Neutrophils, constituting 50-70 % of circulating leukocytes, serve as first responders in innate immunity. In recent years, as research into the tumor immune microenvironment has intensified, the role of neutrophils in tumor has gained increasing attention. Studies have shown that neutrophils are involved in tumor growth, metastasis, angiogenesis, and immune regulation. However, because tumor-associated neutrophils (TANs) often exhibit dual-edged effects and significant heterogeneity, it remains challenging to determine whether they act as allies or adversaries. This review systematically summarizes the classification and functions of neutrophils in tumor. Additionally, the current challenges in tumor-associated neutrophils are discussed, aiming to provide new insights for the development of neutrophil-related immunotherapies.

Pathological images of hepatocellular carcinoma (HCC) contain abundant tumor information that can be used to stratify patients. However, the links between histology images and the treatment response have not been fully unveiled. We trained and evaluated a model by predicting the prognosis of 287 non-treated HCC patients postoperatively, and further explored the model’s treatment response predictive ability in 79 sorafenib-treated patients. Based on prognostic relevant pathological signatures (PPS) extracted from CNN-SASM, which was trained by denoised recurrence label (DRL) under different thresholds, the PPS-based prognostic model was formulated. A total of 78 HCC patients from TCGA-LIHC were used for the external validation. We proposed the CNN-SASM based on tumor pathology and extracted PPS. Survival analysis revealed that the PPS-based prognostic model yielded the AUROC of 0.818 and 0.811 for predicting recurrence at 1 and 2 years after surgery, with an external validation reaching 0.713 and 0.707. Furthermore, the predictive ability of the PPS-based prognostic model was superior to clinical risk indicators, and it could stratify patients with significantly different prognoses. Importantly, our model can also stratify sorafenib-treated patients into two groups associated with significantly different survival situations, which could effectively predict survival benefits from sorafenib. Our prognostic model based on pathology deep learning provided a valuable means for predicting HCC patient recurrence condition, and it could also improve patient stratification to sorafenib treatment, which help clinical decision-making in HCC.

SLFN11, a member of the evolutionarily conserved SLFN gene family, is an interferon-stimulated early response gene. This review comprehensively explores its multifaceted roles. Structurally, its three distinct domains endow it with diverse functions. Epigenetic modifications, post-translational alterations, and multiple signaling pathways intricately regulate SLFN11 expression and activity. In terms of functions, it plays crucial roles in the DNA damage response during replication stress, distinct from traditional pathways. It also serves as a protector in the antiviral response and a valuable biomarker for predicting the efficacy of DNA-damaging agents and patient prognosis in various cancers. Beyond these, SLFN11 has non-canonical functions, including immune regulation, modulation of oncological behaviors, involvement in apoptosis, protection against proteotoxic stress, and association with Fanconi anemia. Looking ahead, SLFN11 holds great promise as a biomarker for personalized medicine, but challenges like developing accurate detection methods remain. In immunotherapy, understanding its dynamic changes is essential for optimizing treatment. Strategies to overcome SLFN11-low expression, such as epigenetic modulation, also need further investigation, which may open new avenues for disease treatment.

Histopathological evaluation is a cornerstone of cancer identification but often involves time-consuming labeling processes (∼days per sample) and experience-dependent interpretation. Herein, we introduce a rapid (∼40 min per sample) and label-free histopathological method based on metabolic fingerprinting of tissue using nanoparticle-enhanced laser desorption/ionization mass spectrometry. Applied to gastric cancer (GC, n = 284 paired tissue), this approach distinguishes malignant from benign tissues (area under the curve [AUC] of 0.979), identifies tumor subtypes (AUC of 0.963), and assesses prognosis (p < 0.05) without specialized pathologists. External validation on 238 samples from an independent cohort confirmed its robustness. This method advances histopathological analysis, offering potential for scalable clinical use.

