HDL-cholesterol confers sensitivity of immunotherapy in nasopharyngeal carcinoma via remodeling tumor-associated macrophages towards the M1 phenotype.

BACKGROUND: The sustained effectiveness of anti-programmed cell death protein-1/programmed death-ligand 1 treatment is limited to a subgroup of patients with advanced nasopharyngeal carcinoma (NPC), and the specific biomarker determining the response to immunotherapy in NPC remains uncertain. METHODS: We assessed the associations between pre-immunotherapy and post-immunotherapy serum lipoproteins and survival in a training cohort (N=160) and corroborated these findings in a validation cohort (N=100). Animal studies were performed to explore the underlying mechanisms. Additionally, the relationship between high-density lipoprotein-cholesterol (HDL-C) levels and M1/M2-like macrophages, as well as activated CD8+T cells in tumor tissues from patients with NPC who received immunotherapy, was investigated. RESULTS: The lipoproteins cholesterol, HDL-C, low-density lipoprotein-cholesterol, triglycerides, apolipoprotein A-1 (ApoA1), and apolipoprotein B, were significantly altered after immunotherapy. Patients with higher baseline HDL-C or ApoA1, or those with increased HDL-C or ApoA1 after immunotherapy had longer progression-free survival, a finding verified in the validation cohort (p<0.05). Multivariate analysis revealed that baseline HDL-C and elevated HDL-C post-immunotherapy were independent predictors of superior PFS (p<0.05). Furthermore, we discovered that L-4F, an ApoA1 mimetic, could inhibit tumor growth in NPC xenografts. This effect was associated with L-4F's ability to polarize M2-like macrophages towards an M1-like phenotype via the activation of mitogen-activated protein kinase (MAPK) p38 and nuclear factor-κB (NF-κB) p65, thereby alleviating immunosuppression in the tumor microenvironment. Importantly, in patients with NPC with high plasma HDL-C levels, the number of M2-like macrophages was significantly decreased, while M1-like macrophages and activated CD8+T cells were notably increased in those with high HDL-C levels. CONCLUSION: Higher baseline HDL-C levels or an increase in HDL-C post-immunotherapy can enhance immunotherapeutic responses in patients with NPC by reprogramming M2-like macrophages towards the M1 phenotype. This suggests a potential role for prospectively exploring ApoA1 mimetics as adjuvant agents in combination with immunotherapy.

PQR309, a dual PI3K/mTOR inhibitor, synergizes with gemcitabine by impairing the GSK-3ß and STAT3/HSP60 signaling pathways to treat nasopharyngeal carcinoma.

End-stage nasopharyngeal carcinoma (NPC) has unsatisfactory survival. The limited benefit of chemotherapy and the scarcity of targeted drugs are major challenges in NPC. New approaches to treat late-stage NPC are urgently required. In this study, we explored whether the dual PI3K/mTOR inhibitor, PQR309, exerted a favorable antineoplastic effect and sensitized the response to gemcitabine in NPC. We observed that PI3K expression was positive and elevated in 14 NPC cell lines compared with that in normal nasopharygeal cell lines. Patients with NPC with higher PI3K levels displayed poorer prognosis. We subsequently showed that PQR309 alone effectively decreased the viability, invasiveness, and migratory capability of NPC cells and neoplasm development in mice xenograft models, and dose-dependently induced apoptosis. More importantly, PQR309 remarkably strengthened the anti-NPC function of gemcitabine both in vivo and in vitro. Mechanistically, PQR309 sensitized NPC to gemcitabine by increasing caspase pathway-dependent apoptosis, blocking GSK-3ß and STAT3/HSP60 signaling, and ablating epithelial-mesenchyme transition. Thus, targeting PI3K/mTOR using PQR309 might represent a treatment option to promote the response to gemcitabine in NPC, and provides a theoretical foundation for the study of targeted drugs combined with chemotherapy for NPC.

