Abstract: To investigate the correlation between galectin3 and lymphatic metastasis and pleural metastasis in adenocarcinoma of the lung. MethodsImmunohistochemistry was used to determine expression of galectin3 in 63 primary lung adenocarcinomas specimens and 34 adenocarcinomas metastatic of pleural specimens. ResultsThe patterns of galectin3 expression were cytoplasmic and nuclear. All cases of nuclear galectin3 also showed a cytoplasmic immunoreactivity. In primary tumors the positive galectin3 expression was found in 92.1% of the cytoplasm and 31.7% of the nucleus. Only the nuclear location of galectin3 was associated with lymphatic metastasis　(P=0.03)　and clinical stages(TNM stages)(P＜0.05)． In pleural secondary adenocarcinomas the positive expression rate of galectin3 in the cytoplasm and nucleus was 97.1% and 85.3% respectively, and the nuclear staining was significantly higher than the primary tumour(P＜0.05). ConclusionNuclear expression of galectin 3 can enhance the invasive and metastatic potential of lung adenocarcinomas and can be used as a biological marker of lymph node and/or pleural metastasis.

Key words: Betagalactosidase, Carcinoma,nonsmall cell lung, Neoplasm metastasis