Epithelium maintains homeostasis by the signaling balance of growth stimulation and inhibition. Recently, loss of growth inhibitory effects of transforming growth factor-β(TGF-β) on epithelial cells is regarded as a possible mechanism of cancer. Although the genomic mutation in type I and type Ⅱ receptors of TGF-β is considered one of important mechanism of these inactivation, there might be another inactivation mechanism because the mutation rate is relatively low and inhibitory effect is not associated with the mutation. The purpose of this study is evaluating controlling mechanism type Ⅱ receptor of TGF-β by detecting effects of TGF-β on growth inhibition and on expression of cell cycle regulatory protein p21CIP1. Eight cancer cell lines derived from oral squamous cell carcinoma(OSCC) were examined. There was no growth inhibition effects by TGF-β except YD-8 cells. YD-8 cells which showed growth inhibition expresses p21CIP1 by TGF-β whether refractory cell lines, YD-9, did not. All of the tumor cells express mRNA of type Ⅱ receptor by RT-PCR and northern blot analysis, especially on YD-8 and YD-17M. From these results, most of oral cancer cell lines might loose the growth inhibitory effects by TGF-β, and the growth inhibition on YD-8 cells was mediated by expression of p21CIP1.

I. 서 론
 II. 연구 재료 및 방법
  가. 연구 재료
  나. Growth inhibition assay
  다. TGF-β1 수용체 mRNA 추출과 RT-PCR
  라. TGF-β1 수용체 Northern blotting
  마. Cell cycle regulatory protein Western blotting
 III. 연구 결과
  가. TGF-β1에 의한 세포성장 억제 효과
  나. TGF-β1 수용체의 mRNA 발현
  다. cell cycle regulatory protein 발현
 IV. 총괄 및 고찰
 V. 결 론
 VI. 참 고 문 헌

• 이근형(연세대학교 치과대학 구강병리학 교실, 구강종양연구소) | Geun Hyung Lee
• 배경진(연세대학교 치과대학 구강병리학 교실, 구강종양연구소)
• 최정희(연세대학교 치과대학 구강병리학 교실, 구강종양연구소) | Jung Hee Choi
• 김은정(연세대학교 치과대학 구강병리학 교실, 구강종양연구소) | Eun Jung Kim
• 이은주(연세대학교 치과대학 구강병리학 교실, 구강종양연구소) | Eun Ju Lee
• 김진(연세대학교 치과대학 구강병리학 교실, 구강종양연구소) | Jin Kim correspondence