Efficacy and potential mechanism of atherosclerosis prevention by the active components of leech based on network pharmacology combined with animal experiments.

Introduction: Leeches are flesh-eating and bloodsucking parasitic worms. They are being used as a traditional Chinese medicine for centuries in activating blood and dissolving statis, dreging the meridims and tick. Hirudin, an active peptide product present in leech, has blood anticoagulant property and can assist in the treatment of thrombosis and diseases related to blood circulation. The efficacy and potential mechanism of action of leeches in such diseases should be further explored. Materials and methods: First, network pharmacology was used to screen the predicted potential targets of the active constituents of leech and AS. The common targets of the active constituents of leech and AS were obtained using Venn diagram. Further, the drug-active-constituent-target network diagram, protein-protein interaction, and GO and KEGG pathway enrichment analyses were used to construct the active-constituent-AS target-pathway network diagram. Subsequently, the protein-drug molecule docking model was drawn. Finally, the results of network pharmacology were validated using a mouse model of AS. Results: In total, 34 active constituents of leech and 1172 AS-related gene targets were selected, took the drug action targets and potential disease targets to get the common targets, and took the top 10 of degree value as the main active constituents for the treatment of atherosclerosis. There were 89 common targets and 12 core targets. The main targets included MAPK, EGFR, PIK3CB, etc. Potential regulatory pathways included cancer pathways, EGFR tyrosine kinase inhibitor resistance, Rap1 signaling pathway, PPAR signaling pathway, PI3K-Akt signaling pathway, C-type lectin receptor signaling pathway, and AGE-RAGE signaling pathway in diabetic complications. Animal experiments using mouse model of AS confirmed that AS plaques were smaller after treatment with leeches. SRC level was measured using western blotting. Expression of SRC in myocardial tissue was remarkably lower in the mice treated with leech than in the mice from model group fed on high-fat chow. Conclusions: To the best of our knowledge, this is the first study to explore the mechanism of action of the active components of leech in AS prevention. The active components of leeches play a coordinated role in preventing AS through multicomponent, multitarget, and multichannel mechanism of action related to inflammatory response, oxidative stress, and lipid metabolism. This study provided a reference for subsequent cellular and animal experiments.

The association between atherosclerosis and nonalcoholic fatty liver disease.

Atherosclerosis (AS) is closely related to nonalcoholic fatty liver disease (NAFLD), which promotes and exacerbates the development of AS. However, it is uncertain how the precise underlying mechanism occurs. Here, we attempted to further explore the association underlying atherosclerosis and nonalcoholic fatty liver disease through integrated bioinformatics analysis. Microarray data for atherosclerosis and nonalcoholic fatty liver disease were retrieved from the Gene Expression Omnibus (GEO) database. Weighted gene co-expression network analysis (WGCNA) was used to identify the genes related to atherosclerosis and nonalcoholic fatty liver disease showing co-expression. Additionally, the common gene targets associated with atherosclerosis and nonalcoholic fatty liver disease were also analyzed and screened using data from 3 public databases [comparative toxicogenomics database (CTD), DISEASES, and GeneCards]. The Gene Ontology (GO) enrichment analysis and the Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis were performed using Metascape R, respectively. The protein-protein interaction networks (PPI) network was constructed using Cytoscape. According to the results of an analysis of common genes, matrix metalloproteinase 9 (MMP9) is co-expressed up-regulated in AS and NAFLD and is enriched in inflammatory and immune-related collaterals. Consequently, MMP9 may work together through immunity and inflammation to treat AS and NAFLD and may be a potential therapeutic target in the future. The findings of this study provide new insights into the shared association between AS and NAFLD. MMP9 is co-expressed up-regulated in AS and NAFLD, which be able to reveal the presence of co-expressed genes in atherosclerosis and NAFLD.

LncRNA RASSF8-AS1 knockdown displayed antiproliferative and proapoptotic effects through miR-188-3p/ATG7 pathway in ox-LDL-treated vascular smooth muscle cells.

