ObjectiveTo explore the effect of silencing the expression of four and a half LIM domains protein 2 （FHL2） on the proliferation and apoptosis of osteosarcoma U2OS cells and its mechanism by shRNA. MethodsFHL2 was knocked down in U2OS cells by constructing the shRNA interference carrier PLKO.1 of FHL2. The lentivirus was prepared and infected with U2OS cells， which were divided into shFHL2 target gene interference group （shFHL2） and unrelated sequence control group （SCR）. At 96 h after transfection， realtime quantitative PCR （QPCR） and Western blotting were used to detect the mRNA and protein levels of FHL2 in two groups. MTT assay and flow cytometry were performed to detect the proliferation， cell cycle distribution and apoptotic rate of U2OS cells. Western blotting was used to analyze the level of cell cycle and apoptoticrelated proteins. Dual luciferase assay was conducted to investigate the transcriptional activity of p53 on Bax when FHL2 was overexpressed or was knocked down. 
ResultsAt 96 h after transfection， the mRNA and protein levels of FHL2 in shFHL2 group were significantly lower than those in SCR group （P＜0.05）. The proliferative ratios of shFHL2 group at 24， 48， 72 and 96 h after transfection were 173±008， 249±038， 326±045 and 428±029， and the data of 96 h was lower than SCR group （P＜0.05）. The apoptotic rate of shFHL2 group at 96 h after transfection was （17.55±1.05）％， higher than （7.73±1.12）％ of SCR group （P＜0.05）. The proportion of shFHL2 group cells in G0／G1 phase at 96 h after transfection was （68.18±0.78）％， higher than （59.73±2.28）％ of SCR group， and the difference was statistically significant （P＜0.05）. Western blotting showed that the level of cell cyclerelated protein p21 and proapoptotic protein p53 and Bax increased. Dual luciferase assay suggested that p53 could increase the transcriptional activity of Bax， furthermore， when FHL2 was knocked down at the same time， the transcriptional activity of p53 was enhanced. ConclusionCell proliferation reducing， cell cycle arresting at G0／G1 phase， and cell apoptosis increasing occurred in FHL2 knockdown U2OS cells. Moreover， FHL2 participated in the regulation of the transcriptional activation function of p53. These results indicated that FHL2 might be a novel potential target for osteosarcoma treatment.

ObjectiveTo construct a recombinant short hairpin RNA （shRNA） lentiviral vector of cyclooxygenase 2 （COX2） gene， and investigate its effects on proliferation and apoptosis of nonsmall cell lung cancer （NSCLC）. 
MethodsThree oligonucleotides targeting COX2 gene were synthesized and cloned into lentivirus vector GV248. The lentivirus vector COX2shRNA targeted to COX2 gene was constructed and screened for the best inhibition efficiency. The human NSCLC A549 cells were selected for lentivirus transfection during the logarithmic growth period. Specially， shRNA vector targeting COX2 gene was transfected into A549 cells as shRNA group， and empty vector plasmid was transfected as negative control （NC） group. A549 cell without transfection plasmid were selected as blank control group （CON）. COX2 expressions were assessed by realtime PCR and Western blotting. The effects of interfering COX2 expression on the proliferation and apoptosis of A549 cells were detected by MTT and flow cytometry. 
ResultsThe recombinant lentivirus vector targeting COX2 was constructed successfully. Especially COX2shRNA1 showed the best transfection efficiency. In shRNA group， the level of COX2 mRNA in shRNA1 transfected A549 cells was 017±006， lower than 081±011 of NC group and 109±007 of CON group （P＜0.05）. The proliferative activity of shRNA group was lower than those of NC group and CON group. For example， the absorbance value at 5 d in shRNA group was 0976±0016， which was lower than 1.557±0.015 of NC group and 1.880±0.034 of CON group （P＜0.05）. The apoptotic rate of shRNA group was （6.28±0.31）％， which was higher than （3.08±0.05）％ of NC group and （3.01±0.31）％ of CON group， and the difference was statistically significant （P＜0.05）. 
ConclusionThe recombinant lentivirus shRNA vector target COX2， with best transfection efficiency， is constructed successfully. RNAimediated silencing of the COX2 gene can inhibit the proliferation of A549 cells and promote its cell apoptosis.

