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1.
Chinese Medical Journal ; (24): 939-944, 2018.
Article in English | WPRIM | ID: wpr-687005

ABSTRACT

<p><b>Background</b>Promoter methylation of MGMT and C13ORF18 has been confirmed as a potential biomarker for early diagnosis of cervical cancer. The aim of this study was to evaluate the performance of MGMT and C13ORF18 promoter methylation for triage of cytology screening samples and explore the potential mechanism.</p><p><b>Methods</b>Methylation-sensitive high-resolution melting was used to detect promoter methylation of MGMT and C13ORF18 in 124 cervical samples. High-risk human papillomavirus (HR-HPV) was detected by the Digene Hybrid Capture 2. Gene methylation frequencies in relation to cervical intraepithelial neoplasia (CIN) were analyzed. Frequencies were compared by Chi-square tests. The expression of gene biomarkers and methylation regulators was analyzed by immunohistochemical staining, real-time fluorescence quantitative polymerase chain reaction, and Western blot.</p><p><b>Results</b>For triage of low-grade squamous intraepithelial lesion (LSIL), gene methylation increased specificity from 4.0% of HR-HPV detection to 30.8% of MGMT (χ = 9.873, P = 0.002) and to 50.0% of C13ORF18 (χ = 21.814, P = 0.001). For triage of atypical squamous cells of undetermined significance, HR-HPV detection had higher positive predictive value of 54.8%. Either MGMT or C13ORF18 methylation combined with HR-HPV increased the negative predictive value to 100.0% (χ = 9.757, P = 0.002). There was no relationship between MGMT and C13ORF18 expression and DNA methylation (χ = 0.776, P = 0.379 and χ = 1.411, P = 0.235, respectively). MBD2 protein level in cervical cancer was relatively lower than normal cervical tissue (t = 4.11, P = 0.006).</p><p><b>Conclusions</b>HR-HPV detection is the cornerstone for triage setting of CIN. Promoter methylation of MGMT and C13ORF18 plays a limited role in triage of LSIL. Promoter methylation of both genes may not be the causes of gene silence.</p>


Subject(s)
Adult , Cervical Intraepithelial Neoplasia , Genetics , Pathology , Chi-Square Distribution , DNA Methylation , Genetics , DNA Modification Methylases , Genetics , DNA Repair Enzymes , Genetics , Female , Humans , Middle Aged , Promoter Regions, Genetic , Genetics , Squamous Intraepithelial Lesions of the Cervix , Genetics , Pathology , Tumor Suppressor Proteins , Genetics , Uterine Cervical Neoplasms , Genetics , Pathology , Young Adult
2.
Chinese Journal of Pediatrics ; (12): 56-60, 2016.
Article in Chinese | WPRIM | ID: wpr-351449

ABSTRACT

<p><b>OBJECTIVE</b>Cockayne syndrome is a rare disease and difficult to be recognized. This study aimed to expand the knowledge of the clinical and molecular characteristics of the children with Cockayne syndrome (CS).</p><p><b>METHOD</b>Clinical data of two siblings with classic CS of Guangzhou Women and Children's Medical Center from July 2013 to November 2014 were obtained and analyzed. The whole DNA of peripheral blood was collected from two CS siblings and their parents. Amplification of all exons and adjacent introns for ERCC6 gene was conducted using PCR, and measurement of reaction product was performed to find mutation sites by two-way sequencing.</p><p><b>RESULT</b>Two affected siblings were males, and came from unconsanguineous parents, 7 years and 5 months old and 4 years and 8 months old, respectively. They were in treatment because of developmental and mental retardation for years. When they were younger than one year of age, their heights and weight were within normal limits. However, poor growth of height and weight and psychomotor retardation appeared after one and a half years of age, as well as skin and eye sensitivity to sunshine, hearing impairment, optic nerve atrophy, microcephaly, and deep-set eyes. The proband's height was 90.8 cm, and weight 9.1 kg, head circumference 41 cm, and chest circumference 44 cm when he was taken to hospital. The elder brother of the proband had a height of 92 cm, weight 11.2 kg, head circumference 41 cm, and chest circumference 44 cm when he was taken to hospital. When the proband was four and a half years old, ventricular enlargement, hypomyelination, and brain atrophy were detected for his elder brother at 7 years of age by cranial MRI. MRS imaging indicated that damages occurred at the left and right sides of dorsal thalamus, lobus insularis, along with the left half circle of central neurons. Symmetrical calcification on bilateral basal ganglia was found on the brain CT scan. Pathogenic compound heterozygous c. 1357C > T (p.Arg453Ter) and c. 1607T > G (p.Leu536Trp) mutations of ERCC6 gene were identified in the two siblings which were separately inherited from their unaffected parents.</p><p><b>CONCLUSION</b>CS children are usually normal at birth, however, they have severe clinical characteristics such as poor growth, psychomotor retardation, cerebral injury, microcephalus, deep-set eyes, and skin sensitivity to sunshine. ERCC6 gene mutation usually occurs, and it is easy to misdiagnose CS as cerebral palsy, primary microcephaly, and so on.</p>


