Localized prostate cancer is curable via annihilation of the entire cancer neighborhood by surgery or local radiation.Unfortunately,once metastatic,no available therapy is curative.The vast majority will die despite a...Localized prostate cancer is curable via annihilation of the entire cancer neighborhood by surgery or local radiation.Unfortunately,once metastatic,no available therapy is curative.The vast majority will die despite aggressive systemic combinational androgenablation therapies.Thus,there is an urgent need for effective systemic therapeutics that sterilize the entire microenvironment in metastatic castration-resistant prostate cancer(mCRPC).To accomplish this goal,advantage can be taken of the unique biology of mCRPC cells.Like their normal cell of origin,mCRPCs retain expression of the prostate-specific differentiation protein,prostate-specific antigen(PSA),which they abundantly secrete into their extracellular fluid(ECF).This unique,and essentially universal,secretion of enzymatically active PSA into the ECF by mCRPCs creates an exploitable therapeutic index for activation of systemically delivered highly lipophilic toxins as“molecular grenades”covalently linked to cysteine-34 of human serum albumin(HSA)via a stable maleimide containing PSA cleavable peptide such that PSA-dependent hydrolysis(i.e.,“detonation”)releases the grenades restrictively within the ECF of mCRPC.This approach decreases dose-limiting host toxicity while enhancing plasma half-life from minutes to days(i.e.,pharmacokinetic effect)and increasing the tissue concentration of the maleimide coupled albumin delivery(MAD)in the ECF at sites of cancer due to the enhanced permeability of albumin at these sites(i.e.,enhanced permeability and retention effect).This allows the MAD-PSA detonated grenades to circulate throughout the body in a non-toxic form.Only within sites of mCRPC is there a sufficiently high level of enzymatically active PSA to efficiently“pull the pin”on the grenades releasing their lipophilic cellpenetrant toxins from HSA.Thus,if a sufficient level of“detonation”occurs,this will kill mCRPC cells,and sterilize the entire PSA-rich metastatic sites via a bystander effect.In this review,two examples of such MAD-PSA detonated molecular grenades are presenteddone based upon thapsigagin and the other on niclosamide.展开更多
Ovarian cancer(OC)is one of the most lethal malignancies of the female reproduc-tive system.OC patients are usually diagnosed at advanced stages due to the lack of early diag-nosis.The standard treatment for OC includ...Ovarian cancer(OC)is one of the most lethal malignancies of the female reproduc-tive system.OC patients are usually diagnosed at advanced stages due to the lack of early diag-nosis.The standard treatment for OC includes a combination of debulking surgery and platinum-taxane chemotherapy,while several targeted therapies have recently been approved for maintenance treatment.The vast majority of OC patients relapse with chemoresistant tu-mors after an initial response.Thus,there is an unmet clinical need to develop new therapeu-tic agents to overcome the chemoresistance of OC.The anti-parasite agent niclosamide(NA)has been repurposed as an anti-cancer agent and exerts potent anti-cancer activities in human cancers including OC.Here,we investigated whether NA could be repurposed as a therapeutic agent to overcome cisplatin-resistant(CR)in human OC cells.To this end,we first established two CR lines SKOV3CR and OVCAR8CR that exhibit the essential biological characteristics of cisplatin resistance in human cancer.We showed that NA inhibited cell proliferation,sup-pressed cell migration,and induced cell apoptosis in both CR lines at a low micromole range.Mechanistically,NA inhibited multiple cancer-related pathways including AP1,ELK/SRF,HIF1,and TCF/LEF,in SKOV3CR and OVCAR8CR cells.NA was further shown to effectively inhibit xenograft tumor growth of SKOV3CR cells.Collectively,our findings strongly suggest that NA may be repurposed as an efficacious agent to combat cisplatin resistance in chemoresistant hu-man OC,and further clinical trials are highly warranted.展开更多