Lecithin cholesterol acyltransferase (LCAT), a crucial enzyme in lipid metabolism, plays important yet poorly understood roles in tumours, especially in hepatocellular carcinoma (HCC). In this study, our investigation revealed that LCAT is a key downregulated metabolic gene and an independent risk factor for poor prognosis in patients with HCC. Functional experiments showed that LCAT inhibited HCC cell proliferation, migration and invasion. Mechanistically, LCAT interacts with caveolin-1 (CAV1) to promote the binding of CAV1 to PRKACA and inhibit its phosphorylation, thereby inhibiting triglyceride (TAG) catabolism. On the other hand, LCAT inhibits fatty acid oxidation (FAO) by interacting with CPT1A to promote its ubiquitination and degradation. These events result in an inadequate supply of raw materials and energy and inhibit the malignant behaviours of HCC cells. In addition, LCAT is a reliable predictive biomarker for the efficacy of lenvatinib treatment in HCC patients, and the inhibition of FAO can increase lenvatinib sensitivity in patients with LCATlow HCC. This study revealed that LCAT plays a critical role in the regulation of lipid metabolic reprogramming and is a reliable predictive biomarker for the efficacy of lenvatinib treatment in HCC patients.

Necroptosis, a distinct form of regulated necrosis implicated in various human pathologies, is orchestrated through sophisticated signaling pathways. During this process, cells undergoing necroptosis exhibit characteristic necrotic morphology and provoke substantial inflammatory responses. Post-translational modifications (PTMs)—chemical alterations occurring after protein synthesis that critically regulate protein functionality—constitute essential regulatory components within these complex signaling cascades. This intricate crosstalk between necroptotic pathways and PTM networks presents promising therapeutic opportunities. Our comprehensive review systematically analyzes the molecular mechanisms underlying necroptosis, with particular emphasis on the regulatory roles of PTMs in signal transduction. Through systematic evaluation of key modifications including ubiquitination, phosphorylation, glycosylation, methylation, acetylation, disulfide bond formation, caspase cleavage, nitrosylation, and SUMOylation, we examine potential therapeutic applications targeting necroptosis in disease pathogenesis. Furthermore, we synthesize current pharmacological strategies for manipulating PTM-regulated necroptosis, offering novel perspectives on clinical target development and therapeutic intervention.

Background and Aims:Sterol regulatory element-binding protein 1 (SREBP1), a key regulator of lipogenesis, is highly expressed in tumors, but the mechanisms sustaining its elevated levels remain unclear. The role of UFMylation, a posttranslational modification, in modulating SREBP1 stability and tumor progression has not been explored. This study aimed to investigate the role of UFMylation in the progression of liver cancer. Methods:Liquid chromatography-tandem mass spectrometry was employed to investigate the interacting proteins of ubiquitin-fold modifier 1-specific ligase 1 (UFL1). Knockdown of UFL1 and DDRGK domain-containing protein 1 (DDRGK1) was performed to assess SREBP1 stability. In vitro and in vivo models of hepatocellular carcinoma (HCC) were used to evaluate tumor progression. Clinical correlations between UFL1/DDRGK1 and SREBP1 levels were analyzed in HCC patient samples. Results:SREBP1 undergoes UFMylation, which synergizes with ubiquitination to reduce its stability. Depletion of UFL1 or DDRGK1 increased SREBP1 stability, driving HCC progression. Clinically, UFL1 and DDRGK1 levels were reduced in HCC tissues and inversely correlated with SREBP1 expression. Fatostatin (an SREBP1 inhibitor) enhanced the therapeutic effect of Lenvatinib in HCC models with low UFL1 expression. Conclusions:UFMylation is a critical posttranslational modification that destabilizes SREBP1, and its dysregulation contributes to HCC progression. Targeting the UFMylation-SREBP1 axis, particularly through Fatostatin and Lenvatinib combination therapy, represents a novel therapeutic strategy for HCC.