Subject(s)
Asians , Child , Child, Preschool , Cockayne Syndrome , Genetics , DNA Helicases , Genetics , DNA Mutational Analysis , DNA Repair Enzymes , Genetics , Exons , Heterozygote , Humans , Magnetic Resonance Imaging , Male , Mutation , Poly-ADP-Ribose Binding Proteins , Polymerase Chain Reaction , Siblings
3.
Article in English | WPRIM | ID: wpr-27943

ABSTRACT

OBJECTIVE: Recent investigations have revealed DNA mismatch repair (MMR) gene mutations are closely related with carcinogenesis of endometrial cancer; however the impact of MMR protein expression on prognosis is not determined. Correlations between MMR-related protein expression and clinicopathological factors of endometrial cancers are analyzed in the present study. METHODS: A total of 191 endometrial cancer tissues treated between 1990 and 2007 in our hospital were enrolled. Immunoreactions for MSH2, MLH1, MSH6, and PMS2 on tissue microarray specimens and clinicopathological features were analyzed retrospectively. RESULTS: Seventy-six cases (40%) had at least one immunohistochemical alteration in MMR proteins (MMR-deficient group). There were statistically significant differences of histology, International Federation of Gynecology and Obstetrics (FIGO) stage, and histological grade between MMR-deficient group and the other cases (MMR-retained group). Response rate of first-line chemotherapy in evaluable cases was slightly higher in MMR-deficient cases (67% vs. 44%, p=0.34). MMR-deficient cases had significantly better progression-free and overall survival (OS) compared with MMR-retained cases. Multivariate analysis revealed MMR status was an independent prognostic factor for OS in endometrial cancers. CONCLUSION: MMR-related proteins expression was identified as an independent prognostic factor for OS, suggesting that MMR was a key biomarker for further investigations of endometrial cancers.


Subject(s)
Adaptor Proteins, Signal Transducing/deficiency , Adenosine Triphosphatases/deficiency , Adult , Aged , Aged, 80 and over , Chemotherapy, Adjuvant , DNA Mismatch Repair , DNA Repair Enzymes/deficiency , DNA-Binding Proteins/deficiency , Endometrial Neoplasms/diagnosis , Female , Humans , Kaplan-Meier Estimate , Middle Aged , MutS Homolog 2 Protein/deficiency , Neoplasm Proteins/deficiency , Nuclear Proteins/deficiency , Prognosis , Retrospective Studies , Biomarkers, Tumor/metabolism
4.
Article in Chinese | WPRIM | ID: wpr-346125

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the association between single nucleotide polymorphism (SNP) (rs17166050) in RAD50 gene and acute lymphoid leukemia (ALL) in children.</p><p><b>METHODS</b>A total of 177 ALL children from Wuhan and surrounding areas and 232 healthy children were selected. The numbers of standard-risk, medium-risk, and high-risk children were 66, 69, and 42, respectively. The genotypes of SNP in RAD50 gene were determined using PCR-RFLP, and the relationship of the RAD50 polymorphism with ALL susceptibility and clinical risk was analyzed.</p><p><b>RESULTS</b>The genotype (AA, GA, and GG) distribution of SNP in RAD50 gene showed significant differences between the ALL and control groups (P=0.038), and G allele was significantly associated with ALL susceptibility (OR=1.459, 95% CI: 1.034-2.057, P=0.031). However, the SNP was not associated with the risk stratification of ALL.</p><p><b>CONCLUSIONS</b>The SNP (rs17166050) in RAD50 gene is associated with the susceptibility to ALL in children, but is not associated with the risk stratification of ALL.</p>


Subject(s)
Child , Child, Preschool , DNA Repair Enzymes , Genetics , DNA-Binding Proteins , Genetics , Female , Genetic Predisposition to Disease , Humans , Infant , Male , Polymorphism, Single Nucleotide , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Genetics , Risk
5.
Chinese Journal of Oncology ; (12): 591-596, 2015.
Article in Chinese | WPRIM | ID: wpr-286775

ABSTRACT

<p><b>OBJECTIVE</b>To explore the relationship between DNA mismatch repair (MMR) and clinicopathologic features and prognosis in patients with stages II and III colon cancers.</p><p><b>METHODS</b>The clinical and pathological data of 440 patients with stage II/III colon cancer after radical resection were retrospectively reviewed and analyzed. Immunohistochemical staining was used to assess the expression of MMR proteins (MLH1, MSH2, MSH6 and PMS2), and the correlation between DNA MMR and clinicopathological features and prognosis of colon cancers was analyzed.</p><p><b>RESULTS</b>Of the 440 tumor samples tested for DNA mismatch repair status, 90 (20.5%) demonstrated defective DNA mismatch repair and 350 (79.5%) had proficient DNA mismatch repair. Defective DNA mismatch repair (dMMR) was associated with young patients (≤ 60), proximal colon cancer, stage II, poorly differentiated adenocarcinoma and mucinous adenocarcinoma (P<0.05 for all). Among the 440 patients, 126 (28.6%) cases had recurrence or metastasis and 93 (21.1%) died during the median follow-up of 61.0 months. The five-year disease-free survival (DFS) rate was 82.2% among the patients with tumor exhibiting dMMR, significantly higher than that in patients with tumors exhibiting pMMR (68.9%, P=0.02). The univariate and mutlivariate analyses showed that the MMR status is an independent factor affecting 5-year disease-free survival and overall survival (OS) in colon cancer patients (P<0.05 for both).</p><p><b>CONCLUSIONS</b>Defective DNA mismatch repair (dMMR) is associated with patients with proximal colon cancer, stage II and poorly defferentiated adenocarcinoma and mucinous adenocarcinoma. The prognosis for patients with dMMR is better than those with pMMR. dMMR may be a useful biomarker for the prognosis of colon cancer.</p>


