技术资料

Severe acute respiratory syndrome virus 2 (SARS-CoV-2) is the cause of the current coronavirus disease 19 (COVID-19) pandemic. Protease inhibitors are under consideration as virus entry inhibitors that prevent the cleavage of the coronavirus spike (S) protein by cellular proteases. Herein,we showed that the protease inhibitor aprotinin (but not the protease inhibitor SERPINA1/alpha-1 antitrypsin) inhibited SARS-CoV-2 replication in therapeutically achievable concentrations. An analysis of proteomics and translatome data indicated that SARS-CoV-2 replication is associated with a downregulation of host cell protease inhibitors. Hence,aprotinin may compensate for downregulated host cell proteases during later virus replication cycles. Aprotinin displayed anti-SARS-CoV-2 activity in different cell types (Caco2,Calu-3,and primary bronchial epithelial cell air-liquid interface cultures) and against four virus isolates. In conclusion,therapeutic aprotinin concentrations exert anti-SARS-CoV-2 activity. An approved aprotinin aerosol may have potential for the early local control of SARS-CoV-2 replication and the prevention of COVID-19 progression to a severe,systemic disease. View Publication

Adenomyosis is also called internal endometriosis and affects about 20{\%} of reproductive-aged women. It seriously reduces life quality of patients because current drug therapies face with numerous challenges. Long-term clinical application of mifepristone exhibits wonderful therapeutic effects with mild side-effects in many disorders since 1982. Since adenomyosis is a refractory disease,we investigate whether mifepristone can be applied in the treatment of adenomyosis. In this study,we investigated the direct effects of mifepristone on human primary eutopic endometrial epithelial cells and stromal cells in adenomyosis. We found that mifepristone causes cell cycle arrest through inhibiting CDK1 and CDK2 expressions and induces cell apoptosis via the mitochondria-dependent signalling pathway in endometrial epithelial cells and stromal cells of adenomyosis. Furthermore,mifepristone inhibits the migration of endometrial epithelial cells and stromal cells through decreasing CXCR4 expression and restricts the invasion of endometrial epithelial cells via suppression of epithelial-mesenchymal transition in adenomyosis. We also found that mifepristone treatment decreases the uterine volume,CA125 concentration and increases the haemoglobin concentration in serum for adenomyosis patients. Therefore,we demonstrate that mifepristone could serve as a novel therapeutic drug in the treatment of adenomyosis,and therefore,the old dog can do a new trick. View Publication

The mechanism of Fas antigen-mediated apoptosis is at present unclear. We show here that the 100,000 x g supernatant from cell lysates prepared from anti-Fas-stimulated JUR-KAT T cells,induces chromatin fragmentation in isolated nuclei with concomitant morphological changes typically seen in apoptosis. The formation of this apoptotic nuclei promoting activity (ANPA) in JURKAT T cells after Fas antigen ligation was blocked by the serine protease inhibitors,TPCK and DCI,and by the interleukin 1-beta-converting enzyme inhibitor,VAD-FMK. In addition,chromatin degradation and morphological changes mediated by the ANPA in isolated nuclei were inhibited by TPCK,but not by DCI or VAD-FMK. These results suggest that Fas-mediated apoptosis in T cells involves the activation of a cascade of proteases. View Publication

Although arsenic trioxide (As(2)O(3)) is an effective therapy in acute promyelocytic leukemia (APL),its use in other malignancies is limited by the toxicity of concentrations required to induce apoptosis in non-APL tumor cells. We looked for agents that would synergize with As(2)O(3) to induce apoptosis in malignant cells,but not in normal cells. We found that trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid),a widely known antioxidant,enhances As(2)O(3)-mediated apoptosis in APL,myeloma,and breast cancer cells. Treatment with As(2)O(3) and trolox increased intracellular oxidative stress,as evidenced by heme oxygenase-1 (HO-1) protein levels,c-Jun terminal kinase (JNK) activation,and protein and lipid oxidation. The synergistic effects of trolox may be specific to As(2)O(3),as trolox does not add to toxicity induced by other chemotherapeutic drugs. We explored the mechanism of this synergy using electron paramagnetic resonance and observed the formation of trolox radicals when trolox was combined with As(2)O(3),but not with doxorubicin. Importantly,trolox protected nonmalignant cells from As(2)O(3)-mediated cytotoxicity. Our data provide the first evidence that trolox may extend the therapeutic spectrum of As(2)O(3). Furthermore,the combination of As(2)O(3) and trolox shows potential specificity for tumor cells,suggesting it may not increase the toxicity associated with As(2)O(3) monotherapy in vivo. View Publication

