Bioinformatics and system biology approach to identify the influences among COVID-19, influenza, and HIV on the regulation of gene expression.

Background: Coronavirus disease (COVID-19), caused by SARS-CoV-2, has emerged as a infectious disease, coexisting with widespread seasonal and sporadic influenza epidemics globally. Individuals living with HIV, characterized by compromised immune systems, face an elevated risk of severe outcomes and increased mortality when affected by COVID-19. Despite this connection, the molecular intricacies linking COVID-19, influenza, and HIV remain unclear. Our research endeavors to elucidate the shared pathways and molecular markers in individuals with HIV concurrently infected with COVID-19 and influenza. Furthermore, we aim to identify potential medications that may prove beneficial in managing these three interconnected illnesses. Methods: Sequencing data for COVID-19 (GSE157103), influenza (GSE185576), and HIV (GSE195434) were retrieved from the GEO database. Commonly expressed differentially expressed genes (DEGs) were identified across the three datasets, followed by immune infiltration analysis and diagnostic ROC analysis on the DEGs. Functional enrichment analysis was performed using GO/KEGG and Gene Set Enrichment Analysis (GSEA). Hub genes were screened through a Protein-Protein Interaction networks (PPIs) analysis among DEGs. Analysis of miRNAs, transcription factors, drug chemicals, diseases, and RNA-binding proteins was conducted based on the identified hub genes. Finally, quantitative PCR (qPCR) expression verification was undertaken for selected hub genes. Results: The analysis of the three datasets revealed a total of 22 shared DEGs, with the majority exhibiting an area under the curve value exceeding 0.7. Functional enrichment analysis with GO/KEGG and GSEA primarily highlighted signaling pathways associated with ribosomes and tumors. The ten identified hub genes included IFI44L, IFI44, RSAD2, ISG15, IFIT3, OAS1, EIF2AK2, IFI27, OASL, and EPSTI1. Additionally, five crucial miRNAs (hsa-miR-8060, hsa-miR-6890-5p, hsa-miR-5003-3p, hsa-miR-6893-3p, and hsa-miR-6069), five essential transcription factors (CREB1, CEBPB, EGR1, EP300, and IRF1), and the top ten significant drug chemicals (estradiol, progesterone, tretinoin, calcitriol, fluorouracil, methotrexate, lipopolysaccharide, valproic acid, silicon dioxide, cyclosporine) were identified. Conclusion: This research provides valuable insights into shared molecular targets, signaling pathways, drug chemicals, and potential biomarkers for individuals facing the complex intersection of COVID-19, influenza, and HIV. These findings hold promise for enhancing the precision of diagnosis and treatment for individuals with HIV co-infected with COVID-19 and influenza.

[Mechanism Research of lncRNA miR143HG on Regulating the Biological Behavior 
of Lung Squamous Cell Carcinoma H520 Cells].