Subject(s)
Adaptor Proteins, Signal Transducing , Metabolism , Adenocarcinoma , Genetics , Metabolism , Mortality , Pathology , Adenocarcinoma, Mucinous , Genetics , Metabolism , Mortality , Pathology , Adenosine Triphosphatases , Metabolism , Age Factors , Analysis of Variance , Colonic Neoplasms , Genetics , Metabolism , Mortality , Pathology , DNA Mismatch Repair , DNA Repair Enzymes , Metabolism , DNA-Binding Proteins , Metabolism , Disease-Free Survival , Humans , Mismatch Repair Endonuclease PMS2 , MutL Protein Homolog 1 , MutS Homolog 2 Protein , Metabolism , Neoplasm Recurrence, Local , Nuclear Proteins , Metabolism , Prognosis , Retrospective Studies , Survival Rate
6.
Article in English | IMSEAR | ID: sea-157088

ABSTRACT

Background & objectives: Epigenetic alterations, in addition to multiple gene abnormalities, are involved in the genesis and progression of human cancers. Aberrant methylation of CpG islands within promoter regions is associated with transcriptional inactivation of various tumour suppressor genes. O6-methyguanine-DNA methyltransferase (MGMT) is a DNA repair gene that removes mutagenic and cytotoxic adducts from the O6-position of guanine induced by alkylating agents. MGMT promoter hypermethylation and reduced expression has been found in some primary human carcinomas. We studied DNA methylation of CpG islands of the MGMT gene and its relation with MGMT protein expression in human epithelial ovarian carcinoma. Methods: A total of 88 epithelial ovarian cancer (EOC) tissue samples, 14 low malignant potential (LMP) tumours and 20 benign ovarian tissue samples were analysed for MGMT promoter methylation by nested methylation-specific polymerase chain reaction (MSP) after bisulphite modification of DNA. A subset of 64 EOC samples, 10 LMP and benign tumours and five normal ovarian tissue samples were analysed for protein expression by immunohistochemistry. Results: The methylation frequencies of the MGMT gene promoter were found to be 29.5, 28.6 and 20 per cent for EOC samples, LMP tumours and benign cases, respectively. Positive protein expression was observed in 93.8 per cent of EOC and 100 per cent in LMP, benign tumours and normal ovarian tissue samples. Promoter hypermethylation with loss of protein expression was seen only in one case of EOC. Interpretation & conclusions: Our results suggest that MGMT promoter hypermethylation does not always reflect gene expression.


Subject(s)
Adult , Aged , DNA Methylation/genetics , DNA Modification Methylases/biosynthesis , DNA Modification Methylases/genetics , DNA Repair Enzymes/biosynthesis , DNA Repair Enzymes/genetics , Female , Gene Expression Regulation, Neoplastic , Humans , Middle Aged , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , Ovarian Neoplasms/genetics , Promoter Regions, Genetic , Tumor Suppressor Proteins/biosynthesis , Tumor Suppressor Proteins/genetics
7.
Chinese Journal of Biotechnology ; (12): 1669-1678, 2014.
Article in Chinese | WPRIM | ID: wpr-345556

ABSTRACT

Radiation sensitive protein 23 (RAD23) is a nucleotide excision repair (NER) protein that plays an important role in Ubiquitin-proteasome pathway (UPP). Schistosoma japonicum radiation sensitive protein23 (SjRAD23) cDNA sequences were amplified by PCR and cloned into pET28a (+) vector to construct recombinant expression plasmid pET28a(+)-SjRAD23. The recombinant protein was expressed as both inclusion bodies and the supernatant in Escherichia coli BL21 (DE3) cell. Immunofluorescence observation shows that SjRAD23 was mainly distributed on the tegument surface of the worms. ELISA assay reveals that specific IgG, IgG1 and IgG2a antibodies could be detected in the sera of rSjRAD23 immunized mice. Western blotting analysis shows that the recombinant SjRAD23 could be recognized by serum specific to soluble adult worm antigen of S. japonicum. BALB/c mice vaccinated with rSjRAD23 combined with 206 adjuvant revealed 35.94% worm reduction and 40.59% liver egg reduction when compared with that of the adjuvant control


Subject(s)
Animals , Antibodies, Helminth , Blood , Blotting, Western , Cloning, Molecular , DNA Repair Enzymes , Genetics , Metabolism , DNA, Complementary , Enzyme-Linked Immunosorbent Assay , Escherichia coli , Genetic Vectors , Helminth Proteins , Genetics , Allergy and Immunology , Immunoglobulin G , Blood , Mice , Mice, Inbred BALB C , Recombinant Proteins , Genetics , Allergy and Immunology , Schistosoma japonicum , Genetics , Metabolism , Schistosomiasis japonica , Vaccines , Allergy and Immunology
8.
Chinese Journal of Cancer ; (12): 4-7, 2014.
Article in English | WPRIM | ID: wpr-320543

ABSTRACT

The current World Health Organization classification system of primary brain tumors is solely based on morphologic criteria. However, there is accumulating evidence that tumors with similar histology have distinct molecular signatures that significantly impact treatment response and survival. Recent practice-changing clinical trials have defined a role for routine assessment of O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation in glioblastoma patients, especially in the elderly, and 1p and 19q codeletions in patients with anaplastic glial tumors. Recently discovered molecular alterations including mutations in IDH-1/2, epidermal growth factor receptor (EGFR), and BRAF also have the potential to become targets for future drug development. This article aims to summarize current knowledge on the molecular biology of high-grade gliomas relevant to daily practice.


