Objective To explore the effect of Yes-associated protein 1 (YAP1) and potential mechanism on erlotinib ( ER) resistance in lung adenocarcinoma.Methods In PC-9 cells and acquired ER resistant PC-9 ( PC-9/ER) cells, the expression changes in YAP1 gene were measured by quantitative real-time PCR( RT-qPCR) and Western blot.Indirect immunofluorescence was adopted to observe the location of YAP1.PC-9/ER cells were treated with the verteporfin ( VP, YAP1 inhibitor) for 24 h and 48 h, respectively.Expression changes in mRNA and proteins of YAP1, AKT and p-AKT were detected in the presence or absence of VP.The effect of VP was analyzed by drug resistance index using Cell Counting Kit 8(CCK-8) assay.Results The resistance index of PC-9/ER cells was (99.80 ±25.81).Compared with PC-9 cells, the expression levels of YAP1 mRNA and protein were increased in PC-9/ER.The inhibitory efficiency of VP was (50.96 ±5.86)%, and the levels of AKT and p-AKT proteins were down-regulated by the inhibition of YAP1 simultaneously.The half maximal inhibitory concentration (IC50) of PC-9/ER decreased from (11.10 ±2.72) to (1.47 ± 0.32)μmol/L (P =0.024).Resistance index was reduced to one eighth of the original.Conclusion These results indicate that the YAP1 mediates ER resistance in lung adenocarcinoma.Suppression of YAP1 can reduce the resistance through PI3K/AKT signaling pathway.Therefore, YAP1 may be a potential target for lung cancer gene therapy.

Objective To investigate the value of detecting plasma microRNA‐125a‐3p(miRNA‐125a‐3p) ,IGF‐2 on monitoring invasion and metastasis in NSCLC ,and to study the correlation between miR‐125a‐3p and IGF‐2 .Methods miR‐125a‐3p transcripts of 20 controls ,73 NSCLC were performed in plasma by quantitative reverse transcription‐polymerase chain reaction(qRT‐PCR) and PCR data was analyzed by the 2‐ΔΔCT method .The expression of IGF‐2 in plasma was detected by ELISA .Results The expression of miR‐125a‐3p in stage Ⅲ /Ⅳ was lower than stage Ⅰ/Ⅱ and the controls(P=0 .001 ,P=0 .005) .There was no statistical differ‐ence between the stage Ⅰ /Ⅱ patients and the controls(P=0 .776) .The expression of miR‐125a‐3p was related with lymph node metastas ,lower expression in positive lymph node metastasis (P=0 .003) .The expression of IGF‐2 in stage Ⅰ /Ⅱ 、stage Ⅲ /Ⅳ was higher than the controls(P=0 .036 ,P=0 .011) .There was no statistical difference between the stageⅠ/Ⅱ and stage Ⅲ/Ⅳ (P=0 .451) . The expression of IGF‐2 was related with lymph node metastas ,higher expression in positive lymph node metastasis (P=0 .037) .The re‐sults showed a negative correlation between miR‐125a‐3p expression and IGF‐2 in plasma(r= -0 .280 ,P=0 .007) .Conclusion Low ex‐pression of miR‐125a‐3p and high expression of IGF‐2 in plasma may play a role in invasion and metastasis of NSCLC .miR‐125a‐3p may play a negative regulatory role on IGF‐2 .

Chemotherapy treatment plays an important role in the comprehensive treatment of malignant disease,but the chemotherapy related knowledge and the selection of an appropriate regimen for certain patient are hard to master.The establishment of computer-assisted cancer chemotherapy program and management system with a follow-up database of cancer patients can help the oncologist to master the designing skill of chemotherapy regimen and cancer-related knowledge quickly,improve the teaching qnality and the efficiency of treating malignant diseases.

Objective To survey membrane inhibitor of reactive lysis(MIRL) expression in non-small cell lung careinoma(NSCLC) and to analyze the relationship between MIRL expression and clinical staging, adjuvant chemotherapy and disease-free survial. Methods The expression of MIRL in 8 adjacent tissues and 36 NSCLC sam-pies were determined by immunohistochemistry. Furthermore, the relationship between MIRL expression and clinical stage ,adjuvant chemotherapy and disease-free survival was assayed by follow-up. Results Among 36 samples of non-small-cell lung cancer,there were 10(27.8%) samples expressing MIRE. Out of 18 samples of squamous carcinoma, 4(22.2%) expressed MIRL,while 6(37.5%) expressed it in 16 samples of adenocarcinoma,there was no statistical significance between them(P>0.05). There were no expression in 2 samples of large cell carcinoma. There was no correlation between MIRL expression and disease-free survival(P>0.05). MIRL positive expression rate in patients with preoperational adjuvant chemotherapy was significantly lower than that of those without preoperational adjuvant chemotherapy(P<0.05). Conclusions There is great percentage of MIRE expression in NSCLC. Our present study suggests that the immunological inhibition of MIRL should be blocked when monoclonal antibody is used in the treat-merit of NSCLC.

