Hypoxia-inducible factor-1 (HIF-1) has been recognized as an important cancer drug target. Many recent studies have provided convincing evidences of strong correlation between elevated levels of HIF-1 and tumor metast...Hypoxia-inducible factor-1 (HIF-1) has been recognized as an important cancer drug target. Many recent studies have provided convincing evidences of strong correlation between elevated levels of HIF-1 and tumor metastasis, angiogenesis, poor patient prognosis as well as tumor resistance therapy. It was found that hypoxia (low O<sub>2</sub> levels) is a common character in many types of solid tumors. As an adaptive response to hypoxic stress, hypoxic tumor cells activate several survival pathways to carry out their essential biological processes in different ways compared with normal cells. Recent advances in cancer biology at the cellular and molecular levels highlighted the HIF-1α pathway as a crucial survival pathway for which novel strategies of cancer therapy could be developed. However, targeting the HIF-1α pathway has been a challenging but promising progresses have been made in the past twenty years. This review summarizes the role and regulation of the HIF-1α in cancer, and recent therapeutic approaches targeting this important pathway.展开更多
Two-dimensional graphene offers interesting electronic,thermal,and mechanical properties that are currently being explored for advanced electronics,membranes,and composites.Here we synthesize and explore the biologica...Two-dimensional graphene offers interesting electronic,thermal,and mechanical properties that are currently being explored for advanced electronics,membranes,and composites.Here we synthesize and explore the biological applications of nano-graphene oxide(NGO),i.e.,single-layer graphene oxide sheets down to a few nanometers in lateral width.We develop functionalization chemistry in order to impart solubility and compatibility of NGO in biological environments.We obtain size separated pegylated NGO sheets that are soluble in buffers and serum without agglomeration.The NGO sheets are found to be photoluminescent in the visible and infrared regions.The intrinsic photoluminescence(PL)of NGO is used for live cell imaging in the near-infrared(NIR)with little background.We found that simple physisorption viaπ-stacking can be used for loading doxorubicin,a widely used cancer drug onto NGO functionalized with antibody for selective killing of cancer cells in vitro.Owing to its small size,intrinsic optical properties,large specifi c surface area,low cost,and useful non-covalent interactions with aromatic drug molecules,NGO is a promising new material for biological and medical applications.展开更多
Exosomes are small intracellular membrane-based vesicles with different compositions that are involved in several biological and pathological processes. The exploitation of exosomes as drug delivery vehicles offers im...Exosomes are small intracellular membrane-based vesicles with different compositions that are involved in several biological and pathological processes. The exploitation of exosomes as drug delivery vehicles offers important advantages compared to other nanoparticulate drug delivery systems such as liposomes and polymeric nanoparticles; exosomes are non-immunogenic in nature due to similar composition as body's own cells. In this article, the origin and structure of exosomes as well as their biological functions are outlined. We will then focus on specific applications of exosomes as drug delivery systems in pharmaceutical drug development. An overview of the advantages and challenges faced when using exosomes as a pharmaceutical drug delivery vehicles will also be discussed.展开更多
Background Appropriate antimicrobial therapy of community-acquired pneumonia （CAP） is mainly based on the distribution of etiology and antimicrobial resistance of major pathogens. We performed a prospective observat...Background Appropriate antimicrobial therapy of community-acquired pneumonia （CAP） is mainly based on the distribution of etiology and antimicrobial resistance of major pathogens. We performed a prospective observational study of adult with CAP in 36 hospitals in China. Methods Etiological pathogens were isolated in each of the centers, and all of the isolated pathogens were sent to Zhongshan Hospital for antimicrobial susceptibility tests using agar dilution. Results A total of 593 patients were enrolled in this study, and 242 strains of bacteria were isolated from 225 patients. Streptococcus pneumoniae （79/242, 32.6%） was the most frequently isolated pathogen, followed by Haemophilus influenzae （55/242, 22.7%） and Klebsiella pneumoniae （25/242, 10.3%）. Totally 527 patients underwent serological tests for atypical pathogens; Mycoplasma pneumoniae and Chlamydia pneumoniae infections were identified in 205 （38.9%） and 60 （11.4%） patients respectively. Legionella pneumophila infections were identified in 4.0% （13/324） of patients. The non-susceptibility rate of isolated Streptococcus pneumoniae to erythromycin and penicillin was 63.2% and 19.1% respectively. Six patients died from the disease, the 30-day mortality rate was 1.1% （6/533）. Conclusions The top three bacteria responsible for CAP in Chinese adults were Streptococcus pneumonia, Haemophilus influenza and Klebsiella pneumonia. There was also a high prevalence of atypical pathogens and mixed pathogens. The resistance rates of the major isolated pathogens were relatively low except for the high prevalence of macrolide resistance in Streptococcus pneumoniae.展开更多