Porcine epidemic diarrhea virus(PEDV),an enteropathogenic coronavirus,has catastrophic impacts on the global pig industry.However,there remain no effective drugs against PEDV infection.In this study,we utilized a reco...Porcine epidemic diarrhea virus(PEDV),an enteropathogenic coronavirus,has catastrophic impacts on the global pig industry.However,there remain no effective drugs against PEDV infection.In this study,we utilized a recombinant PEDV expressing renilla luciferase(PEDV-Rluc)to screen potential anti-PEDV agents from an FDAapproved drug library in Vero cells.Four compounds were identified that significantly decreased luciferase activity of PEDV-Rluc.Among them,niclosamide was further characterized because it exhibited the most potent antiviral activity with the highest selectivity index.It can efficiently inhibit viral RNA synthesis,protein expression and viral progeny production of classical and variant PEDV strains in a dose-dependent manner.Time of addition assay showed that niclosamide exhibited potent anti-PEDV activity when added simultaneously with or after virus infection.Furthermore,niclosamide significantly inhibited the entry stage of PEDV infection by affecting viral internalization rather than viral attachment to cells.In addition,a combination with other small molecule inhibitors of endosomal acidification enhanced the anti-PEDV effect of niclosamide in vitro.Taken together,these findings suggested that niclosamide is a novel antiviral agent that might provide a basis for the development of novel drug therapies against PEDV and other related pathogenic coronavirus infections.展开更多
To study the toxicity of extracts of Ginkgo biloba sarcotesta to Oncomelania hupensis,snails were exposed to 40% and 80% of 24 h LC 50 of the extract of Ginkgo bilba for 24 h,choline esterase(ChE),alanine aminotransfe...To study the toxicity of extracts of Ginkgo biloba sarcotesta to Oncomelania hupensis,snails were exposed to 40% and 80% of 24 h LC 50 of the extract of Ginkgo bilba for 24 h,choline esterase(ChE),alanine aminotransferase(ALT),alkaline phosphatase(ALP),lactate dehydrogenase(LDH),succino dehydrogenase(SDH),malic dehydrogenase(MDH)activities in cephalopodium and liver were determined by enzyme kinetic assay.Arecoline and niclosamide were used as reference molluscicides.The results showed that sarcotesta of Ginkgo biloba could inhibit ChE,ALT,ALP and MDH activities both in cephalopodium and liver;arecoline could inhibit ChE,ALP,SDH and MDH activities in cephalopodium and ChE,ALT,ALP,SDH and MDH activities in liver.Niclosamide had inhibitory effects upon ChE,ALT,ALP,SDH and MDH activities in cephalopodium,and ChE,ALT,ALP and SDH activities in liver.All three molluscicides did not inhibite LDH activity in cephalopodium and liver.These results indicate that lethal effects of extracts of sarcotesta of Ginkgo biloba are mediated via inhibition of MDH activitiy,and interference with the NADH respiratory chains.Inhibition of vital enzymic mechanisms causes snails to death.展开更多
Schistosomiasis is a snail-transmitted infectious disease affecting over 200 million people worldwide.Snail control has been recognized as an effective approach to interrupt the transmission of schistosomiasis,since t...Schistosomiasis is a snail-transmitted infectious disease affecting over 200 million people worldwide.Snail control has been recognized as an effective approach to interrupt the transmission of schistosomiasis,since the geographic distribution of this neglected tropical disease is determined by the presence of the intermediate host snails.In a recent Scoping Review published in Infectious Diseases of Poverty,Coelho and Caldeira performed a critical review of using molluscicides in the national schistosomiasis control programs in Brazil.They also described some chemical and plant-derived molluscicides used in China.In addition to the molluscicides described by Coelho and Caldeira,a large number of chemicals,plant extracts and microorganisms have been screened and tested for molluscicidal actions against Oncomelania hupensis,the intermediate host of Schistosoma japonicum in China.Here,we presented the currently commercial molluscicides available in China,including 26%suspension concentrate of metaldehyde and niclosamide(MNSC),25%suspension concentrate of niclosamide ethanolamine salt(SCNE),50%niclosamide ethanolamine salt wettable powder(WPN),4%niclosamide ethanolamine salt dustable powder(NESP),5%niclosamide ethanolamine salt granule(NESG)and the plant-derived molluscicide“Luowei”.These molluscicides have been proved to be active against O.hupensis in both laboratory and endemic fields,playing an important role in the national schistosomiasis control program of China.Currently,China is transferring its successful experiences on schistosomiasis control to African countries.The introduction of Chinese commercial molluscicides to Africa,with adaptation to local conditions,may facilitate the progress towards the elimination of schisosomiasis in Africa.展开更多
