Network pharmacology integrated with experimental validation revealed potential molecular mechanisms of Camellia nitidissima C. W. Chi in the treatment of lung cancer.

ETHNOPHARMACOLOGICAL RELEVANCE: Camellia nitidissima C.W.Chi (CNC), an ethnomedicine mainly distributed in Southern China's Guangxi Zhuang Autonomous Region, is known as "Panda in plants" and "Camellias Queen" due to its golden blossom. CNC has been applied as a traditional folk medicine in cancer therapy. AIM OF THE STUDY: This study utilized network pharmacology analysis combined with experimental validation to identify the substance basis and potential molecular mechanism of CNC against lung cancer. MATERIALS AND METHODS: The active ingredients of CNC were identified based on published literature. The associated potential targets of CNC in lung cancer treatment were predicted using integrated network pharmacology analysis and molecular docking. The underlying molecular mechanism of CNC in lung cancer were validated in human lung cancer cell lines. RESULTS: A total of 30 active ingredients and 53 targets of CNC were screened. An enrichment analysis of Gene Ontology (GO) revealed that the effects of CNC in lung cancer mainly involve protein binding, regulation of cell proliferation and apoptosis, and signal transduction. KEGG pathways analysis suggested that CNC might exert cancer suppression effects mainly through pathways in cancer, PI3K/AKT signaling pathway. Molecular docking revealed that CNC has high affinity for binding of EGFR, SRC, AKT1, and CCND1 to the key active ingredients including luteolin, kaempferol, quercetin, eriodictyol and 3'4-O-dimethylcedrusin. In in vitro experiments, CNC played the inhibitory roles in lung cancer cells by inducing cell apoptosis, causing G0/G1 and S cell cycle arrest, increasing intracellular ROS levels, and promoting the apoptotic proteins Bax and Caspase-3. Meanwhile, CNC also regulated the expression of core proteins EGFR, SRC, and AKT. CONCLUSION: These results comprehensively clarified the associated substance basis and underlying molecular mechanism of CNC against lung cancer, which would be contributed to develop promising anti-cancer pharmaceuticals or therapeutic approaches for lung cancer therapy.

Identification and characteristic analysis of enhancers across 13 major cancer types.

Enhancers are often mutated and dysregulated in various diseases such as cancer. By integrating the function annotation of the mammalian genome (FANTOM) enhancers expression profiles and RNA-seq data from The Cancer Genome Atlas (TCGA) of 13 cancers and their corresponding para-cancerous tissues, we systematically identified a total of 4702 significantly differentially expressed (DE) enhancers. Furthermore, a total of 1036 DE genes regulated by DE enhancers were identified. It was found that in these 13 cancers, most (61.13%) enhancers were ubiquitously expressed, whereas DE enhancers were more likely to be tissue-specific expressed, and the DE genes regulated by DE enhancers were significantly enriched in cancer-related pathways. Finally, it was manifested that 74 single nucleotide polymorphisms (SNPs) were located in 37 DE enhancers, and these SNPs affected the gain and loss of functional transcription factor binding sites of 758 transcription factors, which were shown to be highly correlated with tumorigenesis and development.

Identification and Analysis of p53-Regulated Enhancers in Hepatic Carcinoma.

Enhancers can act as cis-regulatory elements to control transcriptional regulation by recruiting transcription factors (TFs) in a distance and orientation-independent manner. However, it is still unclear how p53 participates in the enhancer network as TF in hepatic carcinoma under the condition of DNA damage. A total of 14,286 active enhancers were identified through the integration of stable and unstable enhancer RNAs (eRNAs) captured by CAGE and GRO-seq, respectively. Furthermore, 218 p53-bound enhancers (Enhp53) were identified by analyzing p53 ChIP-seq in HepG2 cells after DNA damage. The results showed that the enhancer expression and histone markers of enhancers (H3K4me1, H3K4me2, H3K4me3, H3K9ac, and H3K27ac) revealed significantly higher level on Enhp53 than Enhno-p53 which suggested that p53 participated in regulating enhancer activity and chromatin structure. By analyzing 124 TFs ChIP-seq from ENCODE, 93 TFs were found significantly enriched on Enhp53 such as GATA4, YY1, and CTCF, indicating p53 may co-regulate enhancers with TFs participation. Moreover, significantly differentially expressed 438 miRNAs and 1,264 mRNAs were identified by analyzing small RNA-seq and RNA-seq, and 26 Enhp53-miRNAs and 145 Enhp53-mRNA interactions were identified by the integration of 3D genome data and genomic distance. The functional enrichment analysis showed that these miRNA targets and mRNAs were significantly involved in tumor biological processes and signaling pathways such as DNA replication, p53 signaling pathway, hepatitis B, focal adhesion, etc. The above results indicated that p53 participated in regulating enhancer network in hepatic carcinoma and Enhp53 exhibited significantly different characteristics with Enhno-p53.

