The term“undruggable”is to describe molecules that are not targetable or at least hard to target pharmacologically.Unfortunately,some targets with potent oncogenic activity fall into this category,and currently litt...The term“undruggable”is to describe molecules that are not targetable or at least hard to target pharmacologically.Unfortunately,some targets with potent oncogenic activity fall into this category,and currently little is known about how to solve this problem,which largely hampered drug research on human cancers.Ras,as one of the most common oncogenes,was previously considered“undruggable”,but in recent years,a few small molecules like Sotorasib(AMG-510)have emerged and proved their targeted anti-cancer effects.Further,myc,as one of the most studied oncogenes,and tp53,being the most common tumor suppressor genes,are both considered“undruggable”.Many attempts have been made to target these“undruggable”targets,but little progress has been made yet.This article summarizes the current progress of direct and indirect targeting approaches for ras,myc,two oncogenes,and tp53,a tumor suppressor gene.These are potential therapeutic targets but are considered“undruggable”.We conclude with some emerging research approaches like proteolysis targeting chimeras(PROTACs),cancer vaccines,and artificial intelligence(AI)-based drug discovery,which might provide new cues for cancer intervention.Therefore,this review sets out to clarify the current status of targeted anti-cancer drug research,and the insights gained from this review may be of assistance to learn from experience and find new ideas in developing new chemicals that directly target such“undruggable”molecules.展开更多
INTRODUCTIONThe esophageal carcinoma is a common malignanttumor in Linzhou City (Linxian) of Henan Provincein northern China.Although the etiology andnatural history of csophageal carcinoma are notclear,a substantial ...INTRODUCTIONThe esophageal carcinoma is a common malignanttumor in Linzhou City (Linxian) of Henan Provincein northern China.Although the etiology andnatural history of csophageal carcinoma are notclear,a substantial amount of evidence has beenprovided to suggest that the development of humanesophageal squamous cell carcinomas (SCC) is amultistage progressive process.An展开更多
AIM To evaluate the relationship between expression of ras, p53, bcl 2 gene products, and hepatocarcinogenesis since endotoxemia produced from lipopolysaccharide admi nistration and/or the hypophagocytic state of ...AIM To evaluate the relationship between expression of ras, p53, bcl 2 gene products, and hepatocarcinogenesis since endotoxemia produced from lipopolysaccharide admi nistration and/or the hypophagocytic state of splenectomy significantly accelerated hepatocarcinogenesis induced by thioacetamide. 〖WTH4〗METHODS〓〖WTXFZ〗The hepatocarcinoma model was induced by oral intake of 0 03% thioacetamide for six months. During the induction of hepatocarcinoma model, rats were additionally treated with splenectomy and/or lipopolysaccharide administration. The techniques of flow cytometry, immunohistochemistry and immunoelectronmicroscopy were applied to quantitative analysis of the expression of oncogene proteins. RESULTS In this model system, overexpression of ras p21 protein mainly occurred on precancerous cell population or in early stage of hepatocyte transformation. And the levels of ras p21 declined when nuclear DNA aneuploid increased. Expression of bcl 2 protein slowly and steadily rose with more hepatocytes staying in S+G2M phases as the hepatocarcinoma became more malignant. P53 was moderately expressed during the hepatocarcinogenesis. There was no statistical correlation between endotoxemia levels and the changes of ras, p53 and bcl 2 gene products. CONCLUSION Over expression of oncogene ras p21 was likely to be a precursor of the premalignant hepatocytes and it might be responsible for the initiation of hepatocarcinogenesis. Bcl 2 protein expression is proportional to the severity of the malignancies. P53 may be a key pathway on the transformation and development of hepatocarcinoma. This study confirmed the hypothesis that there are multiple genes and multiple steps involved in hepatocarcinogenesis. Expressions of oncogene proteins reflected the properties of the premalignant and malignant cells, but not directly related to endotoxemia statistically.[JP]展开更多
Cdc42 is a member of the Rho subfamily of Ras-related proteins, which were among the first oncogenic proteins to be identified as playing a sig-nificant role in a variety of cellular events [Barbacaid, 1987, Ann. Rev....Cdc42 is a member of the Rho subfamily of Ras-related proteins, which were among the first oncogenic proteins to be identified as playing a sig-nificant role in a variety of cellular events [Barbacaid, 1987, Ann. Rev. Biochem]. Equally important, Protein-Protein Interactions [PPIs] involving Cdc42 continue to highlight the role of Ras-related proteins’ relevance to cancer. As these proteins have been considered incapable of being “druggable”, due to a perceived lack of binding surface[s] that are amenable to small molecule targeting, there remains limited development of therapies to tackle diseased states caused by Cdc42-stimulated hyperactivity. Thusly, it has become important to characterize molecular details, including dynamics, of PPIs involving Cdc42 that may lend themselves as potential targets for therapeutic approaches. Recently, two small molecules, ZCL278 and AZA197, have shown promise in directly targeting Cdc42 to influence PPIs that are capable of causing Cdc42-stimulated abnormal signaling. In this editorial, we highlight recent studies that show case how these two small molecules may influence Cdc42-protein interactions.展开更多
