Indoleamine 2,3-Dioxygenase (IDO) Activity: A Perspective Biomarker for Laboratory Determination in Tumor Immunotherapy

Annexin A1: a key regulator of T cell function and bone marrow adiposity in aplastic anaemia

This study investigates the role of Annexin A1 (ANXA1) in regulating T cell function and its implications in bone marrow adiposity in aplastic anaemia (AA). Utilizing single-cell sequencing analysis, we compared bone marrow tissues from AA patients and healthy individuals, focusing on T cell subgroups and their impact on bone marrow pathology. Our findings reveal a significant activation of CD8+ T cells in AA, driven by reduced ANXA1 expression. This heightened T cell activity promotes adipogenesis in bone marrow-derived mesenchymal stem cells via IFN-γ secretion. Overexpression of ANXA1 was found to suppress this process, suggesting its therapeutic potential in AA treatment. The study highlights ANXA1 as a crucial regulator in the AA-associated immune microenvironment and bone marrow adiposity. KEY POINTS: This study found that ANXA1 is significantly downregulated in AA and provides detailed insights into its critical role in the disease. The study demonstrates the excessive activation of CD8+ T cells in the progression of AA. The research shows that the overexpression of ANXA1 can effectively inhibit the activation of CD8+ T cells. The study confirms that overexpression of ANXA1 reduces the secretion of the cytokine IFN-γ, decreases adipogenesis in bone marrow-derived mesenchymal stem cells and may improve AA symptoms. This research provides new molecular targets for the treatment of AA.

Tetrahydroisoquinolines - an updated patent review for cancer treatment (2016 - present)

INTRODUCTION

Cancer is a prominent cause of death globally, triggered by both non-genetic and genetic alterations in genes influenced by various environmental factors. The tetrahydroisoquinoline (THIQ), specifically 1,2,3,4-tetrahydroisoquinoline serves as fundamental element in various alkaloids, prevalent in proximity to quinoline and indole alkaloids.

AREA COVERED

In this review, the therapeutic applications of THIQ derivatives as an anticancer agent from 2016 to 2024 have been examined. The patents were gathered through comprehensive searches of the Espacenet, Google patent, WIPO, and Sci Finder databases. The therapeutic areas encompassed in the patents include numerous targets of cancer.

EXPERT OPINION

THIQ analogues play a crucial role in medicinal chemistry, with many being integral to pharmacological processes and clinical trials. Numerous THIQ compounds have been synthesized for therapeutic purposes, notably in cancer treatment. They show great promise for developing anticancer drugs, demonstrating strong affinity and efficacy against various cancer targets. The creation of multi-target ligands is a compelling avenue for THIQ-based anticancer drug discovery.

IDO1 inhibitors are synergistic with CXCL10 agonists in inhibiting colon cancer growth

Indoleamine 2,3-dioxygenase 1 (IDO1) is an immune checkpoint that degrades L-tryptophan to kynurenine (Kyn) and enhance immunosuppression, which can be an attractive target for treating colon cancer. IDO1 inhibitors have limited efficacy when used as monotherapies, and their combination approach has been shown to provide synergistic benefits. Many studies have shown that targeting chemokines can promote the efficacy of immune checkpoint inhibitors. Therefore, this study explored the use of IDO1 inhibitors with multiple chemokines to develop a new combination regimen for IDO1 inhibitors. We found that IDO1 inhibitors reduce the secretion of C-X-C motif ligand 10(CXCL10) in cancer cells, and CXCL10 supplementation significantly improved the anticancer effect of IDO1 inhibitors. The combination of the IDO1 inhibitor with CXCL10 or its agonist axitinib had a synergistic inhibitory effect on the growth of colon cancer cells and transplanted CT26 tumors. This synergistic effect may be achieved by inhibiting cancer cell proliferation, promoting cancer cell apoptosis, promoting CD8+T cell differentiation and decreasing Tregs. Two downstream pathways of IDO1 affect CXCL10 secretion. One being the Kyn-aryl hydrocarbon receptor (AHR) pathway, the other is the general control nonderepressible 2(GCN2). Our study provides a new reference for combination regimens of IDO1 inhibitors.

