hsa_circ_0000264 promotes tumor progression via the hsa-let-7b-5p/HMGA2 axis in head and neck squamous cell carcinoma.

OBJECTIVE: Circular RNAs (CircRNAs) are involved in various tumors. However, their role in head and neck squamous cell carcinoma (HNSCC) is unknown. CircRNA sequencing data showed that hsa_circ_0000264 is significantly upregulated in HNSCC tissues. In this study, we aimed to investigate the role of hsa_circ_0000264 in HNSCC and elucidate its underlying regulation mechanism. MATERIALS AND METHODS: RNase R treatment was performed to confirm the loop structure of hsa_circ_0000264. Fluorescence in situ hybridization was performed to show the subcellular localization of hsa_circ_0000264. We then performed wound healing assay, Transwell assay, Western blot, and in vivo experiments to determine the effect of alterations in hsa_circ_0000264 expression. We performed RNA pull-down and dual luciferase reporter assay to identify and confirm the binding sites in RNAs. RESULTS: hsa_circ_0000264 was upregulated in HNSCC tissues and cells, and its loop structure was confirmed. Knockdown of hsa_circ_0000264 inhibited the migration, invasion, and epithelial-to-mesenchymal transition of HNSCC cells in vivo and in vitro. Mechanistically, hsa_circ_000026 upregulation can upregulate the expression of high mobility group AT-hook 2 (HMGA2) by sponging hsa-let-7b-5p, which in turn promotes HNSCC progression. CONCLUSION: Our results showed that hsa_circ_0000264 promotes HNSCC progression via the hsa-let-7b-5p/HMGA2 axis, and hsa_circ_0000264 can serve as a potential target for HNSCC treatment.

CD73 facilitates invadopodia formation and boosts malignancy of head and neck squamous cell carcinoma via the MAPK signaling pathway.

Elevated adenosine generated by CD73 (ecto-5'-nucleotidase; NT5E) could boost immunosuppressive responses and promote immune evasion in the tumor microenvironment. However, despite the immune response, CD73 could also promote tumor progression in a variety of cancers, and the nonimmunologic role and corresponding molecular mechanism of CD73 involved in head and neck squamous cell carcinoma (HNSCC) progression are not well characterized. Here, we demonstrated that CD73/NT5E is overexpressed in HNSCC tissues and predicts poor prognosis. Suppression of CD73 inhibited the proliferation, migration, and invasion of HNSCC cell lines (CAL27 and HN4) in vitro and in vivo. Gene set variation analysis (GSVA) and gene set enrichment analysis (GSEA) predicted that CD73 may be involved in invadopodia formation and MAPK signaling activation. As expected, knockdown of CD73 inhibited the MAPK signaling pathway, and the suppressive effect of CD73 knockdown on proliferation, migration, invasion, and invadopodia formation was reversed by a MAPK signaling activator. Our results suggest that CD73 could promote the proliferation, migration, invasion, and invadopodia formation of HNSCC via the MAPK signaling pathway and provide new mechanistic insights into the nonimmunological role of CD73 in HNSCC.

Combine contrast-enhanced 3D T2-weighted short inversion time inversion recovery MR neurography with MR angiography at 1.5 T in the assessment of brachial plexopathy.

PURPOSE: To explore the benefits of using a single injection of contrast agent at a 1.5 T system to perform both contrast-enhanced MR angiography (MRA) and 3D-T2-STIR MR neurography (MRN) to assess of brachial plexopathy. METHODS: In this prospective study, 27 patients with suspected brachial plexopathy, received an imaging procedure composed sequentially of non-enhanced 3D-T2-STIR, CE-MRA, and contrast-enhanced 3D-T2-STIR, using a 1.5 T MR scanner. Signal intensities and contrast ratios were compared with and without contrast agent. The non-enhanced and contrast-enhanced 3D-T2-STIR images were mixed for two experienced radiologists to rate image diagnostic quality in a blind manner. 3D images of MRN and MRA were merged to reveal the spatial relation between brachial plexopathy and concomitant vascular disorders. RESULTS: By comparing the non-enhanced with contrast-enhanced 3D-T2-STIR images, it revealed that the use of the contrast agent in 3D-T2-STIR MRN could significantly suppress the background signals contributed by small vein (P < 0.001), lymph node (P < 0.001), muscle (P < 0.001) and bone (P < 0.001). This improved the contrast ratios between the brachial plexus and its surrounding tissues (P < 0.001) and boosted the image's quality score (P < 0.01). Examining both CE-MRA and 3D-T2-STIR images revealed a relatively high incidence of concurrent vascular dysfunction in brachial plexopathy, with 39% of confirmed cases accompanied with subclavian and axillary vessel abnormalities. CONCLUSION: Combining contrast-enhanced 3D-T2-STIR MRN with MRA at a 1.5 T system significantly suppresses background signals, improves brachial-plexus display, and provides a direct assessment for both brachial plexus lesion and surrounding vascular injury.

