WTAP promotes proliferation of esophageal squamous cell carcinoma via m6A-dependent epigenetic promoting of PTP4A1.

Esophageal squamous cell carcinoma (ESCC) represents a frequently seen malignancy with high prevalence worldwide. Although current studies have shown that Wilms' tumor 1-associated protein (WTAP), a major part in the methyltransferase complex, is involved in various tumor pathological processes, its specific role in ESCC remains unclear. Therefore, the present work focused on exploring WTAP's function and mechanism in ESCC progression using clinical ESCC specimens, ESCC cells, and mammalian models. Firstly, we proved WTAP was significantly upregulated within ESCC, and WTAP mRNA expression showed a good diagnostic performance for ESCC. Functionally, WTAP positively regulated in-vivo and in-vitro ESCC cells' malignant phenotype through the AKT-mTOR signaling pathway. Meanwhile, WTAP positively regulated the N6-methyladenosine (m6A) modification levels in ESCC cells. Protein tyrosine phase type IVA member 1 (PTP4A1) was confirmed to be the m6A target of WTAP, and WTAP positively regulated the expression of PTP4A1. Further study revealed that PTP4A1 showed high expression within ESCC. Silencing PTP4A1 inhibited the AKT-mTOR signaling pathway to suppress ESCC cells' proliferation. Rescue experiments showed that silencing PTP4A1 partially reversed the WTAP-promoting effect on ESCC cells' proliferation ability. Mechanistically, WTAP regulated PTP4A1 expression to activate the AKT-mTOR pathway, promoting the proliferation of ESCC cells. Our study demonstrated that WTAP regulates the progression of ESCC through the m6A-PTP4A1-AKT-mTOR signaling axis and that WTAP is a potential target for diagnosing and treating ESCC.

Nanostructured SnO2 Thin Films Based on a Convenient Chemical Deposition for Sensitive Detection of Ethanol.

A specific matrix sensor that can operate at low temperatures and has a high sensing response is crucial for monitoring flammable VOC gases. In this study, a nanostructured SnO2 thin film was successfully produced using a suitable chemical deposition method, and its sensing properties were comprehensively analyzed. The SEM images revealed that the thin film of the nanostructured SnO2 is made up of two different sizes of broccoli-like structure nanoparticles. The sensor, which is based on this unique micronano structure, demonstrated a high sensing response (44), low operating temperature (200 °C), and fast response time (6s). Additionally, the nanostructured sensor exhibited excellent resistance to humidity interference and long-term stability. Moreover, DFT is employed to evaluate the electronic properties and to systematically explain the gas sensing mechanism of the nanostructured sensor based on the SnO2 thin film.

Screening of sustainable supply chain performance evaluation indicators based on the ill-conditioned index cycle method.

The establishment of an evaluation indicator system that can accurately assess the sustainability of a supply chain while further enhancing its performance is vital and relevant. Based on the connotation of sustainable supply chains and triple bottom line theory, indicators are initially proposed from economic, environmental, and social dimensions. To increase the explanatory power of the indicator system and decrease information redundancy, the coefficient of variation is applied to identify the indicators with weak interpretation intensity, the ill-conditioned index cycle method is utilized to filter out indicators with redundant information, and data on 100 Chinese listed companies from 2019 to 2021 are used as samples. A performance evaluation indicator system of sustainable supply chains with 16 indicators is ultimately established. The information interpretation strength index and cumulative information contribution rate verify the rationality of the final indicator system. The outcome demonstrates that this screening method can strengthen the representativeness of the indicator system and rapidly reduce redundancy, leading to the better discrimination of the evaluation results. The findings of this study provide an indicator system and a methodological reference for both companies and policymakers and can aid in the transformation of supply chains toward sustainability.

Dexterous electrical-driven soft robots with reconfigurable chiral-lattice foot design.