BACKGROUND: There is a high morbidity, mortality, and poor clinical prognosis of lung squamous cell carcinoma (LUSC). However, there is currently no effective targeted treatment plan for LUSC. As a long non-coding RNA (lncRNA), lncRNA miR143HG has been proven to play an important role in the occurrence and development of various tumors. However, the biological role played by lncRNA miR143HG in LUSC cells is still unclear. Therefore, this study aimed to investigate the mechanism of lncRNA miR143HG on regulating the biological behavior of LUSC H520 cells. METHODS: Pan-cancer analysis and differential expression analysis of lncRNA miR143HG were performed based on The Cancer Genome Atlas (TCGA) database. The predictive effect of lncRNA miR143HG on the diagnosis and prognosis of LUSC was evaluated by adopting the receiver operating characteristic (ROC) curve and timeROC curve. The enrichment degree of each pathway to lncRNA miR143HG was determined. The expression of lncRNA miR143HG and miR-155 in BEAS-2B cells and H520 cells was detected using quantitative real-time polymerase chain reaction (qRT-PCR). H520 cells were randomly divided into blank control group (without any treatment), negative control group (transfected with lncRNA-NC), lncRNA miR143HG group (transfected with lncRNA miR143HG), and lncRNA miR143HG+miR-155 group (co-transfected with lncRNA miR143HG and miR-155). The approaches of CCK-8, wound healing test, Transwell assay, flow cytometry, qRT-PCR, and Western blot were respectively employed to detect the cell proliferation ability, cell migration ability, cell invasion ability, cell apoptosis rate, and expression level of related genes and proteins of the Wnt/ß-Catenin pathway. RESULTS: The results of pan-cancer analysis and differential analysis collectively showed that except for renal clear cell carcinoma, the expression of lncRNA miR143HG in other cancer tissues was higher than that in healthy tissues, and the differences were significant in LUSC. The evaluation results of the ROC curve and timeROC curve suggested that lncRNA miR143HG was of great significance in the prediction of diagnosis and prognosis of LUSC. The pathways enriched in high expression of lncRNA miR143HG mainly included focal adhesion, vascular smooth muscle contraction, calcium signaling pathways, and so on; the pathways enriched in the low expression of lncRNA miR143HG embraced oxidative phosphorylation, cell cycle, basic transcription factors, etc. The qRT-PCR results showed that lncRNA miR143HG was low expressed but miR-155 was highly expressed in H520 cells when compared to BEAS-2B cells (P<0.05). Compared with the negative control group, the expression levels of the gene of lncRNA miR143HG, the gene and protein of Wnt, as well as the gene and protein of ß-Catenin were significantly increased, while the gene expression of miR-155, the ability of cell proliferation, cell migration, and cell invasion were significantly reduced, but the cell apoptosis rate was dominantly elevated in cells of lncRNA miR143HG group (P<0.05). In addition, compared with the lncRNA miR143HG group, overexpression of miR-155 could reverse the biological behavior mediated by lncRNA miR143HG, and the difference was statistically significant (P<0.05). CONCLUSIONS: LncRNA miR143HG was of great significance for the biological behavior of H520 cells. LncRNA miR143HG inhibited the ability of proliferation, migration, and invasion, as well as enhanced the apoptosis of H520 cells by downregulating miR-155 expression, which may be related to the Wnt/ß-Catenin pathway.
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Cytotoxic Steroidal Saponins Containing a Rare Fructosyl from the Rhizomes of Paris polyphylla var. latifolia.

A phytochemical investigation of the steroidal saponins from the rhizomes of Paris polyohylla var. latifolia led to the discovery and characterization of three new spirostanol saponins, papolatiosides A-C (1-3), and nine known compounds (4-12). Their structures were established via extensive spectroscopic data analysis and chemical methods. Interestingly, compounds 1 and 2 possessed a fructosyl in their oligosaccharide moiety, which is rare in natural product and was firstly reported in family Melanthiaceae. The cytotoxicity of these saponins against several human cancer cell lines was evaluated by a CCK-8 experiment. As a result, compound 1 exhibited a significant cytotoxic effect on LN229, U251, Capan-2, HeLa, and HepG2 cancer cells with IC50 values of 4.18 ± 0.31, 3.85 ± 0.44, 3.26 ± 0.34, 3.30 ± 0.38 and 4.32 ± 0.51 µM, respectively. In addition, the result of flow cytometry analysis indicated that compound 1 could induce apoptosis of glioma cells LN229. The underlying mechanism was explored by network pharmacology and western bolt experiments, which indicated that compound 1 could induce glioma cells LN229 apoptosis by regulating the EGFR/PI3K/Akt/mTOR pathway.

New steroidal saponins from the roots of Paris verticillata.

Four new polyhydroxylated steroidal saponins, parisverticillatosides A-D (1-4), together with four known spirostanol saponins (5-8) were isolated from the roots of Paris verticillata. Their structures were elucidated on the basis of extensive spectroscopic analysis and chemical evidences. The discovery of the new compounds 1-4 extended the diversity and complexity of this spirostanol saponin family. The saponins 5 and 6 exhibited cytotoxicities against two human glioma cell lines.

Three New Steriodal Saponins from the Rhizomes of Tupistra chinensis Baker.

