The ICBcircSig score was established based on the weighted expression of circTMTC3 and circFAM117B from melanoma in cohorts treated with anti-PD-1 or combined anti-CTLA4 and anti-PD1 therapy and showed that the ICBcircSig core model can serve as a robust predictor of the efficacy of immunotherapy in patients with melanoma. Here, CTLA4 is linked to melanoma.