Identification of necroptosis-related lncRNAs for prognosis prediction and screening of potential drugs in patients with colorectal cancer.

BACKGROUND: Tumor recurrence and metastasis lead to a poor prognosis in colorectal cancer (CRC). Necroptosis is closely related to the tumor microenvironment (TME) and affects tumor recurrence and metastasis. We aimed to stratify CRC patients according to necroptosis-related long noncoding RNAs (lncRNAs), which can be used to not only evaluate prognosis and improve precision medicine in clinical practice but also screen potential immunotherapy drugs. AIM: To stratify CRC patients according to necroptosis-related lncRNAs (NRLs), which can be used to not only evaluate prognosis and improve precision medicine in clinical practice but also screen potential immunotherapy drugs. METHODS: LncRNA expression profiles were collected from The Cancer Genome Atlas. NRLs were identified by coexpression analysis. Cox regression analysis identified a NRL signature. Then, the value of this signature was comprehensively and multidimensionally evaluated, and its reliability for CRC prognosis prediction was assessed with clinical CRC data and compared with that of six other lncRNA signatures. Gene set enrichment analysis, TME analysis and half-maximal inhibitory concentration (IC50) prediction were also performed according to the risk score (RS) of the signature. RESULTS: An 8-lncRNA signature significantly associated with overall survival (OS) was constructed, and its reliability was validated with clinical CRC data. Most of the areas under the receiver operating characteristic curves (AUCs) values for 1-, 3- and 5-year OS for this signature were higher than those for the other six lncRNA signatures. OS, disease-specific survival and the progression-free interval were all significantly poorer in the high-risk group. The RS of the signature showed good concordance with the predicted prognosis, with AUCs for 1-, 3- and 5-year OS of 0.79, 0.81 and 0.77, respectively. Additionally, the calibration plots for this signature combined with clinical factors showed that this combination could effectively improve the ability to predict OS. The RS was correlated with tumor stage, lymph node metastasis and distant metastasis. Most of the enriched Kyoto Encyclopedia of Genes and Genomes and Gene Ontology terms were tumor metastasis-related pathways in the high-risk group; these patients showed greater infiltration of immunosuppressive cells, such as cancer-associated fibroblasts, hematopoietic stem cells and M2 macrophages, but less infiltration of infiltrating antitumor effector immune cells, such as cluster of differentiation 8+ T cells and regulatory T cells (Tregs). We explored additional potential immune checkpoint genes and potential immunotherapeutic and chemotherapeutic drugs with relatively low IC50 values. CONCLUSION: We identified an NRL signature with strong fidelity that could stably predict prognosis and might be an indicator of the TME of CRC. Furthermore, additional potential immunotherapeutic and chemotherapeutic drugs were explored.

N6-methyladenosine Regulator-Mediated Immune Genes Identify Breast Cancer Immune Subtypes and Predict Immunotherapy Efficacy.

Breast cancer (BRCA) is a heterogeneous malignancy closely related to the tumor microenvironment (TME) cell infiltration. N6-methyladenosine (m6A) modification of mRNA plays a crucial regulator in regulating the immune microenvironment of BRCA. Immunotherapy represents a paradigm shift in BRCA treatment; however, lack of an appropriate approach for treatment evaluation is a significant issue in this field. In this study, we attempted to establish a prognostic signature of BRCA based on m6A-related immune genes and to investigate the potential association between prognosis and immunotherapy. We comprehensively evaluated the m6A modification patterns of BRCA tissues and non-tumor tissues from The Cancer Genome Atlas and the modification patterns with TME cell-infiltrating characteristics. Overall, 1,977 TME-related genes were identified in the literature. Based on LASSO and Cox regression analyses, the m6A-related immune score (m6A-IS) was established to characterize the TME of BRCA and predict prognosis and efficacy associated with immunotherapy. We developed an m6A-IS to effectively predict immune infiltration and the prognosis of patients with BRCA. The prognostic score model represented robust predictive performance in both the training and validation cohorts. The low-m6A-IS group was characterized by enhanced antigen presentation and improved immune checkpoint expression, further indicating sensitivity to immunotherapy. Compared with the patients in the high-score group, the overall survival rate after treatment in the low-score group was significantly higher in the testing and validation cohorts. We constructed an m6A-IS system to examine the ability of the m6A signature to predict the infiltration of immune cells of the TME in BRCA, and the m6A-IS system acted as an independent prognostic biomarker that predicts the response of patients with BRCA in immunotherapy.

Cellular apoptosis and cardiac dysfunction in STZ-induced diabetic rats attenuated by anthocyanins via activation of IGFI-R/PI3K/Akt survival signaling.

