It is proved that there are significant differences in individual susceptibility to lung cancer.Genetic polymorphisms of several enzymes involved in the detoxification and biotransformation might be related to the lung cancer susceptibility.Cytochromes P450,N-acetyltransferases,microsomal epoxide hydrolase,NQO1 are the most frequently investigated genes in recent years.All theses genes appear to be the candidates for lung cancer susceptibility genes.The studies of the relationship between polymorphisms of metabolic enzymes and lung cancer susceptibility will help to find useful biomarkers.An improved understanding of genetic polymorphisms may help to identify individuals who are at increased risk for lung cancer and decrease the incidence of lung cancer.

Objective To investigate the expression of Sonic hedgehog(SHH)and WNT/β-cate-nin in human pancreatic cancer and explore its clinical significance.Methods Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot assay were used to determine the mRNA and protein expression of SHH and β-catenin in human pancreatic cancer tissue and normal tissues adjacent to cancer.Results The SHH mRNA and protein expression was detected in 81.6% and 79.6% of pancreatic cancer, respectively.The β-catenin protein expression was 71.4% in pancreatic cancer tis-sues.These were significantly different from those of normal tissue adjacent to cancer (P＜0.05).But the expression level of β-catenin mRNA was low in both pancreatic cancer tissues and normal tissues.There was no significant difference between them (P＞0.05).The expression of SHH and β-catenin protein in pancreatic cancer had no correlation with age, tumor size, pathological type and tumor site (P＞0.05), but had a relationship with lymph node metastasis and TNM stage (P＜0.05).The cor-relation between SHH and β-catenin protein was positive (r=0.352, P＜0.05).Conclusion The SHH and WNT/β-catenin signaling pathways were active in human pancreatic cancer.The crosstalk between these pathways may play an important role in the carcinogenesis and development of pancreat-ic carcinoma.

Objective To construct and identify recombinant adenovirus vectors expressing GFP and human vascular endothelial growth factor (VEGF) iRNA and to inhibit the gene expression of VEGF in human nasopharyngeal carcinoma cell line CNE with the RNA interference (RNAi) technique,and explore the expression of VEGF in CNE and its proliferation before and after transfection.Methods By the method of restriction endonuclease digestion,the GFP and human VEGF genes were subcloned from pGenesil-1 plasmid into the shuttle vector pGSadeno-GFP-VEGF.After correct identification of the recombinant plasmid pGSadeno-GFP-VEGF,it was then digested by Pacl and transfected into HEK293 cells to be packaged and amplification for rAd-VEGF.Meanwhile,the recombinant adenovirus was identified by PCR method.The expression of GFP was detected to evaluate the titre and transfective ratio.Results Digestion and PCR identification showed the construction of recombinant adenovirus rAd-VEGF was successful via LR recombinant.The titre was 2×109 PFU/ml while the transfective ratio in CNE cell line was more than 90 percent which met the need of experiment.Cell growth was inhibited compared with non-siRNA transfected CNE cell line.Conclusion The recombinant virus expressing GFP and VEGF are successfully constructed; it layed a foundation for further relevant study.

Objective To evaluate the efficacy of amifostine in diminishing the incidence of radiation‐induced pneumonitis in patients with non‐small cell lung cancer (NSCLC)by using the meta‐analysis.Methods Medline ,Embase ,Cenfang ,CNKI , CBM ,Wanfang ,ASCO ,and ESMO databases were searched for randomized controlled trials(RCTs)on use of amifostine during radiotherapy for NSCLC and the papers were published before February 2015.Meta‐analysis was used to evaluate the efficacy of amifostine in decreasing the incidence of radiation‐induced pneumonitis.Results A total of 8 RCTs were identified with 394 ca‐ses in amfostine group and 402 in control group.The pooled relative risk(RR)of developing radiation‐induced pneumonitis(grade≥3)was 0.50(95% CI:0.37 -0.69 ,Z=4.33 ,P<0.01)in amfostine group when compared with control group.Conclusion Amifostine can significantly decrease the risk of developing radiation‐induced pneumonitis in NSCLC patients treated by radio‐therapy.

As the leading cause of death among lung cancer patients, brain metastasis occurs in approximately 10 percent of non-small cell lung cancer (NSCLC) patients at first diagnosis.Whole-brain radiation therapy (WBRT) is still the standard treatment for patients with brain metastasis, however, the efficacy of WBRT reaches a plateau.It has been proved that tyrosine kinase inhibitors (TKIs) make considerable therapeutic effect for NSCLC patients with brain metastasis.The combination therapy of TKIs with WBRT may provide new major treatment for epidermal growth factor receptor (EGFR) mutant NSCLC with brain metastasis.

Objective To measure the distortion of digital images generated by radiotherapy simula-tor,and to study the appropriate method of correction. Methods The grid correction plate and Microsoft Visual C + + 6.0 were used for correction. The area error and boundary maximum displacement error of dig-ital images before and after correction were calculated. The post-correction images were compared with film images to evaluate the correction method. Results The area error was 0.31% - 12.36%, and the bounda-ry displacement error was more than 0 -6 mm for 4 cm ×4 cm - 12 cm × 12 cm radiation field before correc-tion. For commonly used radiation field(12 cm × 12 cm) ,the post-correction area error and the boundary displacement error were 0.48% and 0.46 mm,respectively. Conclusions The least square and polynomi-al fitting correction method can fulfill the requirement of conventional radiotherapy.

