Objective Our previous studies established that microRNA(miR)-451 from human umbilical cord mesenchymal stem cell-derived exosomes(hUC-MSC-Exos)alleviates acute lung injury(ALI).This study aims to elucidate the mechan...Objective Our previous studies established that microRNA(miR)-451 from human umbilical cord mesenchymal stem cell-derived exosomes(hUC-MSC-Exos)alleviates acute lung injury(ALI).This study aims to elucidate the mechanisms by which miR-451 in hUC-MSC-Exos reduces ALI by modulating macrophage autophagy.Methods Exosomes were isolated from hUC-MSCs.Severe burn-induced ALI rat models were treated with hUC-MSC-Exos carrying the miR-451 inhibitor.Hematoxylin-eosin staining evaluated inflammatory injury.Enzyme-linked immunosorbnent assay measured lipopolysaccharide(LPS),tumor necrosis factor-α,and interleukin-1βlevels.qRT-PCR detected miR-451 and tuberous sclerosis complex 1(TSC1)expressions.The regulatory role of miR-451 on TSC1 was determined using a dual-luciferase reporter system.Western blotting determined TSC1 and proteins related to the mammalian target of rapamycin(mTOR)pathway and autophagy.Immunofluorescence analysis was conducted to examine exosomes phagocytosis in alveolar macrophages and autophagy level.Results hUC-MSC-Exos with miR-451 inhibitor reduced burn-induced ALI and promoted macrophage autophagy.MiR-451 could be transferred from hUC-MSCs to alveolar macrophages via exosomes and directly targeted TSC1.Inhibiting miR-451 in hUC-MSC-Exos elevated TSC1 expression and inactivated the mTOR pathway in alveolar macrophages.Silencing TSC1 activated mTOR signaling and inhibited autophagy,while TSC1 knockdown reversed the autophagy from the miR-451 inhibitor-induced.Conclusion miR-451 from hUC-MSC exosomes improves ALI by suppressing alveolar macrophage autophagy through modulation of the TSC1/mTOR pathway,providing a potential therapeutic strategy for ALI.展开更多
BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors.Osteopontin(OPN)is thought to be closely related to the occurrence,metastasis and prognosis of many types of tumors.AIM To investigate the effect...BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors.Osteopontin(OPN)is thought to be closely related to the occurrence,metastasis and prognosis of many types of tumors.AIM To investigate the effects of OPN on the proliferation,invasion and migration of GC cells and its possible mechanism.METHODS The mRNA and protein expression of OPN in the GC cells were analyzed by realtime quantitative-reverse transcription polymerase chain reaction and western blotting,and observe the effect of varying degree expression OPN on the proliferation and other behaviors of GC.Next,the effects of OPN knockdown on GC cells migration and invasion were examined.The short hairpin RNA(shRNA)and negative control shRNA targeting OPN-shRNA were transfected into the cells according to the manufacturer’s instructions.Non transfected cells were classified as control in the identical transfecting process.24 h after RNA transfection cell proliferation activity was detected by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide assay,and cell invasiveness and migration were detected by Trans well assay.Meanwhile,the expression of protein kinase B(AKT),matrix metalloproteinase 2(MMP-2)and vascular endothelial growth factor(VEGF)in the human GC cell lines was detected by reverse transcription polymerase chain reaction and western blotting.RESULTS The results of this study revealed that OPN mRNA and protein expression levels were highly expressed in SGC-7901 cells.OPN knockdown by specific shRNA noticeably reduced the capabilities of proliferation,invasion and migration of SGC-7901 cells.Moreover,in the experiments of investigating the underlying mechanism,results showed that OPN knockdown could down-regulated the expression of MMP-2 and VEGF,it also decreased the phosphorylation of AKT.Meanwhile,the protein expression levels of MMP-2,VEGF and phosphorylated AKT was noticeable lower than that in control group in the GC cells after they were added to phosphatidylinositol-3-kinase(PI3K)inhibitor(LY294002).CONCLUSION These results suggested that OPN though PI3K/AKT/mammalian target of rapamycin signal pathway to upregulate MMP-2 and VEGF expression,which contribute SGC-7901 cells to proliferation,invasion and migration.Thus,our results demonstrate that OPN may serve as a novel prognostic biomarkers as well as a potential therapeutic targets for GC.展开更多