A Novel Approach for Imaging of Thoracic Outlet Syndrome Using Contrast-Enhanced Magnetic Resonance Angiography (CE-MRA), Short Inversion Time Inversion Recovery Sampling Perfection with Application-Optimized Contrasts Using Different Flip Angle Evolutions (T2-STIR-SPACE), and Volumetric Interpolated Breath-Hold Examination (VIBE).

BACKGROUND The aim of this study was to introduce a novel method combining contrast-enhanced magnetic resonance angiography (CE-MRA), short inversion time inversion recovery sampling perfection with application-optimized contrasts using different flip angle evolutions (T2-STIR-SPACE) and volumetric interpolated breath-hold examination (VIBE) sequences in the assessment of thoracic outlet syndrome (TOS). MATERIAL AND METHODS CE-MRA, T2-STIR-SPACE, and VIBE techniques were employed to evaluate neurovascular bundles in 27 patients clinically suspected of TOS. Images were evaluated to determine the cause of neurovascular bundle compression. Surgical exploration was performed in patients with abnormal magnetic resonance imaging (MRI) results. RESULTS Twenty patients were found to be abnormal: 6 cases showed only neurogenic TOS and the correlates included infraclavicular hemangiomas (n=1) and transverse cervical artery (n=5). Arterial-neurogenic TOS was found in 4 cases, including subclavian lymph node metastasis from breast cancer (n=3) and schwannoma (n=1). Arterial-venous-neurogenic TOS was found in 1 subject, and the correlates included a fibrous band from the cervical rib and elongated C7 transverse process. In this case, the subclavian artery/vein was compressed dynamically. Venous-neurogenic TOS was noted in one subject. Nine patients were considered as post-traumatic TOS, including brachial plexus edema (n=3), the brachial plexus rupture (n=2), peri-brachial plexus effusion (n=3), and stenosis of the SCA (n=1). In the remaining 7 patients, MRI did not detect abnormalities. CONCLUSIONS TOS can be evaluated by CE-MRA, T2-STIR-SPACE, and VIBE during a single examination, with a reduced contrast material dose. This imaging modality performs well in showing the anatomical structure of the neurovascular bundle and the cause of the compression.

Playing Music for Hospitalized Patients Enhances Mood and Reduces Perceptions of Pain.

OBJECTIVES: For most people, music serves as a calming influence or as a pleasurable stimulus that lifts their spirits. In an attempt to both distract and cheer up hospitalized patients, we designed a brief intervention that would bring music to their hospital rooms in attempt to enhance their mood and minimize their awareness of pain. METHODS: In this prospective study of adult patients on the general medicine ward at Johns Hopkins Hospital, we assessed the impact of self-selected music delivery on patients' mood and their perception of pain. Patients' mood and pain were assessed using the modified Hospital Anxiety and Depression Scale and the Verbal Numerical Rating Scale, a validated 10-point Likert pain scale. RESULTS: Of the 151 patients studied, their mean age was 57 years, 57% were women, and 65% were white. Ninety-seven percent of patients described listening to music regularly at home, but only 28% of patients reported that they had listened to any music since being in the hospital (P < 0.0001). The patients' modified Hospital Anxiety and Depression Scale score and pain score were decreased significantly (-4.99, standard error 0.45, P < 0.0001, and -0.72, standard error 1.51, P < 0.0001, respectively) after listening to a couple of their favorite songs. CONCLUSIONS: This study demonstrates that bringing music to hospitalized patients and encouraging them to listen to their favorite songs are genuinely appreciated. If this intervention can enhance moods and reduce pain for patients in the hospital, then directing resources to make it sustainable may be justified.

Monoamine oxidase B inhibits epithelial-mesenchymal transition and trigger apoptosis via targeting ERK1/2 signaling pathway in head and neck squamous cell carcinoma.

