Human High-metastatic Large Cell Lung Research Articles

Screening and establishment of human lung cancer cell lines with organ-specific metastasis potential

背景与目的肺癌转移是肺癌的恶性标志和特征，也是肺癌病人治疗失败和死亡的主要原因。肺癌转移具有器官特异性，最常转移的部位是淋巴结、大脑、骨、肝脏和肾上腺。本研究的目的是应用我们实验室的人高转移大细胞肺癌细胞株L9981，筛选鉴定出具有器官特异性转移的肺癌亚代细胞株，为进一步研究肺癌细胞器官特异转移提供科学可靠的细胞模型。方法通过裸鼠实验，将母系细胞株L9981-Luc皮下接种，每周一次动物活体成像观察肺癌器官转移情况，数周后构建出具有肺、脊柱、纵隔淋巴结和大脑等器官特异性转移的小鼠模型；处死裸鼠，切取肺、脊柱、纵隔淋巴结和大脑器官肺癌转移瘤进行原代培养，构建具有器官靶向特异性转移潜能的肺癌亚代细胞株；将第一代器官特异性转移肺癌细胞株接种裸鼠皮下，再次构建肺癌器官特异性转移小鼠模型；通过反复多次将肺癌器官特异性转移瘤构建肺癌细胞株，再裸鼠接种，最终获得具有肺、脊柱、纵隔淋巴结和大脑器官特异性转移的肺癌细胞株。结果经过裸鼠反复接种，动物活体成像、动物体内反复筛选鉴定，成功构建了4株分别特异性转移到肺、脊柱、纵隔淋巴结和大脑的器官特异性转移肺癌细胞株，分别命名为L9981-LuM、L9981- BoM、L9981-LnM和L9981-BrM。结论成功构建出具有肺、纵隔淋巴结、脊柱和大脑特异性转移的人大细胞肺癌细 胞模型，为进一步研究肺癌器官特异转移的分子机制、信号调控途径，以及未来研究和开发抑制或/和阻断肺癌转移的分子靶向药物提供了可靠的细胞模型。

A proteomic approach to elucidate the multiple targets of selenium-induced cell-growth inhibition in human lung cancer.

Methylseleninic acid (MSA) has been implicated as a promising anticancer agent for lung cancer. However, the underlying molecular mechanism(s) responsible for MSA's action is not well understood. Our study aimed to examine the cellular effects of MSA on L9981 human high-metastatic large cell lung cancer cells and gain insights into its possible molecular mechanism(s) through a proteomic approach. L9981 cells were exposed to MSA at different concentrations and time points. The effects of MSA on cell proliferation and apoptosis were detected by cell viability analyzer Vi-CELL and flow cytometric analysis, respectively. We analyzed the alterations in the proteome profile of L9981 cells induced by MSA using the 2-D difference in gel electrophoresis (2-D DIGE) and identified the differentially expressed proteins using a liquid chromatography system followed by tandem mass spectrometry (LC-MS/MS). We found that MSA inhibited cell proliferation in a dose-dependent manner and significantly induced early apoptosis in L9981 cells. 2-D DIGE showed that MSA induced significant changes (>1.29 fold) in the expression levels of 42 protein spots compared to the untreated control (P < 0.05). As identified by LC-MS/MS, proteins that underwent changes in response to MSA were related to various biological functions, including: (i) endoplasmic reticulum stress (upregulation of molecular chaperones like heat shock protein A5, protein disulfide-isomerase precursor, and calreticulin precursor); (ii) oxidative stress response/ thioredoxin system (decreased thioredoxin-like protein 1 and increased thioredoxin reductase 1); (iii) translation regulation (downregulation of translation factors like elongation factor 1-beta and eukaryotic translation initiation factor 6); (iv) mitochondrial bioenergetic function (upregulation of adenosine triphosphate synthase subunit beta and mitochondria); and (v) cell signal transduction regulation (decreased peptidyl-prolyl cis-trans isomerase A and 14-3-3 protein gamma). The protein and gene expression levels of those proteins of interest were further confirmed by Western blot and/or real-time reverse transcription polymerase chain reaction. Our results suggest that MSA may inhibit cell proliferation and induce apoptosis in lung cancer by modulating multiple targets involved in various crucial cellular processes.

