BACKGROUND Photodynamic therapy(PDT)is a minimally invasive form of cancer therapy,and the development of a novel photosensitizer(PS)with optimal properties is important for enhancing PDT efficacy.Folate receptor(FR)m...BACKGROUND Photodynamic therapy(PDT)is a minimally invasive form of cancer therapy,and the development of a novel photosensitizer(PS)with optimal properties is important for enhancing PDT efficacy.Folate receptor(FR)membrane protein is frequently overexpressed in 40%of human cancer and a good candidate for tumor-specific targeting.Specific active targeting of PS to FR can be achieved by conjugation with the folate moiety.A folate-linked,near-infrared(NIR)-sensitive probe,folate-Si-rhodamine-1(FolateSiR-1),was previously developed and is expected to be applicable to NIR-PDT.AIM To investigate the therapeutic efficacy of NIR-PDT induced by FolateSiR-1,a FRtargeted PS,in preclinical cancer models.METHODS FolateSiR-1 was developed by conjugating a folate moiety to the Si-rhodamine derivative through a negatively charged tripeptide linker.FR expression in the designated cell lines was examined by western blotting(WB).The selective binding of FolateSiR-1 to FR was confirmed in FR overexpressing KB cells(FR+)and tumors by fluorescence microscopy and in vivo fluorescence imaging.Low FR expressing OVCAR-3 and A4 cell lines were used as negative controls(FR-).The NIR light(635±3 nm)-induced phototoxic effect of FolateSiR-1 was evaluated by cell viability imaging assays.The time-dependent distribution of FolateSiR-1 and its specific accumulation in KB tumors was determined using in vivo longitudinal fluorescence imaging.The PDT effect of FolateSiR-1 was evaluated in KB tumor bearing mice divided into four experimental groups:(1)FolateSiR-1(100μmol/L)alone;(2)FolateSiR-1(100μmol/L)followed by NIR irradiation(50 J/cm2);(3)NIR irradiation(50 J/cm2)alone;and(4)no treatment.Tumor volume measurement and immunohistochemical(IHC)and histological examinations of the tumors were performed to analyze the effect of PDT.RESULTS High FR expression was observed in the KB cells by WB,but not in the OVCAR-3 and A4 cells.Substantial FR-specific binding of FolateSiR-1 was observed by in vitro and in vivo fluorescence imaging.Cell viability imaging assays showed that NIR-PDT induced cell death in KB cells.In vivo longitudinal fluorescence imaging showed rapid peak accumulation of FolateSiR-1 in the KB tumors 2 h after injection.In vivo PDT conducted at this time point caused tumor growth delay.The relative tumor volumes in the PDT group were significantly reduced compared to those in the other groups[5.81±1.74(NIR-PDT)vs 12.24±2.48(Folate-SiR-1),vs 11.84±3.67(IR),vs 12.98±2.78(Untreated),at Day 16,P<0.05].IHC analysis revealed reduced proliferation marker Ki-67-positive cells in the PDT treated tumors,and hematoxylin-eosin staining revealed features of necrotic-and apoptotic cell death.CONCLUSION FolateSiR-1 has potential for use in PDT,and FR-targeted NIR-PDT may open a new effective strategy for the treatment of FR-overexpressing tumors.展开更多
Autism spectrum disorder(ASD)is a serious neurodevelopmental disorder,the etiology and mechanism of which are not yet clear.Studies have shown that folate deficiency can lead to abnormalities in the de-velopment of th...Autism spectrum disorder(ASD)is a serious neurodevelopmental disorder,the etiology and mechanism of which are not yet clear.Studies have shown that folate deficiency can lead to abnormalities in the de-velopment of the central nervous system.Patients with autism spectrum disorders develop folate-alpha recep-tor autoantibodies.Folate-alpha receptor autoantibodies block folate transport,leading to a deficiency of folate in nerve tissues.Folate is effective in treating patients with folate-alpha receptor autoantibodies.展开更多