Background: Long noncoding RNA (lncRNA)-mediated changes in gene expression contribute to atherosclerosis (AS) development. However, the roles of numerous lncRNAs in AS have not been fully elucidated. Here, we aimed to investigate the potential role of lncRNA RASSF8-AS1 (RASSF8-AS1) in autophagy of human aortic vascular smooth muscle cells (HA-VSMCs). Methods: RASSF8-AS1 expression in patients with AS was extracted from the Gene Expression Omnibus (GEO) database. RASSF8-AS1 and microRNA-188-3p (miR-188-3p) expression was analyzed in 20 enrolled patients with AS. HA-VSMCs were treated with oxidized low-density lipoprotein (ox-LDL) (25, 50, 75, and 100 µg/mL) for 24 h. Loss- or gain-of-function of RASSF8-AS1, miR-1883p, and autophagy-related 7 (ATG7) was studied using the transfected HA-VSMCs. Cell viability was assessed using Cell Counting Kit-8 (CCK-8). Apoptosis was detected with annexin V-fluorescein isothiocyanate (FITC) and propidium iodide (PI). Relative luciferase reporter assay was used to confirm the targeting relationship of miR-188-3p to RASSF8-AS1 or ATG7. Gene expression was detected by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot. Results: RASSF8-AS1 was enriched in the serum of patients with AS and ox-LDL-treated HA-VSMCs. Ox-LDL induced proliferation and autophagy while inhibiting the apoptosis of HA-VSMCs, which was abated by RASSF8-AS1 knockdown. RASSF8-AS1 downregulated miR-188-3p of ox-LDL-treated HA-VSMCs. RASSF8-AS1 knockdown caused an increase in miR-188-3p, which inhibited proliferation and autophagy and induced the apoptosis of ox-LDL-treated HA-VSMCs. miR-188-3p inhibited ATG7 expression in ox-LDL-treated HA-VSMCs. RASSF8-AS1 elevated ATG7 and induced autophagy through sponging miR-188-3p in ox-LDL-treated HA-VSMCs. Conclusions: RASSF8-AS1 regulated autophagy by targeting miR-188-3p, a messenger RNA-binding miRNA that increases ATG7 level, which may be a new target molecule for the prevention and prognosis of AS.

[Network Meta-analysis of Chinese patent medicine containing Hirudo in treatment of atherosclerosis].

This study aimed to evaluate the efficacy and safety of Chinese patent medicines containing Hirudo in the treatment of atherosclerosis(AS) by network Meta-analysis, and to provide evidence-based reference for clinical treatment of AS. The clinical randomized controlled trial(RCT) on the treatment of atherosclerosis with Chinese patent medicines containing Hirudo were searched in CNKI, Wanfang, VIP, SinoMed, PubMed and EMbase from the establishment of the databases to July 1, 2022. And data extraction and quality assessment of the included RCT was performed according to the Cochrane standards. Stata 17 and ADDIS 1.16.5 were then used for Bayesian model network Meta-analysis. Finally, 67 RCTs with a total sample size of 6 826 cases were included, 3 569 cases in the experimental group and 3 257 cases in the control group, involving three oral Chinese patent medicines. Network Meta-analysis showed that in terms of reducing intima-media thickness(IMT), the top three Chinese patent medicines were Tongxinluo Capsules+sta-tins>Maixuekang Capsules+statins>Maixuekang Capsules. In terms of reducing plaque area, the top one was Maixuekang Capsules+sta-tins, and the other Chinese patent medicines had similar efficacy. For lowering AS Crouse scores, the top three were Maixuekang Capsules>Tongxinluo Capsules+statins>Naoxintong Capsules. For decreasing plaque number, the top three were Naoxintong Capsules+sta-tins>Tongxinluo Capsules+statins>Tongxinluo Capsules. With regard to adverse reactions/events, Naoxintong Capsules+statins had the lo-west incidence. In conclusion, in Chinese patent medicines containing Hirudo for the treatment of AS, Tongxinluo Capsules+statins, Maixuekang Capsules, Maixuekang Capsules+statins, and Naoxintong Capsules+statins were the primary choices to reduce IMT, AS Crouse scores, plaque area, and plaque number, respectively. The efficacy of Chinese patent medicines containing Hirudo with or without statins was more significant than that of statins alone in the four outcome indexes. Additionally, the treatment of AS should be evaluated comprehensively, and attention should be paid to Chinese patent medicines or their combination with western medicine, to optimize the treatment effect and minimize adverse reactions as the benchmark.