Methylation profile difference in human high-metastatic large cell lung cancer cell line L9981 and low-metastatic large cell lung cancer line NL9980

背景与目的肺癌是人类肿瘤中最容易发生侵袭转移的恶性肿瘤之一。影响肺癌患者预后及生存的最主要因素是远处转移。本文旨在分析具有相似遗传背景和不同转移潜能的人大细胞肺癌细胞株间基因甲基化的差异，为深入研究肿瘤转移机制提供充分的目标基因选择和发现肿瘤相关的新基因的机会。方法应用全基因组甲基化芯片杂交技术分析具有相同遗传背景和不同转移潜能的人大细胞肺癌细胞株L9981和NL9980之间差异甲基化基因，并运用生物信息学的方法分析这些差异基因。结果与NL9980相比，在L9981细胞株中有1 552个高甲基化DNA片断共涉及735个基因，其中656个已知基因及79个未知基因。低甲基化DNA片段1 787个，涉及809个基因，其中698个已知基因及111个未知基因。这些基因涉及细胞生物进程及其调节、基因表达、信号传导、细胞通讯、细胞运动、细胞粘附及血管生成等。结论抑癌基因及信号通路负向调节基因的高甲基化及癌基因、细胞粘附因子的低甲基化可能与L9981的侵袭性及克隆能力强有关。

The mechanism and influence on the biological behavior of human high-metastatic large cell lung cancer cell lines with transfection of nm23-H1 gene.

It has been confirmed that nm23-H1 gene is one of the tumor metastasis suppressor genes. Up to now, the exact mechanism of nm23-H1 gene is uncertian. The aim of this study is to compare the biological behavior changes among three human high-metastatic large cell lung cancer cell lines which transfected and untransfected nm23-H1 gene, and to study the mechanism of nm23-H1 gene supressing the metastasis. Boyden Chamber and MTT method were used to detect the rates of invasion and proliferation among different human pulmonary carcinoma cells of transfected and untransfected nm23-H1 gene; meanwhile The three lung cancer cell lines were treated with PKC inhibitor Calphostin C, and the above measurements were also performed. The ability of invasion and proliferation of L9981 and L9981-PLXSN human high-metastatic large cell lung cancer cells,which lack of nm23-H1gene, was higher than that of L9981-nm23-H1 human high-metastatic large cell line, which transfected with nm23-H1gene (P <0.001). There was no difference beteween L9981 and L9981-PLXSN cell lines (P >0.05). After treated with PKC inhibitor Calphstin C,the invasion and proliferation ability of three lung cancer cell lines were obviously go down (P <0.001), however, the invasion and proliferation ability of L9981-nm23-H1 lung cancer cell line was still lower than those of L9981 and L9981-PLXSN lung cancer cell lines (P <0.001), and there was also no significant difference between two later cell lines (P >0.05). Our data suggest that nm23-H1 gene can significantly inhibit the cell proliferation and invasion in L9981 lung cancer line. The effect of nm23-H1 might be correlated with downregulation of PKC signal transduction in human high-metastatic large cell lung cancer cell line.

Selenium compounds induce ROS in human high-metastatic large cell lung cancer cell line L9981.

It has been proved that methylseleninic acid (MSA) is a kind of artificially developed selenium compound, which appeared to be the best candidate for cancer prevention and therapy. Reduced glutathione is not only critical to MSA metabolism, but also is a kind of protective antioxidant which could remove the oxygen free radical promptly and maintain the intracellular redox status stable. The aim of this study is to explore the anticancer effects of ROS induced by MSA and the molecular mechanisms of MSA on induction of ROS. We confirmed that MSA and selenite have the anticancer effect in the human high-metastatic large cell lung cancer cell line L9981 by growth inhibition detection, we detect the ROS induced by MSA and selenite in L9981 by fluorescence microscopy, and use flow cytometry to quantitate the ROS induced by NAC together with selenium compounds. (1)MSA 2.5 muM and 5.0 muM selenite could inhibit the L9981 growth, Increasing the concentration resulted in a more pronounced effect. (2)MSA and selenite could induce ROS in L9981. (3)incubated NAC with selenite could significantly inhibit the ROS but increase the ROS treated by NAC with MSA. (1)MSA and selenite had anti-L9981 effect. (2)Oxidative stress reaction may participate in the induction of apoptosis by MSA and selenite in lung cancer cell line L9981.