Subject(s)
Aged , Brain Neoplasms , Genetics , Metabolism , Pathology , Chromosome Deletion , DNA Methylation , DNA Modification Methylases , Genetics , Metabolism , DNA Repair Enzymes , Genetics , Metabolism , Glioblastoma , Genetics , Metabolism , Pathology , Glioma , Genetics , Metabolism , Pathology , Humans , Isocitrate Dehydrogenase , Genetics , Metabolism , Neoplasm Grading , Oligodendroglioma , Genetics , Metabolism , Pathology , Point Mutation , Promoter Regions, Genetic , ErbB Receptors , Metabolism , Tumor Suppressor Proteins , Genetics , Metabolism
9.
Chinese Journal of Cancer ; (12): 25-31, 2014.
Article in English | WPRIM | ID: wpr-320542

ABSTRACT

Postoperative external beam radiotherapy was considered the standard adjuvant treatment for patients with glioblastoma multiforme until the advent of using the drug temozolomide (TMZ) in addition to radiotherapy. High-dose volume should be focal, minimizing whole brain irradiation. Modern imaging, using several magnetic resonance sequences, has improved the planning target volume definition. The total dose delivered should be in the range of 60 Gy in fraction sizes of 1.8-2.0 Gy. Currently, TMZ concomitant and adjuvant to radiotherapy has become the standard of care for glioblastoma multiforme patients. Radiotherapy dose-intensification and radiosensitizer approaches have not improved the outcome. In spite of the lack of high quality evidence, stereotactic radiotherapy can be considered for a selected group of patients. For elderly patients, data suggest that the same survival benefit can be achieved with similar morbidity using a shorter course of radiotherapy (hypofractionation). Elderly patients with tumors that exhibit methylation of the O-6-methylguanine-DNA methyltransferase promoter can benefit from TMZ alone.


Subject(s)
Aged , Antineoplastic Agents, Alkylating , Therapeutic Uses , Brain Neoplasms , Genetics , Metabolism , Therapeutics , Chemoradiotherapy , DNA Methylation , DNA Modification Methylases , Genetics , Metabolism , DNA Repair Enzymes , Genetics , Metabolism , Dacarbazine , Therapeutic Uses , Dose Fractionation, Radiation , Glioblastoma , Genetics , Metabolism , Therapeutics , Humans , Radiosurgery , Tumor Suppressor Proteins , Genetics , Metabolism
10.
Article in Chinese | WPRIM | ID: wpr-298946

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the potential substitution effect of hOGG1 and hMTH1 on oxidative DNA damage, based on gene-deficient cell strains models.</p><p><b>METHODS</b>hOGG1 and hMTH1 gene deficient cell strains models were established by Human embryonic lung fibroblasts (HFL) cells. After HFL cells being exposed to 100 µmol/L H₂O₂ for 12 h, HPLC-EC detecting technique and RT-PCR method were adopted to analyze the genetic expression level of 8-oxo-dG (7, 8-dihydro-8-oxoguanine).</p><p><b>RESULTS</b>The gene-deficient cell strains models of hOGG1 and hMTH1 were obtained by infecting target cells with high titer of lentivirus. The mRNA expression level of hOGG1 was 0.09 ± 0.02, 91% lower than it in normal HFL cells, which was 1.00 ± 0.04. As the same, the mRNA expression level of hMTH1 (0.41 ± 0.04) also decreased by 60% compared with it in normal HFL cells (1.02 ± 0.06). After induced by 100 µmol/L H₂O₂ for 12 h, the genetic expression level of hMTH1 in hOGG1 gene-deficient cells (1.26 ± 0.18) increased 25% compared with it in control group (1.01 ± 0.07). Meanwhile, the genetic expression level of hOGG1 in hMTH1 gene-deficient cells (1.54 ± 0.25) also increased by 52%. The DNA 8-oxo-dG levels in hOGG1 gene-deficient cells (2.48 ± 0.54) was 3.1 times compared with it in the control group (0.80 ± 0.16), the difference showed statistical significance (P < 0.01). Whereas the 8-oxo-dG levels in hMTH1 gene-deficient cells (1.84 ± 0.46) was 2.3 times of it in the control group, the difference also showed statistical significance (P < 0.01).</p><p><b>CONCLUSION</b>Based on gene-deficient HFL cells models, a synergetic substitution effect on DNA damage and repair activity by both hOGG1 and hMTH1 were firstly discovered when induced by oxidation. The substitution effect of hOGG1 were stronger than that of hMTH1.</p>