BACKGROUND: Monoamine oxidase B (MAOB), a flavin monoamine oxidase, regulates biogenic and xenobiotic amine oxidative deaminization. We demonstrate MAOB expression in head and neck epithelium and its biological importance in head and neck squamous cell carcinoma (HNSCC) development. METHODS: First, we found a possible MAOB downregulation in HNSCC using bioinformatic analysis. Second, we validated MAOB expression changes in vitro and assessed its tumorigenicity in HNSCC. Finally, preclinical xenograft models further confirmed our findings. RESULTS: Results proved that MAOB was significantly reduced in HNSCC tissues and cell lines. By comparing MAOB localization in patient specimens, we found that epithelial basal cells express MAOB and that it changes throughout HNSCC development. We observed that MAOB overexpression inhibited HNSCC cell malignancy via lentiviral transfection. We additionally discovered that selegiline partly counter-regulated MAOB overexpression-induced phenotypes in HNSCC cells. CONCLUSIONS: We found that MAOB is a potent biomarker and a unique and essential indication of HNSCC carcinogenesis.

Qi-Zhi-Wei-Tong granules alleviates chronic non-atrophic gastritis in mice by altering the gut microbiota and bile acid metabolism.

ETHNOPHARMACOLOGICAL RELEVANCE: In traditional Chinese medicine, Qi-zhi-wei-tong granule (QZWT) significantly reduced the major gastrointestinal and psychological symptoms of functional dyspepsia. AIM OF THE STUDY: We aimed to explore the therapeutic effect of QZWT treated chronic non-atrophic gastritis (CNAG) and to elucidate its potential mechanism. MATERIALS AND METHODS: The composition of QZWT was analysed by UPLC-Q/TOF-MS. The CNAG mice model was established by chronic restraint stress (CRS) in combination with iodoacetamide (IAA). Morphological staining was utilized to reveal the impact of QZWT on stomach and gut integrity. RT‒qPCR and ELISA were used to measure proinflammatory cytokines in the stomach, colon tissues and serum of CNAG mice. Next-generation sequencing of 16 S rDNA was applied to analyse the gut microbiota community of faecal samples. Finally, we investigated the faecal bile acid composition using GC‒MS. RESULTS: Twenty-one of the compounds from QZWT were successfully identified by UPLC-Q/TOF-MS analysis. QZWT enhanced gastric and intestinal integrity and suppressed inflammatory responses in CNAG mice. Moreover, QZWT treatment reshaped the gut microbiota structure by increasing the levels of the Akkermansia genus and decreasing the populations of the Desulfovibrio genus in CNAG mice. The alteration of gut microbiota was associated with gut bacteria BA metabolism. In addition, QZWT reduced BAs and especially decreased conjugated BAs in CNAG mice. Spearman's correlation analysis further confirmed the links between the changes in the gut microbiota and CNAG indices. CONCLUSIONS: QZWT can effectively inhibited gastrointestinal inflammatory responses of CNAG symptoms in mice; these effects may be closely related to restoring the balance of the gut microbiota and regulating BA metabolism to protect the gastric mucosa. This study provides a scientific reference for the pathogenesis of CNAG and the mechanism of QZWT treatment.

The bHLH-zip transcription factor SREBP regulates triterpenoid and lipid metabolisms in the medicinal fungus Ganoderma lingzhi.

Ganoderic acids (GAs) are well recognized as important pharmacological components of the medicinal species belonging to the basidiomycete genus Ganoderma. However, transcription factors directly regulating the expression of GA biosynthesis genes remain poorly understood. Here, the genome of Ganoderma lingzhi is de novo sequenced. Using DNA affinity purification sequencing, we identify putative targets of the transcription factor sterol regulatory element-binding protein (SREBP), including the genes of triterpenoid synthesis and lipid metabolism. Interactions between SREBP and the targets are verified by electrophoretic mobility gel shift assay. RNA-seq shows that SREBP targets, mevalonate kinase and 3-hydroxy-3-methylglutaryl coenzyme A synthetase in mevalonate pathway, sterol isomerase and lanosterol 14-demethylase in ergosterol biosynthesis, are significantly upregulated in the SREBP overexpression (OE::SREBP) strain. In addition, 3 targets involved in glycerophospholipid/glycerolipid metabolism are upregulated. Then, the contents of mevalonic acid, lanosterol, ergosterol and 13 different GAs as well as a variety of lipids are significantly increased in this strain. Furthermore, the effects of SREBP overexpression on triterpenoid and lipid metabolisms are recovered when OE::SREBP strain are treated with exogenous fatostatin, a specific inhibitor of SREBP. Taken together, our genome-wide study clarify the role of SREBP in triterpenoid and lipid metabolisms of G. lingzhi.

