FAM64A aggravates proliferation, invasion, lipid droplet formation, and chemoresistance in gastric cancer: A biomarker for aggressiveness and a gene therapy target.

FAM64A is a mitogen-induced regulator of the metaphase and anaphase transition. Here, we found that FAM64A messenger RNA (mRNA) and protein expression levels were higher in gastric cancer tissue than in normal mucosa (p < .05). FAM64A methylation was negatively correlated with FAM64A mRNA expression (p < .05). The differentially expressed genes of FAM64A were mainly involved in digestion, potassium transporting or exchanging ATPase, contractile fibers, endopeptidase, and pancreatic secretion (p < .05). The FAM64A-related genes were principally categorized into ubiquitin-mediated proteolysis, cell cycle, chromosome segregation and mitosis, microtubule binding and organization, metabolism of amino acids, cytokine receptors, lipid droplet, central nervous system, and collagen trimer (p < .05). FAM64A protein expression was lower in normal gastric mucosa than intestinal metaplasia, adenoma, and primary cancer (p < .05), negatively correlated with older age, T stage, lymphatic and venous invasion, tumor, node, metastasis stage, and dedifferentiation (p < .05), and associated with a favorable overall survival of gastric cancer patients. FAM64A overexpression promoted proliferation, antiapoptosis, migration, invasion, and epithelial-mesenchymal transition via the EGFR/Akt/mTOR/NF-κB, while the opposite effect was observed for FAM64A knockdown. FAM64A also induced chemoresistance directly or indirectly through lipid droplet formation via ING5. These results suggested that upregulation of FAM64A expression might induce aggressive phenotypes, leading to gastric carcinogenesis and its subsequent progression. Thus, FAM64A could be regarded as a prognosis biomarker and a target for gene therapy.

Cordycepin enhances hyperthermia-induced apoptosis and cell cycle arrest by modulating the MAPK pathway in human lymphoma U937 cells.

BACKGROUND: Hyperthermia induces cancer cell death. However, the cytotoxic effect of hyperthermia is not sufficient. Cordycepin can also induce apoptosis in cancer cells and enhance the antitumoral activity of irradiation. To examine cordycepin-mediated enhancement of hyperthermia-induced apoptosis, this study investigated the combined effects and apoptotic mechanisms of hyperthermia and cordycepin on human leukemia U937 cells. METHODS: Cell viability and apoptosis were measured using MTT assays, Hoechst 33342 staining and Annexin V/PI double staining. The distribution of the cell cycle and sub-G1 phase, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were examined by flow cytometry. The expression of related proteins was analyzed by western blotting. RESULTS: Combined treatment with hyperthermia and cordycepin markedly augmented apoptosis by upregulating Bax and suppressing Bcl-2, Bid and activated caspase 3 and 8 expression, and apoptosis was decreased by Z-VAD-fmk (a pan caspase inhibitor). We also found that the MMP was significantly decreased and excessive ROS generation occurred. The combination treatment also induced arrest in the G2/M phase by downregulating cyclin dependent kinase 1 (CDK1) and cyclin B1 protein expression. Furthermore, it was observed that mitogen-activated protein kinase (MAPK) pathway including ERK, JNK and p38 signals was involved in the induction of apoptosis. The phosphorylated p38 and JNK were increased and ERK phosphorylation was decreased by the combined treatment. In addition, N-acetyl-L-cysteine (NAC) significantly protected the cells by restoring ROS levels and the activity of caspase-3, inactivating the MAPK pathway. CONCLUSION: Cordycepin significantly enhanced hyperthermia-induced apoptosis and G2/M phase arrest in U937 cells. The combined treatment enhanced apoptosis through the MAPK pathway and mitochondrial dysfunction, and these effects could be rescued by NAC. We report for the first time that cordycepin can be used as a hyperthermia sensitizer to treat leukemia.

The effects of REG4 expression on chemoresistance of ovarian cancer.