The development and progression of gastrointestinal (GI) cancers not only depend on the malignancy of the tumor cells, but is also defined by the complex and adaptive nature of the tumor microenvironment (TME). The TME in GI cancers exhibits a complex internal structure, typically comprising cancer cells, cancer stem cells, cancer-associated fibroblasts, immune cells, and endothelial cells, all embedded within a dynamic extracellular matrix. This intricate ecosystem fuels tumor initiation, progression, metastasis, recurrence and therapy response through the heterogeneity and plasticity. Recent advances in single-cell sequencing have provided unprecedented resolution in profiling the cellular diversity and interactions within the TME. These technologies have uncovered previously unknown cell subtypes and intricate communication networks that drive therapy resistance and tumor relapse. In this review, we summarize and discuss the latest findings from single-cell sequencing of key cellular players and their interactions within the TME of GI cancers. We highlight single cell insights that are reshaping our understanding of tumor biology, with particular focus on their implications for overcoming therapy resistance and improving clinical outcomes. We believe that a deeper understanding of TME heterogeneity and plasticity at the single-cell level promises to transform the landscape of precision treatment in GI cancers.

The proteomic heterogeneity of gastric adenocarcinoma (GC) has been extensively investigated at the bulk tissue level, which can only provide an average molecular state. In this study, we collected an in-depth quantitative proteomic dataset of tissues and interstitial fluids (ISFs) from both poorly and non-poorly differentiated GC and presented a comprehensive analysis from several perspectives. Comparison of proteomes between ISFs and tissues revealed that ISF exhibited higher abundances of proteins associated with blood microparticles, protein-lipid complexes, immunoglobulin complexes, and high-density lipoprotein particles. Also, consistent and inconsistent protein abundance changes between them were revealed by a correlation analysis. Interestingly, a more pronounced difference between tumors and normal adjacent tissues was found at the ISF level, which accurately reflected tissue properties compared to those of bulk tissue. Two ISF-derived biomarker candidates, calsyntenin-1 (CLSTN1) and prosaposin (PSAP), were identified by distinguishing patients with different differentiation statuses and were further validated in serum samples. Additionally, the silencing of CLSTN1 and PSAP was demonstrated to suppress cell proliferation, migration, and invasion in poorly differentiated gastric cancer cell lines. In summary, the ISF proteome offers a new perspective on tumor biology. This study provides a valuable resource that significantly enhances the understanding of GC and may ultimately benefit clinical practice.

Representative IHC staining images of p53 protein in murine liver tumor tissues in the indicated groups. Scale bar: 50 μm.

(A-B) Flow cytometry assays of tumor infiltration proportions of CD11b+ F4/80+ MHC-II+ macrophages and CD3+ CD8+ PD-1+ T cells in orthotopic Hepa1-6 tumors with Slamf7 overexpression and control groups. (C) Heatmap showing the immunological activity ssGSEA scores in tumor samples from TCGA-LIHC cohort. The upper horizontal bars represent the expression level of SLAMF7. (D) Correlation matrix showing the relationships between SLAMF7 level and various immune activity scores in tumors from TCGA-LIHC cohort. (E) Violin diagrams showing the percentages of 22 immune cell types calculated using the CIBERSORT method in HCC tumors with SLAMF7 high and low expression groups. (F) The standardized risk score of a T cell exhaustion (TEX) signature between tumors with low and high SLAMF7 expression in the TCGA-LIHC cohort. (G) Correlation of the risk score of a M2-like macrophage-related gene signature with mRNA level of SLAMF7 in GSE14520 cohort. (H) Immunologic signature gene sets enriched in HCC with high SLAMF7 expression from TCGA-LIHC cohort. Student’s t test.

(A) Immunoblot assay of SHB protein level in the indicated HCC cells. (B-C) Immunoblot assays of phosphorylated and non-phosphorylated SHIP1, and K63-linked ubiquitinated TRAF6 level in the indicated HCC cells with and without SHB silence.

(A) Representative IHC staining images showing the expressions of SLAMF7 and CCL2 in HCC samples. Scale bar: 200 μm (left) and 20 μm (right). (B) The prognostic prediction performances of SLAMF7 in combination with CCL2 for OS and DFS in our Fudan LCI HCC cohort.

