PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “correlation matrix”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 703 records · Page 39Linked to original sources
PubMed1999

Correlation between expression of matrix metalloproteinase-2 (MMP-2), and matrix metalloproteinase-9 (MMP-9) and angiogenesis in colorectal adenocarcinoma.

Matrix metalloproteinases-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), which degrade extracellular matrix, are believed to play a crucial role in tumor invasion and metastasis. Angiogenesis is also perceived as an important step in tumor growth and metastasis. To investigate the expression of MMPs and the correlation between the expression of MMPs and angiogenesis in colorectal adenocarcinoma, we studied 72 cases of colorectal adenocarcinoma in Inha University Hospital from 1996 to 1997. We evaluated the expression of MMPs by immunohistochemistry and angiogenesis by counting the microvessels. The expression of MMP-2 was increased according to the Astler-Coller stage (p< 0.05). Angiogenesis in the metastatic group was higher than that of the localized one (p<0.05). The expression of MMP-2 positively correlated with angiogenesis (p<0.05), and marked expression of MMP-9 positively correlated with angiogenesis (p<0.05). The present results suggest that the expression of MMP-2 provides clues for tumor progression and angiogenesis provides significant information to predict whether metastasis is present in colorectal adenocarcinoma.

Adenocarcinoma↗
PubMed2006

Spatiotemporal expression control correlates with intragenic scaffold matrix attachment regions (S/MARs) in Arabidopsis thaliana.

Scaffold/matrix attachment regions (S/MARs) are essential for structural organization of the chromatin within the nucleus and serve as anchors of chromatin loop domains. A significant fraction of genes in Arabidopsis thaliana contains intragenic S/MAR elements and a significant correlation of S/MAR presence and overall expression strength has been demonstrated. In this study, we undertook a genome scale analysis of expression level and spatiotemporal expression differences in correlation with the presence or absence of genic S/MAR elements. We demonstrate that genes containing intragenic S/MARs are prone to pronounced spatiotemporal expression regulation. This characteristic is found to be even more pronounced for transcription factor genes. Our observations illustrate the importance of S/MARs in transcriptional regulation and the role of chromatin structural characteristics for gene regulation. Our findings open new perspectives for the understanding of tissue- and organ-specific regulation of gene expression.

Arabidopsis↗
PubMed1998

Differential nuclear matrix protein expression in prostate cancers: correlation with pathologic stage.

PURPOSE: Nuclear Matrix Proteins (NMP) have been shown to be tissue and cell-type specific. Several unique NMPs have been investigated in various cancerous tissues, including prostate, bladder and kidney, and some are presently utilized as tumor markers. This study was aimed at characterizing the differential NMP expression in the pathologically more aggressive prostate cancers. METHODS: High resolution two-dimensional gel electrophoresis and silver staining was used to elucidate the NMP distribution of fresh prostate cancer nuclei, obtained from 39 radical prostatectomy specimens, surgically removed from men with clinically localized prostate cancer. Based on the final pathological grading, specimens were grouped according to predicted prognosis: poor--with seminal vesicle (SV) or lymph node (LN) involvement or established capsular penetration (ECP) with gleason score >7; intermediate--organ confined (OC) or focal capsular penetration (FCP) with gleason score 7 or ECP with gleason score 6; and good--with OC or FCP and gleason score <7. RESULTS: A specific charged protein (YL-1) of molecular weight 76 kD and isoelectric range 6.0-6.6 was found to be consistently present in 19 of 19 aggressive cancers. It was present only in 1 of 10 in the group with good prognosis and weakly positive in 9 of 10 in the intermediate group. CONCLUSIONS: Within this preliminary study, the expression of YL-1 appears to be related to aggressive prostate cancer, suggesting a potential marker of poor prognosis for clinically localized prostate cancer. Further characterization of the identity and function of this NMP is needed to fully ascertain its clinical potential.

Antigens, Nuclear↗
PubMed2002

Correlation of cartilage oligomeric matrix protein (COMP) levels in equine tendon with mechanical properties: a proposed role for COMP in determining function-specific mechanical characteristics of locomotor tendons.