Although ovarian cancer usually responds well to platinum- and taxane-based first-line chemotherapy, most patients develop recurrence and chemoresistance. Regenerating gene 4 (REG4) is a secretory protein involved in cell differentiation and proliferation. We found higher REG4 expression in ovarian cancer than in normal tissues (p < .05). Regenerating gene 4 expression was negatively associated with overall, progression-free or post-progression survival rates of patients with ovarian cancer receiving platinum or paclitaxel treatment (p < .05) according to a Kaplan-Meier plotter. Regenerating gene 4 overexpression resulted in either cisplatin or paclitaxel resistance, and apoptosis resistance in CAOV3 ovarian cancer cells (p < .05). REG4-transfected ovarian cancer cells showed stronger migration and invasion treated with cisplatin or paclitaxel (p < .05). Additionally, cisplatin or paclitaxel exposure led to the overexpression of phosphorylated phosphoinositide 3-kinase (p-PI3K), p-Akt, phosphorylated mammalian target of rapamycin (p-mTOR), glutathione S-transferase-π, survivin, and B-cell lymphoma 2 in REG4 transfectants compared with control cells (p < .05). These findings suggested that REG4 expression was up-regulated in ovarian cancer, and associated with poor survival and chemotherapy resistance. REG4 promoted the occurrence, development, and chemotherapy resistance of ovarian cancer by regulating cell proliferation, apoptosis, migration, and invasion, and PI3K/Akt/m-TOR signalling pathways. IMPACT STATEMENTWhat is already known on this subject? REG4 mRNA expression is up-regulated in many digestive cancers. High REG4 expression was associated with an adverse prognosis, high tumour and nodal stages, poor differentiation, and hepatic and peritoneal metastases of digestive cancers. REG4 expression conferred cancer cells with increased resistance to chemoradiotherapy, especially 5-FU-based treatment, by activating the MAPK/Erk/Bim signalling pathway.What do the results of this study add? REG4 was highly expressed in ovarian cancer. The expression of p-PI3K, p-AKT, p-mTOR, GST-π, survivin, and Bcl-2 was increased in REG4-overexpressing cells. High REG4 expression was significantly associated with inferior OS, PFS, and PPS rates in patients with ovarian cancer receiving platinum chemotherapy. REG4 mediated cisplatin and paclitaxel resistance in CAOV3 ovarian cancer cells. The percentage of apoptotic cells was markedly lower in REG4-transfected compared to mock-transfected cells after cisplatin or paclitaxel treatment.What are the implications of these findings for clinical practice and/or further research? This study aimed to evaluate the prognostic significance of REG4 expression in ovarian cancer treated with platinum and paclitaxel, to explore REG4 chemoresistance mechanisms to platinum and paclitaxel, and to provide a scientific experimental basis for the clinical treatment and outcome evaluation of ovarian cancer. In order to provide comprehensive clinical treatment of ovarian cancer, it is helpful to improve our understanding of multi-drug resistance and identify new cancer diagnostic biomarkers.

Two isopentenyl resorcinols from Peperomia tetraphylla.

Two isopentenyl resorcinols, peperobtusin B and peperobtusin C, have been isolated from Peperomia tetraphylla. Their structures were determined on the basis of spectroscopic methods, especially 1H NMR, 13C NMR, 2D NMR, and HR-TOF-MS. Two compounds were evaluated for cytostatic activity against G2, A 549, Hela and HCT 116 cells, but cytostatic activity of both compounds is weak.

Two new secolignans from the roots of Urtica fissa.

Two new secolignans, 3,4-trans-3-hydroxymethyl-4-[bis(4-hydroxy-3- methoxyphenyl)methyl]butyrolactone (1) and 3,4-trans-3-hydroxymethyl-4- [bis(3,4-dimethoxyphenyl)methyl]butyrolactone (2) have been isolated from the roots of Urtica fissa E.Pritz. Their structures were determined on the basis of spectroscopic methods, especially 1H NMR, 13C NMR, 2D NMR, and HR-ESI-MS. The inhibitory effects on N1 and N2, two subtypes of neuraminidases (NAs), of these two compounds were assayed.

