Interface Energy-Level Reorganization for Efficient Perovskite γ-Ray Detectors.

Metal halide perovskites are promising candidates for γ-ray spectrum detectors. However, achieving high-resolution energy spectra in single-photon pulse-height analysis mode remains challenging, due to the inevitable leakage currents degrade the recognizable fingerprint energies which is critical for resolving γ-ray spectroscopy. We demonstrate under high bias voltage, a deficient contact barrier can lead to excessive surface charge injection, thereby increasing leakage current from electrodes to perovskites. Hence, we conceive to employ surface ligand engineering on perovskite single crystals to manipulate energy levels to suppress leakage current. In particular, anchoring a strong dipole ligand onto the perovskite induced surface charge-density displacement, leading to a downward band bending and heightened the corresponding contact barrier. Consequently, the strategy minimized the detectors'leakage current by an order of magnitude, to as low as 44 nA cm-2. The resulting detectors show a significant improvement in energy resolution, 3.9% for 22Na 511 keV γ-rays has been achieved at room temperature. The resulting detector further resolves each fingerprint energy for 152Eu γ-spectrum, representing one of the best γ-rays perovskite detectors reported to date. Moreover, the detectors exhibited stabilized energy resolution without any degradation under a continuous electric field for over 300 minutes, representing the longest longevity reported to date.

Enhancing organoid culture: harnessing the potential of decellularized extracellular matrix hydrogels for mimicking microenvironments.

Over the past decade, organoids have emerged as a prevalent and promising research tool, mirroring the physiological architecture of the human body. However, as the field advances, the traditional use of animal or tumor-derived extracellular matrix (ECM) as scaffolds has become increasingly inadequate. This shift has led to a focus on developing synthetic scaffolds, particularly hydrogels, that more accurately mimic three-dimensional (3D) tissue structures and dynamics in vitro. The ECM-cell interaction is crucial for organoid growth, necessitating hydrogels that meet organoid-specific requirements through modifiable physical and compositional properties. Advanced composite hydrogels have been engineered to more effectively replicate in vivo conditions, offering a more accurate representation of human organs compared to traditional matrices. This review explores the evolution and current uses of decellularized ECM scaffolds, emphasizing the application of decellularized ECM hydrogels in organoid culture. It also explores the fabrication of composite hydrogels and the prospects for their future use in organoid systems.

Hepatocyte-specific Smad4 deficiency inhibits hepatocarcinogenesis by promoting CXCL10/CXCR3-dependent CD8+- T cell-mediated anti-tumor immunity.

Rationale: Sma mothers against decapentaplegic homologue 4 (Smad4) is a key mediator of the transforming growth factor ß (TGF-ß) pathway and plays complex and contradictory roles in hepatocellular carcinoma (HCC). However, the specific role of Smad4 in hepatocytes in regulating hepatocarcinogenesis remains poorly elucidated. Methods: A diethylnitrosamine/carbon tetrachloride-induced HCC model was established in mice with hepatocyte-specific Smad4 deletion (AlbSmad4-/-) and liver tumorigenesis was monitored. Immune cell infiltration was examined by immunofluorescence and fluorescence activated cell sorting (FACS). Cytokine secretion, glycolysis, signal pathway, and single-cell RNA sequencing were analysed for mechanism. Results: AlbSmad4-/- mice exhibited significantly fewer and smaller liver tumor nodules, less fibrosis, reduced myeloid-derived suppressor cell infiltration and increased CD8+ T cell infiltration. Smad4 deletion in hepatocytes enhanced C-X-C motif ligand 10 (CXCL10) secretion, promoting tumor necrosis factor-α (TNF-α) production in CD8+ T cells. The loss of Smad4 activated the CXCL10/mammalian target of rapamycin (mTOR)/lactate dehydrogenase A (LDHA) pathway, which increased glycolytic activity in CD8+ T cells. HCC patients with high Smad4 expression exhibited decreased CD8+ T cell infiltration and altered glycolysis. Conclusion: Our results demonstrate that Smad4 in hepatocytes promotes hepatocarcinogenesis and is a potential and candidate target for the prevention and therapy of HCC.

Deubiquitinase Mysm1 regulates neural stem cell proliferation and differentiation by controlling Id4 expression.