Characteristics of the Genome, Transcriptome and Ganoderic Acid of the Medicinal Fungus Ganoderma lingzhi.

Ganoderma (Ganodermaceae) is a genus of edible and medicinal mushrooms that create a diverse set of bioactive compounds. Ganoderma lingzhi has been famous in China for more than 2000 years for its medicinal properties. However, the genome information of G. lingzhi has not been characterized. Here, we characterized its 49.15-Mb genome, encoding 13,125 predicted genes which were sequenced by the Illumina and PacBio platform. A wide spectrum of carbohydrate-active enzymes, with a total number of 519 CAZymes were identified in G. lingzhi. Then, the genes involved in sexual recognition and ganoderic acid (GA, key bioactive metabolite) biosynthesis were characterized. In addition, we identified and deduced the possible structures of 20 main GA constituents by UPLC-ESI-MS/MS, including a new special ganochlearic acid A. Furthermore, 3996 novel transcripts were discovered, and 9276 genes were predicted to have the possibility of alternative splicing from RNA-Seq data. The alternative splicing genes were enriched for functional categories involved in protein processing, endocytosis, and metabolic activities by KEGG. These genomic, transcriptomic, and GA constituents' resources would enrich the toolbox for biological, genetic, and secondary metabolic pathways studies in G. lingzhi.

Dual antioxidant activity and the related mechanisms of a novel pentapeptide GLP4 from the fermented mycelia of Ganoderma lingzhi.

Oxidative stress causes chronic inflammation, and mediates various diseases. The discovery of antioxidants from natural sources is important to research. Here we identified a novel antioxidant peptide (GLP4) from Ganoderma lingzhi mycelium and investigated its antioxidant type and potential protective mechanisms. Through free radical scavenging assay, active site shielding validation, superoxide dismutase (SOD) activity assay, and lipid peroxidation assay, we demonstrated that GLP4 was a novel protective agent with both direct and indirect antioxidant activities. GLP4 could directly enter human umbilical vein endothelial cells (HUVECs) as an exogenous substance. Meanwhile, GLP4 promoted the nuclear translocation of nuclear factor erythroid-2-related factor 2 (Nrf2) and activated the Nrf2/antioxidant response element (ARE) signaling pathway, exhibiting antioxidant and anti-apoptotic cytoprotective effects on hydrogen peroxide (H2O2)-induced HUVECs. Pull-down experiments of GLP4 target proteins, bioinformatics analysis and molecular docking further revealed that GLP4 mediated Nrf2 activation through binding to phosphoglycerate mutase 5 (PGAM5). The results suggested that GLP4 is a novel peptide with dual antioxidant activity and has promising potential as a protective agent in preventing oxidative stress-related diseases.

The Identification of Stemness-Related Genes in the Risk of Head and Neck Squamous Cell Carcinoma.

OBJECTIVES: This study aimed to identify genes regulating cancer stemness of head and neck squamous cell carcinoma (HNSCC) and evaluate the ability of these genes to predict clinical outcomes. MATERIALS AND METHODS: The stemness index (mRNAsi) was obtained using a one-class logistic regression machine learning algorithm based on sequencing data of HNSCC patients. Stemness-related genes were identified by weighted gene co-expression network analysis and least absolute shrinkage and selection operator analysis (LASSO). The coefficient of LASSO was applied to construct a diagnostic risk score model. The Cancer Genome Atlas database, the Gene Expression Omnibus database, Oncomine database and the Human Protein Atlas database were used to validate the expression of key genes. Interaction network analysis was performed using String database and DisNor database. The Connectivity Map database was used to screen potential compounds. The expressions of stemness-related genes were validated using quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: TTK, KIF14, KIF18A and DLGAP5 were identified. Stemness-related genes were upregulated in HNSCC samples. The risk score model had a significant predictive ability. CDK inhibitor was the top hit of potential compounds. CONCLUSION: Stemness-related gene expression profiles may be a potential biomarker for HNSCC.

