Addition of oligosaccharide decreases the freezing lesions on human red blood cell membrane in the presence of dextran and glucose

Although incubation with glucose before freezing can increase the recovery of human red blood cells frozen with polymer, this method can also result in membrane lesions. This study will evaluate whether addition of oligosaccharide (trehalose, sucrose, maltose, or raffinose) can improve the quality of red blood cell membrane after freezing in the presence of glucose and dextran. Following incubation with glucose or the combinations of glucose and oligosaccharides for 3 h in a 37 °C water bath, red blood cells were frozen in liquid nitrogen for 24 h using 40% dextran (W/V) as the extracellular protective solution. The postthaw quality was assessed by percent hemolysis, osmotic fragility, mean corpuscle volume (MCV), distribution of phosphatidylserine, the postthaw 4 °C stability, and the integrity of membrane. The results indicated the loading efficiency of glucose or oligosaccharide was dependent on their concentrations. Moreover, addition of trehalose or sucrose could efficiently decrease osmotic fragility of red blood cells caused by incubation with glucose before freezing. The percentage of damaged cell following incubation with glucose was 38.04 ± 21.68% and significantly more than that of the unfrozen cells (0.95 ± 0.28%, P < 0.01). However, with the increase of the concentrations of trehalose, the percentages of damaged cells were decreased steadily. When the concentration of trehalose was 400 mM, the percentage of damaged cells was 1.97 ± 0.73% and similar to that of the unfrozen cells (P > 0.05). Moreover, similar to trehalose, raffinose can also efficiently prevent the osmotic injury caused by incubation with glucose. The microscopy results also indicated addition of trehalose could efficiently decrease the formation of ghosts caused by incubation with glucose. In addition, the gradient hemolysis study showed addition of oligosaccharide could significantly decrease the osmotic fragility of red blood cells caused by incubation with glucose. After freezing and thawing, when both glucose and trehalose, sucrose, or maltose were on the both sides of membrane, with increase of the concentrations of sugar, the percent hemolysis of frozen red blood cells was firstly decreased and then increased. When the total concentration of sugars was 400 mM, the percent hemolysis was significantly less than that of cells frozen in the presence of dextran and in the absence of glucose and various oligosaccharides (P < 0.01). However, when both glucose and trehalose were only on the outer side of membrane, with increase of the concentrations of sugars, the percent hemolysis was increased steadily. Furthermore, addition of oligosaccharides can efficiently decrease the osmotic fragility and exposure of phosphatidylserine of red blood cells frozen with glucose and dextran. In addition, trehalose or raffinose can also efficiently mitigate the malignant effect of glucose on the postthaw 4 °C stability of red blood cells frozen in the presence of dextran. Finally, addition of trehalose can efficiently protect the integrity of red blood cell membrane following freezing with dextran and glucose. In conclusion, addition of oligosaccharide can efficiently reduce lesions of freezing on red blood cell membrane in the presence of glucose and dextran.     

5′-nucleotidase activity in permanent human lymphoid cell lines Implication for cell proliferation and aging in vitro

5′-Nucleotidase of 11 human lymphoid cell lines was measured. These cell ines were homogeneous B, T and Null cells, had an unlimited lifespan in vitro, and were subcultivated from leukemic cells of patients with Burkitt lymphoma, the blastic phase of chronic myelocytic leukemia, or acute lymphoblastic leukemia. 5′-Nucleotidase activities in normal human lymphocytes and in human fibroblasts (VA-13 and IMR-90) could be determined at a cellular protein concentration as low as 0.025 and 0.007 mg/ml, respectively. In all the eleven lymphoid cell lines, including 8 B-cell lines (RPMI 8422, B46M, RPMI 1788, DAUDI, HRIK, B411-4, B85 and DND-3-9A), 2 T-cell lines (MOLT 3 and RPMI 8402) and 1 Null cell line (NALM-1) 5′-nucleotidase was undetectable with the protein concentration range from 0.033 to 8.543 mg/ml. Previously 5′-nucleotidase activity was found to increase 10-, 6- and 20-fold in normal human embryonic lung (WI-38 and IMR-90 cells) and chick embryo fibroblasts, respectively, from a young rapidly proliferative to a senescent non-proliferative stage (Sun, A.S., Aggarwal, B.B. and Packer, L. (1975) Arch. Biochem. Biophys. 170, 1 and Sun, A.S., Alvarez, L.J. Reinach, P.S. and Rubin, E. (1979) Lab. Invest. 41, 1). These data demonstrate that the large increase in 5′-nucleotidase activity occurs concomitantly with the in vitro senescence of these normal cell lines. The present study suggests that this large increase in 5′-nucleotidase activity during cell aging is absent in these permanently lymphoid cell lines. The undetectable 5′-nucleotidase activity may be a biochemical characteristic of these homogeneous B, T and Null cells originating from the aforesaid leukemias. The implications of these results for cell proliferation and aging are discussed.     