Neural stem cells (NSCs) are critical for brain development and maintenance of neurogenesis. However, the molecular mechanisms that regulate NSC proliferation and differentiation remain unclear. Mysm1 is a deubiquitinase and is essential for the self-renewal and differentiation of several stem cells. It is unknown whether Mysm1 plays an important role in NSCs. Here, we found that Mysm1 was expressed in NSCs and its expression was increased with age in mice. Mice with Mysm1 knockdown by crossing Mysm1 floxed mice with Nestin-Cre mice exhibited abnormal brain development with microcephaly. Mysm1 deletion promoted NSC proliferation and apoptosis, resulting in depletion of the stem cell pool. In addition, Mysm1-deficient NSCs skewed toward neurogenesis instead of astrogliogenesis. Mechanistic investigations with RNA sequencing and genome-wide CUT&Tag analysis revealed that Mysm1 epigenetically regulated Id4 transcription by regulating histone modification at the promoter region. After rescuing the expression of Id4, the hyperproliferation and imbalance differentiation of Mysm1-deficient NSCs was reversed. Additionally, knockdown Mysm1 in aged mice could promote NSC proliferation. Collectively, the present study identified a new factor Mysm1 which is essential for NSC homeostasis and Mysm1-Id4 axis may be an ideal target for proper NSC proliferation and differentiation.

Recent advances in chemometric modelling of inhibitors against SARS-CoV-2.

The outbreak of the novel coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused great harm to all countries worldwide. This disease can be prevented by vaccination and managed using various treatment methods, including injections, oral medications, or aerosol therapies. However, the selection of suitable compounds for the research and development of anti-SARS-CoV-2 drugs is a daunting task because of the vast databases of available compounds. The traditional process of drug research and development is time-consuming, labour-intensive, and costly. The application of chemometrics can significantly expedite drug R&D. This is particularly necessary and important for drug development against pandemic public emergency diseases, such as COVID-19. Through various chemometric techniques, such as quantitative structure-activity relationship (QSAR) modelling, molecular docking, and molecular dynamics (MD) simulations, compounds with inhibitory activity against SARS-CoV-2 can be quickly screened, allowing researchers to focus on the few prioritised candidates. In addition, the ADMET properties of the screened candidate compounds should be further explored to promote the successful discovery of anti-SARS-CoV-2 drugs. In this case, considerable time and economic costs can be saved while minimising the need for extensive animal experiments, in line with the 3R principles. This paper focuses on recent advances in chemometric modelling studies of COVID-19-related inhibitors, highlights current limitations, and outlines potential future directions for development.

Effective TME-related signature to predict prognosis of patients with head and neck squamous cell carcinoma.

Introduction: The tumor microenvironment (TME) is crucial for the development of head and neck squamous cell carcinoma (HNSCC). However, the correlation of the characteristics of the TME and the prognosis of patients with HNSCC remains less known. Methods: In this study, we calculated the immune and stromal cell scores using the "estimate" R package. Kaplan-Meier survival and CIBERSORT algorithm analyses were applied in this study. Results: We identified seven new markers: FCGR3B, IGHV3-64, AC023449.2, IGKV1D-8, FCGR2A, WDFY4, and HBQ1. Subsequently, a risk model was constructed and all HNSCC samples were grouped into low- and high-risk groups. The results of both the Kaplan-Meier survival and receiver operating characteristic curve (ROC) analyses showed that the prognosis indicated by the model was accurate (0.758, 0.756, and 0.666 for 1-, 3- and 5-year survival rates). In addition, we applied the CIBERSORT algorithm to reveal the significant differences in the infiltration levels of immune cells between the two risk groups. Discussion: Our study elucidated the roles of the TME and identified new prognostic biomarkers for patients with HNSCC.

Bone-derived MSCs encapsulated in alginate hydrogel prevent collagen-induced arthritis in mice through the activation of adenosine A2A/2B receptors in tolerogenic dendritic cells.