Dexterous locomotion, such as immediate direction change during fast movement or shape reconfiguration to perform diverse tasks, are essential animal survival strategies which have not been achieved in existing soft robots. Here, we present a kind of small-scale dexterous soft robot, consisting of an active dielectric elastomer artificial muscle and reconfigurable chiral-lattice foot, that enables immediate and reversible forward, backward and circular direction changes during fast movement under single voltage input. Our electric-driven soft robot with the structural design can be combined with smart materials to realize multimodal functions via shape reconfigurations under the external stimulus. We experimentally demonstrate that our dexterous soft robots can reach arbitrary points in a plane, form complex trajectories, or lower the height to pass through a narrow tunnel. The proposed structural design and shape reconfigurability may pave the way for next-generation autonomous soft robots with dexterous locomotion.

A rare case of esophageal anthracosis presenting as a submucosal tumor.

A 62-year-old man with a history of heartburn and regurgitation was referred for the management of a black lesion in the middle esophagus. Our Esophagogastroduodenoscopy (EGD) showed a 13 mm, black protruding lesion located 29cm from the incisor teeth. Endoscopic ultrasonography (EUS) showed a 11.7 mm×7.2 mm hyperechoic mass in the esophageal wall arising in layer 2 and 3. Biopsy of the lesion showed a black and elastic hard appearance. Pathological examination showed chronic inflammatory with coal dust underneath the mucosal epithelium.

ZNF667 facilitates angiogenesis after myocardial ischemia through transcriptional regulation of VASH1 and Wnt signaling pathway.

Zinc finger protein 667 (ZNF667, also referred as Mipu1), a widely expressed KRAB/C2H2­type zinc finger transcription factor, can protect against hypoxic­ischemic myocardial injury. Pro­angiogenesis is regarded as a promising strategy for the treatment of acute myocardial infarction (AMI). However, whether ZNF667 is involved in the angiogenesis following AMI remains to be elucidated. The present study reported that the expression of ZNF667 in CD31­positive endothelial cells (ECs) was upregulated in the heart of AMI mice. Hypoxic challenge (1% oxygen) promoted the mRNA and protein expression of ZNF667 in the human umbilical vein endothelial cells (HUVECs) in a time­dependent manner. Moreover, ZNF667 promoted hypoxia­induced invasion and tube formation of HUVECs. Mechanically, ZNF667 could directly bind to the promoter of anti­angiogenic gene VASH1 and inhibit its expression. Consequently, VASH1 overexpression abolished hypoxic challenge or ZNF667 overexpression­induced invasion and tube formation of HUVECs. Further bioinformatic analyses suggested that overexpression of ZNF667 or knockdown of VASH1­induced differentially expressed genes in HUVECs were greatly enriched in the Wnt signaling pathway (DAAM1, LEF1, RAC2, FRAT1, NFATc2 and WNT5A). Together, these data suggested that ZNF667 facilitates myocardial ischemia­driven angiogenesis through transcriptional repression of VASH1 and regulation of Wnt signaling pathway.

Aberrant HSF1 signaling activation underlies metformin amelioration of myocardial infarction in mice.

Myocardial infarction (MI) is a cardiovascular disease with high morbidity and mortality. Clinically, rehabilitation after massive MI often has a poor prognosis. Therefore, it is necessary to explore the therapeutic methods of myocardial protection after MI. As a first-line treatment for type 2 diabetes, metformin has been found to have a certain protective effect on myocardial tissue. However, its pharmacological mechanism remains unclear. In this study, we investigated key factors that reduced MI with metformin. Through in vivo, in vitro, and in silico analyses, we identified HSF1 as a key target for metformin. HSF1 could up-regulate the transcriptional level of AMPKα2 through transcriptional activation and stimulate the activity of the downstream AMPK/mTOR signaling pathway. Metformin stimulated cardiomyocytes to form stress granules (SGs), and knockdown of HSF1 reversed this process. Furthermore, HSF1 exhibited better in vitro affinity for metformin than AMPK, suggesting that HSF1 may be a more sensitive target for metformin.

Nicorandil alleviates cardiac remodeling and dysfunction post -infarction by up-regulating the nucleolin/autophagy axis.