Background:Oral squamous cell carcinoma(OSCC)is a common malignant tumor.Recently,Laminin Gamma 2(LAMC2)has been shown to be abnormally expressed in OSCC;however,how LAMC2 signaling contributes to the occurrence and d...Background:Oral squamous cell carcinoma(OSCC)is a common malignant tumor.Recently,Laminin Gamma 2(LAMC2)has been shown to be abnormally expressed in OSCC;however,how LAMC2 signaling contributes to the occurrence and development of OSCC and the role of autophagy in OSCC has not been fully explored.This study aimed to analyze the role and mechanism of LAMC2 signaling in OSCC and the involvement of autophagy in OSCC.Methods:To explore the mechanism by which LAMC2 is highly expressed in OSCC,we used small interfering RNA(siRNA)to knock down LAMC2 to further observe the changes in the signaling pathway.Furthermore,we used cell proliferation assays,Transwell invasion assays,and wound-healing assays to observe the changes in OSCC proliferation,invasion,and metastasis.RFP-LC3 was used to detect the level of autophagy intensity.A cell line-derived xenograft(CDX)model was used to detect the effect of LAMC2 on tumor growth in vivo.Results:This study found that the level of autophagy was correlated with the biological behavior of OSCC.The downregulation of LAMC2 activated autophagy and inhibited OSCC proliferation,invasion,and metastasis via inhibiting the PI3K/AKT/mTOR pathway.Moreover,autophagy has a dual effect on OSCC,and the synergistic downregulation of LAMC2 and autophagy can inhibit OSCC metastasis,invasion,and proliferation via the PI3K/AKT/mTOR pathway.Conclusions:LAMC2 interacts with autophagy to regulate OSCC metastasis,invasion,and proliferation via the PI3K/AKT/mTOR pathway.LAMC2 down-regulation can synergistically modulate autophagy to inhibit OSCC migration,invasion,and proliferation.展开更多
The mammalian target of rapamycin （mTOR） pathway plays an important role in neuronal growth, proliferation and differentiation. To better understand the role of mTOR pathway involved in the induction of spinal cord ...The mammalian target of rapamycin （mTOR） pathway plays an important role in neuronal growth, proliferation and differentiation. To better understand the role of mTOR pathway involved in the induction of spinal cord injury, rat models of spinal cord injury were established by modified Allen＇s stall method and interfered for 7 days by intraperitoneal administration of mTOR activator adenosine triphosphate and mTOR kinase inhibitor rapamycin. At 1-4 weeks after spinal cord injury induction, the Basso, Beattie and Bresnahan locomotor rating scale was used to evaluate rat locomotor function, and immunohistochemical staining and western blot analysis were used to detect the expression of nestin （neural stem cell marker）, neuronal nuclei （neuronal marker）, neuron specific enolase, neurofilament protein 200 （axonal marker）, glial fibrillary acidic protein （astrocyte marker）, Akt, mTOR and signal transduction and activator of transcription 3 （STAT3）. Results showed that adenosine triphosphate-mediated Akt/mTOR/STAT3 pathway increased endogenous neural stem cells, induced neurogenesis and axonal growth, inhibited excessive astrogliosis and improved the locomotor function of rats with spinal cord injury.展开更多
