Facile access to bicyclo[2.1.1]hexanes by Lewis acid-catalyzed formal cycloaddition between silyl enol ethers and bicyclo[1.1.0]butanes.

Saturated three-dimensional carbocycles have gained increasing prominence in synthetic and medicinal chemistry. In particular, bicyclo[2.1.1]hexanes (BCHs) have been identified as the molecular replacement for benzenes. Here, we present facile access to a variety of BCHs via a stepwise two-electron formal (3 + 2) cycloaddition between silyl enol ethers and bicyclo[1.1.0]butanes (BCBs) under Lewis acid catalysis. The reaction features wide functional group tolerance for silyl enol ethers, allowing the efficient construction of two vicinal quaternary carbon centers and a silyl-protected tertiary alcohol unit in a streamlined fashion. Interestingly, the reaction with conjugated silyl dienol ethers can provide access to bicyclo[4.1.1]octanes (BCOs) equipped with silyl enol ethers that facilitate further transformation. The utilities of this methodology are demonstrated by the late-stage modification of natural products, transformations of tertiary alcohol units on bicyclo[2.1.1]hexane frameworks, and derivatization of silyl enol ethers on bicyclo[4.1.1]octanes, delivering functionalized bicycles that are traditionally inaccessible.

Identification of COQ2 as a regulator of proliferation and lipid peroxidation through genome-scale CRISPR-Cas9 screening in myeloma cells.

Multiple myeloma (MM) is the second most common malignant haematological disease with a poor prognosis. The limit therapeutic progress has been made in MM patients with cancer relapse, necessitating deeper research into the molecular mechanisms underlying its occurrence and development. A genome-wide CRISPR-Cas9 loss-of-function screening was utilized to identify potential therapeutic targets in our research. We revealed that COQ2 plays a crucial role in regulating MM cell proliferation and lipid peroxidation (LPO). Knockout of COQ2 inhibited cell proliferation, induced cell cycle arrest and reduced tumour growth in vivo. Mechanistically, COQ2 promoted the activation of the MEK/ERK cascade, which in turn stabilized and activated MYC protein. Moreover, we found that COQ2-deficient MM cells increased sensitivity to the LPO activator, RSL3. Using an inhibitor targeting COQ2 by 4-CBA enhanced the sensitivity to RSL3 in primary CD138+ myeloma cells and in a xenograft mouse model. Nevertheless, co-treatment of 4-CBA and RSL3 induced cell death in bortezomib-resistant MM cells. Together, our findings suggest that COQ2 promotes cell proliferation and tumour growth through the activation of the MEK/ERK/MYC axis and targeting COQ2 could enhance the sensitivity to ferroptosis in MM cells, which may be a promising therapeutic strategy for the treatment of MM patients.

Downregulation of RCN1 promotes pyroptosis in acute myeloid leukemia cells.

Reticulocalbin-1 (RCN1) is expressed aberrantly and at a high level in various tumors, including acute myeloid leukemia (AML), yet its impact on AML remains unclear. In this study, we demonstrate that RCN1 knockdown significantly suppresses the viability of bone marrow mononuclear cells (BMMNCs) from AML patients but does not affect the viability of granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood stem cells (PBSCs) from healthy donors in vitro. Downregulation of RCN1 also reduces the viability of AML cell lines. Further studies showed that the RCN1 knockdown upregulates type I interferon (IFN-1) expression and promotes AML cell pyroptosis through caspase-1 and gasdermin D (GSDMD) signaling. Deletion of the mouse Rcn1 gene inhibits the viability of mouse AML cell lines but not the hematopoiesis of mouse bone marrow. In addition, RCN1 downregulation in human AML cells significantly inhibited tumor growth in the NSG mouse xenograft model. Taken together, our results suggest that RCN1 may be a potential target for AML therapy.

Anti-Acute Myeloid Leukemia Activity of CD38-CAR-T Cells with PI3Kδ Downregulation.