OBJECTIVE: The present study aimed to investigate whether the drug nicorandil can improve cardiac remodeling after myocardial infarction (MI) and the underlying mechanisms. METHODS: Mouse MI was established by the ligation of the left anterior descending coronary artery and H9C2 cells were cultured to investigate the underlying molecular mechanisms. The degree of myocardial collagen (Col) deposition was evaluated by Masson's staining. The expressions of nucleolin, autophagy and myocardial remodeling-associated genes were measured by Western blotting, qPCR, and immunofluorescence. The apoptosis of myocardial tissue cells and H9C2 cells were detected by TUNEL staining and flow cytometry, respectively. Autophagosomes were observed by transmission electron microscopy. RESULTS: Treatment with nicorandil mitigated left ventricular enlargement, improved the capacity of myocardial diastolic-contractility, decreased cardiomyocyte apoptosis, and inhibited myocardial fibrosis development post-MI. Nicorandil up-regulated the expression of nucleolin, promoted autophagic flux, and decreased the expressions of TGF-ß1 and phosphorylated Smad2/3, while enhanced the expression of BMP-7 and phosphorylated Smad1 in myocardium. Nicorandil decreased apoptosis and promoted autophagic flux in H2O2-treated H9C2 cells. Autophagy inhibitors 3-methyladenine (3MA) and chloroquine diphosphate salt (CDS) alleviated the effects of nicorandil on apoptosis. Knockdown of nucleolin decreased the effects of nicorandil on apoptosis and nicorandil-promoted autophagic flux of cardiomyocytes treated with H2O2. CONCLUSIONS: Treatment with nicorandil alleviated myocardial remodeling post-MI through up-regulating the expression of nucleolin, and subsequently promoting autophagy, followed by regulating TGF-ß/Smad signaling pathway.

Effects of Fe, Mn Individual Doping and (Fe, Mn) Co-Doping on Ferromagnetic Properties of Co2Si Powders.

Magnetic materials are crucial energy materials that are widely used in day-to-day life. Therefore, the development and study of high-performance magnetic materials are of great significance. In this study, the magnetic materials Co66.6Si33.4, Co60.6X6Si33.4 (X = Fe, Mn), and Co60.6Fe3Mn3Si33.4 were prepared via the ball milling and sintering processes. Their crystal structures, electrical conductivity, and magnetic properties were investigated via the X-ray diffraction analysis and by using a resistivity tester, vibrating sample magnetometer, and vector network analyser. The X-ray diffraction analysis revealed that a single phase of Co66.6Si33.4 and its doped alloy powders were successfully obtained. The electrical conductivities of Mn6Co60.6Si33.4 and Fe3Mn3Co60.6Si33.4 were measured using a resistivity tester. The results indicate that Mn doping and Fe and Mn Co-doping enhanced the electrical conductivity of Co66.6Si33.4. The magnetic properties of Co66.6Si33.4 were determined using a vibrating sample magnetometer. We observed that the magnetic properties were enhanced after doping. Co60.6Fe3Mn3Si33.4 exhibited excellent magnetic properties. Further, its permeability was determined using a vector network analyser. At a low frequency, the u' and u" values of Co60.6Fe6Si33.4 and Co60.6Fe3Mn3Si33.4 were enhanced; whereas, at a high frequency, after doping, the u' and u" values changed only slightly. This study can be used as a basis for future studies on magnetic functional materials.

Muscle-fiber array inspired, multiple-mode, pneumatic artificial muscles through planar design and one-step rolling fabrication.

Advances in development of artificial muscles have enabled creation of soft robots with biological dexterity and self-adaption in unstructured environments; however, production of scalable artificial muscles with multiple-mode actuations remains elusive. Inspired by muscle-fiber arrays in muscular hydrostats, we present a class of versatile artificial muscles called MAIPAMs (muscle-fiber array inspired pneumatic artificial muscles), capable of multiple-mode actuations (such as parallel elongation-bending-spiraling actuations, 10 parallel bending actuations and cascaded elongation-bending-spiraling actuations). Our MAIPAMs consist of active 3D elastomer-balloon arrays reinforced by a passive elastomer membrane, achieved through a planar design and one-step rolling fabrication approach. We introduce prototypical designs for the MAIPAMs and demonstrate their muscle-mimic structures and versatility, as well as their scalable ability to integrate flexible but non-stretchable layers for contraction and twisting actuation modes and compliant electrodes for self-sensing. We further demonstrate that this class of artificial muscles shows potential for versatile robotic applications, such as carrying a camera for recording videos, gripping or manipulating objects, and climbing a pipe-line.

