[Interferon-α mediating the functional damage of CD56dimCD57+natural killer cells in peripheral blood of systemic lupus erythematosuss].

OBJECTIVE: To investigate the regulatory effect of interferon-α (IFN-α) on the apoptosis and killing function of CD56dimCD57+ natural killer (NK) cells in systemic lupus erythematosus (SLE) patients, and to explore the specific mechanism. METHODS: A total of sixty-four newly treated SLE patients and sixteen healthy controls (HC) enrolled in the Second Hospital of Dalian Medical University were selected as the research subjects. And the gene expression levels of molecules related to NK cell-killing function were detected by real-time quantitative polymerase chain reaction. CD56dimCD57+ NK cells were co-cultured with the K562 cells, and the apoptotic K562 cells were labeled with Annexin-Ⅴ and 7-amino-actinomycin D. Peripheral blood mononuclear cells were treated with 20, 40, and 80 µmol/L hydrogen peroxide (H2O2), and treated without H2O2 as control, the expression level of perforin (PRF) was detected by flow cytometry. The concentration of IFN-α in serum was determined by enzyme linked immunosorbent assay. The expression levels of IFN-α receptors (IFNAR) on the surface of CD56dimCD57+ NK cells were detected by flow cytometry, and were represented by mean fluorescence intensity (MFI). CD56dimCD57+ NK cells were treated with 1 000 U/mL IFN-α for 24, 48 and 72 h, and no IFN-α treatment was used as the control, the apoptosis and the expression levels of mitochondrial reactive oxygen species (mtROS) were measured by flow cytometry and represented by MFI. RESULTS: Compared with HC(n=3), the expression levels of PRF1 gene in peripheral blood NK cells of the SLE patients (n=3) were decreased (1.24±0.41 vs. 0.57±0.12, P=0.05). Compared with HC(n=5), the ability of peripheral blood CD56dimCD57+ NK cells in the SLE patients (n=5) to kill K562 cells was significantly decreased (58.61%±10.60% vs. 36.74%±6.27%, P < 0.01). Compared with the control (n=5, 97.51%±1.67%), different concentrations of H2O2 treatment significantly down-regulated the PRF expression levels of CD56dimCD57+ NK cells in a dose-dependent manner, the 20 µmol/L H2O2 PRF was 83.23%±8.48% (n=5, P < 0.05), the 40 µmol/L H2O2 PRF was 79.53%±8.56% (n=5, P < 0.01), the 80 µmol/L H2O2 PRF was 76.67%±7.16% (n=5, P < 0.01). Compared to HC (n=16), the serum IFN-α levels were significantly increased in the SLE patients (n=45) with moderate to high systemic lupus erythematosus disease activity index (SLEDAI≥10) [(55.07±50.36) ng/L vs. (328.2±276.3) ng/L, P < 0.001]. Meanwhile, compared with HC (n=6), IFNAR1 expression in peripheral blood CD56dimCD57+ NK cells of the SLE patients (n=6) were increased (MFI: 292.7±91.9 vs. 483.2±160.3, P < 0.05), and compared with HC (n=6), IFNAR2 expression in peripheral blood CD56dimCD57+ NK cells of the SLE patients (n=7) were increased (MFI: 643.5±113.7 vs. 919.0±246.9, P < 0.05). Compared with control (n=6), the stimulation of IFN-α (n=6) significantly promoted the apoptosis of CD56dimCD57+ NK cells (20.48%±7.01% vs. 37.82%±5.84%, P < 0.05). In addition, compared with the control (n=4, MFI: 1 049±174.5), stimulation of CD56dimCD57+ NK cells with IFN-α at different times significantly promoted the production of mtROS in a time-dependent manner, 48 h MFI was 3 437±1 472 (n=4, P < 0.05), 72 h MFI was 6 495±1 089 (n=4, P < 0.000 1), but there was no significant difference at 24 h of stimulation. CONCLUSION: High serum IFN-α level in SLE patients may induce apoptosis by promoting mtROS production and inhibit perforin expression, which can down-regulate CD56dimCD57+ NK killing function.

