Peripheral myeloid-derived suppressor and T regulatory PD-1 positive cells predict response to neoadjuvant short-course radiotherapy in rectal cancer patients.

摘要: // Maria Napolitano 1 , Crescenzo D’Alterio Eleonora Cardone 2 Anna Trotta Biagio Pecori 3 Daniela Rega Ugo Pace Dario Scala Giosue Scognamiglio 4 Fabiana Tatangelo Carmela Cacciapuoti 5 Roberto Pacelli 6 Paolo Delrio Stefania Immunology Unit, Istituto Nazionale per lo Studio e la Cura dei Tumori “Fondazione Giovanni Pascale” – I.R.C.C.S.-Naples, Italy Colorectal Surgery, Radiotherapy, Pathology, Trasfusional Service, Department of Advanced Biomedical Sciences, Federico II University School Medicine, and di Biostrutture Bioimmagini C.N.R., Naples, Correspondence to: Scala, e-mail: scalaste@gmail.it ; s.scala@istitutotumori.na.it Keywords: MDSC, Treg, radiotherapy, rectal cancer Received: November 03, 2014      Accepted: December 31, Published: January 21, 2015 ABSTRACT Short-course preoperative radiotherapy (SC-RT) followed by total mesorectal excision (TME) is one therapeutic option for locally advanced (LARC) patients. Since radio-induced DNA damage may affect tumor immunogenicity, Myeloid-derived suppressor cells (MDSCs) T regulatory (Tregs) were evaluated in 13 patients undergoing SC-RT TME LARC. Peripheral Granulocytic-MDSCs (G-MDSC) [LIN − /HLA-DR /CD11b + /CD14 /CD15 /CD33 ], Monocytic (M-MDSC) [CD14 −/low CD11b ] Tregs [CD4 /CD25 hi+ /FOXP3 - CTLA-4/PD1] basal value was significantly higher LARC compared to healthy donors (HD). MDSC at time 0 (T0), after weeks (T2-T5) from radiotherapy; before surgery (T8) 6–12 months (T9, T10). G-MDSC decreased T5 further T8 while M-MDSC T5; reached the lowest T5. poor responder displayed a major decrease an increase Treg-PD-1. In this pilot study MDSCs during treatment could represent biomarker response Further studies are needed confirm that deepest reduction Treg-PD1 within 5–8 beginning discriminate responding SC-RT.