Lung cancer is currently the leading cause of cancer death in Western nations.Non-small cell lung cancer(NSCLC)represents 80%of all lung cancers,and adenocarcinoma is the predominant histological type.Despite the inte...Lung cancer is currently the leading cause of cancer death in Western nations.Non-small cell lung cancer(NSCLC)represents 80%of all lung cancers,and adenocarcinoma is the predominant histological type.Despite the intensive research carried out on this field and therapeutic advances,the overall prognosis of these patients remains unsatisfactory,with a 5-year overall survival rate of less than 15%.Nowadays,pharmacogenetics and pharmacogenomics represent the key to successful treatment.Recent studies suggest the existence of two distinct molecular pathways in the carcinogenesis of lung adenocarcinoma:one associated with smoking and activation of the K-Ras oncogene and the other not associated with smoking and activation of the epidermal growth factor receptor(EGFR).The K-ras mutation is mainly responsible for primary resistance to new molecules which inhibit tyrosine kinase EGFR(erlotinib and gefitinib)and most of the EGFR mutations are responsible for increased tumor sensitivity to these drugs.This article aims to conduct a systematic review of the literature regarding the molecular pathways involving the EGFR,K-Ras and EGFR targeted therapies in NSCLC tumor behavior.展开更多
Alcoholism and acquired immune deficiency syndrome are associated with severe muscle wasting.This impairment in nitrogen balance arises from increased protein degradation and a decreased rate of protein synthesis.The ...Alcoholism and acquired immune deficiency syndrome are associated with severe muscle wasting.This impairment in nitrogen balance arises from increased protein degradation and a decreased rate of protein synthesis.The regulation of protein synthesis is a complex process involving alterations in the phosphorylation state and protein-protein interaction of various components of the translation machinery and mammalian target of rapamycin(mTOR) complexes.This review describes mechanisms that regulate protein synthesis in cultured C2C12 myocytes following exposure to either alcohol or human immunodeficiency virus antiretroviral drugs.Particular attention is given to the upstream regulators of mTOR complexes and the downstream targets which play an important role in translation.Gaining a better understanding of these molecular mechanisms could have important implications for preventing changes in lean body mass in patients with catabolic conditions or illnesses.展开更多
The monoterpene d limonene inhibit the plasma membrane associated P21 ras expression and the posttranslational isoprenylation of P21 ras , a mechanism that may contribute to its efficacy in the chemoprevent...The monoterpene d limonene inhibit the plasma membrane associated P21 ras expression and the posttranslational isoprenylation of P21 ras , a mechanism that may contribute to its efficacy in the chemoprevention and therapy of chemically induced rodent cancers and some human solid tumor cells. In the present study,the relative abilities of d limonene to inhibit membrane associated P21 ras expression in pancreas tumor cell(PaCa) was carried out with Western blotting, and the inhibition of farnesyl protein transferase (FTPase) activity during the Ras protein isoprenylation and cell proliferation were determined.Concomitantly,the effects of d limonene on P21 ras localization by immunohistochemistry and H ras oncogene expression in PaCa tumor cell line by Northern blotting were observed. The results showed that d limonene inhibited FPTase activity, thus to reduce P21H ras isoprenylation. d limonene could decrease P21 ras membrane association and increase cytosolic accumulation of P21 ras . This phenomenon was also noted when d limonene treated PaCa cells were stained immunohistochemically with anti P21 ras antibody. It is suggested that the inhibition of FPTase activity was closely related with the inhibiton of P21 ras membrane association and the alteration of P21 ras localization. Inhibition of farnesylation of P21 ras altered their intracellular localization and, hence, disrupted their biological activity,but no relationship with H ras oncogene expression was found.展开更多
基金supported by Grants from the National Natural Science Foundation of China(81902784)the CAMS Innovation Fund for Medical Sciences(CIFMS,2019-I2M-5-004)+2 种基金the Fund of Sichuan Provincial Department of Science and Technology(2022YFSY0058)the Research Funding(RCDWJS 2020-20)the Research and Development Program(RD-02-202002)from West China School/Hospital of Stomatology Sichuan University.
