Differential oncogene and TNF-alpha mRNA expression in bone marrow cells from systemic lupus erythematosus patients

The aim of the study was to investigate the bone marrow expression of genes involved in cell growth and apoptosis in patients with systemic lupus erythematosus (SLE). Spontaneous expression of bcl-2, bax, c-myc. c-fos, c-jun, p53, Fas and tumour necrosis factor (TNF)-alpha by bone marrow cells was measured using either semiquantitative or quantitative reverse transcription polymerase chain reaction in SLE patients (n = 8) and in eight normal control subjects. The expression of bcl-2 was found to be higher in SLE patients than in controls. Bone marrow cells from SLE patients showed significant down-regulation of bax, c-myc, c-fos and p53 (P < or = 0.05), as compared to normal controls. In both SLE patients and controls the expression of c-jun and Fas was very low or undetectable. Finally, TNF-alpha gene expression was higher in bone marrow samples from SLE patients than in those of controls (P= 0.01). The abnormal expression of genes regulating cell growth and apoptosis in bone marrow cells from SLE patients may help explain the presence of autoreactive cells in secondary lymphoid organs and peripheral blood of SLE patients.