Emerging targets for cancer treatment: S100A9/RAGE

Pathological role of RAGE underlying progression of various diseases: its potential as biomarker and therapeutic target

The receptor for advanced glycation end products (RAGE) is a multi-ligand receptor with several structural types, performing a myriad of molecular mechanisms. The RAGE-ligand interactions play important roles in maintaining latent chronic inflammation, and oxidative damage underlying various pathological conditions like metabolic syndrome (MetS), neurodegenerative diseases, stroke, cardiovascular disorders, pulmonary disorders, cancer and infections. RAGE is thoroughly explored in knockout animals and human trials, targeted by small molecule inhibitors, peptides, diet, and natural compounds. But it is yet to be incorporated in the mainstream management of any ailment. This review performs an appraisal of the pathological mechanisms influenced by RAGE to uncover its prospects as a biomarker while also assessing its power to become a promising therapeutic target.

Targeting Cancer With Bifunctional Peptides: Mechanism of Cell Entry and Inciting Cell Death

Antimicrobial peptides have gained much attention in clinical research due to their extensive possibilities of application beyond antimicrobial use. The modification of antimicrobial peptides enables the peptides to target particular cancer cells, improving the specificity and efficiency of the treatment. In this study, TP2-D-Tox, a derivative of TP-D-Tox, demonstrated a superior anti-tumor activity towards renal carcinoma, Caki-2, and breast carcinoma, SK-BR-3. TP-Tox was previously reported to inhibit tumor growth in a mouse model, increasing the overall survival. TP- and TP2-D-Tox were shown to penetrate the cells via clathrin-mediated endocytosis, triggered by binding to the subunits of non-muscle myosin IIa and S100A9. HSPB1 was observed to have a protective effect towards TP2-D-Tox against the immediate proteolytic inactivation. The intracellular presence of the peptides evoked mitochondrial permeability transition, generation of reactive oxygen species, and formation of MLKL oligomers in the plasma membrane. Our investigation revealed that TP- and TP2-D-Tox induced a similar but distinctly regulated cell death in Caki-2 and SK-BR-3 cells. Both peptides established toxicity without activating any caspases, suggesting the possibility of TP- and TP2-D-Tox as a promising approach to bypass the caspase-dependent apoptosis-resistance issue impairing therapeutic responses of many cancer treatments.

Potential of ex vivo organotypic slice cultures in neuro-oncology

Over recent decades, in vitro and in vivo models have significantly advanced brain cancer research; however, each presents distinct challenges for accurately mimicking in situ conditions. In response, organotypic slice cultures have emerged as a promising model recapitulating precisely specific in vivo phenotypes through an ex vivo approach. Ex vivo organotypic brain slice models can integrate biological relevance and patient-specific variability early in drug discovery, thereby aiming for more precise treatment stratification. However, the challenges of obtaining representative fresh brain tissue, ensuring reproducibility, and maintaining essential central nervous system (CNS)-specific conditions reflecting the in situ situation over time have limited the direct application of ex vivo organotypic slice cultures in robust clinical trials. In this review, we explore the benefits and possible limitations of ex vivo organotypic brain slice cultures in neuro-oncological research. Additionally, we share insights from clinical experts in neuro-oncology on how to overcome these current limitations and improve the practical application of organotypic brain slice cultures beyond academic research.

Pyroptosis-related genes features on prediction of the prognosis in liver cancer: An integrated analysis of bulk and single-cell RNA sequencing

Objective

This study explores the impact of pyroptosis-related genes (PRG) on the prognosis of liver cancer (LC).