The promoting effects of Grin2d expression in tumorigenesis and the aggressiveness of esophageal cancer.

Grin2d is an ionotropic NMDA receptor, a subunit of glutamate-dependent, and a facilitator of cellular calcium influx in neuronal tissue. In this study, we found that Grin2d expression was higher in esophageal cancer than in normal mucosa at both the mRNA and protein level using RT-PCR, bioinformatics analysis, and western blotting (p<0.05). Grin2d mRNA expression was positively correlated with old age, white race, heavy weight, distal location, adenocarcinoma, cancer with Barrett's lesion, or high-grade columnar dysplasia (p<0.05). The differential genes associated with Grin2d mRNA were involved in fat digestion and absorption, cholesterol metabolism, lipid transfer, lipoproteins, synaptic membranes, and ABC transporters (p<0.05). The Grin2d-related genes were classified into the following categories: metabolism of glycerolipids, galactose, and O-glycan, cell adhesion binding, actin binding, cadherin binding, the Hippo signaling pathway, cell-cell junctions, desmosomes, DNA-transcription activator binding, and skin development and differentiation (p<0.05). Grin2d immunoreactivity was positively correlated with distal metastasis and unfavorable overall survival in esophageal cancer (p<0.05). Grin2d overexpression promoted proliferation, migration, and invasion in esophageal cancer cells but blocked apoptosis (p<0.05) and increased the expression of PI3K, Akt and p-mTOR. Grin2d knockout caused the opposite effects. These findings indicated that upregulated Grin2d expression played an important role in esophageal carcinogenesis via the PI3K/Akt/mTOR pathway and might be a biological marker for aggressive tumor behavior and poor prognosis. Its silencing might represent a targeted therapy approach against esophageal cancer.

Molecular mechanisms of apoptosis induction by 2-dodecylcyclobutanone, a radiolytic product of palmitic acid, in human lymphoma U937 cells.

The irradiation of fat-containing food forms 2-dodecylcyclobutanone (2-DCB) from palmitic acid (PA). In this study, we investigated whether 2-DCB and PA induce apoptosis in human lymphoma U937 cells. We found that cell viability decreased by 2-DCB and apoptosis was induced by 2-DCB and PA. 2-DCB and PA significantly enhanced the formation of intracellular reactive oxygen species (ROS). Apoptosis induced by 2-DCB and PA was strongly prevented by an antioxidant, N-acetyl-L: -cysteine. The treatment with 2-DCB and PA resulted in the loss of mitochondrial membrane potential, and Fas, caspase-8 and caspase-3 activation. Pretreatment with a pan-caspase inhibitor (z-VAD) significantly inhibited apoptosis induced by 2-DCB and PA. Moreover, 2-DCB and PA also induced Bax up-regulation, the reduction in Bcl-2 expression level, Bid cleavage and the release of cytochrome c from the mitochondria to the cytosol. In addition, an increase in intracellular Ca(2+) concentration ([Ca(2+)](i)) was observed after the treatment with 2-DCB and PA. Our results indicated that intracellular ROS generation, the modulation of the Fas-mitochondrion-caspase-dependent pathway and the increase in [Ca(2+)](i) involved in apoptosis are induced by 2-DCB and PA in U937 cells.

A new acylated flavonoid glycoside from the flowers of Camellia nitidissima and its effect on the induction of apoptosis in human lymphoma U937 cells.

From the EtOH extract of the flowers of Camellia nitidissima Chi, a new acylated flavonoid glycoside, quercetin 7-O-(6"-O-E-caffeoyl)-ß-D-glucopyranoside (1), has been isolated, together with three known flavonoids: quercetin (2), quercetin 3-O-ß-D-glucopyranoside (3), and quercetin 7-O-ß-D-glucopyranoside (4). Their structures were elucidated on the basis of spectroscopic analysis. Compound 1 was shown to inhibit proliferation and to induce apoptosis of human lymphoma U937 cells.

