Comparative study on the stem cell phenotypes of C6 cells under different culture conditions / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Glioma stem cell (GSC) hypothesis posits that a subpopulation of cells within gliomas have true clonogenic and tumorigenic potential. Significantly, a more controversial correlate to GSC is that cells in different culture conditions might display distinct stem cell properties. Considering these possibilities, we applied an approach comparing stem cell characteristics of C6 glioma cells under different culture conditions.</p><p><b>METHODS</b>C6 cells were cultured under three different growth conditions, i.e., adherent growth in conventional 10% serum medium, non-adherent spheres growth in serum-free medium, as well as adherent growth on laminin-coated flask in serum-free medium. Growth characteristics were detected contrastively through neurosphere formation assay and cell cycle analysis. Markers were determined by immunofluorescence, relative-quantitative reverse transcription (RT)-PCR, Western blotting and flow cytometry. Side population cells were analyzed via flow cytometry. Tumor models were detected by magnetic resonance imaging and hematoxylin & eosin staining. Data analyses were performed with SPSS software (17.0).</p><p><b>RESULTS</b>C6 cells (C6-Adh, C6-SC-Sph and C6-SC-Adh) showed distinctive growth patterns and proliferation capacity. Compared to suspending C6-SC-Sph, adherent C6-Adh and C6-SC-Adh displayed higher growth ratio. C6-SC-Sph and C6-SC-Adh showed enhanced capability of neurosphere formation and self-renewal. High side population ratio was detected in C6-SC-Sph and C6-SC-Adh. CD133 was not detected in all three kinds of cells. Conversely, Nestin and β-III-tubulin were demonstrated positive, nonetheless with no statistical significance (P > 0.05). Interestingly, lower expression of glial fibrillary acidic protein was demonstrated in C6-SC-Sph and C6-SC-Adh. C6-Adh, C6-SC-Sph and C6-SC-Adh were all displayed in situ oncogenicity, while statistical difference of survival time was not confirmed.</p><p><b>CONCLUSIONS</b>C6 glioma cell line is endowed with some GSC phenotypes that can be moderately enriched in vitro when transferred into stem cell culture condition. The resultant tumor-spheres may be not a prerequisite or sound source of GSCs and adherent culture in stem cell medium is not a growth condition in favor of GSCs expanding in vivo.</p>

Angiogenesis inhibitory effect of saikosaponin-d on chicken embryo / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the inhibitory effects of saikosaponin-d (SSd) on angiogenesis in chicken embryos and its mechanism of action.</p><p><b>METHODS</b>Chorioallantoic membrane (CAM) model was established successfully in 86 chicken embryos. They were divided into 4 groups after fenestration: the three SSd treated groups (A, B and C) treated with high (20 microg/mL, n = 16), middle (10 microg/mL, n = 19) and low (5 microg/mL, n = 25) dose of SSd respectively, and the control group treated with 0.01 mol/L PBS (n = 26). The drug or reagent was administered by grafting 20 microL onto the surface of CAM. After incubation for 3 days, the vessel growth was recorded by digital photography; inflammatory cells were counted under light microscope with HE staining, and the positive rate of angiogenesis reaction was calculated by Leica image analyzer.</p><p><b>RESULTS</b>On the 6th day of the embryonic age, vessels in the chicken embryo CAM showed a radial growing in spok-wheel pattern around the gelatin sponges with lateral axis running through it. Whereas after 3 days of SSd treatment, the angiogenesis reduced significantly with vague microvessels around the sponge, and vascular truncation and absence revealed. Microscopic examinations showed that the number of microvessels and infiltrated inflammatory cells in the sponge and peripheral CAM mesenchyme in the SSd groups were less than those in the control group, especially on vessels of medium and small size (P < 0.05, P < 0.01, respectively), but was insignificant on great vessels (P > 0.05). Correlation analysis revealed no correlation between the number of the great vessels in CAM and the infiltrated inflammatory degrees (r = 0.117, P > 0.05), but the increase of small vessels in CAM was positively correlated with that of inflammatory cells (r = 0.971, P < 0.01).</p><p><b>CONCLUSIONS</b>SSd could inhibit the physiological angiogenesis of chicken embryoe, especially for the medium and small vessels, while there was no significant effect on great vessels (P > 0.05). Its mechanism of action may be related to its inhibition on leukocyte migration and activation.</p>

LRIG3 gene regulates biological activity of GL15 cell line / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effects of leucine-rich repeats and immunoglobulin-like domains 3 (LRIG3) on the biological activity of glioblastoma cell line GL15.</p><p><b>METHODS</b>Glioblastoma GL15 cells were cultured and transfected with LRIG3-EGFP plasmid. The location of LRIG3 in GL15 cells was observed with confocal microscopy. The proliferation and invasiveness of GL15 cells were detected with methyl thiazolyl tetrazolium (MTT) and Transwell methods respectively; the expression of epidermal growth factor receptor (EGFR) and LRIG3 mRNA and protein were detected with reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot respectively.</p><p><b>RESULT</b>After transfection with the plasmid LRIG-EGFP, LRIG3 fusion protein was found in cytoplasm of GL15 cells and cell proliferative and invasiveness were reduced. The expression of EGFR and LRIG3 varied with the duration of EGF treatment (100 ng/ml): the expression of EGFR decreased while the expression of LRIG3 increased as time prolonged.</p><p><b>CONCLUSION</b>LRIG3 can inhibit the proliferation and invasiveness of glioblastoma cells and may be used as a target gene in gene therapy of glioblastoma.</p>