Over-strain injury of the superficial digital flexor tendon (SDFT) is a common injury in the horse. Tendon appears to adapt to loads placed on it during development, but fatigue damage accumulates after skeletal maturity, which is inadequately repaired and predisposes to clinical tendinitis. In any population of horses, there is a wide variation in SDFT mechanical properties. A noncollagenous protein, cartilage oligomeric matrix protein (COMP), is particularly abundant during growth in the equine SDFT and has been proposed to have an organisational role in the formation of collagenous matrices. This study aimed to determine whether COMP levels were correlated to mechanical properties at skeletal maturity. Tendons from 2 groups of 12 horses were analysed: Group 1 horses with restricted age, 2 years +/- 2 months, showed a significant correlation between both ultimate tensile stress modulus of elasticity and stiffness and COMP, while Group 2 mature horses with varying age did not, because of age- and exercise-induced loss of COMP. These data supports the hypothesis that COMP is an important mediator in the growth of tendon. This data would suggest that the identification of low COMP levels in tendon during growth would indicate horses prone to tendon injury and methods of promoting COMP synthesis during growth would potentially improve tendon quality and reduce the risk of subsequent tendinitis.

Age Factors↗
PubMed2000

A new in vitro/in vivo kinetic correlation method for nitrofurantoin matrix tablet formulations.

The kinetic distributions of in vitro percentage release and in vivo percentage urinary excretion rates of nitrofurantoin from matrix tablets were plotted using a kinetic program. In vitro release rates were determined using the USP paddle and half-change methods. Urinary excretion curves of the drug were characterized by means of the statistical moments. The individual linear correlations between each in vitro and in vivo kinetic distribution were established, and regression equations were calculated. The application results of the best correlations obtained were evaluated according to in vivo results. A reversed kinetic procedure was applied for transformation of the correlated kinetic values to the drug percentage release rates. The modified Langenbucher kinetic showed excellent linear correlation (r = .9985). The method that is proposed in this study, the kinetic correlation program, is simple, independent of time, and suggests that it is possible to use kinetic distributions in the in vitro/in vivo correlation. This study also suggests using kinetic correlation to investigate the suitability of the in vitro dissolution methods with the in vivo drug dissolution.

Anti-Infective Agents, Urinary↗
PubMed2002

Correlation of a novel matrix protein with the degree of cartilage degradation.

Cartilage-derived retinoic acid-sensitive protein (CD-RAP), also referred to as melanoma-inhibiting activity (MIA), is detected physiologically only in cartilage tissue and pathologically in malignant melanoma. Recent studies indicated that this protein might be useful as a marker for altered joint metabolism or damage. The purpose of this study was to evaluate whether there is any correlation between the degree of cartilage degradation and levels of this protein. In a prospective cross-sectional study, synovial fluid samples were obtained from 67 consecutive patients undergoing surgery of the knee joint. The degree of cartilage degradation was determined intraoperatively using the Outerbridge and Noyes classifications. MIA/CD-RAP was measured by a commercially available enzyme-linked immunosorbent assay (ELISA). The marker levels were compared against the Outerbridge and Noyes classifications and the correlation coefficients were calculated. At advanced stages of cartilage degradation, there were decreased synovial fluid levels of MIA/CD-RAP. The correlation coefficients were -0.449 and -0.418 for the Outerbridge and Noyes classifications, respectively, with large 95% confidence intervals. While the physiological function of MIA/CD-RAP is still unclear, the results indicate that MIA/CD-RAP levels depend on the degree of cartilage degradation. Despite the high interindividual variations, MIA/CD-RAP might be useful as a marker to monitor degenerative joint lesions.

Adolescent↗
PubMed1998

Phagocytosis of cross-linked gelatin matrix by human breast carcinoma cells correlates with their invasive capacity.

