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81.

Background

Glutamine addiction is a hallmark of clear cell renal cell carcinoma (ccRCC); yet whether glutamine metabolism impacts local immune surveillance is unclear. This knowledge may yield novel immunotherapeutic opportunities.

Objective

To seek a potential therapeutic target in glutamine-addicted ccRCC.

Design, setting, and participants

Tumors from ccRCC patients from a Shanghai cohort and ccRCC tumor data from The Cancer Genome Atlas (TCGA) cohort were analyzed. In vivo and in vitro studies were conducted with fresh human ccRCC tumors and murine tumor cells.

Outcome measurements and statistical analysis

Immune cell numbers and functions were analyzed by flow cytometry. Glutamine and cytokine concentrations were determined. Survival was compared between different subpopulations of patients using Kaplan-Meier and Cox regression analyses.

Results and limitations

We found that in ccRCC, high interleukin (IL)-23 expression was significantly associated with poor survival in both TCGA (overall survival [OS] hazard ratio [HR] = 2.04, cancer-specific survival [CSS] HR = 2.95; all p < 0.001) and Shanghai (OS HR = 2.07, CSS HR = 3.92; all p < 0.001) cohorts. IL-23 blockade prolongs the survival of tumor-bearing mice, promotes T-cell cytotoxicity in in vitro cultures of human ccRCC tumors, and augments the therapeutic benefits of anti-PD-1 antibodies. Mechanistically, glutamine consumption by ccRCC tumor cells results in the local deprivation of extracellular glutamine, which induces IL-23 secretion by tumor-infiltrating macrophages via the activation of hypoxia-inducible factor 1α (HIF1α). IL-23 activates regulatory T-cell proliferation and promotes IL-10 and transforming growth factor β expression, thereby suppressing tumor cell killing by cytotoxic lymphocytes. The positive correlations between glutamine metabolism, IL-23 levels, and Treg responses are confirmed in both TCGA cohort and tumors from Shanghai ccRCC patients. Study limitations include the unclear impacts of glutamine deprivation and IL-23 on other immune cells.

Conclusions

Macrophage-secreted IL-23 enhanced Treg functions in glutamine-addicted tumors; thus, IL-23 is a promising target for immunotherapy in ccRCC.