Tolerogenic dendritic cells (tolDCs) facilitate the suppression of autoimmune responses by differentiating regulatory T cells (Treg). The dysfunction of immunotolerance results in the development of autoimmune diseases, such as rheumatoid arthritis (RA). As multipotent progenitor cells, mesenchymal stem cells (MSCs), can regulate dendritic cells (DCs) to restore their immunosuppressive function and prevent disease development. However, the underlying mechanisms of MSCs in regulating DCs still need to be better defined. Simultaneously, the delivery system for MSCs also influences their function. Herein, MSCs are encapsulated in alginate hydrogel to improve cell survival and retention in situ, maximizing efficacy in vivo. The three-dimensional co-culture of encapsulated MSCs with DCs demonstrates that MSCs can inhibit the maturation of DCs and the secretion of pro-inflammatory cytokines. In the collagen-induced arthritis (CIA) mice model, alginate hydrogel encapsulated MSCs induce a significantly higher expression of CD39+CD73+ on MSCs. These enzymes hydrolyze ATP to adenosine and activate A2A/2B receptors on immature DCs, further promoting the phenotypic transformation of DCs to tolDCs and regulating naïve T cells to Tregs. Therefore, encapsulated MSCs obviously alleviate the inflammatory response and prevent CIA progression. This finding clarifies the mechanism of MSCs-DCs crosstalk in eliciting the immunosuppression effect and provides insights into hydrogel-promoted stem cell therapy for autoimmune diseases.

Highly Regio- and Enantioselective Cu/Pd Co-Catalyzed Allylic Alkylation of α-pyridyl-α-fluoroesters: Construction of Quaternary C-F Stereocenters.

New methods for preparation of chiral alkyl fluorides have been studied intensively in recent years due to the favorable physicochemical and biological properties of those structures. Herein, we describe the regio- and enantioselective allylic alkylation of α-pyridyl-α-fluoroesters with allyl acetates promoted by Cu/Pd synergistic catalysis, constructing the carbon- fluorine quaternary stereocenters. In this co-catalytic system, palladium catalyst mainly constructed the C-C bond, while chiral copper catalyst controlled the enantioselectivity. A series of aryl- and aliphatic-substituted allyl acetates are applied, giving the corresponding products in high yield, excellent enantioselectivity, and E/Z (up to 98% yield, 98 : 2 er, E/Z>20 : 1).

Single-cell dissection of cellular and molecular features underlying human cervical squamous cell carcinoma initiation and progression.

Cervical squamous cell carcinoma (CESC) is a prototypical human cancer with well-characterized pathological stages of initiation and progression. However, high-resolution knowledge of the transcriptional programs underlying each stage of CESC is lacking, and important questions remain. We performed single-cell RNA sequencing of 76,911 individual cells from 13 samples of human cervical tissues at various stages of malignancy, illuminating the transcriptional tumorigenic trajectory of cervical epithelial cells and revealing key factors involved in CESC initiation and progression. In addition, we found significant correlations between the abundance of specific myeloid, lymphoid, and endothelial cell populations and the progression of CESC, which were also associated with patients' prognosis. Last, we demonstrated the tumor-promoting function of matrix cancer-associated fibroblasts via the NRG1-ERBB3 pathway in CESC. This study provides a valuable resource and deeper insights into CESC initiation and progression, which is helpful in refining CESC diagnosis and for the design of optimal treatment strategies.

Genetic and Pharmacological Inhibition of Astrocytic Mysm1 Alleviates Depressive-Like Disorders by Promoting ATP Production.

Major depressive disorder (MDD) is a leading cause of disability worldwide. A comprehensive understanding of the molecular mechanisms of this disorder is critical for the therapy of MDD. In this study, it is observed that deubiquitinase Mysm1 is induced in the brain tissues from patients with major depression and from mice with depressive behaviors. The genetic silencing of astrocytic Mysm1 induced an antidepressant-like effect and alleviated the osteoporosis of depressive mice. Furthermore, it is found that Mysm1 knockdown led to increased ATP production and the activation of p53 and AMP-activated protein kinase (AMPK). Pifithrin α (PFT α) and Compound C, antagonists of p53 and AMPK, respectively, repressed ATP production and reversed the antidepressant effect of Mysm1 knockdown. Moreover, the pharmacological inhibition of astrocytic Mysm1 by aspirin relieved depressive-like behaviors in mice. The study reveals, for the first time, the important function of Mysm1 in the brain, highlighting astrocytic Mysm1 as a potential risk factor for depression and as a valuable target for drug discovery to treat depression.

