RT Journal Article SR Electronic T1 Inhibition of Differentiation by Transforming Growth Factor ß1 in Rhabdomyosarcoma Cells JF Chinese Journal of Clinical Oncology JO Cancer Biol Med FD China Anti-Cancer Association SP 327 OP 332 DO 10.1007/s11805-007-0327-x VO 4 IS 5 A1 Shouli Wang A1 Huihua Yao A1 Zhenghong Qin A1 Shigang Li A1 Yizhong Feng A1 Xiuzhen Wang A1 Min Deng A1 Lingling Guo A1 Lifeng Zhang YR 2007 UL http://www.cancerbiomed.org/content/4/5/327.abstract AB OBJECTIVE To study the effect of transforming growth factor ß1 (TGF-β1) on differentiation of rhabdomyosarcoma (RMS) cellsMETHODS RD (human embryonal RMS cell line) cells, cultured in differentiation medium containing 9-cis retinoic acid (9CRA), were treated with TGF-ß1. Proliferation of the cells was examined by the MTT assay. The differentiation specific proteins (sarcomeric actin and MyHC) and myogenic transcription factors (MyoD1 and myogenin) in the RD cells were assessed by immunofluorescence staining.RESULTS Compared to control cells, treatment with lower concentrations of TGF-ß1 (0.1 and 0.2 ng/ml) induced an increase in OD values after 4 d (P<0.01), whereas higher concentrations of TGF-ß1 (2 and 5 ng/ml) led to a reduction of cell viability (P<0.01). After exposure to 9CRA, the viability of the cells decreased significantly (P<0.01), while sarcomeric actin, MyHC and myogenin were induced. These changes were antagonized by TGF-β1 (0.1 ng/ml). No changes were observed in expression of MyoD1.CONCLUSION The RMS cells, derived from myogenic progenitors are committed to a myogenic fate, but are arrested in the differentiation course by the addition of TGF-ß1 which represses some of the myogenic transcription factors.