The acute myeloid leukemia (AML) patients obtain limited benefits from current immune checkpoint blockades (ICBs), although immunotherapy have achieved encouraging success in numerous cancers. Here, ...we found that V-domain Ig suppressor of T cell activation (VISTA), a novel immune checkpoint, is highly expressed in primary AML cells and associated with poor prognosis of AML patients. Targeting VISTA by anti-VISTA mAb boosts T cell-mediated cytotoxicity to AML cells. Interestingly, high expression of VISTA is positively associated with hyperactive STAT3 in AML. Further evidence showed that STAT3 functions as a transcriptional regulator to modulate VISTA expression by directly binding to DNA response element of VISTA gene. We further develop a potent and selective STAT3 inhibitor W1046, which significantly suppresses AML proliferation and survival. W1046 remarkably enhances the efficacy of VISTA mAb by activating T cells via inhibition of STAT3 signaling and down-regulation of VISTA. Moreover, combination of W1046 and VISTA mAb achieves a significant anti-AML effect in vitro and in vivo. Overall, our findings confirm that VISTA is a potential target for AML therapy which transcriptionally regulated by STAT3 and provide a promising therapeutic strategy for immunotherapy of AML.
Chemoresistance, the major obstacle in breast cancer chemotherapy, results in unnecessary chemotherapy and wasting of medical resources. No feasible method has been available to predict ...chemoresistance before chemotherapy. In our previous study, elevated expression of transient receptor potential channel TRPC5 was found to be an essential element for chemoresistance in breast cancer cells, and it was determined that it could be transferred to chemosensitive breast cancer cells through releasing extracellular vesicles (EV) containing TRPC5 from chemoresistant cells, resulting in acquired chemoresistance. Exosomes, a type of EV, are secreted membrane‐enclosed vesicles of 50–150‐nm diameter. In this study we found that circulating exosomes in peripheral blood from breast cancer patients carried TRPC5. In the present study, circulating exosome‐carrying TRPC5 (cirExo‐TRPC5) level was significantly correlated with TRPC5 expression level in breast cancer tissues and tumor response to chemotherapy. Furthermore, increased cirExo‐TRPC5 level after chemotherapy preceded progressive disease (PD) based on imaging examination and strongly predicted acquired chemoresistance. Taken together, our study demonstrated that cirExo‐TRPC5 might act as a noninvasive chemoresistance marker and might serve as an adjuvant to the current imaging examination‐based chemoresistance.
Increased cirExo‐TRPC5 level after chemotherapy was preceding progressive disease (PD) based on imaging examination and strongly predicted acquired chemoresistance. CrExo‐TRPC5 might act as a noninvasive chemoresistance marker and might serve as an adjuvant to the current imaging examination‐based chemoresistance.
Glioblastoma (GBM) are the most malignant brain tumors in humans and have a very poor prognosis. Temozolomide (TMZ), the only chemotherapeutic drug for GBM treatment, induced apoptosis but frequently ...developed resistance. Non-apoptotic cell death offers an alternative strategy to fight cancers. Our previous studies showed that 2-methoxy-6-acetyl-7-methyljuglone (MAM), a natural product, induced necroptosis in lung and colon cancer cells. The current study is designed to investigate its therapeutic potentials for GBM with in vitro and in vivo models. The protein expression of NAD(P)H: quinone oxidoreductase 1 (NQO1) in human GBM specimens were detected by immunohistochemistry. Effect of MAM on NQO1 was measured by recombinant protein and cellular thermal shift assay. The roles of NQO1 activation, superoxide (O2−) generation, calcium (Ca2+) accumulation, and c-Jun N-terminal kinase (JNK1/2) activation in MAM-induced cell death in U87 and U251 glioma cells were investigated. The effect of MAM on tumor growth was tested with a U251 tumor xenograft zebrafish model. Results showed that the NQO1 expression is positively correlated with the degree of malignancy in GBM tissues. MAM could directly bind and activate NQO1. Furthermore, MAM treatment induced rapid O2− generation, cytosolic Ca2+ accumulation, and sustained JNK1/2 activation. In addition, MAM significantly suppressed tumor growth in the zebrafish model. In conclusion, MAM induced GBM cell death by triggering an O2−/Ca2+/JNK1/2 dependent programmed necrosis. NQO1 might be the potential target for MAM and mediated its anticancer effect. This non-apoptotic necrosis might have therapeutic potentials for GBM treatment.
