Abstract
The aim of the present study was to prove that a mouse model closely simulates human oral cancer progression by comparing the expression levels of transforming growth factor (TGF)-β1, E-cadherin, N-cadherin, tumor protein (TP)53, RB1 inducible coiled-coil (RB1CC)1 and hypoxia inducible factor (HIF)-1α at different stages of oral squamous cell carcinoma (OSCC) in humans and mice. The expression levels of TGF-β1, E-cadherin, N-cadherin, TP53, RB1CC1, and HIF-1α were detected by immunohistochemical staining in normal oral mucosa, oral mucosa dysplasia, OSCC primary tumor and carcinoma tissues from lymph node metastases. Tissue samples were obtained from human specimens and the Balb/c mouse model of lymphatic metastases oral carcinoma, induced by 4-nitroquinoline-1-oxide in drinking water. The results indicated no significant differences in the expression levels of TGF-β1, E-cadherin, N-cadherin, TP53, RB1CC1 and HIF-1α between humans and mice, at any stage of OSCC examined (P>0.05). The expression of TGF-β1, N-cadherin, TP53 and RB1CC1 increased in different stages of OSCC in both humans and mice. The expression of E-cadherin decreased from normal oral mucosa to OSCC, and increased in lymph node metastases in both human and mouse samples. The expression of HIF-1α increased from normal oral mucosa to OSCC, and decreased in lymph node metastases in both human and mouse samples. Additionally, the expression of p53 was positively correlated with that of RB1CC1 in human and mouse samples (r=0.971, P=0.029; r=0.97, P=0.03). Overall, the similar expression of multiple molecules in both human and mouse carcinoma prove that the mouse model of lymphatic metastases from oral carcinoma established in the present study may closely mimic human oral cancer.