Identification of topoisomerase 2A as a novel bone metastasis-related gene in liver hepatocellular carcinoma.

BACKGROUND: Bone is the second most frequent site of metastasis for Liver hepatocellular carcinoma (LIHC), which leads to an extremely poor prognosis. Identifying novel biomarkers and therapeutic targets for LIHC patients with bone metastasis is urgently needed. METHODS: In this study, we used multiple databases for comprehensive bioinformatics analysis, including TCGA, GEO, ICGC, GTEx, TISIDB, and TIMER, to identify key genes related to bone metastasis of LIHC. Clinical tissues and tissue microarray were adopted to assess the expression of TOP2A through qRT-PCR and immunohistochemistry analyses in LIHC. Gene enrichment analysis, DNA methylation, gene mutation, prognosis, and tumor immunity associated with TOP2A in LIHC were investigated. In vitro and in vivo experiments were performed to explore the functional role of TOP2A in LIHC bone metastasis. RESULTS: We identified that TOP2A was involved in LIHC bone metastasis. Clinically, TOP2A was highly expressed in LIHC tumoral specimens, with the highest level in the bone metastasis lesions. TOP2A was an independent prognostic factor that higher expression of TOP2A was markedly associated with poorer prognosis in LIHC. Moreover, the abnormal expression of TOP2A might be related to DNA hypomethylation, often accompanied by TP53 mutation, immune escape and immunotherapy failure. Enrichment analysis and validation experiments unveiled that TOP2A stimulated the Hippo-YAP signaling pathway in LIHC. Functional assays confirmed that TOP2A could promote bone-specific metastatic potential and tumor-induced osteolysis in LIHC. CONCLUSIONS: These findings unveil that TOP2A might be a novel prognostic biomarker and therapeutic target for LIHC bone metastasis.

Aspirin triggers ferroptosis in hepatocellular carcinoma cells through restricting NF-κB p65-activated SLC7A11 transcription.

A number of studies have shown that aspirin, as commonly prescribed drug, prevents the development of hepatocellular carcinoma (HCC). Ferroptosis as a dynamic tumor suppressor plays a vital role in hepatocarcinogenesis. In this study we investigated whether aspirin affected ferroptosis in liver cancer cells. RNA-seq analysis revealed that aspirin up-regulated 4 ferroptosis-related drivers and down-regulated 5 ferroptosis-related suppressors in aspirin-treated HepG2 cells. Treatment with aspirin (4 mM) induced remarkable ferroptosis in HepG2 and Huh7 cells, which was enhanced by the ferroptosis inducer erastin (10 µM). We demonstrated that NF-κB p65 restricted ferroptosis in HepG2 and Huh7 cells through directly binding to the core region of SLC7A11 promoter and activating the transcription of ferroptosis inhibitor SLC7A11, whereas aspirin induced ferroptosis through inhibiting NF-κB p65-activated SLC7A11 transcription. Overexpression of p65 rescued HepG2 and Huh7 cells from aspirin-induced ferroptosis. HCC patients with high expression levels of SLC7A11 and p65 presented lower survival rate. Functionally, NF-κB p65 blocked the aspirin-induced ferroptosis in vitro and in vivo, which was attenuated by erastin. We conclude that aspirin triggers ferroptosis by restricting NF-κB-activated SLC7A11 transcription to suppress the growth of HCC. These results provide a new insight into the mechanism by which aspirin regulates ferroptosis in hepatocarcinogenesis. A combination of aspirin and ferroptosis inducer may provide a potential strategy for the treatment of HCC in clinic.

Nectin-4 promotes osteosarcoma progression and metastasis through activating PI3K/AKT/NF-κB signaling by down-regulation of miR-520c-3p.

PURPOSE: Nectin-4 is specifically up-regulated in various tumors, exert crucial effects on tumor occurrence and development. Nevertheless, the role and molecular mechanism of Nectin-4 in osteosarcoma (OS) are rarely studied. METHODS: The expression of Nectin-4 and its relationship with clinical characteristics of OS were investigated using OS clinical tissues, tissue microarrays, TCGA, and GEO databases. Moreover, the effect of Nectin-4 on cell growth and mobility was detected by CCK-8, colony formation, transwell, and wound-healing assays. The RT-qPCR, Western blotting, and luciferase reporter assays were performed to explore molecular mechanisms through which Nectin-4 mediates the expression of miR-520c-3p, thus modulating PI3K/AKT/NF-κB signaling. In vivo mice models constructed by subcutaneous transplantation and tail vein injection were used to validate the functional roles of Nectin-4 and miR-520c-3p. RESULTS: Nectin-4 displayed a higher expression in OS tumor tissues compared with normal tissues, and its overexpression was positively associated with tumor stage and metastasis in OS patients. Functionally, Nectin-4 enhanced OS cells growth and mobility in vitro. Mechanistically, Nectin-4 down-regulated the levels of miR-520c-3p that directly targeted AKT-1 and P65, thus leading to the stimulation of PI3K/AKT/NF-κB signaling. In addition, the expression of miR-520c-3p was apparently lower in OS tissues than in normal tissues, and its low expression was significantly related to tumor metastasis. Furthermore, ectopic expression of miR-520c-3p markedly blocked the effect of Nectin-4 on OS cell growth and mobility. Knockdown of Nectin-4 could suppress the tumorigenesis and metastasis in vivo, which could be remarkably reversed by miR-520c-3p silencing. CONCLUSIONS: Nectin-4 as an oncogene can promote OS progression and metastasis by activating PI3K/AKT/NF-κB signaling via down-regulation of miR-520c-3p, which could represent a novel avenue for identifying a potential therapeutic target for improving patient outcomes.