Autophagy is a cellular response to adverse environment and stress,but its significance in cell survival is not always clear. Here we show that autophagy could be induced in the mammalian cells by chemicals,such as A23187,tunicamycin,thapsigargin,and brefeldin A,that cause endoplasmic reticulum stress. Endoplasmic reticulum stress-induced autophagy is important for clearing polyubiquitinated protein aggregates and for reducing cellular vacuolization in HCT116 colon cancer cells and DU145 prostate cancer cells,thus mitigating endoplasmic reticulum stress and protecting against cell death. In contrast,autophagy induced by the same chemicals does not confer protection in a normal human colon cell line and in the non-transformed murine embryonic fibroblasts but rather contributes to cell death. Thus the impact of autophagy on cell survival during endoplasmic reticulum stress is likely contingent on the status of cells,which could be explored for tumor-specific therapy. View Publication

Many tumors become addicted to autophagy for survival,suggesting inhibition of autophagy as a potential broadly applicable cancer therapy. ULK1/Atg1 is the only serine/threonine kinase in the core autophagy pathway and thus represents an excellent drug target. Despite recent advances in the understanding of ULK1 activation by nutrient deprivation,how ULK1 promotes autophagy remains poorly understood. Here,we screened degenerate peptide libraries to deduce the optimal ULK1 substrate motif and discovered 15 phosphorylation sites in core autophagy proteins that were verified as in vivo ULK1 targets. We utilized these ULK1 substrates to perform a cell-based screen to identify and characterize a potent ULK1 small molecule inhibitor. The compound SBI-0206965 is a highly selective ULK1 kinase inhibitor in vitro and suppressed ULK1-mediated phosphorylation events in cells,regulating autophagy and cell survival. SBI-0206965 greatly synergized with mechanistic target of rapamycin (mTOR) inhibitors to kill tumor cells,providing a strong rationale for their combined use in the clinic. View Publication

Targeting proteins within the N-type voltage-gated calcium channel (CaV2.2) complex has proven to be an effective strategy for developing novel pain therapeutics. We describe a novel peptide aptamer derived from the collapsin response mediator protein 2 (CRMP2),a CaV2.2-regulatory protein. Addition of a 14-carbon myristate group to the peptide (myr-tat-CBD3) tethered it to the membrane of primary sensory neurons near surface CaV2.2. Pull-down studies demonstrated that myr-tat-CBD3 peptide interfered with the CRMP2-CaV2.2 interaction. Quantitative confocal immunofluorescence revealed a pronounced reduction of CaV2.2 trafficking after myr-tat-CBD3 treatment and increased efficiency in disrupting CRMP2-CaV2.2 colocalization compared with peptide tat-CBD3. Consequently,myr-tat-CBD3 inhibited depolarization-induced calcium influx in sensory neurons. Voltage clamp electrophysiology experiments revealed a reduction of Ca,but not Na,currents in sensory neurons after myr-tat-CBD3 exposure. Current clamp electrophysiology experiments demonstrated a reduction in excitability of small-diameter dorsal root ganglion neurons after exposure to myr-tat-CBD3. Myr-tat-CBD3 was effective in significantly attenuating carrageenan-induced thermal hypersensitivity and reversing thermal hypersensitivity induced by a surgical incision of the plantar surface of the rat hind paw,a model of postoperative pain. These effects are compared with those of tat-CBD3-the nonmyristoylated tat-conjugated CRMP2 peptide as well as scrambled versions of CBD3 and CBD3-lacking control peptides. Our results demonstrate that the myristoyl tag enhances intracellular delivery and local concentration of the CRMP2 peptide aptamer near membrane-delimited calcium channels resulting in pronounced interference with the calcium channel complex,superior suppression of calcium influx,and better antinociceptive potential. View Publication

Olive oil intake has been shown to induce significant levels of apoptosis in various cancer cells. These anti-cancer properties are thought to be mediated by phenolic compounds present in olive. These beneficial health effects of olive have been attributed,at least in part,to the presence of oleuropein and hydroxytyrosol. In this study,oleuropein and hydroxytyrosol,major phenolic compound of olive oil,was studied for its effects on growth in MCF-7 human breast cancer cells using assays for proliferation (MTT assay),cell viability (Guava ViaCount assay),cell apoptosis,cellcycle (flow cytometry). Oleuropein or hydroxytyrosol decreased cell viability,inhibited cell proliferation,and induced cell apoptosis in MCF-7 cells. Result of MTT assay showed that 200 mug/mL of oleuropein or 50 mug/mL of hydroxytyrosol remarkably reduced cell viability of MCF-7 cells. Oleuropein or hydroxytyrosol decrease of the number of MCF-7 cells by inhibiting the rate of cell proliferation and inducing cell apoptosis. Also hydroxytyrosol and oleuropein exhibited statistically significant block of G(1) to S phase transition manifested by the increase of cell number in G(0)/G(1) phase. View Publication

