Cloning, Molecular ; DNA ; genetics ; DNA-Binding Proteins ; genetics ; Humans ; Proteins ; genetics ; Sequence Analysis, DNA ; Two-Hybrid System Techniques ; Yeasts ; genetics

BACKGROUNDConflicting results about the association between expression level of excision repair cross-complementation group 1 (ERCC1) and clinical outcome in patients with colorectal cancer (CRC) receiving chemotherapy have been reported. Thus, we searched the available articles and performed the meta-analysis to elucidate the prognostic role of ERCC1 expression in patients with CRC.

METHODSA thorough literature search using PubMed (Medline), Embase, Cochrane Library, Web of Science databases, and Chinese Science Citation Database was conducted to obtain the relevant studies. Pooled hazard ratios (HR s) or odds ratios (OR s) with 95% confidence intervals (CI s) were calculated to estimate the results.

RESULTSA total of 11 studies were finally enrolled in this meta-analysis. Compared with patients with lower ERCC1 expression, patients with higher ERCC1 expression tended to have unfavorable overall survival (OS) (HR = 2.325, 95% CI: 1.720-3.143, P < 0.001), progression-free survival (PFS) (HR = 1.917, 95% CI: 1.366-2.691, P < 0.001) and poor response to chemotherapy (OR = 0.491, 95% CI: 0.243-0.990, P = 0.047). Subgroup analyses by treatment setting, ethnicity, HR extraction, detection methods, survival analysis, and study design demonstrated that our results were robust.

CONCLUSIONSERCC1 expression may be taken as an effective prognostic factor predicting the response to chemotherapy, OS, and PFS. Further studies with better study design and longer follow-up are warranted in order to gain a deeper understanding of ERCC1's prognostic value.

Colorectal Neoplasms ; drug therapy ; mortality ; DNA-Binding Proteins ; analysis ; Endonucleases ; analysis ; Humans ; Immunohistochemistry ; Prognosis

OBJECTIVETo construct DNA double-strand break (DSB) repair protein hKu70 deficient cell strain and to observe its biological characters for studying the functions of hKu70 gene and the effects of occupational harmfulness factors on DSB repair.

METHODSHuman lung fibroblasts (HLF) were transfected with the eukaryotic expression plasmids of hKu70 gene antisense RNA (pEGFP-C1-K) to construct hKu70 protein deficient cells (named as "HLFK"). The protein expression levels of hKu70 gene in HLFC and HLFK were detected by the Western blotting to estimate the effects of antisense inhibition. Morphology, growth character and growth status in soft agar of transfected HLFK were observed.

RESULTSpEGFP-C1-K vector was successfully expressed in HLF. The protein expression level of hKu70 gene in HLFK was decreased by 42% as compared with that in HLFC. No obvious changes of the biologic characters were observed in HLFK.

CONCLUSIONThe hKu70 protein deficient cell strain was successfully constructed. The hKu70 protein deficiency alone didn't induce obvious changes of the biological characters in HLFK.

Antigens, Nuclear ; analysis ; Cell Division ; DNA Damage ; DNA Helicases ; DNA Repair ; DNA-Binding Proteins ; analysis ; deficiency ; Humans ; Ku Autoantigen ; RNA, Antisense ; Transfection

OBJECTIVETo investigate the expression of nesfatin-1/NUCB2 and ghrelin in the gastric mucosa of rats with intrauterine growth retardation (IUGR) and its significance.

METHODSThe IUGR animal model was established by feeding rats low-protein diets during their pregnancy. Newborn rats were divided into catch-up growth, non-catch-up growth and control groups. Protein and mRNA levels of nesfatin-1/NUCB2 and ghrelin in the gastric mucosa of rats were determined by RT-PCR and Western blot, respectively.

RESULTSNesfatin-1/NUCB2 mRNA and protein were expressed in the gastric mucosa of rats immediately after birth, and their expression increased in an age-dependent manner in all three groups. Furthermore, the level of nesfatin-1/NUCB2 in the catch-up growth group was higher than that in the control group before weaning, whereas there was no significant difference in nesfatin-1/NUCB2 expression between the two groups after weaning. The level of nesfatin-1/NUCB2 in the non-catch-up growth group was lower than that in the catch-up growth group during the whole observation period. The level of ghrelin in the catch-up growth group was higher than that in the control group starting from day 12 after birth, whereas there was no significant difference in ghrelin expression between the two groups after weaning. The level of ghrelin in the non-catch-up growth group was lower compared with those in the catch-up growth and control groups from days 12 to 28 after birth.

