目的建立唑来膦酸与多柔比星包封率的测定方法,以包封率为指标优化唑来膦酸与多柔比星共载脂质体的处方及制备工艺,以期获得包封率高、稳定性好的制剂。方法将唑来膦酸配制成铵溶液作为水化介质,使用改良乙醇注入法制备唑来膦酸脂质体,...目的建立唑来膦酸与多柔比星包封率的测定方法,以包封率为指标优化唑来膦酸与多柔比星共载脂质体的处方及制备工艺,以期获得包封率高、稳定性好的制剂。方法将唑来膦酸配制成铵溶液作为水化介质,使用改良乙醇注入法制备唑来膦酸脂质体,在此基础上通过铵梯度法主动包载多柔比星以实现两种药物在脂质体中的共载。分别采用G-150葡聚糖凝胶微柱-高效液相色谱法与阳离子交换纤维微柱-紫外可见分光光度法测定唑来膦酸与多柔比星的包封率,通过对脂质体外水相中唑来膦酸的去除及对水化介质中阴离子浓度的考察,优化脂质体的处方与制备工艺。结果最优处方与工艺下制备的共载脂质体粒径约为110 nm,Zeta电位为-0.87 m V,其中唑来膦酸的包封率为6.5%,多柔比星的包封率大于90%。脂质体于4℃下避光放置60 d,粒径和包封率均无显著性变化,稳定性良好。结论唑来膦酸与多柔比星共载脂质体的包封率较高,稳定性较好。展开更多
The lymphatic system has an important defensive role in the human body. The metastasis of most tumors initially spreads through the surrounding lymphatic tissue and eventually forms lymphatic metastatic tumors; the tu...The lymphatic system has an important defensive role in the human body. The metastasis of most tumors initially spreads through the surrounding lymphatic tissue and eventually forms lymphatic metastatic tumors; the tumor cells may even transfer to other organs to form other types of tumors. Clinically, lymphatic metastatic tumors develop rapidly. Given the limitations of surgical resection and the low effectiveness of radiotherapy and chemotherapy, the treatment of lymphatic metastatic tumors remains a great challenge. Lymph node metastasis may lead to the further spread of tumors and may be predictive of the endpoint event. Under these circumstances, novel and effective lymphatic targeted drug delivery systems have been explored to improve the specificity of anticancer drugs to tumor cells in lymph nodes. In this review, we summarize the principles of lymphatic targeted drug delivery and discuss recent advances in the development of lymphatic targeted carriers.展开更多
Current treatment modalities provide limited improvement in the natural course of lung cancer, and prognosis remains poor. Lung cancer is a malignancy with great molecular heterogeneity. The complexity of the signalin...Current treatment modalities provide limited improvement in the natural course of lung cancer, and prognosis remains poor. Lung cancer is a malignancy with great molecular heterogeneity. The complexity of the signaling process leading to cancer cell proliferation and to the neoplastic phenotype supports the necessity of interfering at different stages to avoid cancer cell resistance to therapy. For this reason, new strategies for the simultaneous inhibition of multiple molecular targets are being pursued.展开更多
Gastrointestinal cancer is one of the highly prevalent malignant diseases worldwide which is a major cause of morbidity and mortality. Gastric cancer is the second leading cause of cancer mortality in the world and it...Gastrointestinal cancer is one of the highly prevalent malignant diseases worldwide which is a major cause of morbidity and mortality. Gastric cancer is the second leading cause of cancer mortality in the world and its management, especially in advanced stages, has evolved relatively little [1]. Colorectal cancer (CRC) remains the third most common ma-lignancy and the third leading cause of cancer death worldwide [2]. The surgical treatment is still the most effective therapy for the gastrointestinal cancer. However, the majority of the patients had lost the opporunity of surgical therapy when it was detected at advanced stage, so to seek means other than surgical treatment of gastrointestinal cancer metastasis and recur-rence also has an important significance. With the deeping research of the molecular biology, molecular targeted therapy has become the hotspot and focus of comprehensive treatment of gastrointestinal cancer which is proposed against the molecular biological targets such as tumor cell growth, apoptosis, cell cycle, invasion and angiogenesis. Molecular targeted therapy can be grouped into six main areas: the epidermal growth factor receptor (EGFR) inhibitors, anti-angiogenic factors, cell cycle inhibitors, apoptosis promoters and matrix metalloproteinase inhibitors, cyclooxygenase inhibitors. The review of the progress are as follows.展开更多