Subject(s)
Cell Line , DNA Damage , DNA Glycosylases , Genetics , DNA Repair , DNA Repair Enzymes , Genetics , Fibroblasts , Metabolism , Humans , Oxidative Stress , Genetics , Phosphoric Monoester Hydrolases , Genetics
11.
Chinese Journal of Pathology ; (12): 668-672, 2014.
Article in Chinese | WPRIM | ID: wpr-304421

ABSTRACT

<p><b>OBJECTIVE</b>To study the correlation between IDH1 mutation, MGMT expression, clinicopathologic features and post-radiotherapy prognosis in patients with astrocytoma.</p><p><b>METHODS</b>Detection of IDH1 mutation and MGMT expression was carried out in 48 cases of astrocytoma (WHO grade II to III) by EnVision method with immunohistochemical staining. Follow-up data, including treatment response and overall survival time, were analyzed.</p><p><b>RESULTS</b>The rates of IDH1 mutation and MGMT expression in astrocytomas were 62.7% (30/48) and 47.9% (23/48), respectively. There was a negative correlation between IDH1 mutation and MGMT expression (r = -0.641, P < 0.01). The age of patients with IDH1 mutation was younger at disease onset. The IDH1 mutation rate in patients with WHO grade II astrocytoma was higher than that in patients with WHO grade III tumor (P < 0.05). The age at onset was an independent factor affecting the expression of mutant IDH1. After radiotherapy, patients with IDH1 mutation+/MGMT- tumor carried a longer overall survival time than patients with IDH1 mutation-/MGMT+ tumor (P < 0.05).</p><p><b>CONCLUSIONS</b>There is a correlation between IDH1 mutation and MGMT expression in WHO grade II to III astrocytoma. Age at onset is an independent factor affecting the expression of mutant IDH1. Tumors with IDH1+/MGMT- pattern show better response to radiotherapy than tumors with IDH1-/MGMT+ pattern. Detection of IDH1 mutation and MGMT protein expression can provide some guidance in choice of treatment modalities in patients with astrocytoma.</p>


Subject(s)
Adult , Age Factors , Age of Onset , Aged , Astrocytoma , Genetics , Metabolism , Mortality , Pathology , Radiotherapy , Brain Neoplasms , Genetics , Metabolism , Mortality , Pathology , Radiotherapy , DNA Modification Methylases , Metabolism , DNA Repair Enzymes , Metabolism , Female , Humans , Isocitrate Dehydrogenase , Genetics , Male , Middle Aged , Mutant Proteins , Genetics , Mutation , Prognosis , Tumor Suppressor Proteins , Metabolism
12.
Article in Chinese | WPRIM | ID: wpr-254465

ABSTRACT

<p><b>OBJECTIVE</b>To identify potential mutations among three sisters from a Chinese family suspected with Cockayne syndrome for growth and psychomotor retardation, and to offer genetic counseling and prenatal diagnosis for the family.</p><p><b>METHODS</b>G-banded karyotyping, microarray comparative genomic hybridization (CM-CGH), whole genome exon high-throughput sequencing and Sanger sequencing were employed to identify potential genetic variations for the three patients and their parents.</p><p><b>RESULTS</b>Whole exome sequencing has identified two novel missense mutations, i.e., c.1595A>G (p.Asp532Gly) and c.1607T>G (p.Leu536Trp), in exon 7 of excision repair cross-complementing rodent repair deficiency, complementation group 6 (ERCC6) gene. Sanger sequencing confirmed that all of the three sisters have inherited one of the mutations (c.1607T>G) from their father and another (c.1595A>G) from their mother.</p><p><b>CONCLUSION</b>Three sisters have all been identified as double heterozygote for mutations c.1607T>G and c.1595A>G and were diagnosed with Cockayne syndrome.</p>


Subject(s)
Adult , Asians , Genetics , Base Sequence , Child, Preschool , Cockayne Syndrome , Diagnosis , Genetics , DNA Helicases , Genetics , DNA Repair Enzymes , Genetics , Exons , Female , Heterozygote , Humans , Infant , Male , Molecular Sequence Data , Pedigree , Point Mutation , Poly-ADP-Ribose Binding Proteins
13.
Clinics ; 68(9): 1255-1262, set. 2013. graf
Article in English | LILACS | ID: lil-687753

ABSTRACT

OBJECTIVE: The aim of this study was to evaluate the effect of a novel phytoestrogen, α-Zearalanol, on Alzheimer's disease-related memory impairment and neuronal oxidation in ovariectomized mice. METHODS: Female C57/BL6 mice were ovariectomized or received sham operations and treatment with equivalent doses of 17β-estradiol or α-Zearalanol for 8 weeks. Their spatial learning and memory were analyzed using the Morris water maze test. The antioxidant enzyme activities and reactive oxygen species generation, neuronal DNA oxidation, and MutT homolog 1 expression in the hippocampus were measured. RESULTS: Treatment with 17β-estradiol or α-Zearalanol significantly improved spatial learning and memory performance in ovariectomized mice. In addition, 17β-estradiol and α-Zearalanol attenuated the decrease in antioxidant enzyme activities and increased reactive oxygen species production in ovariectomized mice. The findings indicated a significant elevation in hippocampi neuronal DNA oxidation and reduction in MutT homolog 1 expression in estrogen-deficient mice, but supplementation with 17β-estradiol or α-Zearalanol efficaciously ameliorated this situation. CONCLUSION: These results demonstrate that α-Zearalanol is potentially beneficial for improving memory impairments and neuronal oxidation damage in a manner similar to that of 17β-estradiol. Therefore, the compound may be a potential therapeutic agent that can ameliorate neurodegenerative disorders related to estrogen deficiency. .