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•MAM induced non-apoptotic programmed necrosis in human GBM cells by targeting NQO1.•MAM-induced NQO1-dependent necrosis is mediated by superoxide generation, calcium accumulation, and JNK1/2 activation.•MAM shows anticancer effect in xenograft zebrafish model possibly mediated by induction of programmed necrosis.
The activation of hepatic stellate cells (HSCs) plays a critical role in liver fibrosis. In the current study, γ-mangostin (γ-man), one of the major xanthones from mangosteen (Garcinia mangostana), ...was found to alleviate fibrogenesis in human immortalized HSCs (LX-2 cells) and in liver from chronic carbon tetrachloride (CCl4) injured mice. γ-Man suppressed the expression levels of collagen I and α-smooth muscle actin (α-SMA) in LX-2 cells in both dose and time dependent manners. Furthermore, γ-man inhibited NAD(P)H oxidase activity through induction of sirtuin 3 (SIRT3), resulting in reduced intracellular oxidative stress in LX-2 cells. Moreover, γ-man stimulated the expression of histone deacetylase 1, which in turn decreased the acetylation and cytoplasmic shuttling of high mobility group box 1 (HMGB1), to impair autocrine HMGB1-induced HSC activation. In CCl4-injured mice, γ-man enhanced the expression of SIRT3 and decreased the expression of HMGB1, resulting in decreased accumulation of collagen I and α-SMA in liver. Consequently, γ-man might be a potent candidate to treat oxidative stress induced liver fibrosis.
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•γ-Mangostin alleviates fibrogenesis in vitro and in vivo.•γ-Mangostin enhances the expression and activity of SIRT3.•γ-Mangostin suppresses NOX activity and decreases intracellular oxidative stress.•γ-Mangostin decreases the activity of HDAC1 and the acetylation level of HMGB1.
A multiphysics simulation technique based on the finite element method is developed for the reliability analysis of interconnects. The multiphysics simulation characterizes multidisciplinary, ...including electrical, thermal, and mechanical, aspects of interconnects. It is well known that the major bottleneck preventing 3-D simulations from gaining further popularity is the computational efficiency in dealing with practically large-scale problems. To address this problem, the proposed multiphysics simulation is devised for analyzing large-scale problems with a significantly improved computational efficiency through utilizing a domain decomposition scheme called the finite element tearing and interconnecting, parallel computing, and the localized nature of thermal stresses in the interconnect structures. Both the capability and efficiency of the multiphysics simulation are demonstrated through analyzing large-scale interconnect structures including arrays of solder bumps and bonding wires. Detailed temperature distributions and localized stresses of large amplitude are obtained through the proposed simulation in a highly efficient manner.
Glioblastoma (GBM) is one of the most prevalent malignant primary tumors in the human brain. Temozolomide (TMZ), the chemotherapeutic drug for GBM treatment, induces apoptosis. Unfortunately, ...apoptosis-resistance to TMZ results in treatment failure. GBM shows enhanced expression of NAD(P)H: quinone oxidoreductase 1 (NQO1). Recently, noptosis, a type of NQO1-dependent necrosis, was proposed. Here, we identified that tanshindiol B (TSB) inhibits GBM growth by induction of noptosis. TSB triggered significant cell death, which did not fit the criteria of apoptosis but oxidative stress-induced necrosis. Molecular docking, cellular thermal shift assay, and NQO1 activity assay revealed that TSB bind to and promptly activated NQO1 enzyme activity. As the substrate of NQO1, TSB induced oxidative stress, which resulted in dramatic DNA damage, poly (ADP-ribose) polymerase 1 (PARP1) hyperactivation, and NAD+ depletion, leading to necrotic cell death. These effects of TSB were completely abolished by specific NQO1 inhibitor dicoumarol (DIC). Furthermore, the c-Jun N-terminal kinase 1/2 (JNK1/2) plays an essential role in mediating TSB-induced cell death. Besides, TSB significantly suppressed tumor growth in a zebrafish xenograft model mediated by NQO1. In conclusion, these results showed that TSB was an NQO1 substrate and triggered noptosis of GBM. TSB exhibited anti-tumor potentials in GBM both in vitro and in vivo. This study provides a novel strategy for fighting GBM through the induction of noptosis.
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•Tanshindiol B directly binds to NQO1 and promptly activated NQO1 enzyme activity.•Tanshindiol B induces noptosis, a type of NQO1-dependent necrosis.•Tanshindiol B induces NQO1-dependent DNA damage and PARP1 hyperactivation.•Tanshindiol B suppresses tumor growth in a zebrafish xenograft model.
