Immune checkpoint inhibitor (ICI) therapies for tumors of different systems have attained significant achievements and have changed the current situation of tumor treatment due to their therapeutic characteristics of high specificity and low side effects. The immune checkpoint Programmed death 1/Programmed cell death-Ligand 1 (PD-1/PD-L1) axis exerts a vital role in the immune escape of tumor cells. As a result, it has become a key target for tumor immunotherapy. Therefore, to perfect research into potential regulatory factors for the PD-1/PD-L1 axis, in order to understand and illustrate tumor ICI therapy mechanisms, is a significant goal. Moreover, ncRNA has been verified to regulate the PD-1/PD-L1 axis in the tumor immune microenvironment to regulate tumor genesis and development. ncRNAs can improve or decrease the efficacy of ICI therapy by modulating PD-L1 expression. This review aimed to investigate the mechanisms of action of ncRNA in regulating the PD-1/PD-L1 axis in ICI therapy, to provide more efficient immunotherapy for tumors of different systems.

OBJECTIVE: Programmed cell death receptor (ligand)-1 inhibitors (PD-(L)1), as the preferred immunotherapy, have been widely used in the Chinese mainland and drug-induced liver injury (DILI) has been reported. The study aimed to investigate the clinical features or risk factors for immunotherapy-related DILI.
METHODS: Patients who received PD-(L)1 inhibitors from January 2020 to July 2021 were retrospectively reviewed. The likelihood of DILI was adjudicated by the Roussel-Uclaf causality assessment.
RESULTS: A total of 1175 patients were included in the study and 89 patients (7.6%) developed DILI, of which 12 (13.5%) progressed to acute liver failure (ALF) and three (3.4%) died. Among the DILI population, 56 (62.9%) had a cholestatic pattern and exhibited a prolonged treatment course and duration for resolution compared to the hepatocellular and mixed patterns. Hepatocellular carcinoma (HCC), hepatitis B virus (HBV) and abnormal baseline of alkaline phosphatase (ALP) had increased risks of DILI by 2.1-fold (95% confidence interval [CI], 1.231-3.621), 1.9-fold [95% CI, 1.123-3.325] and 2.1-fold [95% CI, 1.317-3.508], respectively. The model for end-stage liver disease (MELD) score had a c-statistic of 0.894 (95% CI, 0.778-1.000) with a sensitivity of 67% and a specificity of 95% for poor outcomes. COX analysis showed that the MELD ≥ 18 was predictive of immunotherapy-related ALF or death.
CONCLUSIONS: PD-(L)1 inhibitor-related liver injury manifests primarily as a cholestatic pattern, on which corticosteroid treatment has minimal effect compared to hepatocellular and mixed patterns. MELD score ≥ 18 at the time of liver injury performed best in the prediction of ALF or death in immune checkpoint inhibitor (ICI)-related DILI.

OBJECTIVE: To analyze the efficacy and adverse effects of anti-PD-1 immune checkpoint inhibitors aimed at nasopharyngeal carcinoma (NPC).
METHODS: During the first stage of the study, using 40 patients with stage III/IVa NPC treated with anti-PD-1 immune checkpoint inhibitors in combination with chemoradiotherapy as a first-line treatment (observation group) and 70 patients with NPC treated with chemoradiotherapy alone (control group). In the second stage of the study, 88 patients with NPC treated with immune checkpoint inhibitors were grouped according to the number of lines of immunotherapy, the number of times, and the types of application.
RESULTS: Observation of the short-term effects in the first stage indicated that the objective response rate (ORR) of the observation group and the control group against primary foci of NPC was 75.0% versus 40.0%; the mortality rate of the observation group was much lower than that of the control group. The overall first-line treatment evaluation of the observation vs. control groups were as follows: ORR (67.5% vs. 38.6%); median PFS (17.52 vs. 17.21 months); and median OS (18.68 vs. 18.14 months), respectively (p < 0.05). The second stage of the study had an ORR of 53.4%, and the efficacy of immunotherapy was related to staging, timing, and frequency.
CONCLUSIONS: Anti-PD-1 immune checkpoint inhibitors combined with chemoradiotherapy as the first-line treatment for nasopharyngeal carcinoma may improve patient outcomes significantly. Timing, frequency, and the type of immunotherapy exerted an effect on the efficacy of immunotherapy. Adverse effects that occurred during treatment were tolerable and controllable.

