RESUMO
Enzyme-prodrug therapies have shown unique advantages in efficiency, selectivity, and specificity of in vivo prodrug activation. However, precise spatiotemporal control of both the enzyme and its substrate at the target site, preservation of enzyme activity, and in situ substrate depletion due to low prodrug delivery efficiency continue to be great challenges. Here, we propose a novel core-shell reactor partitioning enzyme and prodrug by ZIF-8, which integrates an enzyme with its substrate and increases the drug loading capacity (DLC) using a prodrug as the building ligand to form a Zn-prodrug shell. Cytochrome P450 (CYP450) is immobilized in ZIF-8, and the antitumor drug dacarbazine (DTIC) is coordinated and deposited in its outer layer with a high DLC of 43.6±0.8 %. With this configuration, a much higher prodrug conversion efficiency of CYP450 (36.5±1.5 %) and lower IC50 value (26.3±2.6â µg/mL) are measured for B16-F10 cells with a higher NADPH concentration than those of L02 cells and HUVECs. With the tumor targeting ability of hyaluronic acid, this core-shell enzyme reactor shows a high tumor suppression rate of 96.6±1.9 % and provides a simple and versatile strategy for enabling in vivo biocatalysis to be more efficient, selective, and safer.
Assuntos
Antineoplásicos , Neoplasias , Pró-Fármacos , Humanos , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , NADP , Antineoplásicos/farmacologia , Dacarbazina , Sistema Enzimático do Citocromo P-450 , Neoplasias/tratamento farmacológicoRESUMO
We examined new Allacta materials from Yunnan and Hainan Province, China, and discovered new species using both morphological and molecular species delimitation (ABGD) methods. Five new species are described: A.bifolium Li & Wang, sp. nov., A.hemiptera Li & Wang, sp. nov., A.lunulara Li & Wang, sp. nov., A.redacta Li & Wang, sp. nov., and A.unicaudata Li & Wang, sp. nov. All five species are placed under the hamifera species group. An updated key and checklist of Allacta species from China are provided.
RESUMO
AIM: To investigate the inhibitory efficacy of (125)I-labeled anti-basic fibroblast growth factor (bFGF) monoclonal antibody (mAb) in hepatocellular carcinoma (HCC). METHODS: bFGF mAb was prepared by using the 1G9B9 hybridoma cell line with hybridization technology and extracted from ascites fluid through a Protein G Sepharose affinity column. After labeling with (125)I through the chloramine-T method, bFGF mAb was further purified by a Sephadex G-25 column. Gamma radiation counter GC-1200 detected radioactivity of (125)I-bFGF mAb. The murine H22 HCC xenograft model was established and randomized to interventions with control (phosphate-buffered saline), (125)I-bFGF mAb, (125)I plus bFGF mAb, bFGF mAb, or (125)I. The ratios of tumor inhibition were then calculated. Expression of bFGF, fibroblast growth factor receptor (FGFR), platelet-derived growth factor, and vascular endothelial growth factor (VEGF) mRNA was determined by quantitative reverse transcriptase real-time polymerase chain reaction. RESULTS: The purified bFGF mAb solution was 8.145 mg/mL with a titer of 1:2560000 and was stored at -20â °C. After coupling, (125)I-bFGF mAb was used at a 1: 1280000 dilution, stored at 4â °C, and its specific radioactivity was 37 MBq/mg. The corresponding tumor weight in the control, (125)I, bFGF mAb, (125)I plus bFGF mAb, and (125)I-bFGF mAb groups was 1.88 ± 0.25, 1.625 ± 0.21, 1.5 ± 0.18, 1.41 ± 0.16, and 0.98 ± 0.11 g, respectively. The tumor inhibition ratio in the (125)I, bFGF mAb, (125)I plus bFGF mAb, and (125)I-bFGF mAb groups was 13.6%, 20.2%, 25.1%, and 47.9%, respectively. Growth of HCC xenografts was inhibited significantly more in the (125)I-bFGF mAb group than in the other groups (P < 0.05). Expression of bFGF and FGFR mRNA in the (125)I-bFGF mAb group was significantly decreased in comparison with other groups (P < 0.05). Groups under interventions revealed increased expression of VEGF mRNA (except for (125)I group) compared with the control group. CONCLUSION: (125)I-bFGF mAb inhibits growth of HCC xenografts. The coupling effect of (125)I-bFGF mAb is more effective than the concomitant use of (125)I and bFGF mAb.