SF2523 inhibits human chondrosarcoma cell growth in vitro and in vivo.

Developing novel therapeutic agents against chondrosarcoma is important. SF2523 is a PI3K-Akt-mTOR and bromodomain-containing protein 4 (BRD4) dual inhibitor. Its activity in human chondrosarcoma cells is tested. Our results show that SF2523 potently inhibited survival, proliferation and migration, and induced apoptosis activation in SW1353 cells and primary human chondrosarcoma cells. The dual inhibitor was yet non-cytotoxic to the primary human osteoblasts and OB-6 osteoblastic cells. SF2523 blocked Akt-mTOR activation and downregulated BRD4-regulated genes (Bcl-2 and c-Myc) in chondrosarcoma cells. It was more efficient in killing chondrosarcoma cells than other established PI3K-Akt-mTOR and BRD4 inhibitors, including JQ1, perifosine and OSI-027. In vivo, intraperitoneal injection of SF2523 (30 mg/kg) potently inhibited subcutaneous SW1353 xenograft tumor growth in severe combined immunodeficient mice. Akt-mTOR inhibition as well as Bcl-2 and c-Myc downregulation were detected in SF2523-treated SW1353 tumor tissues. In conclusion, targeting PI3K-Akt-mTOR and BRD4 by SF2523 potently inhibited chondrosarcoma cell growth in vitro and in vivo.

[Biological characteristics of human umbilical cord-derived mesenchymal stem cells and their differentiation into chondrogenic and osteogenic cells].

OBJECTIVE: To investigate the isolation and expansion of mesenchymal stem cells (MSCS) from human umbilical cord Wharton's jelly and their biological identities, and explore the possibility of inducing human umbilical cord-derived MSCS to differentiate into chondrogenic and osteogenic cells. METHODS: The hUCMSCs were isolated form human umbilical cord by tissue adherence and digested with collagenase NB4, dispase II and hyaluronidase. The morphology, proliferation and immunophenotype of the 3rd passage cells were analyzed, and then the chondrogenic and osteogenic differentiation was tested and evaluated by specific staining methods.cells were induced to chondrogenic and osteogenic differentiation in vitro. RESULTS: The isolation of hUCMSCs by digestion with collagenase NB4, dispase II and hyaluronidase was efficient. After seeded for 24 hours, the adherent cells showed spindle shape and fibroblast cell-like shape and the size of hUCMSCs was homogeneous. Flow cytometry analysis revealed that the hUCMSCs were positive for CD44, CD105, CD90, CD73, but were negative for CD45, CD34, CD14, CD19 and HLA-DR. These cells could be induced to differentiate into chondrogenic and osteogenic cells under proper inducing conditions. The hUCMSCs retained the appearance and phenotype even after being expanded more than 40 passages in vitro. CONCLUSIONS: The human MSCs could be isolated from human umbilical cord Wharton's jelly, and it was easy to propagate these MSCs. An in vitro method for isolation and purification of hUCMSCs from human umbilical cord has been established. The cultured cells were composed of only undifferentiated cells and their biological properties were stable. The hUCMSCs are expected to be a new type of stem cells of tissue engineering.