We previously constructed a nanobody-based anti-CD38 chimeric antigen receptor T (CD38-CAR-T) cell efficiently against multiple myeloma. As CD38 is also expressed on most tumor cells of acute myeloid leukemia (AML), we wondered about its efficacy in treating AML. In this study, we demonstrated that our CD38-CAR-T cells effectively lysed CD38+ AML cell lines, including NB4, U937, HL-60, THP-1 with an E:T (effector/target cells) ratio of 1:8, and primary AML cells from patients with a low E:T ratio of 1:16. Moreover, recent studies showed that inhibition of PI3Kδ could enhance CAR-T-cell efficacy. We constructed PI3Kδ-downregulated CD38-CAR-T cells with a CD38-CAR lentiviral vector containing short hairpin RNA (shRNA) sequences against PI3Kδ. CD38-CAR-T cells with PI3Kδ downregulation maintained their antileukemia function against both AML cell lines and primary AML cells while reducing the release of IL-2, IFN-γ, and TNF when co-culturing with AML cell lines. Both CD38-CAR-T and PI3Kδ-downregulated CD38-CAR-T-cell therapy significantly improved the survival of AML mice, whereas the latter had an even better effect on survival. In summary, our study demonstrated that CD38-CAR-T cells had promising activity against AML, and PI3Kδ downregulation in CD38-CAR-T cells could reduce some cytokines release without impairing their antileukemia function.

Alternative splicing analysis showed the splicing factor polypyrimidine tract-binding protein 1 as a potential target in acute myeloid leukemia therapy.

Alternative splicing (AS) is a universal post-transcriptional regulation process in cells, and increasing evidences have validated its crucial role in tumors. We collected AS event, gene expression, and clinical data of 178 AML patients from The Cancer Genome Atlas (TCGA) project. More than 1,000 AS events were found associated with overall survival (OS), and alternate promoter (AP) events were the most significant. The expression of the KIAA0930 transcript was the most significantly different AS event selected from AP events and significantly correlated with the expression of the splicing factor (SF) polypyrimidine tract-binding protein 1 (PTBP1). Then, the roles of PTBP1 on AS of the KIAA0930 and the proliferation of AML cells were confirmed. KIAA0930 variant 1 (KIAA0930-1) was upregulated and variant 2 (KIAA0930-2) downregulated with knockdown PTBP1 expression of AML cells by specific shRNA. A low level of PTBP1 can decrease the proliferation ability of AML cells. In conclusion, the results showed that PTBP1 might be a potential target for AML therapy.

Global trends and prospects about inflammasomes in stroke: a bibliometric analysis.

BACKGROUND: Sterile inflammation is a key pathological process in stroke. Inflammasome activation has been implicated in various inflammatory diseases, including ischemic stroke and hemorrhagic stroke. Hence, targeting inflammasomes is a promising approach for the treatment of stroke. METHODS: We applied bibliometric methods and techniques. The Web of Science Core Collection was searched for studies indexed from database inception to November 26, 2020. We generated various visual maps to display publications, authors, sources, countries, and keywords. RESULTS: Our literature search yielded 427 publications related to inflammasomes involved in stroke, most of which consisted of original research articles and reviews. In particular, we found that there was a substantial increase in the number of relevant publications in 2018. Furthermore, most of the publications with the highest citation rates were published in 2014. Relatively, the field about inflammasomes in stroke developed rapidly in 2014 and 2018. Many institutions contributed to these publications, including those from China, the United States, and worldwide. We found that NLR family pyrin domain containing 3 (NLRP3) was the most studied, followed by NLRP1, NLRP2, and NLRC4 among the inflammasomes associated with stroke. Analysis of keywords suggested that the most studied mechanisms involved dysregulation of extracellular pH, efflux of Ca2+ ions, dysfunction of K+/Na+ ATPases, mitochondrial dysfunction, and damage to mitochondrial DNA. CONCLUSIONS: Given the potential diagnostic and therapeutic implications, the specific mechanisms of inflammasomes contributing to stroke warrant further investigation. We used bibliometric methods to objectively present the global trend of inflammasomes in stroke, and to provide important information for relevant researchers.

