Immune checkpoint blockade resistance in lung cancer: emerging mechanisms and therapeutic opportunities

Identification of genetically engineered strategies to manipulate nano-platforms presenting immunotherapeutic ligands for alleviating primary ovarian insufficiency progression

Primary ovarian insufficiency (POI) is a pathological condition characterized by the early loss of functional ovarian follicles, leading to infertility and systemic consequences affecting reproductive, skeletal, cardiovascular, and neurocognitive helath. Aberrant immune activation, particularly an augmented T cell response in the ovary, plays a critical role in POI pathogenesis. In this context, therapeutic modulation of immune responses through immune checkpoint ligands has garnered interest. In the present study, we identified Lamp2b as an optimal scaffold for engineering extracellular vesicles (EVs). By genetically modifying HEK-293 T-derived EVs to present PD-L1 and Gal-9, enabling them to suppress ovarian autoreactive T lymphocytes and protect ovarian cells from immune-mediated destruction. Functionally, the bioengineered nanoplatform demonstrated potent immunosuppressive effects by promoting apoptosis of effector T cells, reducing intraovarian CD8⁺ T cell infiltration and reinstating serum anti-Müllerian hormone (AMH) levels in POI models. These combined actions effectively halted disease progression, ultimately preventing POI progression and preserving ovarian function.

WO3-x@Ferrocene-Folic Acid Composites Induce Cancer Cell Death and Activate Immunity via PTT/CDT

At present, tumor immune escape is a major problem in the treatment of tumors. The complex network of tumor microenvironments significantly impairs the efficacy of immunotherapy. This paper reports the preparation and immunoantitumor activity of a novel multifunctional defect tungsten trioxide@ferrocene-folic acid composite (WO3-x@Fe-FA) with a high Fenton reaction rate. Ferrocene is modified on the surface of defective trioxide by the covalent coupling method for the first time, and the reaction rate of Fenton is increased by 10 times. WO3-x@Fe-FA induces immunogenic cell death (ICD) through the powerful synergistic anti-tumor effect of PTT/CDT and decomposes H2O2 to produce oxygen through the Fenton reaction, thus down-regulating the expression of immune checkpoint PD-L1 induced by tumor hypoxia. In vitro and in vivo experiments proved that WO3-x@Fe-FA reverses the immunosuppressive tumor microenvironment, transforms the immunosuppressive "cold tumor" into the immune "hot tumor", and activates the immune activity of the system. In vitro and in vivo experiments show that WO3-x@Fe-FA has excellent immunoantitumor activity, and it is expected to be a candidate drug for immunoantitumor therapy.

Potentiating anti-tumor immunity by re-engaging immune synapse molecules

The formation of immune synapses (ISs) between cytotoxic T cells and tumor cells is crucial for effective tumor elimination. However, the role of ISs in immune evasion and resistance to immune checkpoint blockades (ICBs) remains unclear. We demonstrate that ICAM-1, a key IS molecule activating LFA-1 signaling in T and natural killer (NK) cells, is often expressed at low levels in cancers. The absence of ICAM-1 leads to significant resistance to T and NK cell-mediated anti-tumor immunity. Using a CRISPR screen, we show that ICAM-1 is epigenetically regulated by the DNA methylation pathway involving UHRF1 and DNMT1. Furthermore, we engineer an antibody-based therapeutic agent, "LFA-1 engager," to enhance T cell-mediated anti-tumor immunity by reconstituting LFA-1 signaling. Treatment with LFA-1 engagers substantially enhances immune-mediated cytotoxicity, potentiates anti-tumor immunity, and synergizes with ICB in mouse models of ICAM-1-deficient tumors. Our data provide promising therapeutic strategies for re-engaging immune stimulatory signals in cancer immunotherapy.

Obesity promotes immunotherapy efficacy by up-regulating the glycolytic-mediated histone lactacylation modification of CD8+ T cells

The response rate of immune checkpoint blockade (ICB) therapy for non-small-cell lung cancer (NSCLC) remains limited. Recent evidence suggests that obese cancer patients are more likely to benefit from ICB therapy, however, the specific mechanism needs further research. In this study, we found that anti-PD-1 therapy was more effective in obese NSCLC patients compared to normal weight patients and this was verified in mouse NSCLC model. Further bioinformatics analysis indicated that the glycolytic metabolism was markedly elevated in obese NSCLC patients. In vitro co-culture experiment showed that both increased glycolysis of tumor cells and external addition of lactate promoted T cell PD-1 expression. And, PD-1 upregulation was related to monocarboxylate transporter 1 (MCT1)-mediated lactate transport and subsequent lysine lactylation of histones in T cells. Based on the aforementioned data, our study contributes to better application of anti-PD-1 therapy in NSCLC.

