Magnolol induces apoptosis in osteosarcoma cells via G0/G1 phase arrest and p53-mediated mitochondrial pathway

Diosgenin potentiates the anticancer effect of doxorubicin and volasertib via regulating polo-like kinase 1 and triggering apoptosis in hepatocellular carcinoma cells

A common approach to cancer therapy is the combination of a natural product with chemotherapy to overcome sustained cell proliferation and chemotherapy resistance obstacles. Diosgenin (DG) is a phytosteroidal saponin that is naturally present in a vast number of plants and has been shown to exert anti-cancer activities against several tumor cells. Herein, we assessed the chemo-modulatory effects of DG on volasertib (Vola) as a polo-like kinase 1 (PLK1) inhibitor and doxorubicin (DOX) in hepatocellular carcinoma (HCC) cell lines. DOX and Vola were applied to two human HCC cell lines (HepG2 and Huh-7) alone or in combination with DG. The cell viability was determined, and gene expressions of PLK1, PCNA, P53, caspase-3, and PARP1 were evaluated by RT-qPCR. Moreover, apoptosis induction was determined by measuring active caspase-3 level using ELISA method. DG enhanced the anticancer effects of Vola and DOX. Moreover, DG enhanced Vola- and DOX-induced cell death by downregulating the expressions of PLK1 and PCNA, elevating the expressions of P53 and active caspase-3. DG showed promising chemo-modulatory effects to Vola and DOX against HCC that may be attributed partly to the downregulation of PLK1 and PCNA, upregulation of tumor suppressor protein P53, and apoptosis induction. Thus, DG combination with chemotherapy may be a promising treatment approach for HCC.

Amicis Omnia Sunt Communia: NF-κB Inhibition as an Alternative to Overcome Osteosarcoma Heterogeneity

Tumor heterogeneity poses a significant challenge in osteosarcoma (OS) treatment. In this regard, the "omics" era has constantly expanded our understanding of biomarkers and altered signaling pathways (i.e., PI3K/AKT/mTOR, WNT/β-catenin, NOTCH, SHH/GLI, among others) involved in OS pathophysiology. Despite different players and complexities, many commonalities have been described, among which the nuclear factor kappa B (NF-κB) stands out. Its altered activation is pervasive in cancer, with pleiotropic action on many disease-relevant traits. Thus, in the scope of this article, we highlight the evidence of NF-κB dysregulation in OS and its integration with other cancer-related pathways while we summarize the repertoire of compounds that have been described to interfere with its action. In silico strategies were used to demonstrate that NF-κB is closely coordinated with other commonly dysregulated signaling pathways not only by functionally interacting with several of their members but also by actively participating in the regulation of their transcription. While existing inhibitors lack selectivity or act indirectly, the therapeutic potential of targeting NF-κB is indisputable, first for its multifunctionality on most cancer hallmarks, and secondly, because, as a common downstream effector of the many dysregulated pathways influencing OS aggressiveness, it turns complex regulatory networks into a simpler picture underneath molecular heterogeneity.

Metabolomics analysis of amino acid and fatty acids in colorectal cancer patients based on tandem mass spectrometry

Metabolic differences between colorectal cancer (CRC) and NI (NI) play an important role in early diagnoses and in-time treatments. We investigated the metabolic alterations between CRC patients and NI, and identified some potential biomarkers, and these biomarkers might be used as indicators for diagnosis of CRC. In this study, there were 79 NI, 50 CRC I patients, 52 CRC II patients, 56 CRC III patients, and 52 CRC IV patients. MS-MS was used to measure the metabolic alterations. Univariate and multivariate data analysis and metabolic pathway analysis were applied to analyze metabolic data and determine differential metabolites. These indicators revealed that amino acid and fatty acids could separate these groups. Several metabolites indicated an excellent variables capability in the separation of CRC patients and NI. Ornithine, arginine, octadecanoyl carnitine, palmitoyl carnitine, adipoyl carnitine, and butyryl carnitine/propanoyl carnitine were selected to distinguish the CRC patients and NI. And methionine and propanoyl carnitine, were directly linked to different stages of CRC. Receiver operating characteristics curves and variables importance in projection both represented an excellent performance of these metabolites. In conclusion, we assessed the difference between CRC patients and NI, which supports guidelines for an early diagnosis and effective treatment.