Genome-Wide Identification and Analysis of Enhancer-Regulated microRNAs Across 31 Human Cancers.

Enhancers are cis-regulatory DNA elements that positively regulate the transcription of target genes in a tissue-specific manner, and dysregulation of target genes could lead to various diseases, such as cancer. Recent studies have shown that enhancers can regulate microRNAs (miRNAs) and participate in their biological synthesis. However, the network of enhancer-regulated miRNAs across multiple cancers is still unclear. Here, a total of 2,418 proximal enhancer-miRNA interactions and 1,280 distal enhancer-miRNA interactions were identified through the integration of genomic distance, co-expression, and 3D genome data in 31 cancers. The results showed that both proximal and distal interactions exhibited a significant cancer type-specific feature trend at the tissue level rather than at the single-cell level, and there was a noteworthy positive correlation between the expression of the miRNA and the number of enhancers regulating the same miRNA in most cancers. Furthermore, we found that there was a high correlation between the formation of enhancer-miRNA pairs and the expression of enhancer RNAs (eRNAs) whether in distal or proximal regulation. The characteristics analysis showed that miRes (enhancers that regulated miRNAs) and non-miRes presented significant differences in sequence conservation, guanine-cytosine (GC) content, and histone modification signatures. Notably, GC content, H3K4me1, and H3K36me3 were present differently between distal and proximal regulation, suggesting that they might participate in chromosome looping of enhancer-miRNA interactions. Finally, we introduced a case study, enhancer: chr1:1186391-1186507 ∼ miR-200a was highly relevant to the survival of thyroid cancer patients and a cis-eQTL SNP on the enhancer affected the expression of the TNFRSF18 gene as a tumor suppressor.

D-4F Ameliorates Contrast Media-Induced Oxidative Injuries in Endothelial Cells via the AMPK/PKC Pathway.

Endothelial dysfunction is involved in the pathophysiological processes of contrast media (CM)-induced acute kidney injury (CI-AKI) after vascular angiography or intervention. Previous study found that apolipoprotein A-I (apoA-I) mimetic peptide, D-4F, alleviates endothelial impairments via upregulating heme oxygenase-1 (HO-1) expression and scavenging excessively generated reactive oxygen species (ROS). However, whether D-4F could ameliorate oxidative injuries in endothelial cells through suppressing ROS production remains unclear. In this study, a representative nonionic iodinated CM, iodixanol, was chosen for the in vitro and in vivo studies. Endothelial cell viability was assayed using micrographs, lactate dehydrogenase (LDH) activity, and cell counting kit-8 (CCK-8). Apoptosis was detected using flow cytometry analysis and caspase-3 activation. Endothelial inflammation was tested using monocyte adhesion assay and adhesion molecule expression. ROS production was detected by measuring the formation of lipid peroxidation malondialdehyde (MDA) through the thiobarbituric acid reactive substance (TBARS) assay. Peroxynitrite (ONOO⁻) formation was tested using the 3-nitrotyrosine ELISA kit. Iodixanol impaired cell viability, promoted vascular cell adhesion molecule-1 (VCAM-1) and intercellular cell adhesion molecule-1 (ICAM-1) expression, and induced cell apoptosis in human umbilical vein endothelial cells (HUVECs). However, D-4F mitigated these injuries. Furthermore, iodixanol induced the phosphorylation of protein kinase C (PKC) beta II, p47, Rac1, and endothelial nitric oxide synthase (eNOS) at Thr495, which elicited ROS release and ONOO⁻ generation. D-4F inhibited NADPH oxidase (NOX) activation, ROS production, and ONOO⁻ formation via the AMP-activated protein kinase (AMPK)/PKC pathway. Additionally, after an intravascular injection of iodixanol in Sprague Dawley rats, iodixanol induced a remarkable inflammatory response in arterial endothelial cells, although significant apoptosis and morphological changes were not observed. D-4F alleviated the vessel inflammation resulting from iodixanol in vivo. Collectively, besides scavenging ROS, D-4F could also suppress ROS production and ONOO⁻ formation through the AMPK/PKC pathway, which ameliorated oxidative injuries in endothelial cells. Hence, D-4F might serve as a potential agent in preventing CI-AKI.

Comparison of Mechanisms of Endothelial Cell Protections Between High-Density Lipoprotein and Apolipoprotein A-I Mimetic Peptide.

