PLK1 Knockdown Inhibits Cell Proliferation and Cell Apoptosis, and PLK1 Is Negatively Regulated by miR-4779 in Osteosarcoma Cells

Polo-like kinase 1 (PLK1) is a ubiquitous serine/threonine protein kinase. It is reported to be involved in the occurrence and progression of various human cancers. In the present study, we explored the role and molecular mechanism of PLK1 in the proliferation of osteosarcoma (OS) cells. We found that PLK1 expression was higher in MG63/Dox cells than in MG63 cells, while inhibiting or interfering with the level of PLK1 suppressed cell proliferation of MG63/Dox cells. TargetScan analysis predicted that miR-4779 would interact with the 3'-UTR of PLK1 mRNAs and also inhibit cell autophagy of MG63/Dox cells. The data demonstrated that miR-4779 negatively regulates the expression of PLK1, and both miR-4779 and PLK1 regulate cell proliferation and cell apoptosis of MG63/Dox cells, processes that are involved in the drug resistance of OS cells.

Ginkgolide B inhibits hydrogen peroxide‑induced apoptosis and attenuates cytotoxicity via activating the PI3K/Akt/mTOR signaling pathway in H9c2 cells

Ginkgolide B (GB) is a diterpene lactone found in the leaves of the traditional Chinese medicinal plant Ginkgo that has been shown to have various pharmacological effects. However, the anti-apoptotic properties of GB in cardiovascular disease remain poorly understood. The present study aimed to investigate the effect of GB on hydrogen peroxide-induced cell injury in cardiac H9c2 cells, and to further clarify its protective mechanism of action. An in vitro hydrogen peroxide-treated H9c2 cell model was used in order to mimic myocardial ischemia-reperfusion (I/R) injury. Cell viability was assessed by the Cell Counting Kit-8 assay. The induction of apoptosis was determined by flow cytometry and staining was performed using Hoechst 33342. In addition, the effect of GB on the expression levels of apoptosis-associated proteins was evaluated by western blot analysis. The present study demonstrated that GB protected against hydrogen peroxide-induced cytotoxicity and cell apoptosis in H9c2 cardiac cells. GB upregulated the expression level of the anti-apoptotic protein Bcl-2 and downregulated the expression levels of the pro-apoptotic proteins cleaved caspase-3 and Bax in hydrogen peroxide-treated H9c2 cells. The molecular mechanism underlying the anti-apoptotic effects of GB was subsequently detected. GB pretreatment activated the PI3K/Akt/mTOR signaling pathway and caused an increase in the phosphorylation levels of Akt and mTOR in hydrogen peroxide-treated H9c2 cells. These results revealed that GB inhibited hydrogen peroxide-induced apoptosis in H9c2 cells via activation of the PI3K/Akt/mTOR signaling pathway. These findings indicate the potential therapeutic benefits of GB in the treatment of myocardial I/R injury.

Magnetic Measurement and Stimulation of Cellular and Intracellular Structures

From single-pole magnetic tweezers to robotic magnetic-field generation systems, the development of magnetic micromanipulation systems, using electromagnets or permanent magnets, has enabled a multitude of applications for cellular and intracellular measurement and stimulation. Controlled by different configurations of magnetic-field generation systems, magnetic particles have been actuated by an external magnetic field to exert forces/torques and perform mechanical measurements on the cell membrane, cytoplasm, cytoskeleton, nucleus, intracellular motors, etc. The particles have also been controlled to generate aggregations to trigger cell signaling pathways and produce heat to cause cancer cell apoptosis for hyperthermia treatment. Magnetic micromanipulation has become an important tool in the repertoire of toolsets for cell measurement and stimulation and will continue to be used widely for further explorations of cellular/intracellular structures and their functions. Existing review papers in the literature focus on fabrication and position control of magnetic particles/structures (often termed micronanorobots) and the synthesis and functionalization of magnetic particles. Differently, this paper reviews the principles and systems of magnetic micromanipulation specifically for cellular and intracellular measurement and stimulation. Discoveries enabled by magnetic measurement and stimulation of cellular and intracellular structures are also summarized. This paper ends with discussions on future opportunities and challenges of magnetic micromanipulation in the exploration of cellular biophysics, mechanotransduction, and disease therapeutics.