Green Solvents for Lipid Extraction From Microalgae to Produce Biodiesel.

Microalgae are considered as the third-generation feedstock for biodiesel production, and lipid extraction plays a significant role in efficient production of biofuels. Numerous technologies including chemical, mechanical, and biological have been achieved but high efficiency and potential application on an industrial scale are still needed. This review discusses the factors that influence biodiesel quality and the relative green and sustainable solvents for lipid extraction.

Efficient Reaction Systems for Lignocellulosic Biomass Conversion to Furan Derivatives: A Minireview.

Lignocellulosic biomass as abundant, renewable, and sustainable carbon feedstock is an alternative to relieve the dependence on fossil fuels and satisfy the demands of chemicals and materials. Conversions of lignocellulosic biomass to high-value-added chemicals have drawn much attention recently due to the high availability of sustainable ways. This minireview surveys the recent trends in lignocellulosic biomass conversion into furan derivatives based on the following systems: (1) ionic liquids, (2) deep eutectic solvents, and (3) biphasic systems. Moreover, the current challenges and future perspectives in the development of efficient routes for lignocellulosic biomass conversion are provided.

Computational investigation of potent inhibitors against SARS-CoV-2 2'-O-methyltransferase (nsp16): Structure-based pharmacophore modeling, molecular docking, molecular dynamics simulations and binding free energy calculations.

The Coronavirus Disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, has created unprecedented public health and economic crises around the world. SARS-CoV-2 2'-O-methyltransferase (nsp16) adds a "cap" to viral RNA to maintain the stability of viral RNA, and inhibition of nsp16 activity may reduce viral proliferation, making this protein an attractive drug target. Here, we report the identification of several small molecule inhibitors of nsp16 by virtual screening. First, the nsp16-sinefungin complex (PDB ID: 6WKQ) was selected from the protein data bank. Asp6912, Cys6913, Asp6897 and Asp6928 were determined to be the key amino acids for sinefungin binding in the crystal structure of nsp16-sinefungin complex by molecular dynamics simulation. The complex structures in the stable binding trajectory of nsp16-sinefungin were than clustered through molecular dynamics RMSD analysis. Six clusters were generated, and six representative structures were selected to construct the pharmacophore based on the structure. These six pharmacophores were superimposed on the binding pocket to simplify and pick the common characteristics. The compounds obtained by the pharmacophore screening from Bionet and Chembiv databases were docked into the nsp16 active pocket. The candidate compounds were selected according to the molecular docking score and then screened by MM/GBSA. Finally, four candidate compounds were obtained. Four sets of 150ns molecular dynamics simulations were performed to determine whether candidate compounds could maintain stable interactions with key amino acids. The results of MD and MM/PBSA energy decomposition indicated that C1 and C2 could form a stable complex system with nsp16, and could form strong hydrogen bonds and salt bridges with the key amino acid Asp6897 and Asp6928. This study thus identifies and attempts to validate for the first time the potential inhibitory activities of C1 and C2 against nsp16, allowing the development of potent anti-COVID-19 drugs and unique treatment strategies.

The development of novel ionic liquid-based solid catalysts and the conversion of 5-hydroxymethylfurfural from lignocellulosic biomass.

Ionic liquids have attracted attention due to their excellent properties and potential for use as co-solvents, solvents, co-catalysts, catalysts, and as other chemical reagents. This mini-review focuses on the properties and structures of ionic liquids, the pretreatment of lignocellulosic biomass, and the development of novel ionic liquid-based solid catalysts for cellulose and hemicellulose derived HMF production.

Research Progress on Lignocellulosic Biomass Degradation Catalyzed by Enzymatic Nanomaterials.