Collective invasion can be led by breast cancer cells expressing basal epithelial markers,typified by keratin-14 (KRT14). We analyzed gene expression data from The Cancer Genome Atlas and demonstrated a significant correlation between a KRT14+ invasion signature and a stromal-mediated extracellular matrix (ECM) organization module. We then developed a novel coculture model of tumor organoids with autologous stromal cells. Coculture significantly increased KRT14 expression and invasion of organoids from both luminal and basal murine breast cancer models. However,stromal cell conditioned medium induced invasion but not KRT14 expression. Cancer cells released TGF$\beta$ and that signaling pathway was required for stromal cell-induced invasion and KRT14 expression. Mechanistically,TGF$\beta$ induced NOX4 expression in stromal cells and NOX4 inhibition reduced invasion and KRT14 expression. In summary,we developed a novel coculture model and revealed dynamic molecular interactions between stromal cells and cancer cells that regulate both basal gene expression and invasive behavior. IMPLICATIONS: Fibroblasts within mammary tumors can regulate the molecular phenotype and invasive behavior of breast cancer cells. VISUAL OVERVIEW: http://mcr.aacrjournals.org/content/molcanres/18/11/1615/F1.large.jpg. View Publication

Accumulating evidence suggests important roles for the receptor tyrosine kinase Axl in cancer progression,invasion,metastasis,drug resistance,and patient mortality,highlighting Axl as an attractive target for therapeutic development. We have generated and characterized a potent and selective small-molecule inhibitor,R428,that blocks the catalytic and procancerous activities of Axl. R428 inhibits Axl with low nanomolar activity and blocked Axl-dependent events,including Akt phosphorylation,breast cancer cell invasion,and proinflammatory cytokine production. Pharmacologic investigations revealed favorable exposure after oral administration such that R428-treated tumors displayed a dose-dependent reduction in expression of the cytokine granulocyte macrophage colony-stimulating factor and the epithelial-mesenchymal transition transcriptional regulator Snail. In support of an earlier study,R428 inhibited angiogenesis in corneal micropocket and tumor models. R428 administration reduced metastatic burden and extended survival in MDA-MB-231 intracardiac and 4T1 orthotopic (median survival,{\textgreater}80 days compared with 52 days; P {\textless} 0.05) mouse models of breast cancer metastasis. Additionally,R428 synergized with cisplatin to enhance suppression of liver micrometastasis. Our results show that Axl signaling regulates breast cancer metastasis at multiple levels in tumor cells and tumor stromal cells and that selective Axl blockade confers therapeutic value in prolonging survival of animals bearing metastatic tumors. View Publication

Older organs represent an untapped potential to close the gap between demand and supply in organ transplantation but are associated with age-specific responses to injury and increased immunogenicity,thereby aggravating transplant outcomes. Here we show that cell-free mitochondrial DNA (cf-mt-DNA) released by senescent cells accumulates with aging and augments immunogenicity. Ischemia reperfusion injury induces a systemic increase of cf-mt-DNA that promotes dendritic cell-mediated,age-specific inflammatory responses. Comparable events are observed clinically,with the levels of cf-mt-DNA elevated in older deceased organ donors,and with the isolated cf-mt-DNA capable of activating human dendritic cells. In experimental models,treatment of old donor animals with senolytics clear senescent cells and diminish cf-mt-DNA release,thereby dampening age-specific immune responses and prolonging the survival of old cardiac allografts comparable to young donor organs. Collectively,we identify accumulating cf-mt-DNA as a key factor in inflamm-aging and present senolytics as a potential approach to improve transplant outcomes and availability. View Publication

BACKGROUND The conducting airway epithelium is repaired by tissue specific stem cells (TSC). In response to mild/moderate injury,each TSC repairs a discrete area of the epithelium. In contrast,severe epithelial injury stimulates TSC migration and expands the stem cell's reparative domain. Lung transplantation (LTx) can cause a moderate/severe airway injury and the remodeled airway contains a chimeric mixture of donor and recipient cells. These studies supported the hypothesis,LTx stimulates TSC migration resulting in epithelial chimerism. We tested this hypothesis in cystic fibrosis (CF) LTx patients. METHODS Airway mucosal injury was quantified using bronchoscopic imaging and a novel grading system. Bronchial brushing was used to recover TSC from 10 sites in the recipient and allograft airways. TSC chimerism was quantified by short tandem repeat analysis. TSC self-renewal and differentiation potential were assayed using the clone forming cell frequency and air-liquid-interface methods. Electrophysiology was used to determine if TSC chimerism altered epithelial ion channel activity. RESULTS LTx caused a mild to moderate airway mucosal injury. Donor and recipient TSC were identified in 91{\%} of anastomotic sites and 93{\%} of bronchial airways. TSC chimerism did not alter stem cell self-renewal or differentiation potential. The frequency of recipient TSC was proportional to CF Transmembrane Conductance Regulator (CFTR)-dependent ion channel activity and 33{\%} of allograft regions were at risk for abnormal CFTR activity. CONCLUSIONS LTx in CF patients stimulates bidirectional TSC migration across the anastomoses. TSC chimerism may alter ion homeostasis and compromise the host defense capability of the allograft airway epithelium. View Publication