Apolipoprotein A-I (apoA-I) mimetic peptide, D-4F, exhibits anti-atherogenic effects similar to high-density lipoprotein (HDL). However, it remains elusive whether D-4F and HDL share similar molecular mechanisms underlying anti-atherogenic effects and endothelial cell protections. We here compared the metabolic changes in endothelial cells induced by D-4F and HDL against oxidized low-density lipoprotein (ox-LDL), which may be of benefit to understanding the protective mechanisms of HDL and D-4F. Functional assays, including wound healing, transwell migration, and tube formation, were used to evaluate the pro-angiogenic effects of HDL and D-4F. NMR-based metabolomic analysis was employed to explore the protective mechanisms underlying HDL and D-4F. Partial least-squares discriminant analysis (PLS-DA) was performed to assess metabolic profiles, and orthogonal PLS-DA (OPLS-DA) was carried out to identify characteristic metabolites. Moreover, significantly altered metabolic pathways were also analyzed. We found that ox-LDL impaired the migration and tube formation of endothelial cells. Metabolomic analysis showed that ox-LDL triggered oxidative stress, impaired glycolysis, and enhanced glycerophospholipid metabolism. Both HDL and D-4F improved the migration and angiogenesis of endothelial cells, alleviated oxidative stress, and ameliorated disordered glycolysis impaired by ox-LDL. Strikingly, HDL partially attenuated the disturbed glycerophospholipid metabolism, whereas D-4F did not show this effect. In summary, although D-4F shared the similar protective effects with HDL on the migration and angiogenesis of endothelial cells, it could not deduce the molecular mechanisms of HDL completely. Nevertheless, D-4F possesses the potentiality to be exploited as clinically applicable agent for endothelial cell protection and cardiovascular disease treatment.

Glycation of high-density lipoprotein triggers oxidative stress and promotes the proliferation and migration of vascular smooth muscle cells.

BACKGROUND: In type 2 diabetes mellitus (T2DM), high-density lipoprotein (HDL) impairs its anti-atherogenic properties and even develops to a pro-inflammatory and pro-atherogenic phenotype because of abnormal compositions and modifications. In this study, we examined the effects and the related mechanisms of glycation of HDL on the proliferation and migration of vascular smooth muscle cells (VSMCs). METHODS & RESULTS: Glycated HDL (G-HDL) was modified with D-glucose (25 mmol/L) in vitro. Diabetic HDL (D-HDL) was isolated from T2DM patients. Rat VSMCs were isolated from the thoracic aortas. Human VSMCs were obtained from ScienCell Research Laboratories. Alpha-actin was detected through immunofluorescence. VSMC proliferation was assayed by Cell Count. VSMC migration was determined by transwell chamber and scratch-wound assay. Intracellular reactive oxygen species (ROS) was detected based on ROS-mediated 2',7'-dichlorofluorescein (DCFH-DA) fluorescence. Compared to native HDL (N-HDL), G-HDL remarkably promoted VSMC proliferation and migration in the dose and time-dependent manners. In addition, G-HDL enhanced ROS generation in VSMCs. However, the ROS scavenger, N-acetylcysteine, efficiently decreased ROS production and subsequently inhibited the proliferation of VSMCs induced by G-HDL. Similarly, D-HDL from T2DM patients also promoted ROS release and VSMC proliferation and migration. CONCLUSIONS: HDL either glycated in vitro or isolated from T2DM patients triggered VSMC proliferation, migration, and oxidative stress. These results might partly interpret the higher morbidity of cardiovascular disease in T2DM patients.

The apolipoprotein A-I mimetic peptide, D-4F, restrains neointimal formation through heme oxygenase-1 up-regulation.

D-4F, an apolipoprotein A-I (apoA-I) mimetic peptide, possesses distinctly anti-atherogenic effects. However, the biological functions and mechanisms of D-4F on the hyperplasia of vascular smooth muscle cells (VSMCs) remain unclear. This study aimed to determine its roles in the proliferation and migration of VSMCs. In vitro, D-4F inhibited VSMC proliferation and migration induced by ox-LDL in a dose-dependent manner. D-4F up-regulated heme oxygenase-1 (HO-1) expression in VSMCs, and the PI3K/Akt/AMP-activated protein kinase (AMPK) pathway was involved in these processes. HO-1 down-regulation with siRNA or inhibition with zinc protoporphyrin (Znpp) impaired the protective effects of D-4F on the oxidative stress and the proliferation and migration of VSMCs. Moreover, down-regulation of ATP-binding cassette transporter A1 (ABCA1) abolished the activation of Akt and AMPK, the up-regulation of HO-1 and the anti-oxidative effects of D-4F. In vivo, D-4F restrained neointimal formation and oxidative stress of carotid arteries in balloon-injured Sprague Dawley rats. And inhibition of HO-1 with Znpp decreased the inhibitory effects of D-4F on neointimal formation and ROS production in arteries. In conclusion, D-4F inhibited VSMC proliferation and migration in vitro and neointimal formation in vivo through HO-1 up-regulation, which provided a novel prophylactic and therapeutic strategy for anti-restenosis of arteries.

