Single-cell RNA sequencing reveals epithelial cells driving brain metastasis in lung adenocarcinoma.

Brain metastases (BM) of lung adenocarcinoma (LUAD) are the most common intracranial malignancy leading to death. However, the cellular origins and drivers of BM from LUAD have not been clarified. Cellular composition was characterized by single-cell sequencing analysis of primary lung adenocarcinoma (pLUAD), BM and lymph node metastasis (LNM) samples in GSE131907. Our study briefly analyzed the tumor microenvironment (TME), focusing on the role of epithelial cells (ECs) in BM. We have discovered a population of brain metastasis-associated epithelial cells (BMAECs) expressing SPP1, SAA1, and CDKN2A, and it has been observed that this population is mainly composed of aneuploid cells from pLUAD, playing a crucial role in brain metastasis. Our study concluded that both LNM and BM in LUAD originated from pLUAD lesions, but there is currently insufficient evidence to prove a direct association between BM lesions and LNM lesions, which provides inspiration for further investigation of the TME in BM.

A non-canonical role of endothelin converting enzyme 1 (ECE1) in promoting lung cancer development via directly targeting protein kinase B (AKT).

BACKGROUND: Lung cancer is the second most common malignancy in the world, and lung adenocarcinoma (LUAD) in particular is the leading cause of cancer death worldwide. Endothelin converting enzyme 1 (ECE1) is a membrane-bound metalloprotease involved in endothelin-1 (ET-1) processing and regulates vasoconstriction. However, very few studies have reported the involvement of ECE1 in regulating tumor cell proliferation, and the mechanism remains poorly understood. Therefore, we aimed to determine the role of ECE1 in lung cancer development. METHODS: The Cancer Genome Atlas database and Kaplan-Meier plotter were used to assess the association between ECE1 and lung cancer. The expression of ECE1 was detected using immunohistochemistry staining and western blotting. A variety of in vitro assays were performed to evaluate the effects of ECE1 on the colony formation, proliferation, migration and invasion using ECE1 knockdown lung cancer cells. The gene expression profiles regulated by ECE1 were investigated by RNA sequencing. An immunoprecipitation assay and immunofluorescence assay were used to evaluate the mechanism underlying the regulatory effect of ECE1 on protein kinase B (AKT). The effect of ECE1 on tumor development was assessed by xenografted lung cancer cells in either C57BL/6 mice or nude mice. RESULTS: ECE1 was upregulated in LUAD and correlated with the poor prognosis of patients with LUAD. Functional studies showed that knockdown of ECE1 retarded the progression of tumors formed by lung cancer cells at least partly by inhibiting tumor cell proliferation. Moreover, ECE1 accelerated tumor cell proliferation through promoting AKT activation dispensable of its canonical target ET-1. Mechanically, ECE1 interacted with the pleckstrin homology (PH) domain of AKT and facilitated its translocation to the plasma membrane for activation. Furthermore, the inhibition of AKT activity counteracted the lung cancer cell growth inhibition observed both in vitro and in xenografts caused by ECE1 suppression. CONCLUSIONS: The present study reveals a non-canonical function of ECE1 in regulating AKT activation and cell proliferation, which provides the basis for the development of a novel strategy for the intervention of cancer including LUAD by abrogating ECE1-AKT signaling.

Multiomics identifies metabolic subtypes based on fatty acid degradation allocating personalized treatment in hepatocellular carcinoma.

BACKGROUND AND AIMS: Molecular classification is a promising tool for prognosis prediction and optimizing precision therapy for HCC. Here, we aimed to develop a molecular classification of HCC based on the fatty acid degradation (FAD) pathway, fully characterize it, and evaluate its ability in guiding personalized therapy. APPROACH AND RESULTS: We performed RNA sequencing (RNA-seq), PCR-array, lipidomics, metabolomics, and proteomics analysis of 41 patients with HCC, in which 17 patients received anti-programmed cell death-1 (PD-1) therapy. Single-cell RNA sequencing (scRNA-seq) was performed to explore the tumor microenvironment. Nearly, 60 publicly available multiomics data sets were analyzed. The associations between FAD subtypes and response to sorafenib, transarterial chemoembolization (TACE), immune checkpoint inhibitor (ICI) were assessed in patient cohorts, patient-derived xenograft (PDX), and spontaneous mouse model ls. A novel molecular classification named F subtype (F1, F2, and F3) was identified based on the FAD pathway, distinguished by clinical, mutational, epigenetic, metabolic, and immunological characteristics. F1 subtypes exhibited high infiltration with immunosuppressive microenvironment. Subtype-specific therapeutic strategies were identified, in which F1 subtypes with the lowest FAD activities represent responders to compounds YM-155 and Alisertib, sorafenib, anti-PD1, anti-PD-L1, and atezolizumab plus bevacizumab (T + A) treatment, while F3 subtypes with the highest FAD activities are responders to TACE. F2 subtypes, the intermediate status between F1 and F3, are potential responders to T + A combinations. We provide preliminary evidence that the FAD subtypes can be diagnosed based on liquid biopsies. CONCLUSIONS: We identified 3 FAD subtypes with unique clinical and biological characteristics, which could optimize individual cancer patient therapy and help clinical decision-making.