Lidocaine improves cerebral ischemia-reperfusion injury in rats through cAMP/PKA signaling pathway

Influence of lidocaine on rats with cerebral ischemia-reperfusion injury (CIRI) was studied to explore its mechanism of action. A total of 30 Sprague-Dawley rats were randomly divided into control group and model group, and the rat model of CIRI was prepared by the suture-occluded method in the model group. Then the rats in the model group were randomly assigned into the model group (n=10) and the lidocaine group (n=10). The neurological function score of rats was evaluated, and the levels of serum B-cell lymphoma-2 (Bcl-2) and Bcl-2 associated X protein (Bax) in rats were determined using ELISA. TUNEL assay was performed to detect the neuronal apoptosis in the brain of rats. The messenger ribonucleic acid (mRNA) and protein expression levels of cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) were measured via RT-PCR and western blotting, respectively. Compared with those in the control group, the rats in the model group had an elevated neurological function score, a raised level of Bcl-2, but a reduced level of Bax in the serum, an obviously increased rate of neuronal apoptosis in the brain and decreased mRNA and protein levels of cAMP and PKA in cerebral tissues. The rats in lidocaine group had a lower neurological function score, a lower level of Bcl-2, but a higher level of Bax in the serum, an evidently lower rate of neuronal apoptosis in the brain and higher mRNA and protein levels of cAMP and PKA in cerebral tissues than those in the model group. Lidocaine can improve the neurological function of rats with CIRI and inhibit neuronal apoptosis in the brain, and its mechanism of action may be related to the activation of the cAMP/PKA signaling pathway.

Enhanced anti-tumor efficacy of 5-aminolevulinic acid-gold nanoparticles-mediated photodynamic therapy in cutaneous squamous cell carcinoma cells

The objective of this study was to investigate whether the conjugation of gold nanoparticles (GNPs) to 5-aminolevulinic acid (5-ALA) could enhance the anti-tumor efficiency of photodynamic therapy (PDT) in epidermoid carcinoma cells. The mRNA and protein expression levels were determined by quantitative real-time PCR and western blot, respectively. Cell viability, apoptosis, invasion, and migration were determined by MTT assay, flow cytometry, transwell invasion assay, and migration assay, respectively. Singlet oxygen generation was detected by the singlet oxygen sensor green reagent assay. Our results showed that PDT with 5-ALA and GNPs-conjugated 5-ALA (5-ALA-GNPs) significantly suppressed cell viability, increased cell apoptosis and singlet oxygen generation in both HaCat and A431 cells, and PDT with 5-ALA and 5-ALA-GNPs had more profound effects in A431 cells than that in HaCat cells. More importantly, 5-ALA-GNPs treatment potentiated the effects of PDT on cell viability, cell apoptosis, and singlet oxygen generation in A431 cells compared to 5-ALA treatment. Further in vitro assays showed that PDT with 5-ALA-GNPs significantly decreased expression of STAT3 and Bcl-2 and increased expression of Bax in A431 cells compared with PDT with 5-ALA. In addition, 5-ALA-GNPs treatment enhanced the inhibitory effects of PDT on cell invasion and migration and Wnt/β-catenin signaling activities in A431 cells compared to 5-ALA treatment. In conclusion, our results suggested that GNPs conjugated to 5-ALA significantly enhanced the anti-tumor efficacy of PDT in A431 cells, which may represent a better strategy to improve the outcomes of patients with cutaneous squamous cell carcinoma.

Chrysin Induced Cell Apoptosis and Inhibited Invasion Through Regulation of TET1 Expression in Gastric Cancer Cells

Objective

Ten-eleven translocation (TET) enzymes that oxidize a 5-methylcytosine (5mC) to yield 5-hydroxymethylcytosine (5hmC) have been responsible for fine-tuning methylation patterns and exhibit role in epigenetic modifications. Chrysin, a natural flavone frequently present in honey, has been recognized to exhibit anti-tumor properties. In this study, we investigated the effects of Chrysin in the expression pattern of TET proteins in gastric cancer (GC) cells.

Materials and Methods

Using qRT-PCR and Western blot analysis, we analyzed the expression of TET1 in GC cells in vitro following treatment with Chrysin. Immunofluorescence staining detected the expression levels of 5mC and 5hmC. Flow cytometry, wound healing, and Matrigel invasion assays were performed to determine cell proliferation, cell cycle, apoptosis, and migration and invasion of GC cells following treatment with Chrysin, si-TET1, and TET1-KO. Furthermore, a xenograft model was developed to analyze the expression pattern of TET1 on tumor development in vivo.

Results

qRT-PCR and Western blot assays indicated that treatment with Chrysin significantly promoted the expression of TET1 in GC cells. Immunofluorescence study further confirmed that TET1 and 5hmC levels were significantly enhanced following treatment with Chrysin in MKN45 cells. Moreover, our results suggested that Chrysin could noticeably induce cell apoptosis and inhibit cell migration and invasion. Further, knockdown and overexpression of TET1 were conducted to investigate whether TET1 expression affected cell apoptosis, and cell migration and invasion in MKN45 cells. The results indicated that overexpression of TET1 markedly promoted cell apoptosis and inhibited cell migration and invasion. Furthermore, the TET1 gene knocked out was generated using the CRISPR/Cas9 system. Our data suggested that TET1 expression was associated with GC tumor growth in vivo.