文摘The term“undruggable”is to describe molecules that are not targetable or at least hard to target pharmacologically.Unfortunately,some targets with potent oncogenic activity fall into this category,and currently little is known about how to solve this problem,which largely hampered drug research on human cancers.Ras,as one of the most common oncogenes,was previously considered“undruggable”,but in recent years,a few small molecules like Sotorasib(AMG-510)have emerged and proved their targeted anti-cancer effects.Further,myc,as one of the most studied oncogenes,and tp53,being the most common tumor suppressor genes,are both considered“undruggable”.Many attempts have been made to target these“undruggable”targets,but little progress has been made yet.This article summarizes the current progress of direct and indirect targeting approaches for ras,myc,two oncogenes,and tp53,a tumor suppressor gene.These are potential therapeutic targets but are considered“undruggable”.We conclude with some emerging research approaches like proteolysis targeting chimeras(PROTACs),cancer vaccines,and artificial intelligence(AI)-based drug discovery,which might provide new cues for cancer intervention.Therefore,this review sets out to clarify the current status of targeted anti-cancer drug research,and the insights gained from this review may be of assistance to learn from experience and find new ideas in developing new chemicals that directly target such“undruggable”molecules.
基金the National Natural Science Foundation of China,No.39840012
文摘INTRODUCTIONThe esophageal carcinoma is a common malignanttumor in Linzhou City (Linxian) of Henan Provincein northern China.Although the etiology andnatural history of csophageal carcinoma are notclear,a substantial amount of evidence has beenprovided to suggest that the development of humanesophageal squamous cell carcinomas (SCC) is amultistage progressive process.An
文摘AIM To evaluate the relationship between expression of ras, p53, bcl 2 gene products, and hepatocarcinogenesis since endotoxemia produced from lipopolysaccharide admi nistration and/or the hypophagocytic state of splenectomy significantly accelerated hepatocarcinogenesis induced by thioacetamide. 〖WTH4〗METHODS〓〖WTXFZ〗The hepatocarcinoma model was induced by oral intake of 0 03% thioacetamide for six months. During the induction of hepatocarcinoma model, rats were additionally treated with splenectomy and/or lipopolysaccharide administration. The techniques of flow cytometry, immunohistochemistry and immunoelectronmicroscopy were applied to quantitative analysis of the expression of oncogene proteins. RESULTS In this model system, overexpression of ras p21 protein mainly occurred on precancerous cell population or in early stage of hepatocyte transformation. And the levels of ras p21 declined when nuclear DNA aneuploid increased. Expression of bcl 2 protein slowly and steadily rose with more hepatocytes staying in S+G2M phases as the hepatocarcinoma became more malignant. P53 was moderately expressed during the hepatocarcinogenesis. There was no statistical correlation between endotoxemia levels and the changes of ras, p53 and bcl 2 gene products. CONCLUSION Over expression of oncogene ras p21 was likely to be a precursor of the premalignant hepatocytes and it might be responsible for the initiation of hepatocarcinogenesis. Bcl 2 protein expression is proportional to the severity of the malignancies. P53 may be a key pathway on the transformation and development of hepatocarcinoma. This study confirmed the hypothesis that there are multiple genes and multiple steps involved in hepatocarcinogenesis. Expressions of oncogene proteins reflected the properties of the premalignant and malignant cells, but not directly related to endotoxemia statistically.[JP]
文摘Cdc42 is a member of the Rho subfamily of Ras-related proteins, which were among the first oncogenic proteins to be identified as playing a sig-nificant role in a variety of cellular events [Barbacaid, 1987, Ann. Rev. Biochem]. Equally important, Protein-Protein Interactions [PPIs] involving Cdc42 continue to highlight the role of Ras-related proteins’ relevance to cancer. As these proteins have been considered incapable of being “druggable”, due to a perceived lack of binding surface[s] that are amenable to small molecule targeting, there remains limited development of therapies to tackle diseased states caused by Cdc42-stimulated hyperactivity. Thusly, it has become important to characterize molecular details, including dynamics, of PPIs involving Cdc42 that may lend themselves as potential targets for therapeutic approaches. Recently, two small molecules, ZCL278 and AZA197, have shown promise in directly targeting Cdc42 to influence PPIs that are capable of causing Cdc42-stimulated abnormal signaling. In this editorial, we highlight recent studies that show case how these two small molecules may influence Cdc42-protein interactions.
