Bovine pulmonary surfactant was obtained by endotracheal lavage of lungs from newly slaughtered calves followed by differential centrifugation.Lipid extracts of bovine surfactant contained 86.1?2.1% "of phospholipids (X?SD) , 1.8?1.1%of protein and smaller amounts of cholesterol, fatty acids, glycerides and carbohydrate. Phosphatidylcholine(83.4?5.6%)accounted for most of the phospholipids, of which disaturated phosphatidylcholine was 76.0? 4.7% .The physicochemical properties of bovine surfactant were measured with a modified Wilhelmy film balance made by the authors.The minimum surface tension was 2.4?1.5mN/m, stability index was 1.78?0.15, surface compresibility at 10mN/m was 0.022?0.004 m/mN, and surface concentration of phospholipids at 10mN/m was 1.112?0.283 nmol/cm2. The surfactant spread rapidly and could be quickly absorbed to the surface of the water.The results show that the bovine pulmonary surfactant we isolated is able to meet the criteria for investigations of surfactant replacement therapy.

Cytokines are involved in both host defense and inflammatory lung injury. Recent work from our laboratory and others has demonstrated that in addition to classical immune cells, lung alveolar epithelial cells (or pneumocytes) can also produce cytokines in response to various stimuli. This new knowledge has advanced our view of the host defense system in the lung. The regulatory mechanisms of cytokine production have been studied in great detail at various cellular and molecular levels, but the mechanisms of intracellular cytokine transport are largely unknown. Our recent studies suggest that the cytoskeleton could play an important role in mediating intracellular cytokine trafficking. This could be an important regulatory step for cytokine production. For example, lipopolyssacharide (LPS) induced tumor necrosis factor-α (TNF-α) from rat pneumocytes, which was further enhanced by a microfilament-disrupting agent. LPS also induced macrophage inflammatory protein-2(MIP-2), a chemokine for neutrophil recruitment and activation, from rat pneumocytes. This effect was enhanced by microtubule-disrupting agents. We speculate that both microfilaments and microtubules are involved in regulating cytokine transportation in pneumocytes through different mechanisms. Further investigation in on going in my laboratory. From a clinical perspective, if we understand the mechanisms regulating cytokine production and release from lung alveolar epithelial cells, we may be able to enhance or inhibit release of crucial cytokines depending on the clinical situation.

Cytokines can have either pro-or anti-inflammatory activity and immunosuppressive activity,depending on the microenvironment.Tumors contain immune cells and a network of pro-and anti-inflammatory cytokines,which collaborate in the development and progression of cancer.Cytokine might prove to be prognostic.The systemic effects of pro-inflammatory cytokines are associated with fatigue,depression,cognitive impairment,anorexia,cachexia,pain,toxicity of treatment and resistance to treatment,which can affect quality of life.

Objective: To investigate the relationship of nm23 and VEGF expression with hilar lymph node micrometastasis and the prognosis of stage Ⅰ non-small cell lung cancer (NSCLC). Methods: Immunohisto-chemistry was used to detect nm23 and VEGF protein expression in primary cancer tissue and cytokeratins in 86 hilar lymph nodes from 40 patients with stage Ⅰ NSCLC. Kaplan-meier method and Log rank test were used to analyze the 5-year survival. Results: The rate of positive hilar lymph node micrometastasis was 12.5% for stage Ⅰ NSCLC. Lymph node micrometastasis was not statistically correlated with gender, age, histologic type, differentiation, primary tumor size or VEGF protein expression (P>0.05). But it was reversely associated with nm23 protein expression in primary cancer tissue of NSCLC (P<0.05). The 5-year overall survival of pa-tients with well-differentiated NSCLC, positive nm23 expression and negative lymph node micrometastasis was better than those with moderately and poorly differentiated NSCLC, negative nm23 expression and posi-tive lymph node micrometastasis (P<0.05). Lymph node micrometastasis and nm23 protein expression were identified as two independent prognostic factors for stage Ⅰ NSCLC by univariate Cox regression analysis.Conclusion: nm23 protein expression in pdmary cancer tissue of stage Ⅰ NSCLC is closely associated with hi-lar lymph node micrometastasis, nm23 protein and hilar lymph node micrometastasis are two independent prognostic factors for stage Ⅰ NSCLC. Patients with nm23 protein deletion and positive lymph node microme-tastasis have a poor prognosis.