BACKGROUND: To investigate the sex-based heterogeneity of immune microenvironmental feature and its impact on the response to first-line PD-1 blockade plus chemotherapy in patients with driver-negative advanced or metastatic non-small-cell lung cancer (NSCLC).
METHODS: A total of 439 patients with advanced NSCLC treated with first-line PD-1 blockade plus chemotherapy or chemotherapy were identified. Differences in clinical outcomes between female and male patients were determined using Kaplan-Meier curves. Neoantigen burden and five immune microenvironmental markers expression including PD-L1, CD4, CD8, FOXP3, and CD68 were compared between two groups.
RESULTS: Of 175 eligible patients, 89 received PD-1 blockade plus chemotherapy and 86 received first-line chemotherapy. Forty five were women (25.7%) and 130 were men (74.3%). Female patients received first-line PD-1 blockade in combination with chemotherapy had dramatically better ORR (85.2% vs. 53.2%; p = 0.009), PFS (23.7 vs. 7.3 months; p = 0.013), and OS (46.2 vs. 20.0 months; p = 0.004) than males. Treatment outcomes were similar between females and males in chemotherapy group. Multivariate analyses showed that sex was the independent prognostic factor for patients received PD-1 blockade combined with chemotherapy. Although female patients had significantly lower tumor mutational and neoantigen burden than males, pretreatment tumor tissues of female patients had markedly higher CD4, CD4/FOXP3, and CD4/FOXP3/PD-L1 expression level than male patients.
CONCLUSIONS: Female patients with untreated advanced or metastatic NSCLC would derive a larger benefit from PD-1 blockade in combination with chemotherapy than males. The biological significances of heterogeneity of tumor immune microenvironmental features between them need further investigation.

Tumor cells can express the immune checkpoint protein programmed death-1 (PD-1), but how cancer cell-intrinsic PD-1 is regulated in response to cellular stresses remains largely unknown. Here, we uncover a unique mechanism by which the chemotherapy drug doxorubicin (Dox) regulates cancer cell-intrinsic PD-1. Dox upregulates PD-1 mRNA while reducing PD-1 protein levels in tumor cells. Although Dox shortens the PD-1 half-life, it fails to directly induce PD-1 degradation. Instead, we observe that Dox promotes the interaction between peptide-N(4)-(N-acetyl-beta-glucosaminyl)asparagine amidase (NGLY1) and PD-1, facilitating NGLY1-mediated PD-1 deglycosylation and destabilization. The maintenance of PD-1 sensitizes tumor cells to Dox-mediated antiproliferative effects. Our study unveils a regulatory mechanism of PD-1 in response to Dox and highlights a potential role of cancer cell-intrinsic PD-1 in Dox-mediated antitumor effects.

Malignant melanoma (MM) is a highly aggressive and deadly form of skin cancer, primarily caused by recurrence and metastasis. Therefore, it is crucial to investigate the regulatory mechanisms underlying melanoma recurrence and metastasis. Our study has identified a potential targeted regulatory relationship between LINC02202, miR-526b-3p and XBP1 in malignant melanoma. Through the regulation of the miR-526b-3p/XBP1 signalling pathway, LINC02202 may play a role in tumour progression and immune infiltration and inhibiting the expression of LINC02202 can increase the efficacy of immunotherapy for melanoma. Our findings shed light on the impact of LINC02202/XBP1 on the phenotype and function of malignant melanoma cells. Furthermore, this study provides a theoretical foundation for the development of novel immunotherapy strategies for malignant melanoma.