ObjectiveTo investigate the effect of microRNA3917 （miR-3917） on the proliferation of lung cancer cells and the expression of biological clock gene Period2 （PER2）. 
MethodsThe recovered A549 cells were cultured to logarithmic growth phase. The pEGFPmiR3917siRNA plasmid vector targeting miR3917 was transfected into A549 cells by 10， 20 and 50 nmol／L liposome. The expression of green fluorescent protein was observed under fluorescence microscope after 48 h transfection. According to the experimental design， they were divided into control group， empty load group and interference group. The plasmid concentration in empty load group and interference group was 50 nmol／L. The realtime quantitative PCR （QPCR） was used to detect the relative expression of miR3917 at 48 h after transfection. The mRNA and protein levels of PER2 were detected by QPCR and Western blotting after at 48 h after transfection， respectively. The inhibitive rates of proliferation at 24， 48 and 72 h after transfection were detected by CCK8 assay. Dual luciferase target assay was employed to verify that PER2 was a direct target of miR3917. 
ResultsThe relative expression levels of miR3917 in control group， empty load group and interference group were 1.007±0.018， 1.068±0.084 and 0171±0.052. The relative expression level of miR3917 in the interference group was lower than that in the control group and empty load group， and the difference was statistically significant （P＜0.05）. The relative expression levels of PER2 were 1.060±0.129， 1.086±0.229 and 2.920±0.927 in the control group， empty load group and interference group， and the protein levels were 0.204±0.046， 0.183±0.043 and 0.512±0.117. The mRNA and protein levels of PER2 in the interference group were higher than those in the control group and empty load group， and the difference was statistically significant （P＜0.05）. Compared with the control group and empty load group， the proliferative ability decreased in interference group. The inhibitive rates of proliferation were （34.192±5.268）％， （33.527±6.603）％ and （30.591±7.788）％ at 24， 48， 72 h in interference group， higher than other two groups， and the difference was statistically significant （P＜0.05）. miR3917 could significantly inhibit the luciferase activity of wildtype PER23’UTR plasmid transfected cells， but had no significant effect on the luciferase activity of mutant PER2-3’UTR plasmid transfected cells. 
ConclusionDownregulation of miR3917 can inhibit the proliferation of lung cancer cells and increase the expression of PER2. miR-3917 has a targeted regulation effect on PER2， and can be used as a new target for the prevention and treatment of lung cancer.

ObjectiveTo explore the effect of microRNA216 （miR-216） on the proliferation and apoptosis of pancreatic cancer cells and the drug resistance to gemcitabine. 
MethodsThe realtime quantitative PCR （QPCR） method was used to detect the miR216 level in the gemcitabine resistant cell line BxPC3 and the nondrugresistant cell line CFPAC1 of pancreatic cancer. The miR216 mimics （mimics group） and inhibitor （inhibitor group） were transfected to BxPC3 cells by Lipofectamine 2000 liposome method. BxPC3 cells transfected with liposomes were used as the control group. QPCR was used to detect the level of miR216 at 48 h after transfection. The CCK8 method was used to detect the absorbance of each group at 24， 48， and 72 h after transfection to evaluate the proliferation rate. Annexin ⅤFITC／PI double staining was used to detect the apoptotic rates of each group at 48 h after transfection. The CCK8 method was used to detect the half inhibitory concentration （IC50） of gemcitabine. The target gene of miR216 was predicted by bioinformatics database miRBase and Gene Oncology （GO） function was annotated by cytoscape 351 and its plugin CluGO. 
ResultsThe results of QPCR detection showed that the level of miR216 in BxPC3 cells was 3010±0901， higher than 1049±0074 of CFPAC1 cells （P＜0.05）. The expression levels of miR216 in the control group， mimics group and inhibitor group were 1130±0.145， 4.843±0.782 and 0.256±0145（P＜0.05）. Compared with the control group， the proliferative rates increased and apoptotic rates decreased in mimics group while the proliferative rates decreased and apoptotic rates increased in inhibitor group （P＜0.05）. The IC50 of gemcitabine were （2.134±0.591）μg／ml， （4.518±0.862）μg／ml and （0481±0073）μg／ml in the control group， mimics group and inhibitor group. The resistance of BxPC3 cells to gemcitabine decreased after transfection of miR216inhibitor， and the resistance to gemcitabine increased after transfection of miR216mimics （P＜0.05）. There were 138 predicted target genes of miR-216. GO functions are mainly enriched in proliferation， apoptosis， invasion and migration. 
ConclusionThe expression of miR216 is upregulated in pancreatic cancer drug resistant cells and can induce the proliferation of cancer cells， suggesting that it can play a similar role in promoting tumor genes and participate in the process of gemcitabine resistance， and it may become a target for early diagnosis and new biological treatment of pancreatic cancer.

