High-density lipoprotein reduces microglia activation and protects against experimental autoimmune encephalomyelitis in mice.

Studies have shown that high-density lipoprotein (HDL) is a powerful anti-atherosclerosis factor in vivo and in vitro, with anti-inflammatory effects, and it also plays an important role in the immune system and central nervous system (CNS). In this study, the BV2 microglia inflammation model and experimental autoimmune encephalomyelitis animal model were used to investigate the potential mechanism of HDL in multiple sclerosis. Our results show that HDL inhibits the activation of BV2 microglia in a model of BV2 microglia inflammation and were validated with primary microglia. HDL can down-regulate the expression of TNF-α, IL-6, iNOS and NO. Western blot results showed that HDL could reduce the expression levels of TLR4, CD14, MyD88 and NF-κB p65 LPS-induced microglia. In a mouse model of experimental autoimmune encephalomyelitis, hematoxylin-eosin (HE) staining showed decreased infiltration of inflammatory cells in brain and spinal cord tissues, and Luxol Fast Blue (LFB) staining showed significant improvement in spinal cord demyelination. We found that HDL reduced spinal cord and brain inflammation after EAE induction, inhibited the infiltration of CD68 and Iba-1 positive inflammatory cells, and reduced the production of multiple pro-inflammatory cytokines, including pro-inflammatory cytokines TNF-α, IL-6, and IL-1ß. Western blot showed that EAE mice HDL inhibited the activation of ERK1/2 and JNK in MAPK pathway and p-IκBα and P65 in NF-κB pathway. Taken together, our study suggests that HDL may influence microglia activation and inflammatory response in mice by regulating inflammatory signaling pathways, improving induction of experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis, and provides further insights into HDL therapy for multiple sclerosis.

Correlation of NUF2 Overexpression with Poorer Patient Survival in Multiple Cancers.

PURPOSE: NUF2 has been implicated in multiple cancers recently, suggesting NUF2 may play a role in the common tumorigenesis process. In this study, we aim to perform comprehensive meta-analysis of NUF2 expression in the cancer types included in the Cancer Genome Atlas (TCGA). MATERIALS AND METHODS: RNA-sequencing data in 31 cancer types in the TCGA data and 11 independent datasets were used to examine NUF2 expression. Silencing NUF2 using targeting shRNAs in hepatocellular carcinoma (HCC) cell lines was used to evaluate NUF2's role in HCC in vitro and in vivo. RESULTS: NUF2 up-regulation is significantly observed in 23 out of the 31 cancer types in the TCGA datasets and validated in 13 major cancer types using 11 independent datasets. NUF2 overexpression was clinically important as high NUF2 was significantly associated with tumor stages in eight different cancers. High NUF2 was also associated with significantly poorer patient overall survival and disease-free survival in eight and six cancers, respectively. We proceeded to validate NUF2 overexpression and its negative association with overall survival at the protein level in an independent cohort of 40 HCC patients. Compared to the non-targeting controls, NUF2 knockdown cells showed significantly reduced ability to grow, migrate into a scratch wound and invade the 8 µm porous membrane in vitro. Moreover, NUF2 knockdown cells also formed significantly smaller tumors than control cells in mouse xenograft assays in vivo. CONCLUSION: NUF2 up-regulation is a common feature of many cancers. The prognostic potential and functional impact of NUF2 up-regulation warrant further studies.

The emergence of the two cell fates and their associated switching for a negative auto-regulating gene.

