Objective To explore the effects of DNA cross-linking repair 1B (DCLRE1B) gene on the migration and invasion ability of hepatocellular carcinoma cell. Methods Bioinformatics analysis was used to analyze the expression of DCLRE1B mRNA in hepatocellular carcinoma, and its relationship with the prognosis and related influencing factors of patients. Immunohistochemical staining was used to detect the expression of DCLRE1B protein in resected hepatocellular carcinoma tissues and their corresponding normal liver tissues. The DCLRE1B gene silenced Huh7 and HepG2 hepatocellular carcinoma cell lines were constructed by lentivirus, and the transfected effect was detected by Western blot. The migration and invasion of DCLRE1B silenced hepatocellular carcinoma cells were detected by scratch test and Transwell method. The changes of genes related to epithelial mesenchymal transformation (EMT) after DCLRE1B silencing were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Results ① The biological information analysis results showed that: The mRNA expression of DCLRE1B was highly expressed in a variety of tumors including hepatocellular carcinoma (P<0.05). The mRNA expression of DCLRE1B was associated with the TNM staging of tumor (P<0.05). The relative expression level of DCLRE1B mRNA in hepatocellular carcinoma patients was related to their prognosis. The overall survival situation (P=0.038) and progression free survival situation (P=0.005) of hepatocellular carcinoma patients in the high expression group were worse than those in the low expression group. Univariate and multivariate Cox analysis showed that the expression of DCLRE1B gene was an independent factor affecting the prognosis of hepatocellular carcinoma (P<0.05). ② The positive rate of DCLRE1B protein expression in resected hepatocellular carcinoma tissues was higher than that in normal liver tissues (P<0.05). ③ Cell experiment results showed that: After stable silencing DCLRE1B gene of hepatocellular carcinoma cell (Huh7 and HepG2) constructed by lentivirus, the expression of DCLRE1B protein was significantly down regulated (P<0.05). After silencing DCLRE1B gene, the migration and invasion ability of hepatocellular carcinoma cells were significantly decreased (P<0.05). After silencing DCLRE1B, the mRNA expressions of E-cadherin, matrix metalloproteinase 9, and β-catenin were up regulated (P<0.05), and the mRNA expressions of N-cadherin and Vimentin were down regulated (P<0.05), but the mRNA expression of zinc finger transcription factor had no significant change, and the difference was not statistically significant (P＞0.05). Conclusion Silencing DCLRE1B gene can inhibit the migration and invasion ability of hepatocellular carcinoma cells, and its mechanism may be related to the process of EMT.
Objective To investigate the effects of DNA methyltransferase inhibitor (DNMTi) and histone deacetylase inhibitor (HDCAi) on expression of E-cadherin gene and invasiveness of cholangiocarcinoma cell. Methods According to different treatment, the QBC939 cells were divided into four groups: blank control group, hydralazine group, valproic acid group and hydralazine and valproic acid combined group. After 48 h, the expression of E-cadherin was evaluated by reverse transcription-PCR (RT-PCR), mehtylation specific PCR (MSP) and Western blot, the invasiveness of QBC939 cells was evaluated by Transwell method. Results There was no expression of E-cadherin mRNA and protien in blank control group and valproic acid group. The expressions of E-cadherin mRNA and protien in hydralazine and valproic acid combined group were higher than those in hydralazine group ( P ＜ 0.01), while the invasiveness of QBC939 cells of hydralazine and valproic acid combined group was much lower than that of blank control group, hydralazine group and valproic acid group ( P ＜ 0.01). Conclusion DNMTi and HDACi can synergistically re-express E-cadherin gene and weaken the invasiveness of QBC939 cell, which plays an important part in treatment of cholangiocarcinoma.
