of their levels by TGF beta 1. Both HD3 and U9 cells displayed equal levels of urokinase activity and mRNA, equal expression of the metalloproteinase inhibitor TIMP-1, and no detectable collagenases by zymography. No differential response to TGF beta 1 was seen in any of these assays. Thus limited cell motility and lack of response to motility factors in HD3 colon cancer cells could be correlated with expression of nm23 active in signal transduction.
Carcinogenesis 1995 Sep
PMID:Colon carcinoma cells with inactive nm23 show increased motility and response to motility factors. 755 87

The nm23-H1 gene has been proposed as a metastasis suppressor gene. It is located on the long arm of chromosome 17, which is frequently deleted in ovarian cancer, and shows altered expression and structure in some advanced neoplasms. To evaluate the role of nm23-H1 in ovarian carcinogenesis, we have analyzed this gene in 66 primary human ovarian carcinomas at both the DNA and RNA levels. Despite the high frequency (76%) of nm23-H1 loss of heterozygosity (LOH), the complete absence of gene mutations in the coding portions of the retained allele clearly indicated that, in ovarian carcinomas, this gene does not function in the same way as do classic oncosuppressor genes. The relationship of clinicopathological parameters with nm23-H1 gene deletions and expression levels was also investigated. LOHs were more common in the serous and endometrioid histotypes (85 and 93%, respectively), and the highest LOH frequency was detected in poorly differentiated tumors (89%). A significant relationship between nm23-H1 mRNA expression and lymph node metastasis was observed in high-grade tumors, which are intrinsically more invasive than are low-grade tumors. In particular, among the poorly differentiated tumors showing areas of undifferentiated solid carcinoma (classified as G3/G4), lymph node-negative tumors displayed expression levels that were significantly higher than those of lymph node-positive tumors (P < 0.001). In conclusion, our data suggest that the nm23-H1 gene product may exert an inhibitory effect on the lymphatic dissemination of human ovarian tumors. However, several other factors, biological or time and patient dependent, influence the complex metastatic progression of ovarian tumors and may cooperate with nm23-H1 in the promotion or inhibition of this process.
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PMID:Suppressive role of the metastasis-related nm23-H1 gene in human ovarian carcinomas: association of high messenger RNA expression with lack of lymph node metastasis. 778 Sep 79

The NM23-H1 gene product has been recently identified as a potential metastasis suppressor. Studies on breast carcinomas have shown an inverse correlation between NM23-H1 status and stage of carcinogenesis and overall survival. However, in colorectal cancer, conflicting data have been reported. This study aimed to investigate whether NM23-H1 immunostaining is correlated with tumour stage, overall survival, disease recurrence, tumour differentiation, age and sex in colorectal carcinomas for the Singapore population using chi-square analysis. The staining was performed on 141 paraffin-embedded surgical specimens collected between 1991 and 1992 using a monoclonal anti-NM23-H1 antibody. Follow-up of patients was until time of death or for 5 years. There was a very significant inverse association between tumour staging and NM23-H1 status (P = 0.0004). However, NM23-H1 expression was not significantly correlated to overall 5-year survival, disease recurrence, tumour differentiation, age or sex. Thus, although NM23-H1 may be involved in suppressing metastasis, NM23-H1 immunohistochemistry has no prognostic value in colorectal cancer. This is the first report of a significant inverse association of NM23-H1 status with tumour staging in colorectal cancer which showed no correlation with overall survival or disease recurrence. Our result thus cautions against the practice of equating an inverse relation of genetic markers with tumour staging to survival or disease recurrence.
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PMID:NM23-H1 immunostaining is inversely associated with tumour staging but not overall survival or disease recurrence in colorectal carcinomas. 956 56