FOXL2-induced follistatin attenuates activin A-stimulated cell proliferation in human granulosa cell tumors

Human granulosa cell tumors (GCTs) are rare, and their etiology remains largely unknown. Recently, the FOXL2 402C > G (C134W) mutation was found to be specifically expressed in human adult-type GCTs; however, its function in the development of human GCTs is not fully understood. Activins are members of the transforming growth factor-beta superfamily, which has been shown to stimulate normal granulosa cell proliferation; however, little is known regarding the function of activins in human GCTs. In this study, we examined the effect of activin A on cell proliferation in the human GCT-derived cell line KGN. We show that activin A treatment stimulates KGN cell proliferation. Treatment with the activin type I receptor inhibitor SB431542 blocks activin A-stimulated cell proliferation. In addition, our results show that cyclin D2 is induced by treatment with activin A and is involved in activin A-stimulated cell proliferation. Moreover, the activation of Smad signaling is required for activin A-induced cyclin D2 expression. Finally, we show that the overexpression of the wild-type FOXL2 but not the C134W mutant FOXL2 induced follistatin production. Treatment with exogenous follistatin blocks activin A-stimulated cell proliferation, and the overexpression of wild-type FOXL2 attenuates activin A-stimulated cell proliferation. These results suggest that FOXL2 may act as a tumor suppressor in human adult-type GCTs by inducing follistatin expression, which subsequently inhibits activin-stimulated cell proliferation.     

Dutasteride affects progesterone metabolizing enzyme activity/expression in human breast cell lines resulting in suppression of cell proliferation and detachment

Recent evidence indicates that progesterone metabolites play important roles in regulating breast cancer. Previous studies have shown that breast carcinoma and tumorigenic breast cell lines have higher 5alpha-reductase and lower 3alpha-hydroxysteroid oxidoreductase (3alpha-HSO) and 20alpha-HSO activities and mRNA expression levels than normal tissue and non-tumorigenic cell lines. The 5alpha-reduced progesterone metabolites such as 5alpha-dihydroprogesterone (5alphaP) promote both mitogenic and metastatic activity in breast cell lines in culture, whereas the 4-pregnene metabolites, 4-pregnen-3alpha-ol-20-one (3alphaHP) and 4-pregnen-20alpha-ol-3-one (20alphaHP) have the opposite (anti-cancer-like) effects. The 5alpha-reductase inhibitor dutasteride has been shown to inhibit 5alpha-reduction of testosterone to 5alpha-dihydrotestosterone in prostate tissue, resulting in decreased prostate volume. The aim of this study was to determine if dutasteride is an effective inhibitor of progesterone 5alpha-reduction in human breast cell lines and if such inhibition reduces mammary cell proliferation and detachment. The effect of dutasteride on progesterone metabolizing enzyme activities and mRNA expression were examined in tumorigenic MCF-7 and non-tumorigenic MCF-10A human breast cell lines. Dutasteride (10(-6)M) inhibited progesterone conversion to 5alpha-pregnanes by >95% and increased 4-pregnene production. The results indicated that effects of dutasteride on the progesterone metabolizing enzymes are due to direct inhibition of 5alpha-reductase activity and to altered levels of expression of 5alpha-reductase and HSO mRNAs. Treatment of cells with progesterone without medium change for 72 h resulted in significant conversion to 5alpha-pregnanes and increases in cell proliferation and detachment. The increases in proliferation and detachment were blocked by dutasteride and were reinstated by concomitant treatment with 5alphaP, providing proof-of-principle that the effects were due not to progesterone but to the 5alpha-reduced metabolites. This study provides the first evidence that dutasteride is a potent progesterone 5alpha-reductase inhibitor and that such inhibition may be beneficial in breast cancer.     