Identification of enhancer RNAs for the prognosis of head and neck squamous cell carcinoma.

BACKGROUND: Enhancer RNAs (eRNAs) play an important role in carcinogenesis. The landscape of eRNAs in head and neck squamous cell carcinoma (HNSCC) remains largely unknown. METHODS: The eRNA expression matrix was obtained from the enhancer RNA in the cancer database. Functional enrichment analyses were performed using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG). Prognostic eRNAs were identified using Cox regression analysis, and a prognostic prediction model was constructed based on coefficients. RESULTS: KEGG analysis showed that eRNA-related transcription factors were mainly enriched in herpes simplex virus 1 (HSV1) infection. The zinc finger (ZNF) family may play an essential role in HNSCC. ENSR00000188847, ENSR00000250663, ENSR00000313345, ENSR00000317887, and ENSR00000336429 were identified. The prediction model was robust. CONCLUSIONS: We constructed a robust 5-eRNA prognostic prediction model, and these eRNAs are potential biomarkers for HNSCC prognosis.

CLPTM1L Is a Novel Putative Oncogene Promoting Tumorigenesis in Oral Squamous Cell Carcinoma.

This study aimed to explore the function of CLPTM1L in oral squamous cell carcinoma and mechanism of tumorigenesis. The expression of CLPTM1L was detected by immunohistochemistry. The localization in cells was detected by immunofluorescence. Cell invasion, proliferation, and migration were detected by transwell, CCK-8 and scratch-wound test. The possible characteristics of CLPTM1L were analysed in TCGA, GO, KEGG and String databases. IHC revealed that the expression of CLPTM1L in 92 cases of OSCC tissues was significantly higher (P < 0.01) than 29 cases of normal oral epithelium tissues. The expression of CLPTM1L was significantly higher in oral squamous cell carcinoma in TCGA database. CLPTM1L expression was not significantly correlated with the patients' clinical parameters. High expression of CLPTM1L was associated with worse prognosis. Cox regression analysis demonstrated that the CLPTM1L expression was the significant risk factor. CLPTM1L was mainly localized in the perinuclear cytoplasm. The vitro studies revealed that the knockdown of CLPTM1L suppressed invasion, proliferation and migration. CLPTM1L related genes were enriched in protein processing in the endoplasmic reticulum, protein folding, endoplasmic reticulum formation, N-glycan biosynthesis, and protein hydroxylation. Highly expressed CLPTM1L may contribute to a poor prognosis and increase invasion, proliferation and migration of oral squamous cell carcinoma. CLPTM1L may play an important role in tumorgenesis and would be a valuable target gene for the treatment of oral squamous cell carcinoma.

Extracellular Matrix Characterization in Gastric Cancer Helps to Predict Prognosis and Chemotherapy Response.

The extracellular matrix (ECM) plays a central role in the formation of the tumor microenvironment. The deposition of the ECM is associated with poor prognosis in a variety of tumors. Aberrant ECM deposition could undermine the effect of chemotherapy and immunotherapy. However, there is no systematic analysis on the relationship between the ECM and prognosis or chemotherapy effect. In the present study, we applied the gene set variation analysis (GSVA) algorithm to score 2199 canonical pathways in 2125 cases of probe or sequencing data and identified the core matrisome as the driving factor in gastric cancer progression. We classified gastric cancer samples into three clusters according to the composition of the ECM and evaluated clinical and multi-omics characterization of ECM phenotypes. The ECM score was evaluated by GSVA score of core matrisome and a higher ECM score predicted poor prognosis of gastric cancer [Hazard Ratio (HR), 2.084; p-value < 2 × 10-16]. In The Cancer Genome Atlas (TCGA) cohort and KUGH, YUSH, and KUCM cohorts, we verified that patients with a low ECM score could benefit from chemotherapy. By contrast, patients with a high ECM score did not achieve satisfactory response from chemotherapy. Determining the characteristics of the ECM microenvironment might help to predict the prognosis and chemotherapy response of patients with gastric cancer, and help to resolve the enigma of chemoresistance acquisition, as well as providing inspiration to develop combination therapy.

Identification of candidate biomarkers in ovarian cancer serum by depletion of highly abundant proteins and differential in-gel electrophoresis.