Lignocellulose biomass (LCB) has extensive applications in many fields such as bioenergy, food, medicines, and raw materials for producing value-added products. One of the keys to efficient utilization of LCB is to obtain directly available oligo- and monomers (e. g., glucose). With the characteristics of easy recovery and separation, high efficiency, economy, and environmental protection, immobilized enzymes have been developed as heterogeneous catalysts to degrade LCB effectively. In this review, applications and mechanisms of LCB-degrading enzymes are discussed, and the nanomaterials and methods used to immobilize enzymes are also discussed. Finally, the research progress of lignocellulose biodegradation catalyzed by nano-enzymes was discussed.

Synthetic biology promotes the capture of CO2 to produce fatty acid derivatives in microbial cell factories.

Environmental problems such as greenhouse effect, the consumption of fossil energy, and the increase of human demand for energy are becoming more and more serious, which force researcher to turn their attention to the reduction of CO2 and the development of renewable energy. Unsafety, easy to lead to secondary environmental pollution, cost inefficiency, and other problems limit the development of conventional CO2 capture technology. In recent years, many microorganisms have attracted much attention to capture CO2 and synthesize valuable products directly. Fatty acid derivatives (e.g., fatty acid esters, fatty alcohols, and aliphatic hydrocarbons), which can be used as a kind of environmentally friendly and renewable biofuels, are sustainable substitutes for fossil energy. In this review, conventional CO2 capture techniques pathways, microbial CO2 concentration mechanisms and fixation pathways were introduced. Then, the metabolic pathway and progress of direct production of fatty acid derivatives from CO2 in microbial cell factories were discussed. The synthetic biology means used to design engineering microorganisms and optimize their metabolic pathways were depicted, with final discussion on the potential of optoelectronic-microbial integrated capture and production systems.

Catalytic Upgrading of Lignocellulosic Biomass Sugars Toward Biofuel 5-Ethoxymethylfurfural.

The conversion of biomass into high-value chemicals through biorefineries is a requirement for sustainable development. Lignocellulosic biomass (LCB) contains polysaccharides and aromatic polymers and is one of the important raw materials for biorefineries. Hexose and pentose sugars can be obtained from LCB by effective pretreatment methods, and further converted into high-value chemicals and biofuels, such as 5-hydroxymethylfurfural (HMF), levulinic acid (LA), γ-valerolactone (GVL), ethyl levulinate (EL), and 5-ethoxymethylfurfural (EMF). Among these biofuels, EMF has a high cetane number and superior oxidation stability. This mini-review summarizes the mechanism of several important processes of EMF production from LCB-derived sugars and the research progress of acid catalysts used in this reaction in recent years. The influence of the properties and structures of mono- and bi-functional acid catalysts on the selectivity of EMF from glucose were discussed, and the effect of reaction conditions on the yield of EMF was also introduced.

The complete chloroplast genome sequence of Phalaenopsis wilsonii Rolfe, a vulnerable wild moth orchid species (Orchidaceae).

Phalaenopsis wilsonii Rolfe is a vulnerable wild moth orchid species with important horticultural value. The complete chloroplast genome sequence of P. wilsonii was generated by de novo assembly using whole genome next-generation sequencing to provide genomic data for further conservation genetics, phylogeny and molecular breeding in Phalaenopsis. The complete plastome of P. wilsonii is 145,096 bp in length, containing two inverted repeats (IR) regions (24,787 bp), a large single-copy (LSC) region (84,688 bp), and a small single-copy (SSC) region (10,834 bp). The chloroplast genome encoded 119 unique genes, including 73 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. The overall GC content of the whole genome is 36.9%. Phylogenetic analysis indicated P. wilsonii was closely related to P. lowii.

Development of Sustainable Catalytic Pathways for Furan Derivatives.