Conclusion

This study indicated that Chrysin exerted anti-tumor effects through the regulation of TET1 expression in GC and presented TET1 as a novel promising therapeutic target for GC therapy.

Identification of UAP1L1 as tumor promotor in gastric cancer through regulation of CDK6

Gastric cancer (GC) is one of the most commonly diagnosed malignancies in digestive tract and its underlying molecular mechanism is still not clear, so we aimed to reveal the relationship between GC and UDP-GlcNAc pyrophosphorylase-1 like 1 (UAP1L1). The detection of UAP1L1 expression in GC tumor and normal tissues was accomplished by immunohistochemistry and demonstrated the upregulation of UAP1L1 in GC, which was statistically associated with tumor grade. GC cell models constructed via transfection of UAP1L1-silencing/overexpressing lentiviruses were employed for evaluating the effects of UAP1L1 knockdown/overexpression on GC in vitro and in vivo. The results indicated that UAP1L1 played important role in development of GC through regulating cell proliferation, colony formation, cell apoptosis and cell migration. Subsequently, CDK6 was identified as a potential target in UAP1L1 induced regulation of GC, downregulation of which exhibited similar inhibition effects on GC with UAP1L1. Moreover, it was demonstrated that the promotion of GC by UAP1L1 overexpression could be significantly attenuated or even reversed by simultaneously silencing CDK6. In conclusion, UAP1L1 was reported to be a tumor promotor in the development and progression of GC which may exert its role through regulating CDK6 and may act as a candidate of therapeutic target in treatment.

[Study on protective effect of water extract from Sabia parviflora on liver injury in mice induced by acetaminophen]

The aim of this study was to observe the protective effect of water extract from Sabia parviflora on mice with acute liver injury induced by acetaminophen, and investigate its possible mechanism. Fifty-eight Kunming mice were divided into 6 groups, 8 in the normal group, 10 in the model group, 10 in the biphenyl diester group, and 10 each in the low, medium and high dose groups. After adaptive feeding for one week, the mice in normal group were intragastrically administered with an equal volume of 0.5% sodium carboxymethylcellulose sodium(CMC-Na), and the mice in other groups were intragastrically administered with corresponding drugs at 20 mL·kg~(-1) once a day. Then acetaminophen(200 mg·kg~(-1)) was administered after the above drug administration except the normal group. The behavior and signs of the experimental animals were observed every day and the samples were taken for experiments on the next day of the final administration. The liver mass and mass index were calculated. The blood was collected from the abdominal aorta and centrifuged to obtain the serum for detecting aspartate aminotransferase(AST) activity and alanine aminotransferase(ALT) activity. The liver tissue homogenate was used to detect superoxide dismutase(SOD) activity, glutathione(glutathione, r-glutamyl cysteingl+glycine, GSH) activity and malondialdehyde(MDA) content. Liver tissue was analyzed for histological analysis. The results showed that S. parviflora could alleviate the lipid peroxidation damage in the liver caused by acetaminophen, reduce the ALT and AST activities in serum, increase the levels of SOD and GSH in liver tissue, decrease the content of MDA in liver tissue, and inhibit the apoptosis. S. parviflora could also improve the live histopathological profile, protect liver cells and restore liver function. Among them, the high dose had the most significant effect and showed dose-effect relationship. This study indicated that S. parviflora had a significant protective effect on acetaminophen-induced liver injury in mice, and its mechanism may be related to its anti-oxidation effect and inhi-bitory effect on apoptosis.

Underlying mechanisms of apoptosis in HepG2 cells induced by polyphyllin I through Fas death and mitochondrial pathways

Aims: Polyphyllin I, a steroidal saponin in Rhizoma paridis, which possess broad application prospects in cancer prevention and treatment. The purpose of this study was to determine the potential cytotoxicity and mechanism of Polyphyllin I in HepG2 cells.Main methods: In this study, we used MTT to evaluate cell survival. Cell apoptosis rate, cell cycle distribution, mitochondrial membrane potential and ros levels were measured by flow cytometry, and the expression of apoptosis-related proteins was determined by Western blot analysis.Key findings: Polyphyllin I significantly reduced cell viability and induced HepG2 cell apoptosis in a dose and time-dependent manner. Compared with the control group, it could induce reactive oxygen species (ROS) generation and depolarization of matrix metalloproteinases in liver cells. Polyphyllin I dose-dependent increased the release of mitochondrial cytochrome c, and levels of Fas, p53, p21, and Bax/Bcl-2 ratios, as well as the activation of cleaved caspase-3, -8, -9, and subsequent cleavage of the poly (ADP-ribose) polymerase (PARP). The G2/M phase cell cycle arrest was induced by increasing the expression of p21 and cyclin E1, and significantly reducing the expression of cyclin A2 and CDK2.Significance: Our results suggested that Polyphylin I inhibited cell proliferation and growth by triggering G2/M cell cycle arrest, and induced apoptosis through intracellular and extracellular apoptosis pathways to cause cell death by generating reactive oxygen species.

