Down-regulation of TGF-b1, TGF-b receptor 2, and TGF-b-associated microRNAs, miR-20a and miR-21, in skin lesions of sulfur mustard-exposed Iranian war veterans

Abstract

Sulfur mustard (SM) affects divergent cellular pathways including cell cycle, apoptosis, necrosis, and inflammatory responses. SM-induced lesions in skin include late-onset hyper-pigmentation, xerosis, and atrophy. It seems that TGF-b signaling pathway is a major player for SM pathogenesis. Here, we have employed a real-time polymerase chain reaction (PCR) approach to evaluate the expression alterations of all TGF-b variants and their receptors in skin biopsies obtained from 10 Iran–Iraq war veterans. Using specific LNA primers, the expression alteration of a TGF-bR2 regulator, miR-20a, and TGF-b downstream target, miR-21, was also assessed in the same samples Our real-time PCR data revealed a significant down-regulation of TGF-b1 and TGF-bR2, the major mediators of TGF-b signaling pathway, in skin biopsies of SM-exposed patients (p = 0.0015 and p = 0.0115, respectively). Down-regulation of TGF-b signaling pathway seems to contribute in severe inflammation observed in SM-exposed patients’ tissues. MiR-20a and miR-21, as two important TGF-b associated microRNAs (miRNAs), were also down-regulated in SM-exposed skin lesions, compared to those of control group (p = 0.0003). Based on our findings, these miRNAs could be directly or indirectly involve in the pathogenesis of SM. Altogether, our data suggest the suitability of TGF-b1, TGF-bR2, as well as miR-20a and miR-21 as potential biomarkers for diagnosis and treatment of SM-exposed patients.

• Gene expression
• miR-20a
• miR-21
• skin
• sulfur mustard
• TGF-b

Acknowledgements

We are grateful to Mr. Ali Mohammadian from Tehran University, Dr. Shahriar Khateri and Ms. Zohreh Ganjparvar from Janbazan Medical and Engineering Research Center for their valuable help and support.

Declaration of interest

This work was financially supported by a research grant from Janbazan Medical and Engineering Research Center (JMERC). The authors declare no conflicts of interests.