A retrospective comparative cohort study: concurrent versus consolidative immunotherapy with chemoradiotherapy in EGFR- or ALK-negative unresectable stage III non-small cell lung cancer.

Background: The treatment of stage III non-small cell lung cancer (NSCLC) is very challenging because it is a heterogeneous group of diseases. This study was to investigative whether concurrent immunotherapy with chemoradiotherapy was associated with improved outcomes compared to consolidative immunotherapy following chemoradiotherapy in patients with unresectable stage III NSCLC, which may provide evidence-based medical evidence for the treatment of stage III NSCLC. Methods: A total of 78 epidermal growth factor receptor or anaplastic lymphoma kinase (EGFR/ALK) negative patients from the clinical database of the shanghai pulmonary hospital with locally advanced unresectable NSCLC and we evaluated them for baseline clinical factors, follow-up. Patients underwent concurrent immunotherapy with chemoradiotherapy or consolidative immunotherapy after chemoradiotherapy. Patients were classified based on initial site of progression (primary versus non-primary site). The study endpoints were progression-free survival (PFS) and time to death or distant metastasis (TDDM). Cox proportional hazards analysis was used to assess the factors affecting PFS and TDDM. Results: The median follow-up time for both groups was 26 months, and there was no significant difference in baseline clinical characteristics (P>0.05). The patients receiving concurrent immunotherapy (n=36) had a longer PFS than those receiving consolidative immunotherapy (n=42) (median 32.4 vs. 15.5 months; P<0.01). The TDDM was also longer in patients with concurrent immunotherapy than those with consolidative immunotherapy (median 57.3 vs. 31.0 months; P=0.01). Furthermore, in a subset of patients with initial site of progression at a non-primary-site, patients undergoing concurrent immunotherapy had longer PFS than those undergoing consolidative immunotherapy (median 22.7 vs. 11.9 months; P=0.03). Conclusions: Concurrent immunotherapy with chemoradiotherapy may be associated with improved disease progression outcomes as compared to consolidative immunotherapy following chemoradiotherapy.

Kidney-type glutaminase is a biomarker for the diagnosis and prognosis of hepatocellular carcinoma: a prospective study.

PURPOSE: The pathological diagnosis and prognosis prediction of hepatocellular carcinoma (HCC) is challenging due to the lack of specific biomarkers. This study aimed to validate the diagnostic and prognostic efficiency of Kidney-type glutaminase (GLS1) for HCC in prospective cohorts with a large sample size. METHODS: A total of 1140 HCC patients were enrolled in our prospective clinical trials. Control cases included 114 nontumour tissues. The registered clinical trial (ChiCTR-DDT-14,005,102, chictr.org.cn) was referred to for the exact protocol. GLS1 immunohistochemistry was performed on the whole tumour section. The diagnostic and prognostic performances of GLS1 was evaluated by the receiver operating characteristic curve and Cox regression model. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value, Youden index, and area under the curve of GLS1 for the diagnosis of HCC were 0.746, 0.842, 0.979, 0.249, 0.588, and 0.814, respectively, which could be increased to 0.846, 0.886, 0.987,0.366, 0.732, and 0.921 when combined with glypican 3 (GPC3) and alpha-fetoprotein (AFP), indicating better diagnostic performance. Further, we developed a nomogram with GPC3 and GLS1 for identifying HCC which showed good discrimination and calibration. GLS1 expression was also related with age, T stage, TNM stage, Edmondson-Steiner grade, microvascular invasion, Ki67, VEGFR2, GPC3, and AFP expression in HCC. GLS1 expression was negatively correlated with disease-free survival (P < 0.001) probability of patients with HCC. CONCLUSIONS: It was validated that GLS1 was a sensitive and specific biomarker for pathological diagnosis of HCC and had prognostic value, thus having practical value for clinical application.

(-)-Guaiol inhibit epithelial-mesenchymal transition in lung cancer via suppressing M2 macrophages mediated STAT3 signaling pathway.