Human Telomerase Reverse Transcriptase as a Therapeutic Target of Dihydroartemisinin for Esophageal Squamous Cancer.

Objective: To elucidate the oncogenic role of human telomerase reverse transcriptase (hTERT) in esophageal squamous cancer and unravel the therapeutic role and molecular mechanism of dihydroartemisinin (DHA) by targeting hTERT. Methods: The expression of hTERT in esophageal squamous cancer and the patients prognosis were analyzed by bioinformatic analysis from TCGA database, and further validated with esophageal squamous cancer tissues in our cohort. The Cell Counting Kit-8 (CCK8) and colony formation assay were used to evaluate the proliferation of esophageal squamous cancer cell lines (Eca109, KYSE150, and TE1) after hTERT overexpression or treated with indicated concentrations of DHA. Transwell migration assay and scratch assay were employed to determine the migration abilities of cancer cells. Fluorescence microscopy and flow cytometry were conducted to measure the intracellular reactive oxygen species (ROS) levels in cancer cells after treated with DHA. Moreover, RT-PCR and Western blot were performed to test the alteration of associated genes on mRNA and protein level in DHA treated esophageal squamous cancer cell lines, respectively. Furthermore, tumor-bearing nude mice were employed to evaluate the anticancer effect of DHA in vivo. Results: We found that hTERT was significantly upregulated in esophageal squamous cancer both from TCGA database and our cohort also. Overexpression of hTERT evidently promoted the proliferation and migration of esophageal squamous cancer cells in vitro. Moreover, DHA could significantly inhibit the proliferation and migration of esophageal cancer cell lines Eca109, KYSE150, and TE1 in vitro, and significantly down-regulate the expression of hTERT on both mRNA and protein level in a time- and dose-dependent manner as well. Further studies showed that DHA could induce intracellular ROS production in esophageal cancer cells and down-regulate SP1 expression, a transcription factor that bound to the promoter region of hTERT gene. Moreover, overexpression of SP1 evidently promoted the proliferation and migration of Eca109 and TE1 cells. Intriguingly, rescue experiments showed that inhibiting ROS by NAC alleviated the downregulation of SP1 and hTERT in cells treated with DHA. Furthermore, overexpression of SP1 or hTERT could attenuate the inhibition effect of DHA on the proliferation and migration of Eca109 cells. In tumor-bearing nude mice model, DHA significantly inhibited the growth of esophageal squamous cancer xenografts, and downregulated the expression of SP1 and hTERT protein, while no side effects were observed from heart, kidney, liver, and lung tissues by HE stain. Conclusion: hTERT plays an oncogenic role in esophageal squamous cancer and might be a therapeutic target of DHA through regulating ROS/SP1 pathway.

The M6A methyltransferase METTL3 regulates proliferation in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal human cancers with a lower 5-year survival rate. N6-methyladenosine (m6A) methylation, an important epigenetic modification, has been reported to associate with physiological and pathological processes of cancers. However, its role in ESCC remains unclear. In this work, we found that the m6A levels were elevated in ESCC cancer tissues and ESCC cells. The PPI network demonstrated that METTL3, METTL14, WTAP, RBM15, and KIAA1429 were all significantly associated with each other. Moreover, we found a significant upregulation of METTL3 mRNA and protein amounts in ESCC tissues. The METTL3 mRNA expression level of tissues had associations with ESCC differentiation extent and sex (p < 0.05). The METTL3 mRNA expression level of tissues, sensitivity for diagnosing ESCC was 75.00%, specificity was 72.06% and area under the ROC curve was 0.8030. Depletion of METTL3 markedly diminished m6A levels in human ESCC cell lines and METTL3 overexpression restored the reduction in m6A levels. These results suggested that METTL3 is the primary enzyme that modulates m6A methylation and a critical regulatory factor in ESCC. Additionally, METTL3 knockdown significantly suppressed the ESCC cell proliferation, while METTL3 overexpression markedly promoted ESCC cell proliferation both in cell and animal models. These results demonstrated that METTL3 promotes ESCC development. Furthermore, METTL3 may modulate the cell cycle of ESCC cells through a p21-dependent pattern. METTL3-guided m6A modification may contribute to the progression of ESCC via the p21-axis. Our study is the first investigation to report that METTL3-mediated m6A methylation plays a crucial role in ESCC oncogenesis and highlights that METTL3 might be a potential biomarker and therapeutic target for ESCC patients.