A Novel Ferroptosis-Related Long Non-Coding RNA Prognostic Signature Correlates With Genomic Heterogeneity, Immunosuppressive Phenotype, and Drug Sensitivity in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) with high heterogeneity is a common malignancy worldwide, but effective treatments are limited. Ferroptosis plays a critical role in tumors as a novel iron-dependent and reactive oxygen species-reliant type of cell death. Several studies have shown that long non-coding RNAs (lncRNAs) can drive HCC initiation and progression. However, the prognostic value of ferroptosis-related lncRNAs in patients with HCC has not been explored comprehensively. Gene set variation analysis (GSVA) based on gene set and RNA-seq profiles obtained from public databases indicated that ferroptosis is suppressed in HCC patients. Ferroptosis-related differentially expressed lncRNAs were screened by Pearson's test. Univariate Cox regression, least absolute shrinkage and selection operator (LASSO) regression, and multivariate Cox regression were performed to establish a novel five ferroptosis-related lncRNA signature in the training cohort with 60% patients, which was further verified in the testing cohort with 40% patients. Dimensionality reduction analysis, Kaplan-Meier curve, receiver operating characteristic (ROC) curve, independent prognostic analysis, and stratification analysis confirmed that our signature had a high clinical application value in predicting the overall survival of HCC patients. Compared to the clinicopathological factors and the other four published HCC prognostic signatures, the current risk model had a better predictive value. The comparison results of functional enrichment, tumor immune microenvironment, genomic heterogeneity, and drug sensitivity between the high- and low-risk groups showed that the risk score is associated with extensive genomic alterations, immunosuppressive tumor microenvironment, and clinical treatment response. Finally, cell experiments showed that silencing LNCSRLR expression inhibited the growth, proliferation, migration, and invasion of the HCC cell line. Thus, the model can function as an efficient indicator for predicting clinical prognosis and treatment of anticancer drugs in HCC patients.

Maternal embryonic leucine zipper kinase serves as a poor prognosis marker and therapeutic target in osteosarcoma.

Osteosarcoma is the most common primary malignancy of bones and frequently affects young children and adolescents. There are several challenges associated with treating osteosarcoma owing to the aggressiveness of the disease, as well as the risk of chemoresistance. Numerous studies are being performed with the aim of identifying improved prognostic and therapeutic markers for this malignancy. Maternal embryonic leucine zipper kinase (MELK) is an oncogene that has been studied in several types of cancer in recent years. In the present study, the expression of MELK in osteosarcoma and normal tissue samples was examined, and the effects of MELK expression on osteosarcoma cellular proliferation, metastasis, the cell cycle and apoptosis were demonstrated using CCK­8, wound healing, migration and invasion and apoptosis assays. The role of MELK in cancer progression in osteosarcoma was determined, revealing the association between MELK expression and prognosis of osteosarcoma. It was demonstrated that knockdown of MELK resulted in reduced proliferation, migration and invasion in vitro along with potentiation of apoptosis and cell cycle arrest. Furthermore, the effect of the targeted MELK inhibitor, OTSSP167, on tumor progression of osteosarcoma in vitro and in vivo was assessed. Mechanistically, it was demonstrated that MELK promoted osteosarcoma proliferation and metastasis by regulating PCNA and MMP9 expression via the PI3K/Akt/mTOR signaling pathway. Thus, the present study revealed the oncogenic role played by MELK, and established MELK as a valuable prognostic and therapeutic marker in osteosarcoma.

MARK2 enhances cisplatin resistance via PI3K/AKT/NF-κB signaling pathway in osteosarcoma cells.