Oxidative stress-mediated mitochondrial apoptosis induced by the acaricide, fenpyroximate, on cultured human colon cancer HCT 116 cells

Fenpyroximate (FEN) is an acaricide that inhibits mitochondrial electron transport at the NADH-coenzyme Q oxidoreductase (complex I). The present study was designed to investigate the molecular mechanisms underling FEN toxicity on cultured human colon carcinoma cells (HCT116). Our data showed that FEN induced HCT116 cell mortality in a concentration dependent manner. FEN arrested cell cycle in G0/G1 phase and increased DNA damage as assessed by comet assay. Induction of apoptosis was confirmed in HCT116 cells exposed to FEN by AO-EB staining and Annexin V-FITC/PI double staining assay. Moreover, FEN induced a loss in mitochondrial membrane potential (MMP), increased p53 and Bax mRNA expression and decreased bcl2 mRNA level. An increase in caspase 9 and caspase 3 activities was also detected. All toghether, these data suggest that FEN induce apoptosis in HCT116 cells via mitochondrial pathway. To check the implication of oxidative stress in FEN-induced cell toxicity, we examined the oxidative stress statue in HCT116 cells exposed to FEN and we tested the effect of a powerful antioxidant, N-acetylcystein (NAC), on FEN-caused toxicity. It was observed that FEN enhanced ROS generation and MDA levels and disturbed SOD and CAT activities. Besides, cell treatment with NAC significantly protected cells from mortality, DNA damage, loss of MMP, and caspase 3 activity induced by FEN. To the best of our knowledge, this is the first study showing that FEN induced mitochondrial apoptosis via ROS generation and oxidative stress.

Magnolol Loaded on Carboxymethyl Chitosan Particles Improved the Antimicrobial Resistance and Storability of Kiwifruits

Magnolol is a natural compound extracted from the traditional Chinese medicine Magnolia officinalis, which exhibits antimicrobial properties. However, magnolol is insoluble in water and consists of a phenolic hydroxyl group, which is volatile; these factors hinder its application. In this study, a safe and environmentally friendly method to improve the microbial resistance and storability of harvested fruits is developed using the water-soluble carrier carboxymethyl chitosan (CMCS) and magnolol. Magnolol was loaded on CMCS particles to form Magnolol@CMCS antimicrobial particles, a preservation coating agent. Magnolol@CMCS particles effectively solved the problems of water insolubility and agglomeration of magnolol and reduced the size distribution D50 value of magnolol from 0.749 to 0.213 μm. Magnolol@CMCS particles showed greater toxicity against Staphylococcus aureus, Escherichia coli, and Botryosphaeria dothidea than that of magnolol alone, with effective medium concentration (EC50) values of 0.9408, 142.4144, and 8.8028 μg/mL, respectively. Kiwifruit treated with the Magnolol@CMCS solution showed delayed changes in fruit hardness and soluble solid and dry matter contents and significantly higher ascorbic acid (vitamin C) and soluble total sugar contents and sugar:acid ratios compared with that of the control fruit. In addition, no disease spots were observed on fruit treated with the Magnolol@CMCS solution within 7 days after inoculation with B. dothidea. In conclusion, Magnolol@CMCS particles showed antimicrobial activity on harvested fruits, effectively delayed the hardness and nutritional changes of fruits during storage, and improved the storability of kiwifruit.

Magnolol as a Potential Anticancer Agent: A Proposed Mechanistic Insight

Cancer is a serious disease with high mortality and morbidity worldwide. Natural products have served as a major source for developing new anticancer drugs during recent decades. Magnolol, a representative natural phenolic lignan isolated from Magnolia officinali, has attracted considerable attention for its anticancer properties in recent years. Accumulating preclinical studies have demonstrated the tremendous therapeutic potential of magnolol via a wide range of pharmacological mechanisms against cancer. In this review, we summarized the latest advances in preclinical studies investigating anticancer properties of magnolol and described the important signaling pathways explaining its underlying mechanisms. Magnolol was capable of inhibiting cancer growth and metastasis against various cancer types. Magnolol exerted anticancer effects through inhibiting proliferation, inducing cell cycle arrest, provoking apoptosis, restraining migration and invasion, and suppressing angiogenesis. Multiple signaling pathways were also involved in the pharmacological actions of magnolol against cancer, such as PI3K/Akt/mTOR signaling, MAPK signaling and NF-κB signaling. Based on this existing evidence summarized in the review, we have conclusively confirmed magnolol had a multi-target anticancer effect against heterogeneous cancer disease. It is promising to develop magnolol as a drug candidate for cancer therapy in the future.

