BACKGROUND Esophageal cancer is one of the most common cancers around the world, and it has high incidence and mortality rates. The conventional therapy for esophageal cancer is radiotherapy, although its effect is hi...BACKGROUND Esophageal cancer is one of the most common cancers around the world, and it has high incidence and mortality rates. The conventional therapy for esophageal cancer is radiotherapy, although its effect is highly limited by the resistance of esophageal cancer cells. Thus, strong radiosensitizers can be very crucial during radiotherapy against esophageal cancer. Brucea javanica oil emulsion (BJOE) is a widely used drug against various cancers, such as liver, colon, and ovarian cancer. However, its anti-cancer effect and mechanism and the use of BJOE as a radiosensitizer have not been explored in esophageal cancer. AIM To evaluate the anti-cancer effect and mechanism of BJOE and explore the potential use of BJOE as a radiosensitizer during radiotherapy. METHODS The inhibitory effect of BJOE and its enhancement function with radiation on cell viability were examined with the calculated half-maximal effective concentration and half-maximal lethal concentration. The influence of BJOE on cell migration and invasion were measured with EC109 and JAR cells by wound-healing and transwell assay. Clonogenesis and apoptotic rate, which was measured by Hoechst staining, were investigated to confirm its enhancement function with radiation. To investigate the molecular pathway underlying the effect of BJOE, the expressions of several apoptosis- and cycle-related proteins was detected by western blotting.cell lines more than normal cell lines, and it markedly reduced migration and invasion in esophageal cancer cells (EC109 and JAR). Moreover, it promoted cell apoptosis and enhanced the effect of radiotherapy against esophageal cancerous cells. In the viability test, the values of half-maximal effective concentration and half-maximal lethal concentration were reduced. Compared to the control, only around 1/5 colonies formed when using BJOE and radiation together in the clonogenic assay. The apoptotic rate in EC109 was obviously promoted when BJOE was added during radiotherapy. Our study suggests that the expression of the展开更多
Dbait is a small double-stranded DNA molecule that has been utilized as a radiosensitizer to enhance the sensitivity of glioma to radiotherapy(RT). However, there is no effective drug delivery system to effectively ov...Dbait is a small double-stranded DNA molecule that has been utilized as a radiosensitizer to enhance the sensitivity of glioma to radiotherapy(RT). However, there is no effective drug delivery system to effectively overcome the blood–brain barrier(BBB). The aim of this study was to develop a gene delivery system by using the BBB and glioma dual-targeting and microenvironment-responsive micelles(ch-Kn(s-s)R8-An) to deliver Dbait into glioma for RT. Angiopep-2 can target the low-density lipoprotein receptor-related protein-1(LRP1) that is overexpressed on brain capillary endothelial cells(BCECs) and glioma cells. In particular, due to upregulated matrix metalloproteinase 2(MMP-2) in the tumor microenvironment, we utilized MMP-2-responsive peptides as the enzymatically degradable linkers to conjugate angiopep-2. The results showed that ch-Kn(s-s)R8-An micelles maintained a reasonable size(80–160 nm) with a moderate distribution and a decreased mean diameter from the cross-linking as well as exhibited low critical micelle concentration(CMC) with positive surface charge, ranging from 15 to40 mV. The ch-K5(s-s)R8-An/pEGFP showed high gene transfection efficiency in vitro, improved uptake in glioma cells and good biocompatibility in vitro and in vivo. In addition, the combination of ch-K5(s-s)R8-An/Dbait with RT significantly inhibited the growth of U251 cells in vitro. Thus, ch-K5(s-s)R8-An/Dbait may prove to be a promising gene delivery system to target glioma and enhance the efficacy of RT on U251 cells.展开更多
Local hypoxia in solid tumors often results in resistance to radiotherapy (RT), in which oxygen is an essential element for enhancing DNA damage caused by ionizing radiation. Herein, we developed gold@manganese diox...Local hypoxia in solid tumors often results in resistance to radiotherapy (RT), in which oxygen is an essential element for enhancing DNA damage caused by ionizing radiation. Herein, we developed gold@manganese dioxide (Au@MnO2) core-shell nanoparticles with a polyethylene glycol (PEG) coating as a novel radiosensitizing agent to improve RT efficacy during cancer treatment. In this Au@MnO2 nanostructure, while the gold core is a well-known RT sensitizer that interacts with X-rays to produce charged particles for improved cancer killing under RT, the MnO2 shell may trigger the decomposition of endogenous H2O2 in the tumor microenvironment to generate oxygen and overcome hypoxiaassociated RT resistance. As demonstrated by both in vitro and in vivo experiments, Au@MnO2-PEG nanoparticles acted as effective radiosensitizers to remarkably enhance cancer treatment efficacy during RT. Moreover, no obvious side effects of Au@MnO2-PEG were observed in mice. Therefore, our work presents a new type of radiosensitizer with potential for enhanced RT treatment of hypoxic tumors.展开更多
AIM: To investigate the feasibility and efficacy of the combination of S-1 with gemcitabine followed by oral S-1 with concurrent radiotherapy (intensity modulated radiotherapy, IMRT) and maintenance therapy with S-1 f...AIM: To investigate the feasibility and efficacy of the combination of S-1 with gemcitabine followed by oral S-1 with concurrent radiotherapy (intensity modulated radiotherapy, IMRT) and maintenance therapy with S-1 for locally advanced pancreatic cancer.展开更多
