The change in serum laminin (LN) level and its clinical significance in epithelial ovarian tumor were investigated. The LN levels in serum and ascites samples from 69 patients with epithelial ovarian tumor and 42 cases as control group before and after operation were analyzed by radioimmunoassay. The results showed that the serum LN levels in the patients with malignant tumors (157.85 +/- 14.37 ng/ml) were significantly higher than that in the control group (125.14 +/- 7.03 ng/ml) and in the patients with benign tumors (128.36 +/- 8.75 ng/ml) (both P < 0.01) before operation. The serum LN levels in the malignant group were decreased significantly after operation as compared with those before operation (P < 0.05). The serum LN levels in low-differentiated tumors was higher than those in moderate-differentiated tumors and high-differentiated tumors (P < 0.05). The LN levels in ascites (172.94 +/- 15.26 ng/ml) was significantly higher than in serum (161.34 +/- 6.59 ng/ml) (P < 0.05) in malignant tumors. The serum LN levels in the patients with lymph node metastasis (165.41 +/- 19.91 ng/ml) was obviously higher than those without lymph node metastasis (152.35 +/- 10.34 ng/ml) (P < 0.05). It was concluded that LN levels in serum and acistis were remarkably increased in malignant epithelial ovarian tumors, suggesting that LN might be one of important diameters reflecting tumor biological characteristics.
Ascitic Fluid/*metabolism ; Carcinoma/blood ; Carcinoma/metabolism ; Laminin/*blood ; Laminin/metabolism ; Ovarian Neoplasms/*metabolism ; Tumor Markers, Biological/*blood ; Tumor Markers, Biological/metabolism

Microenvironmental biophysical factors play a fundamental role in controlling cell behaviors including cell morphology, proliferation, adhesion and differentiation, and even determining the cell fate. Cells are able to actively sense the surrounding mechanical microenvironment and change their cellular morphology to adapt to it. Although cell morphological changes have been considered to be the first and most important step in the interaction between cells and their mechanical microenvironment, their regulatory network is not completely clear. In the current study, we generated silicon-based elastomer polydimethylsiloxane (PDMS) substrates with stiff (15:1, PDMS elastomer vs. curing agent) and soft (45:1) stiffnesses, which showed the Young's moduli of ~450 kPa and 46 kPa, respectively, and elucidated a new path in cytoskeleton re-organization in chondrocytes in response to changed substrate stiffnesses by characterizing the axis shift from the secreted extracellular protein laminin β1, focal adhesion complex protein FAK to microfilament bundling. We first showed the cellular cytoskeleton changes in chondrocytes by characterizing the cell spreading area and cellular synapses. We then found the changes of secreted extracellular linkage protein, laminin β1, and focal adhesion complex protein, FAK, in chondrocytes in response to different substrate stiffnesses. These two proteins were shown to be directly interacted by Co-IP and colocalization. We next showed that impact of FAK on the cytoskeleton organization by showing the changes of microfilament bundles and found the potential intermediate regulators. Taking together, this modulation axis of laminin β1-FAK-microfilament could enlarge our understanding about the interdependence among mechanosensing, mechanotransduction, and cytoskeleton re-organization.
Cell Adhesion ; Chondrocytes ; Cytoskeleton/metabolism* ; Elastomers/metabolism* ; Laminin/metabolism* ; Mechanotransduction, Cellular

Cell adhesion is a basic and very important tissue in the field of tissue engineering. Fibronectin and integrins are the most important elements to cell adhesion. Some surface receptors of fibroblast can also conjugate with type I collagen in extracellular matrix (ECM) directly. Laminin receptors on the surface of fibroblast bound to laminin also play a role in cell adhesion. In this paper are reviewed a number of related articles. The structures and function of fibronectin and integrins are discussed in detail; the tendon cell's adhesion structures are also discussed. Yet, there was scarcely any paper on the effects which the preservation of tissue engineered products may have on cells' adhesion fo ECM. Therefore, researching on cell adhesion and finding a way of preservation that has no or very little adverse effect on cell adhesion is an important topic. Results from expected advanced researches on cell adhesion may probably find promising applications in the field of tissue engineering.
Cell Adhesion ; Extracellular Matrix ; metabolism ; Fibroblasts ; cytology ; Fibronectins ; metabolism ; Humans ; Integrins ; metabolism ; Laminin ; metabolism ; Tendons ; metabolism ; Tissue Engineering

