p53 polymorphism in human papillomavirus-associated Kazakh's esophageal cancer in Xinjiang,China

AIM: To investigate the relationship between p53 codon 72 polymorphism and human papillomavirus (HPV) type 16 infection in Kazakh's esophageal cancer (EC) in Xinjiang, China.METHODS: Encoding regions of p53codon 72 and HPV-16 E6 were amplified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and polymerase chain reaction (PCR) methods using pairs of primary esophageal squamous cell carcinoma (SCC) tissue and corresponding normal mucosa, which were collected from 104 patients of Kazakh in Xinjiang, China. RESULTS: Only arginine allele was detected in 70.1% (39/55) of HPV-16-E6-positive cases but only in 40.8% (20/49) of HPV-16-E6-negative cases (P<0.05; OR, 3.53; 95% CI, 1.57-7.98). In contrast, such a significant correlation between p53 polymorphism and HPV infection was not evident in corresponding normal mucosae. The allele frequency of Arg allele in cancer cases (0.68) was higher than that in normal mucosa samples (0.54) (P<0.05; OR, 1.80; 95% CI, 1.21-2.69).CONCLUSION: p53 codon 72 Arg homozygous genotype is one of the high-risk genetic factors for HPV-associated SCC of Kazakh. Individuals carrying Arg allele compared to those with Pro allele have an increased risk for esophageal SCC.

Relationship between genetic polymorphisms of metabolizing enzymes CYP2E1, GSTM1 and Kazakh's esophageal squamous cell cancer in Xinjiang, China

AIM: To analyze the relationship between genetic polymorphisms of metabolizing enzymes CYP2E1, GSTM1 andKazakh's esophageal squamous cell cancer in China.METHODS: The genotypes of cytochromes P450 (CYP) 2E1 and glutathione S-transferase (GST) M1 were investigated by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) following PCR in 104 Kazakh's patients with esophageal cancer (EC) and 104 non-cancer controls.RESULTS: The frequency of CYP2E1 c1/c1 genotype was significantly higher in patients with cancer (77.9%) thanin control subjects (24.0%) (P＜0.05; OR, 11.13; 95%CI,5.84-21.22). The difference of GSTM1 null was significantly more frequent in the cancer (34.6%) vsthe control group (3.8%) (P＜0.05; OR, 13.24; 95%CI, 4.50-38.89). On the other hand, the combination of GSTM1 presence and CYP2E1 c1/c1 genotypes increased the risk for cancer (P＜0.05;OR, 13.42; 95%CI, 6.29-28.3).CONCLUSION: The CYP2E1 c1/c1, GSTM1 deletion genotypes are genetically susceptible biomarkers for ESCC in Kazakh population. Individuals with allele c1 of RsaI polymorphic locus for CYP2E1 may increase the risk of ESCC. Moreover, CYP2E1 wild type (c1/c1) increased thesusceptibility to ESCC risk in Kazakh individuals with GSTM1 presence genotype.

Cloning and expression of ornithine decarboxylase gene from human colorectal carcinoma

AIM: To construct and express ODC recombinant gene for further exploring its potential use in early diagnosis of colorectal carcinoma.METHODS: Total RNA was extracted from colon cancer tissues and amplified by reverse-transcription PCR with two primers, which span the whole coding region of ODC. The synthesized ODC cDNA was cloned into vector pQE-30 at restriction sites BamH I and Sal I which constituted recombinant expression plasmid pQE30-ODC. The sequence of inserted fragment was confirmed by DNA sequencing,the fusion protein including 6His-tag was facilitated for purification by Ni-NTA chromatographic column.RESULTS: ODC expression vector was constructed and confirmed with restriction enzyme digestion and subsequent DNA sequencing. The DNA sequence matching on NCBI Blast showed 99 % affinity. The vector was transformed into E.coli M15 and expressed. The expressed ODC protein was verified with Western blotting.CONCLUSION: The ODC prokaryote expression vector is constructed and thus greatly facilitates to study the role of ODC in colorectal carcinoma.

Comparative proteome analysis of untreated and Helicobacter pylori-treated HepG2

AIM: To investigate the pathological effect of Helicobacter pylori (H pylori) on human hepatic cells, proteomic methods were used to find and to identify proteins that were overexpressed in HepG2 cells treated by H pylori. METHODS: H pylori was co-cultured with HepG2 for 6 h. Two-dimensional gel electrophoresis was used to gain the protein expression pattern of untreated and H pylori-treated HepG2. After staining and image analysis, spots of interest were isolated and subjected to mass spectrometry. RESULTS: Seven proteins, which were up-regulated in H pylori -treated HepG2 cells, were identified. These proteins included integrin beta-1, protein kinase C alpha, LIM/ homeobox protein Lhx1, eIF-2-beta, MAP kinase kinase 3, PINCH protein and Ras-related protein Rab-37, which involved in transcription regulation, signal transduction, metabolism and so on, CONCLUSION: H pylori may exert the pathological effect on HepG2 cells by up-regulating the expression of some proteins.