Objective：Human pancreatic cancer is one of the most common clinical malignancies.The effect of comprehensive treatment based on surgery is general.The effects of chemotherapy were not obvious mainly because of lack ...Objective：Human pancreatic cancer is one of the most common clinical malignancies.The effect of comprehensive treatment based on surgery is general.The effects of chemotherapy were not obvious mainly because of lack of targeting and chemoresistance in pancreatic cancer.This study aimed to investigate the effects of folate receptor （FR）-mediated gemcitabine FA-Chi-Gem nanoparticles with a core-shell structure by electrostatic spray on pancreatic cancer.Methods：In this study,the levels of expression of FR in six human pancreatic cancer cell lines were studied by immunohistochemical analysis.The uptake rate of isothiocyanate-labeled FA-Chi nanoparticles in FR high expression cell line COLO357 was assessed by fluorescence microscope and the inhibition rate of FA-Chi-Gem nanoparticles on COLO357 cells was evaluated by MTT assay.Moreover,the biodistribution of PEG-FA-ICGDER02-Chi in the orthotopic pancreatic tumor model was observed using near-infrared imaging and the human pancreatic cancer orthotopic xenografts were treated with different nanoparticles and normal saline control.Results：The expression of FR in COLO357 was the highest among the six pancreatic cancer cell lines.The FR mainly distributed on cell membrane and fewer in the cytoplasm in pancreatic cancer.Moreover,the absorption rate of the FA-Chi-Gem nanoparticles was more than the Chi nanoparticles without FA modified.The proliferation of COLO357 was significantly inhibited by FA-Chi-Gem nanoparticles.The PEG-FA-ICGDER02-Chi nanoparticles were enriched in tumor tissue in human pancreatic cancer xenografts,while non-targeted nanoparticles were mainly in normal liver tissue.PEG-FA-Gem-Chi significantly inhibited the growth of human pancreatic cancer xenografts （PEG-FA-Gem-Chi vs.Gem,t=22.950,P=0.000）.Conclusions：PEG-FA-FITC-Chi nanoparticles might be an effective targeted drug for treating human FR-positive pancreatic cancer.展开更多
Almost all cells are easily killed by exposure to potent oxidants. Indeed, major pathogen defense mechanisms in both animal and plant kingdoms involve production of an oxidative burst, where host defense cells show an...Almost all cells are easily killed by exposure to potent oxidants. Indeed, major pathogen defense mechanisms in both animal and plant kingdoms involve production of an oxidative burst, where host defense cells show an invading pathogen with reactive oxygen species (ROS). Although cancer cells can be similarly killed by ROS, development of oxidant-producing chemotherapies has been limited by their inherent nonspecificity and potential toxicity to healthy cells. In this paper, we describe the targeting of an ROS-generating molecule selectively to tumor cells using folate as the tumor-targeting ligand. For this purpose, we exploit the ability of 9,10-phenanthraquinone (PHQ) to enhance the continuous generation of H<sub>2</sub>O<sub>2</sub> in the presence of ascorbic acid to establish a con-stitutive source of ROS within the tumor mass. We report here that incubation of folate receptor-expressing KB cells in culture with folate-PHQ plus ascorbate results in the death of the cancer cells with an IC<sub>50</sub> of ~10 nM (folate-PHQ). We also demonstrate that a cleavable spacer linking folate to PHQ is significantly inferior to a noncleavable spacer, in contrast to most other folate-targeted therapeutic agents. Unfortunately, no evidence for folate-PHQ mediated tumor regression in murine tumor models is obtained, suggesting that unanticipated impediments to generation of cytotoxic quantities of ROS in vivo are encountered. Possible mechanisms and potential solutions to these unanticipated results are offered.展开更多
To assess targeting of an epothilone folate conjugate(BMS-753493) to the folate receptor(FR)-overexpressed tumor in mice bearing both FRt and FR– tumors,a series of experiments were conducted by quantitative whole-bo...To assess targeting of an epothilone folate conjugate(BMS-753493) to the folate receptor(FR)-overexpressed tumor in mice bearing both FRt and FR– tumors,a series of experiments were conducted by quantitative whole-body autoradiography(QWBA) and LC–MS/MS following i.v.administration of BMS-753493 or its active moiety,BMS-748285 in mice bearing FRt(98M109) and FR–(M109) tumors.QWBA showed [3H]BMS-753493–derived radioactivity