The nm23 gene was initially cloned as a metastasis suppressor gene, but the clinical relevance of nm23-H1 as a metastasis suppressor or prognostic indicator for human cancers remains enigmatic. Given that gene expression is regulated at the tissue-specific level, we studied the molecular mechanisms of nm23-H1 expression in human bladder cancer cell lines and the clinical importance of protein product (NM23-H1) in association with patient outcome (n = 257) by immunohistochemistry. We demonstrated that nm23-H1 is expressed in bladder cancer cells without genomic alterations. High NM23-H1 expression was found in 39 cases (15.2%), intermediate expression in 119 cases (46.3%), and low NM23-H1 in 99 cases (38.5%). NM23-H1 was inversely related to staging classification or tumor size (P < 0.05), with the most significant difference being observed between pTa tumors and those of pT1-pT3 bladder cancer (P = 0.01). Reduced NM23-H1, defined as intermediate and low levels of expression, tended to have a higher risk of tumor metastasis (P = 0.06) or poor longtime survival (P = 0.07). In the subset of grade 2 bladder tumors, reduced NM23-H1 significantly correlated with the occurrence of tumor metastasis or poor patient survival (P < 0.05). These findings overall suggest that nm23-H1 may play an important role in suppressing the early step of carcinogenesis and thus act as an invasion suppressor for human bladder cancer. A prospective study is required to clarify the potential of the molecular marker in prediction of disease progression.
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PMID:The role of nm23-H1 in the progression of transitional cell bladder cancer. 1099 50

Reduced expression of the metastasis suppressor gene nm23-H1 has been previously correlated with high tumor metastatic potential and fatal clinical outcome in several types of human carcinomas. The aim of the study was to identify the expression of nm23-H1 in a variety of premalignant and malignant cervical lesions. The study comprised 106 cervical biopsies obtained from 106 women ranging in age from 23 to 68 (median 42) years. Histologic slides stained with H&E were evaluated blindly by two pathologists and a consensus diagnosis was established for each case. In addition, immunohistochemical stain was employed and a monoclonal antibody against nm23-H1 (YLEM Rome, Italy) was used. Twenty-five of the cervical biopsies showed changes of mild dysplasia (CIN I), whereas 28 demonstrated features of moderate dysplasia (CIN II) and 28 severe dysplasia (CIN III). In 25 cases infiltrating squamous cell carcinoma was identified. Expression of nm23-H1 was evident in 9/25 (36%) CIN I, 13/28 (46%) CIN II, 22/28 (78.5%) CIN III and 17/25 (68%) infiltrating carcinoma biopsies. Statistically significant differences were observed between CIN II and CIN III (p=0.003), and CIN II and infiltrating carcinoma (p=0.002) groups. Expression of the nm23-H1 gene in premalignant and malignant cervical lesions indicates that this gene may play a substantial role in carcinogenesis and tumor progression.
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PMID:Immunohistochemical analysis of nm23-H1 expression in human cervical lesions. 1119 46

The importance of altered histone acetylation in gastrointestinal carcinogenesis, especially in relation to invasion and metastasis, is described. Histone acetylation and chromatin remodeling linked with CpG island methylation play a major role in epigenetic regulation of gene expression. Acetylation of histones through an imbalance of histone acetyltransferases and deacetylases disrupts nucleosome structure, which leads to DNA relaxation and subsequent increase in accessibility to transcription factors. The expression of acetylated histone H4 is reduced in a majority of gastric and colorectal cancers, indicating the low level of global histone acetylation in tumor cells. Moreover, reduced histone acetylation is significantly associated with depth of tumor invasion and nodal metastasis of gastrointestinal cancers. A histone deacetylase inhibitor, trichostatin A (TSA), induces growth arrest and apoptosis and suppresses invasion of cancer cells. Treatment with TSA, which is followed by increased histone acetylation in the promoters, induces the expression of many genes that are suppressors of invasion and metastasis, including tissue inhibitors of metalloproteinase and nm23H1/H2, in addition to negative cell cycle regulators and apoptosis-related molecules. Our approach, serial analysis of gene expression (SAGE), enabled us to identify a gene that is a novel candidate for a metastasis suppressor, whose expression is induced by histone acetylation. These findings suggest that, by modifying gene expression, histone deacetylation may participate not only in tumorigenesis but also in invasion and metastasis. Therefore, histone acetylation should be a promising target for cancer therapy, especially against invasive and metastatic disease, but also for cancer prevention.
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PMID:Histone acetylation and gastrointestinal carcinogenesis. 1272 27