In the context of cancer expansion, epithelial-mesenchymal transition (EMT) plays an essential role in driving invasion and metastasis potential of cancer cells. Tumor-associated macrophages (TAMs)-derived factors involved in the initiation and progression of EMT. We assess the role of M2 macrophage in suppressing lung tumors of a natural compound (-)-Guaiol by using macrophage depleted model. Bone marrow-derived monocytes (BMDMs) were extracted and induced to M2-like phenotype in vitro. The co-culture of M2 macrophage and lung cancer cells was established to observe that inhibition of lung tumor growth by (-)-Guaiol requires presence of macrophages. This suppressed effect of (-)-Guaiol was alleviated when mice macrophage was depleted. The expression of M2-like macrophages was strongly reduced by (-)-Guaiol treated mice, but not the changes of M1-like macrophages. In vitro studies, we demonstrated that (-)-Guaiol suppressed M2 polarization of BMDMs, as well as migration, invasion, and EMT of lung cancer cells in co-culture. M2 macrophage-derived interleukin 10 (IL-10) was investigated as a critical signaling molecule between M2 macrophage and lung cancer cells. We have also verified that the mechanism of (-)-Guaiol inhibiting the EMT process of lung cancer is related to the activation of IL-10-mediated signal transducer and activator of transcription 3 (STAT3). These results suggested that the suppressive effect role of (-)-Guaiol in M2 macrophage promoting EMT of lung cancer, which was associated with inhibition of IL-10 mediated STAT3 signaling pathway.

Pharmacological boosting of cGAS activation sensitizes chemotherapy by enhancing antitumor immunity.

Enhancing chemosensitivity is one of the largest unmet medical needs in cancer therapy. Cyclic GMP-AMP synthase (cGAS) connects genome instability caused by platinum-based chemotherapeutics to type I interferon (IFN) response. Here, by using a high-throughput small-molecule microarray-based screening of cGAS interacting compounds, we identify brivanib, known as a dual inhibitor of vascular endothelial growth factor receptor and fibroblast growth factor receptor, as a cGAS modulator. Brivanib markedly enhances cGAS-mediated type I IFN response in tumor cells treated with platinum. Mechanistically, brivanib directly targets cGAS and enhances its DNA binding affinity. Importantly, brivanib synergizes with cisplatin in tumor control by boosting CD8+ T cell response in a tumor-intrinsic cGAS-dependent manner, which is further validated by a patient-derived tumor-like cell clusters model. Taken together, our findings identify cGAS as an unprecedented target of brivanib and provide a rationale for the combination of brivanib with platinum-based chemotherapeutics in cancer treatment.

Combined clinical features and MRI parameters for the prediction of VEGFR2 in hepatocellular carcinoma patients.

Purpose: To develop a prediction model for estimating the expression of vascular endothelial growth factor receptor 2 (VEGFR2) in hepatocellular carcinoma (HCC) patients using clinical features and the contrast-enhanced MRI Liver Imaging Reporting and Data System (LI-RADS). Methods: A total of 206 HCC patients were subjected to preoperative contrast-enhanced MRI, radical resection, and VEGFR2 immunohistochemistry labeling. The intensity of VEGFR2 expression was used to split patients into either the positive group or the negative group. For continuous data, the Mann-Whitney U test was employed, and for categorical variables, the χ2 test was utilized. Results: VEGFR2-positivity was identified in 41.7% (86/206) of the patients. VEGFR2-positive HCCs were confirmed by higher serum alpha-fetoprotein (AFP) levels, larger tumor dimensions (either on MRI or upon final pathology), and a higher LI-RADS score (all p < 0.001). LI-RADS scores and AFP levels were independent predictors for high VEGFR2 expression. These two parameters were used to establish a VEGFR2-positive risk nomogram, which was validated to possess both good discrimination and calibration. The area under the curve was 0.830 (sensitivity 83.6%, specificity 72.5%) and the mean absolute error was 0.021. The threshold probabilities ranged between 0.07 and 0.95, and usage of the model contributed net benefits. Conclusion: A nomogram including clinical features and contrast-enhanced MRI parameters was developed and was demonstrably effective at predicting VEGFR2 expression in HCC patients.

The multifaceted functions of cGAS.

Pattern recognition receptors are critical for the sensing of pathogen-associated molecular patterns or danger-associated molecular patterns and subsequent mounting of innate immunity and shaping of adaptive immunity. The identification of 2'3'-cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) synthase (cGAS) as a major cytosolic DNA receptor is a milestone in the field of DNA sensing. The engagement of cGAS by double-stranded DNA from different origins, including invading pathogens, damaged mitochondria, ruptured micronuclei, and genomic DNA results in the generation of cGAMP and activation of stimulator of interferon genes, which thereby activates innate immunity mainly characterized by the activation of type I interferon response. In recent years, great progress has been made in understanding the subcellular localization and novel functions of cGAS. In this review, we particularly focus on summarizing the multifaceted roles of cGAS in regulating senescence, autophagy, cell stemness, apoptosis, angiogenesis, cell proliferation, antitumor effect, DNA replication, DNA damage repair, micronucleophagy, as well as cell metabolism.

