Self-assembled poly(N-methylaniline)-lignosulfonate spheres: from silver-ion adsorbent to antimicrobial material.

Self-assembled poly(N-methylaniline)-lignosulfonate (PNMA-LS) composite spheres with reactive silver-ion adsorbability were prepared from N-methylaniline by using lignosulfonate (LS) as a dispersant. The results show that the PNMA-LS composite consisted of spheres with good size distribution and an average diameter of 1.03-1.27 µm, and the spheres were assembled by their final nanofibers with an average diameter of 19-34 nm. The PNMA-LS composite spheres exhibit excellent silver-ion adsorption; the maximum adsorption capacity of silver ions is up to 2.16 g g(-1) at an adsorption temperature of 308 K. TEM and wide-angle X-ray results of the PNMA-LS composite spheres after absorption of silver ions show that silver ions are reduced to silver nanoparticles with a mean diameter of about 11.2 nm through a redox reaction between the PNMA-LS composite and the silver ions. The main adsorption mechanism between the PNMA-LS composite and the silver ions is chelation and redox adsorption. In particular, a ternary PNMA-LS-Ag composite achieved by using the reducing reaction between PNMA-LS composite spheres and silver ions can be used as an antibacterial material with high bactericidal rate of 99.95 and 99.99% for Escherichia coli and Staphylococcus aureus cells, respectively.

Abnormal expression of Pygopus 2 correlates with a malignant phenotype in human lung cancer.

BACKGROUND: Pygopus 2 (Pygo2) is a Pygo family member and an important component of the Wnt signaling transcriptional complex. Despite this data, no clinical studies investigating Pygo2 expression in lung cancer have yet been reported. METHODS: In the present study, the expression patterns of Pygo2 were evaluated by immunochemistry in 168 patients with non-small cell lung cancer (NSCLC). We used small interfering RNA (siRNA) to specifically silence Pygo2, and investigated its effect on cell growth by an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry analysis in human lung cancer cell lines. RESULTS: Immunohistochemical analysis showed low expression of Pygo2 in normal lung tissues and increased nuclear expression in lung cancer tissues, either with or without perinuclear expression. Abnormal Pygo2 expression was associated with poor differentiation and a high Tumor (T), Node (N) and Metastases (M) stage in NSCLC patients, and correlated with poor prognosis. Using MTT assay we observed that Pygo2 downregulation inhibited cell proliferation; in addition, flow cytometry analysis showed that Pygo2 knockdown induced apoptosis and increased numbers of G1-phase cells and a reduction in S-phase cells. CONCLUSIONS: We therefore conclude that abnormal Pygo2 protein expression may be a marker for advanced NSCLC. Furthermore, Pygo2 knockdown suppresses cell growth.

Slug regulates E-cadherin expression in metastatic adenocarcinoma cells isolated from pleural fluid.

Slug protein is a key regulator of epithelial-mesenchymal transition, but its expression in cancer is less well studied. To evaluate the expression of slug, E-cadherin and vimentin in adenocarcinoma cells from malignant pleural effusions, we analyzed 121 malignant pleural fluid specimens. Twenty-eight nonmalignant pleural fluid specimens were analyzed as control. Besides clinical cytological diagnosis tests, immunofluorescence, immunocytochemistry and Western blotting methods were used. Results showed strong membrane staining of E-cadherin in adenocarcinoma cells from pleural fluid. Slug mainly showed nucleus staining. Cytoplasma positive of vimentin was found in adenocarcinoma cells isolated from pleural fluid. Slug, E-cadherin and vimentin expression was found in 43/121 (36%), 87/121 (72%) and 102/121 (84%) cases, respectively. Our data showed elevated levels of slug were accompanied by down regulation of E-cadherin and the expression of vimentin in adenocarcinoma cells. In addition, there was no relationship between slug expression and patient's age or gender or tumor site. Hyperplasia epithelium cells from nonmalignant pleural fluid were uniformly negative for E-cadherin and slug. In conclusion, the results demonstrated the inverse expression of slug and E-cadherin in the majority of malignant pleural fluid cases compared with nonmalignant pleural fluid. The slug protein may be helpful to access the prognosis of patients with pleural fluid.

