[Functional significance of TGF-beta1 signal transduction pathway in oral squamous cell carcinoma].
OBJECTIVE
The aim of this study was to investigate the expression of transforming growth factor-beta1 (TGF-beta1) and its signaling pathway molecules in oral squamous cell carcinoma (OSCC) and analyze the association between these factors and genesis and metastasis of OSCC.


METHODS
The express of TGF-beta1, TbetaRI, TbetaRII and Smad4, a pivotal downstream molecule of its signaling, in 10 normal oral mucosa tissues and 108 OSCC was detected by SP immunohistochemistry, and thier correlation with genesis and metastasis of OSCC were assessed.


RESULTS
The expressions of TbetaRII and Smad4 were lower in the tumors (34.3%, 38.9%) than those in the normal oral epithelium (80.0%, 100.0%, P < 0.05). The positive expression rates of TGF-beta1 and TbetaRI in the normal oral epithelium and OSCC were not significantly different (P > 0.05). There was an inverse correlation between TGF-beta1, Smad4, TbetaRII, TbetaRI expression and clinical stages (P < 0.01). The expression of TGF-beta1 was related with histological differentiation and tumor localization (P < 0.05). There was a relationship beteween Smad4 expression and histological differentiation and lymph node metastasis (P < 0.05). The expression of TbetaRII in the samples with lymph node metastasis was less than that in the ones without lymph node metastasis (P < 0.01), although there was no association between expression of TbetaRII and lymph node metastasis status.


CONCLUSIONS
There is an important relationship between the abnormal TGF-beta1/Smad4 signal pathway and genesis and development of OSCC, while the low expressed Smad4 and TbetaRII may promote the metastasis of OSCC.
Wang
Xiu-mei
XM
Department of Stomatology, The Second Affiliated Hospital of Harbin Medical University, Harbin 150086, China. hrbwangmei@yahoo.com.cn
Liu
Cheng-min
CM
Zhang
Cheng-ren
CR
Xu
Xu-guang
XG
Fu
Song-bin
SB
D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D002462:Cell Membrane / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000378:metabolism* / Q000473:pathology; D009367:Neoplasm Staging; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D000077293:Receptor, Transforming Growth Factor-beta Type I; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism; D015398:Signal Transduction; D051901:Smad4 Protein / Q000378:metabolism; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*
D018125:Receptors, Transforming Growth Factor beta; C497796:SMAD4 protein, human; D051901:Smad4 Protein; D053773:Transforming Growth Factor beta1; D017346:Protein Serine-Threonine Kinases; D000077293:Receptor, Transforming Growth Factor-beta Type I; D000077294:Receptor, Transforming Growth Factor-beta Type II