The variation of intracellular distribution and translocation of the protein kinase C alpha among human lung cancer cell line with different metastasis potential.

Protein Kinase C (PKC) is one of the key kinases in the cell signal transduction passway. There are more reports about it's ability on cell proliferation, but fewer on invasion and metastasis in the past; and it's mechanisms are unclear. The aim of this study is to analyze the variation of intracellular distribution and translocation of the protein kinase C alpha among human high-metastatic large cell lung cancer cell line with different metastasis potential,in order to investigate the correlation between the lung carcinoma invasion and metastasis and the PKC isoforms. Using Western blot and laser scanning confocal microscope (LSCM) method. The distribution of PKC alpha in cytosol and plasma membrane and translocation were detected among different metastatic potential human pulmonary carcinoma cells L9981, L9981-pLXSN and L9981-nm23-H1 before and after treatment with PKC inhibitor Calphostin C, by Western blot and LSCM. PKC alpha in L9981 and L9981- pLXSN was mainly expressed on membrane, which was remarkably higher than those in L9981-nm23-H1 cell line (P =0.001); while expression of PKC alpha in cytoslol in L9981 and L9981-pLXSN cell lines, was lower than those in L9981-nm23-H1 cell line (P <0.001). The expression of PKC alpha in cytosol in L9981-nm23-H1 cell line was remarkably higher than those in L9981 and L9981-pLXSN cell lines (P <0.001), while expression of PKC alpha in plasma membrane in L9981-nm23-H1 cell line, was significantly lower than those in L9981 and L9981- pLXSN cell lines (P =0.001). PKC alpha is mainly located in nucleus and perinucleus in L9981 and L9981-pLXSN cells, which was in active status, In L9981-nm23-H1 cell line, PKC alpha is mainly located in soluble cytosolic section, which was in inactive status. After treated with PKC inhibitor Calphostin C, the expression of PKC alpha in membrane in L9981, L9981-pLXSN and L9981-nm23-H1 was downregulated, and PKC alpha were observed mainly located in cytosolic site in all the three cell lines, which was mainly in inactive status. The study suggests that PKC isoforms is closely correlated with human lung cancer invasion and metastasis.

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

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. 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. 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. 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.

P2-034: The molecular mechanism of Nm23-H1 gene transfection on reversing invasion and metastasis phenotype in human high-metastatic large cell lung cancer cell line L9981

P2-034: The molecular mechanism of Nm23-H1 gene transfection on reversing invasion and metastasis phenotype in human high-metastatic large cell lung cancer cell line L9981

Experimental study on molecular mechanism of nm23-H1 gene transfection reversing the malignant phenotype of human high-metastatic large cell lung cancer cell line

