Simple, clean preparation method for cross-linked α-cyclodextrin nanoparticles via inclusion complexation

A simple, clean method was presented in this letter to prepare cross-linked α-cyclodextrin (α-CD) nanoparticles with a low dispersion. The nanoparticles were synthesized in water by cross-linking the inclusion complex of α-CDs and poly(ethylene glycol) (PEG). The structure of the nanoparticles was characterized by (1)H NMR, nuclear overhauser enhancement spectroscopy (NOESY), and wide-angle X-ray diffraction (XRD). Spherical morphology was observed by scanning electron microscopy (SEM) for these nanoparticles. Their average hydrodynamic radius was determined to be 67 nm by dynamic light scattering (DLS). Small guest molecules could be included in the cross-linked α-CD nanoparticles, and anticancer drug cisplatin was used to evaluate the drug release behavior.

Informative SNPs selection based on two-locus and multilocus linkage disequilibrium: criteria of max-correlation and min-redundancy

Currently, there are lots of methods to select informative SNPs for haplotype reconstruction. However, there are still some challenges that render them ineffective for large data sets. First, some traditional methods belong to wrappers which are of high computational complexity. Second, some methods ignore linkage disequilibrium that it is hard to interpret selection results. In this study, we innovatively derive optimization criteria by combining two-locus and multilocus LD measure to obtain the criteria of Max-Correlation and Min-Redundancy (MCMR). Then, we use a greedy algorithm to select the candidate set of informative SNPs constrained by the criteria. Finally, we use backward scheme to refine the candidate subset. We separately use small and middle (>1,000 SNPs) data sets to evaluate MCMR in terms of the reconstuction accuracy, the time complexity, and the compactness. Additionally, to demonstrate that MCMR is practical for large data sets, we design a parameter w to adapt to various platforms and introduce another replacement scheme for larger data sets, which sharply narrow down the computational complexity of evaluating the reconstruct ratio. Then, we first apply our method based on haplotype reconstruction for large size (>5,000 SNPs) data sets. The results confirm that MCMR leads to promising improvement in informative SNPs selection and prediction accuracy.

An integrated model of substrate clogging in vertical flow constructed wetlands

This paper presents an integrated model of substrate clogging in a vertical flow constructed wetland (VFCW). The model simulates the reduction of pore space in the wetland substrate due to combined influences of various physical, biogeochemical and plant-related processes. A series of experiments based on laboratory-scale VFCWs were conducted to examine and measure key parameters related to clogging of the wetland substrate during operation under different conditions. The model was then validated using data collected from the experiments. The results showed that the model was able to replicate the clogging phenomenon as observed in the experiments, in particular, the characteristic clogging time. The model also predicted well individual contributions to clogging by accumulated inert suspended solids, microbial biomass and plant root materials during the wetland operation. Although the validation was based on the laboratory data, the results indicated that the model describes well the processes underlying the clogging and has the potential to become a tool for assessing the performance of prototype CWs in relation to clogging at both the design and operation stages.

Up-regulation of MBD1 promotes pancreatic cancer cell epithelial-mesenchymal transition and invasion by epigenetic down-regulation of E-cadherin

Methyl-CpG binding domain protein 1 (MBD1) has been implicated in transcriptional regulation, heterochromatin formation, genomic stability, cell-cycle progression and development. It is also predicted that MBD1 might be involved in tumor development and progression. However, whether and how MBD1 is involved in tumorigenesis, especially in pancreatic cancer (PC), is currently unknown. We found that MBD1 was significantly up-regulated in PC tissues compared with the surrounding normal tissues according to RT-PCR data. Tissue microarray (TMA) based immunohistochemical study from 58 surgically resected PC specimens indicated that higher MBD1 expression correlated with lymph node metastasis and poor survival in PC patients. Gain- and loss-of-function studies in vitro validated MBD1 as a potent oncogene promoting PC cell invasion as well as epithelial-mesenchymal transition (EMT). Mechanistically, MBD1 is associated with Twist and NAD-dependent deacetylase sirtuin-1 (SIRT1), thereby forming the Twist-MBD1-SIRT1 complex on the CDH1 promoter, which resulted in reduced E-cadherin transcription activity and increased cell EMT ability. Significantly, targeting MBD1 reversed the EMT phenotype of PC and restored sensitivity to chemotherapy. Taken together, the results of our study revealed a novel function of MBD1 in PC invasion and metastasis by providing a molecular mechanism underlying MBD1-promoted EMT. Thus MBD1 may serve as a potential therapeutic target for PC.

