Actins ; immunology ; metabolism ; Antibodies, Monoclonal ; analysis ; Antigens, CD34 ; immunology ; metabolism ; Breast Neoplasms ; metabolism ; Female ; Humans ; Immunohistochemistry ; methods ; Lung Neoplasms ; metabolism ; Membrane Proteins ; immunology ; metabolism ; Tumor Suppressor Protein p53 ; immunology ; metabolism

OBJECTIVETo investigate the role of excretory/secretory antigens from Clonorchis sinensis (CsESAs) in hepatic fibrosis induced by C. sinensis infection in rats and explore the possible mechanism.

METHODSCsESAs was collected from adult C. sinensis cultured in sterile condition for 12 h and injected intraperitoneally in Wistar rats. Masson staining was used to observe the changes in the hepatic collagen fiber after the injection. HE staining and immunofluorescence staining were performed to detect the expression of alpha-smooth muscle actin (alpha-SMA) to examine the proliferation and the activity of hepatic stellate cells. The specific antibody titer of CsESAs was determined using enzyme-linked immunosorbent assay to investigate the role of the antigen-antibody complex in the development of hepatic fibrosis.

RESULTSAfter intraperitoneal injection of CsESAs, obvious hepatic fibrosis and hepatic stellate cell proliferation and activation were observed in the rat livers. The severity of the hepatic fibrosis was associated with the dose of CsESAs injected, whereas the titer of the specific antibody against CsESAs showed no direct relation to the hepatic fibrosis.

CONCLUSIONIntraperitoneal injection of CsESAs can cause hepatic stellate cell activation and hepatic fibrosis in rats, but the antigen-antibody complex does not seem to play the key role in the activation of the hepatic stellate cells.

Actins ; metabolism ; Animals ; Antigens, Helminth ; immunology ; Clonorchiasis ; parasitology ; Clonorchis sinensis ; immunology ; pathogenicity ; Hepatic Stellate Cells ; pathology ; Liver Cirrhosis ; immunology ; parasitology ; Male ; Rats ; Rats, Wistar

p21-activated kinase (PAK)-interacting exchange factor (PIX) is known to be involved in regulation of Cdc42/Rac GTPases and PAK activity. PIX binds to the proline-rich region of PAK, and regulates biological events through activation of Cdc42/Rac GTPase. To further investigate the role of PIX we produced monoclonal antibodies (Mab) against beta PAK. Three clones; N-C6 against N-terminal half and C-A3 and C-B7 against C- terminal half of beta PAK were generated and characterized. N-C6 Mab detected beta PAK as a major band in most cell lines. C-A3 Mab recognizes GIT-binding domain (GBD), but it does not interfere with GIT binding to beta PAK. Using C-A3 Mab possible beta PAK interaction with actin in PC12 cells was examined. beta PAK Mab (C-A3) specifically precipitated actin of the PC12 cell lysates whereas actin Mab failed to immunoprecpitate beta PAK. Co-sedimentation of PC12 cell lysates with the polymerized F-actin resulted in the recovery of most of beta PAK in the cell lysates. These results suggest that beta PAK may not interact with soluble actin but with polymerized F-actin and revealed that beta PAK constitutes a functional complex with actin. These data indicate real usefulness of the beta PAK Mab in the study of beta PAK role(s) in regulation of actin cyoskeleton.
Actins/*metabolism ; Animals ; Antibodies, Monoclonal/immunology ; Cell Cycle Proteins/immunology/metabolism/*physiology ; Cell Line, Tumor ; Cytoskeletal Proteins/metabolism ; Epitope Mapping ; Guanine Nucleotide Exchange Factors/immunology/metabolism/*physiology ; Immunoprecipitation ; Mice ; Microfilaments/*physiology ; Protein Structure, Tertiary ; Rats ; Research Support, Non-U.S. Gov't

BACKGROUNDInsulin-like growth factor binding protein-related protein 1 (IGFBPrP1) can activate hepatic stellate cells and increase extracellular matrix (ECM) in vitro. However, the effects of IGFBPrP1 in mice with hepatic fibrosis, and the mechanisms of these effects, are currently unknown. We aim to address these issues in this study.