Combination therapy has been developed as a promising therapeutic approach for hepatocellular carcinoma therapy. Here we report a low toxicity and high performance nanoparticle system that was ...self-assembled from a poly(ethylenimine)–glycyrrhetinic acid (PEI–GA) amphiphilic copolymer as a versatile gene/drug dual delivery nanoplatform. PEI–GA was synthesized by chemical conjugation of hydrophobic GA moieties to the hydrophilic PEI backbone via an acylation reaction. The PEI–GA nanocarrier could encapsulate doxorubicin (DOX) efficiently with loading level about 12% and further condense DNA to form PEI–GA/DOX/DNA complexes to codeliver drug and gene. The diameter of the complexes is 102 ± 19 nm with zeta potential of 19.6 ± 0.2 mV. Furthermore, the complexes possess liver cancer targeting ability and could promote liver cancer HepG2 cell internalization. Apoptosis of cells could be induced by chemotherapy of DOX, and PI3K/Akt/mTOR signaling pathway acts a beneficial effect on the modulation of autophagy. Here, it is revealed that utilizing PEI–GA/DOX/shAkt1 complexes results in effective autophagy and apoptosis, which are useful to cause cell death. The induction of superfluous autophagy is reported to induce type-II cell death and also could increase the sensity of chemotherapy to tumor cells. In this case, combining autophagy and apoptosis is meaningful for oncotherapy. In this study, PEI–GA/DOX/shAkt1 has demonstrated favorable tumor target ability, little side effects, and ideal antitumor efficacy.
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Recent discoveries revealed several types of programmed necrosis, such as necroptosis, ferroptosis, pyroptosis, etc. Necroptosis is mediated by signaling complexes with ...receptor-interacting protein kinases (RIPs) and mixed lineage kinase domain-like protein (MLKL). Here, we described an MLKL mediated non-canonical necroptosis through reactive oxygen species (ROS) in lung cancer cells triggered by a natural compound, tanshinol A (TSA). Morphologically, TSA-induced necrotic cell death is characterized by increased cell volume, transparent of cytoplasm, and rupture of the cell membrane. Biochemically, it induces intracellular ATP depletion and PI penetration. Molecularly, TSA-induced cell death is mediated by MLKL but independent of RIP1 and RIP3. Furthermore, TSA induces MLKL phosphorylation and membrane translocation, and cytosolic calcium accumulation. However, calcium shows no effect on TSA-induced cell death. Especially, TSA induces intracellular ROS generation, which was found to be the upstream of MLKL. Collectively, our data indicated that TSA triggers a novel type of programmed necrosis mediated by MLKL in lung cancer cells, which might have therapeutic potentials for lung cancer treatment.
Aberrant activation of the RAS superfamily is one of the critical factors in carcinogenesis. Among them, KRAS is the most frequently mutated one which has inspired extensive studies for developing ...approaches to intervention. Although the cognition toward KRAS remains far from complete, mounting evidence suggests that a variety of post-translational modifications regulate its activation and localization. In this review, we summarize the regulatory mode of post-translational modifications on KRAS including prenylation, post-prenylation, palmitoylation, ubiquitination, phosphorylation, SUMOylation, acetylation, nitrosylation, etc. We also highlight the recent studies targeting these modifications having exhibited potent anti-tumor activities.
The JAK2/STAT3 signaling pathway plays a critical role in tumorigenesis, and has been suggested as a potential molecular target for anti-melanoma therapeutics. However, few JAK2 inhibitors were being ...tested for melanoma therapy. In this study, eight amentoflavone analogues were evaluated for their activity against human malignant melanoma cells. The most potent analogue, compound 1, inhibited the phosphorylation of JAK2 and STAT3 in human melanoma cells, but had no discernible effect on total JAK2 and STAT3 levels. A cellular thermal shift assay was performed to identify that JAK2 is engaged by 1 in cell lysates. Moreover, compound 1 showed higher antiproliferative activity against human melanoma A375 cells compared to a panel of cancer and normal cell lines. Compound 1 also activated caspase-3 and cleaved PARP, which are markers of apoptosis, and suppressed the anti-apoptotic Bcl-2 level. Finally, compound 1 induced apoptosis in 80% of treated melanoma cells. To our knowledge, compound 1 is the first amentoflavone-based JAK2 inhibitor to be investigated for use as an anti-melanoma agent.
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