nm23-H1 gene is a well-known tumor metastasis suppression gene. Our previous study has found that transfection of wild type nm23-H1 gene can significantly downregulate the ERK1/2 activity of human high-metastatic large cell lung cancer cell line L9981. The aim of this study is to investigate the influence of nm23-H1 and exogenous ERK1/2 pathway inhibitor U0126 on the extracellular signal-regulated kinase (ERK1/2) of human high-metastatic large cell lung cancer cell line L9981 and its malignant biological behaviors. The expressive levels of total-ERK1/2, dually phosphorylated ERK1/2 and ERK1/2 relative activity of the human high-metastatic large cell lung cancer cell lines, L9981 (parent cell line with nm23-H1 gene hetero-deletion), L9981-nm23-H1 (transfected with nm23-H1 gene ) and L9981-PLXSN (transfected with vector) were detected by Western blot and immunoprecipitation technique after treating with U0126 (40μmol/L for 20 minutes). The in vitro proliferative and invasive abilities among the above three lung cancer cell lines were determined by MTT and improved Boyden chamber methods. The phosphorylated ERK1/2 expression level and relative activity in L9981-nm23-H1 lung cancer cell line were remarkably lower than those in L9981 and L9981-PLXSN lung cancer cell lines after being treated with U0126 (P < 0.01), but there was no significant difference between L9981 and L9981-PLXSN lung cancer cell lines. No significant difference of total ERK1/2 expression level was observed among the three lung cancer cell lines (P > 0.05) after being treated with U0126. The in vitro proliferation and invasion of L9981-nm-23H1 lung cancer cell line were remarkably lower than those of L9981 and L9981-PLXSN lung cancer cell lines (P < 0.01 ), but no significant difference was found between L9981 and L9981-PLXSN lung cancer cell lines (P > 0.05 ); U0126 could significantly down-regulate the in vitro proliferation and invasion of L9981 lung cancer cell line (P < 0.01). Blocking the activity of ERK1/2 in L9981 lung cancer cell line and transfecting the nm23-H1 gene into the L9981 lung cancer cell line may produce similar cell biological behavior changes, namely the significant reduction of in vitro proliferation and invasion of L9981 lung cancer cell line. These results indicate that the molecular mechanism which nm23-H1 gene reverses invasion and proliferation of the human high-metastatic large cell lung cancer cell line may be related to its effects of down-regulating the activity of the key kinase ERK1/2 of Ras-to-MAPK signal transduction pathway.

Primary experimental results of methylseleninic acid on the proliferation inhibition and apoptotic induction in human high-metastatic large cell lung cancer cell line L9981

It has been proved that selenium has remarkable effects in the prevention of cancer and proliferation inhibition for breast cancer and prostate cancer. Up to now, little is known, however, if methylseleninic acid (MSA) has the anticancer effect on lung cancer or not. The objective of this study is to detect the effect of MSA on proliferation inhibition and apoptotic induction for human high-metastatic large cell lung cancer cell line L9981, and to explore the molecular mechanisms. The changes of proliferation, clone formation, apoptotic level and cell cycles were detected in L9981 by trypan blue staining, clone formation suppression test, and flow cytometry before and after treating with different concentration of MSA. The expression level of proliferative-related and apoptotic-related genes was also determined in L9981 by flow cytometry. (1)The proliferation ability of L9981 was remarkably inhibited at the concentration of 0.5μmol/L of MSA (P < 0.05), and the cells were arrested at G0/G1 phase after treating with the same concentration. (2)Apoptosis of L9981 was remarkably induced by MSA at the concentration of 2.5μmol/L (P < 0.05). (3)The clone formation ability of L9981 was significantly suppressed by MSA at the concentration of 5.0μmol/L (P < 0.05). (4)The expression levels of P53, P21, Fas, FasL and Bax were remarkably up-regulated after treatment with MSA. (1)MSA can significantly suppress the proliferation and clone formation ability of human high-metastatic large cell lung cancer cell line L9981, and also induce apoptosis of L9981. (2)The anticancer effects of MSA might be related to regulate the expression of cell cycle-related genes and apoptotic-related genes in the human high-metastatic large cell lung cancer line L9981.

Effects of polysaccharid on expression of angiogenic-related genes in human high-metastatic large cell lung cancer cell line L9981