Subject(s)
Animals , Female , Mice , Alzheimer Disease/drug therapy , Estradiol/therapeutic use , Memory Disorders/drug therapy , Ovariectomy , Oxidative Stress/drug effects , Phytoestrogens/therapeutic use , Zeranol/analogs & derivatives , Blotting, Western , DNA Damage/drug effects , DNA Repair Enzymes/analysis , Hippocampus/drug effects , Immunohistochemistry , Phosphoric Monoester Hydrolases/analysis , Reproducibility of Results , Time Factors , Treatment Outcome , Zeranol/therapeutic use
14.
Article in Chinese | WPRIM | ID: wpr-315778

ABSTRACT

<p><b>OBJECTIVE</b>To study the radiobiological characteristic of human nasopharyngeal carcinoma cell lines CNE1 and CNE2 and the changes in expression MRN (Mre11-Rad50-Nbs1) complex in the cell lines exposed to irradiation.</p><p><b>METHODS</b>CNE1 and CNE2 were irradiated by a linear accelerator. Radiobiological characteristics were detected by colony assay and MTT assay. MRN complex expression were examined by Western blot.</p><p><b>RESULTS</b>Surviving fraction at 2 Gy (SF2), quasi-threshold Dose (Dq), and mean lethal dose (Do) of CNE1 were 0.56, 1.449 Gy and 1.480 Gy; SF2, Dq, and Do of CNE2 were 0.44, 0.776 Gy and 1.685 Gy, respectively. Survival fraction of CNE1 at the day 6 after 4 Gy irradiation was 0.59 and that of CNE2 was 0.79 when compared with control, with the up-regulated expressions of Rad50 in CNE1 and Mre11, Rad50 and Nbs1 in CNE2 (P < 0.05).</p><p><b>CONCLUSIONS</b>CNE1 and CNE2 were sensitive to radiation, but there were radioresistance cells in CNE2. The expressions of some components of MRN complex were up-regulated to repair DNA lesions induced by radiation.</p>


Subject(s)
Carcinoma , Cell Cycle Proteins , Metabolism , Cell Line, Tumor , Radiation Effects , DNA Repair , DNA Repair Enzymes , Metabolism , DNA-Binding Proteins , Metabolism , Gene Expression Regulation, Neoplastic , Humans , MRE11 Homologue Protein , Nasopharyngeal Neoplasms , Pathology , Radiotherapy , Nuclear Proteins , Metabolism , Radiation Tolerance
15.
Article in Chinese | WPRIM | ID: wpr-275808

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the association between ERCC6 gene polymorphisms and peripheral blood lymphocyte DNA damage among the workers in coking plant.</p><p><b>METHODS</b>By cluster sampling, 379 coke oven workers having worked for 8 hours were included in the exposure group, 398 coke oven workers having rested for more than 16 hours were included in the recovery group, and 398 workers having never been exposed to polycyclic aromatic hydrocarbons (PAHs) in the same plant were included in the control group. Lymphocytes were separated from their peripheral venous blood, and single cell gel electrophoresis was used to evaluate DNA damage; TaqMan-MGB probes were used to analyze ERCC6 gene polymorphisms. PHASE 2.0.2 genetic analysis software was used to calculate the haplotypes.</p><p><b>RESULTS</b>The Olive tail moment (OTM) of lymphocytes in the exposure group was significantly higher than those in the recovery group and control group (-0.86±0.70 vs -1.14±0.68 and -1.13±0.65, P < 0.05). In the exposure group, for workers ≥37 years old, the OTM of lymphocytes in workers carrying CG+GG genotype at rs3793784 locus of ERCC6 gene was significantly lower than that in workers carrying CC genotype (P < 0.05); the OTM of lymphocytes in workers <37years old carrying CC genotype at rs3793784 locus of ERCC6 gene was significantly lower than that in workers ≥37 years old carrying CC genotype (P < 0.05); the OTMof lymphocytes in workers <37 years old carrying CG+GG genotype at rs3793784 locus of ERCC6 gene was significantly higher than that in workers ≥37 years old carrying CG+GG genotype (P < 0.05). For patients with internal exposure, in the 1-hydroxypyrene >4.36 ümol/L group, the OTM of lymphocytes in workers carrying AG+GG genotype was significantly higher than that in workers carrying AA genotype (P < 0.05).</p><p><b>CONCLUSION</b>Different genotypes of ERCC6 gene rs3793784 in peripheral blood lymphocytes of coke oven workers exposed to PAHs have different functions at different ages, suggesting that genotype may interact with age in population exposed to PAHs.</p>


Subject(s)
Adult , Coke , DNA Damage , DNA Helicases , Genetics , DNA Repair Enzymes , Genetics , Genotype , Humans , Lymphocytes , Middle Aged , Occupational Exposure , Poly-ADP-Ribose Binding Proteins , Polymorphism, Single Nucleotide
16.
Chinese Journal of Pathology ; (12): 655-659, 2013.
Article in Chinese | WPRIM | ID: wpr-288242