The phytochemical constituent investigation on the 70 % ethanol extract of the rhizomes of Tupistra chinensis Baker resulted in the isolation of three new steroidal saponins which were named tuchinosides A-C (1-3). Their structures were determined by extensive spectrum analysis and chemical evidence, especially 2D NMR and HR-ESI-MS techniques. In addition, the cytotoxicity of compounds 1-3 against several human cancer cell lines was evaluated.

Steriodal saponins from the rhizomes of Tupistra chinensis Baker.

Chemical constituent investigation on the n-BuOH extract of the rhizomes of Tupistra chinensis Baker leads to the isolation of ten compounds including eight undescribed furostanol saponins, tupischinosides A - H, and two known ones. The structures of isolated compounds were determined by extensive spectral analysis and chemical evidences. Interestingly, tupischinosides A and B, C and D, E and F, G and H were identified as four pairs of epimers. The cytotoxicity of tupischinosides A - H against human cancer cell lines U87, SHG44, U251, LN229 and HepG-2 was evaluated by CCK-8 method. As a result, tupischinosides A and C exhibited significant proliferation inhibitory effect on the tested cancer cells. On the contrary, the corresponding epimers, tupischinosides B and D, which only differ in the configuration of C-23 didn't exhibit any cytotoxicity to cancer cells. These results indicated that the stereochemistry of C-23 was crucial to the activity of the compounds.

Cytotoxic steroidal glycosides from the rhizomes of Paris polyphylla var. yunnanensis.

Paris polyphylla var. yunnanensis (Franch.) Hand.-Mazz. (Melanthiaceae), an important specie of the genus Paris, has long been in a traditional Chinese medicine (TCM) for a long time. This study aimed to isolate and identify the structures of bioactive saponins from the rhizomes of P. polyphylla var. yunnanensis and evaluate their cytotoxicity against BxPC-3, HepG2, U373 and SGC-7901 carcinoma cell lines. Seven previously undescribed and seven known saponins were identified, and Paris saponins VII (PSVII) showed significant cytotoxicity against the BxPC-3 cell line with IC50 values of 3.59 µM. Furthermore, flow cytometry, transmission electron microscopy and western-bolt analysis revealed that PSVII inhibited the proliferation of BxPC-3 cells and might be involved in inducing apoptosis and pyroptosis by activating caspase-3, -7 and caspase-1, respectively.

In Situ Biomimetic Mineralization of Bone-Like Hydroxyapatite in Hydrogel for the Acceleration of Bone Regeneration.

A critical-sized bone defect, which cannot be repaired through self-healing, is a major challenge in clinical therapeutics. The combination of biomimetic hydrogels and nano-hydroxyapatite (nano-HAP) is a promising way to solve this problem by constructing an osteogenic microenvironment. However, it is challenging to generate nano-HAP with a similar morphology and structure to that of natural bone, which limits the improvement of bone regeneration hydrogels. Inspired by our previous works on organic-inorganic cocross-linking, here, we built a strong organic-inorganic interaction by cross-linking periosteum-decellularized extracellular matrix and calcium phosphate oligomers, which ensured the in situ mineralization of bone-like nano-HAP in hydrogels. The resulting biomimetic osteogenic hydrogel (BOH) promotes bone mineralization, construction of immune microenvironment, and angiogenesis improvement in vitro. The BOH exhibited acceleration of osteogenesis in vivo, achieving large-sized bone defect regeneration and remodeling within 8 weeks, which is superior to many previously reported hydrogels. This study demonstrates the important role of bone-like nano-HAP in osteogenesis, which deepens the understanding of the design of biomaterials for hard tissue repair. The in situ mineralization of bone-like nano-HAP emphasizes the advantages of inorganic ionic oligomers in the construction of organic-inorganic interaction, which provides an alternative method for the preparation of advanced biomimetic materials.

The alkaloids with neuroprotective effect from the root bark of Ailanthus altissima.

