Objective To investigate the apoptosis in gastric cancer induced by trichosanthin (TCS) and the relationship between this apoptosis and expression of c-myc. Methods In in vitro experiment, morphologic test and TUNEL s...Objective To investigate the apoptosis in gastric cancer induced by trichosanthin (TCS) and the relationship between this apoptosis and expression of c-myc. Methods In in vitro experiment, morphologic test and TUNEL staining method were used to detect quantitatively and qualitatively the apoptosis status of gastric adenocarcinoma cell line SGC-7901 before and after the treatment of 0.1μg/ml TCS. Immunohistochemical staining method and Northern Blot hybridization were used to detect the expression status of apoptosis-related genes c-myc before and after TCS treatment. Results Some typical apoptotic morphologic changes appeared after 36h treated by TCS. The apoptotic indexes increased significantly in the TCS treated group than those of the untreated group after 36h,42h and 48h (P<0.01). After 24h treated by TCS, an increased expression of c-myc protein product occurred, the staining density was increased from + or ++ to +++ (P< 0.01), and the expression of c-myc RNA increased significantly (P<0.05). Conclusion TCS is able to induce the apoptosis in gastric cancer. This apoptosis may be mediated by up-expression of apoptosis-regulated gene c-myc.展开更多
A library of 2 ×107 random octapeptides was constructed by use of phagemid-based monovalent phage display system. The randomly synthesized degenerated oligodeoxyribonucleotides (oligos ) were fused to the truncat...A library of 2 ×107 random octapeptides was constructed by use of phagemid-based monovalent phage display system. The randomly synthesized degenerated oligodeoxyribonucleotides (oligos ) were fused to the truncated g Ⅲ (p230-p403). Sequence analysis of 11 randomly chosen clones suggested that the degenerated inserts and its deduced amino acid (aa) sequences are randomly distributed. The library was used to select binding peptides to the monoclonal antibody (mAb) 9E10, which recognizes a continuous decapeptide epi- tope of denatured human c-myc protein. After four to five rounds of panning, most of the eluted clones could bind to 9E10. Sequence analysis of the selected positive clones indicated that the binding sequences could fall into two classes, one class (clone 1) shares a consensus motif, ISE x x L, with c-myc decapeptide; and the sequences of the other class are entirely different. The binding of both classes to 9E10 could be specifically inhibited by free c-myc decapeptide. The immunogenicity of the phage peptide was further investigated by construction of multivalent displayed phage peptides and immunization of animals with or without adjuvant. ELISA and competitive ELISA showed that anti-serum from both mice and rabbit immunized with either clone could bind to the original antigen, c-myc decapeptide. These results denote that in spite of the dissimilarity of the selected peptides with c-myc decapeptide, they are capable of inducing similar immune respones in vivo, thus actually mimicking the antigen epitope.展开更多
This paper describes an approach to seek for mouse c-Myc/Myn proteins-bound specific sequences among ge-nomic DNA. cDNA fragment of myn gene was obtained through RT-PCR technique from RNA of NIH3T3 cells. DNA fragment...This paper describes an approach to seek for mouse c-Myc/Myn proteins-bound specific sequences among ge-nomic DNA. cDNA fragment of myn gene was obtained through RT-PCR technique from RNA of NIH3T3 cells. DNA fragments encoding BR/HLH/LZ structure of Myc and Myn proteins were cloned in frame into pGEX-2T vec-tor respectively Fusion GST-Myc and GST-Myn synthe-sized in E.coli hosts showed affinity to CACGTG E-boxDNA and subsequently interacted with genomic fragments prepared through whole-genome-PCR. A PCR-assisted procedure which combines protein-DNA interaction and affinity chromatography was designed to enrich Myc/Myn bound DNA. At least two genomic DNA fragments ob- tained exhibit specifical binding capacity to Myc/Myn complex but not to GST alone. Significance of the work and of the technique itself as well as identification of the DNAs are discussed.展开更多
Objective： To investigate the mechanism of herb cake-partitioned moxibustion treating ulcerative colitis （UC） from the relationship between expression of p53 and C-myc protein, and morbidity of UC. Methods： Rats m...Objective： To investigate the mechanism of herb cake-partitioned moxibustion treating ulcerative colitis （UC） from the relationship between expression of p53 and C-myc protein, and morbidity of UC. Methods： Rats model of UC was made with immune methods and local stimulation. Forty SD rats were divided into normal, model, herb cake-partitioned, and mild moxibustion group by a random number table, 10 rats in each group. Hanging moxibustion in the mild moxibustion group was applied to Tianshu （ST 25） and Qihai （CV 6） for 10 rain. Two moxa cones of herb cake-partitioned moxibustion were applied to the same acupoints respectively, in the herb cake-partitioned moxibustion group. Expression of p53 and C-myc protein was measured with immuno- histochemistical method in the colonic tissue of rats with UC. Results： Postive area, strength, and the immunohistochemistry index of the expression of p53 and C-myc protein were found more in the model rats than those in the normal rats （P〈0.01）, whereas less in the herb cake-partitioned moxibustion and mild moxibustion groups than those in the model group （P〈0.01）. Conclusion： p53 and C-myc play important roles in the morbidity and development of UC, and herb cake-partitioned moxibustion could regulate the expression of p53 and C-myc protein in the colonic tissue of UC rats.展开更多
