RNA interference has been widely used for gene therapy of various infectious diseases and malignant tumors. However, its poor stability in serum has limited further clinic application. Here, we found that stability of...RNA interference has been widely used for gene therapy of various infectious diseases and malignant tumors. However, its poor stability in serum has limited further clinic application. Here, we found that stability of siRNA in serum enhanced obviously when 3′-terminus of sense strand （siRNA-pS） was conjugated with peptide, while same conjugation at 3′-terminus of antisense strand brought no such effects. And it was also found that only the peptide residue in siRNA-pS could be cut off by RNase A. All these results indicated that nucleases in serum prefer to invade siRNA duplex through the 3′-end of sense strand.展开更多
Cationic lipids have been applied to siRNA delivery for tumor therapeutics. However, the excess positive charges of these nanoplexes may lead to high cytotoxicity and nonnegligible immunogenicity both in vitro and in ...Cationic lipids have been applied to siRNA delivery for tumor therapeutics. However, the excess positive charges of these nanoplexes may lead to high cytotoxicity and nonnegligible immunogenicity both in vitro and in vivo, which limited the applications of gene drugs. We constructed multi-component lipoplex to delivery 3＇,3＂-bis-peptide-siRNA conjugate （pp-siRNA） by the treatment of melanoma. Based on the previous studies that the gemini lipid （CLD） encapsulated pp-siRNA, a novel neutral cytosin-l-yl- lipid （DNCA） was considered to replace a certain ration of CLD by hydrogen bonds and ~t-n stacking for reducing the cytotoxicity. It similarly retained in both the loading efficiency and targeted mRNA inhibition when DNCA was accounted for 40% in the lipoplex, with lower toxicity. Moreover, CLD/DNCA/pp-siRNA nanoplex could be uptake in A375 cells and internalized mainly by macropinocytosis and caveolin-mediated endocytosis. Besides, 90% CLD/DNCA/pp-siRNA nanoplexes presented the highest efficient knockdown for the mutant B-RAF mRNA （-80%）. All the results demonstrated that the mixed cationic and neutral lipids could efficiently realize the delivery of pp-siRNA and had potential application for cancer therapy.展开更多
基金Ministry of Science and Technology of China(Grant No.2012CB720604)National Natural Science Foundation of China(Grant No.20932001)
文摘RNA interference has been widely used for gene therapy of various infectious diseases and malignant tumors. However, its poor stability in serum has limited further clinic application. Here, we found that stability of siRNA in serum enhanced obviously when 3′-terminus of sense strand （siRNA-pS） was conjugated with peptide, while same conjugation at 3′-terminus of antisense strand brought no such effects. And it was also found that only the peptide residue in siRNA-pS could be cut off by RNase A. All these results indicated that nucleases in serum prefer to invade siRNA duplex through the 3′-end of sense strand.
基金The National Natural Science Foundation of China(Grant No.21778006 and 20932001)the Ministry of Science and Technology of China(Grant No.2012AA022501)
文摘Cationic lipids have been applied to siRNA delivery for tumor therapeutics. However, the excess positive charges of these nanoplexes may lead to high cytotoxicity and nonnegligible immunogenicity both in vitro and in vivo, which limited the applications of gene drugs. We constructed multi-component lipoplex to delivery 3＇,3＂-bis-peptide-siRNA conjugate （pp-siRNA） by the treatment of melanoma. Based on the previous studies that the gemini lipid （CLD） encapsulated pp-siRNA, a novel neutral cytosin-l-yl- lipid （DNCA） was considered to replace a certain ration of CLD by hydrogen bonds and ~t-n stacking for reducing the cytotoxicity. It similarly retained in both the loading efficiency and targeted mRNA inhibition when DNCA was accounted for 40% in the lipoplex, with lower toxicity. Moreover, CLD/DNCA/pp-siRNA nanoplex could be uptake in A375 cells and internalized mainly by macropinocytosis and caveolin-mediated endocytosis. Besides, 90% CLD/DNCA/pp-siRNA nanoplexes presented the highest efficient knockdown for the mutant B-RAF mRNA （-80%）. All the results demonstrated that the mixed cationic and neutral lipids could efficiently realize the delivery of pp-siRNA and had potential application for cancer therapy.