was extensively distributed to various tissues.The FR over-expressing 98M109 tumors showed consistently higher level of radioactivity than FR-negative tumors(i.e.,M109 tumors) up to 48 h post dose of [3H]BMS-753493,despite the magnitude of difference between the tumors is relatively small(generally 3 5-fold).The radioactivity level in 98M109 tumors was 2 12-fold of normal tissues except intestine/content at 48 h post dose.No selective radioactivity uptake into 98M109 tumors over M109 or normal tissues was observed after i.v.administration of the active epothilone,[3H]BMS-748285.LC–MS/MS measurements demonstrated that the concentrations of BMS-748285,presumably from hydrolysis of the folate conjugate,in 98M109 tumors were greater than those in M109 tumors after i.v.administration of BMS-753493(2–3-fold) whereas no differential uptake in the tumors following BMS-748285 administration.Those data were consistent with radioactivity determinations.Those results demonstrated that the folate conjugation in BMS-753493 enabled moderately preferential distribution of the active epothilone to FR overexpressing 98M109 tumors,thereby supporting targeted delivery of cytotoxics through the folate receptor.展开更多
Invasive nonfunctional pituitary adenomas （NFPAs） are difficult to completely resect and often develop tumor recurrence after initial surgery. Currently, no medications are clinically effective in the control of NFP...Invasive nonfunctional pituitary adenomas （NFPAs） are difficult to completely resect and often develop tumor recurrence after initial surgery. Currently, no medications are clinically effective in the control of NFPA. Although radiation therapy and radiosurgery are useful to prevent tumor regrowth, they are frequently withheld because of severe complications. Boron neutron capture therapy （BNCT） is a binary radiotherapy that selectively and maximally damages tumor cells without harming the surrounding normal tissue. Folate receptor （FR）-targeted boron-10 containing carbon nanoparticles is a novel boron delivery agent that can be selectively taken up by FR-expressing cells via FR-mediated endocytosis. In this study, FR-targeted boron-10 containing carbon nanoparticles were selectively taken up by NFPAs cells expressing FR but not other types of non-FR expressing pituitary adenomas. After incubation with boron-10 containing carbon nanoparticles and following irradiation with thermal neutrons, the cell viability of NFPAs was significantly decreased, while apoptotic cells were simultaneously increased. However, cells administered the same dose of FR-targeted boron-10 containing carbon nanoparticles without neutron irradiation or received the same neutron irradiation alone did not show significant decrease in cell viability or increase in apoptotic cells. The expression of Bcl-2 was down-regulated and the expression of Bax was up-regulated in NFPAs after treatment with FR-mediated BNCT. In conclusion, FR-targeted boron-10 containing carbon nanoparticles may be an ideal delivery system of boron to NFPAs ceils for BNCT. Furthermore, our study also provides a novel insight into therapeutic strategies for invasive NFPA refractory to conventional therapy, while exploring these new applications of BNCT for tumors, especially benign tumors.展开更多
Vulnerable atherosclerotic plaques are responsible for most cardiovascular diseases(CVDs).Folate receptor(FR)positive activated macrophages were thought to be a prominent component in the development of vulnerable pla...Vulnerable atherosclerotic plaques are responsible for most cardiovascular diseases(CVDs).Folate receptor(FR)positive activated macrophages were thought to be a prominent component in the development of vulnerable plaque.The objective of this study is to develop folate conjugated two-dimensional(2D)Pd@Au nanomaterials(Pd@Au-PEG-FA)for targeted multimodal imaging of the FRs in advanced atherosclerotic plaques.Pharmacokinetic and imaging studies(single photon emission computed tomography(SPECT),computed tomography(CT)and photoacoustic(PA)imaging)were performed to confirm the prolonged blood half-life and enrichment of radioactivity in atherosclerotic plaques.Strong