Objective: To study the changes of PI3K/AKT/mTOR signaling pathway in the progression of cervical cancer and explore its target genes. Methods: The patients who underwent surgical resection and were diagnosed with cer...Objective: To study the changes of PI3K/AKT/mTOR signaling pathway in the progression of cervical cancer and explore its target genes. Methods: The patients who underwent surgical resection and were diagnosed with cervical cancer by postoperative pathology in the First People's Hospital of Jiangxia District Wuhan City between June 2014 and December 2017 were selected, and the cervical cancer lesion tissues and lesion tissues adjacent to cervical cancer were kept;patients who underwent conization and were diagnosed with cervical intraepithelial neoplasia by postoperative pathology in the First People's Hospital of Jiangxia District Wuhan City during the same period were selected, and the cervical intraepithelial neoplasia tissues were kept. The protein levels of PI3K/AKT/mTOR signaling molecules as well as the mRNA expression of proliferation genes and invasion genes were determined. Results: p-PI3K, p-AKT, mTOR, p70S6K and p-4EBP1 protein levels as well as CyclinD1, Survivin, Piwil2, RACK1, EFEMP1 and VEGF mRNA expression in cervical cancer lesion tissues were significantly higher than those in adjacent lesion tissues and cervical intraepithelial neoplasia tissues whereas THBS2, Beclin1, E-cadherin, TIMP1 and TIMP2 mRNA expression were significantly lower than those in adjacent lesion tissues and cervical intraepithelial neoplasia tissues;p-PI3K, p-AKT, mTOR, p70S6K and p-4EBP1 protein levels in cervical cancer lesion tissues were positively correlated with CyclinD1, Survivin, Piwil2, RACK1, EFEMP1 and VEGF mRNA expression, and negatively correlated with THBS2, Beclin1, E-cadherin, TIMP1 and TIMP2 mRNA expression. Conclusion: Excessive activation of PI3K/AKT/mTOR signaling pathway during the progression of cervical cancer can change the expression of multiple proliferation and invasion genes to promote the proliferation and invasion of cancer cells.展开更多
多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是一组生殖内分泌代谢紊乱的综合征,临床以稀发排卵、高雄激素体征、胰岛素抵抗为主要特征,其中育龄期发病率高,对女性生育力造成严重不良影响。PCOS的发生发展涉及多种信号通路,腺苷酸...多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是一组生殖内分泌代谢紊乱的综合征,临床以稀发排卵、高雄激素体征、胰岛素抵抗为主要特征,其中育龄期发病率高,对女性生育力造成严重不良影响。PCOS的发生发展涉及多种信号通路,腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)及哺乳动物雷帕霉素靶蛋白(Mammalian target of rapamycin,mTOR)作为细胞能量感受器是其中两个关键靶点。二者在PCOS各个发病部位包括下丘脑-垂体-卵巢轴、子宫内膜、脂肪与骨骼肌中发挥重要的调节作用,通过影响细胞自噬、氧化应激、炎症、线粒体功能、葡萄糖摄取等,促进卵泡的发育和成熟,改善胰岛素抵抗。近年来,中医药因其成分多样、靶点众多等优势广泛应用于临床,研究人员已对PCOS的发病以及中药治疗及改善PCOS的机制进行了大量研究,结果提示AMPK与mTOR相关通路在其中发挥关键作用。通过总结中药干预AMPK与mTOR及其相关通路治疗PCOS的研究结果,为临床治疗及基础研究提供参考。展开更多
Hepatocellular carcinoma(HCC) is one of the leading causes of cancer-related death worldwide. It is associated with a poor prognosis and has limited treatment options. Sorafenib, a multi-targeted kinase inhibitor, is ...Hepatocellular carcinoma(HCC) is one of the leading causes of cancer-related death worldwide. It is associated with a poor prognosis and has limited treatment options. Sorafenib, a multi-targeted kinase inhibitor, is the only available systemic agent for treatment of HCC that improves overall survival for patients with advanced stage disease; unfortunately, an effective second-line agent for the treatment of progressive or sorafenib-resistant HCC has yet to be identified. This review focuses on components of the mammalian target of rapamycin(mTOR) pathway, its role in HCC pathogenesis, and dual mTOR inhibition as a therapeutic option with potential efficacy in advanced HCC. There are several important upstream and downstream signals in the mTOR pathway, and alternative tumor-promoting pathways are known to exist beyond mTORC1 inhibition in HCC. This review analyzes the relationships of the upstream and downstream regulators of mTORC1 and mTORC2 signaling; it also provides a comprehensive global picture of the interaction between mTORC1 and mTORC2 which demonstrates the pre-clinical relevance of the mTOR pathway in HCC pathogenesis and progression. Finally, it provides scientific rationale for dual mTORC1 and mTORC2 inhibition in the treatment of HCC. Clinical trials utilizing mTORC1 inhibitors and dual mTOR inhibitors in HCC are discussed as well. The mTOR pathway is comprised of two main components, mTORC1 and mTORC2; each has a unique role in the pathogenesis and progression of HCC. In phase Ⅲ studies, mTORC1 inhibitors demonstrate anti-tumor ac-tivity in advanced HCC, but dual mTOR(mTORC1 and mTORC2) inhibition has greater therapeutic potential in HCC treatment which warrants further clinical investigation.展开更多