Hepatocyte-Specific Smad4 Deficiency Alleviates Liver Fibrosis via the p38/p65 Pathway.

Liver fibrosis is a wound-healing response caused by the abnormal accumulation of extracellular matrix, which is produced by activated hepatic stellate cells (HSCs). Most studies have focused on the activated HSCs themselves in liver fibrosis, and whether hepatocytes can modulate the process of fibrosis is still unclear. Sma mothers against decapentaplegic homologue 4 (Smad4) is a key intracellular transcription mediator of transforming growth factor-ß (TGF-ß) during the development and progression of liver fibrosis. However, the role of hepatocyte Smad4 in the development of fibrosis is poorly elucidated. Here, to explore the functional role of hepatocyte Smad4 and the molecular mechanism in liver fibrosis, a CCl4-induced liver fibrosis model was established in mice with hepatocyte-specific Smad4 deletion (Smad4Δhep). We found that hepatocyte-specific Smad4 deficiency reduced liver inflammation and fibrosis, alleviated epithelial-mesenchymal transition, and inhibited hepatocyte proliferation and migration. Molecularly, Smad4 deletion in hepatocytes suppressed the expression of inhibitor of differentiation 1 (ID1) and the secretion of connective tissue growth factor (CTGF) of hepatocytes, which subsequently activated the p38 and p65 signaling pathways of HSCs in an epidermal growth factor receptor-dependent manner. Taken together, our results clearly demonstrate that the Smad4 expression in hepatocytes plays an important role in promoting liver fibrosis and could therefore be a promising target for future anti-fibrotic therapy.

Ectoderm-derived frontal bone mesenchymal stem cells promote traumatic brain injury recovery by alleviating neuroinflammation and glutamate excitotoxicity partially via FGF1.

BACKGROUND: Traumatic brain injury (TBI) leads to cell and tissue impairment, as well as functional deficits. Stem cells promote structural and functional recovery and thus are considered as a promising therapy for various nerve injuries. Here, we aimed to investigate the role of ectoderm-derived frontal bone mesenchymal stem cells (FbMSCs) in promoting cerebral repair and functional recovery in a murine TBI model. METHODS: A murine TBI model was established by injuring C57BL/6 N mice with moderate-controlled cortical impact to evaluate the extent of brain damage and behavioral deficits. Ectoderm-derived FbMSCs were isolated from the frontal bone and their characteristics were assessed using multiple differentiation assays, flow cytometry and microarray analysis. Brain repairment and functional recovery were analyzed at different days post-injury with or without FbMSC application. Behavioral tests were performed to assess learning and memory improvements. RNA sequencing analysis, immunofluorescence staining, and quantitative reverse-transcription polymerase chain reaction (qRT-PCR) were used to examine inflammation reaction and neural regeneration. In vitro co-culture analysis and quantification of glutamate transportation were carried out to explore the possible mechanism of neurogenesis and functional recovery promoted by FbMSCs. RESULTS: Ectoderm-derived FbMSCs showed fibroblast like morphology and osteogenic differentiation capacity. FbMSCs were CD105, CD29 positive and CD45, CD31 negative. Different from mesoderm-derived MSCs, FbMSCs expressed the ectoderm-specific transcription factor Tfap2ß. TBI mice showed impaired learning and memory deficits. Microglia and astrocyte activation, as well as neural damage, were significantly increased post-injury. FbMSC application ameliorated the behavioral deficits of TBI mice and promoted neural regeneration. RNA sequencing analysis showed that signal pathways related to inflammation decreased, whereas those related to neural activation increased. Immunofluorescence staining and qRT-PCR data revealed that microglial activation and astrocyte polarization to the A1 phenotype were suppressed by FbMSC application. In addition, FGF1 secreted from FbMSCs enhanced glutamate transportation by astrocytes and alleviated the cytotoxic effect of excessive glutamate on neurons. CONCLUSIONS: Ectoderm-derived FbMSC application significantly alleviated neuroinflammation, brain injury, and excitatory toxicity to neurons, improved cognition and behavioral deficits in TBI mice. Therefore, ectoderm-derived FbMSCs could be ideal therapeutic candidates for TBI which mostly affect cells from the same embryonic origins as FbMSCs.

