Nuclear and cytoplasmic Maspin expression in primary non-small cell lung cancer.

Aim: To investigate whether nuclear and cytoplasmic Maspin expression is associated with distinct clinicopathological parameters and TP53 expression in a representative series of primary non-small cell lung cancer (NSCLC).

Methods: Tissue microarrays (n=487) were used to immunohistochemically analyse expression of Maspin and TP53. Cytoplasmic and nuclear expression of Maspin was scored on the basis of the percentage of positive tumour cells. Univariate analysis of clinicopathological variables potentially affecting tumour-specific survival was performed.

Results: Immunohistochemical Maspin expression (nuclear and cytoplasmic) was informative in 72.3% (352/487) of cases. Cytoplasmic and nuclear Maspin immunoreactivity in >or=10% of tumour cells was detected in 37.8% (133/352) and 65.3% (230/352) of informative cases, respectively. Nuclear and cytoplasmic Maspin staining was observed more frequently in primary squamous cell carcinomas than in other lung cancer types. Only nuclear Maspin immunoreactivity was significantly associated with positive TP53 staining. Cytoplasmic or nuclear Maspin expression was not associated with tumour-specific survival.

Conclusion: Maspin expression was found both in the nucleus and the cytoplasm of NSCLC, more frequently in squamous cell carcinomas. However, no association with tumour-specific survival could be demonstrated.