Expression of peroxisome proliferator-activated receptorsb/d in mycosis fungoides

There is considerable controversy on whether peroxisome proliferator-activated receptor (PPAR) b/d stimulates or inhibits apoptosis and cell proliferation. Dysregulated apoptosis of skin-homing memory T cells is involved in the pathogenesis and therapeutic implications of mycosis fungoides (MF), the most common and indolent form of cutaneous T-cell lymphoma. Objective To detect PPAR b/d expression in patients with MF and compare it with that in normal healthy controls, in an attempt to define its role in MF pathogenesis. Patients and methods Semiquantitative evaluation of PPAR b/d mRNA using the reverse transcriptase-PCR technique was performed on patients diagnosed with early MF (stages Ia, Ib, and IIa) (n = 20) and in controls (n = 24). Results Patients with MF showed significantly higher levels of PPAR b/d than did controls (Po0.001), and these levels correlated significantly with the extent of lesions (P = 0.008) but not with patient age or disease duration (P= 0.23 and 0.80, respectively). Conclusion Our results point to a possible role of PPAR b/d in the pathogenesis of MF and a significant influence on disease severity. Further studies using more accurate quantitative techniques are anticipated to support the present findings and clarify the functional role of this key substance.