Anthocyanins are known cyto-protective agents against various stress conditions. In this study cardio-protective effect of anthocyanins from black rice against diabetic mellitus (DM) was evaluated using a streptozotocin (STZ)-induced DM rat model. Five-week-old male Wistar rats were administered with STZ (55 mg kg-1 , IP) to induce DM; rats in the treatment group received 250 mg oral anthocyanin/kg/day during the 4-week treatment period. DM and the control rats received normal saline through oral gavage. The results reveal that STZ-induced DM elevates myocardial apoptosis and associated proapoptotic proteins but down-regulates the proteins of IGF1R mediated survival signaling mechanism. Furthermore, the functional parameters such as the ejection-fraction and fraction-shortening in the DM rat hearts declined considerably. However, the rats treated with anthocyanins significantly reduced apoptosis and the associated proapoptotic proteins and further increased the survival signals to restore the cardiac functions in DM rats. Anthocyanin supplementation enhances cardiomyocyte survival and restores cardiac function.

[A project to reduce the incidence of facial pressure ulcers caused by prolonged surgery with prone positioning].

BACKGROUND & PROBLEMS: We observed in our institute a 13.6% incidence of prolonged surgery (>4 hours) induced facial pressure ulcers that required prone positioning. Causes identified included: (1) customized silicon face pillows used were not suited for every patient; (2) our institute lacked a standard operating procedure for prone positioning; (3) our institute lacked a postoperative evaluation and audit procedure for facial pressure ulcers. PURPOSE: We designed a strategy to reduce post-prolonged surgery facial pressure ulcer incidence requiring prone positioning by 50% (i.e., from 13.6% to 6.8%). RESOLUTIONS: We implemented the following: (1) Created a new water pillow to relieve facial pressure; (2) Implemented continuing education pressure ulcer prevention and evaluation; (3) Established protocols on standard care for prone-position patients and proper facial pressure ulcer identification; (4) Established a face pressure ulcers accident reporting mechanism; and (5) Established an audit mechanism facial pressure ulcer cases. RESULTS: After implementing the resolution measures, 116 patients underwent prolonged surgery in a prone position (mean operating time: 298 mins). None suffered from facial pressure ulcers. The measures effectively reduced the incidence of facial pressure ulcers from 13.6% to 0.0%. CONCLUSIONS: The project used a water pillow to relieve facial pressure and educated staff to recognize and evaluate pressure ulcers. These measures were demonstrated effective in reducing the incidence of facial pressure ulcers caused by prolonged prone positioning.

Interactions between octaarginine and U-937 human macrophages: global gene expression profiling, superoxide anion content, and cytokine production.

Cell penetrating peptides such as octaarginine (R8) have been widely used as intracellular delivery vectors to import biologically active membrane-impermeable molecules. However, before using these peptides clinically, human immune responses to them must be fully understood. Because macrophages are important for immune responses, we evaluated the interactions between R8 and a human U-937 cell line. Cytotoxicity, binding, internalization, genome-wide profiling of gene expression, intracellular superoxide anion content, and cytokine release were assessed after U-937 cells had been incubated with different amounts of R8. Cytotoxicity was limited for up to 40 microM of R8 and 24 h of incubation. Kinetic analysis of the binding and uptake of cells treated with fluorescein-5-isothiocynate-R8 showed time- and concentration-dependent increases. Microarray analysis identified 4386 genes time-dependently regulated when U-937 macrophages were exposed to 10 microM of R8 for 0.5 h and 4 h; the majority of these genes were upregulated for each time point. Thirty-five upregulated genes responded to the stimuli with immune functions, and, using real-time quantitative reverse transcriptase-polymerase chain reaction analysis, five genes - FOS, OSM, C1R, TNF, IL1R1 - were confirmed. R8 induced superoxide anion production after 0.5 h, but not after longer incubations. Incubating U-937 cells with R8 for up to 24 h did not release the proinflammatory cytokines TNF-alpha, IL-1beta, and IL-6. In summary, exposing U-937 macrophages to R8 did not induce proinflammatory cytokine release; however, it generated superoxide anion and affected gene expression.

Interactions between U-937 human macrophages and tyloxapol.

Tyloxapol is reported to prevent macrophages from reacting to endotoxin. However, the intracellular responses that tyloxapol induces in macrophages are still not fully explored. Hence, the objective of this study was to evaluate the intracellular events in macrophages treated with tyloxapol and assess the antioxidant properties of tyloxapol in endotoxin-activated macrophages. Using flow cytometry, we examined intracellular responses in macrophages: reactive oxygen species (ROS) content, mitochondria membrane potential, and cell cycle profiles. We also assessed the antioxidant properties of tyloxapol in endotoxin-activated macrophages. Kinetic hydrogen peroxide production tended to decline with increasing doses. Tyloxapol produced a progressive increase followed by a decline in superoxide anion production in macrophages with increasing doses. Tyloxapol also caused unstable fluctuations in mitochondrial membrane potential. Apoptosis had developed at higher doses after 4h of incubation time. After 2h of tyloxapol-pretreatment, tyloxapol acted as an antioxidant only at lower doses. Most tyloxapol-pretreated cells at lower doses fully recovered from the changes in superoxide anion and hydrogen peroxide production. Our findings contribute to a better understanding of the molecular action of tyloxapol in macrophages and how it protects macrophages against endotoxin.

Flow cytometric characterization of interactions between U-937 human macrophages and positively charged catanionic vesicles.

