Friend leukemia virus integration 1 (FLI1), an ETS transcription factor family member, acts as an oncogenic driver in hematological malignancies and promotes tumor growth in solid tumors. However, ...little is known about the mechanisms underlying the activation of this proto-oncogene in tumors.
Immunohistochemical staining showed that FLI1 is aberrantly overexpressed in advanced stage and metastatic breast cancers. Using a CRISPR Cas9-guided immunoprecipitation assay, we identify a circular RNA in the FLI1 promoter chromatin complex, consisting of FLI1 exons 4-2-3, referred to as FECR1.Overexpression of FECR1 enhances invasiveness of MDA-MB231 breast cancer cells. Notably, FECR1 utilizes a positive feedback mechanism to activate FLI1 by inducing DNA hypomethylation in CpG islands of the promoter. FECR1 binds to the FLI1 promoter in cis and recruits TET1, a demethylase that is actively involved in DNA demethylation. FECR1 also binds to and downregulates in trans DNMT1, a methyltransferase that is essential for the maintenance of DNA methylation.
These data suggest that FECR1 circular RNA acts as an upstream regulator to control breast cancer tumor growth by coordinating the regulation of DNA methylating and demethylating enzymes. Thus, FLI1 drives tumor metastasis not only through the canonical oncoprotein pathway, but also by using epigenetic mechanisms mediated by its exonic circular RNA.
Cancer susceptibility candidate 2 (CASC2), a recently discovered long non‐coding RNA (lncRNA), was confirmed to play numerous roles in several human cancers. However, the involvement and concrete ...mechanism of CASC2 in hepatocellular carcinoma (HCC) still need to be further elucidated. The relative expressions of CASC2 and miR‐24‐3p in HCC tissue and cell lines were determined by quantitative real‐time PCR (qRT‐PCR). The effects of CASC2 and miR‐24‐3p on HCC cells were further assessed via cell viability and apoptosis. In vivo tumorigenesis assay was performed to verify the inhibition effect of CASC2 on the tumor growth and further clarify the important role of miR‐24‐3p in this mechanism. Compared with the paired normal tissues, the relative expression of CASC2 significantly reduced in the HCC tissues, while miR‐24‐3p as determined by qRT‐PCR obviously increased in the HCC tissues. This observation was also found in HCC cell lines. Meanwhile, the expression of CASC2 was negatively related to miR‐24‐3p expression in the HCC tissues (r = −0.804, P < 0.001). CASC2 could negatively regulate the expression of miR‐24‐3p in vitro. Moreover, CASC2 overexpression resulted in the growth inhibitory and apoptosis‐inducing effects on HCC cells, but the up‐regulation of miR‐24‐3p greatly eliminated the CASC2‐induced effects. The tumorigenesis of HCC cells was restrained significantly by CASC2 overexpression as shown by decreased tumor volume and growth rate. However, miR‐24‐3p up‐regulation rescued the inhibition of CASC2 on the tumor growth in tumor‐bearing mice. LncRNA CASC2 inhibited the viability and induced the apoptosis of HCC cells through regulating miR‐24‐3p.
We investigated the involvement and concrete mechanism of CASC2 in HCC. CASC2 inhibited the viability and induced the apoptosis of HCC cells. The role of CASC2 in cell tumorigenesis was mediated by miR‐24‐3p.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract Chloroquine (CQ) and hydroxychloroquine (HCQ), two antimalarial drugs, are suggested to have potential anticancer properties. in the present study, we investigated the effects of CQ and HCQ ...on cell growth of bladder cancer with emphasis on autophagy inhibition and apoptosis induction in vitro . The results showed that CQ and HCQ inhibited the proliferation of multiple human bladder cell lines (including RT4, 5637, and T24) in a time- and dose-dependent fashion, especially in advanced bladder cancer cell lines (5637 and T24) compared to immortalized uroepithelial cells (SV-Huc-1) or other reference cancer cell lines (PC3 and MCF-7). We found that 24-hour treatment of CQ or HCQ significantly decreased the clonogenic formation in 5637 and T24 cells compared to SV-Huc-1. As human bladder cancer tumor exhibits high basal level of autophagic activities, we detected the autophagic flux in cells treated with CQ and HCQ, showing an alternation in LC3 flux in CQ- or HCQ-treated cells. Moreover, bladder cancer cells treated with CQ and HCQ underwent apoptosis, resulting in increased caspase 3/7 activities, increased level of cleaved poly(ADP-ribose) polymerase (PARP), caspase 3, and DNA fragmentation. Given these results, targeting autophagy with CQ and HCQ represents an effective cancer therapeutic strategy against human bladder cancer.
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FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Chromatin looping is key to gene regulation, yet no broadly applicable methods to selectively modify chromatin loops have been described. We have engineered a method for chromatin loop reorganization ...using CRISPR-dCas9 (CLOuD9) to selectively and reversibly establish chromatin loops. We demonstrate the power of this technology to selectively modulate gene expression at targeted loci.