During invasion and metastasis, cancer cells interact closely with the extracellular matrix molecules by attachment, degradation, and migration. We demonstrated previously the local degradation of fluorescently labeled gelatin matrix by cancer cells at invasive membrane protrusions, called invadopodia. Using the newly developed quantitative fluorescence-activated cell sorting-phagocytosis assay and image analysis of localized degradation of fluorescently labeled matrix, we document here that degradation and site-specific removal of cross-linked gelatin matrix is correlated with the extent of phagocytosis in human breast cancer cells. A higher phagocytic capacity is generally associated with increasing invasiveness, documented in other invasion and motility assays as well. Gelatin phagocytosis is time and cell density dependent, and it is mediated by the actin cytoskeleton. Most of the intracellular gelatin is routed to actively acidified vesicles, as demonstrated by the fluorescent colocalization of gelatin with acidic vesicles, indicating the intracellular degradation of the phagocytosed matrix in lysosomes. We show here that normal intracellular routing is blocked after treatment with acidification inhibitors. In addition, the need for partial proteolytic degradation of the matrix prior to phagocytosis is demonstrated by the inhibition of gelatin phagocytosis with different serine and metalloproteinase inhibitors and its stimulation by conditioned medium containing the matrix metalloproteinases MMP-2 and MMP-9. Our results demonstrate that phagocytosis of extracellular matrix is an inherent feature of breast tumor cells that correlates with and may even directly contribute to their invasive capacity. This assay is useful for screening and evaluating potential anti-invasive agents because it is fast, reproducible, and versatile.

Animals↗
PubMed2005

[Correlation between expression of matrix metalloproteinase-2 and angiogenesis in esophageal carcinoma].

OBJECTIVE: To study expression of MMP-2 in relation to microvessel density (MVD) in esophageal carcinoma. METHODS: Forty-eight specimens of esophageal carcinoma (Ec) and 17 specimens of grade II + III epithelial dysplasia (Dy) close to the tumor and 12 specimens of normal tissue (Nt) along the incisional margin were examined by S-P immunohistochemical staining with anti-MMP-2 monoclonal antibody. An anti-CD34 monoclonal antibody was used to show MVD. RESULTS: MMP-2 expression in Ec was remarkably higher than that in Dy, which was higher than that in Nt. MMP-2 expression in Ec and Dy was significantly correlated with MVD in the tumor and nearby tissue. MMP-2 expression and MVD in Ec significantly associated with lymph node metastasis. CONCLUSION: Expression of MMP-2 plays an important role in angiogenesis and lymph node metastasis of esophageal cancer.

Carcinoma, Squamous Cell↗
PubMed2006

Cyclooxygenase-2 expression correlates with membrane-type-1 matrix metalloproteinase expression in colorectal cancer tissue.

PURPOSE: Elevated expression of cyclooxygenase-2 has been found in colorectal cancer. One of the mechanisms through which cyclooxygenase-2 affects tumorigenesis is through its overexpression, which leads to increased invasiveness of cancer cells. A crucial step in this pathway is thought to be the induction of membrane-type-1 matrix metalloproteinase, which activates matrix metalloproteinase-2. However, to date there have been few clinicopathologic studies concerning cyclooxygenase-2-mediated invasiveness in human colorectal cancer tissues. METHODS: We performed immunohistochemical analysis of the respective antigens on colorectal cancer specimens obtained by surgical resections from 96 patients with colorectal cancer. RESULTS: Cyclooxygenase-2 and membrane-type-1 matrix metalloproteinase expression was positive exclusively in cancer cells in 88 cases (92 percent) and 23 cases (24 percent), respectively. All 23 cases expressing membrane-type-1 matrix metalloproteinase also expressed cyclooxygenase-2. Matrix metalloproteinase-2 expression was positive in cancer cells in 20 cases (21 percent) and stromal cells in 52 cases (54 percent). Expression of matrix metalloproteinase-2 in cancer cells correlated with lymphatic invasion and local recurrence. Statistically, a significant correlation was found between cyclooxygenase-2 and membrane-type-1 matrix metalloproteinase expression, and membrane-type-1 matrix metalloproteinase and matrix metalloproteinase-2 expression in cancer cells. There was no association between cyclooxygenase-2 expression and matrix metalloproteinase-2 expression. However, immunostaining of serial sections revealed that in the majority of cases examined, nearly 100 percent of cancer cells expressing matrix metalloproteinase-2 also coexpressed cyclooxygenase-2. CONCLUSIONS: This study indicates strong association between both cyclooxygenase-2 and membrane-type-1 matrix metalloproteinase expression, and membrane-type-1 matrix metalloproteinase and matrix metalloproteinase-2 in colorectal cancer. These results support our thesis of a direct correlation between cyclooxygenase-2 and membrane-type-1 matrix metalloproteinase expression--with consequent association between cyclooxygenase-2 and matrix metalloproteinase-2 activation, and tumor invasiveness andrecurrence in certain cases of colorectal cancer.