Methods

421 samples (371 tumor samples and 50 normal samples) from the Cancer Genome Atlas (TCGA) were included in this study. GSE14520 dataset (data of RNA expression and relevant clinicopathological features), GSE125449 dataset (single-cell data in LC) and HCCDB18 dataset (validation on the reliability of the model) were downloaded as appropriate. Download the PRG and its corresponding pathway information from the gene set enrichment analysis (GSEA) website. The consensus clustering was performed by ConsensusClusterPlus package. Differentially expressed genes (DEGs) were identified using limma package, and prognostic features were constructed using un/multivariate and Lasso Cox regression. Pathway enrichment analysis was conducted by ssGSEA method. Receiver Operating Characteristic and the survival analysis were conducted by timeROC and Survminer packages. The Seurat package was used for single-cell RNA sequencing (scRNA-seq) analysis. For cellular validation, following the quantification on the key genes via reverse-transcription quantitative PCR, the Transwell and scratch assays were applied to evaluate the in-vitro invasion and migration of LC cells Huh-7.

Results

12 prognosis-related genes were identified to be related to the progression of LC. Three subtypes including C1, C2 and C3 were categorized using the 12 prognosis-related genes and PRGs significantly related to the prognosis of LC patients. The worst and best prognosis was seen in C3 subtype and C2 subtype, respectively. Hallmark pathway enrichment analysis has shown the concurrent immunoactivation and immune escape in C3 subtype. A RiskScore model was constructed using 8 key genes (KPNA2, UCK2, FTCD, CBX2, RAB32, HMMR, S100A9 and ANXA10) from the DEGs of three subtypes. The RiskScore system as an independent prognostic factor dividing the patients into high and low risk groups, and patients of the high-risk group had poor prognosis in both test set and validation set. A nomogram model combining the risk score had the extreme higher benefit. Further, 6 subclusters were identified from scRNA-seq analysis, where the highest PYROPTOSIS score was seen in Monocytic-Macrophages. The quantification on the key genes has suggested the high expressions of KPNA2, UCK2, CBX2, RAB32, HMMR and S100A9 and the low expressions of FTCD and ANXA10 in LC cells Huh-7. Particularly, UCK2 knockdown evidently diminished the number of invaded and migrated LC cells in vitro.

Conclusion

The risk model associated with pyproptosis is crucial for the tumor immunity of LC and may serve as a prognostic indicator for patients suffering from LC. Our findings will offer new perspectives for immunotherapies targeting LC.

Leptomeningeal metastases from solid tumors: A Society for Neuro-Oncology and American Society of Clinical Oncology consensus review on clinical management and future directions

Leptomeningeal metastases (LM) are increasingly becoming recognized as a treatable, yet generally incurable, complication of advanced cancer. As modern cancer therapeutics have prolonged the lives of patients with metastatic cancer, specifically in patients with parenchymal brain metastases, treatment options, and clinical research protocols for patients with LM from solid tumors have similarly evolved to improve survival within specific populations. Recent expansions in clinical investigation, early diagnosis, and drug development have given rise to new unanswered questions. These include leptomeningeal metastasis biology and preferred animal modeling, epidemiology in the modern cancer population, ensuring validation and accessibility of newer leptomeningeal metastasis diagnostics, best clinical practices with multimodality treatment options, clinical trial design and standardization of response assessments, and avenues worthy of further research. An international group of multi-disciplinary experts in the research and management of LM, supported by the Society for Neuro-Oncology and American Society of Clinical Oncology, were assembled to reach a consensus opinion on these pressing topics and provide a roadmap for future directions. Our hope is that these recommendations will accelerate collaboration and progress in the field of LM and serve as a platform for further discussion and patient advocacy.

S100A9, as a potential predictor of prognosis and immunotherapy response for GBM, promotes the malignant progression of GBM cells and migration of M2 macrophages

