Miltirone induced mitochondrial dysfunction and ROS-dependent apoptosis in colon cancer cells

Pyroptosis: shedding light on the mechanisms and links with cancers

Pyroptosis, a novel form of programmed cell death (PCD) discovered after apoptosis and necrosis, is characterized by cell swelling, cytomembrane perforation and lysis, chromatin DNA fragmentation, and the release of intracellular proinflammatory contents, such as Interleukin (IL) 8, IL-1β, ATP, IL-1α, and high mobility group box 1 (HMGB1). Our understanding of pyroptosis has increased over time with an increase in research on the subject: gasdermin-mediated lytic PCD usually, but not always, requires cleavage by caspases. Moreover, new evidence suggests that pyroptosis induction in tumor cells results in a strong inflammatory response and significant cancer regression, which has stimulated great interest among scientists for its potential application in clinical cancer therapy. It's worth noting that the side effects of chemotherapy and radiotherapy can be triggered by pyroptosis. Thus, the intelligent use of pyroptosis, the double-edged sword for tumors, will enable us to understand the genesis and development of cancers and provide potential methods to develop novel anticancer drugs based on pyroptosis. Hence, in this review, we systematically summarize the molecular mechanisms of pyroptosis and provide the latest available evidence supporting the antitumor properties of pyroptosis, and provide a summary of the various antitumor medicines targeting pyroptosis signaling pathways.

Natural products and mitochondrial allies in colorectal cancer therapy

Colorectal cancer (CRC) is a globally prevalent malignancy with a high potential for metastasis. Existing cancer treatments have limitations, including drug resistance and adverse effects. Researchers are striving to develop effective therapies to address these challenges. Impressively, contemporary research has discovered that many natural products derived from foods, plants, insects, and marine invertebrates can suppress the progression, metastasis, and invasion of CRC. In this review, we conducted a comprehensive search of the CNKI, PubMed, Embase, and Web of Science databases from inception to April 2023 to evaluate the efficacy of natural products targeting mitochondria to fight against CRC. Mitochondria are intracellular energy factories involved in cell differentiation, signal transduction, cell cycle regulation, apoptosis, and tumorigenesis. The identified natural products have been classified and summarized based on their mechanisms of action. These findings indicate that natural products can induce apoptosis in colorectal cancer cells by inhibiting the mitochondrial respiratory chain, ROS elevation, disruption of mitochondrial membrane potential, the release of pro-apoptotic factors, modulation of the Bcl-2 protein family to facilitate cytochrome c release, induction of apoptotic vesicle activity by activating the caspase protein family, and selective targeting of mitochondrial division. Furthermore, diverse apoptotic signaling pathways targeting mitochondria, such as the MAPK, p53, STAT3, JNK and AKT pathway, have been triggered by natural products. Natural products such as diosgenin, allopurinol, and clausenidin have demonstrated low toxicity, high efficacy, and multi-targeted properties. Mitochondria-targeting natural products have great potential for overcoming the challenges of CRC therapy.

Dicoumarol: from chemistry to antitumor benefits

Dicoumarol, a coumarin-like compound, is known for its anticoagulant properties associated with the ability to inhibit vitamin K, being prescribed as a drug for several decades. The pharmaceutical value of dicoumarol turned it into a focus of chemists' attention, aiming its synthesis and of dicoumarol derivatives, bringing to light new methodologies. In recent years, several other bioactive effects have been claimed for dicoumarol and its derivatives, including anti-inflammatory, antimicrobial, antifungal, and anticancer, although the mechanisms of action underlying them are mostly not disclosed and additional research is needed to unravel them. This review presents a state of the art on the chemistry of dicoumarols, and their potential anticancer characteristics, highlighting the mechanisms of action elucidated so far. In parallel, we draw attention to the lack of in vivo studies and clinical trials to assess the safety and efficacy as drugs for later application.

Nardoguaianone L Isolated from Nardostachys jatamansi Improved the Effect of Gemcitabine Chemotherapy via Regulating AGE Signaling Pathway in SW1990 Cells

Pancreatic cancer is the seventh leading cause of cancer-related death worldwide and is known as “the king of cancers”. Currently, gemcitabine (GEM) as the clinical drug of choice for chemotherapy of advanced pancreatic cancer has poor drug sensitivity and ineffective chemotherapy. Nardoguaianone L (G-6) is a novel guaiane-type sesquiterpenoid isolated from Nardostachys jatamansi DC., and it exhibits anti-tumor activity. Based on the newly discovered G-6 with anti-pancreatic cancer activity in our laboratory, this paper aimed to evaluate the potential value of the combination of G-6 and GEM in SW1990 cells, including cell viability, cell apoptosis, colony assay and tandem mass tags (TMT) marker-based proteomic technology. These results showed that G-6 combined with GEM significantly inhibited cell viability, and the effect was more obvious than that with single drug. In addition, the use of TMT marker-based proteomic technology demonstrated that the AGE-RAGE signaling pathway was activated after medication-combination. Furthermore, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) assays were used to validate the proteomic results. Finally, apoptosis was detected by flow cytometry. In conclusion, G-6 combined with GEM induced an increase in ROS level and a decrease in MMP in SW1990 cells through the AGE-RAGE signaling pathway, ultimately leading to apoptosis. G-6 improved the effect of GEM chemotherapy and may be used as a potential combination therapy for pancreatic cancer.

