Costunolide Inhibits the Growth of OAW42-A Multidrug-Resistant Human Ovarian Cancer Cells by Activating Apoptotic and Autophagic Pathways, Production of Reactive Oxygen Species (ROS), Cleaved Caspase-3 and Cleaved Caspase-9

Investigation of Molecular Mechanisms Involved in Sensitivity to the Anti-Cancer Activity of Costunolide in Breast Cancer Cells

Costunolide (CTL), an active compound isolated from Saussurea lappa Clarke and Laurus nobilis L, has been shown to induce apoptosis via reactive oxygen species (ROS) generation in various types of cancer cells. However, details of molecular mechanisms underlying the difference in sensitivity of cancer cells to CTL are still largely unknown. Here, we tested the effect of CTL on the viability of breast cancer cells and found that CTL had a more efficient cytotoxic effect against SK-BR-3 cells than MCF-7 cells. Mechanically, ROS levels were significantly increased upon CTL treatment only in SK-BR-3 cells, which leads to lysosomal membrane permeabilization (LMP) and cathepsin D release, and subsequent activation of the mitochondrial-dependent intrinsic apoptotic pathway by inducing mitochondrial outer membrane permeabilization (MOMP). In contrast, treatment of MCF-7 cells with CTL activated PINK1/Parkin-dependent mitophagy to remove damaged mitochondria, which prevented the elevation of ROS levels, thereby contributing to their reduced sensitivity to CTL. These results suggest that CTL is a potent anti-cancer agent, and its combination with the inhibition of mitophagy could be an effective method for treating breast cancer cells that are less sensitive to CTL.

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.

Costunolide-Induced Apoptosis via Promoting the Reactive Oxygen Species and Inhibiting AKT/GSK3β Pathway and Activating Autophagy in Gastric Cancer

Objective: Costunolide (Cos) is a sesquiterpene lactone extracted from chicory. Although it possesses anti-tumor effects, the underlying molecular mechanism against gastric cancer cells remains unclear. This study aimed to explore the effect and potential mechanism of Cos on gastric cancer.

Methods: The effect of Cos on HGC-27 and SNU-1 proliferation was detected by CCK-8 and clone formation assay. The changes in cell apoptosis were determined using Hoechst 33258 and tunel staining. The morphology of autophagy was analyzed by autophagosomes with the electron microscope and LC3-immunofluorescence with the confocal microscope. The related protein levels of the cell cycle, apoptosis, autophagy and AKT/GSK3β pathway were determined by Western blot. The anti-tumor activity of Cos was evaluated by subcutaneously xenotransplanting HGC-27 into Balb/c nude mice. The Ki67 and P-AKT levels were examined by immunohistochemistry.

Results: Cos significantly inhibited HGC-27 and SNU-1 growth and induced cell cycle arrest in the G2/M phase. Cos activated intrinsic apoptosis and autophagy through promoting cellular reactive oxygen species (ROS) levels and inhibiting the ROS-AKT/GSK3β signaling pathway. Moreover, preincubating gastric carcinoma cells with 3-methyladenine (3-MA), a cell-autophagy inhibitor, significantly alleviated the effects of Cos in inducing cell apoptosis.

Conclusion: Cos induced apoptosis of gastric carcinoma cells via promoting ROS and inhibiting AKT/GSK3β pathway and activating pro-death cell autophagy, which may be an effective strategy to treat gastric cancer.

Establishment and validation of five autophagy-related signatures for predicting survival and immune microenvironment in glioma

BACKGROUND

Gliomas, especially Glioblastoma multiforme, are the most frequent type of primary tumors in central nervous system. Increasing researches have revealed the relationship between autophagy and tumor, while the molecular mechanism of autophagy in glioma is still rarely reported.

OBJECTIVE

Our research aims to conform the autophagy-related genes (ARGs) implicated in the development and progression of glioma and improve our understanding of autophagy in glioma.

METHODS

20 candidate ARGs were screened through the protein-protein interaction network. We also downloaded the publicly accessible glioma data for 665 individuals from TCGA and 970 individuals from CGGA with RNA sequences and clinicopathological information. Subsequently, univariate and multivariate Cox regression analysis identified 5 key ARGs among the 20 candidate genes as key prognostic genes for survival, GSEA and immune response analysis.

RESULTS

ATG5, BCL2L1, CASP3, CASP8, GAPDH were identified as key ARGs in our research. Further studies showed that the high-risk population was linked to a dismal prognosis and suggested an immune-inhibitory microenvironment. GSEA results demonstrated that high risk population was closely related to DNA repair, hypoxia pathways, implicated in immunosuppression and carcinogenesis. Through CMap, we finally identified 14 candidate drugs for the ARG high risk population.

CONCLUSIONS

This study established and verified an ARG risk model, which can serve as an independent predictor for prognosis, reflect on the strength of the immune response and predict the potential drugs in glioma. Our findings offer new understandings of ARG molecular mechanism and promising therapeutic targets for glioma treatment.

