New flavonoids from the aerial part of Bupleurum chinense DC.

Four new flavonoids (1-4) and fourteen known compounds (5-18), were isolated from the aerial part of Bupleurum chinense DC. The structural determination of the new flavonoids was accomplished using comprehensive spectroscopic methods, including 1D and 2D NMR spectra with references to the literatures, as well as high-resolution mass spectrometric analysis. The anti-proliferative activities of the flavonoids (1-18) against HeLa cells were evaluated using the MTT assay with cisplatin as the positive control.

A New Alkaloid from the Aerial Parts of Bupleurum chinense DC.

A new isoalloxazine alkaloid, named bupleurine A (1), along with five known compounds (2-6), were isolated from the aerial parts of Bupleurum chinense DC. The structure elucidation of the new alkaloid (1) was employed by combining NMR and HR-MS data with comparison of reference in the literature. Five known compounds (2-6) were isolated from Bupleurum genus for the first time. Additionally, their antiproliferative activities on HeLa cells were evaluated by MTT assay and IC50 of compounds 1 and 4-6 were below 10 µm after treatment for 24 h.

Expression of Nestin, CD133 and Sox2 in Meningiomas.

AIM: To investigate the expression of cancer stem cell markers in meningiomas. MATERIAL AND METHODS: CD133, Nestin and Sox2 expression levels in 35 paraffin-embedded meningioma tissue samples were assessed using immunohistochemistry. RESULTS: In this study, five cases were atypical (WHO Grade II), two were anaplastic (WHO Grade III), and 28 were benign (WHO Grade I). Among atypical and anaplastic meningiomas, all were positive for Nestin and CD133, and 4 were positive for Sox2. Of the 28 benign meningiomas, 23 were positive for Nestin, 11 were positive for CD133, and none were positive for Sox2. In addition, Nestin and CD133 were expressed at significantly higher levels in the non-benign group than in the benign group. CONCLUSION: Nestin, CD133 and Sox2 expression levels may be correlated with the WHO pathological grade. Specifically, more aggressive meningiomas are characterized by higher positivity rates and higher levels of Nestin, CD133 and Sox2 expression in positive cells.

[Experimental study of dendritic cells transfected with cancer stem like cells RNA against 9L brain tumors].

OBJECTIVE: To investigate the anti-tumor efficacy of dendritic cells (DC) vaccination transfected with total RNA of cancer stem like cells and to discuss the mechanism of immune response, so as to provide experimental basis for clinical application. METHODS: Dendritic cells were isolated from F344 bone marrow cells, then these dendritic cells were transfected with total RNA of 9L cancer stem cells or 9L monolayer cells. F344 rats bearing with 9L brain tumors were treated by subcutaneous injection of either PBS, unpulsed DC, DC transfected with 9L monolayer cells RNA (DC-9LTS) or DC transfected with 9L tumor spheres RNA (DC-9L)3, 10, 17. And 21 days after tumor implantation, the brains and sera were obtained from the different groups, the lymphocytes infiltration was detected by immunohistochemistry, and the concentration of interferon-γ (IFN-γ) was tested by ELISA. The survival time was observed and determined using the method of Kaplan Meier analysis. RESULTS: The rats vaccinated with DC transfected with 9L tumor spheres RNA (DC-9LTS) and the monolayer cell RNA (DC-9L) expired with median survival time of 36 and 31 days, respectively. The animals bearing intracranial 9L gliosarcoma were vaccinated with un-pulsed DC vaccine, all expired with a median survival time of 21 days. The Kaplan-Meier survival curve showed that the rats treated with DC-9LTS had longer survival than the other groups (P<0.01). There was significant difference among DC-9L group, DC group, and PBS group (P<0.01). There was no significant difference between DC group and PBS group (χ2=0.071, P=0.789).The concentration of IFN-gamma of DC-9LTS group [(157.08±7.25) ng/L] was much higher than those of the other groups (P<0.05). DC-9LTS could effectively enhance T-cell infiltration, a large number of CD8+ cells were detected in and around the tumor in DC-9LTS group, compared with DC-9L group, DC and PBS group (P<0.001). The expression of CD8+ cell was not detected in DC group and PBS group. However no expression of CD4+ cells was observed in all the groups. CONCLUSION: Immunotherapy using DC transfected with 9L CSLCs total RNA was more effective for the treatment of 9L brain gliomas, and the strategy prolonged the survival of 9L glioma-bearing rats significantly, which provides a scientific foundation for further investigation of this approach to eradicate gliomas.

Comparison of the neural differentiation potential of human mesenchymal stem cells from amniotic fluid and adult bone marrow.

Human mesenchymal stem cells (MSCs) are considered a promising tool for cell-based therapies of nervous system diseases. Bone marrow (BM) has been the traditional source of MSCs (BM-MSCs). However, there are some limitations for their clinical use, such as the decline in cell number and differentiation potential with age. Recently, amniotic fluid (AF)-derived MSCs (AF-MSCs) have been shown to express embryonic and adult stem cell markers, and can differentiate into cells of all three germ layers. In this study, we isolated AF-MSCs from second-trimester AF by limiting dilution and compared their proliferative capacity, multipotency, neural differentiation ability, and secretion of neurotrophins to those of BM-MSCs. AF-MSCs showed a higher proliferative capacity and more rapidly formed and expanded neurospheres compared to those of BM-MSCs. Both immunocytochemical and quantitative real-time PCR analyses demonstrated that AF-MSCs showed higher expression of neural stemness markers than those of BM-MSCs following neural stem cell (NSC) differentiation. Furthermore, the levels of brain-derived growth factor and nerve growth factor secreted by AF-MSCs in the culture medium were higher than those of BM-MSCs. In addition, AF-MSCs maintained a normal karyotype in long-term cultures after NSC differentiation and were not tumorigenic in vivo. Our findings suggest that AF-MSCs are a promising and safe alternative to BM-MSCs for therapy of nervous system diseases.

An experimental study of dendritic cells transfected with cancer stem-like cells RNA against 9L brain tumors.

Cancer stem cells are defined as a subpopulation of cancer cells with the capacity to self-renew and differentiate, which may play critical roles in tumor initiation, progress and resistance to current treatments. It has been reported that Dendritic cells (DCs) transfected with total tumor RNA could induce strong antitumor T-cell responses both in vivo and in vitro. In the study, we investigated the characteristics of 9L tumor spheres, and evaluated the antitumor effects of DCs transfected with 9L tumor spheres RNA in vivo. The results showed that 9L tumor spheres have the properties of cancer stem cells, and the majority of 9L cells were positive for CD133 and nestin. DCs transfected with 9L tumor spheres RNA can significantly inhibit glioma growth and prolong the survival of 9L glioma-bearing rats. These results demonstrated that 9L cancer stem like cells were enriched in tumor spheres, and they were a part of CD133+ cells, DCs transfected with cancer stem cells RNA may be an effective therapy for glioma.