Multidrug resistance related genes and p53 expression in human non small cell lung cancer.

BACKGROUND

Many genes (mdr1, mrp, DNA topoisomerases II) are known to be involved in the resistance to unrelated drugs (the MDR phenomenon), but the mechanisms of their activation have to be further investigated.

MATERIALS AND METHODS

Because several authors showed that p53 mutated gene was able to induce mdr1 overexpression, we evaluated in 51 non small cell lung cancer samples, already tested for p53 mutations, the expression of mdr1, mrp, DNA topoisomerase II alpha and beta mRNAs by qualitative RT-PCR assays.

RESULTS

Mutations of p53 were found in 56% of cases. Mdr1 expression was detected in 27%, mrp in 100%, topoisomerase alpha in 82% and beta in 94% of the samples.

CONCLUSIONS

It was not possible to detect any relationship between the expression of the MDR-related genes and tumor histological type, stage or lymph node involvement. Nevertheless, a close association between p53 alterations and either mdr1 gene (p = 0.001) or DNA topoisomerase II alpha (p = 0.003) expression was found.