Biomass, the only globally available, renewable feedstock of organic carbon, is considered a viable alternative to fossil fuels. It can be efficiently utilized to produce various building blocks in accordance with green and sustainable chemistry principles. In this review, recent progress, such as the transformation of carbohydrates (C5 or C6 sugar, inulin, and cellulose) and their derivatives (furfural, hydroxymethylfurfural) into significant platform chemicals over polyoxometalates, zeolites, non-noble metals, and ionic liquids in single or multiphase, is evaluated.

Enhancement of radiation-induced apoptosis of human lymphoma U937 cells by sanazole.

Sanazole has been tested clinically as a hypoxic cell radiosensitizer. In this study, we determined whether sanazole enhances the radiation-induced apoptosis of human lymphoma U937 cells. Our results revealed that, compared with 10 mM sanazole or radiation alone, the combination of both resulted in a significant enhancement of apoptosis after 6 h, which was evaluated on the basis of DNA fragmentation, morphological changes, and phosphatidylserine externalization. Sanazole alone enhanced intracellular superoxide and hydrogen peroxide formation, which further increased when the cells were irradiated. Significant enhancement of Fas externalization, loss of mitochondrial membrane potential (MMP), and activation of caspase-3 and caspase-8 were observed after the combined treatment. Moreover, this combination could also enhance Bid activation, reduction of Hsp70 expression level and release of cytochrome c from the mitochondria to the cytosol. An immediate increase in the intracellular Ca(2+) concentration ([Ca(2+)](i)) was observed after the combined treatment. These results suggest that the intracellular superoxide and peroxide generated by sanazole might be involved in the enhancement of radiation-induced apoptosis, and that these effects are associated with modulation of the Fas-mitochondria-caspase-dependent pathway, an increase in [Ca(2+)](i), and a decrease in the Hsp70 expression levels.

Design, synthesis, and biological evaluation of artificial macrosphelides in the search for new apoptosis-inducing agents.

Various artificial macrosphelides were designed and synthesized, including ring-enlarged analogues and epothilone-hybrid compounds. Syntheses were accomplished in an efficient manner by using a ring-closing metathesis (RCM) strategy in a key macrocyclization step. Biological evaluation of these new macrosphelide-based derivatives revealed that several epothilone hybrids, in which a thiazole-containing side chain was incorporated, exhibited potent apoptosis-inducing activity toward human lymphoma cells. These activities were considerably enhanced relative to those of natural macrosphelide compounds. Structure-activity relationship studies revealed that the "ene-dicarbonyl" substructure is apparently essential for bioactivity.

Enhancement of hyperthermia-induced apoptosis by sanazole in human lymphoma U937 cells.

Sanazole has been tested clinically as a hypoxic cell radiosensitizer. The aim of the present study was to investigate whether sanazole enhances apoptosis induced by hyperthermia at 44 degrees C for 20 min in human lymphoma U937 cells. Sanazole alone induced continuous increase in the intracellular superoxide generation in a time-dependent manner and transient increase in the peroxide formation, which further were enhanced at 1 hour after HT treatment. Moreover, when the cells were treated first with 10 mM sanazole for 40 min, exposed to HT at 44 degrees C for 20 min and the cells were further treated with the drug at 37 degrees C for 6 h, a significant enhancement of HT-induced apoptosis was evidenced by DNA fragmentation, morphological changes and phosphatidylserine externalization. Studying the apoptotic pathways involved in this enhancement, we found that loss of the mitochondrial membrane potential, release of cytochrome c from mitochondria to cytosol, and activation of caspase-3 and caspase-8 was enhanced significantly in the U937 cells after the combined treatment. Moreover, this combination enhanced activation of Bid, and down regulation of Hsp70. In addition, an increase in the intracellular Ca(2+) concentration ([Ca(2+)](i)), and externalization of Fas were observed immediately after sanazole and HT treatment. Our data indicate that sanazole can enhance the hyperthermia induced-apoptosis through the Fas-caspase-8- and [Ca(2+)](i)-dependent apoptotic pathways. In addition, the down regulation of Hsp70 contributed to this enhancement.