Nonlinear system PID-type multi-step predictive control

A compound neural network was constructed during the process of identification and multi-step prediction. Under the PID-type long-range predictive cost function, the control signal was calculated based on gradient algorithm. The nonlinear controller’s structure was similar to the conventional PID controller. The parameters of this controller were tuned by using a local recurrent neural network on-line. The controller has a better effect than the conventional PID controller. Simulation study shows the effectiveness and good performance.

A novel method for preparation of tissue microarray

AIM:To improve the technique of tissue microarray (tissue chip).METHODS: A new tissue microarraying method was invented with a common microscope installed with a special holing needle, a sampling needle, and a special box fixing paraffin blocks on the microscope slide carrier. With the movement of microscope tube and objective stage on vertical and cross dimensions respectively, the holing procedure on the recipient paraffin blocks and sampling procedure of core tissue biopsies taken from the donor blocks were performed with the refitted microscope on the same platform.The precise observation and localization of representative regions in the donor blocks were also performed with the microscope equipped with a stereoscope.RESULTS: Highly-qualified tissue chips of colorectal tumors were produced by a new method, which simplified the conventional microarraying procedure, and was more convenient and accurate than that employing the existing tissue microarraying instruments.CONCLUSION:Using the refitted common microscope to produce tissue microarray is a simple, reliable, cost-effective and well-applicable technique.

Ornithine decarboxylase gene is overexpressed in colorectal carcinoma

AIM: To investigate the ornithine decarboxylase (ODC)gene expression in colorectal carcinoma, ODC mRNA was assayed by RT-PCR and ODC protein was detected by a monoclonal antibody against fusion of human colon ODC prepared by hybridoma technology.METHODS: Total RNA was extracted from human colorectal cancer tissues and their normal counterpart tissues. ODC mRNA levels were examined by RT-PCR.ODC genes amplified from RT-PCR were cloned into a prokaryotic vector pQE-30. The expressed proteins were purified by chromatography. Anti-ODC mAb was prepared with classical hybridoma techniques and used to determine the ODC expression in colon cancer tissues by immunohistochemical and Western blotting assay.RESULTS: A cell line, which could steadily secrete antiODC mAb, was selected through subcloning four times.Western blotting reconfirmed the mAb and ELISA showed that its subtype was IgG2a. RT-PCR showed that the ODC mRNA level increased greatly in colon cancer tissues (P＜0.01). Immunohistochemical staining showed that colorectal carcinoma cells expressed a significantly higher level of ODC than normal colorectal mucosa (98.6±1.03%vs 5.26±5%, P＜0.01).CONCLUSION: ODC gene overexpression is significantly related to human colorectal carcinoma. ODC gene expression may be a marker for the gene diagnosis and therapy of colorectal carcinoma.

18F-FDG PET/CT in vivo assessment of correlation between vascular calcification and inflammation

Objective:To explore the relationship between calcification of human vascular system and local inflammation using PET/CT.Methods:Patients who were treated with concurrent PET/CT in our hospital were collected continuously,and their arterial image data were analyzed in parallel with standardized uptake values.(SUV)and corresponding slice calcification score(CS)measurement.SUV values were collected and measured for slices with CS greater than 100.Patients were grouped according to CS,and the correlation analysis between SUV values and CS in each group was performed.Results:Overall CS and SUVmax(r=0.62,P<0.05)and SUVmean(r=0.59,P<0.05)were positively correlated,among which CS and SUV values were in the SUVmax(r=0.72,P<0.05),SUVmean(r=0.59,P<0.05),SUVmax of CS 200-299 group(r=0.71,P<0.05),SUVmean(r=0.80,P<0.05),SUVmax of CS 300-399 group(r=0.47,P<0.05),SUVmean(r=0.53,P<0.05)were positively correlated,SUVmax(r=-0.17,P>0.05),SUVmean(r=-0.07,P>0.05)were negatively correlated in CS 400-499 group,CS There was no significant correlation between SUVmax(r=0.22,P>0.05)and SUVmean(r=0.18,P>0.05)in the 500 group.Conclusion:There is a certain correlation between the local vascular calcification area and the corresponding local inflammatory response in the calcification progress PET/CT has the potential to monitor early calcification.