A retrospective study of different treatments of limited-stage small-cell esophageal carcinoma and associated prognostic factor analysis

Primary, small-cell esophageal carcinoma (SCEC) is a rare but highly malignant tumor. Due to lack of randomized, controlled, prospective studies, there are currently no unified treatment modalities for SCEC. This study retrospectively analyzed the outcomes of different treatments and prognostic factors that influence overall survival in patients with limited-stage SCEC. The study included 106 patients pathologically diagnosed with limited-stage SCEC at Huai'an First People's Hospital, Nanjing Medical University (Huai'an, China), between 1998 and 2007. There were 66 males and 40 females, with a median age of 58 years (range: 45-77 years). Fourteen patients received surgery alone, 42 received surgery and postoperative chemotherapy, 11 received radiotherapy alone, and 39 received concurrent chemoradiotherapy. Combined modality treatment with and without chemotherapy yielded 5-year survival rates (5YSRs) of 27.2% and 0%, respectively. Associated median survival times were 22 months and 11 months, respectively, with a hazard ratio (HR) of 2.30 (95% confidence interval [CI]: 1.42-3.73, P = 0.001). Among patients treated with surgery plus postoperative chemotherapy or with concurrent chemoradiotherapy, the 5YSRs were 31.0% and 23.1%, respectively. Median survival times were 26 months and 18 months, with an HR of 1.25 (95% CI: 0.75-2.09, P = 0.725). Multivariate survival analysis using Cox regression model showed that chemotherapy was a positive independent prognostic factor for SCEC (HR 2.92, 95% CI: 1.25-6.80). Chemotherapy-based combined modality treatment appears to increase the long-term survival of patients with limited-stage SCEC. Similar overall survival rates results are achieved with surgery combined with chemotherapy as with concurrent chemoradiotherapy, with chemotherapy being an independent prognostic factor. Randomized, controlled, prospective studies are needed to identify optimal chemotherapy regimens for treating SCEC.

Effects of dietary forage sources on rumen microbial protein synthesis and milk performance in early lactating dairy cows

The objective of this study was to evaluate the effects of dietary forage sources on milk performance, rumen microbial protein synthesis, and N utilization in early lactation dairy cows. Twelve primiparous Chinese Holstein dairy cows (45 ± 6.0 DIM) were used in a 3 × 3 Latin square design. Diets were isonitrogenous and isocaloric, with a forage-to-concentrate ratio of 45:55 [dry matter (DM) basis] and contained similar concentrate mixtures. Different forage sources were then added (on a DM basis): 21% corn silage, 19% corn stover, and 5% alfalfa hay (CS); 19% corn silage, 21% Chinese wild rye hay and 5% alfalfa hay (CWR); or 19% corn silage, 9% Chinese wild rye hay, and 17% alfalfa hay (AH). Each period lasted for 21 d, with the first 14 d for an adaptation period. Dry matter intake was not affected by the source of dietary forage. Milk yield was higher for cows fed AH than those fed CS, with an intermediate value for CWR. Milk protein content was higher in the cows fed AH compared with CWR (3.02 vs. 2.92%), with CS (2.95%) at an intermediate position. The contents of milk fat and lactose were not different among the treatments. However, milk efficiency (milk yield/DM intake) was higher for cows fed AH than those fed CS, with those fed CWR intermediate. Cows fed AH had higher microbial protein yield and metabolizable protein than those fed CS or CWR. The concentrations of urea N in the urine, blood, and milk were decreased for cows fed AH, indicating an increased N conversion. The results indicated that corn stover could replace Chinese wild rye grass in the diets for lactating cows and that a high proportion of alfalfa hay in the diet is beneficial for milk protein production by increasing microbial protein yield. This can be attributed to the improving the supply of rumen-available energy.

Left atrial and right atrial deformation in patients with coronary artery disease: a velocity vector imaging-based study

Background

Impaired left ventricular (LV) function has been shown by strain rate (SR) imaging in patients with coronary artery disease (CAD). Our aim was to investigate global and regional, systolic and diastolic left atrial (LA) and right atrial (RA) longitudinal deformation in CAD using velocity vector imaging.