Construction of lncRNA and mRNA co-expression network associated with nasopharyngeal carcinoma progression.

Nasopharyngeal carcinoma is a type of head and neck cancer with a high incidence in men. In the past decades, the survival rate of NPC has remained around 70%, but it often leads to treatment failure due to its distant metastasis or recurrence. The lncRNA-mRNA regulatory network has not been fully elucidated. We downloaded the NPC-related gene expression datasets GSE53819 and GSE12452 from the Gene Expression Omnibus database; GSE53819 included 18 NPC tissues and 18 normal tissues, and GSE12452 included 31 NPC tissues and 10 normal tissues. Weighted gene co-expression network analysis was performed on mRNA and lncRNA to screen out modules that were highly correlated with tumor progression. The two datasets were subjected to differential analysis after removing batch effects, and then Venn diagrams were used to screen for overlapping genes in the module genes and differential genes. The lncRNA-mRNA co-expression network was then constructed, and key mRNAs were identified by MCODE analysis and expression analysis. GSEA analysis and qRT-PCR were performed on key mRNAs. Through a series of analyses, we speculated that BTK, CD72, PTPN6, and VAV1 may be independent predictors of the prognosis of NPC patients.Taken together, our study provides potential candidate biomarkers for NPC diagnosis, prognosis, or precise treatment.

Nutrient Deprivation Coupled with High Light Exposure for Bioactive Chrysolaminarin Production in the Marine Microalga Isochrysis zhangjiangensis.

Chrysolaminarin, a kind of water-soluble bioactive ß-glucan produced by certain microalgae, is a potential candidate for food/pharmaceutical applications. This study identified a marine microalga Isochrysis zhangjiangensis, in which chrysolaminarin production was investigated via nutrient (nitrogen, phosphorus, or sulfur) deprivations (-N, -P, or -S conditions) along with an increase in light intensity. A characterization of the antioxidant activities of the chrysolaminarin produced under each condition was also conducted. The results showed that nutrient deprivation caused a significant increase in chrysolaminarin accumulation, though this was accompanied by diminished biomass production and photosynthetic activity. -S was the best strategy to induce chrysolaminarin accumulation. An increase in light intensity from 80 (LL) to 150 (HL) µE·m-2·s-1 further enhanced chrysolaminarin production. Compared with -N, -S caused more suitable stress and reduced carbon allocation toward neutral lipid production, which enabled a higher chrysolaminarin accumulation capacity. The highest chrysolaminarin content and concentration reached 41.7% of dry weight (%DW) and 632.2 mg/L, respectively, under HL-S, with a corresponding productivity of 155.1 mg/L/day achieved, which exceeds most of the photoautotrophic microalgae previously reported. The chrysolaminarin produced under HL-N (Iz-N) had a relatively competitive hydroxyl radical scavenging activity at low concentrations, while the chrysolaminarin produced under HL-S (Iz-S) exhibited an overall better activity, comparable to the commercial yeast ß-glucan, demonstrating I. zhangjiangensis as a promising bioactive chrysolaminarin producer from CO2.

Process of fetal head descent as recorded by ultrasonography: How does this compare with the conventional first stage of labor?

OBJECTIVE: To construct an ultrasound partogram using serial transperineal sonographic measurements of the angle of fetal head progression during the first stage of labor, and to compare it with a conventional partogram based on digital vaginal examinations. METHODS: Between 2017 and 2018, a prospective cohort study at Drum Tower Hospital, Nanjing, China, recruited 375 nulliparous women with singleton pregnancy and spontaneous onset of labor at 37 or more gestational weeks. Transperineal ultrasound scans were performed to measure the angle of progression (AoP) every 0.5-1 h until the second stage. Vaginal examinations were also used to measure cervical dilatation. Repeated-measures analysis was used to generate labor curves. RESULTS: The labor curve generated by AoP had a pattern similar to that based on cervical dilatation. There was an initial slow period lasting approximately 5.5 h until the cervical dilatation or AoP reached the inflection point (4 cm and 119°, respectively), followed by a second, more rapid period, lasting approximately 2.5 h. CONCLUSION: Based on ultrasound data, it was feasible to construct an "angle of progression partogram" of the first stage of labor, which was similar in pattern to the partogram based on cervical dilatation measured in the same cohort.