Lung cancer is one of the most malignant cancers which is hazarding the people's health and life in the world. At present, it is a highlight to exploit antitumor drug from plant at home and abroad. The aim of this study is to observe the effects of polysaccharid (PS-T) on expression of angiogenic-related gene mRNA in human high-metastatic large cell lung cancer cell line L9981, and to explore its possible molecular mechanism. L9981 in vitro was cultured, and the growth data were obtained by trypan blue staining. The mRNA transcript expression of β-catenin, E-cadherin, TIMP-1, CD44V6, MMP-2, endostatin, VEGF was detected in L9981 by RT-PCR before and after treating with PS-T. The ability of invasion of L9981 was determined by Boyden chamber method. (1)PS-T had remarkably inhibitive effects on the growth of L9981 in vitro. The inhibitive rate of PS-T on L9981 was concentration-dependent. No significant difference of inhibitive rate was found among the PS-T (1g/L), cisplatin (3mg/L) and PS-T (0.05g/L) + cisplatin (1.5mg/L)(P > 0.05). (2)The mRNA expression level of β-catenin, E-cadherin, TIMP-1, endostatin and MMP-2 was upregulated, while that of VEGF and CD44V6 was downregulated. Out of them the mRNA expression level of TIMP-1 and endostatin was remarkably upregulated, the expression level of CD44V6 was significanyly downregulated. (3)The in vitro invasive abilities of L9981 was significantly decreased in the PS-T, DDP and PS-T+DDP groups compared with that in blank control group. (1)PT-S could inhibit the growth of human high-metastatic large cell lung cancer cell line L9981 in vitro, the effect is dose-dependent. (2)PS-T can down- or up-regulate the mRNA transcript expression of some angiogenic-related gene mRNA. (3)PS-T has remarkably coordinating effects with cisplatin in the L9981 lung cancer cell line.

Effects of nm23-H1 point mutation on activity of GSK-3β in human high-metastatic large cell lung cancer cell line L9981

The results of our previous studies have proven that nm23-H1 gene can suppress metastasis of lung cancer, which may be associated with suppression of the Wnt signal pathway through up-regulating the activity of glycogen synthase kinase 3β (GSK-3β), the key kinase of the Wnt signal pathway. The aim of this study is to investigate the effect of point mutation of nm23-H1 gene on GSK-3β activity in cytoplasm and nucleus in human high-metastatic large cell lung cancer cell line L9981. Using immunoprecipitation and a radioactive isotope scintillation counter, the activity of GSK-3β was detected in cytoplasm and nucleus of human low-metastatic large cell lung cancer cell line NL9980, human high-metastatic large cell lung cancer cell line L9981, L9981-pEGFP (transfected with vector), L9981-nm23-H1-pEGFP (transfected with wild type nm23-H1), L9981-nm23-H1 S44A -pEGFP mutant (transfected with serine 44 to alanineon of nm23-H1 gene), L9981-nm23-H1 P96S -pEGFP mutant (transfected with proline 96 to serine of nm23-H1 gene), L9981-nm23-H1 H118F -pEGFP mutant (transfected with histidine 118 to phenylalanine of nm23-H1 gene) and L9981-nm23-H1 S120G -pEGFP mutant (transfected with serine 120 to glycine of nm23-H1 gene). The GSK-3β activity in cytoplasm and nucleus was remarkably decreased in the transgene lung cancer cell lines transfected with mutant nm23-H1 cDNA (L9981-nm23-H1 S44A -pEGFP, L9981-nm23-H1 P96S -pEGFP, L9981-nm23-H1 H118F -pEGFP and L9981-nm23-H1 S120G -pEGFP). Significant differences of GSK-3β activity in cytoplasm and nucleus were observed (P < 0.05) when L9981-nm23-H1-pEGFP cell line was compared with L9981-nm23-H1 S44A -pEGFP, L9981-nm23-H1 P96S -pEGFP, L9981-nm23-H1 H118F -pEGFP and L9981-nm23-H1 S120G -pEGFP lung cancer cell lines. There was a highly significant difference in GSK-3β activity in the cytoplasm between L9981-nm23-H1-pEGFP cell line and L9981-nm23-H1 P96S -pEGFP lung cancer cell line (P < 0.01 ). A highly significant difference in GSK-3β activity in the nucleus was observed (P < 0.01) when L9981-nm23-H1-pEGFP lung cancer cell line was compared with L9981-nm23-H1 S44A -pEGFP, L9981-nm23-H1 P96S -pEGFP and L9981-nm23-H1 H118F -pEGFP lung cancer cell lines. (1) Point mutation of nm23-H1 gene can significantly influence the regulating effects on the GSK-3β activity in the cytoplasm and nucleus in the human high-metastatic large cell lung cancer cell line L9981. (2) The effects of nm23-H1 gene on metastatic phenotype may be related to the upregulation of GSK-3β activity in human high-metastatic large cell lung cancer cell line L9981.