Costunolide Induces Apoptosis via the Reactive Oxygen Species and Protein Kinase B Pathway in Oral Cancer Cells

Oral cancer (OC) has been attracted research attention in recent years as result of its high morbidity and mortality. Costunolide (CTD) possesses potential anticancer and bioactive abilities that have been confirmed in several types of cancers. However, its effects on oral cancer remain unclear. This study investigated the potential anticancer ability and underlying mechanisms of CTD in OC in vivo and in vitro. Cell viability and anchorage-independent colony formation assays were performed to examine the antigrowth effects of CTD on OC cells; assessments for migration and invasion of OC cells were conducted by transwell; Cell cycle and apoptosis were investigated by flow cytometry and verified by immunoblotting. The results revealed that CTD suppressed the proliferation, migration and invasion of oral cancer cells effectively and induced cell cycle arrest and apoptosis; regarding the mechanism, CTD bound to AKT directly by binding assay and repressed AKT activities through kinase assay, which thereby downregulating the downstream of AKT. Furthermore, CTD remarkably promotes the generation of reactive oxygen species by flow cytometry assay, leading to cell apoptosis. Notably, CTD strongly suppresses cell-derived xenograft OC tumor growth in an in vivo mouse model. In conclusion, our results suggested that costunolide might prevent progression of OC and promise to be a novel AKT inhibitor.

Undifferentiated Pleomorphic Sarcoma With Hyaline Globules (Thanatosomes)

Hyaline globules (HGs) or thanatosomes belong to a well-defined microscopic phenomenon common to any cell type, representing eosinophilic and round-shaped intracytoplasmic inclusions as a result of altered cellular metabolism. We experienced a case of undifferentiated pleomorphic sarcoma (UPS) of the left thigh, immunoreactive diffusely for CD99 and p16INK4a and focally for alpha-smooth muscle actin. HGs were multifocally clustered in the cytoplasm of the tumor cells. An ultrastructural study using a formalin-fixed, paraffin-embedded block was performed to visualize HGs in the UPS cells. Light microscopically, multifocally clustered HGs were PAS-positive with diastase-resistance and fuchsinophilic in Masson's trichrome staining. HGs were immunoreactive for cleaved caspase-3, but negative for ubiquitin. Ultrastructurally, apoptotic tumor cells contained clusters of small-sized electron-dense globules. Granular material was often deposited in the globule matrix. The formation of the HGs is supposedly related to an apoptotic process of the tumor cells. Though a nonspecific and minor microscopic finding, HGs in soft tissue sarcomas may represent a useful histologic marker of enhanced cell turnover and/or ischemic injury. This is the third report describing HGs in UPS.

Triptolide inhibits JAK2/STAT3 signaling and induces lethal autophagy through ROS generation in cisplatin‑resistant SKOV3/DDP ovarian cancer cells

Advanced and recurrent ovarian cancer has a poor prognosis and is frequently resistant to numerous therapeutics; thus, safe and effective drugs are needed to combat this disease. Previous studies have demonstrated that triptolide (TPL) exhibits anticancer and sensitization effects against cisplatin (DDP)-resistant ovarian cancer both in vitro and in vivo by inducing apoptosis; however, the involvement of autophagy induced by TPL in resistant ovarian carcinoma remains unclear. In the present study, the results revealed that TPL induced autophagy to facilitate SKOV3/DDP ovarian cancer cell death. The xenograft experiment revealed that the autophagy inhibitor CQ significantly reduced TPL-mediated chemosensitization and tumor growth inhibition. Mechanically, TPL-induced autophagy in SKOV3/DDP cells was associated with the induction of ROS generation and inhibition of the Janus kinase 2 (JAK2)/signal transducer and activator of transcription-3 (STAT3) pathway. The inhibitory effect of TPL on the JAK2/STAT3 pathway could be restored in the presence of the antioxidant NAC. Furthermore, it was further determined that TPL disrupted the interaction between Mcl-1 and Beclin1, which was prevented by the JAK2/STAT3 signaling activator IL-6. Overall, the present results revealed a novel molecular mechanism whereby TPL induced lethal autophagy through the ROS-JAK2/STAT3 signaling cascade in SKOV3/DDP cells. The present study has provided the groundwork for future application of TPL in the treatment of ovarian cancer.