Fine-tuned regulation of photosynthetic performance via γ-aminobutyric acid (GABA) supply coupled with high initial cell density culture for economic starch production in microalgae.

Microalgal starch is considered as renewable and sustainable feedstock for biofuels and biorefinery. High cell density culture is favourable for photoautotrophic starch production in microalgae in the aspects of productivity and economy, but it often encounters low starch content or extra stress exposure that limits the production. This study aimed to economically enhance photosynthetic starch production from CO2 fixation in a green microalga Tetraselmis subcordiformis by regulating photosynthetic stress status with a signalling molecule γ-aminobutyric acid (GABA) combined with the application of high initial cell density culture. By increasing initial cell density (ICD) from the normal of 1.1 g L-1 (NICD) to as high as 2.8 g L-1 (HICD), the starch content, yield, and theoretical productivity were improved by 7%, 63%, and 42%, respectively. The addition of GABA under HICD resulted in 14%, 19%, and 26% of further enhancement in starch content, yield, and theoretical productivity, respectively. GABA exhibited distinct regulatory mechanisms on photosynthesis and stress status under HICD relative to NICD. GABA augmented excessive light energy absorption and electron transfer through photosystem II that reinforced the photoinhibition under NICD, while alleviated the stress reversely under HICD, both of which facilitated starch production by enabling a suitable stress status while simultaneously maintaining a sufficient photosynthetic activity. The increase of ICD and/or GABA supply particularly boosted amylopectin accumulation, leading to the changes in starch composition and was more favourable for fermentation-based biofuels production. Preliminary techno-economic analysis showed that the highest net extra benefit of 9.64 $ m-3 culture could be obtained under HICD with 2.5 mM GABA supply where high starch content (62%DW) and yield (2.5 g L-1) were achieved. The combined HICD-GABA regulation was a promising strategy for economic starch production from CO2 by microalgae for sustainable biomanufacturing.

Translocator protein 18 kDa: a potential therapeutic biomarker for post traumatic stress disorder.

Post traumatic stress disorder (PTSD) is widely regarded as a stress-related and trauma disorder. The symptoms of PTSD are characterized as a spectrum of vulnerabilities after the exposure to an extremely traumatic stressor. Considering as one of complex mental disorders, little progress has been made toward its diagnostic biomarkers, despite the involvement of PTSD has been studied. Many studies into the underlying neurobiology of PTSD implicated the dysfunction of neurosteroids biosynthesis and neuorinflammatory processes. Translocator protein 18 kDa (TSPO) has been considered as one of the promising therapeutic biomarkers for neurological stress disorders (like PTSD, depression, anxiety, et al) without the benzodiazepine-like side effects. This protein participates in the formation of neurosteroids and modulation of neuroinflammation. The review outlines current knowledge involving the role of TSPO in the neuropathology of PTSD and the anti-PTSD-like effects of TSPO ligands.

Targeting HER2-positive gastric cancer with a novel 18F-labeled ZHER2:342 probe.