signals were detected in vivo with SPECT,CT and PA imaging in heavy atherosclerotic plaques,which were significantly higher than those of the normal aortas after injection of Pd@Au-PEG-FA.Blocking studies with preinjection of excess FA could effectively reduce the targeting ability of Pd@Au-PEG-FA in atherosclerotic plaques,further demonstrating the specific binding of Pd@Au-PEG-FA for plaque lesions.Histopathological characterization revealed that the signal of probe was in accordance with the high-risk plaques.In summary,the Pd@Au-PEG-FA has favorable pharmacokinetic properties and provides a valuable approach for detecting high-risk plaques in the presence of FRs in atherosclerotic plaques.展开更多
文摘BACKGROUND Photodynamic therapy(PDT)is a minimally invasive form of cancer therapy,and the development of a novel photosensitizer(PS)with optimal properties is important for enhancing PDT efficacy.Folate receptor(FR)membrane protein is frequently overexpressed in 40%of human cancer and a good candidate for tumor-specific targeting.Specific active targeting of PS to FR can be achieved by conjugation with the folate moiety.A folate-linked,near-infrared(NIR)-sensitive probe,folate-Si-rhodamine-1(FolateSiR-1),was previously developed and is expected to be applicable to NIR-PDT.AIM To investigate the therapeutic efficacy of NIR-PDT induced by FolateSiR-1,a FRtargeted PS,in preclinical cancer models.METHODS FolateSiR-1 was developed by conjugating a folate moiety to the Si-rhodamine derivative through a negatively charged tripeptide linker.FR expression in the designated cell lines was examined by western blotting(WB).The selective binding of FolateSiR-1 to FR was confirmed in FR overexpressing KB cells(FR+)and tumors by fluorescence microscopy and in vivo fluorescence imaging.Low FR expressing OVCAR-3 and A4 cell lines were used as negative controls(FR-).The NIR light(635±3 nm)-induced phototoxic effect of FolateSiR-1 was evaluated by cell viability imaging assays.The time-dependent distribution of FolateSiR-1 and its specific accumulation in KB tumors was determined using in vivo longitudinal fluorescence imaging.The PDT effect of FolateSiR-1 was evaluated in KB tumor bearing mice divided into four experimental groups:(1)FolateSiR-1(100μmol/L)alone;(2)FolateSiR-1(100μmol/L)followed by NIR irradiation(50 J/cm2);(3)NIR irradiation(50 J/cm2)alone;and(4)no treatment.Tumor volume measurement and immunohistochemical(IHC)and histological examinations of the tumors were performed to analyze the effect of PDT.RESULTS High FR expression was observed in the KB cells by WB,but not in the OVCAR-3 and A4 cells.Substantial FR-specific binding of FolateSiR-1 was observed by in vitro and in vivo fluorescence imaging.Cell viability imaging assays showed that NIR-PDT induced cell death in KB cells.In vivo longitudinal fluorescence imaging showed rapid peak accumulation of FolateSiR-1 in the KB tumors 2 h after injection.In vivo PDT conducted at this time point caused tumor growth delay.The relative tumor volumes in the PDT group were significantly reduced compared to those in the other groups[5.81±1.74(NIR-PDT)vs 12.24±2.48(Folate-SiR-1),vs 11.84±3.67(IR),vs 12.98±2.78(Untreated),at Day 16,P<0.05].IHC analysis revealed reduced proliferation marker Ki-67-positive cells in the PDT treated tumors,and hematoxylin-eosin staining revealed features of necrotic-and apoptotic cell death.CONCLUSION FolateSiR-1 has potential for use in PDT,and FR-targeted NIR-PDT may open a new effective strategy for the treatment of FR-overexpressing tumors.
基金Yunnan Provincial Department of Education Scien-tific Research Fund Project(K13225116).
文摘Autism spectrum disorder(ASD)is a serious neurodevelopmental disorder,the etiology and mechanism of which are not yet clear.Studies have shown that folate deficiency can lead to abnormalities in the de-velopment of the central nervous system.Patients with autism spectrum disorders develop folate-alpha recep-tor autoantibodies.Folate-alpha receptor autoantibodies block folate transport,leading to a deficiency of folate in nerve tissues.Folate is effective in treating patients with folate-alpha receptor autoantibodies.