CONCLUSIONSNesfatin-1 and ghrelin are co-expressed in the gastric mucosa of rats with IUGR after birth and interact with each other to produce long-term nutritional regulation.

Age Factors ; Animals ; Calcium-Binding Proteins ; analysis ; genetics ; DNA-Binding Proteins ; analysis ; genetics ; Female ; Fetal Growth Retardation ; metabolism ; Gastric Mucosa ; chemistry ; Ghrelin ; analysis ; genetics ; Male ; Nerve Tissue Proteins ; analysis ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley

BACKGROUNDNurr1 is a member of the nuclear receptor superfamily of transcription factors. The objective of the present study was to identify novel splicing variants of the gene in neuronal and non-neuronal tissues and determine their functions.

METHODSReverse transcription-polymerase chain reaction (RT-PCR) analysis was used to screen for Nurr1 splice variants in the adult human central nervous system (CNS) and in other tissues such as lymphocytes, and liver, muscle, and kidney cells. Functional assays of the variants were performed by measuring Nurr1 response element (NuRE) transcriptional activity in vitro.

RESULTSIn this study, the authors identified a novel splicing variant of Nurr1 within exon 5, found in multiple adult human tissues, including lymphocytes, and liver, muscle, and kidney cells, but not in the brain or spinal cord. Sequencing analysis showed the variant has a 75 bp deletion between nucleotides 1402 and 1476. A functional assay of the Nurr1-c splicing variant, performed by measuring NuRE transcriptional activity in vitro, detected a 39% lower level of luciferase (LUC) activity (P < 0.05).

CONCLUSIONA novel splicing variant of Nurr1 exists in human non-neuronal tissues and functional assays suggest that the variant may act as an alternate transcription regulator.

Adult ; Alternative Splicing ; DNA-Binding Proteins ; analysis ; genetics ; Humans ; Nuclear Receptor Subfamily 4, Group A, Member 2 ; Transcription Factors ; analysis ; genetics

To determine the feasibility of a nonradioactive electrophoresis mobility shift assay for detecting nuclear transcription factor, double-stranded oligonucleotides encoding the consensus target sequence of NF-kappa B were labelled with DIG by terminal transferase. After nuclear protein stimulated with phorbol 12-myristate 13-acetate (PMA) or PMA and pyrrolidine dithiocarbamate (PDTC) electrophoresed on 8% nondenaturing poliacrylamide gel together with oligeonucleotide probe, they were electro-blotted nylon membrane positively charged. Anti-DIG-AP antibody catalyzed chemiluminescent substrate CSPD to image on X-film. The results showed that nuclear proteins binded specifically to the NF-kappa B consensus sequence in the EMSA by chemiluminescent technique method and the activity of NF-kappa B in PMA group was more than that in PMA + PDTC group. It is suggested that detection of NF-kappa B by EMSA with chemiluminescent technique is feasible and simple, which can be performed in ordinary laboratories.
Chemiluminescent Measurements ; DNA-Binding Proteins/*analysis ; DNA-Binding Proteins/genetics ; Electrophoretic Mobility Shift Assay ; NF-kappa B/*analysis ; NF-kappa B/genetics ; NF-kappa B/metabolism ; Rats, Sprague-Dawley ; *Trans-Activation (Genetics) ; Trans-Activators/analysis ; Trans-Activators/genetics ; *Transcription, Genetic

