This study (ORIENT-4) aimed to assess the efficacy and safety of sintilimab, a humanized anti-PD-1 antibody, in patients with relapsed/refractory extranodal NK/T cell lymphoma (r/r ENKTL). ORIENT-4 is a multicenter, single-arm, phase 2 clinical trial (NCT03228836). Patients with r/r ENKTL who failed to at least one asparaginase-based regimen were enrolled to receive sintilimab 200 mg intravenously every 3 weeks for up to 24 months. The primary endpoint was the objective response rate (ORR) based on Lugano 2014 criteria. Twenty-eight patients with r/r ENKTL were enrolled from August 31, 2017 to February 7, 2018. Twenty-one patients (75.0%, 95% CI: 55.1–89.3%) achieved an objective response. With a median follow-up of 30.4 months, the median overall survival (OS) was not reached. The 24-month OS rate was 78.6% (95% CI, 58.4–89.8%). Most treatment-related adverse events (TRAEs) were grade 1–2 (71.4%), and the most common TRAE was decreased lymphocyte count (42.9%). Serious adverse events (SAEs) occurred in 7 (25.0%) patients, and no patient died of adverse events. Sintilimab is effective and well tolerated in patients with r/r ENKTL and could be a novel therapeutic approach for the control of ENKTL in patients.

Chronic lymphocytic leukemia (CLL) is a hematological malignancy with high metabolic heterogeneity. N6‐methyladenosine (m6A) modification plays an important role in metabolism through regulating circular RNAs (circRNAs). However, the underlying mechanism is not yet fully understood in CLL. Herein, an m6A scoring system and an m6A‐related circRNA prognostic signature are established, and circTET2 as a potential prognostic biomarker for CLL is identified. The level of m6A modification is found to affect the transport of circTET2 out of the nucleus. By interacting with the RNA‐binding protein (RBP) heterogeneous nuclear ribonucleoprotein C (HNRNPC), circTET2 regulates the stability of CPT1A and participates in the lipid metabolism and proliferation of CLL cells through mTORC1 signaling pathway. The mTOR inhibitor dactolisib and FAO inhibitor perhexiline exert a synergistic effect on CLL cells. In addition, the biogenesis of circTET2 can be affected by the splicing process and the RBPs RBMX and YTHDC1. CP028, a splicing inhibitor, modulates the expression of circTET2 and shows pronounced inhibitory effects. In summary, circTET2 plays an important role in the modulation of lipid metabolism and cell proliferation in CLL. This study demonstrates the clinical value of circTET2 as a prognostic indicator as well as provides novel insights in targeting treatment for CLL.

Cytopenia is one of the most common adverse events following the CAR-T cell infusion, affecting the quality of life and potentially leading to life-threatening bleeding and infection. This study ai...

T-cell large granular lymphocytic leukemia (T-LGLL) is a rare lymphoproliferative disorder and can cooccur in the context of pure red cell aplasia (PRCA). The aim of the current study was to analyze the signal transducer and activator of transcription 3 (STAT3) mutation status and its clinical significance in T-LGLL. We found STAT3 mutations in 21.4% of patients with T-LGLL. High β2-MG (β2-microglobulin) levels (P = 0.005), neutropenia (P = 0.018) and PRCA (P = 0.001) all displayed a significant association with STAT3 mutations. In univariate analysis, treatment-free survival (TFS) was affected by STAT3 mutation status (P = 0.008) and β2-MG (P = 0.006). Our results demonstrate the remarkable correlation of STAT3 mutation with PRCA, neutropenia and β2-MG.

Peripheral T‐cell lymphoma (PTCL) is a highly heterogeneous group of mature T‐cell malignancies. The efficacy of current first‐line treatment is dismal, and novel agents are urgently needed to improve patient outcomes. A close association between the cyclic GMP‐AMP synthase‐stimulator of interferon genes (cGAS‐STING) pathway and tumor promotion exists, revealing prospective therapeutic targets. This study, investigates the role of the cGAS‐STING pathway and its underlying mechanisms in PTCL progression. Single‐cell RNA sequencing showes that the cGAS‐STING pathway is highly expressed and closely associated with PTCL proliferation. cGAS inhibition suppresses tumor growth and impaires DNA damage repair. Moreover, Cdc2‐like kinase 1 (CLK1) is critical for residual tumor cell survival after treatment with cGAS inhibitors, and CLK1 suppression enhances sensitivity to cGAS inhibitors. Single‐cell dynamic transcriptomic analysis indicates reduced proliferation‐associated nascent RNAs as the underlying mechanism. In first‐line therapy, chemotherapy‐triggered DNA damage activates the cGAS‐STING pathway, and cGAS inhibitors can synergize with chemotherapeutic agents to kill tumors. The cGAS‐STING pathway is oncogenic in PTCL, whereas targeting cGAS suppresses tumor growth, and CLK1 may be a sensitivity indicator for cGAS inhibitors. These findings provide a theoretical foundation for optimizing therapeutic strategies for PTCL, especially in patients with relapsed/refractory disease.