TheKRAS gene is frequently mutated in multiple cancer types, but it fell off the drug discovery radar for many years because of its inherent “undruggable” structure and undeifned biological properties. As reported in the paper entitled “Suppression of KRas-mutant cancer through the combined inhibition of KRAS with PLK1 and ROCK” inNature Com-munications, we performed a synthetic lethal screening with a combinatorial strategy on a panel of clinical drugs; we found that combined inhibition of polo-like kinase 1 and RhoA/Rho kinase markedly suppressed tumor growth in mice. An increase in the expression of the tumor suppressor P21WAF1/CIP1 contributed to the synergistic mechanism of the combination therapy. These ifndings open a novel avenue for the treatment ofKRAS-mutant lung cancer.

Objective To study the expression characteristics of Let-7 genes in breast cancer.Methods Twenty-eight patients with breast cancer were randomly selected,and their cancer tissue and adjacent normal tissue were collected.TRIzol was used to extract the total RNA and real-time quantitative PCR was used to detect the relative gene expression levels.Results The expression of precursor Let-7 in cancer tissue was (9.65 ± 2.31),which was lower than that in normal tissue (10.05 ± 2.81),P =0.048.Precursor Let-7 had dependence relationship with the long menstruation (b =0.816,P =0.029).The menarche age showed a positive correlation with precursor Let-7 in normal tissue (r =0.502,P =0.048) and a negative correlation in cancer tissue (r =-0.484,P =0.049) Conclusions The expression of precursor Let-7 in cancer tissue is lower than that in normal tissue.The period of menstruation is a protective factor to breast cancer.

AIM: To construct a mouse IFN-? expression vector and observe the antitumor effects of mouse peritoneal macrophages transfected with IFN-? in vivo and in vitro. METHODS: The IFN-? mRNA was amplified by RT-PCR. The open reading frame of mouse IFN-? gene was recombinanted with eukaryotic expression vector pcDNA3.1 through subcloning. Mouse peritoneal macrophages were transfected with recombinant vector pcDNA3.1-IFN-?. The expression of INF-? mRNA was measured by RT-PCR. Another group of peritoneal macrophages were cultured with the culture medium from pcDNA3.1-IFN-? transfecting groups, and its antitumor effect was measured by MTT. pcDNA3.1-IFN-? plasmid was peritoneally injected inte mouse with tumor. The appearance of ascites of pcDNA3.1-IFN-? plasmid injected mice and survival time were observed. RESULTS: The mouse IFN-? expression vector pcDNA3.1-IFN-? was constructed. The sequence was demonstrated to be the same as on GenBank. The recombinant vector was introduced into mouse peritoneal macrophages. IFN-? mRNA was detected by RT-PCR. The supernatant from cultured macrophages transfected with pcDNA3.1-IFN-? plasmid stimulated the antitumor effects of the macrophages without transfection. The appearance of ascites in pcDNA3.1-IFN-? plasmid injected mouse was delayed and survival time was longer than that in other groups. CONCLUSION: We have successfully constructed the mouse IFN-? expression vector pcDNA3.1-IFN-?. Mouse peritoneal macrophages transfected with pcDNA3.1-IFN-? have antitumor effects in vivo and in vitro.

