| BackgroundNeuroendocrine tumors are a general term for a wide range of diseases,which refers to benign and malignant tumors derived from neuroendocrine cells in any part of the body.Neuroendocrine cells spread throughout the body,so neuroendocrine tumors can occur in any part of the body,but the most common is the stomach,intestine,pancreas and other digestive system neuroendocrine tumors,accounting for about 2/3 of all neuroendocrine tumors.Before,the colon’s neuroendocrine tumor incidence is low,so there has been no concern.But in recent years,gastrointestinal endocrine tumors from 25 years ago,0.004%year after year rose,and now up 10 times.Studies have shown that neuroendocrine tumors from the digestive system account for about 55% to 70% of the total neuroendocrine tumors.Unlike other neuroendocrine tumors,gastrointestinal neuroendocrine tumors have special bioactive substances such as serotonin,histamine,and chromogranin.The disease is a cause of concern due to rising prevalence and special clinical manifestations.A total of 35825 cases were analyzed according to the US multicenter.The median age at onset was 65 years.The results of the Japanese study show that the incidence of gastrointestinal neuroendocrine tumors in 2005 was about 2.1 / 104.The most common pathogenesis of colorectal neuroendocrine tumors was mainly located in the rectum(51.08%),the second in the ascending colon(including the cecal 33.04%)in the third sigmoid colon(5.94%),the rest of the site at the junction of straight b(4.54%),Transverse colon(1.88%)and descending colon(1.10%),and about 2.42% can not clear specific parts.At present,China has not yet established a nationwide tumor registration system,can not neuroendocrine tumor epidemiological data authoritative analysis.Surgery for the removal of neuroendocrine tumors is a common treatment to achieve healing.The tumor diameter> 2 cm and violations of the muscle,lymph node metastasis in patients with postoperative recurrence of the tumor prone to local radiotherapy can reduce the risk of local recurrence.In recent years,with the development of tumor targeted therapy,the emergence of targeted drugs to NET treatment has brought new breakthroughs.In recent years,domestic and foreign scholars on the important role of mTOR signaling pathway to give a wide range of attention,the relevant reports are not uncommon,especially in the study of the pathways in the increasingly deep,some studies have come to the conclusion of clinical treatment to play a positive guide effect.It has been described above that the PI3 K / Akt / mTOR signaling pathway plays an important role in the development and progression of the tumor.The Akt factor in this pathway regulates multiple families associated with apoptosis and inhibits cell apoptosis and promotes cell survival.Another upstream factor,PI3 K,can transmit mitotic signaling to downstream factor ribosomal S6 protein kinase(p70S6K)by Akt,m TOR,so that the cell cycle of the major associated proteins such as cyclin,cell cycle-dependent protein kinase 4(CDK4)Up-regulation,while CDK4 inhibition of p2 laPl and other expression,to promote the progress of Gl phase,the cell cycle to accelerate and promote cell proliferation and differentiation,thereby promoting the occurrence and development of the tumor.The activated P13 K / Akt pathway can upregulate HIF-1d by a variety of ways,promote the expression of vascular endothelial growth factor(VEGF),promote angiogenesis,and increase blood supply for tumor cells.P70S6 K is one of the downstream proteins of mTOR,which can promote the cell movement after activation.Activated Akt can also increase the transcriptional activity of NF-κB(NF-κB),increase the motor function of tumor cells and contribute to the invasion of cancer cells.At the same time,the P13 K / Akt / mTOR pathway also up-regulates the expression of matrix metalloproteinase-2(MMP-2)mRNA and protein and promotes the metastasis of tumor cells.It can be seen that the activated P13 K / Akt / mTOR signaling pathway can inhibit cell apoptosis,accelerate cell cycle progression,and promote cell growth and proliferation,while participating in angiogenesis,and participate in tumor invasion and metastasis in tumor formation and Play a very important role in the development.Ivanomycin is a derivative of sirolimus,a kinase that interferes with cell communication to prevent the growth of tumor cells.It is an oral mammalian rapamycin(mTOR)inhibitor,which has been used primarily for the prevention of kidney Transplantation and rejection after cardiac transplantation.It can also be used to treat patients with advanced renal cell carcinoma who have used two inhibitors of vascular endothelial growth factor receptor kinase inhibitors sunitinib(Sutent,Pfizer)and sorafenib(Nexavar,Bayer)Slightly minor.Sunitinib and sorafenib