OBJECTIVETo evaluate the change in protein expression of peroxiredoxin I (Prx I) during pulmonary fibrosis among rats exposed to silica dust and to investigate the role of Prx I in pulmonary fibrosis.

METHODSNinety male Wistar rats were randomly divided into control group (n = 60) and experimental group (n = 30). The control group received intratracheal perfusion of saline (1 ml), while the experimental group received intratracheal perfusion of suspension of silica dust (50 mg/ml) to establish a rat model of silicosis. At 1, 2, 3, 4, 6, or 8 weeks after treatment, 10 rats in control group and 5 rats in experimental group were sacrificed. The lung tissues were collected for conventional pathological observation. The protein expression of Prx I at each time point was measured by immunohistochemistry and Western blot.

RESULTSAmong the rats exposed to silica dust, Prx I was seen in the form of brown particles that were mainly distributed in the alveolar septa and the cytoplasm of alveolar epithelial cells, macrophages, vascular endothelial cells, and smooth muscle cells around the blood vessels and tracheae. The control group showed weak protein expression of Prx I, and the experimental group had significantly higher protein expression of Prx I than the control group at all time points (P < 0.05). In the experimental group, the protein expression of Prx I was upregulated significantly at 1 and 2 weeks and decreased at 3∼8 weeks.

CONCLUSIONThe change in protein expression of Prx I may be one of the important causes of the onset and development of pulmonary fibrosis in rats exposed to free silica.

Animals ; Disease Models, Animal ; Lung ; enzymology ; pathology ; Male ; Peroxiredoxins ; metabolism ; Pulmonary Fibrosis ; enzymology ; pathology ; Rats ; Rats, Wistar ; Silicon Dioxide ; toxicity ; Silicosis ; enzymology ; pathology

We assessed the effects of furan and lycopene on the histopathological and biochemical changes on lungs, body and lung weights, and food consumption of rats. Furan and diabetes caused histopathological changes, increment in malondialdehyde levels, and decrease in antioxidant enzyme activities. Lycopene showed a protective effect against these damages, except for glutathione-S-transferase and glutathione peroxidase activities. Consequently, furan and diabetes resulted in lung toxicity. Our findings demonstrate that furan treatment resulted in more alterations in histology and biochemical parameters in diabetic rats and lycopene showed protective effects against these alterations.
Animals ; Antioxidants ; pharmacology ; Carotenoids ; pharmacology ; Diabetes Mellitus, Experimental ; enzymology ; pathology ; Furans ; toxicity ; Lung ; drug effects ; enzymology ; pathology ; Male ; Rats, Wistar

OBJECTIVETo investigate DNA-dependent protein kinase catalytic subunit (DNA-PKcs) content and activity in lung adenocarcinoma cell lines and its correlation with radiosensitivity.

METHODSThe content and activity of DNA-PKcs were analyzed in two lung adenocarcinoma cell lines A549 and H1299 by Western blotting and the Signa TECT DNA-PK assay kit. The dose-survival relationship for two cell lines was analyzed using clonogenic formation assay.

RESULTSA549 was more radiosensitive than H1299. The survival fractions at 2 Gy (SF2) were 0.7412 in A549 cell line and 0.2473 in H1299 cell line. The content of DNA-PKcs was significantly higher in A549 cells than in H1299 cells (t=10.37, P<0.001). The integrated optical densities were 3.29-/+0.44 in A549 cells and 0.50-/+0.17 in H1299 cells. DNA-PKcs activities in A549 and H1299 cells were 8.29-/+1.37 and 2.47-/+1.09, respectively, showing a significant difference between them (t=5.76, P=0.005).

CONCLUSIONDNA-PKcs is an important factor to affect the radiosensitivity of lung adenocarcinoma cell lines.

Adenocarcinoma ; enzymology ; pathology ; Calcium-Binding Proteins ; genetics ; metabolism ; Cell Line, Tumor ; Humans ; Lung Neoplasms ; enzymology ; pathology ; Radiation Tolerance

Crystallization ; Eosinophils ; enzymology ; Fascioliasis ; pathology ; Granuloma ; pathology ; Humans ; Liver ; pathology ; ultrastructure ; Lung ; pathology ; ultrastructure ; Lung Diseases, Parasitic ; pathology ; Lysophospholipase ; metabolism ; Paragonimiasis ; pathology

OBJECTIVETo investigate the expression of tripartite-motif protein 25 (TRIM25) and pyruvate kinase M2 (PKM2) protein in non-small cell lung cancer (NSCLC) and explore their role in the occurrence and progression of NSCLC.

METHODSThe expressions of TRIM25 and PKM2 protein were detected in 60 NSCLC specimens and 20 adjacent normal lung tissue (>5 cm from the lesions) with immunofluorescence histochemical method and in 10 fresh specimens of NSCLC with Western blotting. The results were analyzed in relation with the clinicopathological features of the patients.