Effects of targeting inhibition of ERK1/2 signal transduction pathway on malignant biological behaviors of human high-metastatic large cell lung cancer cell line L9981

It has been known that oncogenesis and development of lung can- cer is a complex process regulated many genes and involved in multistages. Recent studies have demonstrated that signal transduction abnormality may play a very important role in these procedures. The aim of this study is to investigate the influence of exogenous MEK1/2 pathway inhibitor U0126 on the expression and activity of extracellular signal-regulated kinase (ERK1/2) of human high-metastatic large cell lung cancer cell line L9981 and its malignant biological behaviors. The expressive levels of total-ERK1/2, dually phosphorylated ERK1/2 and ERK1/2 relative activity of the human high-metastatic large cell lung cancer cell line L9981 (parent cell line with nm23-H1 gene hetero-deletion ) were detected by Western blot and immuno-precipitation technique after treating with different doses of U0126. The in vitro proliferative and invasive abilities of the lung cancer cell line were determined by MTT and modified Boyden chamber methods. The ERK1/2 relative activity of L9981 gradually decreased accompanied with increase of U0126 doses, and a highly significant difference of phosphorylated ERK1/2 expression level existed among the different concentration groups of U0126 (P < 0.01), but no significant difference of total ERK1/2 expression was found among the different concentration groups of U0126 (P=0.387). After treatment with same concentration of U0126 for different time, the ERK1/2 relative activity of L9981 gradually decreased as the treatment time of U0126 prolonging, and a highly significant difference of phosphorylated ERK1/2 expression level was observed among different treatment time groups (P < 0.01). But no significant difference of total ERK1/2 expression level was found among different time groups (P=0.689). The inhibition of ERK1/2 pathway by MEK1/2 specific inhibitor U0126 targeting the ERK1/2 pathway of L9981 was dose- and time-dependent. After treatment with different concentration of U0126, the proliferation of L9981 gradually decreased accompanied with increase of U0126 concentration and a highly significant difference existed among different groups of U0126 concentration (P < 0.001). The in vitro invasion of L9981 gradually decreased accompanied with increase of U0126 concentration. No significant difference of in vitro invasion of L9981 was found among 0, 10 and 20μmol/l of U0126 (P > 0.05). A highly significant difference was observed when U0126 concentration increased to 40 and 60μmol/l compared with 0, 10 and 20μmol/l of U0126 (P < 0.001). The inhibition of Ras-to-MAPK pathway by Ras-to-MAPK specific inhibitor U0126 targeting the Ras-to-MAPK pathway of the human high-metastatic large cell lung cancer cell line L9981 is dose-dependent and time-dependent. Suppressing or blocking of Ras-to-MAPK signal transduction pathway can reverse the invasive and metastatic phenotype of the human high-metastatic large cell lung cancer cell line L9981. These results suggest that the key kinase MEK1/2 of the ERK1/2 pathway may be a potent therapeutic target for human lung cancer.

Effects of transfection of nm23-H1 gene on β-catenin expression in human high-metastatic large cell lung cancer cell line L9981