are a variety of kinase inhibitors(acting on a variety of cell targets),while everolimus blocks specific mammalian rapamycin target(mTOR)specific proteins,Cancer cell growth,differentiation and metabolism.Epirastine binds to intracellular protein FKBP-12 to form a suppressor complex that inhibits mTOR kinase activity while reducing mTOR downstream effector S6 ribosomal protein kinase(S6K1)and eukaryotic elongation factor 4E binding protein(4E-BP)activity.In addition,everolimus inhibits the expression of hypoxia-inducible factors(such as HIF-1)and decreases the expression of vascular endothelial growth factor(VEGF).In vitro and in vivo studies have shown that cell proliferation,angiogenesis and glucose uptake can be reduced.ObjectiveThe expression of mTOR pathway-related protein,Ki-67 and Caspase-3 were detected in clinical specimens and cell lines of neuroendocrine tumors.The effects of everolimus were observed and the effect of everolimus was observed.Treatment of neuroendocrine tumors involved in the mechanism of autophagy,and neuroendocrine tumor treatment to provide a new direction.MehtodsFrom August 2011 to August 2015,244 patients with neuroendocrine tumors hospitalized at the First Affiliated Hospital of Soochow University were included in the study.244 patients were randomly divided into control group(no everolimus treatment)and everolimus group.All patients were diagnosed by clinical pathology and described in previous studies to exclude non-neuroendocrine tumors,and all patients had complete clinical data.112 males and 132 females,aged 20 to 80 years,mean age 47.5 years.According to the World Health Organization in 2014 released NETs six standard,there are28 primary 36 cases,64 cases of secondary,64 cases of Grade 3,40 cases of 40 cases,40 cases of Grade 5 and 36 cases of six levels.The experimental program has been approved by the Ethics Committee of the First Affiliated Hospital of Suzhou University and obtained written consent from patients and healthy volunteers.The expression of Ki67 and caspase-3 was detected by immunohistochemistry,RT-PCR and western blot.And the cell proliferation of the neuroendocrine tumor cell line BON was carried out by MTT and western blot at the cellular level.The mechanism of mTOR signaling pathway andautophagy was discussed.Results1.Ki67 positive for the nucleus purple or purple brown parts,which can be found in the neuroendocrine tumor tissue,Ki67 expression was significantly increased.At the same time,the mRNA level and protein level of tumor tissue were detected,and the same results were obtained.Ki67 was highly expressed in tumor tissue.2.In Ki67 expression and tumor grade correlation analysis can be found,lower grade Ki67 expression higher.3.Caspase-3 positive for the nucleus red or purple parts,which can be found in the neuroendocrine tumor tissue,caspase-3 expression was significantly reduced.At the same time,the mRNA level and protein level of tumor tissue were detected,and the same result was obtained.The expression of caspase-3 was low in tumor tissue.4.In caspase-3 expression and tumor grading correlation analysis can be found,higher grading caspase-3 expression higher5.In the tumor tissue treated with everolimus,the mRNA and protein levels of Ki67 were significantly higher than those of adjacent tissues.After intervention with everolimus,the Ki67 mRNA and protein The level of change with the adjacent tissue is not changed6.In the detection of caspase-3,it was found that the mRNA and protein levels of caspase-3 were significantly lower than those in the adjacent tissues,but the patients were treated with everolimus,The tumor tissue caspase-3 mRNA and protein levels compared with the adjacent tissue is not much change7.BON cells were treated with everolimus 10 nM,and the cell proliferation was significantly inhibited after 24 h compared with those without intervention.There was a statistically significant difference between the two groups.8.The levels of mTOR,p70S6 K and 4EBP1 phosphorylation of mTOR signaling pathway were inhibited and the mTOR signal pathway was inhibited after 10 nM intervention.The results were consistent with the everolimus mTOR signaling pathway inhibitor.9.The level of protein expression of autophagy-related molecules LC3Ⅱ and beclin was significantly increased after iemethasone 10 nM intervention.Conclusion1.Everolimus has a significant inhibitory effect on neuroendocrine tumors,both at the human level and at the cellular level.2.May inhibit the mTOR signal pathway,induced tumor cell autophagy,promote cell apoptosis and inhibit cell proliferation.3.MTOR signaling pathway can be used as a new target for the treatment of neuroendocrine tumors,providing new ideas and theoretical basis for the treatment of neuroendocrine tumors. |
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