Thiacloprid-induced hepatotoxicity in zebrafish: Activation of the extrinsic and intrinsic apoptosis pathways regulated by p53 signaling pathway

Thiacloprid (THCP) is one of the major neonicotinoid insecticides, and its wide use has led to high detection in various media of aquatic environment, posing potential risks to aquatic organisms. This study was focused on the phenotypic responses and mechanisms of toxicity in zebrafish (Danio rerio) upon treatment with waterborne THCP (0.4, 4 and 40 μM) for 21 days in vivo or 412.9 μM for 24 h in vitro. In vivo, we found that THCP induced severe oxidative stress, hepatic abnormalities, leakage of alanine aminotransferase and aspartate aminotransferase and apoptosis. The analysis of RNA-sequencing suggested the activation of the p53 signaling pathway under THCP exposure. The following in vitro study showed that THCP intoxication activated reactive oxygen species (ROS)-dependent p53 signaling pathway and induced hepatotoxicity in the zebrafish liver cells. The addition of p53 inhibitor pifithrin-α (10 μM) exerted protection against of THCP-induced hepatotoxicity by reducing oxidative stress and inhibiting the p53 signaling pathway and apoptosis. Moreover, gene expression analyses indicated that both the extrinsic and intrinsic apoptosis pathways were involved in apoptosis induced by p53 activation. Overall, our results suggest that activation of the p53 signaling pathway is an important mechanism of THCP-induced hepatotoxicity.

Magnolol-loaded Cholesteryl Biguanide Conjugate Hydrochloride Nanoparticles for Triple-negative Breast Cancer Therapy

The potential of combination therapy using nanoparticle delivery systems in improving triple-negative breast cancer treatment efficacy remains to be explored. Here, we report a novel nanoparticle system using a cholesterol biguanide conjugate hydrochloride (CBH) as both a drug and carrier to load magnolol (MAG). Poly(ethylene glycol)-poly(lactic-co-glycolic acid) (mPEG-PLGA) and aminoethyl anisamide-poly(ethylene glycol)-poly(lactic-co-glycolic acid) (AEAA-PEG-PLGA) were added to form nanoparticles. Nanoparticles accumulated most in tumor tissues when the weight ratio of AEAA-PEG-PLGA to mPEG-PLGA was 4:1. MAG and CBH exerted a synergistic inhibitory effect on 4T1 cells. An in vitro study showed that nanoparticles displayed the highest tumor cell uptake rate, highest apoptosis rate, and strongest inhibitory effect on tumor cell migration and monoclonal formation. CBH might promote nanoparticle uptake by cells and lysosomal escape. After intravenous administration to mice with 4T1 breast tumors in situ, the nanoparticles inhibited tumor growth without obvious toxicity. Western blot results showed that nanoparticles altered the levels of p53, p-AKT, and p-AMPK in the tumor tissue. Moreover, cell apoptosis was found in the same area of H&E-stained and TUNEL-stained tumors treated with the nanoparticles. Collectively, this nanoparticle system provides a novel combination drug delivery strategy for treating triple-negative breast cancer.

Magnolol attenuates the locomotor impairment, cognitive deficit, and neuroinflammation in Alzheimer's disease mice with brain insulin resistance via up-regulating miR-200c

In this study, we aimed to investigate the effect of Magnolol on Alzheimer's disease (AD). After the model of streptozotocin-induced AD mice with brain insulin resistance was established, the mice were treated with Magnolol or miR-200c antagomiR. The abilities of ambulations, rearings, discrimination, spatial learning, and memory were evaluated by open-field test (OFT), novel object recognition (NOR), and morris water maze (MWM) tests. The levels of malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), and miR-200c in the mice hippocampus were evaluated by enzyme-linked immunosorbent assay, Western blot, or Quantitative real-time Polymerase Chain Reaction. In AD mice model, streptozotocin induced the locomotor impairment and cognitive deficit, up-regulated levels of MDA, TNF-α, IL-6, and CRP, while down-regulated levels of GSH, SOD, and miR-200c. Magnolol increased the rearings numbers and discrimination index of AD mice in OFT and NOR tests. Magnolol increased the number of entries in the target quadrant and time spent in the target quadrant and decreased the escape latency of AD mice in the MWM test. Magnolol also down-regulated the levels of MDA, TNF-α, IL-6, and CRP, and up-regulated the levels of GSH, SOD, and miR-200c in the hippocampus tissues of AD mice. However, miR-200c antagomiR did the opposite and further offset the effects of the Magnolol on AD mice. Magnolol attenuated the locomotor impairment, cognitive deficit, and neuroinflammatory in AD mice with brain insulin resistance via up-regulating miR-200c.