Enhanced catalytic reduction of p-nitrophenol and azo dyes on copper hexacyanoferrate nanospheres decorated copper foams.

Catalytic reduction of nitroaromatic compounds using low-cost non-precious metal containing catalyst remains an essential topic in wastewater treatment. Herein, copper hexacyanoferrate nanospheres decorated copper foams (CF) were prepared by a facile method, and it was used as structured catalysts for the reduction of p-nitrophenol (p-NP) and azo dyes. The catalyst obtained by calcination at 200 °C shows the highest catalytic activity, with an almost complete reduction of p-NP within 3 min with a rate of 2.057 min-1 at room temperature, and it exhibited excellent reusability in successive 6 cycles. The effects of temperature, initial concentration, pH, and flow rate on p-NP reduction were investigated. Moreover, the mechanistic investigation revealed that fast electron transfer ability and enhanced adsorption for p-NP contributed to its enhanced catalytic performances. This work put forward an efficient approach for the construction of structured catalysts with enhanced performance in catalytic reduction applications.

Steroidal saponins from Trillium tschonoskii rhizome repress cancer stemness and proliferation of intrahepatic cholangiocarcinoma.

A phytochemical study was carried out on the extract of Trillium tschonoskii rhizomes, resulting in the isolation of thirty-six steroidal glycosides (1-36). Their structures were established mainly by spectroscopic analyses as well as necessary chemical evidence, of which 1-25 were identified as new analogues. Herein, all the isolated analogues were screened for the cytotoxicity against intrahepatic cholangiocarcinoma (ICC) cell lines of HuCCT1 and RBE through tumor colony formation and CCK-8 survival analysis, and the results demonstrated that three compounds 9, 12, and 26 significantly repressed tumor colony and sphere formation in both cell lines, respectively. Furthermore, the three analogues possessed a remarkable inhibitory role of organoid formation established from hydrodynamic induced mouse primary intrahepatic cholangiocarcinoma. Moreover, the functional assays of flow cytometry analysis, cancer stemness related gene expression, and western blotting assays all indicated that compound 26 could significantly repress cancer stem markers. Taken together, these results demonstrate that steroidal glycosides derived from T. tschonoskii rhizomes could be potentially implicated in human ICC therapy.

MicroRNA-377-3p inhibits hepatocellular carcinoma growth and metastasis through negative regulation of CPT1C-mediated fatty acid oxidation.

BACKGROUND: Altered lipid metabolism is closely related to the occurrence and development of hepatocellular carcinoma (HCC). Carnitine palmitoyltransferase 1C (CPT1C) is a member of CPT1 family and plays a key role in cancer development and progression. However, how microRNAs (miRNAs) regulate CPT1C-mediated fatty acid transport and oxidation remains to be elucidated. METHODS: Oil Red O staining, mitochondrial, and lipid droplets immunofluorescence staining were used to detect the functions of miR-377-3p and CPT1C in fatty acid oxidation. Colocalization of palmitate and mitochondria was performed to investigate the function of miR-377-3p and CPT1C in fatty acid transport into mitochondria. Fatty acid oxidation (FAO) assay was used to detect the function of miR-377-3p and CPT1C in FAO. Cell proliferation, migration and invasion assays and animal experiments were used to evaluate the role of miR-377-3p/CPT1C axis in HCC progression in vitro and in vivo. Immunofluorescence staining was used to identify the clinical significance of miR-377-3p and CPT1C in HCC patients. RESULTS: MiR-377-3p inhibits CPT1C expression by targeting its 3'-untranslated region. Through repression of CPT1C, miR-377-3p suppresses fatty acid oxidation by preventing fatty acid from entering into mitochondria and decreasing ATP production in HCC cells. Inhibiting fatty acid oxidation abolishes the ability of miR-377-3p/CPT1C axis to regulate HCC proliferation, migration, invasion and metastasis in vitro and in vivo. In HCC patients, CPT1C is significantly upregulated, and miR-377-3p expression and lipid droplets are negatively correlated with CPT1C expression. High expression of miR-377-3p and CPT1C predict better and worse clinical outcomes, respectively. CONCLUSIONS: We uncover the key function and the relevant mechanisms of the miR-377-3p/CPT1C axis in HCC, which might provide a potential target for the treatment of HCC.