Objective To investigate the spectrum of mitochondrial DNA (mtDNA) mutations in Chinese patients with Leber′s hereditary optic neuropathy (LHON). Methods The primary mtDNA mutations (G3460A、G11778A and T14484 C) of 140 patients with LHON were detected by mutation-specific priming polymerase chain reaction (MSP-PCR), heteroduplex-single strand conformation polymorphism polymerase chain reaction (HA-SSCP), restriction fragment length polymorphisms (RFLP) and measurement of DNA sequence. The transmissibility of the patients′ stirps was analyzed.Results In the 140 patients with LHON, G11778A mtDNA primary mutation was found in 130 (92.9%), including 113 males and 17 females; G3460A mutation was found in 2 (1.4%) including 1 male and 1 female; G14484A mutation was found in 8 (5.7% ) including 6 males and 2 females.Conclusion In Chinese patients with LHON, the incidence of G11778A mtDNA mutation is higher than that of G3460A and T14484C. (Chin J Ocul Fundus Dis，2003，19：269-332)
Leber hereditary optic neuropathy (LHON) is a blinding disease caused by mutations in mitochondrial DNA. It is a classic disease model for studying mitochondrial abnormalities. Its main mutation sites are m11778G.A, m.3460G.A and m.14484T.C. LHON cell models are mainly produced by lymphoblasts, fibroblasts, cell hybrids and induced pluripotent stem cells, while LHON animal models are mainly mice, which are produced by rotenone and ND4 mutants. Although the research on the LHON model has achieved good results, there are still many difficulties in constructing an ideal experimental model, which severely limit the exploring to the pathogenesis and therapeutic drugs of LHON. A detailed understanding of the application and characteristics of existing models in LHON will help improve experimental design and construct new models.
Objective To systematically review the correlation between polymorphism of DNA methyltransferase 1(DNMT1) rs16999593 and the susceptibility of breast cancer. Methods Databases such as PubMed, EMbase, Web of Science, Chinese Biomedical Literature Database, CNKI, WanFang, and VIP database were searched from inception to Mar. 2017 to collect case-control studies on the correlation between DNMT1 rs16999593 C/T polymorphism and the susceptibility of breast cancer. Two reviewers independently identified the literatures according to inclusion and exclusion criterias, extracted data, and assessed the quality of the included studies. The meta-analysis was performed by using RevMan 5.3 software. Results A total of 5 studies involving 1 741 cases and 1 917 control subjects were included. The results of meta-analysis showed that, dominate model ［TT+TC vs. CC: OR=0.63, 95% CI was (0.30, 1.30), P=0.21］, homozygous model ［TT vs. CC: OR=1.01, 95% CI was (0.70, 1.47), P=0.95］, heterozygous model ［TC vs. CC: OR=0.44, 95% CI was (0.18, 1.04), P=0.06］, and additive model ［T vs. C: OR=1.29, 95% CI was (0.90, 1.86), P=0.16］ were not significantly related to breast cancer, but recessive gene model was related to breast cancer ［TT vs. TC+CC: OR=1.74, 95% CI was (1.01, 3.00), P=0.04］. Conclusion The current studies showed that, DNMT1 rs16999593 TT genotype decreases the susceptibility of breast cancer.
Objective To evaluate the prognostic and pathobiologic significance of DNA content. Methods DNA content was conducted on 140 hepatocellular carcinoma patients by flow cytometry. Cancer recurrence was followed up after the patients were discharged. The statistical software used was SPSS. Results DNA ploidy did not correlate with clinicobiologic features, except with the age of the patients (Ｐ＜0.05), tumor size and AFP level (Ｐ＜0.01). The mean following up time of the patients with diploid was 31.2 months. The recurrence rate was 23.1%. In aneuploid group the mean following up time was 22.6 months. The recurrence rate was 50.0%. Ploidy correlated significantly with recurrence rate, the recurrence rate for patients with aneuploid were significantly higher than for those of diploid (Ｐ=0.013), also the recurrence rate of aneuploid within one year (37.9%) was much higher than that of diploid (4.3%) Ｐ=0.002. In a Logistic multivariate analysis of DNA content, the grade of cirrhosis severity and the tumor size were considered to be independent factors that related with recurrence. Conclusion FCM DNA analysis of radically resected HCC is a simple and valid method to predict the recurrence.
