Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Both hyaluronan and one of its receptors, CD44, can be demonstrated in the early human conceptus and in placental stroma. The variants of CD44 resulting from variable exon splicing are found in metastasizing human malignancies and are also involved in hyaluronan uptake and degradation. The resulting hyaluronan fragments are known to be highly angiogenic. We postulated that the self-limited process of trophoblast invasion of the uterine decidua results in part from the strategy of alternative splicing of CD44, similar to that used by invasive cancer cells in the course of metastatic spread and possibly angiogenesis. Monoclonal antibodies specific for CD44s and for an exon expressed during metastatic tumour progression, CD44v7, were used to examine this hypothesis. In this study we found human trophoblasts, for the first time, to express CD44. Intermediate trophoblasts of first and second trimester exhibited the standard form of CD44 while extravillous trophoblasts, which are responsible for the invading characteristics of the placenta, were positive for the alternatively spliced form, the CD44v7-8. Moreover, in the case of placenta accreta there was a prominent membrane staining of the trophoblasts that were embedded in the fibrin layer over the myometrium. The highly metastatic choriocarcinoma cells also expressed CD44v7-8. We propose, therefore, that the invading trophoblasts utilize the alternatively splicing machinery. These cells retain their invasive capabilities through the permissive ECM by carrying the CD44v7-8 isoform, which binds weakly to hyaluronan and thus prevents it from being degraded by intracellular hyaluronidase.
Mol Hum Reprod 1996 Sep
PMID:Hyaluronan, CD44 and its variant exons in human trophoblast invasion and placental angiogenesis. 923 83

To better understand the mechanism(s) underlying lung cancer invasion and metastasis, a Transwell invasion chamber was used to select progressively more invasive cancer cell populations from a clonal cell line of human lung adenocarcinoma, CL1. Five sublines with progressive invasiveness, designated CL1-1, CL1-2, CL1-3, CL1-4, and CL1-5, were obtained through this in vitro selection process. Their invasive abilities through basement membrane matrix showed a 4- to 6-fold increase over that of the parental cells. Moreover, the sublines manifested an increase in their colony-forming ability on soft agar, tumorigenicity, and metastatic potency in severe combined immunodeficiency (SCID) mice. Examining the phenotypes of the cell lines revealed increased expression of 92 kD gelatinase and an increase in the cell population stained with anti-keratin-8 and -18 antibodies. Clonal isolation of anti-keratin-18-antibody-positive and -negative cell populations demonstrated a correlated enhancement of the invasiveness of these cells and their expression of keratin-18. These results support the notion that the metastatic behavior of lung cancer cells can be characterized with this in vitro system, and that the properties of these progressively invasive cancer cells can be clonally studied.
Am J Respir Cell Mol Biol 1997 Sep
PMID:Selection of invasive and metastatic subpopulations from a human lung adenocarcinoma cell line. 930 22

Precise correlation of histomorphology with the results of molecular genetic analysis is difficult in gastric cancer tissue composed of intestinal and diffuse types. A novel microdissection procedure was applied to correlate p53 and APC allelic loss with histologic type and tumor stage (mucosal vs. invasive cancer) in formalin-fixed, paraffin-embedded specimens of 25 gastric cancers. In addition, mucosal and invasive lesions were dissected from each of 11 invasive gastric cancers to study progression, and allelic loss of the p53 and APC genes was assessed. The p53 gene underwent loss of heterozygosity (LOH) in 4 of 4 informative cases of intestinal-type gastric cancer with mucosal lesions associated with invasion. By contrast, no p53 LOH was found among 6 informative cases with mucosal cancer. LOH of the APC gene in both intestinal and diffuse types of cancer was detected in 4 of 7 and 5 of 6 informative cases, respectively. These data suggest that allelic deletion of the p53 gene in intestinal-type gastric carcinoma predicts the invasive potential of mucosal cancer, and that inactivation of the APC gene plays a role in the genetic tumorigenesis of both intestinal and diffuse types of gastric cancer. Microdissection can correlate genetic alterations with histologic morphology in gastric cancer.
Diagn Mol Pathol 1998 Oct
PMID:Correlation of histologic morphology and tumor stage with molecular genetic analysis using microdissection in gastric carcinomas. 999 Apr 80