In the past decades, the therapeutic effect of glioblastoma (GBM) has not been significantly improved. Generous evidence indicates that S100A9 has a wide range of functions in tumors, but its exploration in GBM is less. The purpose of this study is to conduct a comprehensive bioinformatics analysis and cytological experiment on S100A9 in GBM. The expression data and clinical data of GBM samples were downloaded from the public database, and comprehensive bioinformatics analysis was performed on S100A9 in GBM using R software. Wound healing assay and transwell assay were used to detect the migration activity of cells, and colony formation assay, EdU staining, and CCK-8 assay were used to detect the proliferation activity of cells. The effect of S100A9 on the migration activity of M2 macrophages was verified by the cell co-culture method. The protein expression was detected by western blotting and immunohistochemical staining. S100A9 is an independent prognostic factor in GBM patients and is related to poor prognosis. It can be used as an effective tool to predict the response of GBM patients to immune checkpoint inhibitors (ICIs). In addition, S100A9 can promote the malignant progression of GBM and the migration of M2 macrophages. On the whole, our study highlights the potential value of S100A9 in predicting prognosis and immunotherapeutic response in GBM patients. More importantly, S100A9 may promote the malignant progress of GBM by involving in some carcinogenic pathways and remodeling the tumor microenvironment (TME).

Single-cell transcriptomics reveals the aggressive landscape of high-grade serous carcinoma and therapeutic targets in tumor microenvironment

High-grade serous carcinoma (HGSC) is characterized by early abdominal metastasis, leading to a dismal prognosis. In this study, we conducted single-cell RNA sequencing on 109,573 cells from 34 tumor samples of 18 HGSC patients, including both primary tumors and their metastatic sites. Our analysis revealed a distinct S100A9+ tumor cell subtype present in both primary and metastatic sites, strongly associated with poor overall survival. This subtype exhibited high expression of S100A8, S100A9, ADGRF1, CEACAM6, CST6, NDRG2, MUC4, PI3, SDC1, and C15orf48. Individual knockdown of these ten marker genes, validated through in vitro and in vivo models, significantly inhibited ovarian cancer growth and invasion. Around S100A9+ tumor cells, a population of HK2+_CAF was identified, characterized by activated glycolysis metabolism, correlating with shorter overall survival in patients. Notably, similar to CAFs, immunosuppressive tumor-associated macrophage (TAM) subtypes underwent glycolipid metabolism reprogramming via PPARgamma regulation, promoting tumor metastasis. These findings shed light on the mechanisms driving the aggressiveness of HGSC, offering crucial insights for the development of novel therapeutic targets against this formidable cancer.

Single-cell atlas reveals the immunosuppressive microenvironment and Treg cells landscapes in recurrent Glioblastoma

Patients diagnosed with glioblastoma (GBM) have the most aggressive tumor progression and lethal recurrence. Research on the immune microenvironment landscape of tumor and cerebrospinal fluid (CSF) is limited. At the single-cell level, we aim to reveal the recurrent immune microenvironment of GBM and the potential CSF biomarkers and compare tumor locations. We collected four clinical samples from two patients: malignant samples from one recurrent GBM patient and non-malignant samples from a patient with brain tumor. We performed single-cell RNA sequencing (scRNA-seq) to reveal the immune landscape of recurrent GBM and CSF. T cells were enriched in the malignant tumors, while Treg cells were predominately found in malignant CSF, which indicated an inhibitory microenvironment in recurrent GBM. Moreover, macrophages and neutrophils were significantly enriched in malignant CSF. This indicates that they an important role in GBM progression. S100A9, extensively expressed in malignant CSF, is a promising biomarker for GBM diagnosis and recurrence. Our study reveals GBM's recurrent immune microenvironment after chemoradiotherapy and compares malignant and non-malignant CSF samples. We provide novel targets and confirm the promise of liquid CSF biopsy for patients with GBM.

Nε-(1-Carboxymethyl)-L-lysine/RAGE Signaling Drives Metastasis and Cancer Stemness through ERK/NFκB axis in Osteosarcoma

