Identification and validation of inflammatory subtypes in intrahepatic cholangiocellular carcinoma.

BACKGROUND: Inflammation plays a critical role in tumor development. Inflammatory cell infiltration and inflammatory mediator synthesis cause changes in the tumor microenvironment (TME) in several cancers, especially in intrahepatic cholangiocellular carcinoma (ICC). However, methods to ascertain the inflammatory state of patients using reliable biomarkers are still being explored. METHOD: We retrieved the RNA sequencing and somatic mutation analyses results and the clinical characteristics of 244 patients with ICC from published studies. We performed consensus clustering to identify the molecular subtypes associated with inflammation. We compared the prognostic patterns, clinical characteristics, somatic mutation profiles, and immune cell infiltration patterns across inflammatory subtypes. We performed quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) to confirm gene expression. We performed logistic regression analyses to construct a nomogram predicting the inflammatory status of patients with ICC. RESULTS: Our results confirmed that ICC can be categorized into an inflammation-high subtype (IHS) and an inflammation-low subtype (ILS). Patients from each group had distinct prognosis, clinical characteristics, and TME composition. Patients with ICC in the IHS group showed poorer prognosis owing to the immunosuppressive microenvironment and high frequency of KRAS and TP53 mutations. Cancer-associated fibroblast (CAF)-derived COLEC11 reduced myeloid inflammatory cell infiltration and attenuated inflammatory responses. The results of qRT-PCR and IHC experiments confirmed that COLEC11 expression levels were significantly reduced in tumor tissues compared to those in paracancerous tissues. Patients with ICC in the IHS group were more likely to respond to treatment with immune checkpoint inhibitors (ICIs) owing to their higher tumor mutational burden (TMB) scores, tumor neoantigen burden (TNB) scores, neoantigen counts, and immune checkpoint expression levels. Finally, we developed a nomogram to effectively predict the inflammatory status of patients with ICC based on their clinical characteristics and inflammatory gene expression levels. We evaluated the calibration, discrimination potential, and clinical utility of the nomogram. CONCLUSION: The inflammatory response in IHS is primarily induced by myeloid cells. COLEC11 can reduce the infiltration level of this group of cells, and myeloid inflammatory cells may be a novel target for ICC treatment. We developed a novel nomogram that could effectively predict the inflammatory state of patients with ICC, which will be useful for guiding individualized treatment plans.

Histamine-related genes participate in the establishment of an immunosuppressive microenvironment and impact the immunotherapy response in hepatocellular carcinoma.

Chronic inflammation is pivotal in the pathogenesis of hepatocellular carcinoma (HCC). Histamine is a biologically active substance that amplifies the inflammatory and immune response and serves as a neurotransmitter. However, knowledge of histamine's role in HCC and its effects on immunotherapy remains lacking. We focused on histamine-related genes to investigate their potential role in HCC. The RNA-seq data and clinical information regarding HCC were obtained from The Cancer Genome Atlas (TCGA). After identifying the differentially expressed genes, we constructed a signature using the univariate Cox proportional hazard regression and least absolute shrinkage and selection operator (LASSO) analyses. The signature's predictive performance was evaluated using a receiver operating characteristic curve (ROC) analysis. Furthermore, drug sensitivity, immunotherapy effects, and enrichment analyses were conducted. Histamine-related gene expression in HCC was confirmed using quantitative real-time polymerase chain reaction (qRT-PCR). A histamine-related gene prognostic signature (HRGPS) was developed in TCGA. Time-dependent ROC and Kaplan-Meier survival analyses demonstrated the signature's strong predictive power. Importantly, patients in high-risk groups exhibited a higher frequency of TP53 mutations, elevated immune checkpoint-related gene expression, and increased infiltration of immunosuppressive cells-indicating a potentially favorable response to immunotherapy. In addition, drug sensitivity analysis revealed that the signature could effectively predict chemotherapy efficacy and sensitivity. qRT-PCR results validated histamine-related gene overexpression in HCC. Our findings demonstrate that inhibiting histamine-related genes and signaling pathways can impact the therapeutic effect of anti-PD-1/PD-L1. The precise predictive ability of our signature in determining the response to different therapeutic options highlights its potential clinical significance.

TGF-ß Promotes Hepatocellular Carcinoma Metastasis Through Through m6A Modification of PCDHGA9.

Objective: Hepatocellular carcinoma (HCC) is a highly lethal cancer with significant mortality, primarily attributed to metastasis. Although Protocadherin Gamma Subfamily A, 9 (PCDHGA9) has been identified as a tumor suppressor gene in cancer metastasis, its role in HCC remains ambiguous. This study aims to clarify the role of PCDHGA9 in HCC by examining its expression, clinical significance, and molecular activities. Methods: Tissue microarray immunofluorescence analysis evaluated the expression of PCDHGA9 and its clinical relevance. In vitro experiments involved manipulating PCDHGA9 levels in SK-HEP-1 cells to assess migration through wound-healing and transwell assays. In vivo, shPCDHGA9 cell injections were utilized to observe effects on tumor growth and metastasis. Protein analysis and Western Blot validated epithelial-mesenchymal transition (EMT)-related proteins. Subsequent to TGF-ß treatment, cell proliferation and apoptosis were quantified using Cell counting kit-8 and flow cytometry, respectively, followed by investigation of TGF-ß effects on PCDHGA9 N6-methyladenosine (m6A) modification via Methylated RNA immunoprecipitation, RT-qPCR, and Western blot analysis. Results: Downregulation of PCDHGA9 expression in HCC tissues is correlated with poor prognosis. In vitro experiments demonstrated that modulating PCDHGA9 expression influenced HCC cell migration. In vivo, PCDHGA9 knockdown is correlated with increased metastasis. Furthermore, TGF-ß stimulation promoted cell proliferation and inhibited apoptosis. Mechanistically, TGF-ß-mediated m6A modification led to PCDHGA9 decay, promoting EMT in HCC cells. Conclusion: PCDHGA9 serves as a potential tumor suppressor in HCC by inhibiting EMT. During this process, TGF-ß is observed to exert regulatory control over m6A modifications of PCDHGA9.