Efficient α and β- radionuclide therapy targeting fibroblast activation protein-α in an aggressive preclinical mouse tumour model

PURPOSE

Targeted radionuclide therapy (TRT) is a cancer treatment with relative therapeutic efficacy across various cancer types. We studied the therapeutic potential of TRT using fibroblast activation protein-α (FAP) targeting sdAbs (4AH29) labelled with 225Ac or 131I in immunocompetent mice in a human FAP (hFAP) expressing lung cancer mouse model. We further explored the combination of TRT with programmed cell death ligand 1 (PD-L1) immune checkpoint blockade (ICB).

METHODS

We studied the biodistribution and tumour uptake of [131I]I-GMIB-4AH29 and [225Ac]Ac-DOTA-4AH29 by ex vivo γ-counting. Therapeutic efficacy of [131I]I-GMIB-4AH29 and [225Ac]Ac-DOTA-4AH29 was evaluated in an immunocompetent mouse model. Flow cytometry analysis of tumours from [225Ac]Ac-DOTA-4AH29 treated mice was performed. Treatment with [225Ac]Ac-DOTA-4AH29 was repeated in combination with PD-L1 ICB.

RESULTS

The biodistribution showed high tumour uptake of [131I]I-GMIB-4AH29 with 3.5 ± 0.5% IA/g 1 h post-injection (p.i.) decreasing to 0.9 ± 0.1% IA/g after 24 h. Tumour uptake of [225Ac]Ac-DOTA-4AH29 was also relevant with 2.1 ± 0.5% IA/g 1 h p.i. with a less steep decrease to 1.7 ± 0.2% IA/g after 24 h. Survival was significantly improved after treatment with low and high doses [131I]I-GMIB-4AH29 or [225Ac]Ac-DOTA-4AH29 compared to vehicle solution. Moreover, we observed significantly higher PD-L1 expression in tumours of mice treated with [225Ac]Ac-DOTA-4AH29 compared to vehicle solution. Therefore, we combined high dose [225Ac]Ac-DOTA-4AH29 with PD-L1 ICB showing therapeutic synergy.

CONCLUSION

[225Ac]Ac-DOTA-4AH29 and [131I]I-GMIB-4AH29 exhibit high and persistent tumour targeting, translating into prolonged survival in mice bearing aggressive tumours. Moreover, we demonstrate that the combination of PD-L1 ICB with [225Ac]Ac-DOTA-4AH29 TRT enhances its therapeutic efficacy.

Liquid-liquid phase separation: a new perspective on respiratory diseases

Liquid-liquid phase separation (LLPS) is integral to various biological processes, facilitating signal transduction by creating a condensed, membrane-less environment that plays crucial roles in diverse physiological and pathological processes. Recent evidence has underscored the significance of LLPS in human health and disease. However, its implications in respiratory diseases remain poorly understood. This review explores current insights into the mechanisms and biological roles of LLPS, focusing particularly on its relevance to respiratory diseases, aiming to deepen our understanding and propose a new paradigm for studying phase separation in this context.

Gut microbial metabolites in lung cancer development and immunotherapy: Novel insights into gut-lung axis

Metabolic derivatives of numerous microorganisms inhabiting the human gut can participate in regulating physiological activities and immune status of the lungs through the gut-lung axis. The current well-established microbial metabolites include short-chain fatty acids (SCFAs), tryptophan and its derivatives, polyamines (PAs), secondary bile acids (SBAs), etc. As the study continues to deepen, the critical function of microbial metabolites in the occurrence and treatment of lung cancer has gradually been revealed. Microbial derivates can enter the circulation system to modulate the immune microenvironment of lung cancer. Mechanistically, oncometabolites damage host DNA and promote the occurrence of lung cancer, while tumor-suppresive metabolites directly affect the immune system to combat the malignant properties of cancer cells and even show considerable application potential in improving the efficacy of lung cancer immunotherapy. Considering the crosstalk along the gut-lung axis, in-depth exploration of microbial metabolites in patients' feces or serum will provide novel guidance for lung cancer diagnosis and treatment selection strategies. In addition, targeted therapeutics on microbial metabolites are expected to overcome the bottleneck of lung cancer immunotherapy and alleviate adverse reactions, including fecal microbiota transplantation, microecological preparations, metabolite synthesis and drugs targeting metabolic pathways. In summary, this review provides novel insights and explanations on the intricate interplay between gut microbial metabolites and lung cancer development, and immunotherapy through the lens of the gut-lung axis, which further confirms the possible translational potential of the microbiome metabolome in lung cancer treatment.