文摘BACKGROUND Esophageal cancer is one of the most common cancers around the world, and it has high incidence and mortality rates. The conventional therapy for esophageal cancer is radiotherapy, although its effect is highly limited by the resistance of esophageal cancer cells. Thus, strong radiosensitizers can be very crucial during radiotherapy against esophageal cancer. Brucea javanica oil emulsion (BJOE) is a widely used drug against various cancers, such as liver, colon, and ovarian cancer. However, its anti-cancer effect and mechanism and the use of BJOE as a radiosensitizer have not been explored in esophageal cancer. AIM To evaluate the anti-cancer effect and mechanism of BJOE and explore the potential use of BJOE as a radiosensitizer during radiotherapy. METHODS The inhibitory effect of BJOE and its enhancement function with radiation on cell viability were examined with the calculated half-maximal effective concentration and half-maximal lethal concentration. The influence of BJOE on cell migration and invasion were measured with EC109 and JAR cells by wound-healing and transwell assay. Clonogenesis and apoptotic rate, which was measured by Hoechst staining, were investigated to confirm its enhancement function with radiation. To investigate the molecular pathway underlying the effect of BJOE, the expressions of several apoptosis- and cycle-related proteins was detected by western blotting.cell lines more than normal cell lines, and it markedly reduced migration and invasion in esophageal cancer cells (EC109 and JAR). Moreover, it promoted cell apoptosis and enhanced the effect of radiotherapy against esophageal cancerous cells. In the viability test, the values of half-maximal effective concentration and half-maximal lethal concentration were reduced. Compared to the control, only around 1/5 colonies formed when using BJOE and radiation together in the clonogenic assay. The apoptotic rate in EC109 was obviously promoted when BJOE was added during radiotherapy. Our study suggests that the expression of the
基金the financial support received from the National Natural Science Foundation of China(No.81472349,81302714and 81201809,China)the Natural Science Foundation of Shanghai(No.14ZR1433300,China)+3 种基金the Interdisciplinary Program of Shanghai Jiao Tong University(No.0507N17014,China)the Innovation Program of Shanghai Municipal Education Commission(No.15ZZ041,China)Natural Science Foundation of Zhejiang Province(No.LQ12H30005,China)the Public Welfare Technology Application Research Project(No.LGF18H160034,China)
文摘Dbait is a small double-stranded DNA molecule that has been utilized as a radiosensitizer to enhance the sensitivity of glioma to radiotherapy(RT). However, there is no effective drug delivery system to effectively overcome the blood–brain barrier(BBB). The aim of this study was to develop a gene delivery system by using the BBB and glioma dual-targeting and microenvironment-responsive micelles(ch-Kn(s-s)R8-An) to deliver Dbait into glioma for RT. Angiopep-2 can target the low-density lipoprotein receptor-related protein-1(LRP1) that is overexpressed on brain capillary endothelial cells(BCECs) and glioma cells. In particular, due to upregulated matrix metalloproteinase 2(MMP-2) in the tumor microenvironment, we utilized MMP-2-responsive peptides as the enzymatically degradable linkers to conjugate angiopep-2. The results showed that ch-Kn(s-s)R8-An micelles maintained a reasonable size(80–160 nm) with a moderate distribution and a decreased mean diameter from the cross-linking as well as exhibited low critical micelle concentration(CMC) with positive surface charge, ranging from 15 to40 mV. The ch-K5(s-s)R8-An/pEGFP showed high gene transfection efficiency in vitro, improved uptake in glioma cells and good biocompatibility in vitro and in vivo. In addition, the combination of ch-K5(s-s)R8-An/Dbait with RT significantly inhibited the growth of U251 cells in vitro. Thus, ch-K5(s-s)R8-An/Dbait may prove to be a promising gene delivery system to target glioma and enhance the efficacy of RT on U251 cells.
基金This work was partially supported by the National Basic Research Program of China (973 Program, Nos. 2014CB931900 and 2012CB932600), National Natural Science Foundation of China (Nos. 81471716 and 31400861), the National Natural Science Foundation of Jiangsu Province (No. BK20140320), and a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).
文摘Local hypoxia in solid tumors often results in resistance to radiotherapy (RT), in which oxygen is an essential element for enhancing DNA damage caused by ionizing radiation. Herein, we developed gold@manganese dioxide (Au@MnO2) core-shell nanoparticles with a polyethylene glycol (PEG) coating as a novel radiosensitizing agent to improve RT efficacy during cancer treatment. In this Au@MnO2 nanostructure, while the gold core is a well-known RT sensitizer that interacts with X-rays to produce charged particles for improved cancer killing under RT, the MnO2 shell may trigger the decomposition of endogenous H2O2 in the tumor microenvironment to generate oxygen and overcome hypoxiaassociated RT resistance. As demonstrated by both in vitro and in vivo experiments, Au@MnO2-PEG nanoparticles acted as effective radiosensitizers to remarkably enhance cancer treatment efficacy during RT. Moreover, no obvious side effects of Au@MnO2-PEG were observed in mice. Therefore, our work presents a new type of radiosensitizer with potential for enhanced RT treatment of hypoxic tumors.
文摘AIM: To investigate the feasibility and efficacy of the combination of S-1 with gemcitabine followed by oral S-1 with concurrent radiotherapy (intensity modulated radiotherapy, IMRT) and maintenance therapy with S-1 for locally advanced pancreatic cancer.