RESULTSThe positivity rates of TRIM25 expression was 45% in the 60 lung carcinoma specimens, significantly higher than that in the 20 normal lung tissues (10%, P=0.005). TRIM25 protein was expressed in 28.6% of lung adenocarcinoma tissues and in 59.4% of squamous carcinoma tissues (P=0.017). TRIM25 protein expression was positively correlated with the TNM stages and lymph node metastasis of NSCLC (P<0.05). The expressions of PKM2 protein in 60 cases of lung carcinoma was 73.3%,while in 20 cases of normal lung tissues the expressions was 30%(P=0.001). The positivity rates of PKM2 expression differed significantly between lung adenocarcinoma and squamous carcinoma (57.1% vs 87.5%, P=0.008). An inverse correlation was noted between TRIM25 and PKM2 expressions (P=0.026).

CONCLUSIONTRIM25 and PKM2 protein may participate in the occurrence and progression of NSCLC, and their expressions are inversely correlated.

Adenocarcinoma ; enzymology ; Carcinoma, Non-Small-Cell Lung ; enzymology ; Carcinoma, Squamous Cell ; enzymology ; Carrier Proteins ; metabolism ; Humans ; Lung ; pathology ; Lung Neoplasms ; enzymology ; Lymphatic Metastasis ; Membrane Proteins ; metabolism ; Thyroid Hormones ; metabolism ; Transcription Factors ; metabolism ; Tripartite Motif Proteins ; Ubiquitin-Protein Ligases ; metabolism

OBJECTIVETo evaluate the application of traditional cytomorphology, telomerase activity analysis and immunocytochemistry in cytopathologic diagnosis of pleural effusion and bronchoalveolar lavage samples.

METHODSA total of 123 agar-paraffin double-embedded pleural effusion and bronchoalveolar lavage fluid samples were enrolled into study. The cytomorphologic features were reviewed and correlated with immunocytochemical findings and telomerase activity.

RESULTSTelomerase activity was detected in 53 specimens using the real-time telomeric repeat amplification protocol. Amongst the cases studied, 39 samples (31.7%) contained overtly malignant cells while 20 cases (16.0%) were equivocal by conventional cytology. After verification by immunocytochemistry and clinical follow-up data, the diagnostic accuracy of telomerase activity and cytology was 87.0% and 82.1%, respectively. The sensitivity (97.6%) and specificity (100.0%) of cytology examination, when combined with telomerase activity analysis, were greater than those of cytology examination or telomerase activity analysis alone.

CONCLUSIONSTelomerase activity analysis can be used as an adjunctive investigative tool in cytology assessment of pleural effusion and bronchoalveolar lavage samples. The diagnostic accuracy can be further improved with the application of immunocytochemistry on agar-paraffin double-embedded cell block tissues.

Breast Neoplasms ; diagnosis ; enzymology ; pathology ; Bronchoalveolar Lavage Fluid ; chemistry ; Female ; Follow-Up Studies ; Humans ; Immunohistochemistry ; Lung Neoplasms ; diagnosis ; enzymology ; pathology ; Pleural Effusion ; diagnosis ; enzymology ; pathology ; Pleural Effusion, Malignant ; diagnosis ; enzymology ; pathology ; Sensitivity and Specificity ; Telomerase ; metabolism

OBJECTIVETo study the effects of neuron specific enolase (NSE) gene silencing on the cell proliferation and apoptosis of lung cancer cells in vitro.

METHODSNSE protein expression was detected in human small cell lung cancer cell line NCI-H446 and non-small cell lung cancer cell line A549 by immunocytochemistry, and a small interference RNA (siRNA) was transfected into the cells to inhibit NSE gene expression. The changes in the cell cycle, apoptosis, Ki67 protein and caspase-3 activity in the transfected cells were observed by flow cytometry, Western blotting and colorimetric assay, respectively.

RESULTSBoth A549 and NCI-H446 cells expressed NSE protein. Transfection of siRNA for NSE gene significantly inhibited the expression of NSE gene in the cells, resulting in an inhibition rate exceeding 90%. NSE gene silencing caused significantly decreased cell percentage in S phase and the expression of Ki67 protein, and increased the cell apoptotic rate and caspase-3 activity.

CONCLUSIONNSE gene expression promotes the cell proliferation and inhibits the cell apoptosis in lung cancer cells with neuroendocrine differentiation, which might be a causative factor contributing to increased malignancy of the cells.

Adenocarcinoma ; enzymology ; genetics ; pathology ; Apoptosis ; genetics ; Caspase 3 ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Ki-67 Antigen ; metabolism ; Lung Neoplasms ; enzymology ; genetics ; pathology ; Phosphopyruvate Hydratase ; genetics ; RNA Interference ; Small Cell Lung Carcinoma ; enzymology ; genetics ; pathology

OBJECTIVETo determine the cut-off value of serum neuron-specific enolase (NSE) level for distinguishing small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC).