To explore the effects of transfection of nm23-H1 gene on expression of β-catenin and phospho-β-catenin in human high-metastatic large cell lung cancer line L9981, and to provide evidence to elucidate the molecular mechanism of nm23-H1 mediated tumor metastatic suppression. To determine whether nm23-H1 contributes to cytoplasm and nuclear β-catenin and phospho-β-catenin expression, the expression level of β-catenin and phospho-β-catenin in cytoplasm and nucleus was detected in human high-metastatic large cell lung carcinoma cell lines including primary cell line L9981 with nm23-H1 gene deletion, L9981-nm23-H1 transfected with nm23-H1 gene, and L9981-pLXSN transfected with vector by Western blot. (1)β-catenin expression in L9981-nm23-H1 cytoplasm (IOD) (3 649±118) was significantly higher than that in L9981 (1 401±31) and L9981-pLXSN (1 350±55) cell lines (P < 0.001);(2)There was no statistical diffe-rence of the β-catenin expression in nucleus among L9981-nm23-H1 (2 945±68), L9981 (2 604±23) and L9981-pLXSN (2 652±53) cell lines (P > 0.05);(3)Phospho-β-cetenin expression of cytoplasm in L9981-nm23-H1 cell line (3 123±102) was significantly lower than that in L9981 (4 362±131) and L9981-pLXSN ( 4 500 ±117) cell lines (P < 0.001);(4)Phospho-β-catenin expression of nucleus in L9981-nm23-H1 (5 136±112) was significantly higher than that in L9981 (2 666±116) and L9981-pLXSN (2 661±66) cell lines (P < 0.001);(5)There was no statistical difference of β-catenin or phospho-β-catenin expression in cytoplasm and nucleus between L9981 and L9981-pLXSN cell lines (P > 0.05). (1)nm23-H1 gene transfection can remarkably upregulates the expression of cytoplasm β-catenin in human high-metastatic large cell lung cancer cell line L9981, but do not induce the nucleus accumulation of β-catenin; (2)Transfection of nm23-H1 gene can significantly upregulate the expression of phospho-β-catenin in nucleus and remarkably downregulate the expression of phospho-β-catenin in cytoplasm of L9981; (3)Regulation of the expression of the key modecule, β-catenin, in Wnt signal pathway might be the important melecular mechanisms which nm23-H1 gene controls "Lung Cancer Metastatic Suppresive Cascade" and reverves cancer metastasis in L9981.

Targeting blockage of Wnt signal transduction pathway of nm23-H1 gene transfection in human high-metastatic large cell lung cancer cell line L9981

To explore the possibility of targeting blockage of Wnt signal transduction pathway of nm23-H1 gene transfection in human high-metastatic large cell lung cancer cell line L9981, and to provide evidence to elucidate the signal conductive mechanism of nm23-H1 mediated tumor metastasis suppression. The expression of GSK-3β and β-catenin of Wnt signal pathway was detected in cytoplasm and nucleus in L9981 cell line with nm23-H1 deletion, L9981-pLXSN cell line transfected with vector and L9981-nm23-H1 cell line transfected with nm23-H1 gene by Western blot. (1)GSK-3β expression in L9981-nm23-H1 cytoplasm (6 341±541) was significantly higher than those in L9981 (3 736±298) and L9981-pLXSN (3 613±383) cell lines ( P < 0.001); (2)GSK-3β expression in L9981-nm23-H1 nucleus (4 356±490) was significantly higher than those in L9981 (657±57) and L9981-pLXSN (705±75) cell lines ( P < 0.001); (3)β-catenin expression in L9981-nm23-H1 cytoplasm (3 649±118) was significantly higher than those in L9981 (1 401±31) and L9981-pLXSN (1 350±55) cell lines ( P < 0.001); (4)No statistical difference of the β-catenin expression in nucleus was observed among L9981-nm23-H1 (2 945±68), L9981 (2 604±23) and L9981-pLXSN (2 652±53)( P > 0.05); (5)No significant difference of GSK-3β or β-catenin expression in cytoplasm and nucleus was observed between L9981 and L9981-pLXSN ( P > 0.05). (1)nm23-H1 gene can remarkably upregulate the expression of GSK-3β in cytoplasm and nucleus, and β-catenin expression in cytoplasm in L9981-nm23-H1 cell, but can not induce the nucleus accumulation of β-catenin. (2)Regulation of GSK-3β and β-catenin expression, and targeting blockage of Wnt signaling pathway may be one of molecular mechanisms that nm23-H1 contributes to play a vital role in the "Lung Cancer Metastasis Suppressive Cascade".