The Interplay between Metabolic Adaptations and Diet in Cancer Immunotherapy

Over the past decade, cancer immunotherapy has significantly advanced through the introduction of immune checkpoint inhibitors and the augmentation of adoptive cell transfer to enhance the innate cancer defense mechanisms. Despite these remarkable achievements, some cancers exhibit resistance to immunotherapy, with limited patient responsiveness and development of therapy resistance. Metabolic adaptations in both immune cells and cancer cells have emerged as central contributors to immunotherapy resistance. In the last few years, new insights emphasized the critical role of cancer and immune cell metabolism in animal models and patients. During therapy, immune cells undergo important metabolic shifts crucial for their acquired effector function against cancer cells. However, cancer cell metabolic rewiring and nutrient competition within tumor microenvironment (TME) alters many immune functions, affecting their fitness, polarization, recruitment, and survival. These interactions have initiated the development of novel therapies targeting tumor cell metabolism and favoring antitumor immunity within the TME. Furthermore, there has been increasing interest in comprehending how diet impacts the response to immunotherapy, given the demonstrated immunomodulatory and antitumor activity of various nutrients. In conclusion, recent advances in preclinical and clinical studies have highlighted the capacity of immune-based cancer therapies. Therefore, further exploration into the metabolic requirements of immune cells within the TME holds significant promise for the development of innovative therapeutic approaches that can effectively combat cancer in patients.

Non-invasive biomarkers of acute rejection in pediatric kidney transplantation: New targets and strategies

Kidney transplantation is the preferred treatment for pediatric end-stage renal disease. However, pediatric recipients face unique challenges due to their prolonged need for kidney function to accommodate growth and development. The continual changes in the immune microenvironment during childhood development and the heightened risk of complications from long-term use of immunosuppressive drugs. The overwhelming majority of children may require more than one kidney transplant in their lifetime. Acute rejection (AR) stands as the primary cause of kidney transplant failure in children. While pathologic biopsy remains the "gold standard" for diagnosing renal rejection, its invasive nature raises concerns regarding potential functional impairment and the psychological impact on children due to repeated procedures. In this review, we outline the current research status of novel biomarkers associated with AR in urine and blood after pediatric kidney transplantation. These biomarkers exhibit superior diagnostic and prognostic performance compared to conventional ones, with the added advantages of being less invasive and highly reproducible for long-term graft monitoring. We also integrate the limitations of these novel biomarkers and propose a refined monitoring model to optimize the management of AR in pediatric kidney transplantation.

Supramolecular prodrug-like nanotheranostics with dynamic and activatable nature for synergistic photothermal immunotherapy of metastatic cancer

Synergistic photothermal immunotherapy has attracted widespread attention due to the mutually reinforcing therapeutic effects on primary and metastatic tumors. However, the lack of clinical approval nanomedicines for spatial, temporal, and dosage control of drug co-administration underscores the challenges facing this field. Here, a photothermal agent (Cy7-TCF) and an immune checkpoint blocker (NLG919) are conjugated via disulfide bond to construct a tumor-specific small molecule prodrug (Cy7-TCF-SS-NLG), which self-assembles into prodrug-like nano-assemblies (PNAs) that are self-delivering and self-formulating. In tumor cells, over-produced GSH cleaves disulfide bonds to release Cy7-TCF-OH, which re-assembles into nanoparticles to enhance photothermal conversion while generate reactive oxygen species (ROSs) upon laser irradiation, and then binds to endogenous albumin to activate near-infrared fluorescence, enabling multimodal imaging-guided phototherapy for primary tumor ablation and subsequent release of tumor-associated antigens (TAAs). These TAAs, in combination with the co-released NLG919, effectively activated effector T cells and suppressed Tregs, thereby boosting antitumor immunity to prevent tumor metastasis. This work provides a simple yet effective strategy that integrates the supramolecular dynamics and reversibility with stimuli-responsive covalent bonding to design a simple small molecule with synergistic multimodal imaging-guided phototherapy and immunotherapy cascades for cancer treatment with high clinical value.