基金supported by the National Natural Science Foundation of China(No.81071967 and 30872500)the Natural Science Foundation of Jiangsu province(Project No:BK2010242)
文摘Objective：Human pancreatic cancer is one of the most common clinical malignancies.The effect of comprehensive treatment based on surgery is general.The effects of chemotherapy were not obvious mainly because of lack of targeting and chemoresistance in pancreatic cancer.This study aimed to investigate the effects of folate receptor （FR）-mediated gemcitabine FA-Chi-Gem nanoparticles with a core-shell structure by electrostatic spray on pancreatic cancer.Methods：In this study,the levels of expression of FR in six human pancreatic cancer cell lines were studied by immunohistochemical analysis.The uptake rate of isothiocyanate-labeled FA-Chi nanoparticles in FR high expression cell line COLO357 was assessed by fluorescence microscope and the inhibition rate of FA-Chi-Gem nanoparticles on COLO357 cells was evaluated by MTT assay.Moreover,the biodistribution of PEG-FA-ICGDER02-Chi in the orthotopic pancreatic tumor model was observed using near-infrared imaging and the human pancreatic cancer orthotopic xenografts were treated with different nanoparticles and normal saline control.Results：The expression of FR in COLO357 was the highest among the six pancreatic cancer cell lines.The FR mainly distributed on cell membrane and fewer in the cytoplasm in pancreatic cancer.Moreover,the absorption rate of the FA-Chi-Gem nanoparticles was more than the Chi nanoparticles without FA modified.The proliferation of COLO357 was significantly inhibited by FA-Chi-Gem nanoparticles.The PEG-FA-ICGDER02-Chi nanoparticles were enriched in tumor tissue in human pancreatic cancer xenografts,while non-targeted nanoparticles were mainly in normal liver tissue.PEG-FA-Gem-Chi significantly inhibited the growth of human pancreatic cancer xenografts （PEG-FA-Gem-Chi vs.Gem,t=22.950,P=0.000）.Conclusions：PEG-FA-FITC-Chi nanoparticles might be an effective targeted drug for treating human FR-positive pancreatic cancer.
文摘Almost all cells are easily killed by exposure to potent oxidants. Indeed, major pathogen defense mechanisms in both animal and plant kingdoms involve production of an oxidative burst, where host defense cells show an invading pathogen with reactive oxygen species (ROS). Although cancer cells can be similarly killed by ROS, development of oxidant-producing chemotherapies has been limited by their inherent nonspecificity and potential toxicity to healthy cells. In this paper, we describe the targeting of an ROS-generating molecule selectively to tumor cells using folate as the tumor-targeting ligand. For this purpose, we exploit the ability of 9,10-phenanthraquinone (PHQ) to enhance the continuous generation of H<sub>2</sub>O<sub>2</sub> in the presence of ascorbic acid to establish a con-stitutive source of ROS within the tumor mass. We report here that incubation of folate receptor-expressing KB cells in culture with folate-PHQ plus ascorbate results in the death of the cancer cells with an IC<sub>50</sub> of ~10 nM (folate-PHQ). We also demonstrate that a cleavable spacer linking folate to PHQ is significantly inferior to a noncleavable spacer, in contrast to most other folate-targeted therapeutic agents. Unfortunately, no evidence for folate-PHQ mediated tumor regression in murine tumor models is obtained, suggesting that unanticipated impediments to generation of cytotoxic quantities of ROS in vivo are encountered. Possible mechanisms and potential solutions to these unanticipated results are offered.
文摘To assess targeting of an epothilone folate conjugate(BMS-753493) to the folate receptor(FR)-overexpressed tumor in mice bearing both FRt and FR– tumors,a series of experiments were conducted by quantitative whole-body autoradiography(QWBA) and LC–MS/MS following i.v.administration of BMS-753493 or its active moiety,BMS-748285 in mice bearing FRt(98M109) and FR–(M109) tumors.QWBA showed [3H]BMS-753493–derived radioactivity was extensively distributed to various tissues.The FR over-expressing 98M109 tumors showed consistently higher level of radioactivity than FR-negative tumors(i.e.,M109 tumors) up to 48 h post dose of [3H]BMS-753493,despite the magnitude of difference between the tumors is relatively small(generally 3 5-fold).The radioactivity level in 98M109 tumors was 2 12-fold of normal tissues except intestine/content at 48 h post dose.No selective radioactivity uptake into 98M109 tumors over M109 or normal tissues was observed after i.v.administration of the active epothilone,[3H]BMS-748285.LC–MS/MS measurements demonstrated that the concentrations of BMS-748285,presumably from hydrolysis of the folate conjugate,in 98M109 tumors were greater than those in M109 tumors after i.v.administration of BMS-753493(2–3-fold) whereas no differential uptake in the tumors following BMS-748285 administration.Those data were consistent with radioactivity determinations.Those results demonstrated that the folate conjugation in BMS-753493 enabled moderately preferential distribution of the active epothilone to FR overexpressing 98M109 tumors,thereby supporting targeted delivery of cytotoxics through the folate receptor.