Multidrug resistance(MDR) occurs frequently after long-term chemotherapy, resulting in refractory cancer and tumor recurrence.Therefore, combatting MDR is an important issue. Autophagy, a self-degradative system, univ...Multidrug resistance(MDR) occurs frequently after long-term chemotherapy, resulting in refractory cancer and tumor recurrence.Therefore, combatting MDR is an important issue. Autophagy, a self-degradative system, universally arises during the treatment of sensitive and MDR cancer. Autophagy can be a double-edged sword for MDR tumors: it participates in the development of MDR and protects cancer cells from chemotherapeutics but can also kill MDR cancer cells in which apoptosis pathways are inactive. Autophagy induced by anticancer drugs could also activate apoptosis signaling pathways in MDR cells, facilitating MDR reversal. Therefore, research on the regulation of autophagy to combat MDR is expanding and is becoming increasingly important. We summarize advanced studies of autophagy in MDR tumors, including the variable role of autophagy in MDR cancer cells.展开更多
Wnt signaling transduces evolutionarily conserved pathways which play important roles in initiating and regulating a diverse range of cellular activities,including cell proliferation,calcium homeostasis,and cell polar...Wnt signaling transduces evolutionarily conserved pathways which play important roles in initiating and regulating a diverse range of cellular activities,including cell proliferation,calcium homeostasis,and cell polarity.The role of Wnt signaling in controlling cell proliferation and stem cell self-renewal is primarily carried out through the canonical pathway,which is the best-characterized the multiple Wnt signaling branches.The past 10 years has seen a rapid expansion in our understanding of the complexity of this pathway,as many new components of Wnt signaling have been identified and linked to signaling regulation,stem cell functions,and adult tissue homeostasis.Additionally,a substantial body of evidence links Wnt signaling to tumorigenesis of cancer types and implicates it in the development of cancer drug resistance.Thus,a better understanding of the mechanisms by which dysregulation of Wnt signaling precedes the development and progression of human cancer may hasten the development of pathway inhibitors to augment current therapy.This review summarizes and synthesizes our current knowledge of the canonical Wnt pathway in development and disease.We begin with an overview of the components of the canonical Wnt signaling pathway and delve into the role this pathway has been shown to play in stemness,tumorigenesis,and cancer drug resistance.Ultimately,we hope to present an organized collection of evidence implicating Wnt signaling in tumorigenesis and chemoresistance to facilitate the pursuit of Wnt pathway modulators that may improve outcomes of cancers in which Wnt signaling contributes to aggressive disease and/or treatment resistance.展开更多
SARS-CoV-2 has caused tens of thousands of infections and more than one thousand deaths.There are currently no registered therapies for treating coronavirus infections.Because of time consuming process of new drug dev...SARS-CoV-2 has caused tens of thousands of infections and more than one thousand deaths.There are currently no registered therapies for treating coronavirus infections.Because of time consuming process of new drug development,drug repositioning may be the only solution to the epidemic of sudden infectious diseases.We systematically analyzed all the proteins encoded by SARS-CoV-2 genes,compared them with proteins from other coronavirnses,predicted their structures,and built 19 structures that could be done by homology modeling.By performing target-based virtual ligand screening,a total of21 targets(including two human targets)were screened against compound libraries including ZINC drug database and our own database of natural products.Structure and screening results of important targets such as 3-chymotrypsin-like protease(3 CLpro),Spike,RNA-dependent RNA polymerase(RdRp),and papain like protease(PLpro)were discussed in detail.In addition,a database of 78 commonly used antiviral drugs including those currently on the market and undergoing clinical trials for SARS-CoV-2 was constructed.Possible targets of these compounds and potential drugs acting on a certain target were predicted.This study will provide new lead compounds and targets for further in vitro and in vivo studies of SARS-CoV-2,new insights for those drugs currently ongoing clinical studies,and also possible new strategies for drug repositioning to treat SARS-CoV-2 infections.展开更多