Screening a redox library identifies the anti-tumor drug Hinokitiol for treating intrahepatic cholangiocarcinoma.

AIMS: Intrahepatic cholangiocarcinoma (ICC) is a highly malignant and heterogeneous cancer with a poor prognosis. At present, there is no optimal treatment except for surgical resection, and recurrence after resection will lead to death due to multidrug resistance. Changes in the redox signal have been found to be closely related to the growth and drug resistance of tumor cells. Therefore, the purpose of this study was to screen small molecule compounds from the redox library to find a drug for anti-ICC and to explore its downstream mechanism. MATERIAL AND METHODS: Tumor clone and sphere formation of ICC cell lines, as well as mouse ICC organoid proliferation assays were utilized to screen the candidate drug in the Redox library. Western blotting, quantitative reverse-transcription polymerase chain reaction (qRT-PCR), as well as cell apoptosis and cell cycle flow cytometry assays were used to explore the mechanism. RESULTS: We found that Hinokitiol was a candidate drug through inhibition of tumor clone and sphere formation, and the expression of cancer stem cell (CSC)-related genes. Furthermore, Hinokitiol significantly inhibited the proliferation of ICC cells by downregulating the ERK and P38 pathways. In addition, the combination of Hinokitiol and Palbociclib showed a significant inhibitory effect on human ICC cells and mouse ICC organoids. CONCLUSION: Hinokitiol may have the potential to be developed as a clinical therapeutic drug for ICC treatment.

Efficient removal of organic pollutants by a Co/N/S-doped yolk-shell carbon catalyst via peroxymonosulfate activation.

Carbon-based catalysts with heteroatom doping and hollow structures are desired for advanced oxidation processes (AOPs). Herein, dual-shelled Co, N, and S codoped hollow carbon nanocages were developed by wrapping zeolitic imidazolate framework-67 (ZIF-67) with trithiocyanuric acid (TCA) and performing subsequent carbonization. The optimal composite catalyst (Co-NC-CoS) exhibited excellent catalytic performance toward different organic pollutants. Almost complete removal of 4-NP (60 mg/L-1) was achieved within 20 min by 10 mg of catalyst and 0.2 g/L-1 peroxymonosulfate (PMS). Moreover, the catalyst showed good stability and reusability. The effects of catalyst and PMS dose, pollutant concentration, pH and common anions were investigated, and reactive oxygen species (ROS) were studied by scavenger experiments and electron paramagnetic resonance (EPR) tests. The results show that multidoped atoms S, Co and N all contributed to the degradation system. Several lines of evidence suggested that S could change the catalytic process from Co3+/Co2+ to Co3+/Co2+/Co0 reduction due to its low redox potential. Degradation was achieved through both radical and nonradical pathways, where sulfate radicals (SO4·Ì¶), hydroxyl radicals (·OH) and singlet oxygen (1O2) were primary reactive species. Overall, this work may suggest that the novel multi heteroatom-doped catalysts with complex structures can be developed for environmental remediation.

Enhanced adsorption and catalytic peroxymonosulfate activation by metal-free N-doped carbon hollow spheres for water depollution.

Rational design of metal-free carbon-based heterogeneous catatlyst for wastewater remediation via peroxymonosulfate (PMS) activation is highly desirable. Here, hollow structured porous carbon with abundant N, a high graphitization degree, and a large specific surface area and pore volume (1301 m2/g and 1.12 cm3/g) was synthesized by the pyrolysis of core-shell structured composites consisting of polystyrene (PS) cores and Zeolitic imidazolate frameworks-8 (ZIF-8) shells. The hollow structured carbon (CPS@ZIF-8) was characterized thoroughly and applied for phenol degradation by the activation of PMS. The effects of operation conditions such as the catalyst and PMS dose, phenol concentration, initial pH, and temperature on phenol removal were investigated comprehensively. Moreover, the main reactive species involved in phenol oxidation were investigated, and a plausible mechanism for the degradation of phenol is proposed. The results show that CPS@ZIF-8 exhibited an excellent phenol adsorption and degradation performance, which can be mainly ascribed to its large surface area, abundance of nitrogen and hollow porous structure. Moreover, both the nonradical pathway (involving 1O2) and the radical pathway (involving SO4- and O2-) were found to be involved in the decomposition of phenol.