(A) The liver and kidney functions of C57BL/6 mice with orthotopic Hepa1-6 tumors receiving RS102895 and anti-PD-1 antibody monotherapy or combination therapy at the study endpoint. (B) Gross appearance of the liver bearing Hepa1-6-shSlamf7 tumors in the indicated treatment groups. (C) The tumor weight and tumor volume of each group at the study endpoint (5 mice per group). (D) Gross appearance of the liver bearing Hepa1-6-Slamf7 tumors in the indicated treatment groups. (E) The tumor weight and tumor volume of each group at the study endpoint (5 mice per group). (F) Schematic showing the schedule of elotuzumab treatment in mice bearing MM and HCC subcutaneous tumors. (G) Gross appearance of the subcutaneous tumors from the indicated groups. (H) The tumor weight of each group at the endpoint. (I) Volumes of subcutaneous tumors in each group during treatment. NS, not significant, ***P<0.001, one-way ANOVA with a post hoc LSD test (or Student’s t test in part H and I).

(A) Flow cytometry analyses of CD80 and CD206 expressions in THP-1-differentiated macrophages cocultured with the indicated HCC cells. (B) Flow cytometry analyses of MHC-II and CD206 expressions in BMDMs cocultured with the indicated HCC cells. (C) qPCR analyses of M1 and M2 marker genes transcription levels in BMDMs cocultured with the indicated HCC cells. (D-E) Chemotaxis assays showing the effect of supernatants from the indicated coculture systems on the migration ability of THP-1-differentiated macrophages and BMDMs. Scale bar: 100 μm. (F) The correlations of intra-tumoral SLAMF7 expression with CXCL10, CXCL9, and ARG1 expression in TCGA-LIHC cohort. (G) The prognostic prediction performances of SLAMF7 in combination with CD68, CD80, and CD206 for OS in our Fudan LCI HCC cohort. *P<0.05, **P<0.01, and ***P<0.001, Student’s t test. Experiments were repeated three time and results were present as the mean ± SD.

(A) Representative IHC staining images showing the expressions of SLAMF7, p-STAT1, and p-STAT3 in HCC samples from Fudan LCI cohort. Scale bar: 200 μm (left) and 20 μm (right). (B) Representative immunofluorescence staining (left) and the infiltration levels (right) of exhausted T cells (CD8+ PD-1+ TCF1-) in HCC tumors with high and low SLAMF7 protein expression in the Fudan LCI cohort. Scale bar: 20μm. *P<0.05, Student’s t test.

Purpose: Cathepsin V (CTSV) is a cysteine protease peptidase, which is typically upregulated in cancer and is associated with various oncogenic processes, such as angiogenesis, proliferation, apoptosis, and invasion. The study explored the role of CTSV in hepatocellular carcinoma (HCC) and its potential as a potential biomarker. Patients and Methods: This study collected tumor and peritumoral archived specimens from 180 HCC patients who underwent surgical resection at Zhongshan Hospital, Fudan University (Shanghai, China) between 2009 and 2010. We extracted data from the TCGA and GEO databases and conducted differential expression analysis, univariate Cox regression, and Kaplan-Meier analysis. Ultimately, we determined that CTSV may emerge as a potential biomarker. Then, immunohistochemical staining for CTSV was performed on tumors and adjacent tissues of HCC patients, and a Cox proportional hazards model was constructed to evaluate the prognostic significance of CTSV expression levels. Applied functional enrichment analysis to reveal the underlying molecular mechanisms. Utilized ssGSEA enrichment analysis and TIMER2.0 algorithm to explore the correlation between CTSV expression and immune cells in HCC. In vitro and in vivo experiments were conducted using human liver cancer cell lines to further validate the clinical application value of CTSV. Results: In this study, we observed that CTSV expression was notably elevated in HCC (P < 0.001), and identified a significant association between elevated CTSV expression and reduced overall survival rates in patients. In vitro and in vivo experiments indicated that CTSV knockdown could significantly inhibit the proliferation, migration, and invasion of liver cancer cells, and it was found that the combination of CTSV knockdown with PD-1 inhibitors might enhance the therapeutic effect of PD-1 inhibitors in HCC. Conclusion: CTSV serves as a standalone negative prognostic indicator and possesses clinical significance in HCC.