Colorectal cancer(CRC)is a very heterogeneous disease that is caused by the interaction of genetic and environmental factors.CRC develops through a gradual accumulation of genetic and epigenetic changes,leading to the...Colorectal cancer(CRC)is a very heterogeneous disease that is caused by the interaction of genetic and environmental factors.CRC develops through a gradual accumulation of genetic and epigenetic changes,leading to the transformation of normal colonic mucosa into invasive cancer.CRC is one of the most prevalent and incident cancers worldwide,as well as one of the most deadly.Approximately 1235108 people are diagnosed annually with CRC,and 609051 die from CRC annually.The World Health Organization estimates an increase of77%in the number of newly diagnosed cases of CRCand an increase of 80%in deaths from CRC by 2030.The incidence of CRC can benefit from different strategies depending on its stage:health promotion through health education campaigns(when the disease is not yet present),the implementation of screening programs(for detection of the disease in its early stages),and the development of nearly personalized treatments according to both patient characteristics(age,sex)and the cancer itself(gene expression).Although there are different strategies for screening and although the number of such strategies is increasing due to the potential of emerging technologies in molecular marker application,not all strategies meet the criteria required for screening tests in population programs;the three most accepted tests are the fecal occult blood test(FOBT),colonoscopy and sigmoidoscopy.FOBT is the most used method for CRC screening worldwide and is also the primary choice in most population-based screening programs in Europe.Due to its non-invasive nature and low cost,it is one of the most accepted techniques by population.CRC is a very heterogeneous disease,and with a few exceptions(APC,p53,KRAS),most of the genes involved in CRC are observed in a small percentage of cases.The design of genetic and epigenetic marker panels that are able to provide maximum coverage in the diagnosis of colorectal neoplasia seems a reasonable strategy.In recent years,the use of DNA,RNA and protein markers in different biological samples 展开更多
Epithelial-to-mesenchymal transition(EMT)is implicated in a wide array of malignant behaviors of cancers,including proliferation,invasion,and metastasis.Most notably,previou studies have indicated that both cancer ste...Epithelial-to-mesenchymal transition(EMT)is implicated in a wide array of malignant behaviors of cancers,including proliferation,invasion,and metastasis.Most notably,previou studies have indicated that both cancer stem-like properties and drug resistance were associated with EMT.Furthermore,microRNAs(miRNAs)play a pivotal role in the regulation of EMT phenotype,as a result,some miRNAs impact cancer stemness and drug resistance.Therefore,understanding the relationship between EMT-associated miRNAs and cancer stemness/drug resistance is beneficial to both basic research and clinical treatment.In this review,we preliminarily looked into the various roles that the EMT-associated miRNAs play in the stem-like nature of malignant cells.Then,we reviewed the interaction between EMT-associated miRNAs and the drugresistant complex signaling pathways of multiple cancers including lung cancer,gastric cancer,gynecologic cancer,breast cancer,liver cancer,colorectal cancer,pancreatic cancer,esophageal cancer,and nasopharyngeal cancer.We finally discussed the relationship between EMT,cancer stemness,and drug resistance,as well as looked forward to the potential applications of miRNA therapy for malignant tumors.展开更多
基金partially supported by the NIH grant 1R01CA148706funds from the University of Tennessee Health Science Center, College of Pharmacy
文摘Hypoxia-inducible factor-1 (HIF-1) has been recognized as an important cancer drug target. Many recent studies have provided convincing evidences of strong correlation between elevated levels of HIF-1 and tumor metastasis, angiogenesis, poor patient prognosis as well as tumor resistance therapy. It was found that hypoxia (low O<sub>2</sub> levels) is a common character in many types of solid tumors. As an adaptive response to hypoxic stress, hypoxic tumor cells activate several survival pathways to carry out their essential biological processes in different ways compared with normal cells. Recent advances in cancer biology at the cellular and molecular levels highlighted the HIF-1α pathway as a crucial survival pathway for which novel strategies of cancer therapy could be developed. However, targeting the HIF-1α pathway has been a challenging but promising progresses have been made in the past twenty years. This review summarizes the role and regulation of the HIF-1α in cancer, and recent therapeutic approaches targeting this important pathway.