Osteosarcoma is the most common primary bone malignancy found in children and young adults. Chemotherapy resistance, especially to cisplatin, presents a major clinical challenge in the treatment and prognosis of osteosarcoma. New biomarkers and mechanisms of cisplatin resistance in osteosarcoma are urgently needed due to poor survival outcomes and currently inadequate treatments. In this study, we investigate the role and potential mechanisms of microtubule-affinity regulating kinase2 (MARK2) during osteosarcoma cisplatin resistance. Gene Expression Omnibus dataset analyses indicated that high MARK2 expression was associated with poor prognosis and may positively correlate with chemoresistance. Moreover, we showed that MARK2 was significantly upregulated in osteosarcoma cells compared with normal cells. The overexpression and inhibition of MARK2 promoted and suppressed, respectively, cisplatin resistance in osteosarcoma cells in vitro and in vivo. Mechanistically, MARK2 overexpression enhanced P-glycoprotein expression and decreased cell apoptosis through PI3K/AKT/NF-κB signaling pathway activation, resulting in cisplatin resistance. Our results suggest that high MARK2 expression can enhance cisplatin resistance in osteosarcoma cells, supporting the potential of MARK2 as a new therapeutic target and biomarker for predicting cisplatin resistance in osteosarcoma.

The inhibition of MARK2 suppresses cisplatin resistance of osteosarcoma stem cells by regulating DNA damage and repair.

OBJECTIVE: This study aims to explore the role of MARK2 in chemotherapeutic resistance and potential mechanism within cisplatin resistance models of CD133+ MG-63 and MNNG/HOS cells. METHODS: CD133- and CD133+ MG-63 and MNNG/HOS cells were differentiated and obtained by MACS(Magnetic bead sorting). Cell activity was determined by CCK-8 assay. siRNA was employed to down regulate the Microtubule Affinity Regulated Kinase 2 (MARK2) expression. Immunofluorescence detection and RT-qPCR were used to measure the expressions of MARK2 and DNA-PKcs at both protein and mRNA levels. Western blot was applied to test the levels of MARK2, γH2AX (S139), DNA-PKcs, Phospho-PI3 Kinase p85 (Tyr458), Akt, phospho-Akt (T308) antibodies, mTOR, phospho-mTOR (Ser2448). RESULTS: Compared with CD133- MG-63 cells, CD133+ MG-63 cells showed significantly strong cisplatin resistance, with high levels of MARK2, DNA-PKcs and potent DNA damage repair ability (p<0.05). Down regulation of MARK2 reduced the cisplatin resistance of CD133+ MG-63 cells, with deceasing expression of DNA-PKcs (p<0.05). PI3K/Akt/mTOR pathway was potentially activated in CD133+ MG-63 cells, and involved in the cisplatin resistance of MG-63 cells. The similar results were observed in CD133+ MNNG/HOS cells. The reduction of MARK2 retarded the activity of PI3K/Akt/mTOR pathway and further impeded the cisplatin resistance in CD133+ MG-63 and MNNG/HOS cell. CONCLUSION: Our data suggested that MARK2 was related to cisplatin resistance in CD133+ MG-63 and MNNG/HOS cells. The decrease of MARK2 restricted the cisplatin resistance of CD133+ MG-63 and MNNG/HOS cells by down regulating the expression of DNA dependent protein kinase catalytic subunit (DNA-PKcs) and inhibiting activity of PI3K/Akt/mTOR signaling pathway, which provides new clues for the osteosarcoma chemotherapy strategy.

Non-Volatile Transistor Memory with a Polypeptide Dielectric.

Organic nonvolatile transistor memory with synthetic polypeptide derivatives as dielectric was fabricated by a solution process. When only poly (γ-benzyl-l-glutamate) (PBLG) was used as dielectric, the device did not show obvious hysteresis in transfer curves. However, PBLG blended with PMMA led to a remarkable increase in memory window up to 20 V. The device performance was observed to remarkably depend on the blend ratio. This study suggests the crystal structure and the molecular alignment significantly affect the electrical performance in transistor-type memory devices, thereby provides an alternative to prepare nonvolatile memory with polymer dielectrics.

Mechanism of Action of Periplogenin on Nasopharyngeal Carcinoma Based on Network Pharmacology and Experimental Study of Vitamin E Coupled with Periplogenin Self-Assembled Nano-Prodrug for Nasopharyngeal Carcinoma.