The change in serum laminin (LN) level and its clinical significance in epithelial ovarian tumor were investigated. The LN levels in serum and ascites samples from 69 patients with epithelial ovarian tumor and 42 cases as control group before and after operation were analyzed by radioimmunoassay. The results showed that the serum LN levels in the patients with malignant tumors (157.85 +/- 14.37 ng/ml) were significantly higher than that in the control group (125.14 +/- 7.03 ng/ml) and in the patients with benign tumors (128.36 +/- 8.75 ng/ml) (both P < 0.01) before operation. The serum LN levels in the malignant group were decreased significantly after operation as compared with those before operation (P < 0.05). The serum LN levels in low-differentiated tumors was higher than those in moderate-differentiated tumors and high-differentiated tumors (P < 0.05). The LN levels in ascites (172.94 +/- 15.26 ng/ml) was significantly higher than in serum (161.34 +/- 6.59 ng/ml) (P < 0.05) in malignant tumors. The serum LN levels in the patients with lymph node metastasis (165.41 +/- 19.91 ng/ml) was obviously higher than those without lymph node metastasis (152.35 +/- 10.34 ng/ml) (P < 0.05). It was concluded that LN levels in serum and acistis were remarkably increased in malignant epithelial ovarian tumors, suggesting that LN might be one of important diameters reflecting tumor biological characteristics.
Ascitic Fluid ; metabolism ; Biomarkers, Tumor ; blood ; metabolism ; Carcinoma ; blood ; metabolism ; Female ; Humans ; Laminin ; blood ; metabolism ; Male ; Ovarian Neoplasms ; metabolism

OBJECTIVETo observe the expression of laminin and fibronectin in alkali-burned corneas in rats.

METHODSA total of 18 normal Wistar rats were randomly divided into 6 groups (n = 3 in each group). For each rat, one eye was injured by alkali burn, the other one was taken as the normal control. Then all the corneas were surgically removed and the expression of laminin and fibronectin was observed with immunohistochemistry respectively at 7 hours, 1 day, 3 days, 7 days, 14 days and 28 days after alkali burn.

RESULTSCompared with that of the normal controls, the expression of laminin and fibronectin of the burned eyes was dramatically higher at 7 hours, reached peak at 14 days and decreased to the normal level at 28 days after alkali burn.

CONCLUSIONSIn the process of wound healing after alkali burn, the expression of laminin and fibronectin increases dramatically, which suggests that laminin and fibronectin may participate in the process of corneal wound healing.

Animals ; Burns, Chemical ; metabolism ; Corneal Injuries ; Eye Burns ; metabolism ; Fibronectins ; metabolism ; Immunohistochemistry ; Laminin ; metabolism ; Rats ; Rats, Wistar ; Wound Healing ; physiology

OBJECTIVEThe congenital muscular dystrophies (CMD) are a clinically and genetically heterogeneous group of neuromuscular disorders with progressive muscle wasting and weakness that begin during neonatal or early infantile period. To study the clinical diagnosis, immunohistochemical feature and follow-up information of CMD, data of 8 cases with CMD were analyzed.

METHODSImmunohistochemical features of biopsied muscle specimens were summarized and analyzed by using anti-laminin alpha2 (merosin), anti alpha-dystroglycan (alpha-DG) and anti beta-dystroglycan (beta-DG) antibodies.

RESULTSThese patients mostly presented at birth or during the first six months of life with muscle weakness, hypotonia, contractures, and feeding difficulty or respiratory dysfunction. Hematoxylin-eosin staining of skeletal muscle specimens from these patients showed typical characteristics of CMD. Differences in fiber size, with predominantly small and round fibers, and dense connective tissue infiltration were seen. Four of the 8 patients were merosin-stain negative, which might be due to primary merosin deficiency. T2-weighted magnetic resonance imaging of the brain shows abnormalities of the white matter. Four cases were merosin-stain positive, and two of them also had hypoglycosylation of alpha-dystroglycan. Two patients had mental retardation. One of them had optic nerve atrophy and abnormal brain structure.

CONCLUSIONSTwo types of CMD were present in our group. Merosin-deficient congenital muscular dystrophy (congenital muscular dystrophy 1A, MDC1A) was more common, accompanied by abnormalities of the white matter. "Alpha-dystroglycanopathy" could be seen in merosin-positive cases.

Female ; Humans ; Infant ; Laminin ; deficiency ; Male ; Muscular Dystrophies ; congenital ; diagnosis ; metabolism

OBJECTIVETo study the effects of integrin beta1 on the chemotaxis of hepatocellular carcinoma (HCC) cells to laminin (LN).

METHODSA micropipette technique was adopted to investigate the effect of integrin beta1 blockade on pseudopod protrusion of HCC cells in response to LN stimulation. Chemotactic pseudopod protrusion of a HCC cell was evaluated using a dual-pipette set-up, in which two pipettes filled with LN solution were positional in close contact with the same cell, and pseudopod protrusion into each pipette was viewed dynamically and recorded with a tape recorder. The lengths of pseudopods were measured, then plotted against time to obtain a pseudopod growth curve. The integrin beta1 subunit on the surfaces of HCC cells was analyzed by flow cytometry.