IQ motif-containing GTPase-activating protein 1 is essential for the optimal maintenance of lung ILC2s

Group 2 innate lymphoid cells (ILC2s) play critical roles in type 2 immunity and are crucial for pathogenesis of various types of inflammatory disease. IQ motif-containing GTPase-activating protein 1 (IQGAP1) is a ubiquitously expressed scaffold protein that is involved in multiple cellular functions such as cell survival and trafficking. While the roles for IQGAP1 in T and B lymphocytes have been uncovered, the physiological significance of IQGAP1 in innate lymphocytes remains to be elucidated. In the current study, we demonstrate that using bone marrow chimeras, the deficiency of IQGAP1 caused an impaired survival of lung ILC2s in a cell-intrinsic manner and that Iqgap1-/- mice displayed decreased accumulation of ILC2s after administration of papain and thereby reduced the pathology of the disease. Moreover, Iqgap1-/- ILC2s showed a significantly enhanced apoptosis as compared to wild-type ILC2s under both steady-state and inflammatory conditions. Together these results identify for the first time that IQGAP1 is essential for homeostasis of ILC2s in the lung.

Downregulation of LncRNA NORAD promotes Ox-LDL-induced vascular endothelial cell injury and atherosclerosis

Long noncoding RNAs (lncRNAs) play important roles in the development of vascular diseases. However, the effect of lncRNA NORAD on atherosclerosis remains unknown. This study aimed to investigate the effect NORAD on endothelial cell injury and atherosclerosis. Ox-LDL-treated human umbilical vein endothelial cells (HUVECs) and high-fat-diet (HFD)-fed ApoE^−/− mice were used as in vitro and in vivo models. Results showed that NORAD-knockdown induced cell cycle arrest in G0/G1 phase, aggravated ox-LDL-induced cell viability reduction, cell apoptosis, and cell senescence along with the increased expression of Bax, P53, P21 and cleaved caspase-3 and the decreased expression of Bcl-2. The effect of NORAD on cell viability was further verified via NORAD-overexpression. NORAD- knockdown increased ox-LDL-induced reactive oxygen species, malondialdehyde, p-IKBα expression levels and NF-κB nuclear translocation. Proinflammatory molecules ICAM, VCAM, and IL-8 were also increased by NORAD- knockdown. Additionally, we identified the strong interaction of NORAD and IL-8 transcription repressor SFPQ in HUVECs. In ApoE^−/− mice, NORAD-knockdown increased the lipid disorder and atherosclerotic lesions. The results have suggested that lncRNA NORAD attenuates endothelial cell senescence, endothelial cell apoptosis, and atherosclerosis via NF-κB and p53–p21 signaling pathways and IL-8, in which NORAD-mediated effect on IL-8 might through the direct interaction with SFPQ.

miR-107 inhibited malignant biological behavior of non-small cell lung cancer cells by regulating the STK33/ERK signaling pathway in vivo and vitro

Background

The role of miRNAs in non-small cell lung cancer (NSCLC) has been broadly studied and confirmed, and miR-107 has attracted an ever-growing level of attention. This study set out to research the mechanism of the effect of miR-107 on the malignant biological behavior of NSCLC in vivo and vitro.

Methods

The expression of miRNAs related to the development of NSCLC was detected by RT-qPCR. Western blotting was carried out to detect expression levels of serine/threonine kinase 33 (STK33) and proteins related to the extracellular regulated protein kinases (ERK) signaling pathway, while cell proliferation was detected using cell counting kit-8 (CCK-8). The cell apoptosis rate was measured using flow cytometry. The invasion ability was detected by Transwell assay. In vivo tumor growth assays were performed on mice. The expression ERK signaling pathway-related proteins in vivo was evaluated by immunohistochemistry staining. The targeted relationship between miR-107 and STK33 was confirmed by the dual luciferase reporter gene.

Results

In NSCLC cell lines and tissues, miR-107 was downregulated. Overexpression of miR-107 inhibited malignant biological behavior of NSCLC cell lines, and suppressed tumor growth in vivo. In addition, STK33 is one of the target genes of miR-107. Therefore, miR-107 suppressed cell proliferation and invasion and promoted tumor growth in vivo and cell apoptosis of NSCLC in vitro. The mechanism was found to be miR-107 targeting STK33, and a lack of STK33 led to the activation of ERK signaling pathway.

Conclusions

miR-107 inhibited malignant biological behavior of NSCLC through regulation of the STK33/ERK signaling pathway.