Methods

Echocardiographic and velocity vector imaging studies were performed in 20 patients with mild CAD, 40 patients with severe CAD and 25 controls. Maximal atrial volume, peak atrial longitudinal strain (ε_s) and SR during LV systole (SRs), SR during early LV filling (SRe) and late LV filling (SRa) were measured. Longitudinal strain during atrial contraction (ε_a) was obtained at the onset of P-wave on electrocardiography, and ε_a/ε_s was calculated.

Results

Longitudinal peak ε_s and SRs of LA showed decreased trend among CAD patients. The global and lateral LA SRe were prominently lower, while RA ε_a, SRa and ε_a/ε_s were prominently higher in 2 CAD groups than control group (P value <0.05). As compared with controls and patients with other single-vessel disease, LA SRa and ε_a/ε_s ratio were significantly increased among patients with exclusively left anterior descending coronary artery (LAD) stenosis (SRa 1.14±0.38 s⁻¹, 1.10±0.41 s⁻¹, 1.45±0.46 s⁻¹, P value<0.05; ε_a/ε_s 0.44±0.11, 0.44±0.20, 0.57±0.12, P value<0.01).

Conclusions

Apparently decreased SRe of LA and increased ε_a, SRa and ε_a/ε_s of RA were found in CAD patients with preserved LVEF and E/E' in gray zone. SRa and ε_a/ε_s of LA were found to significantly increase in those with LAD stenosis.

PTBP1-dependent regulation of USP5 alternative RNA splicing plays a role in glioblastoma tumorigenesis

Aberrant RNA splicing is thought to play a key role in tumorigenesis. The assessment of its specific contributions is limited by the complexity of information derived from genome-wide array-based approaches. We describe how performing splicing factor-specific comparisons using both tumor and cell line data sets may more readily identify physiologically relevant tumor-specific splicing events. Affymetrix exon array data derived from glioblastoma (GBM) tumor samples with defined polypyrimidine tract-binding protein 1 (PTBP1) levels were compared with data from U251 GBM cells with and without PTBP1 knockdown. This comparison yielded overlapping gene sets that comprised only a minor fraction of each data set. The identification of a novel GBM-specific splicing event involving the USP5 gene led us to further examine its role in tumorigenesis. In GBM, USP5 generates a shorter isoform 2 through recognition of a 5' splice site within exon 15. Production of the USP5 isoform 2 was strongly correlated with PTBP1 expression in GBM tumor samples and cell lines. Splicing regulation was consistent with the presence of an intronic PTBP1 binding site and could be modulated through antisense targeting of the isoform 2 splice site to force expression of isoform 1 in GBM cells. The forced expression of USP5 isoform 1 in two GBM cell lines inhibited cell growth and migration, implying an important role for USP5 splicing in gliomagenesis. These results support a role for aberrant RNA splicing in tumorigenesis and suggest that changes in relatively few genes may be sufficient to drive the process.

[Establishment and their biological characteristics of clonal cell subpopulations (NL9980 and L9981) from a human lung large cell carcinoma cell line (WCQH-9801)]

BACKGROUND

To explore the possibility of separating and establishing clonal cell subpopulations with different metastatic phenotype from a human lung large cell carcinoma cell line (WCQH-9801), to identify the difference of biological and molecular biology between NL9980 and L9981 cell lines.

METHODS

Two sub-cell lines (NL9980 and L9981) were isolated and established from a human lung large cell carcinoma cell line (WCQH-9801) by the single cell cloning techniques. The RELP, mRNA and protein transcript expression were detected in NL9980 and L9981 cell lines by Southern blot, RT-PCR and Western blot. The biological characteristics of vivo and vitro were determined in NL9980 and L9981 cell lines by MTT, plate, Boyden chamber methods and animal models.

RESULTS

(1)Two sub-cell lines, NL9980 and L9981 which had different metastatic phenotype, were successfully isolated and established from a human lung large cell carcinoma cell line (WCQH-9801). (2)The L9981 cell line had LOH of nm23-H1 gene, deletion of mRNA and protein expression of nm23-H1, but the NL9980 cell line had neither LOH of nm23-H1 nor deletion of mRNA and protein expression of nm23-H1. (3)The proliferation, clone formation and vitro invastion of L9981 cell line were significantly higher than those of NL9980 cell line. (4)The tumorigenicity and lung metastatic rate in nude mouse of L9981 cell line were remarkably higher than those of NL9980. (5) No significant difference of the chromosome number was observed between NL9980 and L9981 cell lines.

