circZBTB44通过调控AKT通路促进肾透明细胞癌增殖和迁移的研究

目的 探究circZBTB44在肾透明细胞癌中的表达情况及探讨circZBTB44在肾透明细胞癌中的生物学功能及促进肾透明细胞癌细胞进展的可能机制。方法 通过qRT-PCR法检测circZBTB44在我院21对肾透明细胞癌组织及细胞系786-O、ACHN中的表达水平;通过放线菌素D实验、RNase R实验、核浆分离实验鉴定circZBTB44的特征;通过siRNA下调circZBTB44的表达后,通过MTS细胞增殖实验、克隆形成实验及Transwell迁移实验来探究circZBTB44对肾透明细胞癌786-O、ACHN的生物学功能影响;通过蛋白免疫印迹实验来探究circZBTB44调控的下游通路。结果 circZBTB44在肾透明细胞癌组织和细胞株786-O和ACHN中明显高表达。下调circZBTB44的表达可明显抑制786-O和ACHN的增殖和迁移能力。下调circZBTB44可抑制肾透明细胞癌786-O和ACHN细胞中AKT的磷酸化。结论 circZBTB44在肾透明细胞癌中高表达。circZBTB44可能通过调控AKT信号通路促进肾透明细胞癌的增殖和迁移。     

PI3K/AKT pathway mediates the antidepressant- and anxiolytic-like roles of hydrogen sulfide in streptozotocin-induced diabetic rats via promoting hippocampal neurogenesis

We have previously demonstrated that hydrogen sulfide (H₂S), the third endogenous gasotransmitter, ameliorates the depression- and anxiety-like behaviors in diabetic rats, but the underlying mechanism remains unclear. The present was aimed to investigate whether the hippocampal phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway mediates H₂S-ameliorated depression- and anxiety-like behaviors in diabetic rats by improving the hippocampal neurogenesis. The depression-like behaviors were examined by Tail suspension test (TST), the anxiety-like behaviors were examined by Elevated plus maze test (EPM), and the locomotor activity was detected by Open Field Test (OFT). The expressions of doublecortin (DCX), neuron-specific nuclear protein (NeuN), glial fibrillary acidic protein (GFAP), p-AKT, and AKT in the hippocampus were determined by Western blot analysis. Results showed that NaHS, a donor of exogenous H₂S, not only activated the hippocampal PI3K/AKT pathway, as evidenced by the increase of phosphorylated AKT, but also favorably reversed streptozotocin (STZ)-disturbed hippocampal neurogenesis, as evidenced by the increases in the expressions of DCX and NeuN as well as the decrease in the expression of GFAP in the hippocampus of STZ-induced diabetic rats. Furthermore, inhibited PI3K/AKT pathway by LY294002 significantly abolished H₂S-exerted the improvement of hippocampal neurogenesis and the antidepressant- and anxiolytic-like effects in the STZ-induced diabetic rats. Taken together, these results uncover that the activation of hippocampal PI3K/AKT pathway plays an important role to restore hippocampal neurogenesis and subsequently to mediate the antidepressant- and anxiolytic-like roles of H₂S in STZ-induced diabetic rats and enhance our understanding of the robustness of H₂S as a therapeutic strategy for treatment of depression in diabetes mellitus.     

Can Next-Generation PI3K Inhibitors Unlock the Full Potential of the Class in Patients With B-Cell Lymphoma?

Although outcomes after first-line therapy for patients with indolent or aggressive non-Hodgkin lymphoma (NHL) are continually improving, relapse is still common. Current treatment options for patients with relapsed or refractory disease have limited efficacy, and various targeted therapies are under investigation to help improve outcomes in this patient population. The phosphatidylinositol 3-kinase (PI3K) pathway was identified as being involved in hematologic malignancies, leading to significant research for potential therapeutic agents. This has led to 3 PI3K inhibitors (idelalisib, copanlisib, and duvelisib) being approved for the treatment of patients with relapsed or refractory follicular lymphoma who have received at least 2 prior systemic therapies, with reported response rates of 40% to 59%. With potential class-specific and PI3K isoform–related toxicities that may limit clinical utility, the safety of the approved PI3K inhibitors has been carefully evaluated to weigh the risk/benefit ratio of therapy. Currently, there are no approved PI3K inhibitors for patients with aggressive NHL. A number of newer PI3K inhibitors are in clinical development for the treatment of relapsed or refractory NHL, aiming to improve treatment benefit for patients. We discuss a number of attributes that are important to increase the therapeutic potential of newer PI3K inhibitors. More promising results may come from combination trials with these newer PI3K inhibitors, developed to limit toxicities (including long-term adverse events), and other antitumor agents.     