METHODSSerum NSE levels were measured by enzyme-linked immunosorbent assay in 137 patients with NSCLC or SCLC, and the best cut-off value was analyzed using ROC curve.

RESULTSThe positivity rate of serum NSE was significantly higher in patients with SCLC than in those with NSCLC (P<0.01). The best cut-off value was 15.45 microg/L using ROC curve, which gave a sensitivity of 66.7% and specificity of 65.7%.

CONCLUSIONSerum NSE level may allow simple and cost-effective differentiation of SCLC and NSCLC.

Biomarkers, Tumor ; blood ; Carcinoma, Non-Small-Cell Lung ; enzymology ; pathology ; Carcinoma, Small Cell ; enzymology ; pathology ; Diagnosis, Differential ; Female ; Humans ; Lung Neoplasms ; enzymology ; pathology ; Male ; Middle Aged ; Phosphopyruvate Hydratase ; blood

OBJECTIVE: To explore the changes of apoptosis of cells in the lung tissue of rats with silica instillation and to its significance in silicosis, and to clarify the role of caspase-3 in the apoptosis progress. METHODS: Forty-eight rats were randomly divided into saline control groups and silica instillation groups, and the silicosis model was established in rats. Flow cytometry was used for detecting the rate of apoptosis at various stages. Immunohistochemistry for the expression of cleaved caspase-3. RESULTS: The model of rat silicosis was established successfully. The apoptosis rate in the experimental group was significantly higher than that in the control group, and was increased with time. Caspase-3 was mainly expressed in alveolar epithelium cells, pulmonary macrophages and infiltrated inflammation cells. The expression of caspase-3 in the experimental group was stronger than that in the control group, but its expression intensity was not related to the cell apoptosis (r = 0.215, P > 0.05). CONCLUSION The apoptosis of the lung cells plays an important role during rat silicosis genesis. Caspase-3 plays an important role in regulating cell apoptosis during rat silicosis genesis.
Animals ; Apoptosis ; physiology ; Caspase 3 ; Caspases ; metabolism ; Lung ; enzymology ; pathology ; Male ; Pulmonary Fibrosis ; etiology ; pathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Silicosis ; enzymology ; pathology

OBJECTIVETo investigate the effect of DNA methyltransferases 1 (DNMT-1) inhibition on the ACC-M cells in vitro and in vivo and discuss the role of DNMT-1 in the development, invasion and metastasis of salivary adenoid cystic carcinoma (SACC).

METHODSACC-M cells of stable DNMT-1 inhibition were established in a previous research. In vitro, the growth and invasion of ACC-M cells which stably inhibited DNMT-1 were detected and analyzed by methyl thiazolyl tetrazolium (MTT) growth curve, flow cytometry, plating efficiency and invasion assay. In vivo, the growth and metastasis of ACC-M cells which persistently inhibited DNMT-1 were observed and analyzed by subcutaneous injection and tail vein injection into the nude mice.

RESULTSIn vitro, the doubling time [(34.7 +/- 2.1) h], S phase fraction [(17.4 +/- 1.7)%], plating efficiency [(43.0 +/- 1.3)%] of ACC-M cells was significantly different from those of blank [(26.2 +/- 3.1) h, (31.5 +/- 2.0)%, (71.0 +/- 4.7)%], empty load control [(28.4 +/- 3.9) h, (39.0 +/- 2.0)%, (66.0 +/- 5.2)%], P < 0.05, and the invasion ability was not significantly different among these groups (P > 0.05). In vivo, the subcutaneous tumor forming rate (6/10), volume [(2.18 +/- 0.83) mm(3)], weight [(0.0156 +/- 0.0046) g] of ACC-M cells was also significantly lower than that of blank [10/10, (155.44 +/- 1.67) mm(3), (0.0724 +/- 0.0157) g], empty load control [10/10, (147.46 +/- 1.73) mm(3), (0.0729 +/- 0.0177) g], P < 0.05, but the rate of lung metastasis was not significantly different among these groups (P > 0.05), and the masses (2.0 +/- 0.5), diameter (70.0 +/- 20.3) microm of ACC-M cells was significantly lower than that of blank [(28.0 +/- 5.5), (195 +/- 25.4) microm], empty load control [(27.0 +/- 4.5), (190.0 +/- 19.9) microm], P < 0.05.

CONCLUSIONSInhibition of DNMT-1 is able to inhibit the proliferation and metastasis of ACC-M cells in vitro and in vivo.

Animals ; Carcinoma, Adenoid Cystic ; enzymology ; pathology ; secondary ; Cell Line, Tumor ; Humans ; Lung Neoplasms ; secondary ; Mice ; Mice, Nude ; Neoplasm Invasiveness ; Repressor Proteins ; antagonists & inhibitors ; Salivary Gland Neoplasms ; enzymology ; pathology