OBJECTIVETo study the regulation and effect of the expression of nm23-H1 gene in different processes of regional lymph node metastases of oral squamous cell carcinomas(OSCC).

METHODSBy immunohistochemical analysis in 200 paraffin-embedded tissues of OSCC and Western Blot in 9 fresh tissues of OSCC using a monoclonal antibody, the expression of nm23-H1/NDPK-A were detected in dividing groups accompanied with the clinical and pathological data of cervical lymph node metastases and modes of invasion.

RESULTSThe rates of negative expression of nm23-H1/NDPK-A had significant differences between metastatic cases(34/81) and non-metastatic cases(15/119). The nm23-H1/NDPK-A negative group showed higher frequency of lymph node metasteses (P < 0.01). In the different metastatic processes, There were significantly differential expressions of nm23-H1/NDPK-A among stage N0, N1 and N2(P < 0.01), distinct involved quantities of lymph nodes (P < 0.01), dissimilar metastatic involved levels(P < 0.05), definite modes of invasion(P < 0.01) and different cell differentiations(P < 0.01). There were much higher negative expressions in those cases of N1 stage(23/38), only one lymph node to be involved(23/39), metastasized to submandibular nodes or/and superior deep cervical nodes(17/28 and 12/29, respectively), IV c types of invasion(33/54) and poor differentiations(9/19).

CONCLUSIONThe results indicated that nm23-H1/NDPK-A played an more important role in switching the initial metastases formation than in influencing the later metastases spread because the negative expressions of nm23-H1/NDPK-A in solid tumors of OSCC would induce the formation of high metastatic cellular subpopulations. It was also confirmed that nm23-H1 gene might be a metastatic suppressor and may be useful in predicting the initial lymph node metastases in OSCC.