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Many reports demonstrate that a high tumor mutation burden (TMB-H) is closely associated with good prognosis of cancer. However, specific studies investigating the association of various TMB statuses with overall survival in patients with solid tumors are scarce.In the present study, we investigated the association of TMB status with overall survival in 5,072 patients with cancer from the HOPE project and clarified the specific mechanism responsible for the good prognosis of the TMB-H group. All tumors were classified into one of four groups based on TMB: ultralow (UL), low (L), intermediate (I) and high (H).The TMB-H group had a better prognosis than the TMB-I and TMB-L groups, but not than the TMB-UL group. Analyzing the expression of 293 immune response-associated genes, 17 genes were up-regulated in the TMB-H group compared to the TMB-I and TNB-L groups, and two genes [CD274 and interferon-γ (IFNG)] were identified as good prognostic factors. Analysis of immune cell populations inside tumors demonstrated that the frequencies of exhausted CD8One possible mechanism for the good prognosis of the TMB-UL group compared to the TMB-H group might be that the TMB-UL group features a balance between immunosuppression and immunostimulation.

Background Project HOPE (High-tech Omics-based Patient Evaluation) has been in progress since 2014 and uses whole-exome sequencing (WES) and gene expression profiling (GEP). Among a total of 1,685 patients with cancer, 13 with melanoma were registered and characterized using multi-omics analyses to investigate specific biomarkers in responders to programmed cell death-1 (PD-1) blockade. Materials and methods The patients with melanoma comprised of six males and seven females, and their mean age was 68 years. Five patients were treated with nivolumab, and two were responders. Results GEP analysis demonstrated that PD-L1 expression was positive in for cases, and melanoma-associated antigens and tumor signaling-associated genes were up-regulated in tumor compared with normal tissues. Additionally, WES analysis indicated more single nucleotide variants (SNVs) per melanoma tumor compared to other tumor types. Remarkably, a case of complete remission after nivolumab therapy showed high expression of PD-L1 protein and the highest number of SNVs. Conclusion The novel approach used in Project HOPE might be an efficient tool that facilitates identifying specific biomarkers predictive of good responders to anti-PD-1 therapy.

A MAGE-1 HLA-A24 peptide-specific CTL line was characterized using a novel staining approach in the case of a metastatic melanoma patient who exhibited a remarkable clinical response in HLA-A24 peptide cocktail-pulsed dendritic cell (DCs) vaccine therapy. Briefly, pre- or post-vaccine peripheral blood mononuclear cells (PBMCs) from the vaccinated patient were stimulated several times with MAGE-1 A24 peptide-pulsed DCs and T2-A24 cells in vitro. Expanded MAGE-1 A24-specific CTL line was investigated in terms of immunological functions. The proportion of MAGE-1 A24 tetramer+ CTLs increased from 0.04% to 18.6%, and the absolute numbers of MAGE-1 tetramer+ CTLs increased up to 5,068-fold after stimulations. Expanded CTL line exhibited a strong cytotoxic activity against MAGE-1+ cancer cell line in the restriction of HLA. Finally, successful identification of MAGE-1 A24 peptide-specific T-cell receptor (TCR) cDNA from anti-TCR MoAbsorted CTL was obtained for the first time and the specific cytotoxicity in TCR gene-transduced naive T-cells was confirmed.