hUC-MSCs promote proliferation and migration of osteosarcoma cells by secreting IL-6 / 中国病理生理杂志

AIM: To investigate the effects of human umbilical cord-derived mesenchymal stem cells ( hUC-MSCs) on the proliferation and migration of osteosarcoma cells ( Saos-2 ) and the underlying molecular mechanism. METHODS:hUC-MSCs were isolated and cultured by tissue explants adherent method.The cell surface markers on hUC-MSCs were identified by flow cytometry.The effects of conditioned medium ( CM) from hUC-MSCs ( hUC-MSCs-CM) , re-combinant human interleukin-6 (rhIL-6) and IL-6 neutralizing antibody on the proliferation of Saos-2 cells were detected by CCK-8 assay and cell counting.IL-6 secretion of hUC-MSCs was assayed by ELISA.RT-PCR was used to assess the tran-scription level of proliferation-related genes proliferating cell nuclear antigen ( PCNA) , cyclin D1 and survivin.The migra-tion potential of hUC-MSCs and Saos-2 cells was measured by Transwell assay.RESULTS:hUC-MSCs migrated to Saos-2 cells.hUC-MSCs-CM contained a high concentration of IL-6, up to (1 835.5 ±134.1) ng/L.hUC-MSCs-CM and rhIL-6 promoted the proliferation and migration of Saos-2 cells.Addition of neutralizing antibody against IL-6 in the hUC-MSCs-CM impaired this proliferation and migration of Saos-2 cells.The mRNA expression of PCNA, cyclin D1 and survivin was up-regulated by hUC-MSCs-CM and rhIL-6, while this effect was dramatically attenuated by treatment with IL-6 neutralizing antibody.CONCLUSION:hUC-MSCs migrate to osteosarcoma cells and promote the proliferation and migration of osteo-sarcoma cells through secreting IL-6 in vitro.

Proliferation, senescence and differentiation of mesenchymal stem cells:canonical and non-canonical regulations of Wnt signaling pathway / 中国组织工程研究

BACKGROUND:As mesenchymal stem cells are commonly used as seed cells in studies of regenerative medicine and tissue engineering, the regulatory mechanism of their biological characteristics is a current research focus. OBJECTIVE:To summarize the regulations of Wnt signaling pathway on proliferation, senescence and differentiation of mesenchymal stem cells. METHODS:PubMed database and CNKI database were retrieved by computer using the key words of“mesenchymal stem cells, Wnt signaling pathway, proliferation, senescence, differentiation”in Chinese and English, respectively, between 2002 and 2014. Final y, 44 articles were included in result analysis. RESULTS AND CONCLUSION:Wnt signaling pathway is widely involved in the regulations of the biological characteristics of mesenchymal stem cells. Canonical Wnt signaling pathway reveals a bi-directional regulation effect on cellproliferation and osteogenic differentiation, and enhances senescence and neural differentiation, but inhibits adipogenic differentiation;non-canonical Wnt signaling pathway enhances senescence and osteogenic differentiation, and inhibits proliferation and adipogenic differentiation of mesenchymal stem cells, but it takes no part in neural differentiation of mesenchymal stem cells. So the regulations of Wnt signaling pathway on the biological characteristics of mesenchymal stem cells can be used as the new therapeutic targets of bone tissue engineering, nerve injury repair, and so on.

Effect of quercetin combined with cisplatin on proliferation and apoptosis of human osteosarcoma cell line MG-63 / 中国药理学通报

Aim To investigate the effect and mecha-nism of quercetin combined with cisplatin on prolifera-tion and apoptosis of human osteosarcoma cell line MG-63 . Methods MG-63 cells were treated with quercetin alone or combined with cisplatin. Cellular morphologic changes were observed under inverted phase contrast microscope. The effects of proliferation inhibition were assayed by CCK-8 method. The combination effect was judged through Chou-Talaly analysis. The apoptosis ra-tios of cells were analyzed by flow cytometry. The gene expression of Bcl-2 and caspase-3 was detected by RT-PCR assay. The protein expression of Bcl-2 and caspase-3 was measured by Western blot assay. Re-sults Quercetin alone or combined with cisplatin could inhibit the proliferation, but induce the apoptosis of MG-63 cells. Combination of quercetin and cisplatin revealed a synergistic effect on cell proliferation and apoptosis as it reduced the expression of Bcl-2 but en-hanced that of caspase-3 at both gene and protein lev-els. Conclusion Synergistic effect of quercetin com-bined with cisplatin on cell proliferation and apoptosis of MG-63 cells is possibly due to reduction of Bcl-2 and enhancement of caspase-3 expression.