Helicobacter pylori induces epithelial-mesenchymal transition in gastric carcinogenesis via the AKT/GSK3β signaling pathway

Helicobacter pylori (H. pylori) is a main risk factor for gastric cancer (GC). Epithelial-mesenchymal transition (EMT) is involved in the development and progression of H. pylori-associated GC. However, the exact molecular mechanism of this process remains unclear. The AKT/GSK3β signaling pathway has been demonstrated to promote EMT in several types of cancer. The present study investigated whether H. pylori infection induced EMT, and promoted the development and metastasis of cancer in the normal gastric mucosa, and whether this process was dependent on AKT activation. The expression levels of the EMT-associated proteins, including E-cadherin and N-cadherin, were determined in 165 gastric mucosal samples of different disease stages by immunohistochemical analysis. The expression levels of E-cadherin, N-cadherin, AKT, phosphorylated (p-)AKT (Ser473), GSK3β and p-GSK3β (Ser9) were further determined in H. pylori-infected Mongolian gerbil gastric tissues and cells co-cultured with H. pylori by immunohistochemical analysis and western blotting. The results indicated that the expression levels of the epithelial marker E-cadherin were decreased, whereas the expression levels of the mesenchymal marker N-cadherin were increased during gastric carcinogenesis. Their expression levels were associated with H. pylori infection. Furthermore, H. pylori infection resulted in downregulation of E-cadherin expression and upregulation of N-cadherin expression in Mongolian gerbils and GES-1 cells. In addition, an investigation of the associated mechanism of action revealed that p-AKT (Ser473) and p-GSK3β (Ser9) were activated in GES-1 cells following co-culture with H. pylori. Furthermore, following pretreatment of the cells with the AKT inhibitor VIII, the expression levels of E-cadherin, N-cadherin, p-AKT and p-GSK3β did not show significant differences between GES-1 cells that were co-cultured with or without H. pylori. The levels of p-AKT and p-GSK3β were increased in H. pylori-infected Mongolian gerbils. In conclusion, the present study demonstrated that H. pylori infection activated AKT and resulted in the phosphorylation and inactivation of GSK3β, which in turn promoted early stage EMT. These effects were AKT-dependent. This mechanism may serve as a prerequisite for GC development.     

铜绿假单胞菌注射液对肺癌A549细胞自噬及PI3K/Akt通路的影响

目的探究铜绿假单胞菌注射液(PA-MSHA)对肺癌A549细胞自噬及磷脂酰肌醇-3激酶(PI3K)/蛋白激酶B(Akt)通路的影响。方法体外培养人肺癌A549细胞,随机分为空白对照组、LY294002组(加入20μmol/L LY294002),PA-MSHA干预组(加入0.5×10^9/mL、1.0×10^9/mL、2.0×10^9/mL PA-MSHA)。干预培养48 h后,MTT法检测各组细胞活性,平板克隆形成实验检测各组细胞增殖能力,透射电子显微镜观察各组细胞自噬情况,Western blot检测各组细胞中自噬相关蛋白p62、LC3Ⅰ、LC3Ⅱ及PI3K/Akt通路相关蛋白PI3K、Akt、p-PI3K、p-Akt表达。结果与空白对照组相比,LY294002组、0.5×10^9/mL、1.0×10^9/mL、2.0×10^9/mL PA-MSHA组细胞增殖抑制率、LC3Ⅱ/LC3Ⅰ蛋白表达显著升高(P<0.05),自噬体个数增加,细胞克隆形成率、p62、p-PI3K/PI3K、p-Akt/Akt蛋白表达显著降低(P<0.05);与LY294002组相比,0.5×10^9/mL、1.0×10^9/mL PA-MSHA组细胞增殖抑制率、LC3Ⅱ/LC3Ⅰ蛋白表达显著降低(P<0.05),自噬体个数减少,细胞克隆形成率、p62、p-PI3K/PI3K、p-Akt/Akt蛋白表达显著升高(P<0.05);与0.5×10^9/mL、1.0×10^9/mL PA-MSHA组相比,2.0×10^9/mL PA-MSHA组细胞增殖抑制率、LC3Ⅱ/LC3Ⅰ蛋白表达显著升高(P<0.05),自噬体个数增加,细胞克隆形成率、p62、p-PI3K/PI3K、p-Akt/Akt蛋白表达显著降低(P<0.05)。结论PA-MSHA可能通过调控PI3K/Akt信号通路,促进肺癌A549细胞自噬,抑制细胞增殖。     