The main reason for the recent interest in p53 is that almost 50% of human cancers contain p53 gene mutations. The majority of studies on p53 alterations in breast cancer have been limited to the isolated cases of ductal carcinoma in situ and infiltrating ductal carcinoma. The aims of this study were to determine the status and timing of p53 mutation in the progression from atypical ductal hyperplasia to invasive cancer, and to evaluate the patterns of p53 mutations in noninvasive and invasive lesions. Available lesions of invasive (n=88) and noninvasive (n=76) lesions were microdissected in 107 paraffin-embedded tissues (19 ductal carcinomas in situ, 57 invasive carcinomas with intraductal components, and 31 pure invasive carcinomas) and double-strand DNA sequencing was performed in exon 4-9 of the p53 gene. Among in situ cancers without invasive disease 36.8% had p53 mutations whereas in situ cancer with concurrent invasive disease showed p53 mutations in 33.3% of cases. In particular, two of seven atypical ductal hyperplasias harbored p53 alterations (one insertion and one missense mutation) in exon 8. The invasive component harbored p53 mutations in 30 of 88 cases (34.1%). We also discovered a novel deletion of 14 bp in exon 6 of two invasive lesions. The invasive component (1.33+/-0.13) carried a greater number of p53 mutations than its counterparts (1.19+/-0.10) and demonstrated more frequent multiple mutations (23.3% vs. 15.4%), but without statistical significance. Moreover, no statistical significance could be attached to the mutation frequency in the zinc-binding domains (26.7% vs. 15.4%), the directly DNA contact region (13.3% vs. 15.4%) and the missense mutation of p53 (50.0% vs. 57.7%) of the two groups. Based on our results, in spite of the small number of the lesions investigated, p53 mutation can occur at the stage of atypical ductal hyperplasia. The hypermutability and the specific p53 mutations involving the biologically functional domain (e.g., zinc binding domain or DNA contact region) have an insignificant influence on invasive progression in the breast cancer.
J Mol Med (Berl) 2001 Nov
PMID:The timing and characterization of p53 mutations in progression from atypical ductal hyperplasia to invasive lesions in the breast cancer. 1171 68

We have previously reported on the biallelic expression of the imprinted PEG1/MEST gene in infiltrating carcinomas of the breast. Putative loss of imprinting (LOI) of PEG1/MEST has subsequently also been implicated in the aetiology of lung adenocarcinomas and colon cancer. Taking advantage of our previous study, identifying seven infiltrating carcinomas of the breast, displaying biallelic PEG1/MEST expression, we have analysed the allelic usage of the two alternative PEG1/MEST transcripts encoding isoforms 1 and 2, separately. In addition, expression levels of the two transcripts have been measured by real-time RT-PCR, in order to elucidate the mechanism behind the switch from monoallelic transcription in normal breast tissue to biallelic expression in invasive cancer. The isoform 1 transcript is imprinted in both the paired normal tissue and the breast carcinomas. In contrast, the isoform 2 transcript is biallelically expressed, or in one case expressed from the opposite allele to isoform 1, raising the possibility that isoform 2 is polymorphically imprinted in normal breast tissue. In all the paired normal samples, isoform 1 is predominantly expressed, explaining the monoallelic profiles of these samples. However, in four of the seven biallelic carcinomas, isoform 2 is expressed at higher levels than isoform 1, indicating that a switch in expression from isoform 1 to isoform 2 is responsible for the biallelic profiles in these samples. Our results not only suggest a novel mechanism leading to biallelic expression detected when analysing the common 3'-UTR of the PEG1/MEST transcriptional unit, they are also indicative of the existence of further alternative PEG1/MEST transcripts.
Hum Mol Genet 2002 Jun 01
PMID:Promoter switch: a novel mechanism causing biallelic PEG1/MEST expression in invasive breast cancer. 1202 87

Matrilysin (matrix metalloproteinase-7) plays a part in the initiation and growth of colorectal tumors; expression of this protein has been implicated in tumor invasion and metastasis. To date, matrilysin expression in ulcerative colitis (UC)-associated tumorigenesis has not been studied. The aim of this study was to assess the immunohistochemical expression of matrilysin at different stages of UC-associated neoplasia. Paraffin-embedded specimens from 25 patients with UC without dysplasia, UC-related low-grade dysplasia (LGD) and high-grade dysplasia (HGD), and UC-associated carcinoma as well as four colon biopsy samples with no abnormality were examined using an anti-human matrilysin monoclonal antibody and standard immunoperoxidase techniques. Matrilysin expression was recorded as the number of positive cases and the percentage of positive crypts as follows: normal: none of four; negative results for dysplasia: seven of 12 (< 10%); LGD: nine of 15 (< 10%); HGD: nine of 13 (11-50%); and invasive carcinoma: six of seven (> 50%). The results indicated an apparent switch from focal expression of matrilysin in UC-related low-grade dysplasia to widespread expression in high-grade dysplasia and invasive cancer, mimicking the pattern of expression in sporadic colorectal cancer. Although the sample size is small and further investigation therefore is required, the results suggest the possible role of anti-matrix metalloproteinase therapy in reducing the risk of progression from LGD to cancer in patients with ulcerative colitis. Published 2002 Wiley-Liss, Inc.
Mol Carcinog 2002 Jun
PMID:Matrilysin (matrix metalloproteinase-7) expression in ulcerative colitis-related tumorigenesis. 1211 11

