Prognostic value of MET, cyclin D1 and MET gene copy number in non-small cell lung cancer

The aim of this study was to analyze the correlation of the expression of MET and cyclin D1 and MET gene copy number in non-small cell lung cancer （NSCLC） tissues and patient clinicopathologic characteristics and sur- vival. Sixty-one NSCLC tissue specimens were included in the study. The expression of MET and cyclin D1 was evaluated by immunohistochemistry and MET gene copy number was assessed by quantitative real-time polymer- ase chain reaction （Q-PCR）. Positive expression of MET and cyclin D1 protein and increased MET gene copy number occurred in 59.0%, 59.0% and 18.0% of 61 NSCLC tissues, respectively. MET-positivity correlated with poor differentiation （P = 0.009）. Increased MET gene copy number was significantly associated with lymph node metastasis （P = 0.004） and advanced tumor stage （P = 0.048）, while the expression of cyclin D1 was not associ- ated with any clinicopathologic parameters. There was a significant correlation between the expression of MET and MET gene copy number （P = 0.002）. Additionally, the expression of cyclin D1 had a significant association with the expression of MET as well as MET gene copy number （P = 0.002 and P = 0.017, respectively）. MET- positivity and increased MET gene copy number were significantly associated with poor overall survival （P = 0.003 and P 〈 0.001, respectively） in univariate analysis. Multivariate Cox proportional hazard analysis confirmed that the expression of MET and MET gene copy number were prognostic indicators of NSCLC （P = 0.003 and P = 0.001, respectively）. The overexpression of MET and the increased MET gene copy number might be adverse prognostic factors for NSCLC patients. The activation of the MET/cyclin D1 signaling pathway may contribute to carcino- genesis and the development of NSCLC, and may represent a target for therapy.

EGFR gene copy number as a predictive biomarker for resistance to anti-EGFR monoclonal antibodies in metastatic colorectal cancer treatment:a meta-analysis

Objective：The epidermal growth factor receptor （EGFR） inhibitors monoclonal antibodies （MoAbs） have already shown the therapeutic effectiveness in patients with metastatic colorectal cancer （mCRC）.But many patients resist to the treatment.The aim of this meta-analysis was to assess EGFR gene copy number （GCN） as a candidate predictive biomarker for resistance to anti-EGFR MoAbs in mCRC treatment.Methods：Systematic computerized searches of the PubMed,EMBase and Cochrane Library were performed.The primary endpoint was objective response rate （ORR）.The second endpoints included progression-free survival （PFS）,and overall survival （OS）.The pooled odd ratio （OR） and pooled sensitivity,specificity,and summary receiver operator characteristic （SROC） for ORR were estimated.The pooled hazard ratios （HR） for PFS and OS were also calculated.Results：Fourteen studies with 1,021 patients were included.Increased EGFR GCN was associated with increased ORR （OR=6.905; 95％ CI：4.489-10.620）.It was also found in wild-type KRAS mCRC patients,with the pooled OR of 8.133 （95 ％ CI：4.316-15.326）.GCN has medium value for predicting ORR,with the pooled sensitivity of 0.79 （95％ CI：0.73-0.84）,the pooled specificity of 0.59 （95％ CI：0.55-0.62）.In wildtype KRAS mCRC patients,the sensitivity and the specificity were 0.80 （95％ CI：0.70-0.87） and 0.60 （95％CI：0.53-0.66）,respectively.Increased EGFR GCN was associated with increased PFS （HR=0.557; 95％ CI：0.382-0.732） and OS （HR=0.579; 95％ CI：0.422-0.737）.Conclusions：This meta-analysis suggests that EGFR GCN represents a predictive biomarker for tumor response in mCRC patients treated with MoAbs regardless of KRAS mutation.mCRC patients with increased EGFR GCN are more likely to have a better response,PFS,and OS when treated with cetuximab or panitumumab.

Determining the Copy Number of Exogenous Gene in Transgenic Plant by SYBR Green Real-time Quantitative PCR

[Objective] To explore the feasibility of using SYBR Green real-time quantitative PCR technique to estimate the copy numbers of exogenous gene in a transgenic plant.[Methods] Using SYBR Green real-time quantitative PCR technique,we have determined the copy numbers of the exogenous CYCD3;1 in transgenic Arabidopsis by comparing an endogenous single copy reference gene with CYCD3;1 copy numbers in transgenic plant,meanwhile comparing CYCD3;1 copy numbers between wild plant and transgenic plant.[Results]The exogenous CYCD3;1 copy numbers calculated by this method is identical with results of traditional Southern blot analysis which is highly accurate.[Conclusion]This method is simple,effective and safe for estimating transgene copy numbers.