利用IVF废弃胚胎为核移植受体构建人体细胞克隆胚胎

目的：探讨利用IVF废弃胚胎构建人体细胞克隆胚胎的发育潜能及其在人治疗性克隆应用的可能性。方法：收集2008年7-12月在广州医学院第三附属医院进行体外受精-胚胎移植周期中的多精受精胚胎和MII期体外受精失败卵母细胞,运用显微操作技术构建人体细胞克隆胚胎,观察胚胎发育情况。结果：多精受精胚胎为核移植受体的克隆胚胎能够发育到8-细胞期,受精失败MII期卵母细胞为核移植受体的克隆胚胎能够激活,但不能够卵裂。两种IVF废弃的胚胎构建的人体细胞克隆胚胎在去核成功率,注核成功率上无显著差异（P＆gt;0.05）,但卵裂率和8细胞率上具有显著差异（P＆lt;0.05）。结论：多精受精胚胎比MII期体外受精失败卵母细胞更适合作为人核移植受体细胞。     

Co-culture with human synovium-derived mesenchymal stem cells inhibits inflammatory activity and increases cell proliferation of sodium nitroprusside-stimulated chondrocytes

Rheumatoid arthritis (RA) and osteoarthritis (OA) are primarily chronic inflammatory diseases. Mesenchymal stem cells (MSCs) have the ability to differentiate into cells of the mesodermal lineage, and to regulate immunomodulatory activity. Specifically, MSCs have been shown to secrete insulin-like growth factor 1 (IGF-1). The purpose of the present study was to examine the inhibitory effects on inflammatory activity from a co-culture of human synovium-derived mesenchymal stem cells (hSDMSCs) and sodium nitroprusside (SNP)-stimulated chondrocytes. First, chondrocytes were treated with SNP to generate an in vitro model of RA or OA. Next, the co-culture of hSDMSCs with SNP-stimulated chondrocytes reduced inflammatory cytokine secretion, inhibited expression of inflammation activity-related genes, generated IGF-1 secretion, and increased the chondrocyte proliferation rate. To evaluate the effect of IGF-1 on inhibition of inflammation, chondrocytes pre-treated with IGF-1 were treated with SNP, and then the production of inflammatory cytokines was analyzed. Treatment with IGF-1 was shown to significantly reduce inflammatory cytokine secretion in SNP-stimulated chondrocytes. Our results suggest that hSDMSCs offer a new strategy to promote cell-based cartilage regeneration in RA or OA.     

Study of potent cytotoxic activity of Helleborus cyclophyllus Boiss against a human adenocarcinoma cell line

Helleborus cyclophyllus Boiss is a rhizomatous plant species, with strong allelochemical properties, that has been used since ancient times for its therapeutic properties. In the present study we investigated the ability of an aqueous-soluble fraction of the methanol extract of H. cyclophyllus Boiss leaves, to induce apoptotic cell death on A549 human bronchial epithelial adenocarcinoma cells. A primary human lung fibroblasts’ cell line was used as a model of normal-healthy cells for comparison. Cell morphology was examined after appropriate staining, cytotoxic activity of the extract was determined by the MTT assay, the type of cell death was analyzed by flow cytometry, confirmation of apoptosis was evaluated with the analysis of caspase-3, PARP1 by western blotting, while the chemical composition was assessed by liquid chromatography–tandem mass spectrometry (LC–MS/MS). H. cyclophyllus Boiss extract was selectively active on A549 cells inducing significant morphological changes, even at low concentrations. Characteristic morphological alterations included the release of vesicular formations from A549 cell membranes (ectosomes), detachment of cells from their substrate, generation of a large vesicle into the cytoplasm (thanatosome) and the formation of apoptotic bodies. The selective apoptotic action on treated cells was also confirmed by biochemical criteria. Low concentrations, however, did not affect normal cells. The phytochemical analysis of the extract revealed the presence of cardiac glucosides, bufadienolides and phytoecdysteroids. To the best of our knowledge, the above-mentioned sequences of events leading selectively cancer cells to apoptosis, has not been reported before.Electronic supplementary materialThe online version of this article (10.1007/s10616-020-00425-4) contains supplementary material, which is available to authorized users.     

