1. Department of Medical Biology, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria
2. Research Institute at Medical University of Plovdiv (RIMU), 4000 Plovdiv, Bulgaria
3. Department of Hematology and Medical Oncology, Clinic of Internal Medicine II, Jena University Hospital, 07743 Jena, Germany
4. Institute of Molecular Cell Biology, Jena University Hospital, 07745 Jena, Germany
5. School of Medicine, Faculty of Health Sciences and Wellbeing, University of Sunderland, Sunderland SR1 3SD, UK