Miltirone Attenuates Reactive Oxygen Species-Dependent Neuronal Apoptosis in MPP+-Induced Cell Model of Parkinson's Disease Through Regulating the PI3K/Akt Pathway

Miltirone is a phenanthrene-quinone derived from Salvia miltiorrhiza Bunge with anti-inflammatory and anti-oxidant effects. Our study aimed to explore the protective effect of miltirone on 1-methyl-4-phenylpyridinium (MPP⁺)-induced cell model of Parkinson's disease (PD). PharmMapper database was employed to predict the targets of miltirone. PD-related genes were identified using GeneCards database. The overlapping genes between miltirone and PD were screened out using Venn diagram. KEGG analysis was performed using DAVID and KOBAS databases. Cell viability, reactive oxygen species (ROS) generation, apoptosis, and caspase-3 activity were detected by CCK-8 assay, a ROS assay kit, TUNEL, and caspase-3 activity assay, respectively. Effect of miltirone on the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway was explored by western blot analysis. A total of 214 targets of miltirone and 372 targets related to PD were attained, including 29 overlapping targets. KEGG analysis demonstrated that the 29 overlapping targets were both significantly enriched in the PI3K/Akt pathway. MPP⁺ stimulation reduced the cell viability in SH-SY5Y cells and neuronal primary cultures derived from human brain. Miltirone or N-acetylcysteine (NAC) attenuated MPP⁺-induced reduction in cell viability, ROS production, SOD activity reduction, apoptosis, and increase of caspase-3 activity. Additionally, miltirone recuperated MPP⁺-induced inactivation of the PI3K/Akt pathway. Moreover, treatment with LY294002, an inhibitor of the PI3K/Akt pathway, reversed the inhibitory effect of miltirone on MPP⁺-induced ROS generation and apoptosis in SH-SY5Y cells and neuronal primary cultures. In conclusion, miltirone attenuated ROS-dependent apoptosis in MPP⁺-induced cellular model of PD through activating the PI3K/Akt pathway.

Farrerol suppresses the progression of laryngeal squamous cell carcinoma via the mitochondria-mediated pathway

PURPOSE

In the context of well-known inhibitory effects of Farrerol on the invasion of lung squamous cell carcinoma cells, the unexplored effect and regulatory mechanism of Farrerol on laryngeal squamous cell carcinoma (LSCC) emerged as the target in this study.

METHODS

After treatment with Farrerol alone, or together with MitoTempo, the viability, apoptosis, cell cycle distribution, migration, and invasion of LSCC cells were measured using MTT, flow cytometry, wound-healing, and transwell assays, respectively. Meanwhile, the levels of cytochrome C (Cyt C), Cleaved caspase-3/9, Cyclin D1, E-cadherin, N-cadherin, and Vimentin in LSCC cells were evaluated by Western blot; the reactive oxygen species (ROS) formation intensity and the disruption of mitochondrial membrane potential (MMP) of LSCC cells were assessed using flow cytometry; and the effect of Farrerol on xenograft tumor formation was evaluated in animal experiment.

RESULTS

Farrerol (10, 20, 50 μM) inhibited the viability, proliferation, cell cycle progression, migration and invasion, but promoted apoptosis, ROS formation intensity and disruption of MMP of LSCC cells. Moreover, Farrerol up-regulated Cyt C (in the cytoplasm), Cleaved caspase-3/9 and E-cadherin levels, but down-regulated Cyclin D1, N-cadherin and Vimentin levels in LSCC cells. Additionally, we uncovered that MitoTempo reversed the promoting effects of Farrerol on ROS formation intensity, apoptosis, and Cyt C and Cleaved caspase-3/9 levels in LSCC cells, while improving the disruption of MMP in Farrerol-treated LSCC cells. Also, Farrerol lessened the volume and weight of mice tumors.

CONCLUSIONS

Farrerol suppressed the migration, invasion, and induced the apoptosis of LSCC cells via the mitochondria-mediated pathway.

Chitosan-tripolyphosphate nanoparticles-mediated co-delivery of MTHFD1L shRNA and 5-aminolevulinic acid for combination photodynamic-gene therapy in oral cancer

BACKGROUND

Rationally designed nanostructured materials can produce improved drug carriers that play an increasingly important role in cancer treatment. In comparison with conventional drug combination approaches, using co-delivery systems of multiple drugs achieves sophisticated targeting strategies and multifunctionality.

METHODS

First, a nano-co-delivery of chitosan/tripolyphosphate (CS-TPP) was synthesized and characterized combining 5-aminolevulinic acid photodynamic therapy (ALA-PDT) with methylenetetrahydrofolate dehydrogenase 1-like (MTHFD1L) shRNA. In this report, we investigated the efficacy of the simultaneous delivery of shRNA/photosensitizer on the gene expression of oral squamous cell carcinoma (OSCC) cells. The efficacy of CS-TPP-(shMTHFD1L-ALA)-PDT in inducing apoptosis and in generating of reactive oxygen species (ROS) in vitro was then assessed by Annexin V-PI and DCFH-DA assays respectively. In vivo therapeutic experiments were conducted in well-established orthotopic animal models of HNSCC.

RESULTS

The results showed that the CS-TPP-(shMTHFD1L-ALA) nanoparticles (NPs) were approximately 145 nm in size. The cytotoxicity of OSCC cells was significantly increased by co-delivery of MTHFD1L shRNA and ALA-PDT compared with other groups. Furthermore, individual and combined therapies revealed remarkable pro-apoptotic, ROS and anti-tumorigenesis effects, and CS-TPP-(shMTHFD1L-ALA)-PDT had additive effects in vitro and in vivo.

CONCLUSION

These observations indicate that CS-TPP-(shMTHFD1L-ALA) NPs may be an ideal candidate for gene/photosensitizer delivery.