Given advancements in cancer immunity, cancer treatment has gained breakthrough developments. Immune checkpoint inhibitors, such as programmed cell death 1 (PD-1) inhibitors, are the most promising ...drugs in the field and have been approved to treat various types of cancer, such as metastatic melanoma, head and neck squamous cell carcinoma, and urothelial carcinoma. However, whether PD-1 inhibitors should be administered to renal transplant patients with advanced cancer remains unclear because the T-cells produced after administration of these inhibitors act against not only tumor antigens but also donor alloantigens. Thus, the use of PD-1 inhibitors in kidney-transplanted patients with advanced cancer is limited on account of the high risk of graft failure due to acute rejection. Hence, finding optimal treatment regimens to enhance the tumor-specific T-cell response and decrease T-cell-mediated alloreactivity after administration of a PD-1 inhibitor is necessary. Thus far, no recommendations for the use of PD-1 inhibitors to treat cancer in renal transplant patients are yet available, and very few cases reporting kidney-transplanted patients treated with PD-1 inhibitors are available in the literature. Therefore, in this work, we review the published cases and suggest feasible approaches for renal transplant patients with advanced malignancy treated by a PD-1 inhibitor. Of the 22 cases we obtained, four patients maintained intact grafts without tumor progression after treatment with a PD-1 inhibitor. Among these patients, one maintained steroid dose before initiation of anti-PD1, two received immunosuppressive regimens with low-dose steroid and calcineurin inhibitor (CNI)-elimination with sirolimus before initiation of anti-PD-1 therapy, and one received combined anti-PD-1, anti-vascular endothelial growth factor (VEGF), and chemotherapy with unchanged immunosuppressive regimens. mammalian target of rapamycin (mTOR) inhibitors and anti-VEGF may act as regulators of tumor-specific and allogenic T-cells. However, more studies are necessary to explore the optimal therapy and ensure the safety and efficacy of PD-1 inhibitors in kidney-transplanted patients.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
TRPA1, a nonselective cation channel, is expressed in sensory afferent that innervates peripheral targets. Neuronal TRPA1 can promote tissue repair, remove harmful stimuli and induce protective ...responses via the release of neuropeptides after the activation of the channel by chemical, exogenous, or endogenous irritants in the injured tissue. However, chronic inflammation after repeated noxious stimuli may result in the development of several diseases. In addition to sensory neurons, TRPA1, activated by inflammatory agents from some non-neuronal cells in the injured area or disease, might promote or protect disease progression. Therefore, TRPA1 works as a molecular sentinel of tissue damage or as an inflammation gatekeeper. Most kidney damage cases are associated with inflammation. In this review, we summarised the role of TRPA1 in neurogenic or non-neurogenic inflammation and in kidney disease, especially the non-neuronal TRPA1. In in vivo animal studies, TRPA1 prevented sepsis-induced or Ang-II-induced and ischemia-reperfusion renal injury by maintaining mitochondrial haemostasis or via the downregulation of macrophage-mediated inflammation, respectively. Renal tubular epithelial TRPA1 acts as an oxidative stress sensor to mediate hypoxia-reoxygenation injury in vitro and ischaemia-reperfusion-induced kidney injury in vivo through MAPKs/NF-kB signalling. Acute kidney injury (AKI) patients with high renal tubular TRPA1 expression had low complete renal function recovery. In renal disease, TPRA1 plays different roles in different cell types accordingly. These findings depict the important role of TRPA1 and warrant further investigation.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Bladder cancer (BC) is the second most common urologic malignancy and the ninth most common malignancy worldwide. Surgical resection is the mainstay of treatment for patients with early-stage ...disease, whereas therapeutic options are limited for patients with advanced-stage or residual BC. Programmed cell death ligand-1 (PD-L1) is an important target for immunotherapy. It is known that PD-L1 is overexpressed in BC; a clinical trial involving PD-L1 immune checkpoint inhibitors in advanced BC is ongoing. In the present study, we used Western blot and quantitative real-time PCR (qPCR) to define the expression level of PD-L1 after cisplatin treatment in BC-derived cell lines. The signal activation was also evaluated by Western blot in BC-derived cell lines. We found that chemotherapeutic drug cisplatin can induce PD-L1 but not PD-L2 expression in BC-derived cell lines. Furthermore, the expression level of PD-L1 was increased in a dose- and time-dependent manner after cisplatin treatment. The cisplatin-induced PD-L1 expression is mainly mediated by ERK1/2 but not Akt/mTOR signal pathway. Moreover, we found that cisplatin activates transcription factor activator protein-1 (AP-1) to regulate PD-L1 expression. The chemotherapy drug such as cisplatin may trigger resistance of BC through PD-L1 up-regulation. The present study suggests that PD-L1 antibody should be used concomitantly with chemotherapy in the setting of advanced and metastatic BC.