ObjectiveTo investigate the clinical value of detection of combined secreted frizzledrelated proteins 1 （SFRP1） and septin 9（SEPT9） gene methylation in stool DNA for early diagnosis of elderly colorectal cancer （CRC）. 
MethodsThirtyfive patients with CRC who were aged over 60 years from January 2016 to September 2016 were inrolled in the study. At the same time， 35 normal people， who passed the physical examination and were aged over 60 years， were selected as the control group. DNA in the stool of CRC and normal subjects was extracted. Methylation specific PCR （MSP） technique was used to detect the methylation status of SFRP1 and SEPT9 genes respectively. The difference of detection rate of single gene and double gene methylation in CRC patients was compared， and the detection rate of combined double gene methylation in CRC patients was compared with that in normal control group. The correlation between the methylation of SFRP1 or SEPT9 gene in CRC patients and the clinicopathological parameters， such as age， sex， and tumor location， was analyzed. 
ResultsThe detection rates of methylation of SFRP1 and SEPT9 genes in stool DNA of CRC patients were 45.71％ （16／35） and 51.43％ （18／35）， respectively， which were significantly higher than those in control group 857％ （3／35） and 14.29％ （5／35）， and the differences were statistically significant （P＜0.01）. There was at least one gene methylation in the stool DNA of 82.86％ （29／35） CRC patients， which was significantly higher than the single gene detection rate （P＜0.01）， which was also higher than that of the control group 17.14％ （6／35）， the difference was statistically significant （P＜0.01）. The methylation of SFRP1 or SEPT9 genes in CRC patients was not related to age， sex and tumor location （P＞0.05）. 
ConclusionThe methylation test of SFRP1 and SEPT9 genes in stool DNA is more sensitive than single gene detection， which is of great value in the early diagnosis of elderly colorectal cancer.