An overview of genetic mutations and epigenetic signatures in the course of pancreatic cancer progression.

Pancreatic cancer (PC) is assumed to be an intimidating and deadly malignancy due to being the leading cause of cancer-led mortality, predominantly affecting males of older age. The overall (5 years) survival rate of PC is less than 9% and is anticipated to be aggravated in the future due to the lack of molecular acquaintance and diagnostic tools for its early detection. Multiple factors are involved in the course of PC development, including genetics, cigarette smoking, alcohol, family history, and aberrant epigenetic signatures of the epigenome. In this review, we will mainly focus on the genetic mutations and epigenetic signature of PC. Multiple tumor suppressor and oncogene mutations are involved in PC initiation, including K-RAS, p53, CDKN2A, and SMAD4. The mutational frequency of these genes ranges from 50 to 98% in PC. The nature of mutation diagnosis is mostly homozygous deletion, point mutation, and aberrant methylation. In addition to genetic modification, epigenetic alterations particularly aberrant hypermethylation and hypomethylation also predispose patients to PC. Hypermethylation is mostly involved in the downregulation of tumor suppressor genes and leads to PC, while multiple genes also represent a hypomethylation status in PC. Several renewable drugs and detection tools have been developed to cope with this aggressive malady, but all are futile, and surgical resection remains the only choice for prolonged survival if diagnosed before metastasis. However, the available therapeutic development is insufficient to cure PC. Therefore, novel approaches are a prerequisite to elucidating the genetic and epigenetic mechanisms underlying PC progression for healthier lifelong survival.

Single-cell transcriptomic architecture and intercellular crosstalk of human intrahepatic cholangiocarcinoma.

BACKGROUND & AIMS: Intrahepatic cholangiocarcinoma (ICC) is the second most common liver malignancy. ICC typically features remarkable cellular heterogeneity and a dense stromal reaction. Therefore, a comprehensive understanding of cellular diversity and the interplay between malignant cells and niche cells is essential to elucidate the mechanisms driving ICC progression and to develop therapeutic approaches. METHODS: Herein, we performed single-cell RNA sequencing (scRNA-seq) analysis on unselected viable cells from 8 human ICCs and adjacent samples to elucidate the comprehensive transcriptomic landscape and intercellular communication network. Additionally, we applied a negative selection strategy to enrich fibroblast populations in 2 other ICC samples to investigate fibroblast diversity. The results of the analyses were validated using multiplex immunofluorescence staining, bulk transcriptomic datasets, and functional in vitro and in vivo experiments. RESULTS: We sequenced a total of 56,871 single cells derived from human ICC and adjacent tissues and identified diverse tumor, immune, and stromal cells. Malignant cells displayed a high degree of inter-tumor heterogeneity. Moreover, tumor-infiltrating CD4 regulatory T cells exhibited highly immunosuppressive characteristics. We identified 6 distinct fibroblast subsets, of which the majority were CD146-positive vascular cancer-associated fibroblasts (vCAFs), with highly expressed microvasculature signatures and high levels of interleukin (IL)-6. Functional assays indicated that IL-6 secreted by vCAFs induced significant epigenetic alterations in ICC cells, particularly upregulating enhancer of zeste homolog 2 (EZH2) and thereby enhancing malignancy. Furthermore, ICC cell-derived exosomal miR-9-5p elicited high expression of IL-6 in vCAFs to promote tumor progression. CONCLUSIONS: Our single-cell transcriptomic dataset delineates the inter-tumor heterogeneity of human ICCs, underlining the importance of intercellular crosstalk between ICC cells and vCAFs, and revealing potential therapeutic targets. LAY SUMMARY: Intrahepatic cholangiocarcinoma is an aggressive and chemoresistant malignancy. Better understanding the complex transcriptional architecture and intercellular crosstalk of these tumors will help in the development of more effective therapies. Herein, we have identified important interactions between cancer cells and cancer-associated fibroblasts in the tumor stroma, which could have therapeutic implications.