Prognostic value of FOXP3 and TGF-β expression in both peripheral blood and lymph nodes in patients with B-Non Hodgkin’s lymphoma

Abstract

Foxp3 has been studied as a biomarker of Treg cells in many solid malignant diseases, although its role as an immunomodulator in B-NHL remain poorly understood and the effect of traditional chemotherapy on its expression remains unclear. In this study the role of circulating and intra-tumoral Treg and TGF-β in patients with B-NHL before and after chemotherapy was evaluated. Enumeration of Treg cells was carried out by flow cytometric staining of their cell surface markers CD4 and CD25 as well as by molecular analysis of its signature transcription factor FoxP3. Expression of FoxP3 was done using quantitative real-time PCR while TGF-β mRNA expression was semi-quantitatively assayed by the conventional reverse transcription-PCR. In addition, spontaneous versus mitogen-induced release of TGF-β by PBMCs was assessed by a short term cell culture followed by ELISA. This was done before and after six cycles of CHOP chemotherapy. The results were evaluated in relation to the clinicopathological data. A significant increase in mRNA transcripts of both Fox P3 and TGF-β as well as the percentage of CD4+/CD25+ in B-NHL patients before receiving the chemotherapy were recorded, when compared either to healthy controls or to patients after completion the treatment regimen. Interestingly 6 cycles of CHOP treatment caused significant reduction in all parameters under study, relative to the situation before treatment. A significant enhancement in spontaneous TGF-β release in B-NHL patient either before or after chemotherapy was obtained. These results strongly confirm the possible involvement of Treg cells and TGF-β in orienting the clinical course of the disease as well as the ability of targeting them in immunotherapeutic approaches.

Keywords

• FOXP3
• TGF
• Non Hodgkin’s lymphoma
• NHL