Peroxisome proliferator-activated receptor gamma, a possible culprit in mycosis fungoides: an immunohistochemical study

Abstract

Background: It still remains debatable whether peroxisome proliferator-activated receptor gamma (PPARγ) is pro- or antineoplastic, and its exact role in mycosis fungoides (MF) remains unclear.

Objective: This prospective comparative study aimed to investigate the expression of PPARγ in MF and compare it with psoriatics and controls in a trial to deduce its possible role in MF. Also, we tried to clarify the relation between PPARγ and Bcl-2 in MF.

Methods: Twenty MF patients, 20 psoriatic patients and 20 controls were included. All participants underwent a skin biopsy, and immunohistochemical staining for both PPARγ and Bcl-2 were performed. Western blot analysis was performed for detection of both PPARγ and Bcl-2.

Results: The mean area per cent of PPARγ measured in the MF patients (57.1217±9.502417) was significantly higher (P<0.001) when compared with that of both the psoriatics (2.989±1.723) and controls (35.9357±8.1789). The mean area per cent of Bcl-2 in MF patients (9.3763±6.6328) was significantly higher (P<0.001) than that of both the psoriatics (2.35±1.35) and the controls (0.73105±0.5302)]. Our results were confirmed using the western blot analysis. We detected a highly significant positive correlation between the PPARγ and Bcl-2 mean area per cents in all patients. In our MF patients, both parameters were also positively correlated with the age of the patient, duration and stage of MF (P<0.05).

Conclusion: Our data suggest a possible role for PPARγ in the pathogenesis of MF possibly through several mechanisms, one of which might be conferring upon the lymphoma cells, a survival advantage at least partially through up regulating Bcl-2.