Diagnosis of Cutaneous Acute Graft‑Versus‑Host Disease Through Circulating Plasma miR‐638, miR‐6511b‐5p, miR‐3613‐5p, miR‐455‐3p, miR‐5787, and miR‐548a‐3p as Prospective Noninvasive Biomarkers Following Allogeneic Hematopoietic Stem Cell Transplantation

Background There are currently no laboratory tests that can accurately predict the likelihood of developing acute graft‐versus‐host disease (aGVHD), a patient's response to treatment, or their survival chance. This research aimed to establish circulating miRNAs as diagnostic, prognostic, or predictive biomarkers of aGVHD. Methods In a prospective cohort, we studied the incidence of cutaneous aGVHD in AML patients undergoing allo‐HSCT at Shariati Hospital in Tehran, Iran during 2020–2023. Patients with cutaneous aGVHD were labeled as the case group, while patients without cutaneous aGVHD were selected as the control group. Accordingly, the expression levels of six significant miRNAs (miR‐638, miR‐6511b‐5p, miR‐3613‐5p, miR‐455‐3p, miR‐5787, miR‐548a‐3p) were evaluated by quantitative reverse transcription–polymerase chain reaction (RTqPCR) in three different time‐points: before transplantation, on day 14 and day 21 after transplantation. Results The levels of plasma miR‐455‐3p, miR‐5787, miR‐638, and miR‐3613‐5p were significantly downregulated, while miR‐548a‐3p, and miR‐6511b‐5p were significantly upregulated in individuals with cutaneous aGVHD in comparison to patients without GVHD. Additionally, the possibility for great diagnostic accuracy for cutaneous aGVHD was revealed by ROC curve analysis of differentially expressed miRNAs (DEMs). Conclusion The study findings encourage us to hypothesize that the aforementioned miRNAs may contribute to the predominance of aGVHD, particularly low‐grade cutaneous aGVHD.