Computational and Experimental Assessments of Magnolol as a Neuroprotective Agent and Utilization of UiO-66(Zr) as Its Drug Delivery System

The phenolic natural product magnolol exhibits neuroprotective properties through β-amyloid toxicity in PC-12 cells and ameliorative effects against cognitive deficits in a TgCRND8 transgenic mice model. Its bioavailability and blood-brain barrier crossing ability have been significantly improved using the metal-organic framework (MOF) UiO-66(Zr) as a drug delivery system (DDS). To investigate the neuroprotective effects of the Zr-based DDS, magnolol and magnolol-loaded-UiO-66(Zr) (Mag@UiO-66(Zr)) were evaluated for inhibitory activity against β-secretase and AlCl₃-induced neurotoxicity. Due to the moderate inhibition observed for magnolol in vitro, in silico binding studies were explored against β-secretase along with 11 enzymes known to affect Alzheimer's disease (AD). Favorable binding energies against CDK2, CKD5, MARK, and phosphodiesterase 3B (PDE3B) and dynamically stable complexes were noted through molecular docking and molecular dynamic simulation experiments, respectively. The magnolol-loaded DDS UiO-66(Zr) also showed enhanced neuroprotective activity against two pathological indices, namely, neutrophil infiltration and apoptotic neurons, in addition to damage reversal compared to magnolol. Thus, MOFs are promising drug delivery platforms for poorly bioavailable drugs.

Arctigenin Triggers Apoptosis and Autophagy via PI3K/Akt/mTOR Inhibition in PC-3M Cells

Arctigenin (ARG), a natural lignans compound isolated from Arctium lappa L. In this study, the anti-tumor effect of ARG on prostate cancer cell PC-3M and the mechanism of apoptosis and autophagy induced by phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway were discussed, and further confirmed by the joint treatment of ARG and PI3K inhibitor LY294002. Here, the effect of ARG on cell viability was evaluated in PC-3M cells by Cell Counting Kit-8 reagent (CCK-8) assay. After the treatment of ARG, colony formation assay was used to detect the anti-proliferation effect. Annexin V-fluoresceine isothiocyanate/propidium iodide (FITC/PI) kit and 4',6-diamidino-2-phenylindole (DAPI) staining were used to detect the apoptosis level, and cell cycle changes were analyzed by flow cytometry. The expression of autophagy was detected by acridine orange staining. In addition, the expression levels of apoptosis and autophagy-related proteins were analyzed by Western blot. The result showed that different concentrations of ARG inhibited the proliferation of PC-3M cells. DAPI staining and flow cytometry showed that ARG induced PC-3M cell apoptosis and arrested cell in G0/G1 phase. Acridine orange staining showed that ARG induced autophagy in PC-3M cells. Western blot experiments showed that ARG inhibited the expression of Bcl-2, promoted the expression of Bax and cleaved caspase-3. At the same time, the expression of autophagy-related proteins LC3B-II and Beclin-1 increased after ARG treatment, but P62 decreased. In addition, further studies have shown that treatment with LY294002 enhanced the effects of ARG on the expression of proteins associated with apoptosis and autophagy, indicating that ARG may induce apoptosis and autophagy through PI3K/Akt/mTOR pathway.

The role of Notch ligand Jagged1 in osteosarcoma proliferation, metastasis, and recurrence

BACKGROUND

Osteosarcoma is the most common primary bone cancer occurring in young adults and the 5-year survival rate of patients with metastatic osteosarcoma is less than 30% due to high metastatic recurrence and drug resistance. Notch is a highly conserved cell to cell signaling pathway in evolution, and Jagged1 is an important ligand of Notch. Although some studies have found that Notch receptors and ligands including Jagged1 were highly expressed in osteosarcoma tissues and osteosarcoma cells, the role of Jagged1 in osteosarcoma progression and metastasis are still not clear.

METHODS

Tumor tissues were collected from 68 patients and immunohistochemical staining was employed to group these patients by expression of Jagged1. Real-time quantitative PCR and Western blotting were used to detect the expression of Jagged1. We used siRNA to knockdown the expression of Jagged1 in F5M2 cells. Colony formation assay and MTT were employed to detect and analyze the proliferation of F5M2 cells with or without knockdown of Jagged1. Transwell assay were used to detect the migration and invasion of F5M2 cells.

RESULTS

In this study, we found that the high expression of Jagged1 is closely related to the metastasis and recurrence of osteosarcoma in 68 clinical specimens. The expression of Jagged1 in F5M2 cells with high metastasis was significantly higher than that in F4 cells with low metastasis. Knockdown of Jagged1 led to lower ability of proliferation, migration, and invasion in F5M2 cells.