Immune checkpoint inhibitors (ICIs) have shown promising efficacy in multiple cancers including biliary tract cancers (BTCs). However, the data focusing on the efficacy of ICIs in patients with gallbladder cancer (GBC) is still limited. In this study, we aim to assess the efficacy of ICIs in GBC and explore the clinicopathologic and molecular markers associated with ICI benefit. We retrospective analyzed 69 GBC patients who had received ICI therapy between January 2016 and December 2020. Tumor samples were obtained for genomic sequencing and immunohistochemical analysis. The median progression-free survival (PFS) and overall survival (OS) was 4.4 months and 8.5 months, respectively. Multivariate analysis indicated that alcohol intake history, carcinoma embryonic antigen (CEA) level ≥100 U/mL, and cutaneous immune-related adverse events (irAEs) were independent prognostic factors for PFS. CEA level ≥100 U/mL and cutaneous irAEs were independent prognostic factors for OS. The objective response rate and disease control rate (DCR) were 15.9% and 37.7%, respectively. Patients with cutaneous irAEs, high CD8+ T cell infiltrated or immune inflamed GBCs had higher DCR. Patients with high CD8+ T cell infiltrated or immune inflamed GBCs also had a notably improved prognosis. These results suggest that ICIs were effective in patients with GBC. High CEA level, cutaneous irAEs, high CD8+ T cell infiltration, and immune inflamed phenotype could be useful for predicting the efficacy of ICIs in GBC.

The induction of cuproptosis, a recently identified form of copper-dependent immunogenic cell death, is a promising approach for antitumor therapy. However, sufficient accumulation of intracellular copper ions (Cu2+) in tumor cells is essential for inducing cuproptosis. Herein, an intelligent cuproptosis-inducing nanosystem is constructed by encapsulating copper oxide (CuO) nanoparticles with the copper ionophore elesclomol (ES). After uptake by tumor cells, ES@CuO is degraded to release Cu2+ and ES to synergistically trigger cuproptosis, thereby significantly inhibiting the tumor growth of murine B16 melanoma cells. Moreover, ES@CuO further promoted cuproptosis-mediated immune responses and reprogrammed the immunosuppressive tumor microenvironment by increasing the number of tumor-infiltrating lymphocytes and secreted inflammatory cytokines. Additionally, combining ES@CuO with programmed cell death-1 (PD-1) immunotherapy substantially increased the antitumor efficacy in murine melanoma. Overall, the findings of this study can lead to the use of a novel strategy for cuproptosis-mediated antitumor therapy, which may enhance the efficacy of immune checkpoint inhibitor therapy.

Immune system imbalances contribute to the pathogenesis of several different diseases, and immunotherapy shows great therapeutic efficacy against tumours and infectious diseases with immune-mediated derivations. In recent years, molecules targeting the programmed cell death protein 1 (PD-1) immune checkpoint have attracted much attention, and related signalling pathways have been studied clearly. At present, several inhibitors and antibodies targeting PD-1 have been utilized as anti-tumour therapies. However, increasing evidence indicates that PD-1 blockade also has different degrees of adverse side effects, and these new explorations into the therapeutic safety of PD-1 inhibitors contribute to the emerging concept that immune normalization, rather than immune enhancement, is the ultimate goal of disease treatment. In this review, we summarize recent advancements in PD-1 research with regard to immune normalization and targeted therapy.

Immune checkpoints (ICPs) can promote tumor growth and prevent immunity-induced cancer cell apoptosis. Fortunately, targeting ICPs, such as programmed cell death 1 (PD-1) or cytotoxic T lymphocyte associated protein 4 (CTLA-4), has achieved great success in the past few years and has gradually become an effective treatment for cancers, including hepatocellular carcinoma (HCC). However, many patients do not respond to ICP therapy due to acquired resistance and recurrence. Therefore, clarifying the specific mechanisms of ICP in the development of HCC is very important for enhancing the efficacy of anti-PD-1 and anti-CTLA-4 therapy. In particular, antigen presentation and interferon-γ (IFN-γ) signaling were reported to be involved in the development of resistance. In this review, we have explained the role and regulatory mechanisms of ICP therapy in HCC pathology. Moreover, we have also elaborated on combinations of ICP inhibitors and other treatments to enhance the antitumor effect. Collectively, recent advances in the pharmacological targeting of ICPs provide insights for the development of a novel alternative treatment for HCC.