MicroRNA-449a inhibits cell proliferation and migration by regulating mutant p53 in MDA-MB-468 cells.

The present study aimed to investigate the role of microRNA (miR)-449a in the proliferation, migration and apoptosis of MDA-MB-468 breast cancer cells and examine the association between miR-449a and mutant p53 in these cells. Cell proliferation, migration and invasion were examined using a crystal violet staining assay, wound healing scratch assay and Transwell assay, respectively. The expression level of miR-449a and p53 was detected by reverse transcription-quantitative PCR or western blotting. The results indicated that knockdown of mutant p53 suppressed the proliferation and migration of MDA-MB-468 cells by inhibiting the PI3K/AKT/mTOR signaling pathway. In addition, miR-449a suppressed proliferation and migration via downregulation of mutant p53 expression in MDA-MB-468 cells. Therefore, miR-449a may function as a tumor suppressor by regulating p53 expression in breast cancer cells, which may have potential implications in the treatment of patients with triple-negative breast cancer carrying mutant p53.

Increased HSF1 Promotes Infiltration and Metastasis in Cervical Cancer via Enhancing MTDH-VEGF-C Expression.

PURPOSE: To explore the molecular mechanism of promoting cervical cancer by HSF1 in vivo and in vitro. METHODS: The expression of HSF1 in 110 paraffin-embedded cervical cancer sections of different grades was examined via immunohistochemistry analyses. Expression of HSF1 downstream targets Metadherin (MTDH), VEGF-C and CD31 were studied using immunohistochemistry analyses. HSF1 transcriptional activity in the MTDH promoter region was detected by EMSA, CHIP and luciferase. Cell proliferation and clonality were detected by MTT and clonal formation assay. Cell migration and invasion ability were investigated by scratch analysis and transwell assay. HSF1-mediated tumorigenesis in vivo was examined in xenograft models. RESULTS: HSF1 expression of cervical cancer cell line was increased compared to normal human cervical tissues. HSF1 enhanced the expression of MTDH, VEGF-C and CD31. HSF1 can combine with MTDH promoter to promote the expression of MTDH. HSF1 enhanced HeLa cell proliferation and clone formation. Furthermore, HSF1 increased HeLa cells migration and invasion in vitro. In the transplanted tumor model, HSF1 inhibited tumor growth in vivo after interference, and reduced the expression of MTDH, VEGF-C and CD31. DISCUSSION: HSF1 can promote the proliferation, metastasis and invasion of cervical cancer.

New insight into the joint significance of dietary jujube polysaccharides and 6-gingerol in antioxidant and antitumor activities.

The combinatorial use of dietary jujube (Ziziphus jujuba) and ginger play a critical role in traditional Chinese medicines, folk medicine and dietary therapy. Joint effects were investigated from the viewpoint of the antioxidant (scavenging DPPH˙) and antitumor activities (against SW620 cells) of jujube polysaccharides and ginger 6-gingerol (G6G) alone and in combination. Jujube polysaccharides were extracted, purified, and characterized, and then their inhibiting and apoptotic effects alone and in combination with G6G were evaluated by the cytological tests, including Cell Counting Kit-8, colony-forming, Annexin V-FITC and propidium iodide, TdT-mediated dUTP nick end labeling (TUNEL) staining, and cell cycle assays. Results showed that the purified polysaccharide fraction (ZJPs-II) with average molecular weight of 115 kDa consisted of arabinose, rhamnose, glucose, xylose, and galactose. ZJPs-II and G6G alone dose-dependently scavenged DPPH˙ and inhibited the proliferation of SW620 cells, while their combination showed synergistic interactions (all combination index < 1). The studies further demonstrated that ZJPs-II and G6G alone reduced the cell colony-formation, induced apoptosis and arrested the cell-cycle at G2/M phase, while their combination achieved better effects and significantly arrested the growth at the G0/G1 phase. Collectively, our findings suggest enhancing the intake of jujube polysaccharides and G6G in a combinatorial approach for maintaining health and preventing cancer.