Ovarian cancer is the fifth leading cause of cancer death for women in the US, yet survival rates are over 90% when it is diagnosed at an early stage, highlighting the need for biomarkers for early detection. To enhance the discovery of tumor-specific proteins that could represent novel serum biomarkers for ovarian cancer, we depleted serum of highly abundant proteins which can mask the detection of proteins present in serum at low concentrations. Three commercial immunoaffinity columns were used in parallel to deplete the highly abundant proteins in serum from 60 patients with serous ovarian carcinoma and 60 non-cancer controls. Medium and low abundance serum proteins from each serum pool were then evaluated by the quantitative proteomic technique of differential in-gel electrophoresis. The number of protein spots that were elevated in ovarian cancer sera by at least twofold ranged from 36 to 248, depending upon the depletion and separation methods. From the 33 spots picked for MS analysis, nine different proteins were identified, including the novel candidate ovarian cancer biomarkers leucine-rich alpha2 glycoprotein-1 and ficolin 3. Western blotting validated the relative increases in serum protein levels for three of the proteins identified, demonstrating the utility of this approach for the identification of novel serum biomarkers for ovarian cancer.

Synergistic Adsorption for Parabens by an Amphiphilic Functionalized Polypropylene Fiber with Tunable Surface Microenvironment.

A series of novel amphiphilic functionalized fibers with polarity tunable surface microenvironment were constructed by introducing hydrophilic polyamines and hydrophobic linear alkyl chain groups, aiming to selectively remove parabens from water. In addition, Fourier-transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy, etc. were employed to determine the successful preparation of amphiphilic functionalized fibers. The adsorption experimental data indicated that the amphiphilic fibers showed excellent selectivity for parabens. In the amphiphilic fibers, hydrogen bonding and hydrophobic interaction existing in one molecular unit can effectively act together to enhance the interaction between substrate and fibers. Kinetic studies illustrated that the adsorption process was a physical adsorption with chemical characteristics. The overall initial adsorption rate together with the stepwise adsorption rate was quantified, and it is inferred that the hydrophobic interaction plays a leading role in the first step of the adsorption process. Moreover, the Freundlich model well described the sorption process with a maximum adsorption of 138.4 mg/g. What's more, the fiber still keeps excellent adsorption capacity (>90%) even after 10 adsorption/desorption cycles, which certifies it is an excellent adsorbent and can be utilized to remove paraben in practice.

Prevalence and characterisation of diagnostic error among 7-day all-cause hospital medicine readmissions: a retrospective cohort study.

BACKGROUND: The prevalence and aetiology of diagnostic error among hospitalised adults is unknown, though likely contributes to patient morbidity and mortality. We aim to identify and characterise the prevalence and types of diagnostic error among patients readmitted within 7 days of hospital discharge. METHODS: Retrospective cohort study at a single urban academic hospital examining adult patients discharged from the medical service and readmitted to the same hospital within 7 days between January and December 2018. The primary outcome was diagnostic error presence, identified through two-physician adjudication using validated tools. Secondary outcomes included severity of error impact and characterisation of diagnostic process failures contributing to error. RESULTS: There were 391 cases of unplanned 7-day readmission (5.2% of 7507 discharges), of which 376 (96.2%) were reviewed. Twenty-one (5.6%) admissions were found to contain at least one diagnostic error during the index admission. The most common problem areas in the diagnostic process included failure to order needed test(s) (n=11, 52.4%), erroneous clinician interpretation of test(s) (n=10, 47.6%) and failure to consider the correct diagnosis (n=8, 38.1%). Nineteen (90.5%) of the diagnostic errors resulted in moderate clinical impact, primarily due to short-term morbidity or contribution to the readmission. CONCLUSION: The prevalence of diagnostic error among 7-day medical readmissions was 5.6%. The most common drivers of diagnostic error were related to clinician diagnostic reasoning. Efforts to reduce diagnostic error should include strategies to augment diagnostic reasoning and improve clinician decision-making around diagnostic studies.

Digitoxin inhibits proliferation of multidrug-resistant HepG2 cells through G2/M cell cycle arrest and apoptosis.

