Expression And Potential Roles Of Neuropilin-1 And Its Ligand Semaphorin 3A In Tongue Squamous Cell Carcinoma

ObjectiveTo investigate the expression of NRP-1 and its ligand SEMA 3A in the human tongue squamous cell carcinoma tissues and cell line SCC9. The effect of exogenous SEMA 3A protein on SCC9 was observed.Methods(1) Immunohistochemical staining was used to survey the expression of NRP-1 and SEMA 3A between human carcinoma of tongue specimens and non- malignant tongue tissues, and follow-up the survival rate. The data were analyzed with SPSS 17.0 software package.(2) Immunocytochemistry was used to survey the expression of NRP-1, SEMA 3A in cell line SCC9.(3) Western blot and reverse transcription polymerase chain reaction(RT-PCR) were used to survey the expression of NRP-1, SEMA 3A in human carcinoma of tongue specimens, cell line SCC9 and non-malignant tongue tissues.(4) MTT assay was used to study the effect of exogenous SEMA 3A on the proliferation of SCC9.(5) Transwell assay was used to investigate the effect of exogenous SEMA 3A on the migration and invasion of SCC9.Results(1) Immunohistochemical staining showed SEMA 3A was strongly positive in 8/42 human carcinoma of tongue specimens and positive in 16/42 human carcinoma of tongue specimens while negative in 18/42 human carcinoma of tongue specimens; SEMA 3A was strongly positive in 8/15 non-maligna -nt tongue tissues and positive in 5/15 non-malignant tongue tissues while negative in 2/15 non-malignant tongue tissues. NRP-1 was strongly positive in 13/42 human carcinoma of tongue specimens and positive in 24/42 human carcinoma of tongue specimens while negative in 5/42 human carcinoma of tongue specimens; NRP-1 was positive in 3/15 non-malignant tongue tissues. There was significant difference between human carcinoma of tongue specimens and non-malignant tongue tissues (P<0.05); The expression of SEMA 3A and NRP-1 has no correlations with the clinical factors including age, gender, histological differentiation, lymphatic metastasis and clinical stage(P>0.05); The overall survival rates of 1,3 years were respectively 76.2% and 57.1% in the whole group,in SEMA 3A positive groups they were respectively 83.3%, 62.5% and in SEMA 3A negative groups they were 66.7%, 50.0%, there was no significant difference in survival rates between the two groups,and in SEMA 3A strongly positive groups they were respectively 87.5%(7/8),higher than negative group but no significant difference; in NRP-1 positive group they were respectively 75.7%, 54.0% and in negative group they were 80.0%, 80.0%, there was also no significant difference between the two groups. There was relation between age and 1-year survival rate. Whether or not lymph node metastases has something to do with 3-year survival rate.(2) Immunocytochemistry showed the expression of SEMA 3A was negative in cell line SCC9 and the expression of NRP-1 was positive in cell line SCC9.(3) Western bloting and RT-PCR indicated the negative expression of SEMA 3A and positive expression of NRP-1 in the human tongue squamous carcinoma tissues and cell line SCC9.(4) The proliferation of SCC9 was inhibited by 1000pM exogenous SEMA 3A (P<0.05).(5) There was no significant difference between the migration and invasion of SCC9 exposed to 1000pM exogenous SEMA 3A and control (P>0.05).Conclusion(1) The negative expression of SEMA 3A and enhanced expression of NRP-1 in human carcinoma of tongue specimens and cell line SCC9 indicated that the progression of tumor may have something to do with their abnormal expression. (2) Exogenous SEMA 3A could inhibite the proliferation of SCC9 indicated that it may provide a new way for tumor gene-targeted therapy.