CONCLUSIONS

(1)NL9980 and L9981 cell lines established from a human lung large cell carcinoma cell line have different biological and molecular characteristics. (2)The high invsaion and metastasis ability of L9981 cell line might be related to the LOH of nm23-H1 gene.

[Study on the association between genetic polymorphism of CYP2E1, GSTM1 and susceptibility of lung cancer]

BACKGROUND

Lung cancer is the leading cause of malignant tumor death among Chinese population. It has been known that the development of lung cancer may be associated with genetic po-lymorphism of some lung cancer related genes. The aim of this study is to evaluate the relationship between genetic polymorphism of metabolizing enzymes and susceptibility of lung cancer in Chinese population.

METHODS

Polymorphism of CYP2E1 RsaI/PstI and GSTM1 was detected in 99 patients with lung cancer and 66 patients with benign pulmonary disease by PCR-RFLP and PCR. The association between genetic polymorphism and susceptibility of lung cancer was analyzed.

RESULTS

No significant difference in three RsaI/PstI genotype distribution of CYP2E1 was found between lung cancer group and control group (Chi-Square=1.374, P=0.241). (2) The frequency of GSTM1-null genotype in lung cancer group was significantly higher than that in control group (57.6% vs 40.9%, Chi-Square=4.401, P=0.036). (3) The individuals who carried with GSTM1-null genotype had a 1.96 fold increased risk of lung cancer (OR=1.96, 95%CI=1.042-3.689, P=0.037) than those who carried with GSTM1-present genotype. (4) When data were stratified by smoking status, the smokers who carried with c1/c1 genotype had a significantly higher risk of lung cancer (OR=3.525, 95%CI=1.168- 10.638, P=0.025) than those never-smokers who carried with at least one c2 allel. (5) When combination of polymorphism of CYP2E1 RsaI/PstI genotype and GSTM1 genotype was analyzed, compared with individuals who had concurrent present of GSTM1 and at least one c2 allel genotype, the risk of lung cancer for combination of GSTM1 null and c1/c1 genotype was increased significantly (OR=3.449, 95%CI=1.001- 11.886, P=0.050). Considering smoking status, compared with never-smokers who had concurrent present of GSTM1 and at least one c2 allel genotype, the risk of lung cancer for combination of GSTM1 null and c1/c1 genotype was remarkably increased (OR=11.553, 95%CI=1.068-124.944, P=0.044), as well as that for combination of GSTM1 null and at least one c2 allel genotype (OR=13.374, 95%CI=1.258-142.166, P= 0.032).

CONCLUSIONS

(1)GSTM1 null genotype is an important factor associated with increased risk of lung cancer. (2) The combination of c1/c1 and GSTM1-null genotype can remarkably increase risk of lung cancer both in smokers and non-smokers.

[Expression and Significance of bag-1, bcl-2 in Non-small Cell Lung Cancer and the Correlation with Multi-drug Resistance.]

BACKGROUND

bag-1, bcl-2 and bax are all apoptosis-related proteins. They play a role in the diagnosis, progress, metastasis and prognosis of tumor. The aim of the study was to investigate the expression of bag-1, bcl-2 and bax in non-small cell lung cancer, and to study the relationship between their expression levels and the clinical pathological characteristics, furthermore, to evaluate their correlation with multi-drug resistance.

METHODS

The expressions of bag-1, bcl-2 and bax in 140 non-small cell lung cancer tissues (40 of 140 were processed neoadjuvant chemotherapy) and 15 lung benign lesion tissues were examined with SP immuno-histochemical stain.

RESULTS

The positive expression rates of bag-1 and bcl-2 protein in non-small cell lung cancer were significantly higher than those in pulmonary benign lesion tissues (P<0.05), but the positive expression rate of bax in non-small cell lung cancer was significantly lower than that in pulmonary benign lesion tissues (P<0.05). The expressions of bag-1, bcl-2 and bax protein were not related to the age and sex of patients, histological classification, P-TNM stage and lymph node involvement of the cancer (P>0.05), but bag-1 was related to the differentiation degree of the tumor. The lower the differentiation was, the higher the levels of expression of bag-1 were. bcl-2 protein expression was highly positive correlated with the bag-1 protein expression in non-small cell lung cancer (r =0.371, P<0.01), and bcl-2 protein was highly negative correlated with bax protein expression (r=-0.225, P<0.01). The positive expression rates of bag-1 and bcl-2 showed increasing trends from the patients without neoadjuvant therapy to those with neoadjuvant therapy, but the difference had no statistic significance (P>0.05).

