ALOX5 acts as a key role in regulating the immune microenvironment in intrahepatic cholangiocarcinoma, recruiting tumor-associated macrophages through PI3K pathway

Lipid Metabolism Reprogramming in Tumor-Associated Macrophages Modulates Their Function in Primary Liver Cancers

Lipids are a complex class of biomolecules with pivotal roles in the onset, progression, and maintenance of cancers. Lipids, derived from the tumor microenvironment (TME) or synthesized by cancer cells themselves, govern a large variety of pro-tumorigenic functions. In recent years, lipid metabolism and the reprogramming of liver cancer cells have received increasing attention, revealing that altered regulation of diverse lipid species, including triacylglycerols, phospholipids, sphingolipids, ceramides, fatty acids, and cholesterol, actively contributes to the initiation and progression of primary liver cancer. Lipid metabolic reprogramming also modifies the TME by influencing the recruitment, activation, and function of immune cells. Tumor-associated macrophages (TAM) are essential components of TME that sustain cancer growth, promoting invasion and mediating immune evasion. Macrophage polarization toward a tumor-supportive phenotype is associated with metabolic reprogramming. Indeed, lipid accumulation and enhanced fatty acid oxidation in TAM contribute to polarization to a M2 phenotype. In this review, we examine lipid metabolism in hepatocellular carcinoma and cholangiocarcinoma, focusing on TAM lipid metabolic reprogramming.

External validation of plasma CSF1 as a preoperative prognostic marker in patients with resectable intrahepatic cholangiocarcinoma

INTRODUCTION

Long-term prognosis after resection for intrahepatic cholangiocarcinoma (iCCA) remains poor and the preoperative oncological risk assessment is difficult. Two immune system-related plasma proteins, colony stimulating factor 1 (CSF1) and TNF-related apoptosis-inducing ligand (TRAIL), were previously indicated as prognostic factors in iCCA. This study aimed to externally validate CSF1 and TRAIL as preoperative prognostic markers for patients with resectable iCCA.

MATERIALS AND METHODS

Preoperative plasma CSF1 and TRAIL concentrations (pg/mL) were determined from prospectively collected biobank samples by multiplex immunoanalysis, for patients with resectable iCCA operated at two tertiary referral centers. Primary outcome was overall survival (OS), analyzed by Kaplan-Meier method and Cox regression. Secondary outcome was disease-free survival (DFS). Discrimination was evaluated with concordance indices (C-index) and prognostic performance assessed with calibration curves.

RESULTS

Sixty-one patients with resection for iCCA were included. CSF1 was associated with both OS (hazard ratio [HR] 1.03, 95 % confidence interval [CI] 1.01-1.05) and DFS (HR 1.02, 95 % CI 1.00-1.04). Median OS was eight months for patients with CSF1 levels in the upper quartile (≥158 pg/mL), compared to the overall median OS of 47 months. While TRAIL was not significantly associated with OS (P = 0.216), levels in the lower quartile (≤256 pg/mL) were associated with short DFS (P = 0.004). The C-index of CSF1 for OS was 0.70, with excellent calibration for three- and five-year OS.

CONCLUSIONS

Preoperative plasma CSF1 was validated as a novel, well-calibrated predictor of poor survival in resectable iCCA, which could assist the preoperative risk assessment. Low plasma TRAIL was associated with early recurrence.

Immunomodulatory effects of traditional chinese medicine on cancer: insights from network pharmacology and single-cell RNA sequencing data on the treatment of lung adenocarcinoma with shenling baizhu powder

Shenling Baizhu Powder (SLBZP), commonly used as a complementary and alternative therapy for lung adenocarcinoma (LUAD), is believed to enhance patients' immune function. However, its underlying mechanisms remain unclear. By integrating network pharmacology and single-cell RNA sequencing (scRNA-seq) data, the study investigates the immune therapeutic effects of SLBZP in LUAD. Immune infiltration landscape analysis revealed significant differences in immune cell infiltration levels between normal and LUAD groups. ScRNA-seq analysis showed that LUAD progression was associated with an increased abundance of macrophage infiltration, and the characteristics of 13 macrophage clusters were closely related to target genes. Using machine learning, we identified 4 macrophage-related gene sets associated with LUAD: ALOX5, IL2RA, MMP9, and PPARG. Immune infiltration analysis demonstrated a strong correlation between these target genes and immune responses. Molecular docking results indicated that SLBZP could modulate these target genes through various bioactive compounds, indirectly affecting macrophages to enhance the immune system's functional state. This study provides new insights into the role of tonifying TCM formulas in tumor immune modulation and offers theoretical support for future clinical research.

Tumor-associated macrophages: orchestrators of cholangiocarcinoma progression

Cholangiocarcinoma (CCA) is a rare but highly invasive cancer, with its incidence rising in recent years. Currently, surgery remains the most definitive therapeutic option for CCA. However, similar to other malignancies, most CCA patients are not eligible for surgical intervention at the time of diagnosis. The chemotherapeutic regimen of gemcitabine combined with cisplatin is the standard treatment for advanced CCA, but its effectiveness is often hampered by therapeutic resistance. Recent research highlights the remarkable plasticity of tumor-associated macrophages (TAMs) within the tumor microenvironment (TME). TAMs play a crucial dual role in either promoting or suppressing tumor development, depending on the factors that polarize them toward pro-tumorigenic or anti-tumorigenic phenotypes, as well as their interactions with cancer cells and other stromal components. In this review, we critically examine recent studies on TAMs in CCA, detailing the expression patterns and prognostic significance of different TAM subtypes in CCA, the mechanisms by which TAMs influence CCA progression and immune evasion, and the potential for reprogramming TAMs to enhance anticancer therapies. This review aims to provide a framework for deeper future research.

ALOX5 drives the pyroptosis of CD4+ T cells and tissue inflammation in rheumatoid arthritis

Pyroptosis, an inflammatory form of programmed cell death, is linked to the pathology of rheumatoid arthritis (RA). Here, we investigated the molecular mechanism underlying pyroptosis in T cells isolated from patients with RA. Compared with healthy individuals, patients with RA had more pyroptotic CD4+ T cells in blood and synovia, which correlated with clinical measures of disease activity. Moreover, the mRNA expression and protein abundance of arachidonate 5-lipoxygenase (ALOX5), which converts arachidonic acid to leukotriene A4 (LTA4), were increased in CD4+ T cells from patients with RA and, among patients with RA, were lowest in those in clinical remission. Knockdown or pharmacological inhibition of ALOX5 suppressed CD4+ T cell pyroptosis and improved symptoms in two rodent models of RA. Mechanistically, the increase in ALOX5 activity in RA CD4+ T cells enhanced the production of the LTA4 derivative LTB4, which stimulated Ca2+ influx through ORAI3 channels, leading to the activation of NLRP3 inflammasomes and pyroptosis. Our findings reveal a role for ALOX5 in RA and provide a molecular basis for further exploring the clinical utility of ALOX5 inhibition in RA and for using ALOX5 as a biomarker to distinguish active disease and remission in RA.