Fatal unexpected death due to X-linked lymphoproliferative disease

X-linked lymphoproliferative disease (XLP) is a rare immunodeficiency disease characterized by severe immune disorder and extreme vulnerability to Epstein-Barr virus (EBV) infections. Here we report a 14-month-old Chinese boy presenting with fulminant infectious mononucleosis (FIM) following EBV infection, and died of hepatic failure within one week of disease progression. Postmortem examination revealed icterus, ascites, extensive enlarged mesenteric lymph nodes and hepatosplenomegaly. Histopathological examination showed diffuse proliferation of cytotoxic T lymphoid cells and hemophagocytosis in multiple organs. The family history revealed his brother had died under similar circumstances at 5 five years of age. The cause of death of the boy was ascribed to XLP. To the best of our knowledge, there is few autopsy-confirmed XLP case in the forensic practice. The complicated manifestations and systemic pathological changes should be well recognized by clinicians and forensic pathologists.     

Radiation-Related Deregulation of TUBB3 and BRCA1/2 and Risk of Secondary Lung Cancer in Women With Breast Cancer

IntroductionBreast cancer survivors are at increased risk of developing unrelated primary cancers, particularly lung cancer. Evidence indicates that sex hormones as well as a deregulation of DNA-repair pathways may contribute to lung cancer onset. We investigated whether the hormone status and expression of markers involved in DNA repair (BRCA1/2, ERCC1, and P53R2), synthesis (TS and RRM1), and cell division (TUBB3) might be linked to lung cancer risk.Patients and MethodsThirty-seven breast cancer survivors with unrelated lung cancer and 84 control subjects comprising women with breast cancer (42/84) or lung cancer (42/84) were enrolled. Immunohistochemistry on tumor tissue was performed. Geometric mean ratio was used to assess the association of marker levels with patient groups.ResultsEstrogen receptor was expressed in approximately 90% of the breast cancer group but was negative in the majority of the lung cancer group, a result similar to the lung cancer control group. Likewise, ER isoform β was weakly expressed in the lung cancer group. Protein analysis of breast cancer versus control had a significantly lower expression of BRCA1, P53R2, and TUBB3. Likewise, a BRCA1 reduction was observed in the lung cancer group concomitant with a BRCA2 increase. Furthermore, BRCA2 and TUBB3 increased in ipsilateral lung cancer in women who had previously received radiotherapy for breast cancer.ConclusionThe decrease of DNA-repair proteins in breast cancer could make these women more susceptible to therapy-related cancer. The increase of BRCA2 and TUBB3 in lung cancer from patients who previously received radiotherapy for breast cancer might reflect a tissue response to exposure to ionizing radiation.     

Interacting with α7 nAChR is a new mechanism for AChE to enhance the inflammatory response in macrophages

Acetylcholine (ACh) regulates inflammation via α7 nicotinic acetylcholine receptor (α7 nAChR). Acetylcholinesterase (AChE), an enzyme hydrolyzing ACh, is expressed in immune cells suggesting non-classical function in inflammatory responses. Here, the expression of PRiMA-linked G4 AChE was identified on the surface of macrophages. In lipopolysaccharide-induced inflammatory processes, AChE was upregulated by the binding of NF-κB onto the ACHE promotor. Conversely, the overexpression of G4 AChE inhibited ACh-suppressed cytokine release and cell migration, which was in contrast to that of applied AChE inhibitors. AChEmt, a DNA construct without enzymatic activity, was adopted to identify the protein role of AChE in immune system. Overexpression of G4 AChEmt induced cell migration and inhibited ACh-suppressed cell migration. The co-localization of α7 nAChR and AChE was found in macrophages, suggesting the potential interaction of α7 nAChR and AChE. Besides, immunoprecipitation showed a close association of α7 nAChR and AChE protein in cell membrane. Hence, the novel function of AChE in macrophage by interacting with α7 nAChR was determined. Together with hydrolysis of ACh, AChE plays a direct role in the regulation of inflammatory response. As such, AChE could serve as a novel target to treat age-related diseases by anti-inflammatory responses.