Adult↗
PubMed1997

Positive correlation between inhibitors of matrix metalloproteinase 1 and matrix metalloproteinases in malignant ovarian tumor tissues.

To investigate the relation between matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) in malignant ovarian tumor, MMP and TIMP activities in conditioned media of 16 malignant ovarian tumor tissues and six normal ovaries were detected by zymography and reverse zymography, respectively and were quantitated with a densitometer. TIMP-1 and TIMP-2 were detected in all normal and malignant ovarian tumor tissues by reverse zymography. In normal ovaries, the intensity of TIMP-2 bands was stronger than TIMP-1, but in malignant tumor tissues those of TIMP-1 were stronger. The ratios of TIMP-1 to TIMP-2 and MMP-9 to MMP-2 were significantly higher in malignant tumor tissues than in normal ovaries (P < 0.001). TIMP activity consisting of TIMP-1 and TIMP-2 correlated significantly to MMP activity of MMP-2 and MMP-9 (r = 0.67, P < 0.005). There was a significant correlation between TIMP-1 activity and MMP activity (r = 0.72, P < 0.001), but no correlation was observed between TIMP-2 activity and MMP activity. The high level of TIMP-1 appeared to be related to malignant phenotype in ovaries as well as the high level of MMP-9.

Adolescent↗
PubMed2006

[The correlation between polymorphisms of matrix metalloproteinase-2 and -9 genes and colorectal cancer of Chinese patients].

OBJECTIVE: To investigate whether the polymorphisms of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) promoters contribute to the development and progression of colorectal cancer in Chinese population. METHODS: the PCR-based denaturing high-performance liquid chromatography or PCR-restriction fragment length polymorphism technique respectively was applied to analyze the MMP-2 -1306C/T and MMP-9 -1562C/T polymorphisms in normal group (126 individuals) and colorectal cancer group (126 cases). Genotype frequencies were compared between patients and matched controls, and the association of genotypes with clinical-pathological parameters was studied. RESULTS: The frequency of the CC genotype in the MMP-2 gene polymorphism was significantly increased in colorectal cancer patients when compared with controls (P<0.05), and individuals with the CC genotype had an increased risk of developing colorectal cancer compared to those with CT+TT genotypes (OR: 1.959; 95%CI: 1.055-3.637). Significant correlation was found between the depth of tumor invasion and MMP-2 -1306C/T polymorphism in colorectal cancer patients. However, the genotype frequencies of MMP-9 -1562C/T in colorectal cancer patients were similar to those in control subjects. CONCLUSION: Our results indicate that MMP-2 -1306 C/T polymorphism may be associated with genetic susceptibility to colorectal cancer and the invasive capability of colorectal cancer in Chinese patients. And it is easier for the CC genotype cancer to invade through bowel wall.

Adult↗
PubMed1994

Increased gelatinolytic activity in keratoconus keratocyte cultures. A correlation to an altered matrix metalloproteinase-2/tissue inhibitor of metalloproteinase ratio.