The effect of Guanxin Shutong capsule on alleviating the myocardial fibrosis in heart failure rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Guanxin Shutong (GXST) capsule is a renowned traditional Chinese medicine widely used for the treatment of cardiovascular diseases in the clinic. However, no pharmacological experimental studies of GXST has been reported on the treatment of pressure overload-induced heart failure. This study aimed to investigate the effects of GXST capsule on ameliorating myocardial fibrosis conditions in pressure overload-induced heart failure rats. MATERIAL AND METHODS: Rats were randomly divided into 6 groups: Normal group, Model group, GXST-treated group at a dose of 0.5 g/kg, 1 g/kg, 2 g/kg, respectively, and digoxin positive control group at a dose of 1 mg/kg. After 4 weeks of administration, cardiac function was evaluated by echocardiography. Cardiac injury and fibrotic conditions were evaluated by H&E staining, Masson staining, and Sirius Red staining. Myocardial fibrosis was evaluated by immunohistochemistry staining and Western blot. RESULTS: GXST significantly inhibited cardiac fibrosis, reduced the excessive deposition of collagen, and finally improved cardiac function. GXST reversed ventricular remodeling might be through the TGF-ß/Smad3 pathway. CONCLUSION: GXST capsule demonstrated a strong anti-fibrosis effect in heart failure rats by inhibiting the TGF-ß/Smad3 signaling pathway.

RNF220 promotes the proliferation of leukaemic cells and reduces the degradation of the Cyclin D1 protein through USP22.

Ring finger proteins contain a characteristic ring finger motif and perform a wide range of biological functions in living organisms. These genes are abnormally expressed in many cancers. We found that the expression level of Ring finger protein 220 (RNF220) was negatively correlated with the disease-free survival (DFS) and overall survival (OS) of acute myeloid leukaemia (AML) patients. Moreover, the mRNA level of this gene is significantly higher in the bone marrow cells of AML patients than in the mobilized peripheral blood haematopoietic stem cells of healthy donors. The overexpression of RNF220 promotes the proliferation of AML cells and accelerates the transition from G1 phase to S phase. Increased protein levels and decreased ubiquitylation levels of Cyclin D1 were observed in the nuclei of cells overexpressing RNF220 compared to those of control cells. The protein level of USP22 was also increased in cells overexpressing RNF220. RNF220 cannot enhance the stability of the Cyclin D1 protein without increased expression of the USP22 protein. Our study provided proof of principle to show that RNF220 promotes stabilization of the Cyclin D1 protein via USP22.

Guanxinshutong capsule ameliorates cardiac function and architecture following myocardial injury by modulating ventricular remodeling in rats.

Guanxinshutong capsule (GXST), which consists of five traditional Chinese medicines, has been used for a long time in China for the treatment of cardiovascular diseases, such as coronary artery disease and myocardial infarction. However, the effects on GXST on myocardial injury (MI) have not been studied in detail. In these experiments, we found that GXST administration decreased MI-associated ventricular remodeling (VR) with a reduction in interventricular septal thickness in diastole (IVSd), left ventricular posterior wall diameter in systole (LVPWs), and left ventricular posterior wall diameter in diastole (LVPWd) to ameliorate cardiac function and architecture, as measured by echocardiography. Furthermore, histological analysis showed that GXST could ameliorate pathological alterations in the myocardium. And Sirius red staining, wheat germ agglutinin staining and inflammation-related immunohistochemistry results showed that GXST ameliorated the fibrosis areas, cardiac hypertrophy and inflammation (IL-6 and TNF-α). In addition, GXST upregulated intercellular junction proteins (N-cad and Cx-43) and downregulated the angiogenesis-related proteins (PDGF and VEGFA), myocardial fibrosis-related proteins (TGF-ß1), and matrix metalloproteinase (MMP-2 and MMP-9). We also found that GXST medium-dose group (1 g/kg/d) dosage was the most efficacious. In conclusion, GXST protected cardiac tissues against MI by reducing VR, thus indicating the potential application of GXST in the treatment of MI.

Gene coexpression network analysis revealed biomarkers correlated with blast cells and survival in acute myeloid leukemia.