Cancer after transplantation is the third cause of death and one of the more relevant comorbidities. Aim of this review is to verify the role of different pathogenetic mechanisms in cancer development in transplant pa...Cancer after transplantation is the third cause of death and one of the more relevant comorbidities. Aim of this review is to verify the role of different pathogenetic mechanisms in cancer development in transplant patients and in general population as well. In particular has been outlined the different role exerted by two different families of drug as calcineurin inhibitor and mammalian target of rapamycin(m TOR) inhibitor. The role of m TOR pathways in cell homeostasis is complex but enough clear. As a consequence the m TOR pathway deregulation is involved in the genesis of several cancers. Hence the relevant role of m TOR inhibitors. The authors review the complex mechanism of action of m TOR inhibitors, not only for what concerns the immune system but also other cells as endothelial, smooth muscle and epithelial cells. The mechanism of action is still now not completely defined and understood. It implies the inhibition of m TOR pathway at different levels, but mainly at level of the phosphorylation of several intracellular kinases that contribute to activate m TOR complex. Many prospective and retrospective studies in transplant patients document the antineoplastic role of m TOR inhibition. More recently m TOR inhibitors proven to be effective in the treatment of some cancers also in general population. Kidney cancers, neuroendocrine tumors and liver cancers seem to be the most sensitive to these drugs. Best results are obtained with a combination treatment, targeting the m TOR pathway at different levels.展开更多
基金supported by the tenth batch of"3221"industrial innovation and scientific research projects in Bengbu City(beng talent[2020]No.8)the 2021 Bengbu Medical College Science and Technology Project[Natural Science,Project Number:2021byzd217].
文摘Objective Our previous studies established that microRNA(miR)-451 from human umbilical cord mesenchymal stem cell-derived exosomes(hUC-MSC-Exos)alleviates acute lung injury(ALI).This study aims to elucidate the mechanisms by which miR-451 in hUC-MSC-Exos reduces ALI by modulating macrophage autophagy.Methods Exosomes were isolated from hUC-MSCs.Severe burn-induced ALI rat models were treated with hUC-MSC-Exos carrying the miR-451 inhibitor.Hematoxylin-eosin staining evaluated inflammatory injury.Enzyme-linked immunosorbnent assay measured lipopolysaccharide(LPS),tumor necrosis factor-α,and interleukin-1βlevels.qRT-PCR detected miR-451 and tuberous sclerosis complex 1(TSC1)expressions.The regulatory role of miR-451 on TSC1 was determined using a dual-luciferase reporter system.Western blotting determined TSC1 and proteins related to the mammalian target of rapamycin(mTOR)pathway and autophagy.Immunofluorescence analysis was conducted to examine exosomes phagocytosis in alveolar macrophages and autophagy level.Results hUC-MSC-Exos with miR-451 inhibitor reduced burn-induced ALI and promoted macrophage autophagy.MiR-451 could be transferred from hUC-MSCs to alveolar macrophages via exosomes and directly targeted TSC1.Inhibiting miR-451 in hUC-MSC-Exos elevated TSC1 expression and inactivated the mTOR pathway in alveolar macrophages.Silencing TSC1 activated mTOR signaling and inhibited autophagy,while TSC1 knockdown reversed the autophagy from the miR-451 inhibitor-induced.Conclusion miR-451 from hUC-MSC exosomes improves ALI by suppressing alveolar macrophage autophagy through modulation of the TSC1/mTOR pathway,providing a potential therapeutic strategy for ALI.