Keratoconus is a noninflammatory corneal disorder characterized by gradual stromal thinning and astigmatism. Altered degradation of corneal extracellular matrix is a suggested etiology for this disorder. In the present study we established keratocyte cultures from normal and keratoconus corneas and investigated the roles that matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMP, TIMP-2) may play. After chemical modification (reduction and alkylation) to remove the inhibitor and activation of enzyme with p-aminophenylmercuric acetate (APMA), keratoconus-conditioned media displayed a significant increase (p < 0.05) in the total potential gelatinolytic activity when compared with normal culture media treated in a similar manner. Basal levels of gelatinolytic activity in keratoconus culture media (no reduction, alkylation, or APMA treatment), determined by two different assay methods, tended to be about twice that of normal cell cultures. By zymography, both keratoconus and normal cultures showed identical enzyme patterns, which represented MMP-2 (72 kDa) in its proform and, depending on the treatment of the media, varying amounts of activated MMP-2 (65 kDa). This suggests that the increased gelatinolytic activity in keratoconus was not correlated with an increased appearance of either the 65-kDa-activated form of MMP-2 or a new MMP species. In addition, no differences in the amount of MMP-2 were detected that could account for the increased activities in keratoconus cultures. However, a relative decline in the detectable TIMP levels in keratoconus cultures resulted in an apparent three-fold increase in the ratio of MMP-2/TIMP. Northern blots showed no significant changes in mRNA levels for MMP-1, MMP-2, MMP-3, TIMP, or TIMP-2. These data suggest that a possible alteration in the interaction between MMP-2 and TIMP may play a role in the increased gelatinolytic activity seen in keratoconus tissues.

Adolescent↗
PubMed1996

Differential expression of membrane-type matrix metalloproteinase and its correlation with gelatinase A activation in human malignant brain tumors in vivo and in vitro.

In this study, we investigated the expression of activated gelatinase A and membrane-type metalloproteinase (MT-MMP) induced by concanavalin A (ConA) in four highly invasive glioma cell lines (UWR2, UWR3, U251MG, and SNB-19). We also examined gelatinase A and MT-MMP expression in human brain tumor tissues in vivo. Gelatin zymography showed that all four cell lines expressed latent progelatinase A (M(r) 66,000). Activated gelatinase A (M(r) 62,000) was induced by ConA in only UWR2 or UWR3 cells. MT-MMP mRNA was present in all four cell lines prior to ConA treatment, and the relative hybridization signals were 1, 0.80, 0.25, and 0.15 in UWR2, UWR3, U251MG, and SNB-19 cells, respectively. These mRNA signals were dramatically increased (2,8-, 5.4-, and 2.2-fold in UWR2, UWR3, and U251MG cells, respectively) following ConA treatment; however, MT-MMP mRNA expression was unchanged in SNB-19 cells. MT-MMP protein was detected in various amounts in the four cell lines, but only after ConA pretreatment. The amount of MT-MMP mRNA was unchanged in SNB-19 after ConA treatment, and the MT-MMP mRNA level in ConA-treated U251MG was lower than in UWR2 and UWR3 without ConA treatment. MT-MMP protein was detected in SNB-19 and U251 cell lines only after ConA treatment. Gelatin zymography of human brain tumor tissues revealed that almost all samples examined contained a latent form of gelatinase A, whereas the activated form of gelatinase A was only seen in metastatic lung adenocarcinomas and malignant astrocytomas, and especially in glioblastomas. MT-MMP mRNA levels were significantly higher in malignant astrocytomas than in low-grade gliomas and normal brain tissues. These results were confirmed by PCR analysis, which showed that MT-MMP mRNA was absent or barely detectable in normal brain white matter but was easily detectable in malignant astrocytomas. Immunohistochemistry of MT-MMP in frozen sections showed that MT-MMP was localized in neoplastic astrocytes of malignant astrocytomas but was undetectable in normal white brain matter. The data indicate that MT-MMP is present in malignant human glial tumors and that MT-MMP expression correlates with expression and activation of gelatinase A during malignant progression in vivo. A direct correlation between the levels of MT-MMP protein and its transcripts was not found in vitro, suggesting that MT-MMP expression in glioma cell lines might be regulated either at the level of transcription message stability or at posttranscription. Altered MT-MMP expression might contribute, in part, to gelatinase A activation, which in turn facilitates invasion of these tumors.

Astrocytoma↗
PubMed2002

Circulation level of matrix metalloproteinase-9 is correlated with disease severity in tuberculosis patients.