Anti-proliferative and differentiation-inducing activities of the green tea catechin epigallocatechin-3-gallate (EGCG) on the human eosinophilic leukemia EoL-1 cell line

A novel approach for the treatment of leukemia is the differentiation therapy in which immature leukemia cells are induced to attain a mature phenotype when exposed to differentiation inducers, either alone or in combinations with other chemotherapeutic or chemopreventive drugs. Over the past decade, numerous studies indicated that green tea catechins (GTC) could suppress the growth and induce apoptosis on a number of human cancer cell lines. However, the differentiation-inducing activity of GTC on human tumors remains poorly understood. In the present study, the effect of the major GTC epigallocatechin-3-gallate (EGCG) on the proliferation and differentiation of a human eosinophilc leukemic cell line, EoL-1, was examined. Our results showed that EGCG suppressed the proliferation of the EoL-1 cells in a dose-dependent manner, with an estimated IC(50) value of 31.5 microM. On the other hand, EGCG at a concentration of 40 microM could trigger the EoL-1 cells to undergo morphological differentiation into mature eosinophil-like cells. Using RT-PCR and flow cytometry, it was found that EGCG upregulated the gene and protein expression of two eosinophil-specific granule proteins, the major basic protein (MBP) and eosinophil peroxidase (EPO), in EoL-1 cells. Taken together, our findings suggest that EGCG can exhibit anti-leukemic activity on a human eosinophilic cell line EoL-1 by suppressing the proliferation and by inducing the differentiation of the leukemia cells.     

Enhanced casein kinase II activity in human tumour cell cultures

Casein kinase II (CKII) activity is enhanced as much as 2–3 fold in established and 4–5-fold in transformed human cell lines when compared to that of fibroblasts and primary human tumour cell cultures where CKII activity never exceeded a basic level. The high activity of CKII in transformed cells and in established cell lines was reduced to about the same basic level after treatment with heparin, a highly specific inhibitor of CKII activity. The activity of the cAMP-dependent protein kinase was virtually the same in fibroblasts and various human tumour cell lines investigated.     

Physical and functional interaction of human nuclear uracil-DNA glycosylase with proliferating cell nuclear antigen

Uracil residues arise in DNA by the misincorporation of dUMP in place of dTMP during DNA replication or by the deamination of cytosine in DNA. Uracil-DNA glycosylase initiates DNA base excision repair of uracil residues by catalyzing the hydrolysis of the N-glycosylic bond linking the uracil base to deoxyribose. In human cells, the nuclear form of uracil-DNA glycosylase (UNG2) contains a conserved PCNA-binding motif located at the N-terminus that has been implicated experimentally in binding PCNA. Here we use purified preparations of UNG2 and PCNA to demonstrate that UNG2 physically associates with PCNA. UNG2 co-eluted with PCNA during size exclusion chromatography and bound to a PCNA affinity column. Association of UNG2 with PCNA was abolished by the addition of 100 mM NaCl, and significantly decreased in the presence of 10 mM MgCl(2). The functional significance of the UNG2.PCNA association was demonstrated by UNG2 activity assays. Addition of PCNA (30-810 pmol) to standard uracil-DNA glycosylase reactions containing linear [uracil-(3)H]DNA stimulated UNG2 catalytic activity up to 2.6-fold. UNG2 activity was also stimulated by 7.5 mM MgCl(2). The stimulatory effect of PCNA was increased by the addition of MgCl(2); however, the dependence on PCNA concentration was the same, indicating that the effects of MgCl(2) and PCNA on UNG2 activity occurred by independent mechanisms. Loading of PCNA onto the DNA substrate was required for stimulation, as the activity of UNG2 on circular DNA substrates was not affected by the addition of PCNA. Addition of replication factor C and ATP to reactions containing 90 pmol of PCNA resulted in two-fold stimulation of UNG2 activity on circular DNA.     

NPAS2 regulates proliferation of acute myeloid leukemia cells via CDC25A-mediated cell cycle progression and apoptosis