Anti-apoptosis effect of heme oxygenase-1 on lung injury after cardiopulmonary bypass

Background

This study aimed to investigate the anti-apoptosis effects of heme oxygenase-1 (HO-1) on lung injury (LI) after cardiopulmonary bypass (CPB) and its probable mechanisms.

Methods

One hundred and forty-four male Wistar rats were divided into 3 groups randomly: group A (control group), group B (cobalt protoporphyrin, CoPP), and group C [CoPP plus zinc protoporphyrin (ZnPP)]. Lung tissues were harvested at different time: before CPB (T0), 0 min after CPB (T1), 2 h after CPB (T2), 6 h (T3), 12 h (T4), and 24 h (T5).

Results

The HO-1 protein expressions in lung tissue in group B were higher than those in group A and group C in any given time, and the same as HO-1 activity (P<0.05). The expressions of Bcl-2 protein in group B at all time point after bypass were higher than those in group A and group C, and the difference was statistically significant (P<0.05). Apoptosis index (AI) in group B at any time point after bypass were lower than those in group A and group C (P<0.05).

Conclusions

CoPP can significantly increase the expression of HO-1 protein in lung tissue. HO-1 is still highly expressed after CPB, so as to play an important part in anti-apoptosis, and reduce LI.

[Effect of Hematopoietic Pre-B-cell Leukemia Transcription Factor Interacting Protein Knockdown on Proliferation,Cell Cycle and Apoptosis in Pancreatic Cancer Cells]

Objective To unravel the role of hematopoietic pre-B-cell leukemia transcription factor interacting protein(HPIP)in the proliferation,cell cycle,and apoptosis of pancreatic ductal adenocarcinoma(PDAC)cells. Methods The HPIP expression in PDAC tissue was determined by immunohistochemical staining.Knockdown of HPIP was accomplished in MIA PaCa-2 and BxPC-3 cell lines by transient transfection of HPIP siRNA and validated by Western blotting.Cell proliferation was assessed using the cell counting kit-8 assay and colony formation assay.Cell cycle and apoptosis were detected by flow cytometry.Western blotting was performed to detect the expression levels of cyclin D1,caspase 7,and cleaved caspase 7. Results HPIP was overexpressed in PDAC tissue compared with matched adjacent pancreatic tissue(Z=-2.060,P=0.039).Knockdown of HPIP inhibited the proliferation of MIA PaCa-2 and BxPC-3 cells(all P<0.05).Knockdown of HPIP significantly reduced the positive colonies formed by MIA PaCa-2 and BxPC-3 cells(t=4.706,P=0.009;t=9.514,P=0.000).Knockdown of HPIP decreased the proportion of S phase cells(t=7.642,P=0.001;t=2.714,P=0.051)and increased the proportion of G₀/G₁ phase cells(t=3.244,P=0.031;t=6.095,P=0.003)in MIA PaCa-2 and BxPC-3 cells.Meanwhile,knockdown of HPIP increased the proportions of late-phase MIA PaCa-2 and BxPC-3 cells(t=24.58,P=0.000;t=36.45,P=0.000)and the overall apoptosis rate(t=29.43,P=0.000;t=43.52,P=0.000).In MIA PaCa-2 and BxPC-3 cells,knockdown of HPIP decreased the expression level of cyclin D1(t=6.705,P=0.002;t=6.238,P=0.003)and increased the expression level of cleaved caspase 7(t=3.991,P=0.016;t=6.536,P=0.002). Conclusions HPIP is overexpressed in PDAC tissue.Knockdown of HPIP inhibits the proliferation and G₀/G₁ to S transition of PDAC cells.Meanwhile,knockdown of HPIP promotes the apoptosis of PDAC cells.Thus,HPIP may act as an oncogene in PDAC.

Geniposide inhibits glucolipotoxicity and cooperates with Txnip knockdown to potentiate cell adaption to endoplasmic reticulum stress in pancreatic beta cells

Thioredoxin-interacting protein (Txnip), a negative regulator of thioredoxin, has become an attractive therapeutic target to alleviate metabolic diseases. Our previous data demonstrated that geniposide improved glucose-stimulated insulin secretion by accelerating Txnip degradation and prevented the early-stage apoptosis of pancreatic β cells induced by palmitate, but the underlying mechanisms are still unclear. The objective of this study is to identify the role of Txnip in geniposide preventing the apoptosis of pancreatic β cells induced by high glucose and palmitate (HG/PA). The results revealed that geniposide attenuated HG/PA-induced cell apoptosis and the expression of Bax and caspase-3, while increasing mitochondrial membrane potential and the anti-apoptotic protein levels of heme-oxygenase-1 (HO-1) and Bcl-2 in INS-1 rat pancreatic β cells. Knockdown of the Txnip gene raised the levels of anti-apoptotic proteins HO-1 and Bcl-2 and geniposide potentiated the effect of Txnip when the INS-1 cells were challenged by HG/PA. Furthermore, geniposide enhanced the adoptive unfolded protein response by increasing the phosphorylation of PERK/eIF2α and IRE1α in HG/PA-treated INS-1 cells. The results together suggest that geniposide might be useful to antagonize glucolipotoxicity and Txnip might be a pleiotropic cellular factor in pancreatic β cells.