CONCLUSIONS

The high expression of bag-1, bcl-2 protein and the low expression of bax protein exist in nonsmall cell lung cancer. The expression level of bag-1 protein is closely related to the differentiation degree of non-small cell lung cancer. A highly positive correlation exists between bag-1 and bcl-2 expression, and a highly negative correlation is observed between bcl-2 and bax expression. The study doesn't provide the evidence that there is a close correlation between the expression levels of bag-1, bcl-2, bax and the multi-drug resistance in non-small cell lung cancer.

[Analysis of two-dimension gel electrophoresis of human large cell lung cancer cell lines with different metastasis potentials]

BACKGROUND

Metastasis is not only the malignant characteristics of lung can- cer, but also the chief cause of failure to cure and high mortality of lung cancer. To better explore and understand the mechanism of lung cancer metastasis and to search for potential markers for early diagnosing and reversing lung cancer metastasis, differential proteomic analysis is conducted in two human large cell lung cancer cell lines with high metastasis potentials (L9981) and low metastasis potentials (NL9980) by two-dimension gel electrophoresis (2-DE).

METHODS

The total proteins of the two cell lines were separated by immobilized pH gradient (IPG)-based 2-DE. The differentially expressed proteins of the two cell lines were analyzed using image analysis software.

RESULTS

A high resolution and reproducible 2-DE image was successfully obtained. Average deviations for protein position in IEF direction were (0.858±0.076)mm and (1.514±0.127)mm in SDS-PAGE direction. The relative standard deviation for protein volume was (12.06±0.580)% in L9981 and (12.22±0.640)% in NL9980. The average total number of protein spots was 902±169 in L9981 cells and 941±173 in NL9980 cells in three repeated experiments. Image analysis of siliver-stained 2-DE image revealed that 4 protein spots had significant differential expressions in L9981 and NL9980 (student's t-test, P < 0.05). Fifteen protein spots were only detected in L9981, and 27 protein spots were only detected in NL9980.

CONCLUSIONS

The results in this study suggest that an obviously differential proteomic expression exists between the human high- and low-metastatic large cell lung cancer cell lines. It will be helpful to further understand the molecular mechanisms of lung cancer invasion and metastasis, and provide new experimental evidence for searching metastatic-related molecule of lung cancer.

[Relationship between genetic polymorphism of GSTT1 gene and inherent susceptibility to lung cancer in Han population in Sichuan, China]

BACKGROUND

Some studies have supposed that glutathione S-transferases (GSTs) may be involved in detoxification of carcinogens, especially from tobacco smoke. Therefore, polymorphism of GSTs has been considered as potential protectors of individual cancer risk. The objective of this study is to investigate the relationship between genetic polymorphism of GSTT1 and inherent susceptibility to lung cancer in Han population in Sichuan, China.

METHODS

A case-control study was carried out to compare the distribution frequency of GSTT1 gene polymorphism between lung cancer (n=150) and control healthy individuals (n=152) with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method and to analyze the relationship between the GSTT1 gene polymorphism and smoking and the inherent susceptibility of lung cancer.

RESULTS

(1) The distribution frequency of GSTT1(-) genotype was 54.7% (82/150) in lung cancer and 38.2% (58/152) in control group respectively (OR=1.681, 95%CI=1.009- 2.803 , P=0.046); (2) GSTT1(-) genotype remarkably increased the risk of squamous cell carcinoma (OR=2.969, 95%CI= 1.511 -5.834, P=0.002) and adenocarcinoma (OR=2.095, 95%CI=1.060-4.140, P= 0.033 ); (3) In smokers, GSTT1(-) genotype significantly increased the risk for lung cancer (OR=4.051, 95%CI=1.959-8.380 , P=0.000); (4) In people with GSTT1(-) genotype, smoking markedly increased the risk for lung cancer (OR=53.885, 95%CI=11.789-246.302, P=0.000); (5) In heavy smokers (≥20 packyears), GSTT1(-) genotype could remarkably increase the risk of lung cancer (OR=4.296, 95%CI=1.649-11.190, P=0.003).