Diagnostic utility of MOC-31, HBME-1 and MOC-31 mRNA in distinguishing between carcinoma cells and reactive mesothelial cells in pleural effusions.

OBJECTIVE: To evaluate the individual and combined diagnostic utility of MOC-31, HBME-1 and MOC-31mRNA in the differentiation of adenocarcinoma cells from reactive mesothelial cells in pleural effusions. STUDY DESIGN: To subject the cells from 293 pleural effusions to immunocytochemical staining for MOC-31 and HBME-1 and reverse transcriptase polymerase chain reaction for the expression of MOC-31. RESULTS: MOC-31 and MOC-31mRNA expression were significantly higher in the cancer cell group and in 3 subgrouped as adenocarcinoma, squamous cell carcinoma and small cell lung carcinoma than in the mesothelial cell group, whereas HBME-1 expression was obviously lower in those (p < 0.01). In single use, MOC-31mRNA had the highest sensitivity (90.8%) and accuracy (91.5%), whereas MOC-31 had the highest specificity (100%). When combinations of markers were evaluated together, MOC-31mRNA and HBME-1 gave a high diagnostic performance: sensitivity of 96.7% and accuracy of 95.2%, respectively. CONCLUSION: The detection of MOC-31, HBME-1 and MOC-31-mRNA is helpful in distinguishing between cancer and reactive mesothelial cells in pleural effusions. MOC-31mRNA could be useful to the diagnosis of pleural micrometastasis.

Significance of survivin, caspase-3, and VEGF expression in thyroid carcinoma.

To investigate the clinical significance of survivin, caspase-3, and vascular endothelial growth factor expression in a subset of thyroid carcinoma and their correlation with prognosis. Sixty-eight cases of thyroid carcinoma (TC), 12 cases of thyroid adenoma (TA) and 10 cases of normal thyroid tissue (NT) were involved in immunohistochemical and real-time RT-PCR analyses for survivin, caspase-3, and VEGF expression. Statistical analyses were performed for differential expression among NT, TA and TC, correlations of their expression with the clinicopathological parameters of TC including histological typing, clinical staging and lymphnode metastasis, and relationship of survivin with caspase-3 or VEGF in TC. We observed higher mRNA expression and positive immunostaining for survivin and VEGF in TC compared with TA and NT, with a significant positive correlation among them and significant correlations with histological typing, clinical staging and lymphnode metastasis in TC, but we could not find any significance of caspase-3 in TC and its significant relationship with survivin expression. Our results indicate that survivin and VEGF are unfavorable molecules for TC evolution and prognosis, and possess positive correlation in TC.

[Expression of TNF-like weak inducer of apoptosis (TWEAK) and its relationship to microvessel density in breast cancer].

BACKGROUND & OBJECTIVE: The expression of TNF-like weak inducer of apoptosis (TWEAK) in breast cancer remains disputable. This study was to investigate the expression of TWEAK in breast cancer tissues and breast cancer cell lines with different invasive abilities, and the relationship of TWEAK with microvessel density (MVD). METHODS: Immunohistochemical S-P method was adopted to detect the expression of TWEAK in 70 specimens of breast cancer and 30 specimens of adjacent normal breast tissues. The protein expression of TWEAK was determined by Western blot in a poorly invasive breast cancer cell line MCF-7 and a highly invasive breast cell line MDA-MB-231. Secretion of TWEAK was measured by ELISA assay in MCF-7 and MDA-MB-231 cells. RESULTS: The expression of TWEAK was higher in breast cancer (60%) than in adjacent normal breast tissues( 6.67%) (P<0.05), and is higher in infiltrating ductal carcinoma of the breast (76.67 %) than in breast ductal carcinoma in situ (42.85%) (P=0.003). MVD was higher in infiltrating ductal carcinoma of the breast than in breast ductal carcinoma in situ (P<0.05). The expression of TWEAK was significantly correlated with MVD in infiltrating ductal carcinoma of the breast(r=0.611), but not with breast ductal carcinoma in situ (r=0.015). The expression of TWEAK and secretion of soluble TWEAK were higher in MDA-MB-231 cells than in MCF-7 cells (t=4.259, P=0.007; t=3.6504, P=0.006 ). CONCLUSION: TWEAK expression is related to the metastatic ability of breast cancer.