ObjectiveTo study the changes of programmed death factor-1／programmed death factor-1 ligand （PD-1／PD-L1） in patients with myelodysplastic syndrome （MDS） before and after using decitabine （DAC）. MethodsFrom Jan 2016 to Jan 2017， 18 cases newly diagnosed as MDS with WHO 2008 type WPSS prognostic stratification in middlerisk group and highrisk group were enrolled. Patients were applied with DAC （20 mg／m2 d1~d5， 21~28 days as a cycle） for 2 cycles. Five patients with nonmalignant hematologic diseases were treated as control. Peripheral blood and bone marrow cells were collected before and after DAC application for 2 cycles. FCM was used to determine PD1 of CD3+CD4+T and CD3+CD8+T cells in peripheral blood lymphocytes and PDL1 in bone marrow progenitor cells before and after treatment with DAC. The relative expression of PD1mRNA and PDL1mRNA in peripheral blood and bone marrow mononuclear cells before and after DAC treatment was detected by QPCR. PD1／PDL1 level was compared between remission group （n=5）and nonremission group（n=13）. ResultsFCM analysis showed that the proportion of PD1of CD3+CD4+T and CD3+CD8+T lymphocytes， and PDL1 of bone marrow monounclear cells in middlerisk group after DAC treatment was （11.43±1.88）％， （11.46±1.60）％ and （16.59±0.72）％， and the data in highrisk group after treatment were （16.36±3.71） ％， （16.59±3.81）％ and （18.69±1.60）％， all higher than those before treatment and those of control group （P＜0.05）. The proportion of PD1 of CD3+CD4+T and CD3+CD8+T lymphocytes， and PDL1 of bone marrow mononuclear cells in nonremission group was （18.51±2.62）％， （1903±2.18）％ and （19.22±1.40）％， higher than those in remission group （P＜0.05）. QPCR analysis showed that after DAC treatment the relative expression of PD1 mRNA in peripheral blood and PDL1 mRNA in bone marrow mononuclear cells of middlerisk group was 6.32±3.37 and 2.88±1.72， and they were 1255±627 and 7.47±4.90 in high risk group， higher than those before treatment （P＜0.05）. The relative expression of PD1 mRNA of peripheral blood mononuclear cells and PDL1 mRNA of bone marrow mononuclear cells in nonremission group was 1628±464 and 9.16±5.40， significantly higher than those in remission group （P＜0.05）. 
ConclusionAfter treatment with DAC， the expression of PD1／PDL1 in peripheral blood and bone marrow of MDS middlerisk， highrisk patients increased significantly， especially in nonremission group. High expression of PD1／PDL1 may be one of the reasons leading to drug resistance of DAC.

ObjectiveTo investigate the clinical significance of the expression of laminin5 （LN5） in lung adenocarcinoma and its relationship with mutations of epidermal growth factor receptor （EGFR）. 
MethodsFrom January 2015 to December 2015， specimens from 57 cases of lung adenocarcinoma and adjacent normal tissues with pathological confirmation after surgical resection were collected. LN5 expression was detected using immunohistochemical SP methods， and EGFR mutations were assessed using liquichip technology. The expression of LN5 and its relationship with EGFR mutations were analyzed. 
ResultsThe positive expression of LN5 in adenocarcinoma tissues was 21.1％ （12／57）， higher than 1.7％ （1／57） of adjacent normal tissues （P＜0.05）. The incidence of EGFR mutations （E19+E21） was 43.9％ （25／57）， while that of wild type+E20 was 561％ （32／57）. The expression of LN-5 was associated with lymph node metastasis and EGFR mutation （P＜0.05）， but not with TNM stage （P＞0.05）. There was a negative correlation between the expression of LN-5 and EGFR mutation（r=-0.283，P＜0.05）. 
ConclusionThe expression of LN5 is upregulated in lung adenocarcinoma and is correlated with EGFR mutation status.

ObjectiveTo investigate the expression of p16INK4a protein in human cancers and analyze its clinical significance. 
MethodsA total of 642 cases surgical specimens of primary human tumors from 2014 to 2015 were underwent operations in the study. Immunohistochemical staining was used to detect and analyze the expression of p16INK4 in tumor tissues. 
ResultsOf the 642 tumor samples， 120 were benign and 522 were malignant. The expression rates of p16INK4a negative（-）， weak positive（+）， moderately positive（++） and strong positive（+++） were 1743％ （91／522）， 11.11％ （58／522）， 19.16％ （100／522） and 52.30％ （273／522） in malignant tumor tissues， respectively； while in benign lesions， the expression rates were 3417％ （41／120）， 2333％ （28／120）， 26.67％ （32／120） and 1583％ （19／120）， respectively. The difference was statistically significant （P＜0.05）. The positive expression rate of p16INK4a protein in different tissues derived tumors was not the same （P＜0.05）.Using p16INK4a protein as a biological molecules marker of malignant tumor， the sensitivity and specificity and positive predictive value of it were different as choosing different positive cell value. While using moderately positive as positive value， the sensitivity， specificity and positive predictive value were 71.46％， 57.50％ and 87.97％. While using strong positive as positive value， the sensitivity， specificity and positive predictive value were 52.30％，84.17％ and 93.49％. 
ConclusionThe compensatory high expression of p16INK4A is a tumor specific immune phenotype， which is related to the abnormal cell cycle patterns of tumor， and can be used as a molecular marker for the diagnosis， differential diagnosis and molecular typing of malignant tumors.