METHODSIntraperitoneal injection of thioacetamide (TAA) is a classic method for establishing a mouse model of hepatic fibrosis. Using this model, we administered anti-IGFBPrP1 antibody, again via intraperitoneal injection. The morphological changes of liver fibrosis were observed with both HE and Masson stainning. The immunohistochemical assays and Western blotting were used to measure changes in IGFBPrP1, α-smooth muscle actin (α-SMA) and ECM in liver tissues, and the expression of transforming growth factor-β1 (TGF-β1) and Smad3. Data were statistically analyzed using one-way analysis of variance (ANOVA), the SNK-q test for inter-group differences.

RESULTSThe Masson staining analysis showed that compared with normal control group, content of collagen fiber in TAA5w group was significantly increased (P < 0.01), and it was significantly decreased in TAA5w/aIGFBPrP1 group compared with in TAA5w group (P < 0.01). The expression of hepatic IGFBPrP1, α-SMA, TGF-β1, Smad3, collagen I and fibronectin (FN) was significantly up-regulated in the TAA5w group (P < 0.01). Anti-IGFBPrP1 treatment reversed these changes (P < 0.01).

CONCLUSIONSIGFBPrP1 plays an important role in the development of hepatic fibrosis. Anti-IGFBPrP1 prevents fibrosis in mice by suppressing the activation of hepatic stellate cells, inhibiting the synthesis of major components of the ECM (namely, collagen I and FN). The mechanism for this suppression of fibrosis is associated with the TGF-β1/Smad3 signaling pathways.

Actins ; metabolism ; Animals ; Antibodies ; therapeutic use ; Blotting, Western ; Immunohistochemistry ; Insulin-Like Growth Factor Binding Proteins ; immunology ; metabolism ; Liver Cirrhosis ; drug therapy ; metabolism ; Male ; Mice ; Thioacetamide ; toxicity

Actins ; immunology ; metabolism ; Antibodies, Monoclonal ; metabolism ; Child ; Diagnosis, Differential ; Fibroma ; metabolism ; pathology ; surgery ; Follow-Up Studies ; Gastrointestinal Neoplasms ; metabolism ; pathology ; Gastrointestinal Stromal Tumors ; metabolism ; pathology ; Humans ; Leiomyoma ; metabolism ; pathology ; Male ; Pyloric Antrum ; pathology ; Stomach Neoplasms ; metabolism ; pathology ; surgery ; Vimentin ; metabolism

Actins ; metabolism ; Angiomyoma ; metabolism ; pathology ; surgery ; Cranial Fossa, Middle ; Diagnosis, Differential ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Male ; Melanoma-Specific Antigens ; metabolism ; Middle Aged ; Perivascular Epithelioid Cell Neoplasms ; immunology ; S100 Proteins ; metabolism ; Skull Base Neoplasms ; metabolism ; pathology ; surgery