Mechanism of piperine in affecting apoptosis and proliferation of gastric cancer cells via ROS-mitochondria-associated signalling pathway

Piperine (PIP), the main active ingredient in pepper, belongs to the cinnamamide alkaloid. PIP has been found to have functions, including anti-oxidation, immune regulation, anti-tumour and promotion of drug metabolism. The present study was mainly designed to reveal the anti-tumour effect of PIP against gastric cancer and the relevant mechanism. In brief, the undifferentiated human gastric cancer cell HGC-27 was used, which was treated with different concentrations of PIP. As a result, PIP could inhibit proliferation and induce apoptosis of HGC-27 cells in a dose-dependent manner. The mechanism of PIP was associated with ROS increase and mitochondrial damage, simultaneously, the expression of key proteins of apoptosis was affected, including Bcl-2, Bax, Cyt-c, Caspase-9 and Caspase-3. Pre-treatment of ROS scavenger NAC HGC-27 cells could significantly reduce PIP-induced apoptosis and inhibit the activation of apoptotic signals. Consistently, PIP could induce ROS to increase and activate apoptotic signals in the animal model. Therefore, the present study showed that PIP can induce the generation of ROS, thereby promoting the activation of mitochondrial apoptotic pathway and exerting anti-tumour effects.

Inflammation-related pyroptosis, a novel programmed cell death pathway, and its crosstalk with immune therapy in cancer treatment

In recent decades, chemotherapies targeting apoptosis have emerged and demonstrated remarkable achievements. However, emerging evidence has shown that chemoresistance is mediated by impairing or bypassing apoptotic cell death. Several novel types of programmed cell death, such as ferroptosis, necroptosis, and pyroptosis, have recently been reported to play significant roles in the modulation of cancer progression and are considered a promising strategy for cancer treatment. Thus, the switch between apoptosis and pyroptosis is also discussed. Cancer immunotherapy has gained increasing attention due to breakthroughs in immune checkpoint inhibitors; moreover, ferroptosis, necroptosis, and pyroptosis are highly correlated with the modulation of immunity in the tumor microenvironment. Compared with necroptosis and ferroptosis, pyroptosis is the primary mechanism for host defense and is crucial for bridging innate and adaptive immunity. Furthermore, recent evidence has demonstrated that pyroptosis exerts benefits on cancer immunotherapies, including immune checkpoint inhibitors (ICIs) and chimeric antigen receptor T-cell therapy (CAR-T). Hence, in this review, we elucidate the role of pyroptosis in cancer progression and the modulation of immunity. We also summarize the potential small molecules and nanomaterials that target pyroptotic cell death mechanisms and their therapeutic effects on cancer.

Sodium Valproate, a Histone Deacetylase Inhibitor, Provokes Reactive Oxygen Species-Mediated Cytotoxicity in Human Hepatocellular Carcinoma Cells

BACKGROUND AND AIM

Sodium valproate (SV), a novel class of histone deacetylases (HDACs) inhibitors commonly used as an antiepileptic drug. HDAC inhibitors are known to possess anticancer potentials. In this study, we investigated the cytotoxic potential of SV in human hepatocellular carcinoma (HepG2 cells) cell line.

METHODS

MTT assay was used to analyze cytotoxicity. Intracellular ROS and cytochrome c expression were analyzed by fluorescence microscopy. Morphology-related apoptosis was analyzed by dual staining with acridine orange/ethidium bromide. Caspase 3 protein expression was investigated by Western blotting analysis.

RESULTS

Sodium valproate treatments in HepG2 cells caused significant and dose-dependent cytotoxicity. Intracellular ROS was remarkably increased in the cells which are treated with SV and caused early and late apoptosis as evidenced by dual staining. SV-treated cells expressed cytochrome c and caspase 3 protein expression.

CONCLUSION

These results suggest the cytotoxic potentials of SV in HepG2 cells. This study may give an important clue for the inclusion of SV as an adjuvant along with standard anticancer agents after necessary in vivo and clinical studies.

The ethyl acetate extraction of Pileostegia tomentella (ZLTE) exerts anti-cancer effects on H1299 cells via ROS-induced canonical apoptosis

Lung cancer is the leading cause of cancer death and the most common malignant tumor, the long-term survival of which has stagnated in the past several decades. Pileostegia tomentella Hand. Mazz is a traditional Chinese medicine called "Zhongliuteng" (ZLT) in the pharmacopeia, which has been proved to possess a potent anti-tumor effect on various cancers. In this study, the effects of ZLT N-butanol extraction (ZLTN) and ZLT ethyl acetate extraction (ZLTE) on the viability of non-small cell lung cancer cell (NSCLC) lines H1299 and A549 were evaluated. Here, we firstly reported that ZLTE significantly inhibited H1299 cells growth without affecting the release of lactate dehydrogenase (LDH). In addition, ZLTE induced caspase-dependent apoptosis in a concentration-dependent manner and increased the expression cleaved-PARP and decreased pro-caspase-3, pro-caspase-7, pro-caspase-8, and pro-caspase-9. Moreover, ZLTE increased the level of cellular reactive oxygen species (ROS) in H1299 cells to lead to apoptosis, which was reversed by N-acetyl-cysteine (NAC). Taken together, our results revealed that ZLTE induced caspase-dependent apoptosis via ROS generation, suggesting that ZLTE is a promising herbal medicine for the treatment of NSCLC.

A pharmacological review of dicoumarol: An old natural anticoagulant agent

Dicoumarol is an oral anticoagulant agent prescribed in clinical for decades. It is a natural hydroxycoumarin discovered from the spoilage of Melilotus officinalis (L.) Pall and is originally discovered as a rodenticide. Due to its structural similarity to that of vitamin K, it significantly inhibits vitamin K epoxide reductase and acts as a vitamin K antagonist. Dicoumarol is mainly used as an anticoagulant to prevent thrombogenesis and to cure vascular thrombosis. Other biological activities besides anticoagulants such as anticancer, antimicrobial, antiviral, etc., have also been documented. The side effects of dicoumarol raise safety concerns for clinical application. In this review, the physicochemical property, the pharmacological activities, the side effects, and the pharmacokinetics of dicoumarol were summarized, aiming to provide a whole picture of the "old" anticoagulant.