OBJECTIVE: To specifically deliver the therapeutic gene to cancer cells and construct target retroviral vectors by inserting the single-chain variable antibody fragment into the retroviral envelope. METHODS: Single-ch...OBJECTIVE: To specifically deliver the therapeutic gene to cancer cells and construct target retroviral vectors by inserting the single-chain variable antibody fragment into the retroviral envelope. METHODS: Single-chain antibody expression vector pET -20bScfv was constructed. Binding activity of the genetically engineered single-chain variable antibody fragment was verified by enzyme-linked immunosorbent assay (ELISA) and Western blot. At the same time, by means of polymerase chain reaction (PCR)-directed mutagenesis, the appropriate cloning site EcoT22/Sal was generated at the N-terminus of receptor-binding SU domain in the MoMLV env polypeptide. Then the single- chain antibody gene, encoding a functional antibody, was inserted into the cloning site. The Scfv-env fusion gene fragment was subcloned into CMV expression vector. The Lac-Z retrovirus that co-displayed the Scfv-env chimeric protein and wild-type env protein was produced by transfection of Psi 2 cells with retroviral plasmid and the fusion gene expressing plasmid.To confirm the specificity of the recombinant retrovirus, infection assays and competitive inhibition assays were performed. RESULTS: The results of ELISA and Western blot showed that the genetically engineered single-chain variable antibody fragment could bind to the SHG44 cells surface membrane antigen. Virus-binding assay, viral infection and competitive inhibition assays confirmed that the harvested virus efficiently bound to and infected SHG44 cancer cells expressing the relative membrane antigen specially via the recognition of the target antigen. CONCLUSION: These results imply that insertion of Scfv into the retroviral envelope can specifically deliver the interested gene into specific antigen-producing cancer cells.展开更多
In order to enhance the targeted delivery of anticancer drugs by polymeric micelles, folic acid(FA), the ligand of folate receptor(FR) over-expressed in the most cancer cells, modified p H-sensitive polymeric micelles...In order to enhance the targeted delivery of anticancer drugs by polymeric micelles, folic acid(FA), the ligand of folate receptor(FR) over-expressed in the most cancer cells, modified p H-sensitive polymeric micelles were designed and fabricated to encapsulate doxorubicin(DOX) by combination of p H-sensitive amphiphilic polymer poly(2-ethyl-2-oxazoline)-poly(D,L-lactide) with FA-conjugated poly(2-ethyl-2-oxazoline)-poly(D,L-lactide). The prepared micelles were characterized to have about 36 nm in diameter with narrow distribution, well-defined spherical shape observed under TEM and p H-responsive drug release behavior. Moreover, the tumor targeting ability of the FA-modified p H-sensitive polymeric micelles was demonstrated by the cellular uptake, in vitro cytotoxicity to FR-positive KB cells and in vivo real time near-infrared fluorescence imaging in KB tumor-bearing nude mice. The efficient drug delivery by the micelles was ascribed to the synergistic effects of FR-mediated targeting and p H-triggered drug release. In conclusion, the designed FR-targeted p H-sensitive polymeric micelles might be of great potential in tumor targeted delivery of water-insoluble anticancer drugs.展开更多
文摘目的建立唑来膦酸与多柔比星包封率的测定方法,以包封率为指标优化唑来膦酸与多柔比星共载脂质体的处方及制备工艺,以期获得包封率高、稳定性好的制剂。方法将唑来膦酸配制成铵溶液作为水化介质,使用改良乙醇注入法制备唑来膦酸脂质体,在此基础上通过铵梯度法主动包载多柔比星以实现两种药物在脂质体中的共载。分别采用G-150葡聚糖凝胶微柱-高效液相色谱法与阳离子交换纤维微柱-紫外可见分光光度法测定唑来膦酸与多柔比星的包封率,通过对脂质体外水相中唑来膦酸的去除及对水化介质中阴离子浓度的考察,优化脂质体的处方与制备工艺。结果最优处方与工艺下制备的共载脂质体粒径约为110 nm,Zeta电位为-0.87 m V,其中唑来膦酸的包封率为6.5%,多柔比星的包封率大于90%。脂质体于4℃下避光放置60 d,粒径和包封率均无显著性变化,稳定性良好。结论唑来膦酸与多柔比星共载脂质体的包封率较高,稳定性较好。
基金supported by the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20110071130011)the National Science and Technology Major Project (No. 2012ZX09304004)
文摘The lymphatic system has an important defensive role in the human body. The metastasis of most tumors initially spreads through the surrounding lymphatic tissue and eventually forms lymphatic metastatic tumors; the tumor cells may even transfer to other organs to form other types of tumors. Clinically, lymphatic metastatic tumors develop rapidly. Given the limitations of surgical resection and the low effectiveness of radiotherapy and chemotherapy, the treatment of lymphatic metastatic tumors remains a great challenge. Lymph node metastasis may lead to the further spread of tumors and may be predictive of the endpoint event. Under these circumstances, novel and effective lymphatic targeted drug delivery systems have been explored to improve the specificity of anticancer drugs to tumor cells in lymph nodes. In this review, we summarize the principles of lymphatic targeted drug delivery and discuss recent advances in the development of lymphatic targeted carriers.