To realize the diagnosis of HER2-positive gastric cancer via PET imaging, herein, a new kind of 18F-labeled HER2 affibody probe was created; the bifunctional maleimide derivative 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA-MAL) was first coupled to a polypeptide, and the resulting compound was subsequently labeled with the 18FAl complex. The binding characteristics of the probe were assessed using both in vitro studies and in vivo microPET imaging and biodistribution experiments. Immunohistochemical staining was performed to confirm the expression level of HER2 in the studied cell lines and tumors. The probe was successfully produced with the radiochemical purity of more than 95%. The NCI N87 cell-associated radioactivity was 19.31 ± 1.01% AD, and it decreased to 0.83 ± 0.04% AD per 106 cells after blocking HER2 as early as 15 minutes post-incubation (p < 0.05). A competition binding assay between radiolabeled and non-radioactive affibody molecules with NCI N87 indicated that the IC50 was 8.10 nM. The microPET imaging and biodistribution of human gastric cancer xenografts demonstrated that the probe could specifically accumulate in tumors at early time points. Protein detection confirmed a strong HER2 expression in NCIN87 and a weak HER2 expression in SGC7901. In conclusion, 18FAl-NOTA-MAL-Cys-GGGRDN(M0)-ZHER2:342 was successfully prepared via a one-step method. The favorable preclinical data showed specific and effective tumor targeting capacity of the proposed probe; this revealed that the probe proposed herein might have potential application in gastric cancer imaging.

The complete chloroplast genome of an endangered species Cymbidium mastersii (Orchidaceae).

Cymbidium mastersii Griff. & Lindl. is an endangered orchid. In this study, we report the complete chloroplast (cp) genome sequence and the cp genome features of C. mastersii. The cp genome sequence of C. mastersii was 155,362 bp in length. It included one large single-copy region (LSC, 84,465 bp), one small single-copy region (SSC, 20,647 bp), and two inverted repeat regions (IRs, 25,125 bp). The cp genome encoded 130 genes, of which 107 were unique genes (80 protein-coding genes, 23 tRNAs, and 4 rRNAs). The maximum-likelihood phylogenetic analysis showed that C. mastersii was a sister of C. erythraeum and C. nanulum.

Complete chloroplast genome of Dendrobium thyrsiflorum (Orchidaceae).

Dendrobium thyrsiflorum H. G. Reichenbach ex André is an endemic herb with ornamental and medicinal orchid value distributed in Southeast of Yunnan of China. Here, we report and characterize the complete chloroplast (cp) genome sequence of D. thyrsiflorum in order to provide genomic resources helpful for its identification, conservation and utilization. The complete cp genome of D. thyrsiflorum is 160,123 bp, including one large single-copy region (LSC, 88,001), one small single-copy region (SSC, 21,142), and two inverted repeat regions (IRs, 25,490). The cp genome contains 143 genes, consisting of 110 unique genes (80 protein-coding genes, 26 tRNAs, and 4 rRNAS). The phlyogenetic relationships show that D. thyrsiflorum is closely related to other species of Dendrobium.

The complete chloroplast genome of Dendrobium harveyanum (Orchidaceae).

Dendrobium harveyanum is an endangered species of Orchidaceae. Here we report the complete chloroplast (cp) genome sequence and the cp genome features of D. harveyanum. The complete cp genome sequence of D. harveyanum is 157,292 bp in length and presented a typical quadripartite structure including one large single-copy region (LSC, 86,583 bp), one small single-copy region (SSC, 19,449 bp), and two inverted repeat regions (IRs, 25,630 bp each). The cp genome encoded 138 genes, of which 120 were unique genes. The phylogenetic relationships show that D. harveyanum is closely related to other species in Dendrobium.

The complete chloroplast genome of Dendrobium longicornu (Orchidaceae).

Dendrobium longicornu Lindl is an epiphytic orchid with significant ornamental values. Here, we report the first complete chloroplast genome of D. longicornu. The complete chloroplast (cp) genome sequence of D. longicornu is 160,024 bp in length and consisted of two inverted repeats (IRs, 25,403 bp), which were separated by a large single copy region (LSC, 88,075 bp) and a small single copy region (SSC, 21,143 bp). The cp genome encoded 142 genes, of which 110 were unique genes (80 protein-coding genes, 26 tRNAs and 4 rRNAs). Phylogenetic analysis showed that D. longicornu clustered together with D. ellipsophy.

Association of astragaloside IV-inhibited autophagy and mineralization in vascular smooth muscle cells with lncRNA H19 and DUSP5-mediated ERK signaling.

