Fig. 4: Correlation between chromatin openness of circulating CD8⁺ T cells and treatment response to anti-PD-1 therapy (discovery cohort, n = 32).

a Patients with normalized area values above and below the threshold are indicated by filled (blue) and open circles, respectively, at each target peak. Sensitivity and specificity were calculated for a responder group (R, CR + PR) and a non-responder group (NR, PD + SD). MSI: microsatellite instability; MSS: microsatellite stability; EBV: Epstein–Barr virus. PD: progression disease; SD: stable disease; PR: partial response; CR: complete response. b Nine targets in descending order of accuracy (ACC) were statistically evaluated in combination. After normalized areas above and below the threshold had been converted to 1 and 0, respectively, these binary values were multiplied by values ranging from 1 (lowest) to 9 (highest) on the accuracy rank, to obtain a weighted score. Instead of normalized area values, the weighted scores were used for further ROC analysis and to calculate a threshold for each combination of the nine targets using Cutoff Finder. AUROC indicates the area under receiver operating characteristic. c Openness scores (weighted score) for a responder group (R, CR + PR) and a non-responder group (NR, PD + SD) with normalized area values were displayed in a dot plot (left graph). Bars and error bars indicate the mean area value and SEM for each group (n = 10 from R and n = 22 from NR). P-value < 0.0001 was obtained using the two-sided Mann–Whitney U test. Arb. units indicate arbitrary units. Waterfall plots according to the openness of circulating CD8⁺ T cells were displayed in the middle panel. Green: CR + PR; Orange: SD: Red: PD. d Threshold value of combination with the nine targets was used to determine clinical outcomes of anti-PD-1 therapy using progression-free survival (PFS) curve. Tumor progression scores for patients above (n = 12) and below (n = 20) the threshold are shown in blue and red, respectively. Median PFS (mPFS) time was calculated using Kaplan–Meier survival analysis. Survival curves of the two groups were compared using the two-sided log-rank (Mantel–Cox) test in a single comparison (P < 0.0001). n.r., not reached.