Miltirone induces cell death in hepatocellular carcinoma cell through GSDME-dependent pyroptosis

Pyroptosis is a form of programmed cell death, and recently described as a new molecular mechanism of chemotherapy drugs in the treatment of tumors. Miltirone, a derivative of phenanthrene-quinone isolated from the root of Salvia miltiorrhiza Bunge, has been shown to possess anti-cancer activities. Here, we found that miltirone inhibited the cell viability of either HepG2 or Hepa1-6 cells, and induced the proteolytic cleavage of gasdermin E (GSDME) in each hepatocellular carcinoma (HCC) cell line, with concomitant cleavage of caspase 3. Knocking out GSDME switched miltirone-induced cell death from pyroptosis to apoptosis. Additionally, the induction effects of miltirone on GSDME-dependent pyroptosis were attenuated by siRNA-mediated caspase three silencing and the specific caspase three inhibitor Z-DEVD-FMK, respectively. Miltirone effectively elicited intracellular accumulation of reactive oxygen species (ROS), and suppressed phosphorylation of mitogen-activated and extracellular signal-regulated kinase (MEK) and extracellular regulated protein kinases 1/2 (ERK1/2) for pyroptosis induction. Moreover, miltirone significantly inhibited tumor growth and induced pyroptosis in the Hepa1-6 mouse HCC syngeneic model. These results provide a new insight that miltirone is a potential therapeutic agent for the treatment of HCC via GSDME-dependent pyroptosis.

Helveticoside Exhibited p53-dependent Anticancer Activity Against Colorectal Cancer

BACKGROUND

Investigation into the anti-cancer activities of natural products and their derivatives represents an efficient approach to develop safe and effective chemotherapeutic agents for the treatment of colorectal cancer. Helveticoside is a biologically active component of the seed extract of Descurainia sophia. This compound has been reported to regulate the genes related to cell proliferation and apoptosis in lung cancer cells, however its anticancer activity has not been fully explored yet.

METHODS

Cell viability was evaluated by MTT and Trypan blue exclusion assay; cell apoptosis was measured by flow cytometry; mitochondrial membrane potential was determined by using JC1-mitochondrial membrane potential assay kit; protein levels were determined by western blot assay; in vivo tumor growth was assessed in a xenograft nude mice model.

RESULTS

The current study demonstrated the in vitro anti-cancer activity of helveticoside against colorectal cancer using colorectal cancer cells SW480 and HCT116. Moreover, induction of apoptosis was found to mediate the cytotoxic action of helveticoside on SW480 and HCT116 cells. Based on the decrease in the mitochondrial membrane potential, upregulation of Bax, downregulation of Bcl-2 and cleavage of caspase-3 and 9, apoptosis was induced by helveticoside via mitochondria-mediated intrinsic apoptotic signaling pathways in colorectal cancer cells. Besides, using p53-knockout SW480 cells, the cytotoxic action of helveticoside was found to be p53-dependent. More importantly, administration of helveticoside inhibited the growth of HCT116 cells derived-colorectal cancer xenograft in mice via activation of apoptosis.

CONCLUSIONS

Helveticoside might be a potential candidate for the development of novel chemotherapeutic agents for the treatment of colorectal cancer, while the potential toxic effects of helveticoside may be worthy of further investigations.

A Novel Indolizine Derivative Induces Apoptosis Through the Mitochondria p53 Pathway in HepG2 Cells

Indolizine derivatives are a class of compounds with excellent biological activity. In this study, a series of indolizine derivatives, compound 1 (C1), compound 2 (C2), compound 3 (C3), and compound 4 (C4), were synthesized. 3-(4,5-dimethylthiazole)-2,5-diphenyltetraazolium bromide (MTT) assay was used to evaluate their cytotoxicity against HepG2 (p53-wild), A549, and HeLa cell lines. HepG2 cells apoptosis induced by C3 was determined using Hoechst staining and acridine orange/ethidium bromide staining. Cells’ apoptotic ratio was measured by Annexin V–FITC/PI double staining. Changes in mitochondrial membrane potential and intracellular reactive oxygen species (ROS) in HepG2 cells after C3 treatment were determined. Immunofluorescence staining and Western blot analysis were carried out to detect p53 levels and analyze the apoptosis-associated proteins, respectively. Moreover, the cytotoxic activity of C3 was examined in two other hepatocellular carcinoma (HCC) cell lines with different p53 status including Huh-7 cells (p53-mutant) and Hep3B cells (p53-null). The results indicated that C3 showed stronger inhibition towards HepG2 cells than other cell lines. Fluorescent staining and flow cytometry analysis confirmed that C3 induced apoptosis of HepG2 cells. C3 could also increase intracellular ROS and cause a decrease in the mitochondrial membrane potential. C3 promoted p53 activation and increased p53 accumulation in nuclei. The expression of p53 and Bax was increased with the down-regulation of Bcl-2, which promoted the release of cytochrome c and caspase-3 activation. Collectively, the study demonstrated that C3 caused HepG2 cell apoptosis via the mitochondria p53 pathway. These results inspired us to further develop indolizine derivatives as potential potent inhibitors against liver cancer.