Defective autophagy in vascular smooth muscle cells (VSMCs) is the principal cause of atherosclerosis. This study aimed to investigate the effect of astragaloside IV (AS-IV) on VSMCs autophagy. In vivo, ApoE-/- mice were fed with high-fat diet ad libitum for eight weeks, with or without AS-IV (25 mg/kg, daily). In vitro, human VSMCs were cultured and treated with ß-Glycerophosphate (10 mmol/L) and AS-IV (50 µg/ml). VSMCs autophagy, mineralization, expression of p-ERK1/2, p-mTOR, and autophagy-related proteins (LC3 II/I, p62, and Beclin 1) were detected. Increased autophagy and mineralization was observed in VSMCs in thoracic aorta of mice and in in vitro VSMCs model of atherosclerosis. AS-IV administration attenuated the autophagy and mineralization in VSMCs. Reverse expression profiles of H19 and DUSP5 were observed. AS-IV inhibited DUSP5 and autophagy-related proteins and increased expression of H19, level of p-ERK1/2 and p-mTOR. Further, autophagy and mineralization level in VSMCs were in line with DUSP5 expression level, but in contrast to H19, p-ERK1/2, and p-mTOR profiles. We demonstrated that AS-IV could attenuate autophagy and mineralization of VSMCs in atherosclerosis, which may be associated with H19 overexpression and DUSP5 inhibition.

Cytoprotective effects of paeoniflorin are associated with translocator protein 18 kDa.

Paeoniflorin (PF) is one of the important active components in peony that are known to produce the neuroprotective effects. However, the involved cytoprotective factors on brain astrocytes are remain unclear. Translocator protein 18 kDa (TSPO) and its downstream neurosteroids biosynthesis play a significant role in cytoprotection. Based on these, the role of TSPO and neurosteroids biosynthesis in the cytoprotective effects of PF is evaluated. The astrocyte cells were cultured and AC-5216 (TSPO ligand) was selected as the positive control drug. The cytoprotective effects of PF and the levels of neurosteroids were quantified by water-soluble tetrazolium assay and enzyme linked immunosorbent assay, respectively. The cytoprotective activities of PF were relevant to neurosteroids (e.g. progsterone and allopregnanolone) biosynthesis, while these effects were totally blocked by PK11195, trilostane and finasteride, respectively. In summary, the cytoprotective effects of PF maybe mediated by TSPO and neurosteroids biosynthesis. The findings may provide the new insights into the cytoprotective effects of PF.

Oleanolic acid protects against pathogenesis of atherosclerosis, possibly via FXR-mediated angiotensin (Ang)-(1-7) upregulation.

Atherosclerosis, the leading cause of cardiovascular diseases in the world, is a chronic inflammatory disorder characterized by the dysfunction of arteries. Oleanolic acid (OA) is a bioactive nature product which exists in various plants and herbs. Previous studies have demonstrated that OA was involved in numerous of biological processes, including atherosclerosis. However, the exact mechanisms of the anti-atherosclerosis effects of OA remain unknown. Here, in our study, we analyzed the effects and possible underlying mechanisms of OA in atherosclerosis depending a cell model and an animal model of atherosclerosis. Human umbilical vein endothelial cells (HUVECs) were treated with oxidized low-density lipoprotein (ox-LDL, 100 µg/mL) for 24 h to establish an atherosclerotic cell model. New Zealand white (NZW) rabbits were fed with high-fat (HF) diets for three months to establish an atherosclerotic animal model. Then, cell viability and expression of cytokines (ANG, NO, eNOS, IL-1ß, TNF-α, and IL-6) were measured with CCK-8 assay and ELISA kits, cell apoptosis and cell cycle distribution were analyzed by flow cytometry in the atherosclerotic cell model. Results showed that ox-LDL induced effects of anti-proliferation, cytokines alterations, and cell apoptosis were abolished by the application of OA or Ang (1-7). Further study indicated that OA increased the expression of ANG by upregulating the FXR expression in the ox-LDL induced HUVECs arthrosclerosis model. And the in vivo experiment in the HF diet induced animal model suggested that OA may inhibit the development of atherosclerosis. The atherosclerosis of aortas was assessed by Hematoxylin Eosin (HE), Oil Red O and Picrosirius Red staining; the expression levels of total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C), and high density lipoprotein cholesterol (HDL-C) were determined by the fully automatic biochemical analyzer, in the atherosclerotic animal model. All the results showed that OA treatment improved the cell viability in the cell model, inhibited the atherosclerosis development in the animal model. OA play as an anti-atherosclerosis agent in both the cell model and animal model by upregulating the production of Angiotensin (Ang)-(1-7) through FXR.