PKMYT1 as a Potential Target to Improve the Radiosensitivity of Lung Adenocarcinoma.

OBJECTIVE: This article is dedicated to finding important genes related to the prognosis of lung adenocarcinoma (LUAD), looking for a new gene that may affect tumor radiosensitivity, and conducting basic experiments to verify the relationship between this gene and the radiosensitivity of LUAD. METHODS: The gene expression profiles GSE32863, GSE33532, and GSE43458 were obtained from NCBI-GEO. GEO2R and a Venn diagram were used to identify upregulated genes. STRING and Cytoscape were applied to develop a protein-protein interaction network (PPI) and analyze the modules. The Database for Annotation, Visualization and Integrated Discovery (DAVID) was used to process the GO and KEGG pathway analysis. The Kaplan Meier plotter and Gene Expression Profiling Interactive Analysis (GEPIA) were applied to get the significant prognostic information and differential expression between LUAD tissues and normal lung tissues. Western blotting and Q-PCR were used to detect the expression of PKMYT1 in tissues. Small interfering RNAs (siRNAs) were used to knockdown PKMYT1. The colony survival experiment was used to assess the effect of PMYT1 on the radiosensitivity of tumor cells. Cell cycle analysis was used to assess cell cycle distribution. RESULTS: We identified 14 genes (PKMYT1, TTK, CHEK1, CDC20, PTTG1, MCM2, CDC25C, MCM4, CCNB1, CDC45, MAD2L1, CCNB2, BUB1, and CCNA2) that are important for LUAD and may be potential therapeutic targets. We confirmed that PKMYT1 is highly expressed in LUAD and firstly demonstrated that artificially silencing the expression of PKMYT1 can abrogate IR-induced G2/M phase arrest and increase the sensitivity of cancer cells to radiation. CONCLUSION: In summary, we obtained 14 core genes related to the poor prognosis of LUAD via bioinformatical analysis. We identified that PKMYT1 was significantly upregulated in LUAD tissues and firstly demonstrated that knockdown of PKMYT1 can eliminate the radiation-induced G2/M arrest, resulting in a lower survival rate for cells receiving radiation therapy. Our findings suggested that PKMYT1 is a promising target to improve the radiosensitivity of LUAD.

The Bidirectional Effects of Arsenic on miRNA-21: A Systematic Review and Meta-analysis.

OBJECTIVE: Arsenic is a metalloid environmental carcinogen involved in the occurrence and development of many cancers. miRNA-21 plays a crucial role in arsenic-induced carcinogenesis. We aimed to elucidate the mechanism by which miRNA-21 influences arsenic-induced cancer. METHODS: We used meta-analysis of published studies to determine how arsenic induces cancerous cells through miRNA-21. RESULTS: Low-dose arsenic exposure (⪕ 5 µmol/L) can increase miRNA-21 and phosphorylated signal transducter and activator of transcription 3 (pSTAT3) expression, and decrease programmed cell death protein 4 (PDCD4) and protein sprouty homolog 1 (Spry1) expression. High-dose arsenic exposure (> 5 µmol/L), can increase miRNA-21 expression, and decrease Spry1 and E-cadherin expression. Short-term arsenic exposure (⪕ 24 h) can increase miRNA-21 and pSTAT3 expression, and decrease PDCD4 expression. Moreover, long-term arsenic exposure (> 24 h) can increase the miRNA-21, STAT3, and pSTAT3 expression, and decrease PDCD4 expression. We found that activation of miRNA-21 and pSTAT3 were most pronounced following long-term arsenic exposure at low doses, and the effects on PDCD4 expression were most pronounced following short-term arsenic exposure at low doses. miRNA-21 inhibitors increased the expression of tumor suppressor genes PDCD4, PTEN, and Spry1 and miRNA-21-mimics suppressed the expression of these tumor suppressor genes. CONCLUSION: Arsenic can cause cancer by activating miRNA-21 and inhibiting the expression of PDCD4, PTEN, and Spry1.