Increasing evidence highlights that fibroblast growth factor receptor 2 (FGFR2) fusion/rearrangement shows important therapeutic value for patients with intrahepatic cholangiocarcinoma (ICC). This study aims to explore the association of FGFR2 status with the prognosis and immune cell infiltration profiles of patients with ICC. A total of 226 ICC tissue samples from patients who received surgery at the Department of Liver Surgery at Zhongshan Hospital, Fudan University, were collected retrospectively and assigned to a primary cohort (n = 152) and validation cohort (n = 74) group. Fluorescence in situ hybridization was performed to determine FGFR2 status. Multiplex immunofluorescence (mIF) staining and immunohistochemistry were performed to identify immune cells. Thirty-two (14.2%) ICC tissues presented with FGFR2 fusion/rearrangement. FGFR2 fusion/rearrangement was associated with low levels of carcinoembryonic antigen (CEA, P = .026) and gamma glutamyl transferase (γ-GGT, P = .003), low TNM (P = .012), CNLC (P = .008) staging as well as low tumor cell differentiation (P = .016). Multivariate COX regression analyses revealed that FGFR2 fusion/rearrangement was an independent protective factor for both overall survival (OS) and relapse-free survival in patients with ICC. Furthermore, correlation analysis revealed that an FGFR2 fusion/rearrangement was associated with low levels of Tregs and N2 neutrophils and high levels of N1 neutrophils infiltrating into tumors but not with CD8+ T-cell or macrophage tumor infiltration. FGFR2 fusion/rearrangement may exert a profound impact on the prognosis of ICC patients and reprogram the tumor microenvironment to be an immune-activated state. FGFR2 status may be used for ICC prognostic stratification and as an immunotherapeutic target in patients with ICC.

CircRNAs participates in the development and occurrence of multiple tumor types. However, the specific effects and underlying mechanisms of circRNA in intrahepatic cholangiocarcinoma (ICC) progression and recurrence remain poorly understood. CircRNA sequencing was performed to screen circRNAs related to ICC recurrence after surgery using 53 ICC frozen tumor specimens. We found that compared with patients who experienced postsurgical recurrence, circFOXP1 had high expression in tumor tissues from patients with no postoperative recurrence. Functional experiments revealed that circFOXP1 inhibited ICC progression in vitro and in vivo. We then found that circFOXP1 inhibited ICC progression via encoding a novel protein, circFOXP1-231aa. Mechanistically, circFOXP1-231aa directly interacted with OTUD4, which regulates NCOA4 protein stability via deubiquitination modification, and thereby enhances ferroptosis of ICC cells. Examination of clinical ICC samples found positive correlations between circFOXP1 expression levels and levels of OTUD4 and NCOA4. These three factors are predictors of prognosis in patients with ICC. Collectively, we identified circFOXP1 encoded circFOXP1-231aa, which interacted with OTUD4 to suppress ubiquitination of NCOA4 and, thereby, promoted ferroptosis and inhibited ICC recurrence.

(A) The mRNA expression of SLAMF7 between peri-tumor (PT) and tumor (TT) tissues of GSE14520 cohort (n=247). (B) qPCR and immunoblot assays of SLAMF7 expression in hepatic cell line L-02 and HCC cell lines. (C) qPCR and immunoblot assays verifying the knockdown and overexpression efficiency of SLAMF7 in HCC cells. (D-E) CCK8 and migration assays showing the effect of SLAMF7 on the proliferative and migration abilities of HCC cells. (F-G) Left: Gross appearance of the liver bearing orthotopic Hepa1-6 tumors with and without Slamf7 overexpression from C57BL/6 and NOG mice. Right: The tumor weight and tumor volume of each group (5 mice per group). (H-I) Representative H&E staining images of lungs (left) and the incidence of lung metastasis (right) in the indicated orthotopic HCC mouse models from C57BL/6 and NOG mice. Scale bar: 500 μm (top) and 100 μm (bottom). ***P<0.001, and NS, not significant. Student’s t test (or one-way ANOVA with a post hoc LSD test in part A). Experiments were repeated three time and results were present as the mean ± SD.