Reprogramming of myeloid cells and their progenitors in patients with non-medullary thyroid carcinoma

Single-cell immune aging clocks reveal inter-individual heterogeneity during infection and vaccination

Aging affects human immune system functionality, increasing susceptibility to immune-mediated diseases. While gene expression programs accurately reflect immune function, their relationship with biological immune aging and health status remains unclear. Here we developed robust, cell-type-specific aging clocks (sc-ImmuAging) for the myeloid and lymphoid immune cell populations in circulation within peripheral blood mononuclear cells, using single-cell RNA-sequencing data from 1,081 healthy individuals aged from 18 to 97 years. Application of sc-ImmuAging to transcriptome data of patients with COVID-19 revealed notable age acceleration in monocytes, which decreased during recovery. Furthermore, inter-individual variations in immune aging induced by vaccination were identified, with individuals exhibiting elevated baseline interferon response genes showing age rejuvenation in CD8+ T cells after BCG vaccination. sc-ImmuAging provides a powerful tool for decoding immune aging dynamics, offering insights into age-related immune alterations and potential interventions to promote healthy aging.

Thyroid Cancer-The Tumor Immune Microenvironment (TIME) over Time and Space

In thyroid cancer, the tumor immune microenvironment (TIME) plays a crucial role in cancer development, progression and response to treatment. Like many other cancers, thyroid cancer creates a complex network of interactions with immune cells directly (cell-to-cell) and via humoral mediators (i.e., cytokines). This dynamic microenvironment undergoes constant modification, which can lead to changes in the immunophenotype that might explain cancer progression, dedifferentiation and resistance to treatment. According to the cancer immunoediting hypothesis, cancerous tumors can shape their immune microenvironment to create an immunosuppressive milieu that allows them to evade classic immune surveillance. One mechanism by which this occurs is through the reprogramming of immune cells, often shifting their phenotypes from cytotoxic to regulatory. Recent research has shed light on cellular components and molecular interactions within the thyroid cancer TIME. Immune cells such as Tumor-Associated Lymphocytes (TALs), myeloid-derived suppressor cells (MDSCs), Tumor-Associated Macrophages (TAMs) and Double-Negative (DN) T cells seem to play key roles in shaping the immune response to thyroid cancer. Additionally, cytokines, chemokines and other signaling molecules contribute to the communication and regulation of immune cells within that microenvironment. By studying these interactions, researchers aim to uncover not just potential therapeutic targets but also biomarkers of thyroid cancer that could provide clues on severity and progression. Based on that knowledge, strategies such as the use of immune checkpoint inhibitors, antigen-specific targeted immunotherapies, and immunomodulatory agents are being explored to enhance the anti-tumor immune response and overcome cancer immunosuppressive mechanisms. In this review, we analyze the available literature and provide our own experience to unravel the complexity of the thyroid immune microenvironment. Continued research in this area holds promise for improving outcomes through the identification of immune markers of severity/progression of thyroid cancer and the development of innovative immunotherapeutic approaches.

Polymersomes with splenic avidity target red pulp myeloid cells for cancer immunotherapy

Regulating innate immunity is an emerging approach to improve cancer immunotherapy. Such regulation requires engaging myeloid cells by delivering immunomodulatory compounds to hematopoietic organs, including the spleen. Here we present a polymersome-based nanocarrier with splenic avidity and propensity for red pulp myeloid cell uptake. We characterized the in vivo behaviour of four chemically identical yet topologically different polymersomes by in vivo positron emission tomography imaging and innovative flow and mass cytometry techniques. Upon intravenous administration, relatively large and spherical polymersomes accumulated rapidly in the spleen and efficiently targeted myeloid cells in the splenic red pulp. When loaded with β-glucan, intravenously administered polymersomes significantly reduced tumour growth in a mouse melanoma model. We initiated our nanotherapeutic's clinical translation with a biodistribution study in non-human primates, which revealed that the platform's splenic avidity is preserved across species.

Efficacy and safety of immune checkpoint inhibitors for advanced non-small cell lung cancer with leptomeningeal metastases harboring targetable mutations

Background

Driver gene-positive non-small cell lung cancer (NSCLC) patients are prone to develop leptomeningeal metastasis (LM), leading to an extremely high mortality. The objective of this study was to assess the efficacy and safety of immune checkpoint inhibitors (ICIs) treatments for patients with NSCLC and LM harboring targetable mutations.