The aim of this study was to investigate the role of RhoA/mDia1 pathway in the process of thrombin-induced platelet aggregation and regulatory effect of PI3K inhibitor on this process. The human platelets were isolated from peripheral blood, the activation of RhoA, Rac1 and Cdc42 in the platelet aggregation was detected by GST pull-down assay and immune co-precipitation, the interaction of RhoA, Rac1 and Cdc42 with mDia1 and the formation of complex in the process of platelet aggregation were determined by immune coprecipitation, and the effect of PI3K inhibitor (wortmannin) on above-mentioned process was assayed. The results showed that thrombin elevated the activity of RhoA and the binding capability of RhoA with mDia1 during thrombin-induced platelet aggregation and spreading on Fg coated coverslips. Wortmannin inhibited the rising of RhoA activity and the binding level of RhoA with mDia1 induced by thrombin. Thrombin elevated the activity of Rac1 and Cdc42 during thrombin-induced platelet aggregation, but could not induce binding of Rac1 or Cdc42 with mDia1. Wortmannin could not inhibit the rising of Rac1 and Cdc42 activity induced by thrombin. It is concluded that the PI3-kinase regulates the thrombin-induced actin cytoskeleton reconstitution in platelets by RhoA-mDia1 pathway.
Actins ; metabolism ; pharmacology ; Adaptor Proteins, Signal Transducing ; immunology ; metabolism ; Blood Platelets ; metabolism ; Cells, Cultured ; Humans ; Phosphatidylinositol 3-Kinases ; pharmacology ; Platelet Aggregation ; drug effects ; Thrombin ; pharmacology ; rac1 GTP-Binding Protein ; metabolism ; rhoA GTP-Binding Protein ; metabolism ; pharmacology

The interactions between the tumor microenvironment and tumor cells determine the behavior of the primary tumors. Whether cancer-associated fibroblasts (CAF) have a tumor progressive or a protective role likely depends on the type of tumor cells and the CAF subpopulation. In the present study, we analyzed the prognostic significance of CAF subpopulations in colorectal cancer (CRC). CAF phenotypes were analyzed in 302 CRC patients by using antibodies against podoplanin (PDPN), alpha-smooth muscle actin (alpha-SMA), and S100A4. The relationship between the CAF phenotypes and 11 clinicopathological parameters were evaluated and their prognostic significance was analyzed from the disease-free and overall survival times. We observed that at the tumor invasive front, PDPN CAFs were present in 40% of the cases, and S100A4 or alpha-SMA CAFs were detected in all the cases. PDPN/S100A4 and alpha-SMA/S100A4 dual-stained CAFs were observed in 10% and 40% of the cases, respectively. The PDPN+ CAFs were associated with 6 favorable clinicopathological parameters and prolonged disease-free survival time. The PDPN-/alpha-SMA(high) CAFs were associated with 6 aggressive clinicopathological parameters and tended to exhibit shorter disease-free survival time. On the other hand, the PDPN-/S100A4(high) CAFs were associated with 2 tumor progression parameters, but not with disease prognosis. The PDPN+ CAF phenotype is distinct from the alpha-SMA or S100A4 CAFs in that it is associated with less aggressive tumors and a favorable prognosis, whereas the PDPN-/alpha-SMA(high) or PDPN-/S100A4(high) CAFs are associated with tumor progression in CRC. These findings suggest that CAFs can be a useful prognostic biomarker or potential targets of anti-cancer therapy in CRC.
Actins/immunology/*metabolism ; Adult ; Aged ; Aged, 80 and over ; Antibodies/immunology ; Carcinoembryonic Antigen/blood ; Colorectal Neoplasms/*diagnosis/mortality/pathology ; Disease-Free Survival ; Female ; Fibroblasts/cytology/metabolism ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Male ; Membrane Glycoproteins/immunology/*metabolism ; Middle Aged ; Neoplasm Staging ; Phenotype ; Prognosis ; S100 Proteins/immunology/*metabolism ; Tumor Markers, Biological/metabolism

AIMTo understand the biological functions of the ectoplasmic specializations between Sertoli cells and maturing spermatids in seminiferous epithelia.

METHODSIn order to disrupt the function of the ectoplasmic specializations, nectin-2, which is expressed at the specialization, was neutralized with anti-nectin-2 antibody micro-injected into the lumen of the mouse seminiferous tubule. Anti-nectin-3 antibody was also micro-injected into the lumen in order to neutralize nectin-3, which is expressed at the specialization.

RESULTSThe actin filaments at the specialization disappeared, and exfoliation of maturing spermatids was observed by electron microscopy.