Induction of apoptosis in osteogenic sarcoma cells by combination of tumor necrosis factor-related apoptosis inducing ligand and chemotherapeutic agents.

BACKGROUND: Osteosarcoma is one of the most common primary malignant tumors of bone with poor prognosis. TNF-related apoptosis inducing ligand (TRAIL) is a member of the tumor necrosis factor (TNF) cytokine family. TRAIL induces apoptosis in various tumor cell lines but is not found to be cytotoxic to many normal cell types in vitro. We investigated the cytotoxic activity of TRAIL and chemotherapeutic agents, including methotrexate (MTX), doxorubicin (DOX) and cisplatin (CDDP), on established osteosarcoma cell line--S-732. METHODS: OS-732 cells were incubated with chemotherapeutic agents MTX, DOX and CDDP at various peak plasma concentrations (PPC), 0.1PPC, 1PPC and 10PPC, alone or with 100 ng/ml of TRAIL for 24 hours or 48 hours. MTT was used to evaluate the cytotoxic activity of different agents on OS-732. The apoptosis proportion was assayed by flow cytometry. Cellular morphologic changes were observed by phase contrast microscope, scan electron microscope, and transmission electron microscope. RESULTS: The inhibitory rate was (24.438 +/- 3.414)% with TRAIL of 100 ng/ml for 24 hours. The cells were responsive to DOX and CDDP with a dose-effect relationship (P < 0.05). In OS-732 cells, DOX and CDDP cooperated synergistically with TRAIL when incubated the cells with them for 24 hours (the combined inhibitory rate is (58.360 +/- 2.146)% and (54.101 +/- 2.721)%, respectively). TRAIL alone or drugs alone induced the apoptosis rate was less than 25% (P < 0.05). However, the combination of TRAIL and MTX did not present synergistic effects on OS-732 cells (P > 0.05, compared with TRAIL alone). CONCLUSIONS: Osteosarcoma OS-732 cells were not responsive to TRAIL-induced apoptosis. DOX and CDDP sensitize osteosarcoma OS-732 cells to TRAIL-induced apoptosis. The combination of TRAIL and MTX presented no synergistic effects on killing OS-732 cells.

[A study on the expression of CASP9 gene and its polymorphism distribution in non-small cell lung cancer].

OBJECTIVE: To explore the expression of caspase 9(CASP9) gene in non-small cell lung cancer (NSCLC) and single nucleotide polymorphism (SNP) distribution of CASP9 in NSCLC patients and normal people. METHODS: Reverse transcription-PCR (RT-PCR) was used to analyze the expression of CASP9 in 81 NSCLC and normal lung tissues. Two SNPs in CASP9 gene were chosen to be investigated. Genotypes of rs1052576 and rs1052571 in 81 NSCLC patients and 100 normal people were analyzed by PCR-restriction fragment length polymorphism (PCR-RFLP). Legally constituted authority statistical analysis was applied to analyze SNP genotype frequency and allele frequency in patients and control group. RESULTS: In comparision with normal lung tissues, CASP9 gene expression was obviously down-regulated in 44.4% (36/81) NSCLC tissues. rs1052571 located in exon 1 of CASP9 gene had no significant difference between two groups, rs1052576 located in exon 5 of CASP9 gene had significant difference between two groups, the G allele frequency in NSCLC patients was higher than those in healthy controls (P< 0.05); the AG genotype frequency in patients with lymph node metastasis was higher than those without lymph node metastasis (P< 0.05). CONCLUSION: This study confirms the association between CASP9 gene and NSCLC oncogenesis, rs1052576 which locates in exon 5 of CASP9 gene is associated with NSCLC. AG genotype has association with lymph node metastasis.