Pharmacological actions of miltirone in the modulation of platelet function

Salvia miltiorrhiza Bunge contains various active constituents, some of which have been developed as commercially available medicine. Moreover, some other ingredients in Salvia miltiorrhiza play roles in anti-platelet activity. The aim of the present study was to investigate the effects and the underlying mechanism of miltirone, a lipophilic compound of Salvia miltiorrhiza Bunge. The ability of miltirone to modulate platelet function was investigated by a variety of in vitro and in vivo experiments. Platelet aggregation and dense granule secretion induced by various agonists were measured with platelet aggregometer. Clot retraction and spreading were imaged by digital camera and fluorescence microscope. Ferric chloride-induced carotid injury model and pulmonary thromboembolism model were used to check miltirone antithrombotic effect in vivo. To elucidate the mechanisms of anti-platelet activity of miltirone, flow cytometry and western blotting were performed. Miltirone (2, 4, 8 µM) was shown to suppress platelet aggregation, dense granule, and α granule secretion in a dose-dependent manner. Meanwhile, miltirone inhibited the clot retraction and spreading of washed platelets. It reduced the phosphorylation of PLCγ2, PKC, Akt, GSK3β and ERK1/2 in the downstream signal pathway of collagen receptor. It also reduced the phosphorylation of Src and FAK in the integrin αIIbβ3-mediated "outside-in" signaling, while it did not suppress the phosphorylation of β3. In addition, miltirone prolonged the occlusion time and reduced collagen/epinephrine-induced pulmonary thrombi. Miltirone suppresses platelet "inside-out" and "outside-in" signaling by affecting PLCγ₂/PKC/ERK1/2, PI3K/Akt, and Src/FAK signaling. Therefore, miltirone might represent a potential anti-platelet candidate for the prevention of thrombotic disorders.

Senkyunolide H protects against MPP+-induced apoptosis via the ROS-mediated mitogen-activated protein kinase pathway in PC12 cells

Senkyunolide H (SNH) is a phthalide isolated from the rhizome of Ligusticum chuanxiong Hort. that has been reported to have several pharmacological activities, including anti-atherosclerotic, antiproliferative, and cytoprotective effects. In this study, we investigated the neuroprotective effects and potential mechanisms of SNH against 1-methyl-4-phenylpyridinium (MPP⁺)-induced oxidative stress. We demonstrated that SNH pretreatment significantly attenuated MPP⁺-induced neurotoxicity and apoptosis in PC12 cells. In addition, SNH attenuated the effect of MPP⁺ on the expression of the pro-apoptotic factors Bax and caspase-3. Meanwhile, SNH prevented oxidative stress by reducing reactive oxygen species generation, mitochondrial membrane potential loss, cytochrome C release, and malondialdehyde levels while increasing antioxidant enzyme activity (e.g., superoxide dismutase, catalase, and glutathione peroxidase). In addition, SNH inhibited nuclear accumulation of nuclear factor-κB and c-Jun N-terminal kinase and phosphorylation p38 mitogen-activated protein kinases (MAPKs). Overall, this investigation provides novel evidence that SNH exerts neuroprotective effects via the ROS-mediated MAPK pathway and represents a potential preventive or therapeutic agent for neuronal disorders.

Ornithine aminotransferase promoted the proliferation and metastasis of non-small cell lung cancer via upregulation of miR-21

The incidence and mortality of lung cancer ranked the first among all types of cancer in China, and non-small cell lung cancer (NSCLC) is the most common type of lung cancer accounting for 85% of all lung cancers. Given that the survival rate of patients with advanced NSCLC is still poor nowadays, identification of novel therapeutic targets and the development of effective therapies are desired for the treatment of NSCLC in clinics. In this study, we reported the upregulation of ornithine aminotransferase (OAT) in NSCLC cells and clinical tumor samples as well as its association with the advanced TNM stage, metastasis, and poor tumor differentiation of lung cancer. Using different NSCLC cell lines, we demonstrated that OAT promoted the proliferation, invasion, and migration, inhibited the apoptosis, and altered cell cycle of NSCLC cells; besides, the involvement of OAT-miR-21-glycogen synthase kinase-3β signaling in the functional role of OAT in NSCLC was also revealed. Importantly, in the absence of OAT, the growth and metastasis of tumor lung cancer xenograft was significantly suppressed in the nude mice. Based on our findings, OAT may be a potential novel biomarker for the diagnosis and therapeutic outcome monitoring of NSCLC. Inhibition of OAT may also represent a new therapeutic strategy of NSCLC.

Potentiation of the anticancer effect of doxorubicinin drug-resistant gastric cancer cells by tanshinone IIA

BACKGROUND

Gastric cancer is the fifth commonest cancer and the third cause of cancer-related deaths all over the world. The effectiveness of chemotherapy is still limited by drug resistance in gastric cancer. Tanshinones, abietane diterpenes isolated from the traditional Chinese medicine Danshen (Salvia miltiorrhiza), have exhibited versatile anticancer activities in particular the ability to overcome drug resistance in different cancers.

PURPOSE

The current study aimed to explore the capacity of tanshinone IIA, the most abundant tanshinone found in the plant Danshen, to overcome drug resistance of gastric cancer cells to a commonly used anticancer drug doxorubicin.

STUDY DESIGN

Sensitivity of cell lines to doxorubicin was determined by MTT assay. Doxorubicin resistant gastric cancer cell lines was established by step selection with increasing concentrations of doxorubicin. Cell cycle arrest, apoptosis and doxorubicin efflux were analyzed by flow cytometry. The expression of MRP1 was determined by realtime PCR and western-blot.