CONCLUSIONNectin-2 was neutralized by anti-nectin-2 antibody and nectin-3 was neutralized by anti-nectin-3 antibody, respectively. Inactivated nectin-2 and nectin-3 disrupted the nectin-afadin-actin system, and finally the actin filaments disappeared. As a result, the specialization lost the holding function and detachment of spermatids was observed. One of the functions of the specialization seems to be to hold maturing spermatids until spermiation.

Actins ; metabolism ; Animals ; Antibodies ; immunology ; pharmacology ; Cell Adhesion Molecules ; immunology ; metabolism ; Cell Communication ; drug effects ; physiology ; Intercellular Junctions ; drug effects ; metabolism ; Male ; Mice ; Mice, Inbred ICR ; Microfilament Proteins ; metabolism ; Microscopy, Confocal ; Nectins ; Seminiferous Epithelium ; cytology ; drug effects ; metabolism ; Sertoli Cells ; cytology ; drug effects ; metabolism ; Spermatids ; cytology ; drug effects ; metabolism

OBJECTIVETo explore a simplified and reproducible approach for the diagnosis and morphologic prognostication of gastrointestinal stromal tumor (GIST).

METHODSEighty-five cases of gastrointestinal mesenchymal tumors including 74 cases of GIST, 8 esophageal smooth muscle tumor, 1 rectal leiomyosarcoma, 1 Schwannoma, and 1 malignant fibrous histiocytoma were studied by histological evaluation along with an immunohistochemistry panel including vimentin, CD117 (c-kit), CD34, SMA, desmin and S-100. Clinicopathological correlation was performed in 31 cases of GIST that had accompanied with the available follow-up data.

RESULTSAmong 74 GISTs, 34 arose principally from the stomach, 30 from the small intestine, and 10 other cases found in the esophagus, retroperitoneum, mesenterium and omentum. The patients' age ranged from 23 to 80 years (mean 52.5 years), with 45 males and 29 females. Histologically, the tumors composed of either spindle or oval to round cells arranged in interlacing fascicles forming whorls or cellular clusters, cytoplasm generally abundant and eosinophilic. There were 48 cases of spindle cell type, 10 cases of epithelioid cell type and 16 cases of mixed cell type. All 74 cases of GIST were positive for CD117 in a cell membranous pattern, however, some variable staining patterns of CD117 had been noticed in a few cases. In addition, 54 GISTs were also positive for CD34 (72.9%), 25 cases positive for SMA, 5 cases positive for S-100 and 5 cases positive for desmin. According to the Fletcher's scheme, GISTs in this study were divided into 4 subcategories including groups of very low risk of aggressive behavior (3 cases), of low risk (15 cases), of intermediate risk (36 cases) and of high risk (20 cases) respectively. Kaplan-Meier survival analysis of 31 GIST cases whom had been followed up for 16 to 72 months showed a statistically significant difference present among the subcategories (P < 0.01).

CONCLUSIONSGISTs predominantly occur in the middle and old age patients, more common in male, and positive CD117 staining is considered to be the defining marker to differentiate GIST from other mesenchymal tumors of the GI tract. Positive CD34 immun-staining, plus a CD117 positivity, strengthens further a diagnosis of GIST. Subclassification of GISTs using Fletcher's scheme appears to be simple, reproducible, and correlates well with the clinical behavior of the tumor.

Actins ; metabolism ; Adult ; Age Factors ; Aged ; Aged, 80 and over ; Antigens, CD34 ; metabolism ; Disease-Free Survival ; Female ; Follow-Up Studies ; Gastric Mucosa ; pathology ; ultrastructure ; Gastrointestinal Stromal Tumors ; immunology ; pathology ; Humans ; Male ; Middle Aged ; Neoplasm Invasiveness ; Proto-Oncogene Proteins c-kit ; metabolism ; S100 Proteins ; metabolism ; Sex Factors ; Stomach ; pathology