Objective To investigate the regulatory effects of PTEN-PI3K/AKT pathway on the apoptosis of gastric cancer MKN28 cells and the possible mechanisms.Methods The specific sequence of PTEN was transfected to MKN28 cells by eukaryotic expression vector (transfection group),and then vacant vector (negative control group) and PBS (blank control group) were transfected to the MKN28 cells,respectively.The effects of PTEN-PI3K/AKT pathway on the apoptosis of MKN28 cells and the expressions of PI3K,AKT,Caspase-3 and Caspase-9 were investigated.The growth curve and apoptosis of the MKN28 cells were detected by MTT assay and TUNEL staining,respectively,and the protein expression was detected by the Western blot.MKN28 cells which did not transfected by the PTEN were processed by inhibitor of PI3K (LY294002) (treated group),and MKN28 cells in the control group were processed by PBS.The expressions of apoptosis protein and apoptosis-related protein were detected after inhibition of PI3 K.All data were analyzed using the t test.Results The model of over-expression of PTEN was obtained and transfected into MKN28 cells.The survival of MKN28 cells in the transfection group was significantly inhibited in a time-dependant manner ( r =0.938,P ＜ 0.05 ).The mean apoptotic rate of the transfection rate was 27.86％ ± 4.78％,which was significantly higher than 0.01％ ± 0.01％ of the negative control group ( t =9.527,P ＜ 0.05 ).The protein expression of PI3K in the transfection group was 0.25 ± 0.03,which was significantly lower than 0.93 ± 0.16 of the blank control group and 0.96 ± 0.15 of the negative control group (t =7.235,8.883,P ＜ 0.05 ).The protein expression of P-AKT in the transfection group was 0.21 ± 0.03,which was significantly lower than 0.93 ± 0.13 of the blank control group and 0.91 ± 0.12 of the negative control group (t =9.347,9.802,P ＜ 0.05 ).The expressions of Caspase-3 and Caspase-9 of the transfection group were 0.86 ± 0.11 and 0.87 ± 0.12,which were significantly higher than 0.16 ± 0.03 and 0.18 ± 0.04 of the negative control group,and 0.15 ± 0.02 and 0.16 ± 0.03 of the blank control group ( t =10.634,10.999,9.448,9.942,P ＜0.05).The apoptotic rate of the MKN28 cells of the treated group was 28.60％ ± 4.50％,which was significantly higher than 0.12％ ± 0.06％ of the control group (t =10.961,P ＜ 0.05 ).The protein expression of PI3K and P-AKT of the treated group were 0.18 ± 0.02 and 0.11 ± 0.01,which were significantly lower than 0.93 ± 0.14 and 0.90 ± 0.12 of the control group (t =9.186,11.363,P ＜ 0.05 ).The protein expression of PTEN of the treated group was 1.15 ± 0.15,which was significantly higher than 0.21 ± 0.08 of the control group (t =9.577,P ＜ 0.05 ).The relative expressions of Caspase-3 and Caspase-9 of the treated group were 0.86 ± 0.12 and 0.88 ± 0.11,which were significantly higher than 0.25 ± 0.02 and 0.21 ± 0.03 of the control group (t =8.685,10.178,P ＜ 0.05).Conclusions Over-expression of PTEN may enhance the apoptosis of gastric cancer cells through inhibition of PI3K/AKT pathway.Inhibition of PI3K can enhance the expression of PTEN.PI3K and PTEN regulate the apoptosis of gastric cancer cells.

Objective To investigate the impact of accelerator′s multi-leaf collimator (MLC) on the radiotherapy dose with different gantry angles.Methods Measured with Mapcheck 2D diode array and 30 cm×30 cm×3 cm solid water, Pre-selecting the 30 appropriate single fields and 0°,45°,90°,270°,315° gantry angles of static and dynamic intensity modulated radiation therapy (IMRT), quantification analysis of the passing rate with MapCheck γ(3%/3 mm) and (5%/3 mm) analysis methods, and the same method to 30 examples static and dynamic IMRT plans.Results When the accelerator collimator angle is 0°,the 30 appropriate single fields′ passing rate of between 0°gantry angle and 45°,90°,270°,315°gantry angles of static and dynamic IMRT accordingly is 97.71% and 96.25%(t=1.70, P=0.389), 96.34% and 93.72%(t=2.95, P=0.002), 96.65% and 92.98%(t=2.87, P=0.005), 95.87% and 93.15%(t=2.71, P=0.006), 96.09% and 93.51%(t=2.89, P=0.004) with MapCheck γ(3%/3 mm) analysis methods, however, the passing rate also does not have the difference, respectively is 99.31%-99.73% and 98.89-99.68%(t=0.57-1.90, P=0.913-0.725) with MapCheck γ(5%/3 mm) analysis methods;the passing rate of 30 examples static and dynamic IMRT plans accordingly is 96.11%-96.76% and 94.88%-95.78%(t=1.02-1.61, P=0.317-0.235).Conclusions When the accelerator collimator angle is 0°, at different gantry angles, MLC leaves due to gravity, friction, inertia, etc caused by errors in place, the physical penumbra and leakage radiation will indeed affect the IMRT dose, however, the deviation of dose distribution is within acceptable 5%.

The therapeutic approaches for non-small cell lung cancer (NSCLC)patients with solitary bone metastases include surgery,radiotherapy,chemotherapy and so on.Recently,molecular targeted therapy such as the Denosumab has become a new option.Though there are so many options,the outcomes of the NSCLC with bone metastases are not so good.But for those with solitary bone metastases,radical treatment is necessary to improve the survival time and prognosis.

Cancer associated fibroblast (CAF) is the most important component in the tumor environment,and some researchers even propose that CAF can be the new target in cancer therapy.However what make it difficult for researchers are the various origins of the CAF,such as resident fibroblast,epithelium,endotheliocyte,mesenchymal cell,stem cell and so on.The various origins define their different phenotypes and functions.Further understanding about the origins of the CAF will help us to explore a novel approach for cancer therapy.