Patient summary

In this study, we analyzed the immune components in glutamine-addicted clear cell renal cell carcinoma (ccRCC) tumors from two patient cohorts and conducted both in vitro and in vivo studies. We found that ccRCC tumor cell-intrinsic glutamine metabolism orchestrates immune evasion via interleukin (IL)-23, and IL-23–high patients had significantly poorer survival than IL-23–low patients. IL-23 should thus be considered a therapeutic target in ccRCC, either alone or in combination with immune checkpoint inhibitors.  相似文献   
82.
Ferroptosis is an iron-dependent novel cell death pathway. Deferoxamine, a ferroptosis inhibitor, has been reported to promote spinal cord injury repair. It has yet to be clarified whether ferroptosis inhibition represents the mechanism of action of Deferoxamine on spinal cord injury recovery. A rat model of Deferoxamine at thoracic 10 segment was established using a modified Allen's method. Ninety 8-week-old female Wistar rats were used. Rats in the Deferoxamine group were intraperitoneally injected with 100 mg/kg Deferoxamine 30 minutes before injury. Simultaneously, the Sham and Deferoxamine groups served as controls. Drug administration was conducted for 7 consecutive days. The results were as follows:(1) Electron microscopy revealed shrunken mitochondria in the spinal cord injury group.(2) The Basso, Beattie and Bresnahan locomotor rating score showed that recovery of the hindlimb was remarkably better in the Deferoxamine group than in the spinal cord injury group.(3) The iron concentration was lower in the Deferoxamine group than in the spinal cord injury group after injury.(4) Western blot assay revealed that, compared with the spinal cord injury group, GPX4, xCT, and glutathione expression was markedly increased in the Deferoxamine group.(5) Real-time polymerase chain reaction revealed that, compared with the Deferoxamine group, mRNA levels of ferroptosis-related genes Acyl-CoA synthetase family member 2(ACSF2) and iron-responsive element-binding protein 2(IREB2) were up-regulated in the Deferoxamine group.(6) Deferoxamine increased survival of neurons and inhibited gliosis. These findings confirm that Deferoxamine can repair spinal cord injury by inhibiting ferroptosis. Targeting ferroptosis is therefore a promising therapeutic approach for spinal cord injury.  相似文献   
83.
Cerebral ventricular infection(CVI) is one of the most dangerous complications in neurosurgery because of its high mortality and disability rates. Few studies have examined the application of neuroendoscopic surgical techniques(NESTs) to assess and treat CVI. This multicenter, retrospective study was conducted using clinical data of 32 patients with CVI who were assessed and treated by NESTs in China. The patients included 20 men and 12 women with a mean age of 42.97 years. NESTs were used to obliterate intraventricular debris and pus, fenestrate or incise the intraventricular compartment and reconstruct cerebrospinal fluid circulation, and remove artificial material. Intraventricular irrigation with antibiotic saline was applied after neuroendoscopic surgery(NES). Secondary hydrocephalus was treated by endoscopic third ventriculostomy or a ventriculoperitoneal shunt. Neuroendoscopic findings of CVI were used to classify patients into Grade I(n = 3), Grade II(n = 13), Grade III(n = 10), and Grade IV(n = 6) CVI. The three patients with grade I CVI underwent one NES,the 23 patients with grade II/III CVI underwent two NESs, and patients with grade IV CVI underwent two(n = 3) or three(n = 3) NESs.The imaging features and grades of neuroendoscopy results were positively related to the number of neurosurgical endoscopic procedures.Two patients died of multiple organ failure and the other 30 patients fully recovered. Among the 26 patients with secondary hydrocephalus,18 received ventriculoperitoneal shunt and 8 underwent endoscopic third ventriculostomy. There were no recurrences of CVI during the 6-to 76-month follow-up after NES. Application of NESTs is an innovative method to assess and treat CVI, and its neuroendoscopic classification provides an objective, comprehensive assessment of CVI. The study trial was approved by the Institutional Review Board of Beijing Shijitan Hospital, Capital Medical University, China.  相似文献   
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杜华  张宁  闫璞 《天津中医药》2020,37(5):571-574
肾病综合征是儿童和成人常见的肾脏疾病之一,激素治疗常不能达到满意的效果,并会出现多种不良反应。张宁教授运用中医治疗肾病综合征经验丰富,认为肾病综合征病性虚实夹杂,脾肾亏虚为本,肝失疏泄、湿热内阻、瘀血停滞为标。标实的病理因素由本虚引起及加重。治以“固本泻浊法”,健脾益肾,兼以调肝养血、清热化湿、活血化瘀,提高了临床疗效,减少了不良反应。  相似文献   
90.
目的 研究伞骨草水提物的利尿和抗炎作用,以及利尿后对电解质平衡、糖代谢及肾脏功能的影响,并对伞骨草水提物安全性进行初步评价。方法 采用小鼠代谢笼法,检测盐水负荷小鼠在给药6 h后的排尿量,并分析小鼠尿液中离子浓度、血清中糖原、尿素氮和肌酐的变化;采用二甲苯致小鼠耳廓肿胀法,计算耳廓肿胀度及肿胀抑制率,角叉菜胶致大鼠足趾肿胀法,计算足趾肿胀率,小鼠急性毒性试验初步评价伞骨草水提物的安全性。结果 与对照组比较,伞骨草水提物能明显增加小鼠的排尿量,尿液中K+、Cl-的浓度明显增加,高剂量组Na+、Ca2+浓度明显增加;伞骨草对小鼠血清中的糖原、尿素氮和肌酐均无明显影响;伞骨草中、高剂量对二甲苯所致小鼠耳廓肿胀和角叉菜胶所致大鼠足趾肿胀具有明显的抑制作用;伞骨草水提物24 h内小鼠单次灌胃给药急性毒性试验的LD50为:12.33 g·kg-1(相当于生药82.15 g·kg-1),动物在4 h内出现毒性反应,主要表现为主要表现为腹泻、俯卧、竖毛、运动失调、死亡,腹泻至给药第2天恢复。结论 伞骨草水提物具有明显的利尿和抗炎作用,并且对机体的血糖水平和肾脏功能无明显影响。  相似文献   
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