Methods

We retrospectively collected records of patients with NSCLC harboring targetable mutations and prescribed ICIs following the diagnosis of LM at Huashan Hospital, Fudan University. In addition, we reviewed relevant literature and enrolled patients who met the inclusion criteria. Clinical characteristics were statistically analyzed, and the Kaplan-Meier method and log-rank test were employed to assess the median progression-free survival (mPFS) and median overall survival (mOS).

Results

A total of 37 patients with NSCLC harboring targetable mutations who received ICIs after LM diagnosis were included. The median age of the enrolled patients was 54 years (range, 33-70 years), and 62.2% were female. Following ICI administration, the intracranial objective response rate (iORR) and intracranial disease control rate (iDCR) for all enrolled patients were 18.9% and 62.2%, respectively. The mPFS of all patients was 2.5 months [95% confidence interval (CI): 2.166-2.834 months] and the mOS was 5.8 months (95% CI: 5.087-6.513 months). Both univariate and multivariate analyses revealed a significant increase in mOS or individuals who had previously undergone cranial radiation therapy compared to those who had not. Furthermore, different histology molecular types were found to be potentially associated with survival time.

Conclusions

Some patients with NSCLC harboring targetable gene mutations following LM diagnosis may benefit from ICI treatment with relatively good tolerance. However, further screening of the most suitable patient populations for ICIs is required.

A Comparative Analysis of NOX4 Protein Expression in Malignant and Non-Malignant Thyroid Tumors

The comparative analysis of the expression of the reactive oxygen species-generating NADPH oxidase NOX4 from TCGA data shows that the NOX4 transcript is upregulated in papillary thyroid carcinomas (PTC)-BRAF^V600E tumors compared to PTC-BRAF^wt tumors. However, a comparative analysis of NOX4 at the protein level in malignant and non-malignant tumors is missing. We explored NOX4 protein expression by immunohistochemistry staining in malignant tumors (28 classical forms of PTC (C-PTC), 17 follicular variants of PTC (F-PTC), and three anaplastic thyroid carcinomas (ATCs)) and in non-malignant tumors (six lymphocytic thyroiditis, four Graves' disease, ten goiters, and 20 hyperplasias). We detected the BRAF^V600E mutation by Sanger sequencing and digital droplet PCR. The results show that NOX4 was found to be higher (score ≥ 2) in C-PTC (92.9%) compared to F-PTC (52.9%) and ATC (33.3%) concerning malignant tumors. Interestingly, all C-PTC-BRAF^V600E expressed a high score for NOX4 at the protein level, strengthening the positive correlation between the BRAF^V600E mutation and NOX4 expression. In addition, independent of the mutational status of BRAF, we observed that 90% of C-PTC infiltrating tumors showed high NOX4 expression, suggesting that NOX4 may be considered a complementary biomarker in PTC aggressiveness. Interestingly, NOX4 was highly expressed in non-malignant thyroid diseases with different subcellular localizations.

Hematologic dysfunction in cancer: Mechanisms, effects on antitumor immunity, and roles in disease progression

With the major advances in cancer immunology and immunotherapy, it is critical to consider that most immune cells are short-lived and need to be continuously replenished from hematopoietic stem and progenitor cells. Hematologic abnormalities are prevalent in cancer patients, and many ground-breaking studies over the past decade provide insights into their underlying cellular and molecular mechanisms. Such studies demonstrate that the dysfunction of hematopoiesis is more than a side-effect of cancer pathology, but an important systemic feature of cancer disease. Here we review these many advances, covering the cancer-associated phenotypes of hematopoietic stem and progenitor cells, the dysfunction of myelopoiesis and erythropoiesis, the importance of extramedullary hematopoiesis in cancer disease, and the developmental origins of tumor associated macrophages. We address the roles of many secreted mediators, signaling pathways, and transcriptional and epigenetic mechanisms that mediate such hematopoietic dysfunction. Furthermore, we discuss the important contribution of the hematopoietic dysfunction to cancer immunosuppression, the possible avenues for therapeutic intervention, and highlight the unanswered questions and directions for future work. Overall, hematopoietic dysfunction is established as an active component of the cancer disease mechanisms and an important target for therapeutic intervention.