CONCLUSION

The high expression of Jagged1 is closely related to the metastasis and recurrence of osteosarcoma. Knockdown of Jagged1 significantly reduced the proliferation, migration, and invasion of osteosarcoma cells. Our results suggested that knockdown of Jagged1 may be a potentially effective treatment for metastatic osteosarcoma.

Magnolol Suppresses Pancreatic Cancer Development In Vivo and In Vitro via Negatively Regulating TGF-β/Smad Signaling

Magnolol, a hydroxylated biphenyl extracted from Magnolia officinalis, has recently drawn attention due to its anticancer potential. The present study was aimed to explore the effects of Magnolol on restraining the proliferation, migration and invasion of pancreatic cancer in vivo and in vitro. Magnolol showed significant anti-growth effect in an orthotopic xenograft nude mouse model, and immunohistochemical staining of the xenografts revealed that Magnolol suppressed vimentin expression and facilitated E-cadherin expression. The cytoactive detection using CCK-8 assay showed Magnolol inhibited PANC-1 and AsPC-1 concentration-dependently. Scratch healing assay and the Transwell invasion assay proved the inhibiting effects of Magnolol on cellular migration and invasion at a non-cytotoxic concentration. Western blot and rt-PCR showed that Magnolol suppressed epithelial-mesenchymal-transition by increasing the expression level of E-cadherin and decreasing those of N-cadherin and vimentin. Magnolol suppressed the TGF-β/Smad pathway by negatively regulating phosphorylation of Smad2/3. Moreover, TGF-β1 impaired the antitumor effects of Magnolol in vivo. These results demonstrated that Magnolol can inhibit proliferation, migration and invasion in vivo and in vitro by suppressing the TGF-β signal pathway and EMT. Magnolol could be a hopeful therapeutic drug for pancreatic malignancy.

Magnolol Enhances the Therapeutic Effects of TRAIL through DR5 Upregulation and Downregulation of c-FLIP and Mcl-1 Proteins in Cancer Cells

Magnolol is a biologically active compound, isolated from the Chinese herb Magnolia, that regulates antiproliferative, anticancer, antiangiogenic and antimetastatic activities. We found that magnolol sensitizes TRAIL-induced apoptotic cell death via upregulation of DR5 and downregulation of cellular FLICE-inhibitory protein (c-FLIP) and Mcl-1 in cancer cells, but not in normal cells. Mechanistically, magnolol increased ATF4-dependent DR5 expression at the transcription level, and knockdown of ATF4 markedly inhibited magnolol-induced DR5 upregulation. Silencing DR5 with siRNA prevented combined treatment with magnolol and TRAIL-induced apoptosis and PARP cleavage. Magnolol induced proteasome-mediated Mcl-1 downregulation, while magnolol-induced c-FLIP downregulation was regulated, at least in part, by lysosomal degradation. Our results revealed that magnolol enhanced TRAIL-induced apoptosis via ATF4-dependent DR5 upregulation and downregulation of c-FLIP and Mcl-1 proteins.

CCT128930 induces G1-phase arrest and apoptosis and synergistically enhances the anticancer efficiency of VS5584 in human osteosarcoma cells

Osteosarcoma is a highly invasive primary malignant bone tumor. PI3K/mTOR pathway plays a key role in tumor progression, and inhibition of PI3K/mTOR pathway represents a novel strategy in therapy of osteosarcoma. CCT128930 and VS5584 are both inhibitors of PI3K/mTOR, but the anticancer mechanism of CCT128930 or/and VS5584 against human osteosarcoma cells remains unclear. Herein, U2OS and MG63 human osteosarcoma cells were cultured, and the anticancer effects of CCT128930 alone and the combined effect of CCT128930 and VS5584 against human osteosarcoma cells were explored. The results showed that CCT128930 as PI3K/mTOR inhibitor effectively inhibited p-p70 and p-AKT expression and dose-dependently inhibited U2OS cells and MG63 human osteosarcoma cells growth. Further studies found that CCT128930 triggered significant G-1 phase arrest and apoptosis, as convinced by the dysfunction of p27, Cyclin B1, Cyclin D1 and Cdc2, and PARP cleavage and caspase-3 activation. Moreover, CCT128930 treatment obviously enhanced VS5584-induced growth inhibition and apoptosis in human osteosarcoma cells, followed by enhanced PARP cleavage and caspase-3 activation. Taken together, CCT128930 alone or combined treatment with CCT128930 and VS5584 both effectively inhibited human osteosarcoma cells growth by induction of G1-phase arrest and apoptosis through regulating PI3K/mTOR and MAPKs pathways.

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)]- β-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.