基金by NIH-NCI funded CCNE TR at Stanford University.We are grateful to Drs.Alice Fan and Dean Felsher for providing the antibodies used in this work.
文摘Two-dimensional graphene offers interesting electronic,thermal,and mechanical properties that are currently being explored for advanced electronics,membranes,and composites.Here we synthesize and explore the biological applications of nano-graphene oxide(NGO),i.e.,single-layer graphene oxide sheets down to a few nanometers in lateral width.We develop functionalization chemistry in order to impart solubility and compatibility of NGO in biological environments.We obtain size separated pegylated NGO sheets that are soluble in buffers and serum without agglomeration.The NGO sheets are found to be photoluminescent in the visible and infrared regions.The intrinsic photoluminescence(PL)of NGO is used for live cell imaging in the near-infrared(NIR)with little background.We found that simple physisorption viaπ-stacking can be used for loading doxorubicin,a widely used cancer drug onto NGO functionalized with antibody for selective killing of cancer cells in vitro.Owing to its small size,intrinsic optical properties,large specifi c surface area,low cost,and useful non-covalent interactions with aromatic drug molecules,NGO is a promising new material for biological and medical applications.
文摘Exosomes are small intracellular membrane-based vesicles with different compositions that are involved in several biological and pathological processes. The exploitation of exosomes as drug delivery vehicles offers important advantages compared to other nanoparticulate drug delivery systems such as liposomes and polymeric nanoparticles; exosomes are non-immunogenic in nature due to similar composition as body's own cells. In this article, the origin and structure of exosomes as well as their biological functions are outlined. We will then focus on specific applications of exosomes as drug delivery systems in pharmaceutical drug development. An overview of the advantages and challenges faced when using exosomes as a pharmaceutical drug delivery vehicles will also be discussed.
文摘Background Appropriate antimicrobial therapy of community-acquired pneumonia （CAP） is mainly based on the distribution of etiology and antimicrobial resistance of major pathogens. We performed a prospective observational study of adult with CAP in 36 hospitals in China. Methods Etiological pathogens were isolated in each of the centers, and all of the isolated pathogens were sent to Zhongshan Hospital for antimicrobial susceptibility tests using agar dilution. Results A total of 593 patients were enrolled in this study, and 242 strains of bacteria were isolated from 225 patients. Streptococcus pneumoniae （79/242, 32.6%） was the most frequently isolated pathogen, followed by Haemophilus influenzae （55/242, 22.7%） and Klebsiella pneumoniae （25/242, 10.3%）. Totally 527 patients underwent serological tests for atypical pathogens; Mycoplasma pneumoniae and Chlamydia pneumoniae infections were identified in 205 （38.9%） and 60 （11.4%） patients respectively. Legionella pneumophila infections were identified in 4.0% （13/324） of patients. The non-susceptibility rate of isolated Streptococcus pneumoniae to erythromycin and penicillin was 63.2% and 19.1% respectively. Six patients died from the disease, the 30-day mortality rate was 1.1% （6/533）. Conclusions The top three bacteria responsible for CAP in Chinese adults were Streptococcus pneumonia, Haemophilus influenza and Klebsiella pneumonia. There was also a high prevalence of atypical pathogens and mixed pathogens. The resistance rates of the major isolated pathogens were relatively low except for the high prevalence of macrolide resistance in Streptococcus pneumoniae.