Benzyl isothiocyanate (BITC), a bioactive natural product present in cruciferous vegetables, has been proved to prevent cancer progression through various mechanisms. In our previous report, we ...proved that BITC exhibits antitumor effects in bladder cancer by suppressing IGF1R, FGFR3, and mTOR, which is mediated by miR‐99a expression. In this study, we identified the signal pathway involved in regulating miR‐99a expression after BITC exposure in bladder cancer. Treatment with different BITC concentrations resulted in induction of miR‐99a expression in bladder cancer cell lines. Activation of extracellular signal‐regulated protein kinase (ERK) and c‐jun N‐terminal kinase was observed in bladder cancer after BITC treatment for 24 hours. Interestingly, by using a chemical inhibitor of candidate pathways, we found that only the ERK signal pathway is required for miR‐99a expression. Furthermore, we evaluated the transcription factor that may contribute to miR‐99a expression in response to BITC treatment. The results indicated that c‐Jun/AP‐1 was activated after BITC treatment. Moreover, we confirmed c‐Jun/AP‐1 activation through immunofluorescence and the luciferase reporter assay. The results showed that BITC treatment markedly improved nuclear translocation of c‐Jun/AP‐1 and luciferase activity dose dependently. Finally, pretreatment with the ERK inhibitor U0126 diminished c‐Jun phosphorylation and transcriptional activation, suggesting that BITC elicits ERK/c‐Jun signal transduction, which is responsible for miR‐99a expression in bladder cancer. The present work identifies the mechanism involved in upregulation miR‐99a after BITC treatment, which provides an explanation for BITC biological function in our previous work.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
This paper presents a reinforcement learning backstepping‐based control scheme for the design of a full vehicle active suspension system such that both the superior ride comfort and stabilization are ...achieved. It is well known that the traditional backstepping control scheme is suitable to solve higher order nonlinear system based on the strict‐feedback form; however, the disadvantage of the procedure requires computing the derivatives of virtual control signals, which is a very complex task. Therefore, a reinforcement learning scheme using the deep deterministic policy gradient (DDPG) control strategy is developed to replace the process of finding virtual control force in backstepping method. It not only avoids the complexity of analytically calculating the derivatives of the virtual control signals, but also retains the systems robustness when there exist random disturbances from road irregularities. To verify the performance of the proposed active suspension control scheme, the random road unevenness profiles according to ISO 8608 is considered as vertical and lateral disturbance input excitation of a full‐vehicle suspension system. Compared with conventional passive suspension system and backstepping control scheme, the proposed approach can be demonstrated to not only effectively improve ride comfort under random road excitation, but also improve the transient response and robustness.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Cisplatin-based chemotherapy is the first line treatment for several cancers including bladder cancer (BC). Autophagy induction has been implied to contribute to cisplatin resistance in ovarian ...cancer; and a high basal level of autophagy has been demonstrated in human bladder tumors. Therefore, it is reasonable to speculate that autophagy may account for the failure of cisplatin single treatment in BC. This study investigated whether cisplatin induces autophagy and the mechanism involved using human BC cell lines.
Human BC cells (5637 and T24) were used in this study. Cell viability was detected using water soluble tetrazolium-8 reagents. Autophagy induction was detected by monitoring the levels of light chain 3 (LC3)-II and p62 by Western blot, LC3-positive puncta formation by immunofluorescence, and direct observation of the autophagolysosome (AL) formation by transmission electron microscopy. Inhibitors including bafilomycin A1 (Baf A1), chloroquine (CQ), and shRNA-based lentivirus against autophagy-related genes (ATG7 and ATG12) were utilized. Apoptosis level was detected by caspase 3/7 activity and DNA fragmentation.
Cisplatin decreased cell viability and induced apoptosis of 5637 and T24 cells in a dose-and time-dependent manner. The increased LC3-II accumulation, p62 clearance, the number of LC3-positive puncta, and ALs in cisplatin-treated cells suggested that cisplatin indeed induces autophagy. Inhibition of cisplatin-induced autophagy using Baf A1, CQ, or ATG7/ATG12 shRNAs significantly enhanced cytotoxicity of cisplatin toward BC cells. These results indicated that cisplatin induced protective autophagy which may contribute to the development of cisplatin resistance and resulted in treatment failure. Mechanistically, upregulation of beclin-1 (BECN1) was detected in cisplatin-treated cells, and knockdown of BECN1 using shRNA attenuated cisplatin-induced autophagy and subsequently enhanced cisplatin-induced apoptosis.
Collectively, the study results indicated that cisplatin-induced autophagy is mediated by BECN1 in BC cells. Therefore, combinative treatment using cisplatin and autophagy inhibitors could potentially overcome cisplatin resistance related to autophagy induction.
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