CONCLUSIONS

(1) People with GSTT1(-) genotype have significantly increased risk for lung cancer in Han population in Sichuan, China, especially for squamous cell carcinoma. (2) GSTT1(-) genotype interacts synergistically with smoking on lung cancer risk. The more the cigarettes smoke, the higher the risk of lung cancer increases in those people who are smokers with GSTT1(-) genotype.

[Transfection of tumor metastasis suppressor gene nm23-H1 can up-regulate the activity of GSK-3β in human high-metastasis large cell lung cancer cell line L9981]

BACKGROUND

To investigate the influence of tumor metastasis suppressor gene nm23-H1 on the activity of glycogen synthase kinase 3β (GSK-3β) in human high-metastasis large cell lung cancer cell line L9981.

METHODS

The levels of GSK-3β expression in cytoplasm and nucleus were determined with anti- GSK-3β antibody in human high-metastasis large cell lung cancer cell line L9981 (cell line with nm23-H1 gene deletion), L9981-nm23-H1 (cell line with nm23-H1 transfected) and L9981-pLXSN (cell line with vector transfected) by Western blot method. The activity of GSK-3β among those three cell lines was detected by immunoprecipitation and analysed by a radioactive isotope scintillation counter before and after treating with 20 mmol/L LiCl.

RESULTS

(1) The expression indensity of GSK-3β of cytoplasm and nucleus was (6 341±541) and (4 356±490) IOD in L9981-nm23-H1, (3 613±383) and (705±75) IOD in L9981-pLXSN, and (3 736±298) and (675±57) IOD in L9981, respectively. A high significance in GSK-3β expressive indensity of both cytoplasm and nucleus existed among L9981-nm23-H1, L9981-pLXSN and L9981 (P < 0.01); Multiple comparison: A highly significant difference was observed when L9981-nm23-H1 was compared with L9981-pLXSN or L9981 (P < 0.01), but no significant difference was observed between L9981-pLXSN and L9981 (P > 0.05). (2) The GSK-3β activity of cytoplasm and nucleus was (28 955±2 509) and (9 247±924) CPM in L9981-nm23-H1, (11 241±1 495) and (1 492±176) CPM in L9981-pLXSN, and (12 505±1 469) and (1 763±125) CPM in L9981, respectively. A highly significant difference in GSK-3β activity of both cytoplasm and nucleus existed among L9981-nm23-H1, L9981-pLXSN and L9981 (P < 0.01); Multiple comparison: the GSK-3β activity in L9981-nm23-H1 was significantly higher than that in L9981-pLXSN and L9981 (P < 0.01), but no significant difference was observed between the L9981-pLXSN and L9981 (P > 0.05). (3) After treatment with 20 mmol/L LiCl, the expressive indensity of GSK-3β of cytoplasm and nucleus was (4 718±549) and (3 823±350) IOD in L9981-nm23-H1, (2 030±155) and (217±15) IOD in L9981-pLXSN, and (2 164±151) and (224±19) IOD in L9981, respectively. No significant difference in GSK-3β expressive indensity existed between before and after treatment with LiCl in L9981-nm23-H1 (P > 0.05). However, the GSK-3β expressive indensity in cytoplasm and nucleus before treatment was remarkably higher than those after treatment in both L9981-pLXSN and L9981 (P < 0.05). (4) After treatment with 20 mmol/L LiCl, the GSK-3β activity in cytoplasm and nucleus was (11 099±1 112) and (3 748±215) CPM in L9981-nm23-H1, (4 447±430) and (1067±159) CPM in L9981, and (4 435±427) and (909±156) CPM in L9981-pLXSN, respectively. The GSK-3β activity both in cytoplasm and nucleus after treatment with LiCl was remarkably lower than that before treatment in L9981-nm23-H1, L9981-pLXSN and L9981 (P < 0.01 or P < 0.05).