基金supported by the Science and Technology Program of China (2012ZX09103101-053)the Natural Science Foundation of Guangdong Province (52013050014183 and 2013CXZDA006)+1 种基金the Program for New Century Excellent Talents in University (D.M.Zhang)the project was supported by Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme (D. M. Zhang)
文摘Multidrug resistance(MDR) occurs frequently after long-term chemotherapy, resulting in refractory cancer and tumor recurrence.Therefore, combatting MDR is an important issue. Autophagy, a self-degradative system, universally arises during the treatment of sensitive and MDR cancer. Autophagy can be a double-edged sword for MDR tumors: it participates in the development of MDR and protects cancer cells from chemotherapeutics but can also kill MDR cancer cells in which apoptosis pathways are inactive. Autophagy induced by anticancer drugs could also activate apoptosis signaling pathways in MDR cells, facilitating MDR reversal. Therefore, research on the regulation of autophagy to combat MDR is expanding and is becoming increasingly important. We summarize advanced studies of autophagy in MDR tumors, including the variable role of autophagy in MDR cancer cells.
基金The authors’research efforts were supported in part by research grants from the NIH(AT004418 to TCH)the 973 Program of Ministry of Science and Technology(MOST)of China(#2011CB707900 to TCH)+1 种基金the Scoliosis Research Society(to MJL),MKM was a recipient of Howard Hughes Medical Institute Medical Research FellowshipCS was a recipient of the Pritzker Summer Research Fellowship funded through a NIH T-35 training grant(NIDDK).
文摘Wnt signaling transduces evolutionarily conserved pathways which play important roles in initiating and regulating a diverse range of cellular activities,including cell proliferation,calcium homeostasis,and cell polarity.The role of Wnt signaling in controlling cell proliferation and stem cell self-renewal is primarily carried out through the canonical pathway,which is the best-characterized the multiple Wnt signaling branches.The past 10 years has seen a rapid expansion in our understanding of the complexity of this pathway,as many new components of Wnt signaling have been identified and linked to signaling regulation,stem cell functions,and adult tissue homeostasis.Additionally,a substantial body of evidence links Wnt signaling to tumorigenesis of cancer types and implicates it in the development of cancer drug resistance.Thus,a better understanding of the mechanisms by which dysregulation of Wnt signaling precedes the development and progression of human cancer may hasten the development of pathway inhibitors to augment current therapy.This review summarizes and synthesizes our current knowledge of the canonical Wnt pathway in development and disease.We begin with an overview of the components of the canonical Wnt signaling pathway and delve into the role this pathway has been shown to play in stemness,tumorigenesis,and cancer drug resistance.Ultimately,we hope to present an organized collection of evidence implicating Wnt signaling in tumorigenesis and chemoresistance to facilitate the pursuit of Wnt pathway modulators that may improve outcomes of cancers in which Wnt signaling contributes to aggressive disease and/or treatment resistance.