RESULTS

Based on the IC₅₀ values of doxorubicin, we identified the doxorubicin-sensitive gastric cancer cell lines SNU-719 and SNU-610 as well as the cell lines relatively resistant to doxorubicin including SNU-638, SNU-668, SNU-216 and SNU-620. We also established two drug-resistant cell lines SNU-719R and SNU-610R. Despite the fact that tanshinone IIA alone showed no cytotoxicity on these gastric cells, we found the potentiation of the anticancer effect of doxorubicin in drug-resistant gastric cancer cells by tanshinone IIA. Furthermore, using doxorubicin-sensitive cell line SNU-719 and doxorubicin-resistant cell lines SNU-719R and SNU-620, we revealed the pivotal roles of MRP1. Its overexpression impaired cell cycle arrest and suppressed apoptosis in the development of both intrinsic and acquired drug resistance in gastric cancer cells to doxorubicin. Importantly, inhibition of MRP1 function enhanced cell cycle arrest, increased apoptosis and induced autophagic cell death which contributed to the capability of tanshinone IIA to potentiate the anticancer effect of doxorubicin in drug-resistant gastric cancer cells.

CONCLUSION

Tanshinone IIA is an interesting agent with potential to treat drug-resistant gastric cancer in combination therapy.

Reactive Oxygen Species and p53 Mediated Activation of p38 and Caspases is Critically Involved in Kaempferol Induced Apoptosis in Colorectal Cancer Cells

Here the molecular mechanisms of Kaempferol were examined in colorectal cancers (CRCs). Kaempferol significantly exerted antiproliferative and cytotoxic effect in HCT116, HCT15, and SW480 cells. Also, Kaempferol increased sub G1 population, G2/M arrest, and the numbers of TUNEL cells in HCT116 colorectal cancer cells. Also, Kaempferol increased the PARP cleavages and activation of caspase-8, -9, and -3, phospho-p38 MAPK, p53, and p21 in HCT116 and HCT15 cells. Of note, Kaempferol generated reactive oxygen species (ROS) (43.7 ± 0.56 vs 25.8 ± 0.43, P < 0.01) in HCT116 cells and reversely ROS inhibitor NAC obstructed the effects of Kaempferol to cleave PARP and caspase-3 and activate phosphorylation of p38 MAPK in HCT116 colorectal cancer cells. Likewise, pancaspase inhibitor z-vad-fmk, p38 MAPK inhibitor SB203580, and p53 depletion blocked PARP and caspase-3 in Kaempferol treated HCT116 colorectal cancer cells. Therefore, these findings provide novel insight that ROS and p53 signalings mediate p38 phosphorylation and caspase activation in Kaempferol stimulated apoptosis in CRCs.

Miltirone-induced apoptosis in cisplatin-resistant lung cancer cells through upregulation of p53 signaling pathways

The active ingredients of natural plants are important sources of antitumor agents. Miltirone is a major effective ingredient in traditional Chinese medicine and it is considered to have anti-infection and immunosuppressive activities. Clinically, it is often used for the treatment of arthritis and immune diseases. The effect of miltirone on cisplatin-resistant lung cancer cells has not been investigated to date. The present study aimed to examine the anticancer effect of miltirone in cisplatin-resistant lung cancer cells. Treatment with miltirone suppressed cell viability and induced apoptosis in HCC827 and A549 platinum-resistant lung cancer cells. It was also revealed that miltirone increased caspase-3/8 activity as well as B-cell lymphoma 2-associated X-protein, apoptosis-inducing factor (AIF), p53 and poly(ADP-ribose) polymerase (PARP) protein expression, whereas it inhibited mitochondrial reactive oxygen species (ROS) generation and matrix metalloproteinase (MMP)-2/9 protein expression in HCC827 and A549 platinum-resistant lung cancer cells. The results of the present study demonstrated that miltirone induces apoptosis in cisplatin-resistant lung cancer cells through ROS-p53, AIF, PARP and MMP2/9 signaling pathways.

Matrine inhibiting pancreatic cells epithelial-mesenchymal transition and invasion through ROS/NF-κB/MMPs pathway

AIMS

Matrine has demonstrated an exclusive anti-tumor effect, including inhibiting cancer cells proliferation and inducing cancer cells apoptosis and autophagy. Whether it can inhibit cancer cells invasion is remain obscure.

MAIN METHODS

The Panc-1 cells were cultured with matrine, NAC and methanol, wound healing assay and transwell invasion assay were applied to detect the migration and invasion ability. The expression of MMP-2 and MMP-9 were assessed, as well as the Epithelial-Mesenchymal Transition marker. Further detect the expression of pP65, total P65, pIκBα, total IκBα, MMP-2, MMP-9 and Panc-1 cells migration and invasion ability to detect whether NF-κB signaling pathway is involved.

KEY FINDINGS

In matrine treated group, the expression of E-cadherin was up-regulated while N-cadherin, Vimentin was down-regulated. In addition, wound healing assay and transwell invasion assay showed that the cells treated with matrine expressed weaker migration and invasion ability, and MMP-2 and MMP-9 was down-regulated in matrine treated group. Further research reveals that the effect of Matrine could decreased the level of intracellular ROS. Furthermore, pP65, pIκBα level was down-regulated in the matrine and NAC group when compared to control group. The panc-1 cells showed less migration and invasion ability, as well as lower MMP-2 and MMP-9 expression in the group treated with NF-κBI along with H₂O₂ when compared with treated with H₂O₂ only.

SIGNIFICANCE

Matrine inhibit pancreatic cancer cells migration and invasion through ROS/NF-κB/MMPs pathway, further validate the anticancer effect of matrine.