HSF1 functions as a key defender against palmitic acid-induced ferroptosis in cardiomyocytes.

Palmitic acid (PA)-induced myocardial injury is considered a critical contributor to the development of obesity and type 2 diabetes mellitus (T2DM)-related cardiomyopathy. However, the underlying mechanism has not been fully understood. Here, we demonstrated that PA induced the cell death of H9c2 cardiomyoblasts in a dose- and time-dependent manner, while different ferroptosis inhibitors significantly abrogated the cell death of H9c2 cardiomyoblasts and primary neonatal rat cardiomyocytes exposed to PA. Mechanistically, PA decreased the protein expression levels of both heat shock factor 1 (HSF1) and glutathione peroxidase 4 (GPX4) in a dose- and time-dependent manner, which were restored by different ferroptosis inhibitors. Overexpression of HSF1 not only alleviated PA-induced cell death and lipid peroxidation but also improved disturbed iron homeostasis by regulating the transcription of iron metabolism-related genes (e.g., Fth1, Tfrc, Slc40a1). Additionally, PA-blocked GPX4 protein expression was evidently restored by HSF1 overexpression. Inhibition of endoplasmic reticulum (ER) stress rather than autophagy contributed to HSF1-mediated GPX4 expression. Moreover, GPX4 overexpression protected against PA-induced ferroptosis, whereas knockdown of GPX4 reversed the anti-ferroptotic effect of HSF1. Consistent with the in vitro findings, PA-challenged Hsf1-/- mice exhibited more serious ferroptosis, increased Slc40a1 and Fth1 mRNA expression, decreased GPX4 and TFRC expression and enhanced ER stress in the heart compared with Hsf1+/+ mice. Altogether, HSF1 may function as a key defender against PA-induced ferroptosis in cardiomyocytes by maintaining cellular iron homeostasis and GPX4 expression.

Metformin protects against ischaemic myocardial injury by alleviating autophagy-ROS-NLRP3-mediated inflammatory response in macrophages.

Myocardial ischaemia is usually accompanied by inflammatory response which plays a critical role in the myocardial healing and scar formation, while persistent inflammatory response contributes greatly to the myocardial remodeling and consequent heart failure. Metformin (Met), a widely used hypoglycemic drug, has increasingly been shown to exert remarkable cardioprotective effect on ischaemic myocardial injury such as acute myocardial infarction (AMI). However, the underlying mechanisms are still far from being fully understood. In this study, a mouse model of AMI was established through ligating the left anterior descending coronary artery (LAD), 100 mg/kg Met was given immediately after operation once daily for 3 days. It was demonstrated that Met effectively improved the cardiac haemodynamics (LVSP, LVEDP, +dp/dt, -dp/dt), diminished the infarct size, alleviated the disarrangement of myocardial cells and reduced the infiltration of inflammatory cells (macrophages, neutrophils and lymphocytes) in the heart of AMI mice. Mechanistically, Met decreased the expression of NLRP3 and enhanced the accumulation of LC3 puncta in F4/80-positive macrophages in the heart of AMI mice. Single cell suspension of cardiac macrophages was prepared from AMI mice and exhibited increased NLRP3 mRNA and protein expression. In contrast, Met decreased the expression of NLRP3 and p62, whereas increased the ratio of LC3II/LC3I. Additionally, both conditioned medium from H9c2 cardiomyocytes exposed to hydrogen peroxide (H9c2-H2O2-CM) and combination of mtDNA and ATP (mtDNA-ATP) increased the expression of NLRP3 and cleaved caspase-1 (p10) as well as intracellular ROS production in RAW264.7 macrophages, which were abrogated by Met treatment. Strikingly, chloroquine (CQ), 3-methyladenine (3-MA) and knockdown of autophagy-related gene (Atg5) abrogated the inhibitory effects of Met on H9c2-H2O2-CM and mtDNA-ATP-induced NLRP3 expression, release of IL-1ß and IL-18 as well as ROS production in RAW264.7 macrophages. Collectively, these findings suggest that Met protects against ischaemic myocardial injury through alleviating autophagy-ROS-NLRP3 axis-mediated inflammatory response in macrophages.