Insulin resistance in insulin sensitive organ results in metabolic disorder such as hyperglycemia, hyperinsulinemia and hyper triglyceridemia which are common features of type 2 diabetes.Insulin resistance in liver cells mainly causes impaired glycogen synthesis, failed to suppress glucose production which is the major contribution to hyperglycemia.FGF-21 as a new metabolic regulator can control fasting blood glucose.The mechanism of FGF-21 effects on regulating plasma glucose has little to known.In order to establish an in vitro insulin resistant model of liver cells and evaluate the effects and mechanism of FGF-21 on glucose metabolism in the cell model, HepG2 cells were incubated with 10-7 mol/L insulin for 24 h to build insulin-resistant cell model.To evaluate the cells for insulin resistance, the cells were stimulated with fresh insulin for 24 h and the glucose uptake by these cells was carried out.The insulin-resistant cells were treated with different concentrations of FGF-21 for 24 h and insulin-treated cells were used as a control.The glucose uptake by the cells was detected by the method of glucose oxidizes/peroxides(GOD-POD);the synergy between insulin and FGF-21 was evaluated.The mRNA expression of GLUT1 in the insulin-resistant cells was detected by the real-time PCR.Glycogen synthesis of the cells was examined by the anthrone method.The results showed that HepG2 cells treated with 10-7 mol/L insulin for 24 h became resistant to insulin and the insulin resistance status was maintained for 48 h without change of cell morphology.FGF-21 could stimulate glucose consumption of the insulin-resistant model in a dose-dependent manner.The glucose consumption and glycogen synthesis of the insulin-resistant model were significantly improved by FGF-21 treatment.FGF-21 showed strong synergy with insulin in glucose uptake and glycogen synthesis of the model cells.While the cells became resistant to insulin, FGF-21 could increase the mRNA expression of GLUT1.Thus, It is concluded that FGF-21 stimulates glucose uptake in insulin resistant HepG2 cells through GLUT1 expression, stimulates glycogen synthesis and improves the glucose metabolism in the insulin resistant liver cell model.

Fibroblast growth factor-21 (FGF-21) is an important metabolism regulator, however, whether FGF-21 has effects on cardiovascular remains unclear. In this study, H2O2-induced injury in H9c2 cells was used as a cell model, the anti-apoptosis potential and mechanism of FGF-21 against oxidative injury were evaluated by MTT assay, flow cytometry assay and real-time PCR. The results showed that FGF-21 could increase the cell survival of H2O2-induced injury in H9c2 cells and prevent H9c2 cells from oxidative stress-induced apoptosis. Furthermore, FGF-21 can elevate SOD activity and regulate Bcl-2/Bax expression in H9c2 cells. The results suggest that FGF-21 have protective effect against the H2O2-induced apoptosis in H9c2 cells.

AIM:To study the effect of p21-activated protein kinase 2 (PAK2) knockdown by RNA interfer-ence on the proliferation and apoptosis of human breast cancer cells .METHODS:The short hairpin RNA ( shRNA) targe-ting PAK2 gene was designed and used for packing lentivirus in 293T cells.Human breast cancer MCF-7 cells were infected by the virus particles and PAK2 knockdown stable cell line was established by puromycin selection .The knockdown effi-ciency was assessed by Western blotting .The proliferation ability of MCF-7 cells was evaluated by CellTiter 96 AQueous and anchorage-independent growth assays .The cell apoptosis induced by staurosporine was detected by flow cytometry . RESULTS:The protein level of PAK2 was significantly suppressed after silencing of PAK2 gene in MCF-7 cells ( P<0.01).Furthermore, knockdown of PAK2 caused remarkable inhibition of the cell proliferation and colony formation (P<0.01).Staurosporine induced more apoptosis in the PAK2 knockdown cells compared with the control cells (P<0.01). CONCLUSION:Knockdown of PAK2 inhibits the proliferation of MCF-7 cells and increases the sensitivity of chemothera-peutic drug-induced cell apoptosis , suggesting that PAK2 might be a new therapeutic target in breast cancer treatment .