BACKGROUNDIt has been proven that the positive feedback gene circuits can increase the expression level of interested genes, and the synchronization of genetic circuits can further enhance the efficacy of gene therapy. In order to obtain an enhanced and prolonged gene expression in target cells, a radiation controlled positive feedback genetic circuit is constructed via linking the c-fos promoter with the inducible nitric oxide synthase (iNOS) cDNA, which can be synchronized by nitric oxide (NO) intercellular messenger. Ultimately, the efficacy of radiogenetic therapy for cancer will be improved.

METHODSUsing the gene recombination techniques, the vector pfos-iNOS/green fluorescent protein (GFP) was generated by cloning the radiation-responsive c-fos promoter into the plasmid vector pIRES2-EGFP to replace the primary CMV promoter, and then inserting human iNOS cDNA downstream of c-fos promoter in the vector pIRES2-EGFP. The constructed plasmids were then downloaded into A549 cells with lipofectamine. With exposure of various doses of ionizing radiation, outputs of GFP and iNOS in the treated cells were observed and analyzed.

RESULTSThe interested plasmid was successfully constructed, proved by restriction enzyme digestion analysis. The outputs of GFP and iNOS in the transfected cells were markedly increased compared with the control cells after radiation, the peak level was seen in 16 hours after radiation.

CONCLUSIONSA positive feedback genetic circuit is successfully developed, composed by c-fos promoter and iNOS cDNA, which can be synchronized by secreting the intercellular messenger NO. This genetic circuit will be utilized in further study.

Genetic circuits are collections of basic elements that interact to produce a particular behavior. By constructing biochemical logic circuits and embedding them in cells, one can extend or modify the behavior of cells. To date, several small synthetic gene networks have been built that accomplish specific genetic regulatory functions in vivo: the autorepressor, in which a repressor regulates its own production to reduce noise in gene expression; the toggle-switch, in which two repressors inhibit each other's production to achieve a bistable system; the repressilator, in which three repressors are connected in a ring topology to produce repeated oscillation. "Rational" and "directed evolution" are currently used Genetic-circuit design tools. Someday we may be able to program cell behavior as easily as we program computers.
Computer Simulation ; Gene Expression Regulation ; genetics ; Gene Regulatory Networks ; genetics ; Humans ; Models, Genetic

BACKGROUNDVascular endothelial growth factor-C(VEGF-C) plays a critical role in tumor-induced lymphangiogenesis and contributes to lymph node metastasis.Human antigen R(HuR) is one of the firstly identified RNA-binding proteins.It can increase the stability of a variety of growth factors and cytokines and upregulate protein expression.The aim of this study is to investigate the expression of HuR and VEGF-C protein in non-small cell lung cancer(NSCLC),and explore the relationship between the expression of HuR and VEGF-C and clinicopathological factors.

METHODSHuR and VEGF-C protein levels were detected in 81 NSCLC tissues and 15 control benign pulmonary lesion tissues by immunohistochemistry method(SP method).

RESULTSIn NSCLC tissues,positive rate of cytoplasmic HuR,nuclear HuR and VEGF-C was 45.7%(37/81),82.7%(67/81) and 70.4%(57/81),respectively.There was a significant difference in positive expression of HuR and VEGF-C between NSCLC and benign pulmonary lesion tissues(P < 0.05).The expression of cytoplasmic HuR was closely related to pTNM stages,differentiation degree and lymph node metastasis(P < 0.05),but not correlated with sex,age and histological classification(P > 0.05).Furthermore,cytoplasmic immunoreactivity for HuR protein(P < 0.05) but not nuclear HuR expression(P > 0.05) was associated with high VEGF-C expression.

CONCLUSIONSCytoplasmic HuR and VEGF-C are overexpressed in NSCLC,and are related to tumor development.HuR may mediate the modulation of VEGF-C gene expression in NSCLC.