ABSTRACT

<p><b>OBJECTIVE</b>To analyze immunophenotypes and gene mutations of colorectal precancerous lesions and adenocarcinoma, and to compare the difference of carcinogenetic mechanisms between the two precancerous lesions.</p><p><b>METHODS</b>Fifty-three cases of colorectal serrated lesions including 30 hyperplastic polyps, 20 sessile serrated adenomas (SSA) and 3 mixed polyps were collected from January 2006 to June 2012.Forty-five cases of traditional adenomas and 50 cases of colorectal adenocarcinomas were also recruited. Thirty hyperplastic polyps, 20 cases of SSA, 3 mixed polyps and 45 traditional adenomas were investigated by immunohistochemistry for the expression of DNA mismatch repair (MMR) proteins (MLH1, MSH2 and MSH6) and DNA methyltransferase MGMT. Mutations of KRAS, BRAF and PIK3CA genes in 10 cases of SSAs, 10 traditional adenomas, 1 mixed polyps and 50 colorectal adenocarcinomas were analyzed by PCR followed by direct Sanger sequencing.</p><p><b>RESULTS</b>(1) Only 3 cases of hyperplastic polyps lost MLH1 expression, and none of SSAs or traditional adenomas showed loss of MLH1. The negative expression rates of MSH2, MSH6 and MGMT in hyperplastic polyps and SSA were significantly higher than those of traditional adenomas. (2) KRAS mutation was found in 5/10 cases of SSAs, 5/10 traditional adenomas and 1/1 mixed polyps. (3) Colorectal adenocarcinomas harbored the mutations of KRAS (48%, 24/50), BRAF (6%, 3/50) and PIK3CA (4%, 2/50).</p><p><b>CONCLUSIONS</b>Immunophenotypic and gene mutation profiles are different between colorectal serrated lesion and traditional adenoma. Alterations of MMR and MGMT expression play important roles in the pathogenesis of "serrated neoplasm". KRAS mutation is a significant genetic change in the early phase of colorectal carcinogenesis.</p>


Subject(s)
Adaptor Proteins, Signal Transducing , Metabolism , Adenocarcinoma , Genetics , Metabolism , Adenoma , Genetics , Metabolism , Aged , Class I Phosphatidylinositol 3-Kinases , Colonic Polyps , Genetics , Metabolism , Colorectal Neoplasms , Genetics , Metabolism , DNA Mismatch Repair , DNA Modification Methylases , Metabolism , DNA Repair Enzymes , Metabolism , DNA, Neoplasm , Metabolism , DNA-Binding Proteins , Metabolism , Female , Humans , Hyperplasia , Immunophenotyping , Male , Middle Aged , MutL Protein Homolog 1 , MutS Homolog 2 Protein , Metabolism , Nuclear Proteins , Metabolism , Phosphatidylinositol 3-Kinases , Genetics , Point Mutation , Precancerous Conditions , Genetics , Metabolism , Proto-Oncogene Proteins , Genetics , Proto-Oncogene Proteins B-raf , Genetics , Proto-Oncogene Proteins p21(ras) , Sequence Analysis, DNA , Tumor Suppressor Proteins , Metabolism , ras Proteins , Genetics
17.
Braz. j. microbiol ; 43(1): 309-324, Jan.-Mar. 2012. ilus, tab
Article in English | LILACS | ID: lil-622819

ABSTRACT

Previously isolated 115 endospore-forming bacilli were basically grouped according to their temperature requirements for growth: the thermophiles (74%), the facultative thermophiles (14%) and the mesophiles (12%). These isolates were taken into 16S rRNA gene sequence analyses, and they were clustered among the 7 genera: Anoxybacillus, Aeribacillus, Bacillus, Brevibacillus, Geobacillus, Paenibacillus, and Thermoactinomycetes. Of these bacilli, only the thirty two isolates belonging to genera Bacillus (16), Brevibacillus (13), Paenibacillus (1) and Thermoactinomycetes (2) were selected and presented in this paper. The comparative sequence analyses revealed that the similarity values were ranged as 91.4-100 %, 91.8- 99.2 %, 92.6- 99.8 % and 90.7 - 99.8 % between the isolates and the related type strains from these four genera, respectively. Twenty nine of them were found to be related with the validly published type strains. The most abundant species was B. thermoruber with 9 isolates followed by B. pumilus (6), B. lichenformis (3), B. subtilis (3), B. agri (3), B. smithii (2), T. vulgaris (2) and finally P. barengoltzii (1). In addition, isolates of A391a, B51a and D295 were proposed as novel species as their 16S rRNA gene sequences displayed similarities ¡Ü 97% to their closely related type strains. The AluI-, HaeIII- and TaqI-ARDRA results were in congruence with the 16S rRNA gene sequence analyses. The ARDRA results allowed us to differentiate these isolates, and their discriminative restriction fragments were able to be determined. Some of their phenotypic characters and their amylase, chitinase and protease production were also studied and biotechnologically valuable enzyme producing isolates were introduced in order to use in further studies.