Predictive value of HTS grade in patients with intrahepatic cholangiocarcinoma undergoing radical resection: a multicenter study from China.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is a highly malignant tumor with a poor prognosis. This study aimed to investigate whether Hemoglobin, Albumin, Lymphocytes, and Platelets (HALP) score and Tumor Burden Score (TBS) serves as independent influencing factors following radical resection in patients with ICC. Furthermore, we sought to evaluate the predictive capacity of the combined HALP and TBS grade, referred to as HTS grade, and to develop a prognostic prediction model. METHODS: Clinical data for ICC patients who underwent radical resection were retrospectively analyzed. Univariate and multivariate Cox regression analyses were first used to find influencing factors of prognosis for ICC. Receiver operating characteristic (ROC) curves were then used to find the optimal cut-off values for HALP score and TBS and to compare the predictive ability of HALP, TBS, and HTS grade using the area under these curves (AUC). Nomogram prediction models were constructed and validated based on the results of the multivariate analysis. RESULTS: Among 423 patients, 234 (55.3%) were male and 202 (47.8) were aged ≥ 60 years. The cut-off value of HALP was found to be 37.1 and for TBS to be 6.3. Our univariate results showed that HALP, TBS, and HTS grade were prognostic factors of ICC patients (all P < 0.05), and ROC results showed that HTS had the best predictive value. The Kaplan-Meier curve showed that the prognosis of ICC patients was worse with increasing HTS grade. Additionally, multivariate regression analysis showed that HTS grade, carbohydrate antigen 19-9 (CA19-9), tumor differentiation, and vascular invasion were independent influencing factors for Overall survival (OS) and that HTS grade, CA19-9, CEA, vascular invasion and lymph node invasion were independent influencing factors for recurrence-free survival (RFS) (all P < 0.05). In the first, second, and third years of the training group, the AUCs for OS were 0.867, 0.902, and 0.881, and the AUCs for RFS were 0.849, 0.841, and 0.899, respectively. In the first, second, and third years of the validation group, the AUCs for OS were 0.727, 0.771, and 0.763, and the AUCs for RFS were 0.733, 0.746, and 0.801, respectively. Through the examination of calibration curves and using decision curve analysis (DCA), nomograms based on HTS grade showed excellent predictive performance. CONCLUSIONS: Our nomograms based on HTS grade had excellent predictive effects and may thus be able to help clinicians provide individualized clinical decision for ICC patients.

Herbivore exclusion stabilizes alpine grassland biomass production across spatial scales.

There is growing evidence that land-use management practices such as livestock grazing can strongly impact the local diversity, functioning, and stability of grassland communities. However, whether these impacts depend on environmental condition and propagate to larger spatial scales remains unclear. Using an 8-year grassland exclosure experiment conducted at nine sites in the Tibetan Plateau covering a large precipitation gradient, we found that herbivore exclusion increased the temporal stability of alpine grassland biomass production at both the local and larger (site) spatial scales. Higher local community stability was attributed to greater stability of dominant species, whereas higher stability at the larger scale was linked to higher spatial asynchrony of productivity among local communities. Additionally, sites with higher mean annual precipitation had lower dominant species stability and lower grassland stability at both the spatial scales considered. Our study provides novel evidence that livestock grazing can impair grassland stability across spatial scales and climatic gradients.

The interaction of climate, plant, and soil factors drives putative soil fungal pathogen diversity and community structure in dry grasslands.

Soil pathogens play important roles in shaping soil microbial diversity and controlling ecosystem functions. Though climate and local environmental factors and their influences on fungal pathogen communities have been examined separately, few studies explore the relative contributions of these factors. This is particularly crucial in eco-fragile regions, which are more sensitive to environmental changes. Herein we investigated the diversity and community structure of putative soil fungal pathogens in cold and dry grasslands on the Tibetan Plateau, using high-throughput sequencing. The results showed that steppe soils had the highest diversity of all pathogens and plant pathogens; contrastingly, meadow soils had the highest animal pathogen diversity. Structural equation modelling revealed that climate, plant, and soil had similar levels of influence on putative soil fungal pathogen diversity, with total effects ranging from 52% to 59% (all p < 0.001), with precipitation exhibiting a stronger direct effect than plant and soil factors. Putative soil fungal pathogen community structure gradually changed with desert, steppe, and meadow, and was primarily controlled by the interactions of climate, plant, and soil factors rather than by distinct factors individually. This finding contrasts with most studies of soil bacterial and fungal community structure, which generally report dominant roles of individual environmental factors.