ObjectiveTo explore the independent prognosis factors of longterm survival for patients of advanced duodenal cancer and evaluate the efficacy and safety of its firstline chemotherapy. 
MethodsFrom June 2008 to January 2016， a total of 40 advanced duodenal cancer patients were analyzed. Only 31 patients received chemotherapy， including 13 patients of GEMOX regimen， 13 patients of FOLFOX regimen， 2 patients of capecitabine regimen and 3 patients of gemcitabine regimen. The efficacy and safety were evaluated by RECIST 11 and NCICTC 40 criteria. Survival analysis was performed by using KaplanMeier method. Univariate analysis of prognosis was made by Logrank method. Multivariable analysis of prognosis was used by Cox proportional hazard regression model. 
ResultsThe total treatment cycle of chemotherapy was 146， and the median treatment cycle was 4（2.12 cycles）. CR was not observed. For GEMOX regimen， 1 case of PR and 10 cases of SD and 2 cases of PD were observed with disease control rate（DCR） of 84.6％. For FOLFOX regimen， 6 cases of SD and 7 cases of PD were observed with DCR of 46.2％. For capecitabine and gemcitabine regimen， 3 cases of SD and 2 cases of PD were observed with DCR of 60.0％. The median overall survival （OS） of chemotherapy and nonchemotherapy were 15.7 months and 4.4 months（P＜0.001）. The median OS of GEMOX， FOLFOX regimen and single drug group were 27.9 months， 15.2 months and 15.2 months（P=0656）. The median progressionfree survival （PFS） of GEMOX， FOLFOX regimen and single drug group were 7.8 months， 4.0 months and 51 months（P=0.053）. The major treatmentrelated side effects including leucopenia， neutropenia， anemia， fatigue， nausea and etc， were mainly in grade 12. In univariate analysis， depth of invasion， degree of differentiation， liver metastasis and chemotherapy correlated with the prognosis of the patients of advanced duodenal cancer （P＜0.05）. Multivariable analysis revealed that degree of differentiation， liver metastasis and chemotherapy were independent risk factors of prognosis. 
ConclusionGEMOX， FOLFOX， capecitabine and gemcitabine regimen were effective and welltolerated in firstline chemotherapy. GEMOX regimen may have a longer OS and PFS in firstline chemotherapy. Degree of differentiation， liver metastasis and chemotherapy may serve as dependent prognostic factors with advanced duodenal cancer， which can be used to guide the choice and practice of the therapy for advanced duodenal cancer.

ObjectiveTo investigate the efficacy and safety of S1 combined with oxaliplatin as firstline treatment for metastatic colorectal cancer（mCRC）. 
MethodsA wide search of randomized clinical trials （RCT）using S1 combined with oxaliplatin as a firstline therapy for mCRC patients was performed in the Cochrane Library， PubMed， EMBASE， MEDLINE， CNKI and WanFang databases. All included studies were assessed according to the guidance of the Cochrane Collaborations tool for assessing risk of bias of RCTs， and then statistical analyses were performed using Rev Man 53 software. 
ResultsA total of 5 RCTs involving 1382 patients were included. Meta analysis indicated that the progressionfree survival（HR=0.90，95％CI：0.801.02，P=0.10）， overall survival（HR=1.14，95％CI：0.981.31，P=0.08）， objective response rate（RR=1.12，95％CI：0.871.43，P=0.38）， disease control rate（RR=104，95％CI：0.981.10，P=0.24）， showed no statistical significance between S1 combined with oxaliplatin and oxaliplatin combined with 5FU or capecitabine. For side effects， S-1 combined with oxaliplatin could decrease incidence of grade 34 leukopenia， but increased the incidence of grade 3.4 stomatitis， anorexia， diarrhea. There were no statistical difference between the two regimen in the incidence of neutropenia， anemia， thrombocytopenia， nausea， vomiting and fatigue. 
ConclusionS1 combined with oxaliplatin seem to have similar efficacy in the firstline treatment for mCRC with different toxicity. The S-1 may offer an alternative to 5-FU.