文摘BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors.Osteopontin(OPN)is thought to be closely related to the occurrence,metastasis and prognosis of many types of tumors.AIM To investigate the effects of OPN on the proliferation,invasion and migration of GC cells and its possible mechanism.METHODS The mRNA and protein expression of OPN in the GC cells were analyzed by realtime quantitative-reverse transcription polymerase chain reaction and western blotting,and observe the effect of varying degree expression OPN on the proliferation and other behaviors of GC.Next,the effects of OPN knockdown on GC cells migration and invasion were examined.The short hairpin RNA(shRNA)and negative control shRNA targeting OPN-shRNA were transfected into the cells according to the manufacturer’s instructions.Non transfected cells were classified as control in the identical transfecting process.24 h after RNA transfection cell proliferation activity was detected by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide assay,and cell invasiveness and migration were detected by Trans well assay.Meanwhile,the expression of protein kinase B(AKT),matrix metalloproteinase 2(MMP-2)and vascular endothelial growth factor(VEGF)in the human GC cell lines was detected by reverse transcription polymerase chain reaction and western blotting.RESULTS The results of this study revealed that OPN mRNA and protein expression levels were highly expressed in SGC-7901 cells.OPN knockdown by specific shRNA noticeably reduced the capabilities of proliferation,invasion and migration of SGC-7901 cells.Moreover,in the experiments of investigating the underlying mechanism,results showed that OPN knockdown could down-regulated the expression of MMP-2 and VEGF,it also decreased the phosphorylation of AKT.Meanwhile,the protein expression levels of MMP-2,VEGF and phosphorylated AKT was noticeable lower than that in control group in the GC cells after they were added to phosphatidylinositol-3-kinase(PI3K)inhibitor(LY294002).CONCLUSION These results suggested that OPN though PI3K/AKT/mammalian target of rapamycin signal pathway to upregulate MMP-2 and VEGF expression,which contribute SGC-7901 cells to proliferation,invasion and migration.Thus,our results demonstrate that OPN may serve as a novel prognostic biomarkers as well as a potential therapeutic targets for GC.
基金This work was supported by the National Natural Science Foundation of China(Grant Numbers 31971106,BWS21L013,21WS09002,JK20211A010213).
文摘Background:Oral squamous cell carcinoma(OSCC)is a common malignant tumor.Recently,Laminin Gamma 2(LAMC2)has been shown to be abnormally expressed in OSCC;however,how LAMC2 signaling contributes to the occurrence and development of OSCC and the role of autophagy in OSCC has not been fully explored.This study aimed to analyze the role and mechanism of LAMC2 signaling in OSCC and the involvement of autophagy in OSCC.Methods:To explore the mechanism by which LAMC2 is highly expressed in OSCC,we used small interfering RNA(siRNA)to knock down LAMC2 to further observe the changes in the signaling pathway.Furthermore,we used cell proliferation assays,Transwell invasion assays,and wound-healing assays to observe the changes in OSCC proliferation,invasion,and metastasis.RFP-LC3 was used to detect the level of autophagy intensity.A cell line-derived xenograft(CDX)model was used to detect the effect of LAMC2 on tumor growth in vivo.Results:This study found that the level of autophagy was correlated with the biological behavior of OSCC.The downregulation of LAMC2 activated autophagy and inhibited OSCC proliferation,invasion,and metastasis via inhibiting the PI3K/AKT/mTOR pathway.Moreover,autophagy has a dual effect on OSCC,and the synergistic downregulation of LAMC2 and autophagy can inhibit OSCC metastasis,invasion,and proliferation via the PI3K/AKT/mTOR pathway.Conclusions:LAMC2 interacts with autophagy to regulate OSCC metastasis,invasion,and proliferation via the PI3K/AKT/mTOR pathway.LAMC2 down-regulation can synergistically modulate autophagy to inhibit OSCC migration,invasion,and proliferation.