The chemical constituent investigation on the root bark of Ailanthus altissima leads to the isolation of a new ß-carboline alkaloid, 14(S),15-dihydroxy-6-methoxy-ß-carboline (1), along with nine known alkaloids. The structure of new compound was elucidated on basis of extensive spectroscopic analysis, especially two-dimensional (2D) NMR techniques and the absolute configuration of C-14 was determined by ECD calculation. The neuroprotective effect of the isolated compounds on PC12 cells against the serum deprivation injury was evaluated by MTT method. As a result, compound 7 revealed protective effect on PC12 cells and the cell survival rate was significantly increased.

Cytotoxic steroidal saponins from the rhizomes of Paris fargesii var. Petiolata.

Phytochemical investigation on the rhizomes of Paris fargesii var. petiolata (Baker ex C. H. Wright) Wang et Tang led to the isolation of five previously undescribed steroidal saponins, parpetiosides A-E (1-5), and six known analogs (6-11). Their structures were established by extensive spectroscopic data analysis and chemical methods. Compound 5 was a rare steroidal saponin with disaccharide moiety linked at C-26 of dehydrokryptogenin that was hardly seen in the genus Paris. The cytotoxicities of the isolated compounds against three human cancer cell lines (U87, HepG2 and SGC-7901) were evaluated, and compound 1 displayed certain inhibitory effect with IC50 values of 8.02 ± 0.45, 8.24 ± 0.57 and 6.20 ± 0.79 µM, respectively. Moreover, the preliminary mechanism of 1 inhibiting the proliferation of the three cancer cell lines might be related to cell cycle distribution and the induction of S phase arrest.

Biology of Rhynchaenus maculosus provides insights and implications for integrated management of this emerging pest.

Rhynchaenus maculosus is an emerging insect pest with an increasingly serious tendency. Lack of biology information results in the bottleneck of integrated management of this pest. To facilitate an available design of integrated pest management strategy, biology of R. maculosus, including voltinism, life cycle, distribution, and damage has been investigated. Results reveal that R. maculosus is oligophagous and distributes in Heilongjiang, Jilin, and Liaoning provinces, China. This pest produces one generation per year (univoltinism) and overwinters as adults in leaf litter. From mid-April to late-April, active overwintering adults emerge from overwintering sites. The next generation of adult R. maculosus appears from mid-May to early June until mid-August to early September when the beetles move into the overwintering places. The entire time span of adult occurrence ranges from 315.6 ± 3.6 to 336.4 ± 3.2 days (Mean ± SD). Larvae undergo 3 instars with a total duration of 20 to 23 days. R. maculosus larvae feed on Q. wutaishanica and Q. mongolica without host-specific preference between the two host species, but do not harm Q. acutissim. Three species of larval parasites were collected and identified as Braconidae sp., Eulophidae sp., and Ceraphronidae sp. Biological information of R. maculosus provides essential insights for design and implementation of integrated management of this pest.

CN-3 increases TMZ sensitivity and induces ROS-dependent apoptosis and autophagy in TMZ-resistance glioblastoma.

Many glioma patients develop resistance to temozolomide (TMZ) treatment, resulting in reduced efficacy and survival rates. TMZ-resistant cell lines SHG44R and U87R, which highly express O6 -methylguanine DNA methyltransferase (MGMT) and P-gp, were established. CN-3, a new asterosaponin, showed cytotoxic effects on TMZ-resistant cells in a dose- and time-dependent manner via reactive oxygen species (ROS)-mediated apoptosis and autophagy. Transmission electron microscopy and monodansylcadaverine (MDC) staining showed turgidity of the mitochondria and autophagosomes in CN-3-treated SHG44R and U87R cells. The autophagy inhibitor 3-methyladenine was used to confirm the important role of autophagy in CN-3 cytotoxicity in TMZ-resistant cells. The ROS scavenger N-acetyl- l-cysteine (NAC) attenuated the levels of ROS induced by CN-3 and, therefore, rescued the CN-3 cytotoxic effect on the viability of SHG44R and U87R cells by Cell Counting Kit-8 assays and JuLI-Stage videos. MDC staining also confirmed that NAC rescued an autophagosome increase in CN-3-treated SHG44R and U87R cells. Western blotting revealed that CN-3 increased Bax, cleaved-caspase 3, cytochrome C, PARP-1, LC3-Ⅱ, and Beclin1, and decreased P-AKT, Bcl-2, and p62. Further rescue experiments revealed that CN-3 induced apoptosis and autophagy through ROS-mediated cytochrome C, cleaved-caspase 3, Bcl-2, P-AKT, PARP-1, and LC3-Ⅱ. In addition, CN-3 promoted SHG44R and U87R cells sensitive to TMZ by reducing the expression of P-gp, MGMT, and nuclear factor kappa B p65, and it had a synergistic cytotoxic effect with TMZ. Moreover, CN-3 disrupted the natural cycle arrest and inhibited the migration of SHG44R and U87R cells by promoting cyclin E1 and D1, and by decreasing P21, P27, N-cadherin, ß-catenin, transforming growth factor beta 1, and Smad2.