文摘Lung cancer is currently the leading cause of cancer death in Western nations.Non-small cell lung cancer(NSCLC)represents 80%of all lung cancers,and adenocarcinoma is the predominant histological type.Despite the intensive research carried out on this field and therapeutic advances,the overall prognosis of these patients remains unsatisfactory,with a 5-year overall survival rate of less than 15%.Nowadays,pharmacogenetics and pharmacogenomics represent the key to successful treatment.Recent studies suggest the existence of two distinct molecular pathways in the carcinogenesis of lung adenocarcinoma:one associated with smoking and activation of the K-Ras oncogene and the other not associated with smoking and activation of the epidermal growth factor receptor(EGFR).The K-ras mutation is mainly responsible for primary resistance to new molecules which inhibit tyrosine kinase EGFR(erlotinib and gefitinib)and most of the EGFR mutations are responsible for increased tumor sensitivity to these drugs.This article aims to conduct a systematic review of the literature regarding the molecular pathways involving the EGFR,K-Ras and EGFR targeted therapies in NSCLC tumor behavior.
基金Supported by National Institute of Health Grants R37 AA-011290and DK-072909
文摘Alcoholism and acquired immune deficiency syndrome are associated with severe muscle wasting.This impairment in nitrogen balance arises from increased protein degradation and a decreased rate of protein synthesis.The regulation of protein synthesis is a complex process involving alterations in the phosphorylation state and protein-protein interaction of various components of the translation machinery and mammalian target of rapamycin(mTOR) complexes.This review describes mechanisms that regulate protein synthesis in cultured C2C12 myocytes following exposure to either alcohol or human immunodeficiency virus antiretroviral drugs.Particular attention is given to the upstream regulators of mTOR complexes and the downstream targets which play an important role in translation.Gaining a better understanding of these molecular mechanisms could have important implications for preventing changes in lean body mass in patients with catabolic conditions or illnesses.
文摘The monoterpene d limonene inhibit the plasma membrane associated P21 ras expression and the posttranslational isoprenylation of P21 ras , a mechanism that may contribute to its efficacy in the chemoprevention and therapy of chemically induced rodent cancers and some human solid tumor cells. In the present study,the relative abilities of d limonene to inhibit membrane associated P21 ras expression in pancreas tumor cell(PaCa) was carried out with Western blotting, and the inhibition of farnesyl protein transferase (FTPase) activity during the Ras protein isoprenylation and cell proliferation were determined.Concomitantly,the effects of d limonene on P21 ras localization by immunohistochemistry and H ras oncogene expression in PaCa tumor cell line by Northern blotting were observed. The results showed that d limonene inhibited FPTase activity, thus to reduce P21H ras isoprenylation. d limonene could decrease P21 ras membrane association and increase cytosolic accumulation of P21 ras . This phenomenon was also noted when d limonene treated PaCa cells were stained immunohistochemically with anti P21 ras antibody. It is suggested that the inhibition of FPTase activity was closely related with the inhibiton of P21 ras membrane association and the alteration of P21 ras localization. Inhibition of farnesylation of P21 ras altered their intracellular localization and, hence, disrupted their biological activity,but no relationship with H ras oncogene expression was found.
