RESUMO
<p><b>OBJECTIVE</b>To study the expression of hTERT mRNA and Mad1 protein in lung cancer of Gejiu and Xuanwei and normal lung tissue and to investigate their correlations with lung cancer.</p><p><b>METHODS</b>Mad1 protein was detected by immunohistochemistry S-P method, and hTERT message RNA (mRNA) was detected by in situ hybridization (ISH) in 40 specimens of lung cancer of Gejiu Tin miners and 20 specimens of lung cancer of Xuanwei peasants and 20 specimens of normal lung tissue. The positive signals were quantitatively analyzed by HPIAS-100.</p><p><b>RESULTS</b>The positive unit (PU) of Mad1 protein was 16.77 +/- 6.01 in Gejiu Tin Miners lung cancer group, and 19.36 +/- 4.54 in Xuanwei peasant lung cancer group, compared with the normal lung tissue (46.05 +/- 7.26). The difference was highly significant (P < 0.01); The PU of hTERT mRNA was 72.10 +/- 13.07 in Gejiu Tin miners lung cancer group, and 74.20 +/- 15.17 in Xuanwei peasant lung cancer group, which was higher than that in normal tissue group (10.70 +/- 2.21). The difference was significant (P < 0.01). The expression of Mad1 protein was negatively correlated with the expression hTERT mRNA (P < 0.05, r = 0.9881, r = -0.999).</p><p><b>CONCLUSION</b>Reduced hTERT mRNA expression may play an important role in the occurrence of lung cancer. The expression of hTERT mRNA and deletion of Mad1 protein are closely related to pathogenesis of lung cancer.</p>