Engineered osteoclasts as living treatment materials for heterotopic ossification therapy.

Osteoclasts (OCs), the only cells capable of remodeling bone, can demineralize calcium minerals biologically. Naive OCs have limitations for the removal of ectopic calcification, such as in heterotopic ossification (HO), due to their restricted activity, migration and poor adhesion to sites of ectopic calcification. HO is the formation of pathological mature bone within extraskeletal soft tissues, and there are currently no reliable methods for removing these unexpected calcified plaques. In the present study, we develop a chemical approach to modify OCs with tetracycline (TC) to produce engineered OCs (TC-OCs) with an enhanced capacity for targeting and adhering to ectopic calcified tissue due to a broad affinity for calcium minerals. Unlike naive OCs, TC-OCs are able to effectively remove HO both in vitro and in vivo. This achievement indicates that HO can be reversed using modified OCs and holds promise for engineering cells as "living treatment agents" for cell therapy.

New Steroidal Saponins Isolated from the Rhizomes of Paris mairei.

The genus Paris is an excellent source of steroidal saponins that exhibit various bioactivities. Paris mairei is a unique species and has been widely used as folk medicine in Southwest China for a long time. With the help of chemical methods and modern spectra analysis, five new steroidal saponins, pamaiosides A-E (1-5), along with five known steroidal saponins 6-10, were isolated from the rhizomes of Paris mairei. The cytotoxicity of all the new saponins was evaluated against human pancreatic adenocarcinoma PANC-1 and BxPC3 cell lines.

CN-3 induces mitochondrial apoptosis in glioma via Ros-mediated PI3K/AKT pathway.

Recently we isolated CN-3, a new asterosaponin from starfish Culcita novaeguineae, and reported that asterosaponin arrests glioma cell cycle via SCUBE3. However, the multiple mechanisms underlying CN-3 anti-glioma action remains poorly known. Thus, the focus of this study was to evaluate the inhibitory effect of CN-3 on human glioma cells and its underlying molecular mechanisms. U87 and U251 cells were incubated with various concentrations of CN-3, and CCK-8, transmission electron microscopy, ICELLigence, TUNEL, flow cytometry, N-acetyl-L-cysteine, and western blot were conducted. As a result, it was found that CN-3 significantly inhibited U87 and U251 cell viability and proliferation in a time- and dose- dependent manner, and also induced mitochondrial apoptosis. Furthermore, we detected that CN-3 downregulated PI3K, P-Akt, AKT and BCL-2, and upregulated cytochrome C and BAX in U87 and U251 cells. Moreover, ROS triggered the inhibition and cell apoptosis for CN-3 via inactivation of P-Akt and activation of cytochrome C. In conclusion, these findings suggest that CN-3 may be a promising candidate for the development of a therapy of glioma.

Promotion of Ros-mediated Bax/Cyt-c apoptosis by polyphyllin II leads to suppress growth and aggression of glioma cells.