The therapeutic value of the SphK1-targeting microRNA-3677 in human osteosarcoma cells

Sphingosine kinase 1 (SphK1) is a potential therapeutic target for human osteosarcoma (OS). SphK1-targeting microRNAs (miRNAs) could have important therapeutic value for OS. We discovered that micorRNA-3677 (miR-3677) is a SphK1-targeting miRNA, inhibiting OS cell progression. The results of RNA-Pull down assay confirmed direct binding between biotinylated-miR-3677 and SphK1 mRNA in primary human OS cells. In established and primary human OS cells forced overexpression of miR-3677, by a lentiviral construct, decreased SphK1 3’-UTR (untranslated region) activity and downregulated SphK1 expression. Both were however enhanced with miR-3677 inhibition in OS cells. Function studies demonstrated that OS cell growth, proliferation and migration were inhibited with miR-3677 overexpression, but augmented with miR-3677 inhibition. MiR-3677 overexpression-induced anti-OS cell activity was reversed with re-expression of the 3’-UTR-depleted SphK1. Additionally, in SphK1 knockout OS cells (by CRISPR/Cas9 strategy), altering miR-3677 expression failed to further alter cell functions. Finally, we show that miR-3677 expression was significantly downregulated in primary human OS tissues, correlating with SphK1 mRNA upregulation. We conclude that targeting SphK1 by miR-3677 inhibits human OS cell progression.

The combination of artesunate and carboplatin exerts a synergistic anti-tumour effect on non-small cell lung cancer

Carboplatin (CBP) is a widely used targeted anticancer therapeutic drug; however, multi-drug resistance induced by the accumulation of CBP eventually causes diseases progression. The anti-malarial drug artesunate (ART) also exerts anticancer effects in various cancers; however, the combined effect of ART and CBP on non-small cell lung cancer (NSCLC) remains unclear. In the present study, the NSCLC cell line A549 was pretreated with various concentrations of CBP, ART and gemcitabine (GEM). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were conducted to detect cell viability. Cell apoptosis was evaluated by both flow cytometry and TUNEL apoptotic assay. The expression profiles of cell cycle-related proteins and apoptotic proteins were determined by western blot. Cell clone numbers were visualized using crystal violet staining. Here, we found that both CBP and ART suppressed cell viability, and promoted cell apoptosis, and the combined application of ART and CBP at a lower concentration exhibited synergistic effects. Specifically, the combination of ART and CBP at a lower concentration suppressed cell clone numbers, promoted cell cycle arrest at the G₂ /M phase, and induced the expression of the cell cycle and apoptosis-related proteins BAX, p21, p53, and Caspase-3, while decreasing Bcl-2 and Cyclin B1 expression. Based on these results, we concluded that combined application of ART and CBP exerts synergistic anti-tumour effects on NSCLC by enhancing cell apoptosis in a mitochondria-dependent manner.

Gluconokinase IDNK Promotes Cell Proliferation and Inhibits Apoptosis in Hepatocellular Carcinoma

Purpose

Hepatocellular carcinoma (HCC) is one of the deadliest cancers globally with a poor prognosis. Breakthroughs in the treatment of HCC are urgently needed. This study explored the role of IDNK in the development and progression of HCC.

Methods

IDNK expression was suppressed using short hairpin (shRNA) in BEL-7404 and Huh-7 cells. The expression of IDNK in HCC cells after IDNK knockdown was evaluated by real-time quantitative RT-PCR analysis and Western blot. After IDNK silencing, the proliferation and apoptosis of HCC cells were evaluated by Celigo cell counting, flow cytometry analysis, MTT assay, and caspase3/7 assay. Gene expressions in BEL-7404 cells transfected with IDNK shRNA lentivirus plasmid and blank control plasmid were evaluated by microarray analysis. The differentially expressed genes induced by deregulation of IDNKwere identified, followed by pathway analysis.

Results

The expression of IDNK at the mRNA and protein levels was considerably reduced in shRNA IDNK transfected cells. Knockdown of IDNK significantly inhibited HCC cell proliferation and increased cell apoptosis. A total of 1196 genes (585 upregulated and 611 downregulated) were differentially expressed in IDNK knockdown BEL-7404 cells. The pathway of tRNA charging with Z-score = -3 was significantly inhibited in BEL-7404 cells with IDNK knockdown.