It is now widely accepted that human carcinogenesis is a multi-step process and phenotypic changes during cancer progression reflect the sequential accumulation of genetic alterations in cells. Thus, in order to understand the process of acquisition of metastatic phenotypes in cancer cells, it is indispensable to identify genes whose alterations accumulate during cancer progression and correlate with metastatic phenotypes of cancer cells. For this reason, we have been searching for genes that are preferentially altered in metastatic lung cancer cells and have activities to regulate their metastatic potentials. In lung cancer, both the p16INK4A/RB and p53 genes are frequently inactivated and are critical determinants for the regulation of cell growth and apoptosis. However, it still remains unclear whether these genes are also involved in the regulation of metastatic potential in lung cancer cells. Recently, we identified a novel myosin family gene, MYO18B, from the chromosome 22q12.1 region which shows frequent loss of heterozygosity in advanced lung cancer, and we found that this gene is inactivated in approximately 50% of lung cancers by deletions, mutations and methylation. Furthermore, restoration of MYO18B expression suppressed anchorage-independent growth of lung cancer cells. Thus, it was indicated that the MYO18B gene is a strong candidate for a metastasis suppressor gene of human lung cancer. Further functional and biological studies of the MYO18B gene will help us understand the molecular pathway of human lung cancer progression.
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PMID:Genetic alterations responsible for metastatic phenotypes of lung cancer cells. 1274 77

The multistep process of carcinogenesis implies the accumulation of multiple molecular defects. Alteration of tumor suppressor and metastasis suppressor genes are the important steps. Increasing experimental evidence indicates that decreased expression of tumor-metastasis/suppressor genes and gene products are involved in the progression of a variety of human malignancies. In the present study, we have extended this analysis to non-small cell lung carcinomas (NSCLC). The expression and prognostic significance of the tumor suppressor gene PTEN and metastasis suppressor genes nm23-H1 and KAI-1 was evaluated in NSCLCs. Immunohistochemical staining was performed on formalin-fixed, paraffin-embedded tissues from 53 bronchogenic adenocarcinomas and 51 squamous cell carcinomas using monoclonal antibodies against PTEN, nm23H-1, and KAI-1 proteins. Immunohistochemical results were correlated with tumor stage, grade, lymph nodes positivity, metastasis, and patient survival. Significant co-expression of PTEN, nm23-H1 and KAI-1 was observed in NSCLC (P<.001 to .002). The immunohistochemical expression of these proteins was significantly higher in stages 1 and 2 compared with stages 3 and 4 (P=.04 for PTEN and KAI-1, P=.039 for nm23-H1). When all stages were considered together, loss of immunoreactivity for PTEN, nm23-H1 and KAI-1 was found in advanced NCSCLs (P=.015 for PTEN, P=.001 for KAI-1, P=.004 for nm23-H1), which is suggestive of co-downregulation of these proteins in the process of tumor progression. On multivariate analysis, negative staining for PTEN (P=.014), KAI-1 (P=.034), and nm23-H1 (a trend toward association for nm23-H1 reached near significance P=.08) correlated with disease-related death. Positive lymph node status was associated with negative immunostaining for PTEN (P=.007) but no correlation was observed for nm23-H1 and KAI-1. Loss of expression was linked to distant metastasis (P=.006 for PTEN, P=.002 for nm23H1, P=.001 for KAI-1). On multivariate analysis, co-downregulation of PTEN (P=.009), KAI-1 (P=.02), and nm23-H1 (P=.011) independently predicted shortened survival in NSCLC. Although NSCLC exhibits strong co-expression of PTEN, nm23-H1 and KAI-1, there is a loss of these proteins in high-stage tumors. Co-downregulation of PTEN, KAI-1, and nm23-H1 significantly correlates with distant metastasis and predicts shortened survival. Our study supports a role of these tumor suppressor and metastasis suppressor genes in the evolution and progression of NSCLC.
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PMID:Co-downregulation of PTEN, KAI-1, and nm23-H1 tumor/metastasis suppressor proteins in non-small cell lung cancer. 1512 4