The BCL-2 inhibitor APG-2575 resets tumor-associated macrophages toward the M1 phenotype, promoting a favorable response to anti-PD-1 therapy via NLRP3 activation.

The main challenges in the use of immune checkpoint inhibitors (ICIs) are ascribed to the immunosuppressive tumor microenvironment and the lack of sufficient infiltration of activated CD8+ T cells. Transforming the tumor microenvironment (TME) from "cold" to "hot" and thus more likely to potentiate the effects of ICIs is a promising strategy for cancer treatment. We found that the selective BCL-2 inhibitor APG-2575 can enhance the antitumor efficacy of anti-PD-1 therapy in syngeneic and humanized CD34+ mouse models. Using single-cell RNA sequencing, we found that APG-2575 polarized M2-like immunosuppressive macrophages toward the M1-like immunostimulatory phenotype with increased CCL5 and CXCL10 secretion, restoring T-cell function and promoting a favorable immunotherapy response. Mechanistically, we demonstrated that APG-2575 directly binds to NF-κB p65 to activate NLRP3 signaling, thereby mediating macrophage repolarization and the activation of proinflammatory caspases and subsequently increasing CCL5 and CXCL10 chemokine production. As a result, APG-2575-induced macrophage repolarization could remodel the tumor immune microenvironment, thus improving tumor immunosuppression and further enhancing antitumor T-cell immunity. Multiplex immunohistochemistry confirmed that patients with better immunotherapeutic efficacy had higher CD86, p-NF-κB p65 and NLRP3 levels, accompanied by lower CD206 expression on macrophages. Collectively, these data provide evidence that further study on APG-2575 in combination with immunotherapy for tumor treatment is required.

Predictive value of immunotherapy-induced inflammation indexes: dynamic changes in patients with nasopharyngeal carcinoma receiving immune checkpoint inhibitors.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have achieved substantial advancements in clinical care. However, there is no strong evidence for identified biomarkers of ICIs in NPC. METHODS: In this retrospective study, 284 patients were enrolled into a training or validation cohort. Inflammatory indexes based on peripheral blood parameters were evaluated, including the systemic immune-inflammation index (SII), the neutrophil-lymphocyte ratio (NLR), the platelet-lymphocyte ratio (PLR), the lymphocyte-to-C-reactive protein ratio (LCR), and the lymphocyte-monocyte ratio (LMR). The optimum cut-off value for patient stratification was identified using X-tile. The Kaplan-Meier method and Cox's proportional regression analyses were used to identify prognostic factors. RESULTS: Immunotherapy significantly changed the levels of SII, NLR, PLR, LCR and LMR in NPC patients. Patients with lower SII, NLR, and PLR, as well as those with higher LCR and LMR, before immunotherapy had superior PFS (all p < 0.05). Moreover, PFS in the decreased SII, reduced NLR and increased LMR group was significantly longer than in the opposite group (all p < 0.05). Both univariate and multivariate analyses validated that baseline SII and LMR, and the immunotherapy-related SII reduction and LMR elevation were independent prognostic factors for PFS in advanced NPC patients receiving ICIs. CONCLUSIONS: Immune checkpoint inhibitor treatments significantly changed the levels of SII, NLR, PLR, LCR and LMR in NPC patients treated with immunotherapy. A lower baseline SII and a higher baseline LMR, and a reduction in SII and an elevation in LMR after immunotherapy are favorable factors for predicting survival among advanced NPC patients.

There is no strong evidence for identified biomarkers of immune checkpoint inhibitors (ICIs) in nasopharyngeal carcinoma (NPC).Lower baseline SII and higher baseline LMR were related to better PFS. The dynamic changes of SII and LMR were independent prognostic factors for the survival of NPC patients receiving ICIs.Neutrophils, platelets, lymphocytes, and monocytes can be used as cheap and valuable biomarkers for predicting tumor response in NPC on immunotherapy.