The combination of oxaliplatin and anti-PD-1 inhibitor promotes immune cells infiltration and enhances anti-tumor effect of PD-1 blockade in bladder cancer

Patient-derived Immunocompetent Tumor Organoids: A Platform for Chemotherapy Evaluation in the Context of T-cell Recognition

Most of the anticancer compounds synthesized by chemists are primarily evaluated for their direct cytotoxic effects at the cellular level, often overlooking the critical role of the immune system. In this study, we developed a patient-derived, T-cell-retaining tumor organoid model that allows us to evaluate the anticancer efficacy of chemical drugs under the synergistic paradigm of antigen-specific T-cell-dependent killing, which may reveal the missed drug hits in the simple cytotoxic assay. We evaluated clinically approved platinum (Pt) drugs and a custom library of twenty-eight PtIV compounds. We observed low direct cytotoxicity of Pt drugs, but variable synergistic effects in combination with immune checkpoint inhibitors (ICIs). In contrast, the majority of PtIV compounds exhibited potent tumor-killing capabilities. Interestingly, several PtIV compounds went beyond direct tumor killing and showed significant immunosynergistic effects with ICIs, outstanding at sub-micromolar concentrations. Among these, Pt-19, PtIV compounds with cinnamate axial ligands, emerged as the most therapeutically potent, demonstrating pronounced immunosynergistic effects by promoting the release of cytotoxic cytokines, activating immune-related pathways and enhancing T cell receptor (TCR) clonal expansion. Overall, this initiative marks the first use of patient-derived immunocompetent tumor organoids to explore and study chemotherapy, advancing their path toward more effective small molecule drug discovery.

A PD-L1xCD3 bispecific nanobody as a novel T-cell engager in treating PD-L1 overexpression melanoma

The development of Immune checkpoint blockade(ICB) therapy and BRAF- and MEK-targeted therapies has reshaped the survival outcomes of the patients with advanced melanoma. PD-1/PD-L1 blockade was an approved strategy in melanoma treatment. Here we design a PD-L1 xCD3 nanobody as a novel bispecific T cell engager (BiTE) in treating PD-L1 overexpression melanoma. BiTE PD-L1×CD3 Nb was predicted to bind near a large acidic surface on CD3-ε similar to UCHT1-scFv antibody based on alpha-fold and molecular docking. BiTE PD-L1×CD3 Nb and anti-CD3 Nb retained the ability to activate T cells to produce TNF-α and IFN-γ in a dose-dependent manner. The IC50 value of BiTE PD-L1×CD3 Nb was 4.208μg/mL. BiTE PD-L1×CD3 Nb showed obvious cytotoxic activity on both A375WT and A375PD-L1 related to PD-L1 expression level.