The apolipoprotein A-I mimetic peptide, D-4F, alleviates ox-LDL-induced oxidative stress and promotes endothelial repair through the eNOS/HO-1 pathway.

Apolipoprotein A-I (apoA-I) mimetic peptide exerts many anti-atherogenic properties. However, the underlying mechanisms related to the endothelial protective effects remain elusive. In this study, the apoA-I mimetic peptide, D-4F, was used. Proliferation assay, wound healing, and transwell migration experiments showed that D-4F improved the impaired endothelial proliferation and migration resulting from ox-LDL. Endothelial adhesion molecules expression and monocyte adhesion assay demonstrated that D-4F inhibited endothelial inflammation. Caspase-3 activation and TUNEL stain indicated that D-4F reduced endothelial cell apoptosis. A pivotal anti-oxidant enzyme, heme oxygenase-1 (HO-1) was upregulated by D-4F. The Akt/AMPK/eNOS pathways were involved in the expression of HO-1 induced by D-4F. Moreover, the anti-oxidation, pro-proliferation, and pro-migration capacities of D-4F were diminished by the inhibitors of both eNOS (L-NAME) and HO-1 (Znpp). Additionally, downregulation of ATP-binding cassette transporter A1 (ABCA1) by siRNA abolished the activation of Akt, AMPK and eNOS, and reduced the upregulation of HO-1 triggered by D-4F. Furthermore, D-4F promoted the reendothelialization of injured intima in carotid artery injury model of C57BL/6J mice in vivo. In summary, these findings suggested that D-4F might be a powerful candidate in the protection of endothelial cells and the prevention of cardiovascular disease (CVD).

Protective efficacy of PLGA microspheres loaded with divalent DNA vaccine encoding the ompA gene of Aeromonas veronii and the hly gene of Aeromonas hydrophila in mice.

In the present study, poly (lactic-co-glycolic) acid (PLGA) was used as a carrier for a divalent fusion DNA vaccine encoding the Aeromonas veronii outer membrane protein A (ompA) and Aeromonas hydrophila hemolysins (hly) protein. The recombinant pET-28a-ompA-hly was constructed by inserting the ompA gene and hly gene into a pET-28a expression vector. Loading of ompA-hly antigen module on PLGA microspheres were accomplished by water-in-oil-in-water (W/O/W) encapsulation. The molecular weight and specificity of pET-28a-ompA-hly were detected by dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting. The microspheres showed an average particle size of 100-150 µm and a loading efficiency (LE) of 68.8%. Mice received ompA-hly antigen-loaded PLGA microspheres by intraperitoneal or intragastric administration mounted strong and sustained IgG response, which was significantly higher (p<0.05) than those achieved by pET-28a-ompA-hly antigen alone. OmpA-hly antigen-loaded PLGA microsphere vaccine uniquely conferred a long lasting (30 days) sterile immunity against challenge infection. Results indicated that ompA-hly antigen-loaded PLGA microsphere vaccine is a qualified candidate vector system for sterile protective immunity against A. hydrophila and A. veronii infections.

[Construction and immunogenicity of a genetic engineered strain expressing nontoxic ST1-LT(B)-alpha-beta fusion protein against diarrhea of piglet].

We constructed a recombinant strain BL21 (DE3) (pETST3LTBalphabeta) including ST1-LT(B)-alpha-beta fusion gene via molecular technology. The SDS-PAGE and Western blotting indicated that the ST1-LT(B)-alpha-beta fusion protein was highly expressed in Escherichia coli and the molecular weight of the fusion protein was about 110 kD. The recombinant strain was induced in different concentrations of lactose and different aeration rate. The optimal culture conditions in 20 L fermentor were 1% inoculation (V/V), initial aeration 5 L/min, 0.03 mol/L lactose addition 3 hours after inoculation, and increased the aeration to 12.5 L/min for the following 6 hours. The fusion protein was about 38.53% of total cellular protein. It was nontoxic, immunogenic and protective against enterotoxigenic E. coli and Clostridium perfringens infection. The constructed recombinant strain BL21 (DE3) (pETST3LTBalphabeta) could serve as a candidate vaccine strain against diarrhea of piglet.