Conclusion

IDNK plays a key role in the proliferation and apoptosis of HCC cells. IDNK may be a candidate therapeutic target for HCC.

The Association of Neuronal Stress with Activating Transcription Factor 3 in Dorsal Root Ganglion of in vivo and in vitro Models of Bortezomib- Induced Neuropathy

BACKGROUND

The notion that proteasome inhibitor bortezomib (BTZ) induced intracellular oxidative stress resulting in peripheral neuropathy has been generally accepted. The association of mitochondrial dysfunction, cell apoptosis, and endoplasmic reticulum (ER) stress with intracellular oxidative stress is ambiguous and still needs to be investigated. The activation of activating transcription factor 3 (ATF3) is a stress-hub gene which was upregulated in dorsal root ganglion (DRG) neurons after different kinds of peripheral nerve injuries.

OBJECTIVE

To investigate a mechanism underlying the action of BTZ-induced intracellular oxidative stress, mitochondrial dysfunction, cell apoptosis, and ER stress via activation of ATF3.

METHODS

Primary cultured DRG neurons with BTZ induced neurotoxicity and DRG from BTZ induced painful peripheral neuropathic rats were used to approach these questions.

RESULTS

BTZ administration caused the upregulation of ATF3 paralleled with intracellular oxidative stress, mitochondrial dysfunction, cell apoptosis, and ER stress in DRG neurons both in vitro and in vivo. Blocking ATF3 signaling by small interfering RNA (siRNA) gene silencing technology resulted in decreased intracellular oxidative stress, mitochondrial dysfunction, cell apoptosis, and ER stress in DRG neurons after BTZ treatment.

CONCLUSION

This study exhibited important mechanistic insight into how BTZ induces neurotoxicity through the activation of ATF3 resulting in intracellular oxidative stress, mitochondrial dysfunction, cell apoptosis, and ER stress and provided a novel potential therapeutic target by blocking ATF3 signaling.

Protective effects of fisetin against myocardial ischemia/reperfusion injury

The underlying mechanism of the myocardial protective effect of fisetin was studied in a rat ischemia/reperfusion injury model. Sprague-Dawley rats were randomly assigned to seven groups and pretreated with different solutions by gavage administration. A rat model of cardiac ischemia/reperfusion injury was established. Plasma levels of Von Willebrand factor (vWF) were determined by ELISA, flow cytometry was used to determine the level of cardiomyocyte apoptosis and 2,3,5-triphenyltetrazolium staining was used to determine the size of myocardial infarcts. Hematoxylin and eosin-stained sections of myocardial tissues were examined for pathological changes. Expressions of nuclear factor (NF)-κB and matrix metallopeptidase 9 (MMP-9) were measured by immunohistochemistry. Compared with the model group, rats pretreated with fisetin, quercetin and aspirin showed significant prolongation of clotting time, prothrombin time, thrombin time and activated partial thromboplastin time. Fisetin treatment better maintained the integrity of myocardial fibers and nuclear integrity, reduced the percentage of apoptotic myocardial cells, inhibited expression of NF-κB, decreased the loss of MMP-9 and reduced nuclear translocation of NF-kB. Rats pretreated with fisetin also demonstrated a significant decrease in plasma levels of vWF. In addition, the protective effect of fisetin on myocardial cells was found to be dose dependent.

MDM2-Associated Clusterization-Triggered Emission and Apoptosis Induction Effectuated by a Theranostic Spiropolymer

Heteroatom-containing spiropolymers were constructed in a facile manner by a catalyst-free multicomponent spiropolymerization route. P1a2b as the most potent of these spiropolymers, demonstrates cluster-triggered emission resulting from strong interactions with the MDM2 protein. By preventing the anti-apoptotic p53/MDM2 interaction, P1a2b triggers apoptosis in cancerous cells, while demonstrating a good biocompatibility and non-toxicity in non-cancerous cells. The combined results from solution and cell-based cluster-triggered emission studies, docking, protein expression experiments and cytotoxicity data strongly support the MDM2-binding hypothesis and indicate a potential application as a fluorescent cancer marker as well as therapeutic for this spiropolymer.

The Yin and Yang of Autosomal Recessive Primary Microcephaly Genes: Insights from Neurogenesis and Carcinogenesis

The stem cells of neurogenesis and carcinogenesis share many properties, including proliferative rate, an extensive replicative potential, the potential to generate different cell types of a given tissue, and an ability to independently migrate to a damaged area. This is also evidenced by the common molecular principles regulating key processes associated with cell division and apoptosis. Autosomal recessive primary microcephaly (MCPH) is a neurogenic mitotic disorder that is characterized by decreased brain size and mental retardation. Until now, a total of 25 genes have been identified that are known to be associated with MCPH. The inactivation (yin) of most MCPH genes leads to neurogenesis defects, while the upregulation (yang) of some MCPH genes is associated with different kinds of carcinogenesis. Here, we try to summarize the roles of MCPH genes in these two diseases and explore the underlying mechanisms, which will help us to explore new, attractive approaches to targeting tumor cells that are resistant to the current therapies.