Amplifi cations of NCOA3 gene in colorectal cancers in a Chinese population

AIM: To investigate the copy number variation of NACO3 gene in colorectal cancer (CRC) and its correlation with tumor progression. METHODS: A total of 142 samples of case-matched CRC tissues and adjacent normal tissues were obtained from patients undergoing bowel resection. Quantitative real-time polymerase chain reaction method was used to investigate the copy number variations of NCOA3 as well as gene expression in the collected tissues. RESULTS: Copy number gains of NCOA3 were detected in 39 CRC samples (27.5%) and were correlatedwith tumor progression (χ2 = 6.42, P = 0.0112). Moreover, there was a positive correlation between copy number gain and mRNA over-expression of NCOA3 in CRCs (P = 0.0023). Expression level of NCOA3 mRNA was also enhanced in the CRC samples with unaltered copy numbers (3.85 ± 1.23 vs 2.71 ± 0.64, P < 0.01). CONCLUSION: Sporadic colorectal cancers exhibit different mechanisms of NCOA3 regulation.

Combinatorial Effects of SDF-1 and CCL3L1 Gene Variants and Susceptibility to HIV-1/AIDS in Indian Population

HIV-1 infection requires the expression of CD4＋ molecules in colligation with C-C chemokine receptor type 5 （CCR5） and C-X-C chemokine receptor type 4 （CXCR4） as the major coreceptors. The role of SNP in 3＇ untranslated region ofSDF-1 （SDF1-3 ＇A） and low copy number （CN） of the CCL3L1 gene is reported to confer increased resistance to HIV-1 infection. The aim of the present study was to analyze the combinatorial effect of both the variations in protection towards HIV-1 infection in Indian population. The combinatorial effect of genetic variation in terms of SNP in SDF-1 gene and CCL3L1 CN was investigated in 105 healthy individuals and 78 HIV-I patients. Genotyping of SDF-1 was performed by RFLP-PCR and CCL3L1 by real-time PCR using TaqMan chemistry. The genotype frequency distribution of SDF-1 was found to be （SDF-1/SDF-I： 65.4%, SDF-1/SDF1-3＇A： 29.5% and SDFI-3＇A/SDF1-3＇A- 5.1%） in HIV patients as compared to （SDF-1/SDF-I： 64.8%, SDF-1/SDF1-3＇A： 30.5% and SDF1-3 ＇A/SDF1-3 ＇A： 4.7%） in healthy individuals, whereas a range of 1 to 6 copies per diploid genome was observed for CCL3L1 gene.

Target Resistance of Eleusine indica to Glyphosate

[Objectives]This study was conducted to detect the evolution of resistance to glyphosate in Eleusine indica.[Methods]In the previous study,glyphosate-resistant population T2-4 was screened out from E.indica populations in sugarcane fields in Guangxi.In this study,we determined the resistance index of T2-4 by whole plant bioactivity assay and further explored the molecular biological mechanism of resistance.[Results]The resistance index of T2-4 was 112,and it is thus a highly resistant population.Amino acid mutations were found at positions 102,106 and 381 in the EPSPS sequence of T2-4,containing at least a triple mutation allele in Thr-102-Ile,Pro-106-Ser and Pro-381-Leu and a double mutation allele in Pro-106-Ser and Pro-381-Leu.qPCR was used to determine the EPSPS gene copy number and expression in resistant plants of T2-4.EPSPS gene copy number and expression both increased,with 8.3-fold higher copy number and 2.7-fold higher expression than the sensitive population.Therefore,the resistance of T2-4 to glyphosate was mainly caused by multiple target mechanisms including mutation of EPSPS gene,copy number increase and expression increase,and the resistance of E.indica to glyphosate needs our high attention.[Conclusions]At present,the level of resistance to glyphosate is very high in the sugarcane fields of Guangxi,and it is necessary to take a variety of weed control measures to solve the problem of glyphosate resistance.