BACKGROUNDAs a new member of inhibitor of apoptosis protein(IAP) family,Livin,especially Livin α,is known to be involved in occurrence and development of lung cancer.Livin is an important mechanism of chemotherapy resistance of lung cancer cell.The aim of this study is to set up Livin isoform(α & β)-specific gene silencing system in SPC-A1 cells by gene transfection and RNA interference(RNAi),and to explore the different functions and value of the isoforms in enhancing chemosensitivity of SPC-A1 cells.

METHODSLivinα+β,Livinα and Livinβ specific siRNA were expressed stably in SPC-A1 cells,respectively.MTT was performed to study sensitivity of the cells to chemotherapy drugs.In vivo experiment was performed to test sensitivity of mouse bearing tumor to cisplatin after gene silencing of Livin.

RESULTSAfter silencing of Livinα+β,Livinα and Livinβ genes,sensitivity of SPC-A1 cells to many chemotherapy drugs(including cisplatin,carboplatin,cyclophosphamide and adriblastine) was markedly increased(P < 0.05).Among them,gene silencing of Livinα+β showed the strongest enhancement effect on chemosensitivity of SPC-A1 cells(P < 0.01).Animal experiment showed that tumor inhibition rate of pSilencer-Livinα+β,pSilencer-Livinα and pSilencer-Livinβ groups was 146.1%,130.7% and 110.5%,respectively.

CONCLUSIONSThe results suggest that Livin isoform,especially Livinα+β is hopeful to be a molecular target for increasing sensitivity of lung cancer cell to chemotherapy.Gene silencing may be a new means of gene therapy for non-small cell lung cancer.

BACKGROUNDGensing Rg3 is an active component from ginseng. The aim of this study is to observe the clinical anticancer effect of Rg3 in combination with chemotherapy regimen NP (vinorelbine+cisplatin) in advanced non-small cell lung cancer (NSCLC).

METHODSStage III-IV NSCLC patients confirmed by pathology or cytology all received vinorelbine plus cisplatin for at least two cycles, and were randomized into two groups: patients in arm A also received placebo twice a day, while patients in arm B received two tablets of Rg3 twice a day for at least two months. The endpoints of the study were the efficacy, survival and tolerance of patients.

RESULTSFrom July 2000 to May 2002, 115 patients were enrolled into the trial. The patients' characteristics were well balanced in the two groups. Sex of patients: male, 79; female 36. Types of pathology: adenocarcinoma, 71; squamous cell carcinoma, 29; adenosquamous carcinoma, 8; others, 7. TNM stage: stage III, 45; stage IV, 70. Prior chemotherapy: with, 17; without, 98. Prior radiotherapy: with, 15; without, 100. Prior surgical treatment: with, 23; without, 92. Nine patients discontinued from the trial due to severe adverse effects (5) and other reasons (4), so there were 106 patients evaluable for clinical efficacy. The response rate was 14.5% (8/55) in arm A, and 33.3% (17/51) in arm B (P=0.011). The survival time in arm A was 9.7 months (mean) and 8.0 months (median), and 15.3 months (mean) and 10.0 months (median) in arm B (P=0.0088).

CONCLUSIONSPreliminary results show improvements in response rate and survival time (median and mean) in Rg3 arm compared with placebo arm. It is worthy to confirm the results in further clinical trials.

BACKGROUNDIt has been proved that hyaluronan was involved in adhesion and invasion behavior of varied tumor cells. Layilin is a receptor of hyaluronan found recently and has close relationship with cytoskeleton. The aim of this study is to investigate the effect of short hairpin RNA (shRNA) targeting layilin on adhesion and invasion behavior of human lung adenocarcinoma cell line A549 induced by hyaluronan in vitro.

METHODSRNA interference plasmid that included U6 promoter and could express shRNA targeting layilin was designed, constructed, and transfected into A549 cell line. Layilin expression was examined by RT-PCR, Western blot and immunofluorescence. Adhesive and invasive ability was examined by plate adhesion model and Boyden chamber model.

RESULTSAfter plasmid transfected, layilin expression in A549 cells obviously decreased (P < 0.01), and the numbers of adhesive A549 cells on plate and A549 cells permeating septum of Boyden chamber induced by hyaluronan also significantly decreased (P < 0.01).

CONCLUSIONSThe shRNA targeting layilin can efficiently inhibit the adhesive and invasive ability of A549 cells induced by hyaluronan in vitro.