Catanionic vesicles are considered a potential alternative to liposomes for drug delivery systems because of their greater stability and lower cost. Before using catanionic vesicles in vivo, their interactions with macrophages must be fully understood because they are primarily removed from circulation by the macrophages of the mononuclear phagocyte system. Using flow cytometry, we examined the intracellular responses-reactive oxygen species (ROS) content, mitochondrial membrane potential, cell size and complexity, and cell cycle profiles-in U-937 human macrophages treated with positively charged catanionic vesicles. Kinetic hydrogen peroxide production initially increased at lower concentrations (4-10nM) but declined at higher concentrations (40 nM and 80 nM) over the entire incubation period. Superoxide content generation, however, increased over the entire concentration range and incubation period. Catanionic vesicles decreased mitochondrial membrane potential for every concentration after 4h of incubation but caused a significant fluctuation in mitochondrial membrane potential at 6h. After 6h of incubation, catanionic vesicles produced more changes in cell size and complexity than after 4h. The increase in the subG1 population of cells treated with catanionic vesicles at higher doses indicated that apoptosis progressed. Positively charged catanionic vesicles induced different activated patterns of ROS generation and changes in mitochondrial membrane potential than did cationic liposomes. The nature of the interactions between macrophages and catanionic vesicles is of great importance for the design of safer and more effective delivery systems for macrophages. Our findings contribute to a better understanding of the molecular action of catanionic vesicles in the cellular system.

Interactions between U-937 human macrophages and poly(propyleneimine) dendrimers.

Interest in using poly(propyleneimine) (PPI) dendrimers for biomedical applications is increasing. Before using PPI dendrimers in vivo, their interactions with macrophages must be fully understood because they are primarily removed from circulation by the macrophages of the mononuclear phagocyte system. However, few investigators have studied in detail the intracellular responses that cationic dendrimers induce in macrophages. Here we examined the intracellular responses-reactive oxygen species (ROS) content, mitochondria membrane potential, cell size and complexity, and cell cycle profiles-in U-937 human macrophages treated with poly(propyleneimine) dendrimers generation 2 (DAB 2.0) and 3 (DAB 3.0). Our study focused on the concentration ranges within which cell viability was greater than 90% after PPI dendrimers had been incubated for 16 h. For spontaneous ROS generation, DAB 2.0 did not consistently generate hydrogen peroxide production with increasing dosages over the entire culture period while it was capable of generating superoxide content except during the 12 h of incubation. In contrast, DAB 3.0 did not induce any hydrogen peroxide and superoxide production except for an abrupt increase of superoxide content at 60 microg/mL after 6 h of incubation. Our results showed that ROS responses in macrophages were strongly influenced by the nature of the dendrimer surface. Except at 3 h, DAB 2.0 increased mitochondrial membrane potential for every dose and culture period. In contrast, DAB 3.0 caused a significant fluctuation in mitochondrial membrane potential only at 6 h, compared with other incubation times. Exposing macrophages to PPI dendrimers caused dramatic and significant changes in macrophage cell size and complexity, and DAB 3.0 caused greater changes than DAB 2.0 did. For incubation times longer than 1 h, propidium iodide staining showed that cells treated with DAB 2.0 and 3.0 had a higher subG1 phase (indicative of apoptosis) than did untreated cells. PPI dendrimers induced different activated patterns in ROS generation and changes of mitochondrial membrane potential than did other carriers such as cationic liposomes and polyalkylcyanoacrylate. The nature of interactions between macrophages and PPI dendrimers is crucial for the design of safer and more effective delivery systems for macrophages. Our findings provide a novel insight into the cytotoxic effects at the molecular level that dendrimers cause in macrophages.

Remnant cationic dendrimers block RNA migration in electrophoresis after monophasic lysis.

Cationic dendrimers such as poly(amidoamine) (PAMAM) and poly(propyleneimine) (PPI) have attractive characteristics for the delivery of nucleic acid and various biomedical applications. Most studies have focused on cationic dendrimer-based intracellular delivery, and very few studies have focused on the non-specific interaction of remnant cationic dendrimers with total RNA after isolation directly from cells in vitro. We examined RNA isolation using the common method of monophasic lysis from human macrophage-like cells (U937) and mouse fibroblast cells (NIH/3T3) that had been exposed to dendrimers and DNA/dendrimer complexes using gel electrophoresis. We found that PAMAM and PPI dendrimers strongly altered the mobility of RNA in the gels. In addition, the extent of dendrimer-induced alteration in RNA mobility was directly dendrimer-generation-dependent: the alteration was greater with higher-generation dendrimers. We also found that DNA/dendrimer complexes at higher dendrimer to DNA ratios interacted with RNA after isolation while gene expression was maintained. The interactions between RNA and remnant dendrimers after isolation were caused by electrostatic bindings, and we recovered total RNA using high ionic strength solvents (2M NaCl solution) to disrupt the electrostatic forces binding dendrimers to RNA. Because RNA isolation is routinely used for biological applications, such dendrimer-induced alteration in RNA mobility should be accounted for in the further processing of RNA-related applications.