RESUMO
<p><b>OBJECTIVE</b>To study the expression of targeting protein for Xklp2 (TPX2) and its significance in squamous cell carcinoma (SCC) of the lung.</p><p><b>METHOD</b>Two SCC cell lines and 4 immortalized bronchial epithelial cell lines (as a precancerous model) were examined by Western blot for TPX2 expression. Reverse transcription-polymerase chain reaction analysis for TPX2 was also performed using tumor tissues from 21 patients with SCC of the lung. The expression of TPX2 was studied by immunohistochemistry (using tissue microarray) on paraffin-embedded sections of pulmonary SCC and corresponding precancerous lesions from a group of 319 patients.</p><p><b>RESULTS</b>TPX2 was variably expressed in all the cell lines studied. Compared with matched controls using normal lung tissue, high level of TPX2 mRNA was detected in 16 of the 21 SCC tumor tissue samples analyzed. Immunohistochemical study showed that TPX2 was mainly present in tumor tissues but not in normal controls. The expression of TPX2 correlated with tumor grade, stage and nodal status. As for precancerous lesions, the level of TPX2 was also increased, in accordance with the degree of dysplasia.</p><p><b>CONCLUSIONS</b>Expression of TPX2 may play a role in carcinogenesis of bronchial epithelium and tumor progression of pulmonary SCC. It may also represent a potential biomarker for surveillance of SCC of lung.</p>