CD82 (KAI1) and CD63 (ME491) are highly glycosylated proteins which belong to the transmembrane 4 superfamily (TM4SF). CD82 has been implicated as a possible prostate cancer metastasis suppressor gene, whereas CD63 is involved in the progression of human melanoma cancer. Down-regulation of both CD82 and CD63 expression has been associated with the metastatic potential of several solid tumors. Currently, information is lacking on the role of CD82 and CD63 during thyroid carcinogenesis. The aim of this study was to determine whether the expression of CD82 and CD63 is a useful prognostic indicator in patients with thyroid carcinoma. The expression of CD82 and CD63 was analysed by reverse transcriptase-PCR (RT-PCR) and immunohistochemistry in benign goiter (n=12) and 75 primary thyroid carcinoma tissue specimens (PTC: 33, FTC: 24, UTC: 18) out of which 36 were non-metastasized primary tumors and 39 were metastasized tumors (regional lymph node and/or distant metastases). All of the benign goiter tissues showed CD82 expression. By contrast, a significant decrease in CD82 mRNA and protein levels was detected in carcinoma tissues as compared to benign goiter tissues (p<0.001). A similar down-regulation was observed in metastasized tumor tissues when compared with non-metastasized tumors (all p<0.05). CD82 expression was correlated with pTNM status of differentiated and undifferentiated thyroid tumor and the pathologic stage of differentiated thyroid tumor. In contrast to CD82, CD63 mRNA and protein expression was unchanged in all thyroid carcinomas. Benign goiter tissues showed weak expression of CD63. There were no significant correlation between CD63 mRNA/protein expression and any clinical/pathological parameters. Our results support the hypothesis that down-regulation of CD82 expression may reflect an increased in vivo metastatic potential of thyroid cancer cells. CD82 may serve as a prognostic marker of metastasis in thyroid cancer. Constitutive expression of CD63 may indicate that this factor does not play a direct role in thyroid carcinogenesis.
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PMID:CD82, and CD63 in thyroid cancer. 1537 77

To identify novel methylation-silenced genes in gastric cancers, we carried out a chemical genomic screening, a genome-wide search for genes upregulated by treatment with a demethylating agent, 5-aza-2'-deoxycytidine (5-aza-dC). After 5-aza-dC treatment of a gastric cancer cell line (AGS) 579 genes were upregulated 16-fold or more, using an oligonucleotide microarray with 39,000 genes. From these genes, we selected 44 known genes on autosomes whose silencing in gastric cancer has not been reported. Thirty-two of these had CpG islands (CGI) in their putative promoter regions, and all of the CGI were methylated in AGS, giving an estimated number of 421+/-75 (95% confidence interval) methylation-silenced genes. Additionally, we analyzed the methylation status of 16 potential tumor-related genes with promoter CGI that were upregulated four-fold or more, and 14 of these were methylated in AGS. Methylation status of the 32 randomly selected and 16 potential tumor-related genes was analyzed in 10 primary gastric cancers, and 42 genes (ABHD9, ADFP, ALDH1A3, ANXA5, AREG, BDNF, BMP7, CAV1, CDH2, CLDN3, CTSL, EEF1A2, F2R, FADS1, FSD1, FST, FYN, GPR54, GREM1, IGFBP3, IGFBP7, IRS2, KISS1, MARK1, MLF1, MSX1, MTSS1, NT5E, PAX6, PLAGL1, PLAU, PPIC, RBP4, RORA, SCRN1, TBX3, TFAP2C, TNFSF9, ULBP2, WIF1, ZNF177 and ZNF559) were methylated in at least one primary gastric cancer. A metastasis suppressor gene, MTSS1, was located in a genomic region with frequent loss of heterozygosity (8q22), and was expressed abundantly in the normal gastric mucosa, suggesting its role in gastric carcinogenesis. (Cancer Sci 2006; 97: 64 -71).
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PMID:Chemical genomic screening for methylation-silenced genes in gastric cancer cell lines using 5-aza-2'-deoxycytidine treatment and oligonucleotide microarray. 1636 23


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