Xuezhen Zeng

The liver microenvironment is essential to immune surveillance and liver cancer progression. Here, the aim is to identify the role of METTL5, the 18S rRNA m ⁶ A methyltransferase, in regulating the liver immune microenvironment to promote cancer progression. Liver‐specific Mettl5 knockout (cKO) in mice exhibits increased immune cell infiltration, especially CD3 ⁺ and CD4 ⁺ T cells. Loss of Mettl5 inhibits intrahepatic cholangiocarcinoma (ICC) progression. By scRNA‐seq analysis, it is found that ICC from both cKO mice and human METTL5 low expression group correlates with increased CD8 ⁺ T cells but decreased macrophages, which is associated with better survival. Adoptive transfer of macrophages significantly promotes ICC progression. scRNA‐seq and scTCR‐seq analysis show that cKO mice exhibit reduced immunosuppressive Ms4a7 ⁺ C1qa ⁺ tumor‐associated macrophages (TAMs) but increased intratumoral IFN‐γ ⁺ CD8 ⁺ T cell infiltration and expansion. Mechanistically, METTL5‐mediated 18S rRNA m ⁶ A modification downregulates the mRNA translation of CXCL16 to exclude CD8 ⁺ T cells. Knockout of Mettl5 significantly increases CD8 ⁺ T cell infiltration in vivo. Combined METTL5 targeting using lipid nanoparticle‐encapsulated siRNA and PD‐1 blockade provokes anti‐tumor immunity to eradicate ICC tumors. Additionally, METTL5 ^Low human ICC correlates with responsiveness to immunotherapy. The study highlights the strong immuno‐evasive ability of METTL5 as a promising therapeutic target in ICC.

Radiofrequency ablation (RFA) is the first-line treatment for early-stage hepatocellular carcinoma (HCC). However, recurrence after curative RFA remains a significant challenge for HCC patients. Although RFA induces an immune response, the anti-tumor effect is often limited by the immunosuppressive tumor microenvironment. Enhancing anti-tumor immunity is essential to improve treatment efficacy and prevent recurrence. In this study, we explore the efficacy and underlying mechanisms of the combination of RFA and anti-PD-1 in suppressing abscopal and recurrent tumors. We established a bilateral subcutaneous HCC mouse model and performed complete RFA on the right-flank tumor. Anti-PD-1 or anti-IgG was administered post-RFA. Tumor growth, immune cell profiles, and molecular pathways were assessed using flow cytometry, immunohistochemistry staining, RNA-sequencing, and Western blot. Chemokines released by the tumor were detected by ELISA. An in vivo tumor rechallenge experiment was performed after a complete tumor regression to evaluate the immune memory induced by the RFA+anti-PD-1 treatment. RFA combined with anti-PD-1 significantly suppressed abscopal tumor growth and prolonged survival. Compared with RFA monotherapy, the infiltration of CD8⁺T cells and dendritic cells was significantly increased in the combined treatment group, while PMN-MDSCs were markedly reduced. Mechanistically, the chemokine signaling pathway and JAK-STAT signaling pathway were activated in the tumor of the RFA+anti-PD-1 group with upregulation of CXCL10 to recruit CD8⁺T cells. In addition, the combination therapy induced durable immune memory that inhibited rechallenge tumor outgrowth. Our study discovered that RFA combined with anti-PD-1 induced anti-tumor immunity to inhibit abscopal tumors and durable immune memory to prevent recurrence, suggesting RFA+anti-PD-1 as a potential therapeutic strategy for multifocal HCC and preventing recurrence.

Background: Necroptosis, a recently identified mechanism of programmed cell death, exerts significant influence on various aspects of cancer biology, including tumor cell proliferation, stemness, metastasis, and immunosuppression. However, the role of necroptosis-related genes (NRGs) in Hepatocellular Carcinoma (HCC) remains elusive. Methods: In this study, we assessed the mutation signature, copy number variation, and expression of 37 NRGs in HCC using the TCGA-LIHC dataset. We further validated our results using the ICGC-LIRI-JP dataset. To construct our prognostic model, we utilized the least absolute shrinkage and selection operator (LASSO), and evaluated the predictive efficacy of the NRGs-score using various machine learning algorithms, including K-M curves, time-ROC curves, univariate and multivariate Cox regression, and nomogram. In addition, we analyzed immune infiltration using the CIBERSOFT and ssGSEA algorithms, calculated the stemness index through the one-class logistic regression (OCLR) algorithm, and performed anti-cancer stem cells (CSCs) drug sensitivity analysis using oncoPredict. Finally, we validated the expression of the prognostic NRGs through qPCR both in vitro and in vivo. Results: About 18 out of 37 NRGs were found to be differentially expressed in HCC and correlated with clinical outcomes. To construct a prognostic model, six signature genes (ALDH2, EZH2, PGAM5, PLK1, SQSTM1, and TARDBP) were selected using LASSO analysis. These genes were then employed to categorize HCC patients into two subgroups based on NRGs-score (low vs. high). A high NRGs score was associated with a worse prognosis. Furthermore, univariate and multivariate Cox regression analyses were performed to confirm the NRGs-score as an independent risk factor. These analyses revealed strong associations between NRGs-score and critical factors, such as AFP, disease stage, and tumor grade in the HCC cohort. NRGs-score effectively predicted the 1-, 3-, and 5-year survival of HCC patients. Immune infiltration analysis further revealed that the expression of immune checkpoint molecules was significantly enhanced in the high NRGs-score group. Stemness analysis in the HCC cohort showed that NRGs-score was positively correlated with mRNA stemness index, and patients with high NRGs-score were sensitive to CSCs inhibitors. The findings from the external validation cohort provided confirmation that the NRGs-score presented a trait with universal applicability in accurately predicting the survival of HCC. Additionally, the six prognostic genes were consistently differentially expressed in both the HCC cell line and the mouse HCC model. Conclusions: Our study demonstrated the pivotal role of NRGs in promoting stemness and immune suppression in HCC and established a robust model which could successfully predict HCC prognosis.