C1q/TNF-related protein 6 (CTRP6) attenuates renal ischaemia-reperfusion injury through the activation of PI3K/Akt signalling pathway

C1q/TNF-related protein 6 (CTRP6) is a member of the CTRP family that has been reported to exhibit a nephroprotective effect. However, the role of CTRP6 in renal ischaemia/reperfusion (I/R) injury (IRI) remains unclear. In the present study, we aimed to explore the protective effect of CTRP6 in renal IRI and the potential mechanism. We found that CTRP6 expression was markedly decreased in the kidneys of mice subjected to I/R and HK-2 cells in response to hypoxia/reoxygenation (H/R) stimulation. Recombinant CTRP6 protein protected against renal I/R injury by the reduction of blood urea nitrogen (BUN) and creatinine levels. The increased production of ROS and malondialdehyde (MDA), as well the decreased activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) caused by H/R induction were mitigated by CTRP6 in HK-2 cells. The caspase-3 activity and apoptotic rate were both decreased in CTRP6-overexpressing HK-2 cells. In addition, we also found that knockdown of CTRP6 aggravated H/R-caused oxidative stress and cell apoptosis in HK-2 cells. Moreover, CTRP6 overexpression enhanced the H/R-stimulated activation of PI3K/Akt pathway in HK-2 cells. Inhibition of PI3K reversed the nephroprotective effects of CTRP6 in HK-2 cells. Taken together, CTRP6 exerted protective effects against H/R-caused oxidative injury in HK-2 cells via activating the PI3K/Akt pathway.

Antitumor Effect of miR-1294/Pyruvate Kinase M2 Signaling Cascade in Osteosarcoma Cells

Background

MicroRNAs (miRNAs) can act as negative regulators of gene expression, and play a crucial role in cancer progression. The aim of this study was to investigate the role of miR-1294/pyruvate kinase M2 (PKM2) axis in osteosarcoma cells in vitro and in vivo.

Methods

The function of miR-1294 and its association with PKM2 in osteosarcoma cells were studied by real-time PCR, CCK-8, Western blot, scratch test, transwell assay, flow cytometry, and dual-luciferase reporter assays. The effect of miR-1294 on tumor growth in vivo was evaluated in a subcutaneous xenograft model of osteosarcoma.

Results

miR-1294 was downregulated in osteosarcoma cells. Forced overexpression of miR-1294 inhibited cell proliferation, migration, and invasion, and induced G0/G1 arrest and apoptosis. Consistently, protein expression levels of proliferating cell nuclear antigen, c-Myc, cyclin D1, active matrix metalloproteinase 2, and active matrix metalloproteinase 9 were decreased, and cleaved caspase 3 and cleaved PARP were increased following miR-1294 overexpression. Moreover, we demonstrated that PKM2 was a target of miR-1294 in osteosarcoma cells, and the effects caused by miR-1294 mimic were reversed by the overexpression of PKM2. Furthermore, we found that upregulation of miR-1294 inhibited tumorigenesis of osteosarcoma cells in vivo, which was accompanied by downregulation of PKM2.

Conclusion

Our results revealed that miR-1294/PKM2 signaling cascade exerts important roles in the regulation of tumor progression, implying that this pathway may serve as a potential therapeutic target in osteosarcoma.

The Effects of Mobile Phone Radiofrequency Radiation on Cochlear Stria Marginal Cells in Sprague-Dawley Rats

To investigate the possible mechanisms for biological effects of 1,800 MHz mobile radiofrequency radiation (RFR), the radiation-specific absorption rate was applied at 2 and 4 W/kg, and the exposure mode was 5 min on and 10 min off (conversation mode). Exposure time was 24 h short-term exposure. Following exposure, to detect cell DNA damage, cell apoptosis, and reactive oxygen species (ROS) generation, the Comet assay test, flow cytometry, DAPI (4',6-diamidino-2-phenylindole dihydrochloride) staining, and a fluorescent probe were used, respectively. Our experiments revealed that mobile phone RFR did not cause DNA damage in marginal cells, and the rate of cell apoptosis did not increase (P > 0.05). However, the production of ROS in the 4 W/kg exposure group was greater than that in the control group (P < 0.05). In conclusion, these results suggest that mobile phone energy was insufficient to cause cell DNA damage and cell apoptosis following short-term exposure, but the cumulative effect of mobile phone radiation still requires further confirmation. Activation of the ROS system plays a significant role in the biological effects of RFR. Bioelectromagnetics. © 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc.