The expression and function of PD-L1 in CD133(+) human liver cancer stem-like cells / 中华肿瘤杂志

Objective: To investigate the expression of programmed death protein-ligand 1 (PD-L1) in liver cancer stem-like cells (LCSLC) and its effect on the characteristics of tumor stem cells and tumor biological function, to explore the upstream signaling pathway regulating PD-L1 expression in LCSLC and the downstream molecular mechanism of PD-L1 regulating stem cell characteristics, also tumor biological functions. Methods: HepG2 was cultured by sphere-formating method to obtain LCSLC. The expressions of CD133 and other stemness markers were detected by flow cytometry, western blot and real-time quantitative polymerase chain reaction (RT-qPCR) were used to detect the expressions of stemness markers and PD-L1. The biological functions of the LCSLC were tested by cell function assays, to confirm that the LCSLC has the characteristics of tumor stem cells. LCSLC was treated with cell signaling pathway inhibitors to identify relevant upstream signaling pathways mediating PD-L1 expression changes. The expression of PD-L1 in LCSLC was down regulated by small interfering RNA (siRNA), the expression of stem cell markers, tumor biological functions of LCSLC, and the changes of cell signaling pathways were detected. Results: Compared with HepG2 cells, the expression rate of CD133 in LCSLC was upregulated [(92.78±6.91)% and (1.40±1.77)%, P<0.001], the expressions of CD133, Nanog, Oct4A and Snail in LCSLC were also higher than those in HepG2 cells (P<0.05), the number of sphere-formating cells increased on day 7 [(395.30±54.05) and (124.70±19.30), P=0.001], cell migration rate increased [(35.41±6.78)% and (10.89±4.34)%, P=0.006], the number of transmembrane cells increased [(75.77±10.85) and (20.00±7.94), P=0.002], the number of cloned cells increased [(120.00±29.51) and (62.67±16.77), P=0.043]. Cell cycle experiments showed that LCSLC had significantly more cells in the G(0)/G(1) phase than those in HepG2 [(54.89±3.27) and (32.36±1.50), P<0.001]. The tumor formation experiment of mice showed that the weight of transplanted tumor in LCSLC group was (1.32±0.17)g, the volume is (1 779.0±200.2) mm(3), were higher than those of HepG2 cell [(0.31±0.06)g and (645.6±154.9)mm(3), P<0.001]. The expression level of PD-L1 protein in LCSLC was 1.88±0.52 and mRNA expression level was 2.53±0.62, both of which were higher than those of HepG2 cells (P<0.05). The expression levels of phosphorylation signal transduction and transcription activation factor 3 (p-STAT3) and p-Akt in LCSLC were higher than those in HepG2 cells (P<0.05). After the expression of p-STAT3 and p-Akt was down-regulated by inhibitor treatment, the expression of PD-L1 was also down-regulated (P<0.05). In contrast, the expression level of phosphorylated extracellular signal-regulated protein kinase 1/2 (p-ERK1/2) in LCSLC was lower than that in HepG2 cells (P<0.01), there was no significant change in PD-L1 expression after down-regulated by inhibitor treatment (P>0.05). After the expression of PD-L1 was knockdown by siRNA, the expressions of CD133, Nanog, Oct4A and Snail in LCSLC were decreased compared with those of siRNA-negative control (NC) group (P<0.05). The number of sphere-formating cells decreased [(45.33±12.01) and (282.00±29.21), P<0.001], the cell migration rate was lower than that in siRNA-NC group [(20.86±2.74)% and (46.73±15.43)%, P=0.046], the number of transmembrane cells decreased [(39.67±1.53) and (102.70±11.59), P=0.001], the number of cloned cells decreased [(57.67±14.57) and (120.70±15.04), P=0.007], the number of cells in G(0)/G(1) phase decreased [(37.68±2.51) and (57.27±0.92), P<0.001], the number of cells in S phase was more than that in siRNA-NC group [(30.78±0.52) and (15.52±0.83), P<0.001]. Tumor formation in mice showed that the tumor weight of shRNA-PD-L1 group was (0.47±0.12)g, the volume is (761.3±221.4)mm(3), were lower than those of shRNA-NC group [(1.57±0.45)g and (1 829.0±218.3)mm(3), P<0.001]. Meanwhile, the expression levels of p-STAT3 and p-Akt in siRNA-PD-L1 group were decreased (P<0.05), while the expression levels of p-ERK1/2 and β-catenin did not change significantly (P>0.05). Conclusion: Elevated PD-L1 expression in CD133(+) LCSLC is crucial to maintain stemness and promotes the tumor biological function of LCSLC.

Lead compound optimization strategy (7) —— modification strategies for peptides / 药学学报

Most peptides have high binding affinity and good selectivity for endogenous receptors and are good lead compounds to develop into drugs. Many approved drugs are derived from the structural optimization of peptide molecules, such as the antihypertensive drug captopril and the anti-hepatitis C drug telaprevir. At present, the main problems in the development of peptide drugs include poor stability, short half-life, and high plasma clearance rate; lack of oral availability and poor patient compliance, a complex production process, and high production cost. Therefore, rational modification of peptides can not only reduce the production cost, but also improve the druggability of the peptides. Here we review structural modification strategies for peptides from the perspective of improving their physicochemical properties. These modification strategies are divided into two parts: one is modification of the peptide backbone, including unnatural amino acid modification, pseudopeptide strategy, inverse-peptide strategy, cyclization strategy, and terminal structure modification. Another is modification of the side chains of peptides, including fatty acid conjugation, polyethylene glycol conjugation, protein fusion strategy, and cholesterol conjugation.

Simultaneous Determination of Saponins in Dripping Pills Made from Astragali Radix and Panax notoginseng by UPLC-ELSD / 中草药·英文版

Objective To develop a simple and fast method for removing polyethylene glycol (PEG) and simultaneous determination of fives saponins, i.e. astragaloside IV, notoginsenoside R1, ginsenoside Rg1, ginsenoside Rb1, and ginsenoside Rd in dripping pills made from Astragali Radix and Panax notoginseng. Methods The extraction method was based on a liquid-liquid extraction using water-saturated n-butanol and the quantitative determination was based on ultra-performance liquid chromatography coupled with evaporative light scattering detection (UPLC-ELSD). The chromatographic analysis was performed on an Acquity UPLC HSS T3 column (100 mm × 2.1 mm, 1.8 µm) with a gradient elution of acetonitrile-0.1% formic acid aqueous solution within a runtime of 15 min. Results Compared to different methods, the proposed method could remove the interference of PEG in formulation. And the calibration curves showed good linearity during the test ranges. The method was validated for limits of detection and quantification, precision, and reproducibility. The recoveries were within the range of 96.87% – 99.97%. In addition, the verified method was firstly applied to determination of the five active ingredients in Qishen Yiqi Dripping Pills (QYDP) simultaneously. Conclusion The contents of five active ingredients are stable and homogeneous in QYDP, which indicates that the method could be readily utilized as a quality evaluation method for this traditional Chinese medicine dripping pills made from Astragali Radix and Panax notoginseng.

Effect of enteral nutrition via jejunostomy catheter on quality of life in gastric cancer patients who have undergone gastrectomy / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the effect of enteral nutrition via jejunostomy catheter on the quality of life in gastric cancer patients who have undergone gastrectomy.</p><p><b>METHODS</b>We retrospectively analyzed clinical data of 104 consecutive patients who had undergone curative resection for gastric cancer in Peking Union Medical College Hospital in 2011.All data were obtained from a prospectively maintained database of gastric cancer.The quality of life was compared between jejunostomy tube group(n=49)and tube-free group(n=55).</p><p><b>RESULTS</b>The two groups were matched in gender,age,tumor size,tumor location,histological type,pTNM stage,type of surgery,body mass index(BMI),quality of life scales,and cycles of postoperative adjuvant chemotherapy(all P>0.05).Also,the global health status(P=0.154),physical function score(P=0.321),role function score(P=0.492),and fatigue symptom score(P=0.845)were not significantly different between these two groups one month after surgery.Three and 6 months after the surgery,patients in the jejunostomy tube group had significantly higher overall health status scores( P<0.001,P=0.038),physical function scores(P=0.004,P=0.005),and role function scores(P=0.002,P=0.038)and significantly lower fatigue symptom scores(P=0.020,P=0.043)when compared to patients from tube-free group.</p><p><b>CONCLUSION</b>Enteral nutrition via jejunostomy catheter can improve the quality of life of gastric cancer patients who have undergone gastrectomy.</p>

Lymphoplasmapheresis for Guillain-Barre syndrome / 中南大学学报(医学版)

OBJECTIVE@#To evaluate the clinical therapeutic effect and security of lymphoplasmapheresis (LPE) for Guillain-Barre syndrome (GBS).@*METHODS@#Sixty-six GBS patients were randomly divided into 2 groups: the therapy group (33 patients) were treated with LPE in addition to the medical treatment; the control group (33 patients) only accepted the medical treatment. The therapeutic effect was evaluated with the initial recovery time of myodynamia and the myodynamia score difference, and the side effect of the therapy group was observed.@*RESULTS@#The therapy group were treated with LPE for 48 times,1.5 times per person. The average initial recovery time was quicker in the therapy group compared with that in the control group [(6.45+/-3.01) vs (8.36+/-3.83) days]. The difference of limb myodynamia score between pre-treatment and post-treatment in the therapy group was more than that in the control group. The improved number in the therapy group was more than that in the control group, but the ineffective number in the therapy group was not as many as that in the control group. The total effective rate in the therapy group was higher than that in the control group (51.5% vs 27.7%); the average hospital day in the therapy group was shorter than that in the control group [(19.42+/-7.25) vs (24.00+/-8.64) days]; and the difference had statistical significance(P0.05). After the second and the third LPE, the average myodynamia score continued to rise, and the difference had statistical significance (P<0.05). The incidence rate of side effects in the therapy group was 12.5%. Urticaria and hypotension were the major side effects, but they were light and could be relieved by symptomatic treatment.@*CONCLUSION@#The therapeutic effect of LPE is definite, and the side effect is scarce. LPE is safe and effective, and it is worth of generalization and applying in clinical practice.