Squamous cell carcinoma of the lung: does the nm23 gene expression correlate to the tumor stage?

We examined the nm23 gene activity in 30 human squamous cell carcinomas of the lung using the Northern blot analysis. Matched healthy lung tissue was available from 10 patients. 26 tumor samples were obtained after resection treatment between 1986 and 1990, 4 additional samples of advanced stages from autopsy. We found a significant increase of nm23 expression towards advanced stages of squamous cell carcinoma (IIIa vs. I: p < 0.015, IV vs. II: p < 0.043, IV vs. I: p < 0.043). Furthermore in stage I and II, poorly differentiated squamous cell carcinomas contained significantly more nm23 mRNA than did moderately differentiated ones (p < 0.027). We could also demonstrate an inverse correlation between the levels of nm23 mRNA and disease-free survival after resection treatment (p < 0.016, chi 2-test for trend). Thus the nm23-gene activity correlates to the tumor stage and the grade of differentiation of the squamous cell carcinoma of the lung, and is therefore of prognostic relevance. It might be possible to describe the biological behaviour of the individual tumor more accurately by the additional measurement of the nm23 mRNA.