SETTING: Parenchymal lung destruction accompanied by active tuberculosis is, at least in part, caused by host as well as bacillus metalloproteinases. Mycobacterium tuberculosis has been shown to stimulate MMP-9 expression in the lung of infected organisms. DESIGN: We have used quantitative zymography and computer-assisted image analysis to measure the levels of type IV collagenases in 20 serum samples of patients with active tuberculosis and in 23 serum samples of healthy volunteers. RESULTS: Mean levels of the serum MMP-9 were over three-fold higher in tuberculous samples compared with normal serum (P < 0.0001), whereas the MMP-2 levels did not differ in these two groups. The levels of MMP-9 were significantly higher in subjects with advanced disease than in those with only limited disease changes (P < 0.05). CONCLUSIONS: We suppose that the elevation of serum MMP-9 levels in patients with tuberculosis is affected by the augmentation of synthesis and/or secretion of this enzyme by inflammatory cells in response to M. tuberculosis infection. The observed association between the serum MMP-9 level and the extent of radiological change suggests that the quantification of the serum level of this enzyme may constitute a supplementary test in pulmonary tuberculosis diagnostics.

Case-Control Studies↗
PubMed2004

Matrix metalloproteinase-2 and matrix metalloproteinase-9 expressions correlate with the recurrence of intracranial meningiomas.

BACKGROUND: We studied whether or not the expressions of MMP-2 and MMP-9 were correlated with the proliferative potential or recurrence of intracranial meningiomas. METHODS: The expressions of MMP-2 and MMP-9 of 56 meningioma tissues were examined and scored by immunohistochemistry (IHC). Expressions of the mRNA of each MMP were also examined by reverse transcriptase polymerase chain reaction (RT-PCR) assay in 15 cases. The relationships between IHC score and each of age, sex, tumor location, histology, MIB-1 labeling index (LI), and recurrence or regrowth rate were studied. RESULTS: Nine of 56 cases showed recurrence or regrowth. IHC revealed that MMP-2 was highly expressed in 13 of 56 cases, whereas MMP-9 was highly expressed in 22 of 56 cases. Among the 15 cases analyzed by RT-PCR assay, MMP-2 and MMP-9 were expressed in 9 and 13 cases, respectively. Based on the Kaplan-Meier curve, the high expressions of MMPs were related to recurrence/regrowth (MMP-2: p < 0.001; MMP-9: p < 0.05). No significant relationship was observed between the expressions of MMPs and either age, sex, tumor location, or MIB-1 LI. CONCLUSIONS: Our study indicated that MMP-2 and MMP-9 expressions are prognostic factors predicting the recurrence of meningioma, independent of proliferative potential.

Aged↗
PubMed1998

Experimental pneumococcal meningitis in rabbits: the increase of matrix metalloproteinase-9 in cerebrospinal fluid correlates with leucocyte invasion.

Gelatinolytic activity of matrix metalloproteinases (MMPs), particularly MMP-9 and MMP-2, was studied by quantitative zymography in a rabbit model of bacterial meningitis during 24 h after inoculation with Streptococcus pneumoniae. In cerebrospinal fluid (CSF), MMP-2 was constitutively present and its level did not change during the experiment. In contrast, MMP-9, hardly detectable in CSF of healthy animals, increased dramatically. The increase of MMP-9 was correlated with both, an increase of CSF cell count and of total protein concentration. Intrathecal production of MMP-9 and MMP-2 was demonstrated by zymography of equal amounts of total protein from CSF and serum. Homogenates, prepared from various cortical regions of infected rabbits did not show increase of MMP activities. On the other hand, leucocytes isolated from CSF expressed high levels of MMP-9 suggesting a significant contribution of these cells to the elevation of MMP-9 activity in this body fluid.

Animals↗
PubMed1995

Metastasis of C1300 and TBJ murine neuroblastomas correlates with expression of matrix metalloproteinases.

Because metalloproteinases, specifically type IV collagenases, may mediate metastasis, 72- and 92-kDa collagenase activities were evaluated in two murine neuroblastoma cell lines: non-metastatic C1300 and metastatic TBJ. Zymogram analysis demonstrated that 72- and 92-kDa collagenases were associated only with metastatic TBJ. Three human neuroblastoma cell lines were then evaluated by zymogram and Western blot analyses: 72-kDa collagenase was found in metastatic SK-N-SH and IMR-32, but not in SK-N-MC, which may be a peripheral neuroectodermal tumor and not a neuroblastoma. Therefore, 72- and 92-kDa collagenases may be markers of metastasis in neuroblastoma and may aid in differentiation from other small blue cell tumors.

Animals↗