RESULTSIn dual pipette chemotaxis experiment, when the two pipettes were filled with LN (50microg/ml, 200microg/ml), pseudopods extended from the HCC cells into each of the pipettes nearly symmetrically. Upon addition of anti-CD29 (20microg/ml) to one of the pipettes, the pseudopod protrusion was blocked almost completely, while the pseudopod protrusion into the opposite pipette became more evidently, with larger maximum length. The expression rate of integrin beta1 on the cells was up to 95.78%.

CONCLUSIONIntegrin beta1 subunit is the important receptor for mediating HCC cells chemotaxis to laminin.

Carcinoma, Hepatocellular ; pathology ; Cell Adhesion ; Cell Line, Tumor ; Chemotaxis ; Humans ; Integrin beta1 ; immunology ; metabolism ; physiology ; Laminin ; metabolism ; Liver Neoplasms ; pathology

To carry out the secretive expression of human 67 kD laminin receptor (67LR), recombinant expression plasmid pPIC9K-67LR was constructed by inserting of 67LR cDNA into yeast expression vector pPIC9K. The 67LR protein was expressed in Pichia pastoris after induced by methanol, and about 12.56 mg electrophoresis purity 67LR could be obtained after the purification of 1L culture using affinity chromatograph column. In vitro competitive binding assay showed that target protein has an excellent biological activity. The successful expression of 67LR has placed a solid foundation for the research on structure and functions of 67LR.
Genetic Vectors ; Humans ; Pichia ; genetics ; metabolism ; Plasmids ; genetics ; Receptors, Laminin ; biosynthesis ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; metabolism

OBJECTIVETo study the expression and significance of structural proteins, VEGF and Ang-1 in cavernous venous malformations of the body surface.

METHODSTissue samples came from 25 cases of cavernous venous malformations, 12 cases of normal moderate veins and 12 cases of normal small veins. Envision immunohistochemical stain was used to investigate the expression of IV collagen, fibronectin, laminin, VEGF and Ang-1. The results were analyzed semi-quantitatively.

RESULTSThe distribution of structural proteins in cavernous venous malformations is similar to moderate and small veins, but the expression in venous malformations is less obviously. VEGF expression in cavernous venous malformations and small veins is stronger obviously than moderate veins. Ang-1 expression in small veins is stronger remarkably than cavernous venous malformations and moderate veins.

CONCLUSIONThe abnormal expression of structural proteins may be an important factor in etiopathology and progress of cavernous venous malformations. There is disturbance of blood vessel remodelling in the sinusoid of cavernous venous malformations, with which the less expression of Ang-1 may be related.

Angiopoietin-1 ; metabolism ; Collagen Type IV ; metabolism ; Fibronectins ; analysis ; Hemangioma, Cavernous ; metabolism ; Humans ; Laminin ; metabolism ; Vascular Endothelial Growth Factor A ; metabolism ; Veins ; abnormalities ; metabolism

OBJECTIVETo explore the relationship between the extracellular matrix and apoptosis of intestinal epithelium after burn injury.

METHODSThirty Wistar rats were employed in the study and were randomly divided into normal control (C) and 6 PBH (postburn hour), 12 PBH, 1 PBD (postburn day), 3 PBD and 5 PBD group with 5 rats in each group. The rats in burn groups were sacrificed at 0, 6 and 12 PBHs and 1, 3 and 5 PBDs. The apoptotic cell count and the caspases-3 activity of intestinal mucosal epithelium, and the extracellular matrix component laminin and type IV collagen were determined and their correlation was analyzed.

RESULTSThe apoptotic cell count and the caspases-3 activity of intestinal mucosal epithelium in burn groups were obviously higher than those in C group (P < 0.05 or 0.01), while the intestinal mucosal contents of laminin and type IV collagen in burned groups were much lower than those in C group (P < 0.05 or 0.01). By linear correlative analysis, it was shown that the changes in the intestinal mucosal contents of laminin and type IV collagen in burned groups were negatively correlated with the change in apoptotic cell count (r = -0.575, -0.613, P < 0.05).

CONCLUSIONIntestinal epithelial apoptosis was enhanced after burn injury, and it was correlated with the change in the components of the extracellular matrix.

Animals ; Apoptosis ; Burns ; metabolism ; pathology ; Caspase 3 ; metabolism ; Collagen Type IV ; metabolism ; Extracellular Matrix ; metabolism ; Female ; Intestinal Mucosa ; metabolism ; pathology ; Laminin ; metabolism ; Male ; Rats ; Rats, Wistar