BACKGROUND: Decisions in the cell that lead to its ultimate fate are important for fundamental cellular functions such as proliferation, growth, differentiation, development, and death. These cell fate decisions can be influenced by both the gene regulatory network and also environmental factors and can be modeled using simple gene feedback circuits. Negative auto-regulation is a common feedback motif in the gene circuits. It can act to reduce gene expression noise or induce oscillatory expression and is thought to lead to only one cell fate. Here, we present experimental and modeling data to suggest that a self-repressor circuit can lead to two cell fates under specific conditions. RESULTS: We show that the introduction of inducers capable of binding and unbinding to a self-repressing gene product (protein), thus regulating the associated gene, can lead to the emergence of two cell states. We suggest that the inducers can alter the effective regulatory binding and unbinding speed of the self-repressor regulatory protein to its destination DNA without changing the gene itself. The corresponding simulation results are consistent with the experimental findings. We propose physical and quantitative explanations for the origin of the two phenotypic cell fates. CONCLUSIONS: Our results suggest a mechanism for the emergence of multiple cell fates. This may explain the heterogeneity often observed among cell states, while illustrating that altering gene regulation strength can influence cell fates and their decision-making processes without genetic changes.

Function of different proportions of apolipoprotein A-I cysteine mutants and apolipoprotein A-V on recombinant high-density lipoproteins in vitro.

To explore the anti-atherosclerotic effects of recombinant high-density lipoproteins (rHDL) of apolipoprotein AI wild-type (apoA-Iwt), apolipoprotein AI Milano (apoA-IM), apolipoprotein AI (N74C) (apoA-I (N74C) )and apolipoprotein AV (apoA-V). We constructed rHDL liposomes (rHDLs), which included apoA-Iwt, apoA-IM, and apoA-I (N74C), followed by the synthesis of rHDLs, with the indicated ratios of apoA-Iwt, apoA-IM, apoA-I (N74C) and apoA-V. We investigated the anti-atherosclerotic effects by experiments including the DMPC clearance assay and experiments that assessed the in vitro antioxidation against low-density lipoprotein, the cellular uptake of oxidized low-density lipoprotein (oxLDL) and the in vitro intracellular lipid accumulation. Electron microscopy results revealed that as more apoA-V was present in rHDLs, the particle size of rHDLs was larger. The DMPC clearance assay subsequently showed that rHDL protein mixtures could promote DMPC turbidity clearance when more apoA-V was included in the reaction mixtures, with apoAV-rHDL showing the strongest turbidity clearance ability (P<0.05 vs AI-rHDL). In vitro antioxidation against low-density lipoprotein assays indicated that rHDLs containing apoA-V had increasing oxidation resistance against low-density lipoprotein (LDL) with higher apoA-V contents. Finally, cellular uptake of oxLDL and intracellular lipids suggested an apparent oxidation resistance to LDL oxidation in vitro and a reduced intracellular lipid accumulation in THP-1-derived macrophages, with AIM-rHDL demonstrating the greatest ability to decrease intracellular lipid accumulation. Different proportions of apolipoprotein A-I cysteine mutants and apolipoprotein A-V of rHDL changed the lipid binding capacity, particle size, and antioxidant capacity. These changes may show a beneficial effect of rHDL on atherosclerosis.

NUF2 is a valuable prognostic biomarker to predict early recurrence of hepatocellular carcinoma after surgical resection.

Early tumor recurrence after curative surgical resection poses a great challenge to the clinical management of hepatocellular carcinoma (HCC). We conducted whole genome expression microarrays on 64 primary HCC tumors with clinically defined recurrence status and cross-referenced with RNA-seq data from 18 HCC tumors in the Cancer Genome Atlas project. We identified a 77-gene signature, which is significantly associated with early recurrent (ER) HCC tumors. This ER-associated signature shows significant enrichment in genes involved in cell cycle pathway. We performed receiver operating characteristic (ROC) analysis to evaluate the prognostic biomarker potential of these 77 genes and Pearson correlation analysis to identify 11 close clusters. The one gene with the best area under the ROC curve in each of the 11 clusters was selected for validation using reverse-transcription quantitative PCR in an independent cohort of 24 HCC tumors. NUF2 was identified to be the minimal biomarker sufficient to discriminate ER tumors from LR tumors. NUF2 in combination with liver cirrhosis could significantly improve the detection of ER tumors with an AUROC of 0.82 and 0.85 in the test and validation cohort, respectively. In conclusion, NUF2 in combination with liver cirrhosis is a promising prognostic biomarker for early HCC recurrence.