文摘The mammalian target of rapamycin （mTOR） pathway plays an important role in neuronal growth, proliferation and differentiation. To better understand the role of mTOR pathway involved in the induction of spinal cord injury, rat models of spinal cord injury were established by modified Allen＇s stall method and interfered for 7 days by intraperitoneal administration of mTOR activator adenosine triphosphate and mTOR kinase inhibitor rapamycin. At 1-4 weeks after spinal cord injury induction, the Basso, Beattie and Bresnahan locomotor rating scale was used to evaluate rat locomotor function, and immunohistochemical staining and western blot analysis were used to detect the expression of nestin （neural stem cell marker）, neuronal nuclei （neuronal marker）, neuron specific enolase, neurofilament protein 200 （axonal marker）, glial fibrillary acidic protein （astrocyte marker）, Akt, mTOR and signal transduction and activator of transcription 3 （STAT3）. Results showed that adenosine triphosphate-mediated Akt/mTOR/STAT3 pathway increased endogenous neural stem cells, induced neurogenesis and axonal growth, inhibited excessive astrogliosis and improved the locomotor function of rats with spinal cord injury.
文摘Objective: To study the changes of PI3K/AKT/mTOR signaling pathway in the progression of cervical cancer and explore its target genes. Methods: The patients who underwent surgical resection and were diagnosed with cervical cancer by postoperative pathology in the First People's Hospital of Jiangxia District Wuhan City between June 2014 and December 2017 were selected, and the cervical cancer lesion tissues and lesion tissues adjacent to cervical cancer were kept;patients who underwent conization and were diagnosed with cervical intraepithelial neoplasia by postoperative pathology in the First People's Hospital of Jiangxia District Wuhan City during the same period were selected, and the cervical intraepithelial neoplasia tissues were kept. The protein levels of PI3K/AKT/mTOR signaling molecules as well as the mRNA expression of proliferation genes and invasion genes were determined. Results: p-PI3K, p-AKT, mTOR, p70S6K and p-4EBP1 protein levels as well as CyclinD1, Survivin, Piwil2, RACK1, EFEMP1 and VEGF mRNA expression in cervical cancer lesion tissues were significantly higher than those in adjacent lesion tissues and cervical intraepithelial neoplasia tissues whereas THBS2, Beclin1, E-cadherin, TIMP1 and TIMP2 mRNA expression were significantly lower than those in adjacent lesion tissues and cervical intraepithelial neoplasia tissues;p-PI3K, p-AKT, mTOR, p70S6K and p-4EBP1 protein levels in cervical cancer lesion tissues were positively correlated with CyclinD1, Survivin, Piwil2, RACK1, EFEMP1 and VEGF mRNA expression, and negatively correlated with THBS2, Beclin1, E-cadherin, TIMP1 and TIMP2 mRNA expression. Conclusion: Excessive activation of PI3K/AKT/mTOR signaling pathway during the progression of cervical cancer can change the expression of multiple proliferation and invasion genes to promote the proliferation and invasion of cancer cells.