BACKGROUND/AIMS: In order to identify microsatellite instability (MSI), the test based on the polymerase chain reaction (PCR) can be used. However, PCR is not routinely performed in all hospital laboratories. Recently, immunohistochemistry (IHC) for MLH1 and MSH2 proteins has been reported as a rapid and useful method for MSI. However, the efficacy of IHC in the detection of the MSI has not been well established. The aim of this study was to evaluate the usefulness of IHC in the detection of the MSI by comparing it with the test results using PCR in colorectal cancer (CRC). METHODS: Paraffin-embedded normal and tumor tissues from seventy-five patients who underwent surgical resection of CRC were used. Abnormal expression of MLH1 and MSH2 protein was determined by IHC using MLH1 and MSH2 antibodies. Normal and tumor DNAs were obtained from thirty CRC tissues that showed abnormal expression of MLH1 and MSH2 proteins by IHC. The MSI status was confirmed by PCR using five markers. RESULTS: Thirty tumors showed abnormal expression of MLH1 and MSH2 proteins by IHC, but only three tumors out of them were confirmed to have MSI by PCR. CONCLUSIONS: This result suggests that IHC with MLH1 and MSH2 antibodies does not seem to be a useful method to identify MSI in CRC, therefore PCR is required for detection of the MSI.
Adaptor Proteins, Signal Transducing ; Aged ; Carrier Proteins ; Colorectal Neoplasms/*genetics ; DNA-Binding Proteins/*analysis ; Female ; Humans ; Immunohistochemistry ; Male ; *Microsatellite Repeats ; Middle Aged ; MutS Homolog 2 Protein ; Neoplasm Proteins/*analysis ; Nuclear Proteins ; Polymerase Chain Reaction ; Proto-Oncogene Proteins/*analysis

We expressed recombinant single-stranded DNA-binding protein (r-SSBP) from Escherichia coli with the molecular weight of 24-kDa by using genetic engineering strategy, and demonstrated the single-stranded DNA (ssDNA)-binding activity of r-SSBP by electrophoretic mobility shift assay (EMSA). To further characterize r-SSBP, we studied the effects of r-SSBP on melting temperature (T(m)) of DNA. The results showed that r-SSBP could bind to ssDNA, and lower the T(m) of DNA, especially for single-base mismatched DNA. Therefore, r-SSBP significantly increased the T(m) difference between single-base mismatched DNA and perfect matched DNA. These results are very beneficial for single-nucleotide polymorphism detection. Moreover, we applied r-SSBP in high sensitive pyrosequencing system developed by our group. The results suggest that the r-SSBP decreased non-specific signals, corrected the proportion of signal peak height and improved the performance of pyrosequencing.
DNA-Binding Proteins ; biosynthesis ; genetics ; Diphosphates ; metabolism ; Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; Recombinant Proteins ; biosynthesis ; genetics ; Sequence Analysis, DNA ; methods

High selectivity provided by biomolecules such as antibodies and enzymes has been exploited during the last two decades for development of biosensors. Of particular importance are efficient immobilization methods for biomolecules in order to preserve their biological activities. In this study, we have evaluated immobilization strategies for an anti-DNA antibody on a self-assembled monolayer of omega-functionalized thiols. The antibody was immobilized via peptide bond formation between the primary amines in the antibody and the carboxyl groups on the self-assembled monolayer. The peptide bond coupling was achieved by activating COOH groups on the surface through N-Hydroxysuccimide (NHS)-ester formation, followed by acylation of NH2 group in the antibody. DNA binding activity of the immobilized antibody was examined by counting beta emission from 35S-labeled DNA.
Antibodies, Antinuclear* ; DNA/immunology ; DNA/analysis* ; DNA-Binding Proteins/chemistry ; Gold ; Membranes, Artificial ; Polymerase Chain Reaction ; Polyvinyls/chemistry ; Radioimmunoassay/methods* ; Thioctic Acid/chemistry

To investigate the change of telomerase activity and human telomerase reverse transcriptase (hTERT) gene expression in HL-60 cells transfected with wild type p53 gene, wild type p53 gene was introduced into HL-60 cells by Lipofectin transfection. Apoptosis was analyzed by TUNEL assay. Telomerase activity and the level of hTERT mRNA were detected by telomeric repeat amplification protocol (TRAP)-ELISA and RT-PCR, respectively. The results showed that the apoptotic rate of HL-60-pN53cG cells was 8.3% and 21.0% respectively after cultured at 32.5 degrees C for 24 h and 72 h. The level of hTERT mRNA was decreased to 68.4% and 55.8% and telomerase activity to 27.3% and 8.9% of control value in HL-60-pN53cG cells at the same points. In conclusions, hTERT mRNA and telomerase activity were down-regulated in HL-60 cells transfected with p53 gene. This may be one of mechanisms of apoptosis induced by wild type p53 gene.
Apoptosis ; DNA-Binding Proteins ; Gene Expression ; Genes, p53 ; physiology ; HL-60 Cells ; Humans ; RNA, Messenger ; analysis ; Telomerase ; genetics ; metabolism