Thymoquinone and Costunolide Induce Apoptosis of Both Proliferative and Doxorubicin-Induced-Senescent Colon and Breast Cancer Cells

Doxorubicin (Dox) induces senescence in numerous cancer cell types, but these senescent cancer cells relapse again if they are not eliminated. On this principle, we investigated the apoptotic effect of thymoquinone (TQ), the active ingredient of Nigella sativa seeds and costunolide (COS), the active ingredient of Costus speciosus, on the senescent colon (Sen-HCT116) and senescent breast (Sen-MCF7) cancer cell lines in reference to their corresponding proliferative cells to rapidly eliminate the senescent cancer cells. The senescence markers of Sen-HCT116 and Sen-MCF7 were determined by a significant decrease in bromodeoxyuridine (BrdU) incorporation and significant increases in SA-β-gal, p53, and p21 levels. Then proliferative, Sen-HCT116, and Sen-MCF7 cells were subjected to either TQ (50 µM) or COS (30 µM), the Bcl2-associated X protein (Bax), B-cell lymphoma 2 (Bcl2), caspase 3 mRNA expression and its activity were established. Results revealed that TQ significantly increased the Bax/Bcl2 ratio in HCT116 + Dox5 + TQ, MCF7 + TQ, and MCF7 + Dox5 + TQ compared with their corresponding controls. COS significantly increased the Bax/Bcl2 ratio in HCT116 + Dox5 + TQ and MCF7 + Dox5 + TQ compared with their related controls. Also, TQ and COS were significantly increased caspase 3 activity and cell proliferation of Sen-HCT116 and Sen-MCF7. The data revealed a higher sensitivity of senescent cells to TQ or COS than their corresponding proliferative cells.

Antitumor activity and mechanism of costunolide and dehydrocostus lactone: Two natural sesquiterpene lactones from the Asteraceae family

Costunolide (COS) and dehydrocostus lactone (DEH) are two natural sesquiterpene lactones with potential antitcancer activity against a range of cancer cell types both in vitro and in vivo, particularly for breast cancer and leukemia. There are many researches that have been taken to characterize these pathways and to reveal their anticancer mechanisms of action of COS and DEH. However, while there is a great deal of evidence detailing the effects of COS and DEH on considerable signaling pathways and cellular functions, a global view of their mechanism of action remains elusive. This review systematically summarizes the antitumor activity and mechanism of COS and DEH in the recent reports, and discusses the effect of the key active part (α-methylene-γ-butyrolactone) of COS and DEH against cancer. Moreover, we also discuss the antineoplastic activity of COS and DEH derivatives to improve the cytotoxicity and safety index. We believe this review can provide a systemic reference to develop COS and DEH as anticancer agents.

Costunolide-A Bioactive Sesquiterpene Lactone with Diverse Therapeutic Potential

Sesquiterpene lactones constitute a major class of bioactive natural products. One of the naturally occurring sesquiterpene lactones is costunolide, which has been extensively investigated for a wide range of biological activities. Multiple lines of preclinical studies have reported that the compound possesses antioxidative, anti-inflammatory, antiallergic, bone remodeling, neuroprotective, hair growth promoting, anticancer, and antidiabetic properties. Many of these bioactivities are supported by mechanistic details, such as the modulation of various intracellular signaling pathways involved in precipitating tissue inflammation, tumor growth and progression, bone loss, and neurodegeneration. The key molecular targets of costunolide include, but are not limited to, intracellular kinases, such as mitogen-activated protein kinases, Akt kinase, telomerase, cyclins and cyclin-dependent kinases, and redox-regulated transcription factors, such as nuclear factor-kappaB, signal transducer and activator of transcription, activator protein-1. The compound also diminished the production and/expression of proinflammatory mediators, such as cyclooxygenase-2, inducible nitric oxide synthase, nitric oxide, prostaglandins, and cytokines. This review provides an overview of the therapeutic potential of costunolide in the management of various diseases and their underlying mechanisms.

Screening of Crude Drugs Used in Japanese Kampo Formulas for Autophagy-Mediated Cell Survival of the Human Hepatocellular Carcinoma Cell Line

Background: Autophagy is a catabolic process through which dysfunctional proteins and organelles are degraded, and that is associated with the proliferation of cancer cells. The aim of this study was to screen approximately 130 kinds of crude drugs used in Japanese Kampo formulas to identify crude drugs that would regulate the proliferation through autophagy of human hepatocellular carcinoma HepG2 cells. Methods: Extracts of each crude drug were prepared using methanol. Protein levels were determined using Western blotting. Cell viability was measured by MTT assay. Results: Among the 130 crude extracts, 24 of them increased LC3-II expression. Among these, Goboshi (burdock fruit), Soboku (sappan wood), Mokko (saussurea root), Rengyo (forsythia fruit), and Hikai (dioscorea) notably suppressed the proliferation of HepG2 cells and increased p62 expression levels, which suggested that these five extracts downregulate the autophagic activity resulting in the accumulation of p62. On the other hand, Hishinomi (water chestnut), Biwayo (loquat leaf), and Binroji (areca) induced cell growth and decreased or were uninvolved with p62 expression levels, which implied that these three extracts might induce autophagy modulators for cell growth. Conclusions: The results suggest that the compounds contained in the crude drugs selected for this study could control cell viability by regulating autophagic activity in HepG2 cells. The isolation and identification of the active compounds in these drugs might lead to the development of agents for autophagy research and cancer chemoprevention.