Osteosarcoma is an extremely aggressive bone cancer with poor prognosis. Nε-(1-Carboxymethyl)-L-lysine (CML), an advanced glycation end product (AGE), can link to cancer progression, tumorigenesis and metastasis, although the underlying mechanism remains unclear. The role of CML in osteosarcoma progression is still unclear. We hypothesized that CML could promote migration, invasion, and stemness in osteosarcoma cells. CML and its receptor (RAGE; receptor for AGE) were higher expressed at advanced stages in human osteosarcoma tissues. In mouse models, which streptozotocin was administered to induce CML accumulation in the body, the subcutaneous tumor growth was not affected, but the tumor metastasis using tail vein injection model was enhanced. In cell models (MG63 and U2OS cells), CML enhanced tumor sphere formation and acquisition of cancer stem cell characteristics, induced migration and invasion abilities, as well as triggered the epithelial-mesenchymal transition process, which were associated with RAGE expression and activation of downstream signaling pathways, especially the ERK/NFκB pathway. RAGE inhibition elicited CML-induced cell migration, invasion, and stemness through RAGE-mediated ERK/NFκB pathway. These results revealed a crucial role for CML in driving stemness and metastasis in osteosarcoma. These findings uncover a potential CML/RAGE connection and mechanism to osteosarcoma progression and set the stage for further investigation.

Updating cancer research with patient-focused networks

Multidisciplinary patient-centered networks offer access to difficult-to-get samples and initiate projects from human material. Improving such networks to include 'living' samples could be transformative, not only for research but for clinical trial design, especially when focused on unmet clinical needs, such as brain metastasis.

Targeting S100A9 protein affects mTOR-ER stress signaling and increases venetoclax sensitivity in Acute Myeloid Leukemia

Acute Myeloid Leukemia (AML) is a heterogeneous disease with limited treatment options and a high demand for novel targeted therapies. Since myeloid-related protein S100A9 is abundantly expressed in AML, we aimed to unravel the therapeutic impact and underlying mechanisms of targeting both intracellular and extracellular S100A9 protein in AML cell lines and primary patient samples. S100A9 silencing in AML cell lines resulted in increased apoptosis and reduced AML cell viability and proliferation. These therapeutic effects were associated with a decrease in mTOR and endoplasmic reticulum stress signaling. Comparable results on AML cell proliferation and mTOR signaling could be observed using the clinically available S100A9 inhibitor tasquinimod. Interestingly, while siRNA-mediated targeting of S100A9 affected both extracellular acidification and mitochondrial metabolism, tasquinimod only affected the mitochondrial function of AML cells. Finally, we found that S100A9-targeting approaches could significantly increase venetoclax sensitivity in AML cells, which was associated with a downregulation of BCL-2 and c-MYC in the combination group compared to single agent therapy. This study identifies S100A9 as a novel molecular target to treat AML and supports the therapeutic evaluation of tasquinimod in venetoclax-based regimens for AML patients.

Diabetes Mellitus Is a Strong Independent Negative Prognostic Factor in Patients with Brain Metastases Treated with Radiotherapy

BACKGROUND

Brain metastases (BM) cause relevant morbidity and mortality in cancer patients. The presence of cerebrovascular diseases can alter the tumor microenvironment, cellular proliferation and treatment resistance. However, it is largely unknown if the presence of distinct cerebrovascular risk factors may alter the prognosis of patients with BM.

METHODS

Patients admitted for the radiotherapy of BM at a large tertiary cancer center were included. Patient and survival data, including cerebrovascular risk factors (diabetes mellitus (DM), smoking, arterial hypertension, peripheral arterial occlusive disease, hypercholesterolemia and smoking) were recorded.

RESULTS

203 patients were included. Patients with DM (n = 39) had significantly shorter overall survival (OS) (HR 1.75 (1.20-2.56), p = 0.003, log-rank). Other vascular comorbidities were not associated with differences in OS. DM remained prognostically significant in the multivariate Cox regression including established prognostic factors (HR 1.92 (1.20-3.06), p = 0.006). Furthermore, subgroup analyses revealed a prognostic role of DM in patients with non-small cell lung cancer, both in univariate (HR 1.68 (0.97-2.93), p = 0.066) and multivariate analysis (HR 2.73 (1.33-5.63), p = 0.006), and a trend in melanoma patients.

CONCLUSION

DM is associated with reduced survival in patients with BM. Further research is necessary to better understand the molecular mechanisms and therapeutic implications of this important interaction.