Objective To analyze the relationship between genotype and phenotype of vitelline macular dystrophia (VMD2) gene in a family with Best disease, and to provide the theoretical basis for gene diagnosis of Best disease. Methods Mutation in the coding regions and the promotor sequence of VMD2 gene from 10 members in a family with Best disease were screened by polymerase chain reaction (PCR) and direct DNA sequencing, and combined with a conformation sensitive gel electrophoresis (CSGE) approach, VMD2 gene screening was performed on 100 normal control individuals. Results In the 10 members, Trarr;C nucleotide change at the 223 base of exon 3 was detected in 9, including 6 with Best disease who was confirmed by ophthalmoscopy and electrophysiological examination in whom 2 were affirmed as having homozygote of this mutation. Other 3 young family members with VMD2 gene mutation only had abnormal electro-oculogram manifestations. Above mutation was not detected in the normal control individuals. Conclusions The phenotype and genotype of VMD2 in the family with Best disease is highly correlated. Mutation in VMD2 gene is the nosogenesis in this family. Mutation screening of VMD2 gene can be used for genic diagnosis and genetic consultation of Best disease. (Chin J Ocul Fundus Dis, 2006, 22: 86-89)
This study aims to explore the temporal pattern of DNA breaks induced by nanosecond electric pulses (nsEP) in cisplatin-sensitive and cisplatin-resistant human ovarian cancer cells. Human ovarian cancer cells A2780 (cisplatin-sensitive subline) and C30 (cisplatin-resistant subline) were exposed to nsEP. Sham exposed groups were shame exposed to nsEP. Cell viability was determined using CCK-8 assay after 0 h, 4 h, 8 h, 12 h and 24 h, respectively, and the percentage of dead cells was calculated. The DNA break was detected with the alkaline single cell gel electrophoresis (comet assay), and the 75th percentiles of TL (tail length), TM (tail moment) and OTM (Olive tail moment) were measured. Cell viability displayed an early decrease and late increase, with the valley value seen at 8 h. Percentages of cell death and comet-formed in A2780 cells were higher than those in C30 cells (P<0.05) at 8 h, respectively. TL, TM and OTM in C30 cells were less than those in A2780 cells (P<0.05). The percentage of comet-formed correlated with that of cell death in either A2780 (r=0.997, P<0.05) or C30 (r=0.998, P<0.05) cells. DNA breaks induced by nsEP in cisplatin-sensitive cells differred from that in resistant cells, and DNA break resulted in fraction of cell death.
Objective To analyze the clinical characteristics and to screen for causative mutations in CRX and GUCY2D genes in children with cone or cone-rod dystrophy. Methods Clinical data and genomic DNA was collected from 18 children with cone or cone-rod dystrophy, aged from 4 months to 8 years. The coding sequence of the cone-rod homeobox (CRX) gene and two exons of the retinal-specific guanylate cyclase GUCY2D gene (exons 2 and 8) were analyzed by using polymerase chain reaction(PCR) and heteroduplex combined with single-strand conformational polymorphism (heteroduplex-SSCP) analysis. Results All of the 18 patients manifested obvious visual impairment. Nystagmus, photophobia and mild ocular fundus changes were found in 13, 8,and 7 cases respectively. Normal fundus was seen in 11 cases. The visual acuity was less than 0.3 in 4 cases and was unable to measure in the other 14 cases because they were too young. Clinical ocular manifestation s between cone and cone-rod dystrophy were overlapped. Mutation in the CRX and G UCY2D genes was not detected in the 18 children with cone and cone-rod dystrophy . Conclusion Visual impairment appeared more early and obvious than fundus changes in children with cone or cone-rod dystrophy. Mutation in the CRX gene may not contribute to this series of patients with cone and cone-rod dystrophy. (Chin J Ocul Fundus Dis, 2001,17:293-295)
Objective To investigate the genetic polymorphism of methicillin resistant Staphylococcus aureus ( MRSA) isolated from hospital acquired pneumonia. Methods Seventy-four hospitalized patients were diagnosed as noscomial MRSA pneumonia from January 2007 to January 2008 in Xinhua Hospital, Shanghai Jiaotong Univesity. The genes of MRSA were amplified by random amplified polymorphic DNA typing ( RAPD) assay in 82 clinical isolates from these patients. Results Two to 15 amplified DNA fragments were observed in agarose gel and they were classified into 11 genotypes. Genotypes Ⅲ, Ⅵ and Ⅶ ( 32. 56% , 30. 23% and 13. 95% , respectively) were mainly isolated from the ICU. Both independent genotypes and overlapping genotpyes with those from ICU were identified in isolates from the departments of geriatrics, emergency and respiratory medicine. Outbreak or cluster cases ( 48. 65% ) were found in 36 of the 74 patients while all outbreak cases occurred in the ICU. Conclusions Noscomial MRSA pneumonia is easy to disseminate and small-scale outbreak may occur especially in ICU. RAPD is valuable for identification and prevention of the spread of MRSA in hospital.