BACKGROUND: Gliomas remain among the most difficult cancers to treat, with a 5-year overall survival no greater than 5%. Many saponins showed a wide spectrum of anti-cancer activities at low concentration. Polyphyllin II is one of the common saponins from Paris polyphylla. However, the effect of Polyphyllin II on glioma cells has not been evaluated. Objective of the present study was to investigate whether Polyphyllin II have inhibition on glioma cells, and the possible mechanisms. METHODS: The viability of U87 and U251 cells was detected by cell counting kit-8, cell counting real time cellular analysis and cell clone formation methods. Transwell was used to estimate the aggression of U87 and U251. The cell apoptosis rate was tested by flow cytometry. The morphological change was determined by transmission electron microscopy. The levels of AKT, phosphorylation of AKT, Bax, Bcl-2, cytochrome c, and cleaved caspase 3 proteins were assessed by Western blot. N-acetyl-L-cysteine was used to check the role of ROS in polyphyllin II inhibition to glioma cells. RESULTS: Polyphyllin II showed significant suppress to proliferation and aggression of U87 and U251 in a dose- and time- dependent manner. Result of flow cytometry confirmed that Polyphyllin II induced apoptosis to U87 and U251 cells. Transmission electron microscopy observation revealed majority of the glioma cells treated with Polyphyllin II had turgidity of mitochondrion, disarrangement, diminution and vacuolization, those refer to mitochondrial apoptosis. Western blot indicated that Polyphyllin II promoted cyt-c, Bax, caspase 3 and cleaved-caspase 3, and decreased Bcl-2, AKT and p-AKT. Rescue experiments using N-acetyl-L-cysteine, a reactive oxygen species scavenger, reversed the levels of Bax and cyt-c, and the inhibition in Polyphyllin II-treated U87 and U251 cells. CONCLUSIONS: The present findings revealed that polyphyllin II may be a potential drug against glioma.

Extracellular matrix scaffold crosslinked with vancomycin for multifunctional antibacterial bone infection therapy.

The treatment of acute and chronic bone infections remains a major clinical challenge. The various factors released by the bacteria, acidic environment, and bacterial colonies in the bone grooves and implanted synthetic materials collectively promote the formation of biofilms. Dormant bacteria and biofilms cause infections that are difficult to cure and that can develop chronically. Therefore, a new antibacterial material was synthesized in the present study for multifunctional bone infection therapy and consists of specific demineralized extracellular cancellous bone (SDECM) crosslinked with vancomycin (Van) by means of electrostatic interactions and chemical bonds. It was verified in vitro that the new material (Van-SDECM) not only has pH-sensitive release and biofilm inhibition properties, but also maintains sustained bactericidal ability accompanied by the degradation of the scaffold, which does not affect its favorable osteogenic performance. The infectious bone defect in vivo model further confirms the comprehensive anti-infective and osteogenic ability of the Van-SDECM. Further, these favorable properties are due to the pH-sensitive sustained release sterilization and scaffold contact antibacterial properties, accompanied by osteoclast activity inhibition, osteogenesis promotion and immunoregulation effects. This study provides a new drug-scaffold composite preparation method based on a native-derived extracellular matrix scaffold.

Preparation and Characterization of an Optimized Meniscal Extracellular Matrix Scaffold for Meniscus Transplantation.

Many studies have sought to construct a substitute to partially replace irreparably damaged meniscus. Only the meniscus allograft has been used in clinical practice as a useful substitute, and there are concerns about its longevity and inherent limitations, including availability of donor tissue and possibility of disease transmission. To overcome these limitations, we developed an acellular xenograft from whole porcine meniscus. Samples were treated with 2% Triton X-100 for 10 days and 2% sodium dodecyl sulfate for 6 days. The DNA content of extracellular matrix (ECM) scaffolds was significantly decreased compared with that of normal porcine menisci (p < 0.001). Histological analysis confirmed the maintenance of ECM integrity and anisotropic architecture in the absence of nuclei. Biochemical and biomechanical assays of the scaffolds indicated the preservation of collagen (p = 0.806), glycosaminoglycan (p = 0.188), and biomechanical properties (elastic modulus and transition stress). The scaffolds possessed good biocompatibility and supported bone marrow mesenchymal stem cells (BMSCs) proliferation for 2 weeks in vitro, with excellent region-specific recellularization in vivo. The novel scaffold has potential value for application in recellularization and transplantation strategies.