基金We would like to acknowledge the Prostate Cancer Foundation,Department of Defense Prostate Cancer Research Program(W81XWH-16-1-0410)NIH Prostate SPORE(P50 CA058236)Patrick C.Walsh Prostate Cancer Research Fund,and the Hopkins-Allegheny Health Network Cancer Research Fund。
文摘Localized prostate cancer is curable via annihilation of the entire cancer neighborhood by surgery or local radiation.Unfortunately,once metastatic,no available therapy is curative.The vast majority will die despite aggressive systemic combinational androgenablation therapies.Thus,there is an urgent need for effective systemic therapeutics that sterilize the entire microenvironment in metastatic castration-resistant prostate cancer(mCRPC).To accomplish this goal,advantage can be taken of the unique biology of mCRPC cells.Like their normal cell of origin,mCRPCs retain expression of the prostate-specific differentiation protein,prostate-specific antigen(PSA),which they abundantly secrete into their extracellular fluid(ECF).This unique,and essentially universal,secretion of enzymatically active PSA into the ECF by mCRPCs creates an exploitable therapeutic index for activation of systemically delivered highly lipophilic toxins as“molecular grenades”covalently linked to cysteine-34 of human serum albumin(HSA)via a stable maleimide containing PSA cleavable peptide such that PSA-dependent hydrolysis(i.e.,“detonation”)releases the grenades restrictively within the ECF of mCRPC.This approach decreases dose-limiting host toxicity while enhancing plasma half-life from minutes to days(i.e.,pharmacokinetic effect)and increasing the tissue concentration of the maleimide coupled albumin delivery(MAD)in the ECF at sites of cancer due to the enhanced permeability of albumin at these sites(i.e.,enhanced permeability and retention effect).This allows the MAD-PSA detonated grenades to circulate throughout the body in a non-toxic form.Only within sites of mCRPC is there a sufficiently high level of enzymatically active PSA to efficiently“pull the pin”on the grenades releasing their lipophilic cellpenetrant toxins from HSA.Thus,if a sufficient level of“detonation”occurs,this will kill mCRPC cells,and sterilize the entire PSA-rich metastatic sites via a bystander effect.In this review,two examples of such MAD-PSA detonated molecular grenades are presenteddone based upon thapsigagin and the other on niclosamide.
基金supported in part by research grants from the National Institutes of Health(No.CA226303 to TCH,No.DE030480 to RRR)supported by the Medical Scientist Training Program of the National Institutes of Health(USA)(No.T32 GM007281)+2 种基金supported in part by The University of Chicago Cancer Center Support Grant(No.P30CA014599)the National Center for Advancing Translational Sciences of the National Institutes of Health(USA)(No.UL1 TR000430)supported by the Mabel Green Myers Research Endowment Fund and The University of Chicago Orthopaedics Alumni Fund.
文摘Ovarian cancer(OC)is one of the most lethal malignancies of the female reproduc-tive system.OC patients are usually diagnosed at advanced stages due to the lack of early diag-nosis.The standard treatment for OC includes a combination of debulking surgery and platinum-taxane chemotherapy,while several targeted therapies have recently been approved for maintenance treatment.The vast majority of OC patients relapse with chemoresistant tu-mors after an initial response.Thus,there is an unmet clinical need to develop new therapeu-tic agents to overcome the chemoresistance of OC.The anti-parasite agent niclosamide(NA)has been repurposed as an anti-cancer agent and exerts potent anti-cancer activities in human cancers including OC.Here,we investigated whether NA could be repurposed as a therapeutic agent to overcome cisplatin-resistant(CR)in human OC cells.To this end,we first established two CR lines SKOV3CR and OVCAR8CR that exhibit the essential biological characteristics of cisplatin resistance in human cancer.We showed that NA inhibited cell proliferation,sup-pressed cell migration,and induced cell apoptosis in both CR lines at a low micromole range.Mechanistically,NA inhibited multiple cancer-related pathways including AP1,ELK/SRF,HIF1,and TCF/LEF,in SKOV3CR and OVCAR8CR cells.NA was further shown to effectively inhibit xenograft tumor growth of SKOV3CR cells.Collectively,our findings strongly suggest that NA may be repurposed as an efficacious agent to combat cisplatin resistance in chemoresistant hu-man OC,and further clinical trials are highly warranted.