Anti-Inflammatory Effects of HDL in Mice With Rheumatoid Arthritis Induced by Collagen.

Objective: To investigate the anti-inflammatory effects of high-density lipoprotein (HDL) in mice with rheumatoid arthritis (RA) induced by collagen. Methods: Male DBA/1 mice (8-week-old) were divided into three groups: control (treated with saline), collagen-induced arthritis (CIA), and CIA + HDL. CIA was induced with bovine type II collagen, and after the injection of bovine type II collagen, the CIA + HDL group received an injection of HDL on day 28 followed by HDL injections four times every 3 days. Mice were weighed, the paws were scored, and paw thickness was measured beginning on day 21. Additionally, the levels of tumor necrosis factor-alpha (TNF-α) and IL-6 were measured by ELISA kits, tissue sections of paws were stained with hematoxylin and eosin, and the inflammatory signaling pathway was analyzed by western blotting. Results: We found that the production of pro-inflammatory cytokines TNF-α and IL-6 in mice which received HDL decreased 45.14 and 35.02%, respectively. And we also found that HDL could significantly decrease the level of anti-type-II-collagen IgG2a and inhibit the neutrophil infiltration and cell proliferation and protect the ankle joint from type II collage-induced injury. Western blot analysis indicated that HDL could also inhibit the activation of the NF-κB, MAPK, and ERK signaling pathways in RA mice. Conclusion: HDL can inhibit the inflammation induced by bovine type II collagen and the development of RA.

Endoscopic surgery of a sinonasal inverted papilloma: Surgical strategy, follow-up, and recurrence rate.

BACKGROUND: Sinonasal inverted papilloma (SNIP) is noted for its high rate of recurrence and malignant transformation. Although many clinical studies have demonstrated the effectiveness of the endoscopic approach for SNIP, the surgical strategy has been the subject of much debate. OBJECTIVE: To evaluate the effectiveness of the endoscopic endonasal approach in SNIP. METHODS: A systematic review of patients with a diagnosis of SNIP and who had surgery at our institution from June 2005 to March 2013 was performed. All the patients who had postoperative follow-up for >2 years were enrolled. Each case was categorized into one of four stages as reported by Krouse. Demographic and tumor date, operative approach, complications, and recurrence rates were collected. RESULTS: A total of 125 patients were included in this study. There were 17 patients in stage 1, 40 in stage 2, 57 in stage 3, and 11 in stage 4. The overall recurrence rate was 8.0%. There was no significant difference in recurrence among the stages (all p > 0.05). Recurrence after endoscopic endonasal approach (8.4%) and a combined endoscopic and open exposure procedure (5.6%) were not significantly different (p > 0.05). The recurrence rate was significantly (p < 0.05) higher in patients with revision (15.6%) than in patients in the primary cases (3.8%). A common site of tumor origin was recorded to be from the maxillary sinus (40.2%). Twenty percent of recurrences were observed up to 5 years after surgery. CONCLUSION: Endoscopic surgery may be preferred for treating SNIP. The elevated recurrence rate after revision emphasized the significance of the first surgery. We encourage a follow-up period of at least 5 years.

Effect of lipid-bound apolipoprotein A-I cysteine mutant on ATF3 in RAW264.7 cells.

Activating transcription factor 3 (ATF3) is a TLR-induced repressor that plays an important role in the inhibition of specific inflammatory signals. We previously constructed recombinant high density lipoproteins (rHDL) (including rHDLWT, rHDLM, rHDL228 and rHDL74) and found that rHDL74 had a strong anti-inflammatory ability. In the present study, we investigate the roles of recombinant apolipoprotein A-I (ApoA-I) (rHDLWT) and its cysteine mutant HDLs (rHDLM, rHDL228 and rHDL74) on ATF3 function in RAW264.7 cells stimulated by lipopolysaccharide. Our results showed that compared with the LPS group, rHDL74 can decrease the level of TNF-α and IL-6, whereas rHDL228 increases their expression levels. RT-PCR and Western blotting results showed that compared with the LPS group, rHDL74, rHDLWT and rHDLM can markedly increase the expression level of ATF3, whereas the level of ATF3 decreases in the rHDL228 group. In summary, the different anti-inflammatory mechanisms of the ApoA-I cysteine mutants might be associated with the regulation of ATF3 level.

