Apolipoprotein E polymorphism and central nervous system tumors: correlation with cell proliferation indices and clinical outcome

Aims: This study was designed to determine whether the polymorphism of apol ipoprotein E (apoE), one of the key regulatory proteins in cholesterol meta bolism, is related to varying susceptibility to central nervous sytem (CNS) neoplasms, and to evaluate any possible interaction between this polymorph ism and tumor cell proliferation or clinical outcome. Methods and results: 53 CNS tumors were selected. Follow-up and survival data were available for 36 patients. ApoE genotypes and cell proliferation indices (nucleolar orga nizer regions, MIB-1, PCNA, p53) were determined from paraffin-embedded tis sue by standard methods. Each of the indices of cell proliferation correlat ed positively with tumor grade and negatively with duration of clinical fol low-up and survival. There was a nonsignificant trend for apoE epsilon 2 al lele carriers to have high-grade tumors and apoE epsilon 4 allele carriers to have low-grade tumors. Possession of apoE epsilon 4 was associated with a more advanced age of disease presentation (p < 0.01) and a longer duratio n of follow-up (p < 0.04). No significant correlations were found between p ossession of either apoE epsilon 2 or apoE epsilon 4 alleles and indices of cell proliferation. Conclusions. These preliminary findings suggest that p ossession of apoE epsilon 4 allele may correspond to a more favorable clini cal course in terms of more advanced age of disease presentation, and longe r duration of follow-up and survival in patients with CNS neoplasms.