DMAKO-05,a novel dimethylation of alkannin oxime derivative,exhibits remarkable anticancer activity as well as excellent cellular selectivity and thus has been considered as a promising antineoplastic agent for colore...DMAKO-05,a novel dimethylation of alkannin oxime derivative,exhibits remarkable anticancer activity as well as excellent cellular selectivity and thus has been considered as a promising antineoplastic agent for colorectal carcinoma and melanoma.However,its potent cytotoxicity is not closely associated with reactive oxygen species（ROS） and bioreductive alkylation.Its specific antitumor target（s） has still remained elusive.To recognize the molecular target（s） of DMAKO-05 and its analogs,four biotinylated DMAKO derivatives were designed and prepared.The biotin moiety was successfully introduced in the molecule through a modified Mitsunobu reaction,which kept its anticancer activity.Moreover,the cellbased investigation demonstrated that replacement of the linker C4 chain with another alkyl chain（C6 or C8） gave rise to the enhancement of cytotoxicity.Among these biotinyl derivatives,both compound 16 and 8c exhibited more potent anticancer activity than DMAKO-05 against MCF-7 cells and were comparatively effective to alkannin toward HCT-15 cells.As expected,they might be thought as ideal chemical probes.Collectively,our present work could provide an available approach for the identification of the potential antineoplastic target（s） of DMAKO derivatives.展开更多
Probes are essential for study of gene expression and regulation. In this study, a method was established to prepare the biotin-labeled probe for 18S rRNA gene of freshwater prawn, Macrobrachium rosenbergii. And the l...Probes are essential for study of gene expression and regulation. In this study, a method was established to prepare the biotin-labeled probe for 18S rRNA gene of freshwater prawn, Macrobrachium rosenbergii. And the labeled method was used to produce a lysozyme gene probe, then applied in analysis of lysozyme gene expression. Primers were designed according to the nucleotide sequences of 18S rRNA of Decapoda in order to isolate the 18S rRNA gene sequences of M. rosenbergii. Total genomic DNA was isolated from hepatopancreas of the freshwater prawn. A specific DNA fragment with desired size was amplified by PCR using the total DNA as templates. The DNA fragment was inserted into pGEM-T Easy vector and sequenced. The result of BLAST and alignment analysis confirmed that the DNA fragment isolated was the 18S rRNA gene of M. rosenbergii, which was 418 nt in length. Biotin-labeled probe of the 18S rRNA was then produced by PCR using the recombinant plasmid as templates. The biotin-21-dTTP and the non-labeled dNTP were added to the PCR reaction system. Ratio of the biotin-21-dTTP and the non-labeled dTTP was 3 to 1. The yield of the labeled probe is 300 ng·μL-1. The detection limit of the probe is 60 pg. A biotin-labeled probe of lysozyme gene was prepared by the same label method, and the yield of the lysozyme gene probe is 500 ng·μL-1. These biotin-labeled probes were applied in Northern dot blotting analysis of tissue distribution of lysoyzme mRNA of M. rosenbergii. Signals were scanned and quantified by Analysis System of Biology Image. The signal intensity ratio of the lysozyme to 18S rRNA represents the relative expression level of lysozyme mRNA. The results showed that the lysozyme mRNA existed in all the tissues checked, including eye, muscle, gill, hepatopancreas, haemocytes and intestine. But lysoyzme mRNA levels varied among different tissues. The highest level was found in the intestine, and the second was in the hepatopancreas and the lowest was in the muscle. The signal intensities of 18S rRNA among tissues were consistent, which showed that the 18S rRNA gene expressed stably in different tissues and could be used as an internal standard for researches of specific gene expression in prawns.展开更多
基金supported by National Natural Science Foundation of China (No. 81373274)Ph.D. Programs Foundation of Ministry of Education China (No. 20120073110068)Shanghai Biomedical Supporting Funding (No. 15431900600)
文摘DMAKO-05,a novel dimethylation of alkannin oxime derivative,exhibits remarkable anticancer activity as well as excellent cellular selectivity and thus has been considered as a promising antineoplastic agent for colorectal carcinoma and melanoma.However,its potent cytotoxicity is not closely associated with reactive oxygen species（ROS） and bioreductive alkylation.Its specific antitumor target（s） has still remained elusive.To recognize the molecular target（s） of DMAKO-05 and its analogs,four biotinylated DMAKO derivatives were designed and prepared.The biotin moiety was successfully introduced in the molecule through a modified Mitsunobu reaction,which kept its anticancer activity.Moreover,the cellbased investigation demonstrated that replacement of the linker C4 chain with another alkyl chain（C6 or C8） gave rise to the enhancement of cytotoxicity.Among these biotinyl derivatives,both compound 16 and 8c exhibited more potent anticancer activity than DMAKO-05 against MCF-7 cells and were comparatively effective to alkannin toward HCT-15 cells.As expected,they might be thought as ideal chemical probes.Collectively,our present work could provide an available approach for the identification of the potential antineoplastic target（s） of DMAKO derivatives.
文摘Probes are essential for study of gene expression and regulation. In this study, a method was established to prepare the biotin-labeled probe for 18S rRNA gene of freshwater prawn, Macrobrachium rosenbergii. And the labeled method was used to produce a lysozyme gene probe, then applied in analysis of lysozyme gene expression. Primers were designed according to the nucleotide sequences of 18S rRNA of Decapoda in order to isolate the 18S rRNA gene sequences of M. rosenbergii. Total genomic DNA was isolated from hepatopancreas of the freshwater prawn. A specific DNA fragment with desired size was amplified by PCR using the total DNA as templates. The DNA fragment was inserted into pGEM-T Easy vector and sequenced. The result of BLAST and alignment analysis confirmed that the DNA fragment isolated was the 18S rRNA gene of M. rosenbergii, which was 418 nt in length. Biotin-labeled probe of the 18S rRNA was then produced by PCR using the recombinant plasmid as templates. The biotin-21-dTTP and the non-labeled dNTP were added to the PCR reaction system. Ratio of the biotin-21-dTTP and the non-labeled dTTP was 3 to 1. The yield of the labeled probe is 300 ng·μL-1. The detection limit of the probe is 60 pg. A biotin-labeled probe of lysozyme gene was prepared by the same label method, and the yield of the lysozyme gene probe is 500 ng·μL-1. These biotin-labeled probes were applied in Northern dot blotting analysis of tissue distribution of lysoyzme mRNA of M. rosenbergii. Signals were scanned and quantified by Analysis System of Biology Image. The signal intensity ratio of the lysozyme to 18S rRNA represents the relative expression level of lysozyme mRNA. The results showed that the lysozyme mRNA existed in all the tissues checked, including eye, muscle, gill, hepatopancreas, haemocytes and intestine. But lysoyzme mRNA levels varied among different tissues. The highest level was found in the intestine, and the second was in the hepatopancreas and the lowest was in the muscle. The signal intensities of 18S rRNA among tissues were consistent, which showed that the 18S rRNA gene expressed stably in different tissues and could be used as an internal standard for researches of specific gene expression in prawns.