Periplogenin is a compound extracted from cortex periplocae. In the monomers' screening for inhibiting nasopharyngeal carcinoma, we found that periplogenin can inhibit nasopharyngeal carcinoma; however, its mechanism is still unclear. In this study, the chemical structure of periplogenin was uploaded to the PubChem database in order to obtain the target of periplogenin. The NPC's differential genes were obtained by analyzing the nasopharyngeal carcinoma data in the GEO database by R software. The common target of periplogenin and nasopharyngeal carcinoma was obtained through Cytoscape. Through R software analysis, ALB, epidermal growth factor receptor (EGFR), MAPK1, ESR1, MAPK8, SRC, CASP3, HSP90AA1, AR, MAPK14 may be the main targets of periplogenin in NPC. Through go enrichment analysis, it was found that periplogenin acted mainly on nasopharyngeal carcinoma through response to steroid metabolic process, cellular response to steroid hormone stimulus, hormone-mediated, and steroid hormone signaling pathway. After enrichment analysis on the Kyoto Encyclopedia of Genes and Genomes pathway, it was found that periplocan may inhibit NPC through the MAPK signaling pathway (the main signaling pathway), and the signaling pathway of proteoglycans in cancer, and the PI3K/AKT signaling pathway as well. In this study, we also carried out the experimental study of vitamin E together with periplogenin self-assembled nano-prodrugs in the treatment of NPC, and the results showed that tumor weight of PBS group was 0.531±0.039 g, while that of PPG group and MPSSV-NPs group was 0.258±0.059 g and 0.169±0.033 g, respectively, which was lower than PBS group. And the tumor inhibition rate of MPSSV-NPs was 69.41%, which was significantly higher than that of the PPG group (51.38%). This study demonstrated the mechanism of inhibition of nasopharyngeal carcinoma (NPC) by the monomer of periplogenin based on network pharmacology. We preliminarily confirmed that vitamin E coupled with a periplogenin self-assembled nano-prodrug has obvious effect in treating nasopharyngeal carcinoma.

Preparation and Characterization of Acylcaramel.

Caramel is a widely used water-soluble food pigment. The acylation of caramel was conducted by aliphatic acyl chlorides with different chain lengths. Acetyl, butyryl, octyl, lauryl, palmityl, and stearyl caramels were prepared with the ratio of acyl chloride/caramel of 6. The formation of acylated caramel was confirmed by Fourier transform infrared spectra, and the acyl mass fraction in acylcaramel was determined by potentiometric titration. Thermal analysis showed that the weight loss of acylated caramel was higher than that of raw caramel. The scanning electron microscopy analysis showed that the morphology of acylated caramel was significantly different from that of raw material. The acyl mass fraction of acylated caramel increased with the increase of acyl chain lengths. Meanwhile, the lipo-hydro partition coefficient, the solubility in corn oil, and color, red, and yellow indexes increased with the increase of the mass fraction of acyl in acylcaramel. It was found that stearyl caramel has the highest lipid solubility of 5.73 mg/mL in corn oil; however, the color, red, and yellow indexes of palmityl caramel reached 25 818.60, 1.149, and 1.757, respectively. This study provides a method to improve the solubility of caramel in lipid phase and expand the application range of caramel.

Regioselective Substitution at the 1,3- and 6,8-Positions of Pyrene for the Construction of Small Dipolar Molecules.

This article presents a novel asymmetrical functionalization strategy for the construction of dipolar molecules via efficient regioselective functionalization along the Z-axis of pyrene at both the 1,3- and 6,8-positions. Three asymmetrically substituted 1,3-diphenyl-6,8-R-disubsituted pyrenes were fully characterized by X-ray crystallography, photophysical properties, electrochemistry, and density functional theory calculations.

A universal gene carrier platform for treatment of human prostatic carcinoma by p53 transfection.

Our previous work showed that a charge-reversal layer-by-layer nanosystem, PEI/PAH-Cit/AuNP-CS, effectively facilitates cellular uptake of siRNA and enhances the silencing efficacy of MDR1 siRNA. Here, the plasmid loading capacity of this vehicle was examined using EGFP-N1, and the plasmid release profile was determined in response to pH changes. The cytotoxicity of the EGFP-N1/PEI/PAH-Cit/AuNP-CS complex against HeLa and 293T cells was almost negligible. PEI/PAH-Cit/AuNP-CS efficaciously delivered the plasmids EGFP-N1 (encoding green fluorescent protein) and pGL3.0 (encoding luciferase) into 293T and HeLa cells, thus verifying the universality of PEI/PAH-Cit/AuNP-CS as a gene carrier. The results of an inverted fluorescence microscopy, flow cytometry (FCM) and western blotting methods demonstrated that PC-3 prostate cancer cells treated with EGFP-p53/PEI/PAH-Cit/AuNP-CS expressed higher levels of GFP than cells treated with EGFP-p53/PEI. Furthermore, PC-3 cells treated with EGFP-p53/PEI/PAH-Cit/AuNP-CS showed reduced cellular viability and increased nuclear fragmentation, consistent with elevated p53 expression. Propidium iodide (PI) flow cytometric assays were conducted to demonstrate that EGFP-p53/PEI/PAH-Cit/AuNP-CS elevated the level of apoptosis in PC-3 cells. Western blotting and caspase activation studies revealed that EGFP-p53/PEI/PAH-Cit/AuNP-CS complexes may induce PC-3 apoptosis via the mitochondria-mediated signaling pathway by up-regulation of Bax, down-regulation of Bcl-2, and activation of caspase-3.