PET of HER2 Expression with a Novel 18FAl Labeled Affibody.

Background: Human epidermal growth factor receptor type 2 (HER2) is abundant in a wide variety of tumors and associated with the poor prognosis. Radiolabeled affibodies are potential candidates for detecting HER2-positive lesions. However, laborious multiple-step synthetic procedure and high abdomen background may hinder the widespread use. Herein, cysteinylated ZHER2:342 modified with a new hydrophilic linker (denoted as MZHER2:342) was designed and labeled using 18FAl-NOTA strategies. The biologic efficacy of the novel tracer and its feasibilities for in vivo monitoring HER2 levels were also investigated in xenograft models with different HER2 expressions. Method: MZHER2:342 was conjugated with MAL-NOTA under standard reaction conditions. The affibody molecule was then radiolabeled with 18FAl complex. The binding specificity of the tracer, 18FAl-NOTA-MAL-MZHER2:342, with HER2 was primarily characterized via in vitro studies. MicroPET imaging were performed in nude mice bearing tumors (SKOV-3, JIMT-1 and MCF-7) after injection. The HER2 levels of xenografts were determined using Western blotting analysis. Results:18FAl-NOTA-MAL-MZHER2:342 can be efficiently produced within 30 min with a non-decaycorrected yield of about 10% and a radiochemical purity of more than 95%. In vitro experiments revealed that the modified affibody retained the specific affinity to HER2. PET imaging showed that SKOV-3 and JIMT-1 xenografts were clearly visualized with excellent contrast and low abdomen backgrounds. On the contrary, the signals of MCF-7 tumor were difficult to visualize. The ROI values ranged from16.54±2.69% ID/g for SKOV-3 to 8.42±1.20 %ID/g for JIMT-1 tumors at 1h postinjection respectively. Poor uptake was observed from MCF-7 tumors with 1.71±0.34% ID/g at the same time point. Besides, a significant linear correlation between % ID/g values and relative HER2 expression levels was also found. Conclusions:18FAl-NOTA-MAL-MZHER2:342 is a promising tracer for in vivo detecting HER2 status with the advantages of facile synthesis and favorable pharmacokinetics. It may be useful in differential diagnosis, molecularly targeted therapy and prognosis of the cancers.

Escape of U251 glioma cells from temozolomide-induced senescence was modulated by CDK1/survivin signaling.

Temozolomide (TMZ) has been widely used in conjunction with radiotherapy for treating various types of cancers. However, tumor cells arrested in senescence due to TMZ administration can sometimes escape and become drug resistant. In the current study, the possible role of survivin in the senescence escape of TMZ-treated glioma cells was comprehensively studied. The levels of survivin and CDK1 expression in a human glioma cell line (U251) were monitored, and cell apoptosis, cell cycle distribution, anchorage-independent growth, and senescence were studied in U251 cells in different degrees of senescence. To further investigate how survivin affects the TMZ-resistance of gliomas, we modulated the levels of survivin and CKD1 expression in TMZ-treated cells and then examined how the treated cells responded. The results showed that knockdown of the survivin gene increased the sensitivity of glioma cells to TMZ treatment by inducing senescent cells to become apoptotic. Moreover, after senescence was induced, expression of the survivin gene became suppressed, but survivin levels returned to normal after the cells had escaped from senescence. While down-regulation of the survivin gene in senescent and senescence-escaping U251 cells had no effect on cell apoptosis, cell cycle distribution, or senescence status, it dramatically reduced the anchorage-independent growth ability of the cells. Additionally, CDK1 was able to not only enhance the anchorage-independent growth ability of the cells, but also contribute to their further senescence escape by modulating the survivin and other pathways. In conclusion, the survivin gene was necessary for glioma cells to escape from and enter into senescence during treatment with TMZ.