Introduction: Schizophrenia (SCZ) is a severe psychiatric disorder whose pathophysiology remains elusive. Recent investigations have underscored the significance of systemic inflammation, particularly the impact of circulating inflammatory proteins, in SCZ.Methods: This study explores the potential causal association between certain inflammatory proteins and SCZ. Bidirectional Mendelian randomization (MR) analyses were conducted utilizing data from expansive genome-wide association studies (GWAS). Data regarding circulating inflammatory proteins were sourced from the GWAS Catalog database, encompassing 91 inflammatory cytokines. SCZ-related data were derived from the Finngen database, incorporating 47,696 cases and 359,290 controls. Analytical methods such as inverse variance weighted, MR-Egger, weighted median, simple mode, and weighted mode were employed to evaluate the association between inflammatory cytokines and SCZ. Sensitivity analyses were also performed to affirm the robustness of the results.Results: Following FDR adjustment, significant associations were observed between levels of inflammatory cytokines, including Fibroblast Growth Factor 5 (OR = 1.140, 95%CI = 1.045, 1.243, p = 0.003, FDR=0.015), C-C Motif Chemokine 4 (OR = 0.888, 95%CI = 0.816, 0.967, p = 0.006, FDR = 0.015), C-X-C Motif Chemokine 1 (OR = 0.833, 95%CI = 0.721, 0.962, p = 0.013, FDR = 0.064), and C-X-C Motif Chemokine 5 (OR = 0.870, 95%CI = 0.778, 0.973, p = 0.015, FDR = 0.074), and the risk of SCZ.Conclusion: Our results from MR analysis suggest a potential causal link between circulating inflammatory cytokines and SCZ, thereby enriching our understanding of the interactions between inflammation and SCZ. Furthermore, these insights provide a valuable foundation for devising therapeutic strategies targeting inflammation.

Background: Cuproptosis is a newly discovered form of programmed cell death, which is characterized by accumulation of intra-cellular copper ion leading to the aggregation of lipoproteins and destabilization of Fe-S cluster proteins in mitochondrial metabolism, thereby affecting the prognosis of patients with cancer. However, the role of cuproptosis-related genes (CRGs) in hepatocellular carcinoma (HCC) remains elusive.Methods: Mutation signature, copy number variation and the expression of 10 CRGs were assessed in HCC from TCGA-LIHC dataset. ICGC-LIRI-JP dataset was used as further validation cohort. The least absolute shrinkage and selection operator (LASSO) was used to construct the prognostic model. Kaplan Meier curves, time-ROC curves, nomogram, univariate and multivariate Cox regression were utilized to evaluate the predictive efficacy of CRGs-score. Immune infiltration was analyzed by CIBERSOFT, ssGSEA algorithm, and TIMER database. The expression of prognostic CRGs was validated by qPCR both in-vitro and in-vivo. Drug sensitivity analysis was performed by pRRophetic.Results: All of the CRGs were differentially expressed in HCC and 5 out of them (CDKN2A, DLAT, GLS, LIPT1, MTF1) correlated with patient survival. These signature genes were selected by LASSO analysis to establish a prognosis model to stratify HCC patients into high and low CRGs-score subgroups. High CRGs-score was associated with a worse prognosis. Subsequently, univariate and multivariate Cox regression verified that CRGs-score was an independent cancer risk factor that correlated with clinical factors including stage and grade. Nomogram integrating the CRGs-score and clinical risk factors performed well to predict patient survival. Immune infiltration analysis further revealed that the expression of immune checkpoint genes was significantly enhanced in high CRGs-score group, especially PD-1 and PD-L1. An independent validation cohort (ICGC) confirmed that CRGs-score as a stable and universally applicable indicator in predicting HCC patient survival. Concordantly, the expression of five confirmed signature genes were also differentially expressed in human HCC cell lines and mouse HCC model. In addition, we also analyzed the sensitivity of 10 clinical targeted therapies between high and low CRGs-score groups.Conclusion: This study elucidated the role of dysregulated CRGs in HCC cohort, with validation with in-vitro and in-vivo models. The CRGs-score might be applied as a novel prognostic factor in HCC.

A drastic difference exists between the 5-year survival rates of colorectal cancer patients with localized cancer and distal organ metastasis. The liver is the most favorable organ for cancer metastases from the colorectum. Beyond the liver-colon anatomic relationship, emerging evidence highlights the impact of liver immune microenvironment on colorectal liver metastasis. Prior to cancer cell dissemination, hepatocytes secrete multiple factors to recruit or activate immune cells and stromal cells in the liver to form a favorable premetastatic niche. The liver-resident cells including Kupffer cells, hepatic stellate cells, and liver-sinusoidal endothelial cells are co-opted by the recruited cells, such as myeloid-derived suppressor cells and tumor-associated macrophages, to establish an immunosuppressive liver microenvironment suitable for tumor cell colonization and outgrowth. Current treatments including radical surgery, systemic therapy, and localized therapy have only achieved good clinical outcomes in a minority of colorectal cancer patients with liver metastasis, which is further hampered by high recurrence rate. Better understanding of the mechanisms governing the metastasis-prone liver immune microenvironment should open new immuno-oncology avenues for liver metastasis intervention.