文摘Current treatment modalities provide limited improvement in the natural course of lung cancer, and prognosis remains poor. Lung cancer is a malignancy with great molecular heterogeneity. The complexity of the signaling process leading to cancer cell proliferation and to the neoplastic phenotype supports the necessity of interfering at different stages to avoid cancer cell resistance to therapy. For this reason, new strategies for the simultaneous inhibition of multiple molecular targets are being pursued.
文摘Gastrointestinal cancer is one of the highly prevalent malignant diseases worldwide which is a major cause of morbidity and mortality. Gastric cancer is the second leading cause of cancer mortality in the world and its management, especially in advanced stages, has evolved relatively little [1]. Colorectal cancer (CRC) remains the third most common ma-lignancy and the third leading cause of cancer death worldwide [2]. The surgical treatment is still the most effective therapy for the gastrointestinal cancer. However, the majority of the patients had lost the opporunity of surgical therapy when it was detected at advanced stage, so to seek means other than surgical treatment of gastrointestinal cancer metastasis and recur-rence also has an important significance. With the deeping research of the molecular biology, molecular targeted therapy has become the hotspot and focus of comprehensive treatment of gastrointestinal cancer which is proposed against the molecular biological targets such as tumor cell growth, apoptosis, cell cycle, invasion and angiogenesis. Molecular targeted therapy can be grouped into six main areas: the epidermal growth factor receptor (EGFR) inhibitors, anti-angiogenic factors, cell cycle inhibitors, apoptosis promoters and matrix metalloproteinase inhibitors, cyclooxygenase inhibitors. The review of the progress are as follows.
文摘OBJECTIVE: To specifically deliver the therapeutic gene to cancer cells and construct target retroviral vectors by inserting the single-chain variable antibody fragment into the retroviral envelope. METHODS: Single-chain antibody expression vector pET -20bScfv was constructed. Binding activity of the genetically engineered single-chain variable antibody fragment was verified by enzyme-linked immunosorbent assay (ELISA) and Western blot. At the same time, by means of polymerase chain reaction (PCR)-directed mutagenesis, the appropriate cloning site EcoT22/Sal was generated at the N-terminus of receptor-binding SU domain in the MoMLV env polypeptide. Then the single- chain antibody gene, encoding a functional antibody, was inserted into the cloning site. The Scfv-env fusion gene fragment was subcloned into CMV expression vector. The Lac-Z retrovirus that co-displayed the Scfv-env chimeric protein and wild-type env protein was produced by transfection of Psi 2 cells with retroviral plasmid and the fusion gene expressing plasmid.To confirm the specificity of the recombinant retrovirus, infection assays and competitive inhibition assays were performed. RESULTS: The results of ELISA and Western blot showed that the genetically engineered single-chain variable antibody fragment could bind to the SHG44 cells surface membrane antigen. Virus-binding assay, viral infection and competitive inhibition assays confirmed that the harvested virus efficiently bound to and infected SHG44 cancer cells expressing the relative membrane antigen specially via the recognition of the target antigen. CONCLUSION: These results imply that insertion of Scfv into the retroviral envelope can specifically deliver the interested gene into specific antigen-producing cancer cells.
基金National Natural Science Foundation of China(Grant No.81673366)。
文摘In order to enhance the targeted delivery of anticancer drugs by polymeric micelles, folic acid(FA), the ligand of folate receptor(FR) over-expressed in the most cancer cells, modified p H-sensitive polymeric micelles were designed and fabricated to encapsulate doxorubicin(DOX) by combination of p H-sensitive amphiphilic polymer poly(2-ethyl-2-oxazoline)-poly(D,L-lactide) with FA-conjugated poly(2-ethyl-2-oxazoline)-poly(D,L-lactide). The prepared micelles were characterized to have about 36 nm in diameter with narrow distribution, well-defined spherical shape observed under TEM and p H-responsive drug release behavior. Moreover, the tumor targeting ability of the FA-modified p H-sensitive polymeric micelles was demonstrated by the cellular uptake, in vitro cytotoxicity to FR-positive KB cells and in vivo real time near-infrared fluorescence imaging in KB tumor-bearing nude mice. The efficient drug delivery by the micelles was ascribed to the synergistic effects of FR-mediated targeting and p H-triggered drug release. In conclusion, the designed FR-targeted p H-sensitive polymeric micelles might be of great potential in tumor targeted delivery of water-insoluble anticancer drugs.