基金supported by the National Natural Science Foundation of China (81072084)
文摘Invasive nonfunctional pituitary adenomas （NFPAs） are difficult to completely resect and often develop tumor recurrence after initial surgery. Currently, no medications are clinically effective in the control of NFPA. Although radiation therapy and radiosurgery are useful to prevent tumor regrowth, they are frequently withheld because of severe complications. Boron neutron capture therapy （BNCT） is a binary radiotherapy that selectively and maximally damages tumor cells without harming the surrounding normal tissue. Folate receptor （FR）-targeted boron-10 containing carbon nanoparticles is a novel boron delivery agent that can be selectively taken up by FR-expressing cells via FR-mediated endocytosis. In this study, FR-targeted boron-10 containing carbon nanoparticles were selectively taken up by NFPAs cells expressing FR but not other types of non-FR expressing pituitary adenomas. After incubation with boron-10 containing carbon nanoparticles and following irradiation with thermal neutrons, the cell viability of NFPAs was significantly decreased, while apoptotic cells were simultaneously increased. However, cells administered the same dose of FR-targeted boron-10 containing carbon nanoparticles without neutron irradiation or received the same neutron irradiation alone did not show significant decrease in cell viability or increase in apoptotic cells. The expression of Bcl-2 was down-regulated and the expression of Bax was up-regulated in NFPAs after treatment with FR-mediated BNCT. In conclusion, FR-targeted boron-10 containing carbon nanoparticles may be an ideal delivery system of boron to NFPAs ceils for BNCT. Furthermore, our study also provides a novel insight into therapeutic strategies for invasive NFPA refractory to conventional therapy, while exploring these new applications of BNCT for tumors, especially benign tumors.
基金supported by the National Postdoctoral Program for Innovative Talents(No.BX201700142)Postdoctoral Science Foundation of China(No.2018M630732)+3 种基金the National Natural Science Foundation of China(Nos.81901805,21906135,81471707,21705037,and 91539126)Hunan Provincial Natural Science Foundation of China(No.2018JJ3092)Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(CIFMS 2016-I2M-1-009)Drug Innovation Major Project(2018ZX09711001-003-011).
文摘Vulnerable atherosclerotic plaques are responsible for most cardiovascular diseases(CVDs).Folate receptor(FR)positive activated macrophages were thought to be a prominent component in the development of vulnerable plaque.The objective of this study is to develop folate conjugated two-dimensional(2D)Pd@Au nanomaterials(Pd@Au-PEG-FA)for targeted multimodal imaging of the FRs in advanced atherosclerotic plaques.Pharmacokinetic and imaging studies(single photon emission computed tomography(SPECT),computed tomography(CT)and photoacoustic(PA)imaging)were performed to confirm the prolonged blood half-life and enrichment of radioactivity in atherosclerotic plaques.Strong signals were detected in vivo with SPECT,CT and PA imaging in heavy atherosclerotic plaques,which were significantly higher than those of the normal aortas after injection of Pd@Au-PEG-FA.Blocking studies with preinjection of excess FA could effectively reduce the targeting ability of Pd@Au-PEG-FA in atherosclerotic plaques,further demonstrating the specific binding of Pd@Au-PEG-FA for plaque lesions.Histopathological characterization revealed that the signal of probe was in accordance with the high-risk plaques.In summary,the Pd@Au-PEG-FA has favorable pharmacokinetic properties and provides a valuable approach for detecting high-risk plaques in the presence of FRs in atherosclerotic plaques.
