Biomarkers with relevance to survival in SS colon aGVHD. (A) Members of USP17L gene family are overexpressed in immune cells of patients with aGVHD with NRM within 6 months. (B) Quartile-based assessment of combined USP17L (USP17L3, USP17L7, USP17L11, USP17L12, USP17L15, and USP17L17) RNA, used to define “high expressors” as those cases with mean pooled USP17L transcripts in fourth quartile (Q4) showed significant difference with the other quartiles (pooled as “low expressors”) (unpaired t-test, ∗∗∗∗P < .0001). Kaplan-Meier curve comparing combined USP17L high vs low expressors for (C) NRM (log-rank P = .0012) and (D) overall survival (log-rank P = .0114) showed better survival in low expressors. (E) RNA-ISH staining for USP17L family on the cases shows significant stronger staining in the USP17L RNA transcript high expressor cohort (unpaired t-test, ∗P = .0156). (F) USP17L isoform RNA-ISH staining validation on paraffin-embedded archival tissue in a low (left panel) and a high (right panel) expressor case (×17 magnification with scale bar = 100 μm). Inset of low expressor panel shows staining of USP17L RNA (brown-black granules) predominantly in glandular epithelium (left edge) and minimally on immune cells. Inset of high expressor panel shows comparatively stronger staining of immune population (left half) as well as in the epithelium (inset magnification ×60 with scale bar = 50 μm). OS, overall survival.