基金supported by the National Natural Science Foundation of China(Grant No.31602033 and 32172839)the China Scholarship Council under grant 201908410129.
文摘Porcine epidemic diarrhea virus(PEDV),an enteropathogenic coronavirus,has catastrophic impacts on the global pig industry.However,there remain no effective drugs against PEDV infection.In this study,we utilized a recombinant PEDV expressing renilla luciferase(PEDV-Rluc)to screen potential anti-PEDV agents from an FDAapproved drug library in Vero cells.Four compounds were identified that significantly decreased luciferase activity of PEDV-Rluc.Among them,niclosamide was further characterized because it exhibited the most potent antiviral activity with the highest selectivity index.It can efficiently inhibit viral RNA synthesis,protein expression and viral progeny production of classical and variant PEDV strains in a dose-dependent manner.Time of addition assay showed that niclosamide exhibited potent anti-PEDV activity when added simultaneously with or after virus infection.Furthermore,niclosamide significantly inhibited the entry stage of PEDV infection by affecting viral internalization rather than viral attachment to cells.In addition,a combination with other small molecule inhibitors of endosomal acidification enhanced the anti-PEDV effect of niclosamide in vitro.Taken together,these findings suggested that niclosamide is a novel antiviral agent that might provide a basis for the development of novel drug therapies against PEDV and other related pathogenic coronavirus infections.
文摘To study the toxicity of extracts of Ginkgo biloba sarcotesta to Oncomelania hupensis,snails were exposed to 40% and 80% of 24 h LC 50 of the extract of Ginkgo bilba for 24 h,choline esterase(ChE),alanine aminotransferase(ALT),alkaline phosphatase(ALP),lactate dehydrogenase(LDH),succino dehydrogenase(SDH),malic dehydrogenase(MDH)activities in cephalopodium and liver were determined by enzyme kinetic assay.Arecoline and niclosamide were used as reference molluscicides.The results showed that sarcotesta of Ginkgo biloba could inhibit ChE,ALT,ALP and MDH activities both in cephalopodium and liver;arecoline could inhibit ChE,ALP,SDH and MDH activities in cephalopodium and ChE,ALT,ALP,SDH and MDH activities in liver.Niclosamide had inhibitory effects upon ChE,ALT,ALP,SDH and MDH activities in cephalopodium,and ChE,ALT,ALP and SDH activities in liver.All three molluscicides did not inhibite LDH activity in cephalopodium and liver.These results indicate that lethal effects of extracts of sarcotesta of Ginkgo biloba are mediated via inhibition of MDH activitiy,and interference with the NADH respiratory chains.Inhibition of vital enzymic mechanisms causes snails to death.
基金This study was supported by the grant from Jiangsu Department of Health(grantno.Q201404).
文摘Schistosomiasis is a snail-transmitted infectious disease affecting over 200 million people worldwide.Snail control has been recognized as an effective approach to interrupt the transmission of schistosomiasis,since the geographic distribution of this neglected tropical disease is determined by the presence of the intermediate host snails.In a recent Scoping Review published in Infectious Diseases of Poverty,Coelho and Caldeira performed a critical review of using molluscicides in the national schistosomiasis control programs in Brazil.They also described some chemical and plant-derived molluscicides used in China.In addition to the molluscicides described by Coelho and Caldeira,a large number of chemicals,plant extracts and microorganisms have been screened and tested for molluscicidal actions against Oncomelania hupensis,the intermediate host of Schistosoma japonicum in China.Here,we presented the currently commercial molluscicides available in China,including 26%suspension concentrate of metaldehyde and niclosamide(MNSC),25%suspension concentrate of niclosamide ethanolamine salt(SCNE),50%niclosamide ethanolamine salt wettable powder(WPN),4%niclosamide ethanolamine salt dustable powder(NESP),5%niclosamide ethanolamine salt granule(NESG)and the plant-derived molluscicide“Luowei”.These molluscicides have been proved to be active against O.hupensis in both laboratory and endemic fields,playing an important role in the national schistosomiasis control program of China.Currently,China is transferring its successful experiences on schistosomiasis control to African countries.The introduction of Chinese commercial molluscicides to Africa,with adaptation to local conditions,may facilitate the progress towards the elimination of schisosomiasis in Africa.