Special biochemical responses to nitrogen deprivation of filamentous oleaginous microalgae Tribonema sp.

Both filamentous microalgae Tribonema and unicellular microalgae Nanochloropsis are promising feedstock for biodiesel production. Nitrogen starvation increased lipid content in Nannochloropsis but decreased that in Tribonema. In this study, biochemical responses of Tribonema under different levels of nitrogen (0N, 0.05N, 0.1N and 1N-BG11) were investigated. 1N-BG11 was sufficient during 15-day-cultivation, while the other levels were nitrogen limited. Cell growth was interrupted with 0N-BG11, but no differences in biomass among 0.05N, 0.1N and 1N-BG11. Both protein and lipid contents (% of dry weight) declined gradually inversely to the increment in carbohydrate contents under the decreasement of nitrogen levels. Both assays and TEM results showed that the cytoplasm in Tribonema contained no starch. Compared to nitrogen-replete condition, the TAG content (% of dry weight) decreased obviously under nitrogen starvation. Different levels of nitrogen did not cause fundamental shifts in fatty acid profiles in Tribonema.

Co-expression of herpes simplex virus thymidine kinase and Escherichia coli nitroreductase by an hTERT-driven adenovirus vector in breast cancer cells results in additive anti-tumor effects.

Breast cancers especially in the late and metastatic stages remain refractory to treatment despite advances in surgical techniques and chemotherapy. Tumor-specific promoter-directed suicide gene therapy and adenoviral technology can be promising strategies for such advanced disease. Previous studies suggested that combining herpes simplex virus thymidine kinase (HSV-TK) and ganciclovir (GCV) with Escherichia coli nitroreductase (Coli.NTR) and 5-(azaridin-1-yl)-2, 4-dinitrobenzamide (CB1954) by a recombinant retrovirus delivery system resulted in a co-operative killing effect in vitro. We constructed a bicistronic adenovirus type 5 (Ad5)-based vector which co-expresses herpes HSV-TK and Coli.NTR under the control of the human telomerase reverse transcriptase (hTERT) promoter and SV40 enhancer. NTR gene expression mediated by an internal ribosome entry site (IRES) was inserted after the hTERT and HSV-TK sequences. Anti-tumor activities of the novel vector, Ad-hT-TK/NTR-enh, combined with prodrugs were evaluated in human breast cancer cells (ZR-75-30, MCF-7) in vitro and in vivo. We showed that expression of HSV-TK and NTR genes by Ad-hT-TK/NTR-enh in combination with GCV and CB1954 resulted in specific and significant cytotoxic effects in breast cancer cells in vitro. The anti-tumor activity of this system was more efficient than that from a single suicide gene, and only slightly lower than by HSV-TK and NTR driven from separate hTERT promoters in vitro and in vivo while the total amount of adenovirus of Ad-hT-TK/NTR-enh was half that of Ad-hT-TK-enh+Ad-hT-NTR-enh. These results suggest that suicide genes HSV-TK and NTR mediated by a single adenovirus vector under the control of an enhanced hTERT promoter results in additive anti-tumor effects and may provide a relatively safe strategy for the treatment of breast cancer by tumor-specific targeting.

Highly sequence-dependent formation of fluorescent silver nanoclusters in hybridized DNA duplexes for single nucleotide mutation identification.

Fluorescent silver nanoclusters were successfully synthesized using hybridized DNA duplexes as capping scaffolds. The formation of these emitters was highly sequence-dependent and could specifically identify a single nucleotide mutation, the sickle cell anemia gene mutation. Furthermore, the identification of single-nucleotide differences using this strategy was extended to more general types of single-nucleotide mismatches.