[Effect of Catgut Implantation on Spatial Learning-memory Ability, Expression of Hippocampal Protein Kinase C Interacting Protein 1 and GluR 2 and Ca2+ Content in Rats with Chronic Ischemic Cognitive Impairment].

OBJECTIVE: To observe the effect of catgut embedment at "Baihui" (GV 20), "Dazhui" (GV 14), etc. on learning-memory ability, expression of hippocampal protein kinase C interacting protein 1 (PICK 1) and glutamate receptor 2 (GluR 2) proteins and level of calcium ions, so as to explore its mechanism underlying improvement of vascular cognitive impairment. METHODS: A total of 56 male SD rats were randomly divided into sham operation, model, catgut embedment and medication groups (n=14 in each). The chronic ischemic cognitive impairment model was established by permanent occlusion of bilate-ral common carotid arteries. The catgut embedment was applied to GV 20, GV 14, "Shenshu" (BL 23) and "Xuanzhong" (GB 39), once a week, for 4 weeks. Rats of the medication group received intraperitoneal injection of monosialate tetrahexose ganglioside sodium (GM-1, 0.33 mg/kg), once daily for 4 weeks. The rats' learning-memory ability was detected by Morris water maze tasks, pathological changes of hippocampal Nissl's bodies were tested by Nissl staining. The expression levels of PICK 1 and GluR 2 proteins in the hippocampus were detected by Western bolt (WB), and the concentration of calcium ions in the hippocampus tissue was measured by Bicinchoninic acid (BCA) assay. RESULTS: After modeling, the mean escape latencies of place navigation test were significantly increased while the crossing times of target platform quadrant of space probing test notably decreased in the model, catgut embedment and medication groups compared with their own individual pre-modeling (P<0.01). Following the treatment, the increased mean escape latencies and decreased crossing times were markedly reversed in both catgut embedment and medication groups relevant to the model group (P<0.01, P<0.05). Nissl staining showed that after mode-ling, a smaller amount of Nissl bodies with dispersing arrangement, reduction in cellular volume, and loss of large amount of cells with vague structure, and hyperchromatic nuclear pyknosis were found in the hippocampus tissue, which was relatively milder in both catgut embedment and medication groups. The hippocampal PICK 1 protein expression and the calcium ion concentration were obviously higher in the model group than in the sham operation group (P<0.01), and significantly lower in both embedment and medication groups than in the model group (P<0.01, P<0.05), while hippocampal GluR 2 protein expression was obviously lower in the model group than in the sham operation group (P<0.01), and markedly higher in both embedment and medication groups than in the model group (P<0.05, P<0.01). No significant differences were found between the embedment and medication groups in the abovementioned indexes (P>0.05). CONCLUSION: Catgut implantation at GV 20 etc. can effectively improve the learning-memory ability in rats with chronic ischemic cognitive impairment, which may be related to its effects in down-regulating the expression of PICK 1 and calcium ion concentration and up-regulating the expression of AMPA receptor subunit GluR 2 protein in the hippocampus.

Facile Synthesis of Cadmium-Free Zn-In-S:Ag/ZnS Nanocrystals for Bio-Imaging.

High quality cadmium-free Zn-In-S:Ag doped-nanocrystals (d-NCs) were synthesized via a simple one-step noninjection route using silver nitrate, indium acetate, zinc acetate, oleylamine, S powder and 1-dodecanethiol as starting materials in an organic phase. The size and optical properties can be effectively tailored by controlling the reaction time, reaction temperature, Ag(+) dopant concentration, and the molar ratio of In to Zn. The photoluminescence wavelength of as-prepared Zn-In-S:Ag NCs covered a broad visible range from 458 nm to 603 nm. After being passivated by protective ZnS shell, the photoluminescence quantum yield (PLQY) of Zn-In-S:Ag(+) /ZnS was greatly improved to 43.5%. More importantly, the initial high PLQY of the obtained core/shell d-NCs in organic media can be preserved when being transferred into the aqueous media via ligand exchange. Finally, high quality Zn-In-S:Ag(+) /ZnS d-NCs in aqueous phase were applied as bio-imaging agents for identifying living KB cells.