Autophagy-dependent cell cycle arrest in esophageal cancer cells exposed to dihydroartemisinin.

BACKGROUND: Dihydroartemisinin (DHA), a derivate of artemisinin, is an effective antimalarial agent. DHA has been shown to exert anticancer activities to numerous cancer cells in the past few years, while the exact molecular mechanisms remain to be elucidated, especially in esophageal cancer. METHODS: Crystal violet assay was conducted to determine the cell viability of human esophageal cancer cell line Eca109 treated with DHA. Tumor-bearing nude mice were employed to evaluate the anticancer effect of DHA in vivo. Soft agar and crystal violet assays were used to measure the tumorigenicity of Eca109 cells. Flow cytometry was performed to evaluate ROS or cell cycle distribution. GFP-LC3 plasmids were delivered into Eca109 cells to visualize autophagy induced by DHA under a fluorescence microscope. The mRNA and protein levels of each gene were tested by qRT-PCR and western blot, respectively. RESULTS: Our results proved that DHA significantly reduced the viability of Eca109 cells in a dose- and time-dependent manner. Further investigation showed that DHA evidently induced cell cycle arrest at the G2/M phase in Eca109 cells. Mechanistically, DHA induced intracellular ROS generation and autophagy in Eca109 cells, while blocking ROS by an antioxidant NAC obviously inhibited autophagy. Furthermore, we found that telomere shelterin component TRF2 was down-regulated in Eca109 cells exposed to DHA through autophagy-dependent degradation, which could be rescued after autophagy was blocked by ROS inhibition. Moreover, the DNA damage response (DDR) was induced obviously in DHA treated cells. To further explore whether ROS or autophagy played a vital role in DHA induced cell cycle arrest, the cell cycle distribution of Eca109 cells was evaluated after ROS or autophagy blocking, and the results showed that autophagy, but not ROS, was essential for cell cycle arrest in DHA treated cells. CONCLUSION: Taken together, DHA showed anticancer effect on esophageal cancer cells through autophagy-dependent cell cycle arrest at the G2/M phase, which unveiled a novel mechanism of DHA as a chemotherapeutic agent, and the degradation of TRF2 followed by DDR might be responsible for this cell phenotype.

Systematic prediction of key genes for ovarian cancer by co-expression network analysis.

Ovarian cancer (OC) is the most lethal gynaecological malignancy, characterized by high recurrence and mortality. However, the mechanisms of its pathogenesis remain largely unknown, hindering the investigation of the functional roles. This study sought to identify key hub genes that may serve as biomarkers correlated with prognosis. Here, we conduct an integrated analysis using the weighted gene co-expression network analysis (WGCNA) to explore the clinically significant gene sets and identify candidate hub genes associated with OC clinical phenotypes. The gene expression profiles were obtained from the MERAV database. Validations of candidate hub genes were performed with RNASeqV2 data and the corresponding clinical information available from The Cancer Genome Atlas (TCGA) database. In addition, we examined the candidate genes in ovarian cancer cells. Totally, 19 modules were identified and 26 hub genes were extracted from the most significant module (R2  = .53) in clinical stages. Through the validation of TCGA data, we found that five hub genes (COL1A1, DCN, LUM, POSTN and THBS2) predicted poor prognosis. Receiver operating characteristic (ROC) curves demonstrated that these five genes exhibited diagnostic efficiency for early-stage and advanced-stage cancer. The protein expression of these five genes in tumour tissues was significantly higher than that in normal tissues. Besides, the expression of COL1A1 was associated with the TAX resistance of tumours and could be affected by the autophagy level in OC cell line. In conclusion, our findings identified five genes could serve as biomarkers related to the prognosis of OC and may be helpful for revealing pathogenic mechanism and developing further research.