CONCLUSIONS

(1) Transfection of nm23-H1 gene can significantly up-regulate the expression level and activity of GSK-3β in human high-metastasis large cell lung cancer cell line L9981; (2) LiCl can remarkably suppress the upregulation effects of nm23-H1 gene on GSK-3β activity in L9981 cell line; (3) The effects of nm23-H1 gene on suppressing the signal transduction of Wnt pathway might be carried out through upregulating GSK-3β expression and activity in human high-metastasis large cell lung cancer cell line L9981.

[Establishment of a human large cell lung cancer cell line L9981-nm23-H1]

BACKGROUND

To establish a human large cell lung cancer cell line L9981-nm23-H1 transfected with wild type nm23-H1 gene.

METHODS

pLXSN-nm23-H1-EGFP was constructed by gene clone technique, and L9981-nm23-H1 was established by infected virus of nm23-H1 gene. The DNA and protein expression of nm23-H1 were detected in the transgene large cell lung cancer cell line by PCR and Western blot.

RESULTS

pLXSN-nm23-H1-EGFP was constructed successfully, and the nm23-H1 cDNA was inducted to L9981 cell. The protein of nm23-H1 could be detected in L9981-nm23-H1 cell.

CONCLUSIONS

Protein of nm23-H1 is stably, continuously and high efficiently expressed in L9981-nm23-H1 cell.

[Effect of 20(R) ginsenoside Rg3 on protein expression of lung cancer cell line.]

BACKGROUND

Lung cancer is the most dangerous threating tumor to human's health and life. Metastasis is not only the malignant characteristics of lung cancer, but also the chief cause of failure to cure the disease and of high mortality. Ginsenoside Rg3 has been proved to have obvious effect against tumor. The molecular mechanism of Rg3 against lung cancer cell line will be investigated by using two-dimensional gel electrophoresis in this paper.

METHODS

The IC50 of Rg3 against human high-metastatic large cell lung cancer cell line 95D was determined by MTT. Then 95D cells were treated with Rg3 at the concentration of 0.1*IC50 for 72 h. The total proteins of 95D cell line treated with Rg3 and not treated were separated and protein profiles were obtained by using immobilized PH gradient (IPG)-based two-dimensional gel electrophoresis. The differential expression proteins of 95D cell line treated with Rg3 and not treated were analyzed using image analysis software.15 of differentially expressed proteins were further identified using MALDI-TOF MS/MS analysis and LC-MS/MS analysis. Protein identification was performed by searching the protein database.

RESULTS

The IC50 of Rg3 against 95D cell line was 100 mug/mL. There were 27 differently expressed protein spots through analysis by Image Master Microsoft.15 proteins were identified using mass spectrometry. Chloride intracellular channel protein 1, Ubiquitin-Conjugating Enzyme E2-25 Kda only expressed in control; 14-3-3 protein teta, SKI-interacting protein only expressed in 95D cell line treated by Rg3; Annexin A2, profilin 2 isoform b were downregulated in 95D cell line treated by Rg3; 14-3-3 protein zeta, Eukaryotic translation initiation factor 4H were upregulated in 95D cell line treated by Rg3.

CONCLUSIONS

A significantly different expression of proteins were found in 95D cell line treated with Rg3 and those not treated. Most of identified proteins have been reported to be associated with tumor metastasis. The identified proteins will provide the basis for searching potential biomarkers and the molecular mechanism of Rg3 against the metastasis of lung cancer cells.

A novel method to select informative SNPs and their application in genetic association studies

The association studies between complex diseases and single nucleotide polymorphisms (SNPs) or haplotypes have recently received great attention. However, these studies are limited by the cost of genotyping all SNPs. Therefore, it is essential to find a small subset of tag SNPs representing the rest of the SNPs. The presence of linkage disequilibrium between tag SNPs and the disease variant (genotyped or not), may allow fine mapping study. In this paper, we combine a nearest-means classifier (NMC) and ant colony algorithm to select tags. Results show that our method (ACO/NMC) can get a similar prediction accuracy with method BPSO/SVM and is better than BPSO/STAMPA for small data sets. For large data sets, although the prediction accuracy of our method is lower than BPSO/SVM, ACO/NMC can reach a high accuracy (>99 percent) in a relatively short time. when the number of tags increases, the time complexity of NMC is nearly linear growth. To find out that the ability of tags to locate disease locus, we simulate a case-control study and use two-locus haplotype analysis to quantitatively assess the power. The result showed that 20 percent of all SNPs selected by NMC have about 10 percent higher power than random tags, on average.