Acute myeloid leukemia (AML) is a hematological malignancy with a poorly understood pathogenesis, especially among patients with no known cytogenetic abnormalities. Furthermore, there is a lack of therapeutic gene targets and diagnostic biomarkers for the effective treatment of AML. The present study aimed to identify candidate biomarkers correlated with the clinical prognosis of patients with AML. Leukemic cells from 5 patients with AML exhibiting a normal karyotype, and hematopoietic cells from 5 healthy donors were processed for RNA sequencing (RNA-seq), and the obtained RNA expression profiles were subjected to weighted gene correlation network analysis. A novel group of genes (the red module) were identified to be significantly associated with AML, and this module contained a closely connected network with 147 nodes, which corresponded to 114 mRNAs. Analysis of the correlation between these mRNAs and blast cell percentage, overall survival (OS) and disease-free survival (DFS) using cases from The Cancer Genome Atlas (TCGA) database revealed that CSF3R, ALPL and LMTK2 were negatively associated with the percentage of blast cells, while high expression of these genes was associated with longer OS and DFS in patients with AML. The differential expression of these three genes between patients with AML and healthy control subjects was supported using the Genotype-Tissue Expression and TCGA databases and was further confirmed using reverse transcription-quantitative (RT-qPCR). These genes exhibited significantly lower expression in patients with AML compared with control subjects. The results indicated that CSF3R, ALPL and LMTK2 exhibit the potential to be prognostic biomarkers. However, the biological functions of these three candidate genes need to be assessed in further studies.

CircBA9.3 supports the survival of leukaemic cells by up-regulating c-ABL1 or BCR-ABL1 protein levels.

The unchecked tyrosine kinase activity of BCR-ABL1 contributes to the immortality of leukaemic cells. Therefore, this oncogene is a highly important therapeutic target for chronic myelogenous leukaemia (CML). Tyrosine kinase inhibitors (TKIs) are an excellent drug treatment for CML patients. However, there are still some patients who are not responsive to TKIs. We found that a novel circular RNA (circRNA), named circBA9.3, is derived from BCR-ABL1. CircBA9.3 can efficiently promote the proliferation and inhibit apoptosis of cancer cells. In addition, some patients with TKI resistance have elevated circBA9.3 expression, which is positively correlated with the level of BCR-ABL1. Furthermore, circBA9.3 is predominantly located in the cytoplasm and enhances c-ABL1 and BCR-ABL1 oncoprotein expression. Thus, circBA9.3 is a molecule associated with increased tyrosine kinase activity that promotes resistance against TKI therapy. In this study, we provided a new potential target for the treatment of TKI-resistant CML patients.

Association of plasma intermedin levels with progression and metastasis in men after radical prostatectomy for localized prostatic cancer.

BACKGROUND: Adrenomedullin levels in the peripheral blood are associated with prognosis of some cancers. Intermedin is structural similarities to adrenomedullin. OBJECTIVE: The current study aimed to investigate the prognostic value of plasma intermedin levels for progression and distant metastasis in prostate cancers. METHODS: This study included 218 patients undergoing radical prostatectomy for localized prostatic cancer and 218 age-matched healthy men. Plasma intermedin levels were measured using radioimmunoassay. The relationships between plasma intermedin levels and 5-year progression and 5-year distant metastasis were evaluated using a multivariate analysis. RESULTS: Plasma intermedin levels were markedly higher in all patients than in healthy men. Patients with Gleason score ≥ 7, tumor node metastasis stage T2, organ unconfined, present extra-prostatic extension, seminal vesicle invasion or positive lymph node had higher intermedin levels. Intermedin was identified as a prognostic predictor for 5-year progression and 5-year metastasis. Under receiver operating characteristic curves, intermedin had high predictive values for 5-year progression and 5-year metastasis. CONCLUSIONS: Elevated plasma intermedin levels are independently associated with long-term recurrence and distant metastasis of prostate cancer and intermedin has potential to be a prognostic predictive biomarker for prostate cancer.

[Determination of plasma protein binding rate of methyl protodioscin with ultrafiltration].

OBJECTIVE: To study the plasma protein binding rate of methyl protodioscin. METHOD: The ultrafiltration was employed to determine the plasma protein binding rate of methyl protodioscin. The plasma concentrations of methyl protodioscin were measured by HPLC-MS-MS. RESULT: The plasma protein binding rate of methyl protodioscin with rat plasma at the concentration of 20.0, 100 and 200 microg x mL(-1) were (94.6 +/- 0.16)%, (91.6 +/- 0.35)% and (86.10 +/- 0.60)%, respectively, while the plasma protein binding rate of methyl protodioscin with normal human plasma at the above concentrations were (82.11 +/- 5.12)%, (84.54 +/- 0.32)% and (88.52 +/- 1.02)%, respectively. CONCLUSION: The binding rate of methyl protodioscin with plasma protein is high.