TCF1+PD-1+ tumour-infiltrating lymphocytes predict a favorable response and prolonged survival after immune checkpoint inhibitor therapy for non-small-cell lung cancer.

BACKGROUND: T-cell factor 1 (TCF1)+Programmed cell death-1 (PD-1)+ tumour-infiltrating lymphocytes (TILs) are a recently defined subset of exhausted T-cells (Texh-cells) that exhibit a progenitor phenotype. They have been associated with a response to immune checkpoint inhibitor (ICI) therapy in murine tumour models and in patients with malignant melanoma. We investigated the significance of TCF1+PD-1+ TILs as a predictive biomarker for ICI therapy response in non-small-cell lung cancer (NSCLC). METHODS: Two different cohorts of NSCLC patients treated with ICI targeting the PD-1/PD-L1 pathway were included. RNA-seq was performed using NSCLC tissues obtained from 234 patients prior to immunotherapy (RNA-seq cohort). Double immunostaining of TCF1 and PD-1 and single immunostaining of other immunologic markers were performed in resected tumour tissues from another 116 patients (immunohistochemistry cohort). RESULTS: In the RNA-seq cohort, both Texh-cell and progenitor Texh-cell gene sets were enriched in responders compared with non-responders. Larger Texh-cell fractions and increased progenitor Texh-cell gene sets were significantly associated with better progression-free survival (PFS). In the immunohistochemistry cohort, the TCF1+PD-1+ TIL number and PD-L1 tumour proportion score were significantly higher in responders than in non-responders. A high number of TCF1+PD-1+ TILs was significantly associated with both PFS and overall survival (OS) after ICI therapy, and it independently predicted a better PFS and OS according to multivariate analysis. CONCLUSION: TCF1+PD-1+ TILs, representing progenitor Texh-cells, predict both better response and survival in NSCLC patients after ICI therapy. Thus, they may be a useful predictive biomarker for ICI therapy in NSCLC.

Genetic profiles of subcutaneous panniculitis-like T-cell lymphoma and clinicopathological impact of HAVCR2 mutations.

Recent studies identified germline mutations in HAVCR2 (encoding T-cell immunoglobulin mucin 3) as a genetic factor that predisposes to subcutaneous panniculitis-like T-cell lymphoma (SPTCL). However, the differences between HAVCR2-mutated (HAVCR2MUT) and HAVCR2 wild-type (HAVCR2WT) SPTCLs remain unclear. A nationwide cohort of 53 patients with SPTCL diagnosed at 8 Korean institutions was established. Whole-exome sequencing and RNA-sequencing were performed on 8 patients in the discovery set. In the validation set, targeted gene sequencing or direct sequencing of HAVCR2 was performed. Of 49 patients with available HAVCR2 status, 25 (51.0%) were HAVCR2Y82C. HAVCR2Y82C was associated with younger age (P = .001), development of hemophagocytic lymphohistiocytosis or hemophagocytic lymphohistiocytosis-like systemic illness (P < .001), and short relapse-free survival (RFS) (P = .023). Most mutated genes in SPTCLs were involved in immune responses, epigenetic modifications, and cell signaling. Mutations in UNC13D, PIAS3, and KMT2D were more frequent in HAVCR2WT SPTCLs. At the gene expression level, HAVCR2Y82C SPTCLs were enriched in genes involved in IL6-JAK-STAT3 signaling and in tumor necrosis factor-α signaling via NF-κB. CCR4 was significantly upregulated in HAVCR2WT SPTCLs both at the messenger RNA level and at the protein level. We established a risk stratification system for SPTCL by integrating clinical and histopathological features, including age and HAVCR2 mutation status. This risk stratification system was strongly associated with RFS (P = .031). In conclusion, the HAVCR2Y82C mutation was common in Korean patients with SPTCL and was associated with unique clinicopathological and genetic features. Combining clinicopathological parameters could aid in predicting prognosis for patients with SPTCL.