biostudies-literatureAsquino ASapienza Università di Roma316https://www.ebi.ac.uk/biostudies/studies/S-EPMC12676864biostudies-literatureUnknown44(1)<h4>Background</h4>Recurrent/metastatic head and neck squamous cell carcinoma ((R/M) HNSCC) represents one of the most aggressive and immunosuppressive cancers. Despite the introduction of immune checkpoint inhibitors (ICIs), only a limited number of patients obtain long-term benefits. In (R/M) HNSCC patients, the antitumor immune response is defective, conferring resistance and promoting tumor progression. Therefore, the identification of novel biomarkers for superior clinical outcomes and easily accessible in standard clinical settings is still an unmet clinical need.<h4>Methods</h4>Blood liquid biopsies obtained from (R/M) HNSCC patients undergoing pembrolizumab therapy (monotherapy or in combination with chemotherapy) were analyzed by flow cytometry to evaluate the levels of circulatinJournal of experimental & clinical cancer research : CRCirculating CD137⁺Treg cells and LOX-1⁺PMN-MDSCs as biomarkers of immunotherapy resistance in (R/M) HNSCC patients.PMC12676864RG123188B4C6C54BRM123188C3F3E706RM124191094FCF86Strigari LSantini DNuti MRughetti ABallario ABotticelli ACirillo AZizzari IGNapoletano CAsquino ATuosto LPace AValentino FfalseCirculating CD137⁺Treg cells and LOX-1⁺PMN-MDSCs as biomarkers of immunotherapy resistance in (R/M) HNSCC patients.<h4>Background</h4>Recurrent/metastatic head and neck squamous cell carcinoma ((R/M) HNSCC) represents one of the most aggressive and immunosuppressive cancers. Despite the introduction of immune checkpoint inhibitors (ICIs), only a limited number of patients obtain long-term benefits. In (R/M) HNSCC patients, the antitumor immune response is defective, conferring resistance and promoting tumor progression. Therefore, the identification of novel biomarkers for superior clinical outcomes and easily accessible in standard clinical settings is still an unmet clinical need.<h4>Methods</h4>Blood liquid biopsies obtained from (R/M) HNSCC patients undergoing pembrolizumab therapy (monotherapy or in combination with chemotherapy) were analyzed by flow cytometry to evaluate the levels of circulatin2025-01-01T00:00:00Z2025 Dec2026-06-05T22:25:03.897Z2026-05-22T03:16:10.008ZS-EPMC126768644134015410.1186/s13046-025-03574-6