文摘Objective To investigate the apoptosis in gastric cancer induced by trichosanthin (TCS) and the relationship between this apoptosis and expression of c-myc. Methods In in vitro experiment, morphologic test and TUNEL staining method were used to detect quantitatively and qualitatively the apoptosis status of gastric adenocarcinoma cell line SGC-7901 before and after the treatment of 0.1μg/ml TCS. Immunohistochemical staining method and Northern Blot hybridization were used to detect the expression status of apoptosis-related genes c-myc before and after TCS treatment. Results Some typical apoptotic morphologic changes appeared after 36h treated by TCS. The apoptotic indexes increased significantly in the TCS treated group than those of the untreated group after 36h,42h and 48h (P<0.01). After 24h treated by TCS, an increased expression of c-myc protein product occurred, the staining density was increased from + or ++ to +++ (P< 0.01), and the expression of c-myc RNA increased significantly (P<0.05). Conclusion TCS is able to induce the apoptosis in gastric cancer. This apoptosis may be mediated by up-expression of apoptosis-regulated gene c-myc.
文摘A library of 2 ×107 random octapeptides was constructed by use of phagemid-based monovalent phage display system. The randomly synthesized degenerated oligodeoxyribonucleotides (oligos ) were fused to the truncated g Ⅲ (p230-p403). Sequence analysis of 11 randomly chosen clones suggested that the degenerated inserts and its deduced amino acid (aa) sequences are randomly distributed. The library was used to select binding peptides to the monoclonal antibody (mAb) 9E10, which recognizes a continuous decapeptide epi- tope of denatured human c-myc protein. After four to five rounds of panning, most of the eluted clones could bind to 9E10. Sequence analysis of the selected positive clones indicated that the binding sequences could fall into two classes, one class (clone 1) shares a consensus motif, ISE x x L, with c-myc decapeptide; and the sequences of the other class are entirely different. The binding of both classes to 9E10 could be specifically inhibited by free c-myc decapeptide. The immunogenicity of the phage peptide was further investigated by construction of multivalent displayed phage peptides and immunization of animals with or without adjuvant. ELISA and competitive ELISA showed that anti-serum from both mice and rabbit immunized with either clone could bind to the original antigen, c-myc decapeptide. These results denote that in spite of the dissimilarity of the selected peptides with c-myc decapeptide, they are capable of inducing similar immune respones in vivo, thus actually mimicking the antigen epitope.
文摘This paper describes an approach to seek for mouse c-Myc/Myn proteins-bound specific sequences among ge-nomic DNA. cDNA fragment of myn gene was obtained through RT-PCR technique from RNA of NIH3T3 cells. DNA fragments encoding BR/HLH/LZ structure of Myc and Myn proteins were cloned in frame into pGEX-2T vec-tor respectively Fusion GST-Myc and GST-Myn synthe-sized in E.coli hosts showed affinity to CACGTG E-boxDNA and subsequently interacted with genomic fragments prepared through whole-genome-PCR. A PCR-assisted procedure which combines protein-DNA interaction and affinity chromatography was designed to enrich Myc/Myn bound DNA. At least two genomic DNA fragments ob- tained exhibit specifical binding capacity to Myc/Myn complex but not to GST alone. Significance of the work and of the technique itself as well as identification of the DNAs are discussed.
文摘Objective： To investigate the mechanism of herb cake-partitioned moxibustion treating ulcerative colitis （UC） from the relationship between expression of p53 and C-myc protein, and morbidity of UC. Methods： Rats model of UC was made with immune methods and local stimulation. Forty SD rats were divided into normal, model, herb cake-partitioned, and mild moxibustion group by a random number table, 10 rats in each group. Hanging moxibustion in the mild moxibustion group was applied to Tianshu （ST 25） and Qihai （CV 6） for 10 rain. Two moxa cones of herb cake-partitioned moxibustion were applied to the same acupoints respectively, in the herb cake-partitioned moxibustion group. Expression of p53 and C-myc protein was measured with immuno- histochemistical method in the colonic tissue of rats with UC. Results： Postive area, strength, and the immunohistochemistry index of the expression of p53 and C-myc protein were found more in the model rats than those in the normal rats （P〈0.01）, whereas less in the herb cake-partitioned moxibustion and mild moxibustion groups than those in the model group （P〈0.01）. Conclusion： p53 and C-myc play important roles in the morbidity and development of UC, and herb cake-partitioned moxibustion could regulate the expression of p53 and C-myc protein in the colonic tissue of UC rats.
