MYCL GENOTYPES AND LOSS OF HETEROZYGOSITY IN NON-SMALL-CELL LUNG-CANCER

Some studies have suggested that the S allele of the MYCL oncogene, wh ich results from an intragenic EcoRI restriction fragment length polym orphism (RFLP), may be associated with cancer susceptibility. In addit ion, this allele has also been linked to metastases and adverse surviv al in certain cancers, although studies of lung cancer patients from d ifferent populations have yielded controversial results. We studied 10 8 cases of surgical resected non-small-cell lung cancer (NSCLC) and fo und no evidence that MYCL gentotypes were associated with tumour progr ession or a worse prognosis. However, the presence of loss of heterozy gosity (LOH) at this chromosome lp32 locus correlated significantly wi th regional lymph node involvement, as well as advanced TNM stage. The se data indicate the existence of a chromosome Ip candidate tumour-sup pressor gene(s), possibly in linkage disequilibrium with the EcoRI RFL P in specific populations, which appears to play a role in determining tumour progression in NSCLC. Refined mapping of the critical region o f loss should help attempts to identify and clone the candidate gene.