The prevention of cancer is one of the most important public health and medical practices of the 21st century. We have made much progress in this new emerging field, but so much remains to be accomplished before widespread use and practice become common place. Cancer chemoprevention encompasses the concepts of inhibition, reversal, and retardation of the cancer process. This process, called carcinogenesis, requires 20-40 years to reach the endpoint called invasive cancer. It typically follows multiple, diverse and complex pathways in a stochastic process of clonal evolution. These pathways appear amenable to inhibition, reversal or retardation at various points. We must therefore identify key pathways in the evolution of the cancer cell that can be exploited to prevent this carcinogenesis process. Basic research is identifying many genetic lesions and epigenetic processes associated with the progression of precancer to invasive disease. Many of these early precancerous lesions favor cell division over quiescence and protect cells against apoptosis when signals are present. Many oncogenes are active during early development and are reactivated in adulthood by aberrant gene promoting errors. Normal regulatory genes are mutated, making them insensitive to normal regulatory signals. Tumor suppressor genes are deleted or mutated rendering them inactive. Thus there is a wide range of defects in cellular machinery which can lead to evolution of the cancer phenotype. Mistakes may not have to appear in a certain order for cells to progress along the cancer pathway. To conquer this diverse disease, we must attack multiple key pathways at once for a predetermined period of time. Thus, agent combination prevention strategies are essential to decrease cancer morbidity. Furthermore, each cancer type may require custom combination of prevention strategies to be successful.
J Biochem Mol Biol 2003 Jan 31
PMID:Current mechanistic approaches to the chemoprevention of cancer. 1254 78

The aim of this study was to investigate whether there is a correlation between (99m)Tc-sestamibi uptake and histological malignancy grade in breast carcinoma. Such a correlation could, prior to surgery and histopathological analysis, facilitate selection of patients who need adjuvant therapy. Ninety-six patients with mammographically determined lesions and/or a palpable tumour suspected for malignancy underwent (99m)Tc-sestamibi scintimammography prior to surgery. The final diagnosis was determined by histopathological examination. Benign lesions, cancer in situ and tumours located medially in the breast were excluded. Fifty-three invasive cancer lesions in 53 patients were finally included in the study. Planar scintigraphic breast imaging included two prone lateral projections and one anterior supine projection taken 10 min after injection of 700 MBq (99m)Tc-sestamibi. Focal (99m)Tc-sestamibi uptake in breast lesions was used as the scintigraphic criterion of abnormality. Tumour to background ratios were calculated with partial volume compensation, and histological malignancy grading was performed according to the Elston classification. A correlation was found between (99m)Tc-sestamibi uptake and histological malignancy grade in invasive breast carcinomas ( P<or=0.037).
Eur J Nucl Med Mol Imaging 2003 May
PMID:99mTc-sestamibi uptake and histological malignancy grade in invasive breast carcinoma. 1261 23

Gene expression patterns in ductal carcinoma in situ (DCIS), and in invasive, and metastatic breast tumors were determined using serial analysis of gene expression (SAGE). We used mRNA in situ hybridization to examine gene expression at the cellular level and immunohistochemistry on tissue microarrays to determine association between gene expression patterns and histopathologic characteristics of the tumors. We found that that the most dramatic transcriptome change occurs at the normal to DCIS transition, while there is no clear universal "in situ" or "invasive" tumor molecular signature. From the 16,430 transcripts analyzed, we identified only 5 and 11 that were preferentially up-regulated in DCIS and invasive tumors, respectively. The majority of invasive cancer specific SAGE tags correspond to novel genes. The genes we identified may define biologically and clinically meaningful subgroups of DCIS with a high risk of progression to invasive disease.
Mol Cancer Res 2003 Mar
PMID:Molecular markers in ductal carcinoma in situ of the breast. 1265 9

Quantitative models from population biology and evolutionary game theory frame the tumor-host interface as a dynamical microenvironment of competing tumor and normal populations. Through this approach, critical parameters that control the outcome of this competition are identified and the conditions necessary for formation of an invasive cancer are defined. Perturbations in these key parameters that destabilize the cancer solution of the state equations and produce tumor regression can be predicted. The mathematical models demonstrate significant theoretical limitations in therapies based solely on cytotoxic drugs. Because these approaches do not alter critical parameters controlling system dynamics, the tumor population growth term will remain positive as long as any individual cells are present so that the tumor will invariably recur unless all proliferative cells are killed. The models demonstrate that such total effectiveness is rendered unlikely by the genotypic heterogeneity of tumor populations (and, therefore, the variability of their response to such drugs) and the ability of tumor cells to adapt to these proliferation constraints by evolving resistant phenotypes. The mathematical models support therapeutic strategies that simultaneously alter several of the key parameters in the state equations. Furthermore, the models demonstrate that administration of cytotoxic therapies will, by reducing the tumor population density, create system dynamics more conducive to perturbations by biological modifiers.
Mol Cancer Ther 2003 Sep
PMID:Application of quantitative models from population biology and evolutionary game theory to tumor therapeutic strategies. 1455 11


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