Parallel comparative studies on toxicity of quantum dots synthesized and surface engineered with different methods in vitro and in vivo

Quantum dots (QDs) have been considered to be promising probes for biosensing, bioimaging, and diagnosis. However, their toxicity issues caused by heavy metals in QDs remain to be addressed, in particular for their in vivo biomedical applications. In this study, a parallel comparative investigation in vitro and in vivo is presented to disclose the impact of synthetic methods and their following surface modifications on the toxicity of QDs. Cellular assays after exposure to QDs were conducted including cell viability assessment, DNA breakage study in a single cellular level, intracellular reactive oxygen species (ROS) receptor measurement, and transmission electron microscopy to evaluate their toxicity in vitro. Mice experiments after QD administration, including analysis of hemobiological indices, pharmacokinetics, histological examination, and body weight, were further carried out to evaluate their systematic toxicity in vivo. Results show that QDs fabricated by the thermal decomposition approach in organic phase and encapsulated by an amphiphilic polymer (denoted as QDs-1) present the least toxicity in acute damage, compared with those of QDs surface engineered by glutathione-mediated ligand exchange (denoted as QDs-2), and the ones prepared by coprecipitation approach in aqueous phase with mercaptopropionic acid capped (denoted as QDs-3). With the extension of the investigation time of mice respectively injected with QDs, we found that the damage caused by QDs to the organs can be gradually recovered. This parallel comparative investigation suggests that synthetic methods and their resulting surface microenvironment play vital roles in the acute toxicity profiles of QDs. The present study provides updated insights into the fabrication and surface engineering of QDs for their translational applications in theranostics.

Cr(VI) induces cytotoxicity in vitro through activation of ROS-mediated endoplasmic reticulum stress and mitochondrial dysfunction via the PI3K/Akt signaling pathway

The occupational and environmental toxicant hexavalent chromium [Cr(VI)] can cause severe damage to the liver; however, the exact mechanisms associated with its toxicity have not been thoroughly demonstrated. In the present study, the underlying mechanisms of Cr(VI)-induced hepatotoxicity were investigated. Our results showed that Cr(VI) inhibited the growth and proliferation of L-02 hepatocytes. Further study revealed that Cr(VI) significantly induced S-phase cell cycle arrest and apoptosis accompanying with the overproduction of reactive oxygen species (ROS). Cr(VI)-induced apoptosis could be prevented by inhibiting ROS with N-acetyl-l-cysteine (NAC). Additionally, our data showed that Cr(VI)-induced endoplasmic reticulum (ER) stress and mitochondrial dysfunction were concentration- and time-dependent. Moreover, inhibition of C/EBA homologous protein (CHOP) expression by siRNA partially prevented Cr(VI)-induced cell apoptosis, mitochondrial dysfunction and ROS generation. We also found that Cr(VI) treatment inhibited the PI3K/Akt pathway in a concentration- and time-dependent manner. After using IGF-1 (50ng/mL), the specific agonist of the PI3K/AKT signaling pathway, the facilitating effects of Cr(VI) were depressed. This finding demonstrated the relationship between the PI3K/Akt pathway, ER stress and mitochondrial dysfunction. Collectively, these findings indicated that Cr(VI) increased ROS production. Increased ROS production may account for inhibition of the PI3K/Akt pathway and lead to ER stress and mitochondrial dysfunction, which consequently induces apoptosis in L-02 hepatocytes. This study provides novel insights into the molecular mechanisms of Cr(VI)-induced cytotoxicity.

Tricholoma matsutake Aqueous Extract Induces Hepatocellular Carcinoma Cell Apoptosis via Caspase-Dependent Mitochondrial Pathway

Tricholoma matsutake, one of widely accepted functional mushrooms, possesses various pharmacological activities, and its antitumor effect has become an important research point. Our study aims to evaluate the cytotoxicity activities of T. matsutake aqueous extract (TM) in HepG2 and SMMC-7721 cells. In in vitro experiments, TM strikingly reduced cell viability, promoted cell apoptosis, inhibited cell migration ability, induced excessive generation of ROS, and caused caspases cascade and mitochondrial membrane potential dissipation in hepatocellular carcinoma cells. In in vivo experiments, 14-day TM treatment strongly suppressed tumor growth in HepG2 and SMMC-7721-xenografted nude mice without influence on their body weights and liver function. Furthermore, TM increased the levels of cleaved poly-ADP-ribose polymerase (PARP), Bad, and Bax and reduced the expressions of B-cell lymphoma 2 (Bcl-2) in treated cells and tumor tissues. All aforementioned results suggest that caspase-dependent mitochondrial apoptotic pathways are involved in TM-mediated antihepatocellular carcinoma.

Parkin deficiency exacerbate ethanol-induced dopaminergic neurodegeneration by P38 pathway dependent inhibition of autophagy and mitochondrial function

Parkinson's disease (PD) is a neurodegenerative disease characterized by selective degeneration of dopaminergic neurons in the substantia nigra. Parkin (which encoded by Park2), an E3 ubiquitin ligase, is the most frequently mutated gene that has casually been linked to autosomal recessive early onset familial PD. We tested the effect of Park2 on ethanol-induced dopaminergic neurodegeneration in Park2 knockout (KO) transgenic mice after chronic ethanol feeding. Male Park2 wild type (WT) and KO mice (8 weeks old) were fed on a Lieber-DeCarli diet containing 6.6% ethanol for 2 weeks, and compared their responses. We found that knockout of Park2 exacerbates ethanol-induced behavioral impairment as well as dopamine depletion. In the mechanism study, we found that knockout of Park2 increased reactive oxygen species (ROS) production, mitophagy formation, mitochondrial dysfunction, and expression of pro-apoptotic proteins, but decreased expression of pro-autophagic proteins. Knockout of Park2 also increased ethanol-induced activation of p38 mitogen-activated protein kinase. In addition, ROS production, mitophagy formation, mitochondrial dysfunction, and expression of pro-apoptotic proteins were increased, but expression of pro-autophagic proteins were decreased by a treatment of ethanol (100 μM) in Park2 siRNA-transfacted PC12 cells (5 μM). Moreover, the exacerbating effects of Park2 deletion on ethanol-induced ROS generation, mitophagy, mitochondrial dysfunction as well as cell death were reduced by p38 specific inhibitor (SB203580) in in vitro (10 μM) and in vivo 10 mg/kg). Park2 deficiency exacerbates ethanol-induced dopaminergic neuron damage through p38 kinase dependent inhibition of autophagy and mitochondrial function.

