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.
Adaptor Proteins, Signal Transducing/deficiency/metabolism ; Adenosine Triphosphatases/deficiency/metabolism ; Adult ; Aged ; Aged, 80 and over ; Chemotherapy, Adjuvant ; *DNA Mismatch Repair ; DNA Repair Enzymes/deficiency/*metabolism ; DNA-Binding Proteins/deficiency/*metabolism ; Endometrial Neoplasms/*diagnosis/drug therapy/genetics/pathology ; Female ; Humans ; Kaplan-Meier Estimate ; Middle Aged ; MutS Homolog 2 Protein/deficiency/metabolism ; Neoplasm Proteins/deficiency/metabolism ; Nuclear Proteins/deficiency/metabolism ; Prognosis ; Retrospective Studies ; Tumor Markers, Biological/*metabolism

OBJECTIVETo explore the relationship between DNA mismatch repair (MMR) and clinicopathologic features and prognosis in patients with stages II and III colon cancers.

METHODSThe 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.

RESULTSOf 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).

CONCLUSIONSDefective 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.

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

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
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 ; immunology ; Immunoglobulin G ; blood ; Mice ; Mice, Inbred BALB C ; Recombinant Proteins ; genetics ; immunology ; Schistosoma japonicum ; genetics ; metabolism ; Schistosomiasis japonica ; prevention & control ; Vaccines ; immunology

OBJECTIVETo study the correlation between IDH1 mutation, MGMT expression, clinicopathologic features and post-radiotherapy prognosis in patients with astrocytoma.

METHODSDetection 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.

RESULTSThe 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).

CONCLUSIONSThere 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.

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

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.
Aged ; Antineoplastic Agents, Alkylating ; therapeutic use ; Brain Neoplasms ; genetics ; metabolism ; therapy ; Chemoradiotherapy ; DNA Methylation ; DNA Modification Methylases ; genetics ; metabolism ; DNA Repair Enzymes ; genetics ; metabolism ; Dacarbazine ; analogs & derivatives ; therapeutic use ; Dose Fractionation ; Glioblastoma ; genetics ; metabolism ; therapy ; Humans ; Radiosurgery ; Tumor Suppressor Proteins ; genetics ; metabolism

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.
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 ; Receptor, Epidermal Growth Factor ; metabolism ; Tumor Suppressor Proteins ; genetics ; metabolism

OBJECTIVETo investigate the potential substitution effect of hOGG1 and hMTH1 on oxidative DNA damage, based on gene-deficient cell strains models.

METHODShOGG1 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).

RESULTSThe 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).

CONCLUSIONBased 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.

Cell Line ; DNA Damage ; DNA Glycosylases ; genetics ; DNA Repair ; DNA Repair Enzymes ; genetics ; Fibroblasts ; metabolism ; Humans ; Oxidative Stress ; genetics ; Phosphoric Monoester Hydrolases ; genetics

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; Adenosine Triphosphatases ; genetics ; metabolism ; DNA Mismatch Repair ; DNA Repair Enzymes ; genetics ; metabolism ; DNA-Binding Proteins ; genetics ; metabolism ; Endometrial Neoplasms ; etiology ; genetics ; metabolism ; pathology ; Female ; Genetic Predisposition to Disease ; Humans ; Lynch Syndrome II ; complications ; genetics ; metabolism ; pathology ; Mismatch Repair Endonuclease PMS2 ; MutL Protein Homolog 1 ; MutS Homolog 2 Protein ; genetics ; metabolism ; Mutation ; Nuclear Proteins ; genetics ; metabolism

OBJECTIVETo analyze immunophenotypes and gene mutations of colorectal precancerous lesions and adenocarcinoma, and to compare the difference of carcinogenetic mechanisms between the two precancerous lesions.

METHODSFifty-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.

RESULTS(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).

CONCLUSIONSImmunophenotypic 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.

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

OBJECTIVETo 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.

METHODSRecruited 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).

RESULTSResults 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).

CONCLUSIONSDJQ 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.

Adult ; Aged ; DNA Methylation ; DNA Modification Methylases ; genetics ; DNA Repair Enzymes ; genetics ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Humans ; Male ; Middle Aged ; Neoplasm Staging ; Neoplasms ; genetics ; metabolism ; pathology ; Promoter Regions, Genetic ; Tumor Suppressor Proteins ; genetics