文摘多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是一组生殖内分泌代谢紊乱的综合征,临床以稀发排卵、高雄激素体征、胰岛素抵抗为主要特征,其中育龄期发病率高,对女性生育力造成严重不良影响。PCOS的发生发展涉及多种信号通路,腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)及哺乳动物雷帕霉素靶蛋白(Mammalian target of rapamycin,mTOR)作为细胞能量感受器是其中两个关键靶点。二者在PCOS各个发病部位包括下丘脑-垂体-卵巢轴、子宫内膜、脂肪与骨骼肌中发挥重要的调节作用,通过影响细胞自噬、氧化应激、炎症、线粒体功能、葡萄糖摄取等,促进卵泡的发育和成熟,改善胰岛素抵抗。近年来,中医药因其成分多样、靶点众多等优势广泛应用于临床,研究人员已对PCOS的发病以及中药治疗及改善PCOS的机制进行了大量研究,结果提示AMPK与mTOR相关通路在其中发挥关键作用。通过总结中药干预AMPK与mTOR及其相关通路治疗PCOS的研究结果,为临床治疗及基础研究提供参考。
文摘Hepatocellular carcinoma(HCC) is one of the leading causes of cancer-related death worldwide. It is associated with a poor prognosis and has limited treatment options. Sorafenib, a multi-targeted kinase inhibitor, is the only available systemic agent for treatment of HCC that improves overall survival for patients with advanced stage disease; unfortunately, an effective second-line agent for the treatment of progressive or sorafenib-resistant HCC has yet to be identified. This review focuses on components of the mammalian target of rapamycin(mTOR) pathway, its role in HCC pathogenesis, and dual mTOR inhibition as a therapeutic option with potential efficacy in advanced HCC. There are several important upstream and downstream signals in the mTOR pathway, and alternative tumor-promoting pathways are known to exist beyond mTORC1 inhibition in HCC. This review analyzes the relationships of the upstream and downstream regulators of mTORC1 and mTORC2 signaling; it also provides a comprehensive global picture of the interaction between mTORC1 and mTORC2 which demonstrates the pre-clinical relevance of the mTOR pathway in HCC pathogenesis and progression. Finally, it provides scientific rationale for dual mTORC1 and mTORC2 inhibition in the treatment of HCC. Clinical trials utilizing mTORC1 inhibitors and dual mTOR inhibitors in HCC are discussed as well. The mTOR pathway is comprised of two main components, mTORC1 and mTORC2; each has a unique role in the pathogenesis and progression of HCC. In phase Ⅲ studies, mTORC1 inhibitors demonstrate anti-tumor ac-tivity in advanced HCC, but dual mTOR(mTORC1 and mTORC2) inhibition has greater therapeutic potential in HCC treatment which warrants further clinical investigation.
文摘Cancer after transplantation is the third cause of death and one of the more relevant comorbidities. Aim of this review is to verify the role of different pathogenetic mechanisms in cancer development in transplant patients and in general population as well. In particular has been outlined the different role exerted by two different families of drug as calcineurin inhibitor and mammalian target of rapamycin(m TOR) inhibitor. The role of m TOR pathways in cell homeostasis is complex but enough clear. As a consequence the m TOR pathway deregulation is involved in the genesis of several cancers. Hence the relevant role of m TOR inhibitors. The authors review the complex mechanism of action of m TOR inhibitors, not only for what concerns the immune system but also other cells as endothelial, smooth muscle and epithelial cells. The mechanism of action is still now not completely defined and understood. It implies the inhibition of m TOR pathway at different levels, but mainly at level of the phosphorylation of several intracellular kinases that contribute to activate m TOR complex. Many prospective and retrospective studies in transplant patients document the antineoplastic role of m TOR inhibition. More recently m TOR inhibitors proven to be effective in the treatment of some cancers also in general population. Kidney cancers, neuroendocrine tumors and liver cancers seem to be the most sensitive to these drugs. Best results are obtained with a combination treatment, targeting the m TOR pathway at different levels.