Hepatocellular carcinoma (HCC) remains a challenge in the medical field due to its high malignancy and mortality rates particularly for HCC, which has developed multidrug resistance. Therefore, the identification of efficient chemotherapeutic drugs for multidrug resistant HCC has become an urgent issue. Natural products have always been of significance in drug discovery. In the present study, a cell-based method was used to screen a natural compound library, which consisted of 78 compounds, and the doxorubicin-resistant cancer cell line, HepG2/ADM, as screening tools. The findings of the present study led to the shortlisting of one of the compounds, digitoxin, which displayed an inhibitory effect on HepG2/ADM cells, with 50% inhibitory concentration values of 132.65±3.83, 52.29±6.26, and 9.13±3.67 nM for 24, 48, and 72 h, respectively. Immunofluorescence, western blotting and cell cycle analyses revealed that digitoxin induced G2/M cell cycle arrest via the serine/threonine-protein kinase ATR (ATR)-serine/threonine-protein kinase Chk2 (CHK2)-M-phase inducer phosphatase 3 (CDC25C) signaling pathway in HepG2/ADM cells, which may have resulted from a DNA double-stranded break. Digitoxin also induced mitochondrial apoptosis, which was characterized by changes in the interaction between Bcl-2 and Bax, the release of cytochrome c, as well as the activation of the caspase-3 and -9. To the best of our knowledge, the present study is the first report that digitoxin displays an anti-HCC effect on HepG2/ADM cells through G2/M cell cycle arrest, which was mediated by the ATR-CHK2-CDC25C signaling pathway and mitochondrial apoptosis. Therefore, digitoxin could be a promising chemotherapeutic agent for the treatment of patients with HCC.

Digitoxin inhibits HeLa cell growth through the induction of G2/M cell cycle arrest and apoptosis in vitro and in vivo.

Cervical cancer is the fourth most common gynecological malignancy affecting the health of women worldwide and the second most common cause of cancer­related mortality among women in developing regions. Thus, the development of effective chemotherapeutic drugs for the treatment of cervical cancer has become an important issue in the medical field. The application of natural products for the prevention and treatment of various diseases, particularly cancer, has always attracted widespread attention. In the present study, a library of natural products composed of 78 single compounds was screened and it was found that digitoxin exhibited the highest cytotoxicity against HeLa cervical cancer cells with an IC50 value of 28 nM at 48 h. Furthermore, digitoxin exhibited extensive antitumor activities in a variety of malignant cell lines, including the lung cancer cell line, A549, the hepatoma cell line, MHCC97H, and the colon cancer cell line, HCT116. Mechanistically, digitoxin caused DNA double­stranded breaks (DSBs), inhibited the cell cycle at the G2/M phase via the ataxia telangiectasia mutated serine/threonine kinase (ATM)/ATM and Rad3­related serine/threonine kinase (ATR)­checkpoint kinase (CHK1)/checkpoint kinase 2 (CHK2)­Cdc25C pathway and ultimately triggered mitochondrial apoptosis, which was characterized by the disruption of Bax/Bcl­2, the release of cytochrome c and the sequential activation of caspases and poly(ADP­ribose) polymerase (PARP). In addition, the in vivo anticancer effect of digitoxin was confirmed in HeLa cell xenotransplantation models. On the whole, the findings of the present study demonstrate the efficacy of digitoxin against cervical cancer in vivo and elucidate its molecular mechanisms, including DSBs, cell cycle arrest and mitochondrial apoptosis. These results will contribute to the development of digitoxin as a chemotherapeutic agent in the treatment of cervical cancer.

Residual micro organic pollutants and their biotoxicity of the effluent from the typical textile wastewater treatment plants at Pearl River Delta.

This work investigated the biotoxicity and the residual dissolved organic matter (DOM) of the effluents from nine typical full-scale textile plants located at Pearl River Delta (PRD) in Guangdong province, China. The fluorescence regional integration (FRI) analysis showed that the tryptophan-like (II), soluble microbial product-like (IV) and fulvic acid-like substances (III) were the dominant compounds in the DOM. The acute toxicity test showed toxic effects still remained in most textile effluents, which might attribute to the undegraded dyes or aromatic compounds. Combining with the results from multiple methods, it indicated that the selected nine textile wastewater treatment plants (tWWTPs) all contained some residual micro organic pollutants in their effluents, and the residual benzene-derived products or aromatic amines were probably the toxicity-causing substances. Both ozonization and membrane filtration were capable of further decreasing the content of residual DOM, but by comprehensively considering the effects of removing DOM and biotoxicity, membrane filtration was better than ozonization.