Reduction of SCUBE3 by a new marine-derived asterosaponin leads to arrest of glioma cells in G1/S.

Many saponins are characterized as exhibiting a wide spectrum of antitumor activities at low concentrations. Most of the previous studies that aimed to understand the mechanisms underlying anticancer saponins have focused on numerous classical signaling pathways. However, at the oncogene level, little is known about the action of saponins, especially asterosaponin. In this study, CN-3, a new asterosaponin isolated from the starfish Culcita novaeguineae, decreased the proliferation of U87 and U251 cells at low doses in a dose- and time-dependent manner. Microarray analysis revealed CN-3 significantly induced the differential expression of 661 genes that are related to its antiglioma effect in U251. Nine downregulated genes (SCUBE3, PSD4, PGM2L1, ACSL3, PRICKLE1, ABI3BP, STON1, EDIL3, and KCTD12) were selected, for further verification of their low expression. Then, shRNA transfection and high-content screening were performed and significantly decreased U251 cell proliferation rate was only observed for the SCUBE3 knockdown. qPCR confirmed SCUBE3 was highly expressed in U251 and U87 cells, and had medium expression levels in U373 cells. Real-time cellular analysis using iCELLigence demonstrated that SCUBE3 is an oncogene in U251 and U87 cells, with knockdown of SCUBE3 inhibiting U251 and U87 cell proliferation while, conversely, SCUBE3 overexpression promoted their proliferation. Afterward, SCUBE3 protein was found to have high expression in primary glioma specimens from patients examined by immunohistochemistry but low expression in normal brain. PathScan ELISA analysis in conjunction with TEM observation demonstrated that the effect of SCUBE3 knockdown in U251 does not appear to be related to the induction of apoptosis. Employing CCK-8, iCELLigence, flow cytometry, western blotting, and shRNA transfection (knockdown and overexpression) experiments, we reveal that the reduction of SCUBE3 expression, induced by CN-3, mediated both inhibition and G1/S arrest of U251 via the Akt/p-Akt/p53/p21/p27/E2F1 pathway.

A steroidal saponin form Paris vietnamensis (Takht.) reverses temozolomide resistance in glioblastoma cells via inducing apoptosis through ROS/PI3K/Akt pathway.

Glioblastoma is one of the most difficult cancers to treat with a 5-year overall survival rate less than 5%. Temozolomide (TMZ) is an effective drug for prolonging the overall survival time of patients, while drug-resistance is an important clinical problem at present. Pennogenin-3-α-L-rhamnopyranosyl-(1→4)-[α-Lrhamno-pyranosyl-(1→2)]- ß-D-glucopyranoside (N45), a steroidal saponin, was isolated from the rhizomes of Paris vietnamensis (Takht.), which is used as a Traditional Chinese Medicine and has been reported to possess preclinical anticancer efficacy in various cancer types. However, the mechanism of the inhibition of N45 on glioblastoma cells and its possible application in the treatment of chemotherapy-resistant glioblastoma cells are still unknown. In this study, we use cellular methodological experiments including cell counting kit-8 (CCK-8) assay, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining assay, flow cytometry assay, transmission electron microscopy (TEM) and Western blot. The results show that N45 significantly suppresses the proliferation of glioblastoma cells and TMZ-resistant glioblastoma cells (U87R) by inducing mitochondrial apoptosis through reactive oxygen species (ROS)/phosphoinositide 3-kinase (PI3K)/Akt signal pathway, and the N-acetyl-L-cysteine (NAC) combined with N45 effectively reduced N45-mediated apoptosis and reversed the inhibition of PI3K/Akt signal pathway. In addition, N45 decreased the drug-resistance by down-regulation of nuclear factor kappa-B p65 (NF-κB p65) to attenuate O6-methylguanine-DNA methyltransferase (MGMT) in TMZ-resistant glioblastoma cells (U87R). Our findings proved that N45 might be a potential therapeutic agent against glioblastoma and TMZ-resistant glioblastoma, promising to be a potential agent to reduce drug resistance.