ObjectiveTo investigate the clinical efficacy and safety of apatinib in the treatment of gastric cancer and esophagogastric junction adenocarcinoma with liver metastases. 
MethodsFrom Mar. 2011 to Feb. 2017， 42 cases of gastric cancer and esophagogastric junction adenocarcinoma with liver metastases including 18 newly diagnosed patients and 24 relapsed refractory patients were analyzed retrospectively. The oral dose range of apatinib was 250850 mg and the appropriate dose adjustment could be made according to the patients physical status and side effects. Combined chemotherapy regimens included single drug S.1， XELOX regimen， SOX regimen， and hepatic artery and gastric artery chemoembolization （TACE）. The efficacy and adverse effects were respectively evaluated by RECIST 1.1 and NCICTCAE 4.0 criteria. The relationship between the clinicopathologic features with clinical efficacy was analyzed. The followedup was performed and Cox regression model was used for multifactor survival analysis. 
ResultsIn the combined chemotherapy group， the median chemotherapy cycle was 4 （2.6）， and the median chemotherapy cycle in the TACE group was 3 （1.3）. There were 3 patients （7.14％） of PR， 22 （52.38％） cases of SD and 17 （40.48％） cases of PD. The total response rate （RR） was 7.14％， and the disease control rate （DCR） was 5952％. With a median followup time of 4（1.16） months， the median overall survival （OS） was 7 months and the median progressionfree survival （PFS） was 2 months. The clinicapathologic features such as gender, age, primary lesion, gastrectomy, TACE and chemotherapy with different initial does of apatinib was not related to RR or DCR（P＞0.05）. Independent prognostic factors of PFS was not found in survival analysis. Apatinib combined with chemotherapy was independent factor of OS. Apatinib monotherapy was associated with a higher risk of death than combined chemotherapy. The side effects included leukocyte decline， anemia， thrombocytopenia， hand foot syndrome， hypertension， fatigue and diarrhea. Most of adverse reactions were in 12 grade, whose incidence was low and tolerable. 
ConclusionApatinib combined with chemotherapy in the treatment of gastric cancer and esophagogastric junction adenocarcinoma with liver metastases was clinical efficacy， and can significantly extend the survival time.

Melanoma is the most aggressive form of skin tumor caused by excessive proliferation of the abnormal melanocytes with an increasing incidence in recent years in China. However， patients with advanced melanoma had very poor prognosis by traditional therapies. The discovery of prevalent BRAF V600 mutation driving proliferation offers an opportunity to test this oncogenetarget therapy for melanoma. Since 2011， the development of BRAF inhibitor significantly improved the outcome of advanced melanoma treatment， which have brought a hope to the advanced melanoma therapy. This article reviews the mechanism and the current clinical application of BRAF inhibitor from clinical trials in advanced melanoma. In addition， this review will also focus on safety of BRAF inhibitor and treatment selection to obtain maximal benefit in clinical practices.

Resently， many studies have shown that different circRNA can act as a special noncoding RNA which binds to specific miRNAs to play sponge activity. Through this way can inhibit miRNA function， and also affect the relevant pathways and the occurrence and development of specific tumors. The biogenesis， properties and functions of endogenous circulatory sponges were summarized by collecting experimental studies， and the effects of circRNA sponge and human tumor development were reviewed.

The patientderived tumor xenograft （PDTX） model is developed by implanting fresh tumor tissues into immunodeficient mice and relying on the microenvironment provided by the mice. This model retains the principal pathophysiological characteristics， histological and phenotypic characteristics of donor tumors， maintains the matrix and stem cell composition of tumor cells， and replaces patients with preclinical studies to find a more reliable anticancer strategy. The incidence and mortality of gastrointestinal system tumors is extremely high. Now， more and more domestic and foreign experiments have been developed to build digestive system PDTX models and use them for the study of the corresponding tumors. This paper reviewed the latest application of PDTX model in gastrointestinal system tumor research， and the future development of tumor therapy is discussed and forecasted.