Promoted proliferation and associated suppression of apoptosis at various stages of myeloid differentiation are well-known features of acute myeloid leukemia (AML), but understanding of the molecular processes involved remains limited. As a crucial circadian agent, neuronal PAS domain protein 2 (NPAS2) is widely recognized as a promising predictor of clinical outcome in various malignancies. Nevertheless, the understanding of its influence on AML is insufficient. Using KD cells and expression assays, we carried out detailed investigation of the role of NPAS2 in AML in vivo and in vitro. Firstly, we found that NPAS2 expression was elevated in AML cells both in vivo and in vitro. NPAS2 knockdown via lentiviral infection clearly suppressed proliferation of MV4-11 and MOLM-14 cells. Additionally, NPAS2 knockdown caused G1/S cell cycle arrest (CCA), which inhibited CDC25A expression. Moreover, NPAS2 knockdown promoted cell death, as evidenced by increased caspase-3 cleavage, and change in Bcl2/Bax production. Excessive CDC25A expression eliminated G1/S CCA triggered by NPAS2 knockdown and death of NPAS2 knocked down MOLM and MV4-11 cells. The expression of CDC25A was stabilized by NPAS2, which induced cell cycle progression and participated in suppression of cell death by modulating caspase-3 cleavage, and expression of Bcl2/Bax. We therefore indicated NPAS2 to be a crucial modulator of survival as well as proliferation. Our research sheds light on the etiology of the proliferation of promyelocytes modulated via NPAS2 with regard to AML.     

Calcium-activated nucleotidase 1 silencing inhibits proliferation,migration, and invasion in human clear cell renal cell carcinoma

Calcium-activated nucleotidase 1 (CANT1, belongs to the apyrase family, is widely expressed in various organs. However, the biological function of CANT1 remains poorly explored. In this study, we aimed to investigate the expression profile and functions of CANT1 in clear cell renal cell carcinoma (ccRCC). Our data show that the protein level of CANT1 was significantly higher in tumor tissues than in adjacent normal tissues. CANT1 silencing suppressed cell proliferation, migration, and invasion obviously in 769-P and 786-O cells, arrested cell cycle in S phase and promoted apoptosis in 769-P cells. In conclusion, the present study shows the different expression mode of CANT1 in human ccRCC tumor tissue and adjacent normal tissue, denotes the function of CANT1 in ccRCC cells and provides potential molecular mechanisms and pathways of CANT1 antitumor function in ccRCC.     

MicroRNA-5195-3p plays a suppressive role in cell proliferation,migration and invasion by targeting MYO6 in human non-small cell lung cancer

MiRNA-5195-3p (miR-5195-3p), a recently discovered and poorly studied miRNA, has been reported to suppress bladder cancer cell behavior. However, its regulatory role in non-small cell lung cancer (NSCLC) remains unclear. Here, the expression of miR-5195-3p was found to be reduced in NSCLC tissues and cells. The in vitro experiments showed that miR-5195-3p upregulation repressed cell proliferation, migration and invasion by CCK-8 and transwell assays. In addition, MYO6 was predicted and confirmed as a potential target of miR-5195-3p by Bioinformatics analysis, Luciferase reporter assay and western blot analysis. There was significantly negative correlation between miR-5195-3p and MYO6 in NSCLC tissues. Furthermore, MYO6 knockdown exhibited similar effects to those of miR-5195-3p overexpression in NSCLC cells, and restored MYO6 expression reversed the inhibitory effects of miR-5195-3p. Therefore, these results demonstrate that miR-5195-3p functions as a tumor suppressor by directly modulating MYO6 expression in NSCLC cells, and may be an innovative candidate target for NSCLC therapy.     

Oroxylin A induced apoptosis of human hepatocellular carcinoma cell line HepG2 was involved in its antitumor activity

We previously reported that wogonin, a flavonoid compound, was a potent apoptosis inducer of human hepatoma SMMC-7721 cells and murine sarcoma S180 cells. In the present study, the effect of oroxylin A, one wogonin structurally related flavonoid isolated from Scutellariae radix, on human hepatocellular carcinoma cell line HepG2 was examined and molecular mechanisms were also investigated. Oroxylin A inhibited HepG2 cell proliferation in a concentration- and time-dependent manner measured by MTT-assay. Treatment with an apoptosis-inducing concentration of oroxylin A caused typical morphological changes and apoptotic blebbing in HepG2 cells. DNA fragmentation assay was used to examine later apoptosis induced by oroxylin A. FACScan analysis revealed a dramatic increase in the number of apoptotic and G(2)/M phase arrest cells after oroxylin A treatment. The pro-apoptotic activity of oroxylin A was attributed to its ability to modulate the concerted expression of Bcl-2, Bax, and pro-caspase-3 proteins. The expression of Bcl-2 protein and pro-caspase-3 protein was dramatically decreased after treatment with oroxylin A. These results demonstrated that oroxylin A could effectively induce programmed cell death and suggested that it could be a promising antitumor drug.