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EtOH consumption can induce the ROS formation through activation of p38 MAPK.

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ROS can cause the neurodegeneration through inhibition of the autophagy system.

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Park2 knock down amplifies EtOH-induced decrement of autophagy.

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Park2 knock down amplifies EtOH-induced mitochondrial dysfunction.

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Park2 has a neuroprotective effect against ROS mediated damage of neuron.

Pro-apoptotic and anti-proliferative effects of corn silk extract on human colon cancer cell lines

Corn silk is an economically and nutritionally significant natural product as it represents a staple food for a large proportion of the world population. This study investigated the anticancer activity of corn silk extract in human colon cancer cells and human gastric cancer cells. Following treatment with corn silk extract, certain apoptosis-related events were observed, including inhibition of cell proliferation, loss of mitochondrial membrane potential (ΔΨm), release of Ca2+ and release of cytochrome c from the mitochondria into the cytosol. Our results revealed that corn silk extract inhibited the proliferation of cancer cells and increased the level of apoptosis in a concentration-dependent manner. Western blot analysis revealed that corn silk extract upregulated the levels of Bax, cytochrome c, caspase-3 and caspase-9, but downregulated the levels of B-cell lymphoma 2. These results suggest that corn silk extract may induce apoptosis through the mitochondria-mediated pathway.

Tricholoma matsutake Aqueous Extract Induces Hepatocellular Carcinoma Cell Apoptosis via Caspase-Dependent Mitochondrial Pathway

Tricholoma matsutake, one of widely accepted functional mushrooms, possesses various pharmacological activities, and its antitumor effect has become an important research point. Our study aims to evaluate the cytotoxicity activities of T. matsutake aqueous extract (TM) in HepG2 and SMMC-7721 cells. In in vitro experiments, TM strikingly reduced cell viability, promoted cell apoptosis, inhibited cell migration ability, induced excessive generation of ROS, and caused caspases cascade and mitochondrial membrane potential dissipation in hepatocellular carcinoma cells. In in vivo experiments, 14-day TM treatment strongly suppressed tumor growth in HepG2 and SMMC-7721-xenografted nude mice without influence on their body weights and liver function. Furthermore, TM increased the levels of cleaved poly-ADP-ribose polymerase (PARP), Bad, and Bax and reduced the expressions of B-cell lymphoma 2 (Bcl-2) in treated cells and tumor tissues. All aforementioned results suggest that caspase-dependent mitochondrial apoptotic pathways are involved in TM-mediated antihepatocellular carcinoma.

Anti-inflammatory effect of miltirone on inflammatory bowel disease via TLR4/NF-κB/IQGAP2 signaling pathway

Inflammatory bowel disease (IBD) is characterized by a radical imbalance in the activation of proinflammatory and anti-inflammatory signaling pathways in the gut. This study was conducted to evaluate the anti-inflammation effect of miltirone against IBD in vitro and in vivo, and try to explore the underlying mechanisms. Miltirone could extenuate the loss of colon length and weight caused by TNBS. Additionally, macroscopic scores and DAI were reduced significantly compared with the TNBS group. The levels of TNF-α, IL-1β, IL-6 and IL-8 were increased significantly with the induction by TNBS (100mg/kg) or LPS (0.5mg/mL). Interestingly, miltirone could down-regulate the levels of these increased pro-inflammatory factors in a dose-dependent manner both in vivo and in vitro. The protein and mRNA expressions of TLR4, MyD88, NF-κB p65 were up-regulated by TNBS or LPS stimulation. CRX-526, the TLR4 inhibitor, as well as miltirone could significantly suppress the increased protein and mRNA expressions. Miltirone could up-regulate the descreased IQGAP2 expression induced by LPS. All these revealed that the anti-inflammatory effect of miltirone on IBD may be via regulating TLR4/NF-κB/IQGAP2 signaling pathway. The findings might supply beneficial hints for the drug research to cure the IBD.

miR-30 functions as an oncomiR in gastric cancer cells through regulation of P53-mediated mitochondrial apoptotic pathway

The present study was designed to investigate the role of miR-30 in the development of Gastric cancer (GC). miR-30 expression was increased in GC tissues and cell lines. Downregulation of miR-30 inhibited cell proliferation and promoted apoptosis in HGC-27 cells. Upregulation of miR-30 enhanced the proliferation and inhibited apoptosis. P53 expression was decreased in GC tissues. P53 expression was correlated with miR-30 expression. Downregulation of miR-30 increased P53 expression. Knockdown of P53 inhibited miR-30-inhibitor-induced suppression of cell proliferation and increase of apoptosis. Downregulation of miR-30 increased ROS generation which was inhibited by shP53. miR-30 inhibitors induced a decrease in mitochondrial oxygen consumption, cytoplasmic release of cytochrome c, and activation of Caspase 3 and 9, activating mitochondrial apoptotic pathway. Downregulation of P53 and N-acetyl-cysteine suppressed miR-30 inhibitors-activated mitochondrial dysfunction and apoptotic events. In conclusion, we identified that miR-30 functioned as a potential oncomiR through P53/ROS-mediated regulation of mitochondrial apoptotic pathway.