基金support from National Mega-project for Innovative Drugs(grant number 2019ZX09721001-004-007,China)National Natural Science Foundation of China(NSFC,grant numbers U1803122,81773637,81773594,and U1703111)the Fundamental Research Fund for the Central Universities(HUST COVID-19 Rapid Response Call,No.2020kfyXGYJ037,China)
文摘SARS-CoV-2 has caused tens of thousands of infections and more than one thousand deaths.There are currently no registered therapies for treating coronavirus infections.Because of time consuming process of new drug development,drug repositioning may be the only solution to the epidemic of sudden infectious diseases.We systematically analyzed all the proteins encoded by SARS-CoV-2 genes,compared them with proteins from other coronavirnses,predicted their structures,and built 19 structures that could be done by homology modeling.By performing target-based virtual ligand screening,a total of21 targets(including two human targets)were screened against compound libraries including ZINC drug database and our own database of natural products.Structure and screening results of important targets such as 3-chymotrypsin-like protease(3 CLpro),Spike,RNA-dependent RNA polymerase(RdRp),and papain like protease(PLpro)were discussed in detail.In addition,a database of 78 commonly used antiviral drugs including those currently on the market and undergoing clinical trials for SARS-CoV-2 was constructed.Possible targets of these compounds and potential drugs acting on a certain target were predicted.This study will provide new lead compounds and targets for further in vitro and in vivo studies of SARS-CoV-2,new insights for those drugs currently ongoing clinical studies,and also possible new strategies for drug repositioning to treat SARS-CoV-2 infections.
基金Supported by Partially funded by the Carlos Ⅲ Health Institute No.PI11/01593
文摘Colorectal cancer(CRC)is a very heterogeneous disease that is caused by the interaction of genetic and environmental factors.CRC develops through a gradual accumulation of genetic and epigenetic changes,leading to the transformation of normal colonic mucosa into invasive cancer.CRC is one of the most prevalent and incident cancers worldwide,as well as one of the most deadly.Approximately 1235108 people are diagnosed annually with CRC,and 609051 die from CRC annually.The World Health Organization estimates an increase of77%in the number of newly diagnosed cases of CRCand an increase of 80%in deaths from CRC by 2030.The incidence of CRC can benefit from different strategies depending on its stage:health promotion through health education campaigns(when the disease is not yet present),the implementation of screening programs(for detection of the disease in its early stages),and the development of nearly personalized treatments according to both patient characteristics(age,sex)and the cancer itself(gene expression).Although there are different strategies for screening and although the number of such strategies is increasing due to the potential of emerging technologies in molecular marker application,not all strategies meet the criteria required for screening tests in population programs;the three most accepted tests are the fecal occult blood test(FOBT),colonoscopy and sigmoidoscopy.FOBT is the most used method for CRC screening worldwide and is also the primary choice in most population-based screening programs in Europe.Due to its non-invasive nature and low cost,it is one of the most accepted techniques by population.CRC is a very heterogeneous disease,and with a few exceptions(APC,p53,KRAS),most of the genes involved in CRC are observed in a small percentage of cases.The design of genetic and epigenetic marker panels that are able to provide maximum coverage in the diagnosis of colorectal neoplasia seems a reasonable strategy.In recent years,the use of DNA,RNA and protein markers in different biological samples
基金supported by grants from the National Natural Science Foundation of China(81673760 and 81874397).
文摘Epithelial-to-mesenchymal transition(EMT)is implicated in a wide array of malignant behaviors of cancers,including proliferation,invasion,and metastasis.Most notably,previou studies have indicated that both cancer stem-like properties and drug resistance were associated with EMT.Furthermore,microRNAs(miRNAs)play a pivotal role in the regulation of EMT phenotype,as a result,some miRNAs impact cancer stemness and drug resistance.Therefore,understanding the relationship between EMT-associated miRNAs and cancer stemness/drug resistance is beneficial to both basic research and clinical treatment.In this review,we preliminarily looked into the various roles that the EMT-associated miRNAs play in the stem-like nature of malignant cells.Then,we reviewed the interaction between EMT-associated miRNAs and the drugresistant complex signaling pathways of multiple cancers including lung cancer,gastric cancer,gynecologic cancer,breast cancer,liver cancer,colorectal cancer,pancreatic cancer,esophageal cancer,and nasopharyngeal cancer.We finally discussed the relationship between EMT,cancer stemness,and drug resistance,as well as looked forward to the potential applications of miRNA therapy for malignant tumors.