Subject(s)
Gram-Positive Endospore-Forming Rods/genetics , Gram-Positive Endospore-Forming Rods/isolation & purification , DNA Repair Enzymes , RNA , Environmental Microbiology
18.
Indian J Cancer ; 2012 Jan-Mar; 49(1): 144-162
Article in English | IMSEAR | ID: sea-144565

ABSTRACT

Genetic influences on cancer development have been extensively investigated during the last decade following publication of human genome sequence. The present review summarizes case-control studies on genetic polymorphisms and cancer risk in Indians. It is observed that the most commonly studied genes in the Indian population included members of phase I and phase II metabolic enzymes. Other than these genes, genetic polymorphisms for cell cycle and apoptosis-related factors, DNA repair enzymes, immune response elements, growth factors, folate metabolizing enzymes, vitamin/hormone receptors, etc., were investigated. Several studies also evidenced a stronger risk for combined genotypes rather than a single polymorphism. Gene-environment interaction was also found to be a determining factor for cancer development in some experiments. Data for single polymorphism and single cancer type, however, was insufficient to validate an association. It appears that much more experiments involving larger sample size, cross-tabulating genetic polymorphisms and environmental factors are required in order to identify genetic markers for different cancers in Indian populations.


Subject(s)
Cell Cycle Proteins/genetics , DNA Repair Enzymes/genetics , Genes, MHC Class II , Genetic Association Studies , Humans , India , Intercellular Signaling Peptides and Proteins/genetics , Metabolic Detoxication, Phase I/genetics , Metabolic Detoxication, Phase II/genetics , Neoplasms/genetics , Polymorphism, Genetic
19.
Article in Chinese | WPRIM | ID: wpr-747008

ABSTRACT

OBJECTIVE@#To explore the correlation between histone H3-K9 methylation, DNA methylation and expression of carcinoma suppressor gene MGMT in laryngeal carcinoma Hep-2 cell line.@*METHOD@#5-Aza-dC was used to deal with Hep-2 cell cultured in vitro. ChIP, MSP and Realtime-PCR were used to detect H3-K9 methylation, DNA methylation, of MGMT gene promoter region and MGMT gene expression before and after treatment with drugs.@*RESULT@#(1) In Hep-2 cell line, gene MGMT was characterized by DNA methylation and histone H3-K9 hypermethylation. (2) 5-Aza-dC was able to reduce H3-K9 methylation of MGMT gene histone in Hep-2 cell line, 5-Aza-dC was able to reverse DNA methylation of MGMT gene histone in Hep-2 cell line, 5-Aza-dC was able to upregulate the down-regulated gene expression of tumor suppressor genes MGMT.@*CONCLUSION@#Promoter methylation of cancer suppressor gene MGMT may induce the gene inactivity. DNA methylation may increase H3-K9 methylation. 5-Aza-dC can reduce H3-K9 methylation of tumor suppressor gene MGMT histone by reversing DNA methylation of tumor suppressor gene MGMT, and then the expression of tumor suppressor genes is increased and tumor development is inhibited.


Subject(s)
Cell Line, Tumor , DNA Methylation , DNA Modification Methylases , Genetics , Metabolism , DNA Repair Enzymes , Genetics , Metabolism , Genes, Tumor Suppressor , Histones , Metabolism , Humans , Laryngeal Neoplasms , Genetics , Metabolism , Pathology , Tumor Suppressor Proteins , Genetics , Metabolism
20.
Article in Chinese | WPRIM | ID: wpr-355622

ABSTRACT

<p><b>OBJECTIVE</b>To observe the effects of Dujieqing Oral Liquid (DJQ) on the promoter methylation of the O6-methylguanine-DNA methyltransferase (MGMT) gene in the plasma DNA samples from middle-and-late stage tumor patients receiving chemotherapy.</p><p><b>METHODS</b>Recruited 60 patients were randomly assigned to the treatment group (treated by conventional chemotherapy combined DJQ, 20 mL each time, three times daily) and the control group (treated by chemotherapy alone), 30 in each group. The therapeutic course was 8 weeks. The promoter methylation of the MGMT gene in the plasma DNA samples form middle-and-late stage tumor patients receiving chemotherapy was detected before and after treatment using nested methylation-specific polymerase chain reaction (MSP). Meanwhile, the peripheral hemogram was detected. The clinical efficacy and toxic/adverse reactions were assessed using Karnofsky performance scale (KPS).</p><p><b>RESULTS</b>Results of the promoter methylation of MGMT genes showed that methylation rate was 20.00% in the treatment group and 46.67% in the control group (P<0.05). Compared with before treatment, the KPS was significantly improved in the treatment group after treatment, while it significantly decreased in the control group after treatment (both P<0.05). There was statistical difference in the KPS between the two groups after treatment (P<0.01). The toxic/adverse reactions were milder in the treatment group than in the control group (P<0.01).</p><p><b>CONCLUSIONS</b>DJQ showed efficiency synergism and toxicity reducing effects, but with no effect on the hematopoietic function of the bone marrow. MGMT gene was indicated as DJQ's target point for efficiency synergism and toxicity reducing. The efficiency synergism and toxicity reducing effects were achieved by regulating the activities of MGMT gene.</p>


Subject(s)
Adult , Aged , DNA Methylation , DNA Modification Methylases , Genetics , DNA Repair Enzymes , Genetics , Drugs, Chinese Herbal , Pharmacology , Therapeutic Uses , Female , Humans , Male , Middle Aged , Neoplasm Staging , Neoplasms , Genetics , Metabolism , Pathology , Promoter Regions, Genetic , Tumor Suppressor Proteins , Genetics
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