Cytoplasmic PARP1 links the genome instability to the inhibition of antiviral immunity through PARylating cGAS.

Virus infection modulates both host immunity and host genomic stability. Poly(ADP-ribose) polymerase 1 (PARP1) is a key nuclear sensor of DNA damage, which maintains genomic integrity, and the successful application of PARP1 inhibitors for clinical anti-cancer therapy has lasted for decades. However, precisely how PARP1 gains access to cytoplasm and regulates antiviral immunity remains unknown. Here, we report that DNA virus induces a reactive nitrogen species (RNS)-dependent DNA damage and activates DNA-dependent protein kinase (DNA-PK). Activated DNA-PK phosphorylates PARP1 on Thr594, thus facilitating the cytoplasmic translocation of PARP1 to inhibit the antiviral immunity both in vitro and in vivo. Mechanistically, cytoplasmic PARP1 interacts with and directly PARylates cyclic GMP-AMP synthase (cGAS) on Asp191 to inhibit its DNA-binding ability. Together, our findings uncover an essential role of PARP1 in linking virus-induced genome instability with inhibition of host immunity, which is of relevance to cancer, autoinflammation, and other diseases.

Pan-Cancer Analysis of Glycolytic and Ketone Bodies Metabolic Genes: Implications for Response to Ketogenic Dietary Therapy.

BACKGROUND: The Warburg effect, also termed "aerobic glycolysis", is one of the most remarkable and ubiquitous metabolic characteristics exhibited by cancer cells, representing a potential vulnerability that might be targeted for tumor therapy. Ketogenic diets (KDs), composed of high-fat, moderate-protein and low carbohydrates, are aimed at targeting the Warburg effect for cancer treatment, which have recently gained considerable attention. However, the efficiency of KDs was inconsistent, and the genotypic contribution is still largely unknown. METHODS: The bulk RNA-seq data from The Cancer Genome Atlas (TCGA), single cell RNA sequencing (scRNA-seq), and microarray data from Gene Expression Omnibus (GEO) and Cancer Cell Line Encyclopedia (CCLE) were collected. A joint analysis of glycolysis and ketone bodies metabolism (KBM) pathway was performed across over 10,000 tumor samples and nearly 1,000 cancer cell lines. A series of bioinformatic approaches were combined to identify a metabolic subtype that may predict the response to ketogenic dietary therapy (KDT). Mouse xenografts were established to validate the predictive utility of our subtypes in response to KDT. RESULTS: We first provided a system-level view of the expression pattern and prognosis of the signature genes from glycolysis and KBM pathway across 33 cancer types. Analysis by joint stratification of glycolysis and KBM revealed four metabolic subtypes, which correlated extensively but diversely with clinical outcomes across cancers. The glycolytic subtypes may be driven by TP53 mutations, whereas the KB-metabolic subtypes may be mediated by CTNNB1 (ß-catenin) mutations. The glycolytic subtypes may have a better response to KDs compared to the other three subtypes. We preliminarily confirmed the idea by literature review and further performed a proof-of-concept experiment to validate the predictive value of the metabolic subtype in liver cancer xenografts. CONCLUSIONS: Our findings identified a metabolic subtype based on glycolysis and KBM that may serve as a promising biomarker to predict the clinical outcomes and therapeutic responses to KDT.

A Bioinformatic Analysis of Correlations between Polymeric Immunoglobulin Receptor (PIGR) and Liver Fibrosis Progression.

OBJECTIVE: This study is aimed at investigating the enriched functions of polymeric immunoglobulin receptor (PIGR) and its correlations with liver fibrosis stage. METHODS: PIGR mRNA expression in normal liver, liver fibrosis, hepatic stellate cells (HSCs), and hepatitis virus infection samples was calculated in Gene Expression Omnibus (GEO) and Oncomine databases. Enrichment analysis of PIGR-related genes was conducted in Metascape and Gene Set Enrichment Analysis (GSEA). Logistic model and ROC curve were performed to evaluate the correlations between pIgR and liver fibrosis. RESULTS: PIGR mRNA was upregulated in advanced liver fibrosis, cirrhosis compared to normal liver (all p < 0.05). PIGR mRNA was also overexpressed in activated HSCs compared to senescent HSCs, liver stem/progenitor cells, and reverted HSCs (all p < 0.05). Enrichment analysis revealed that PIGR-related genes involved in the defense response to virus and interferon (IFN) signaling. In GEO series, PIGR mRNA was also upregulated by hepatitis virus B, C, D, and E infection (all p < 0.05). After adjusting age and gender, multivariate logistic regression models revealed that high PIGR in the liver was a risk factor for liver fibrosis (OR = 82.2, p < 0.001). The area under curve (AUC), positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity of PIGR for liver fibrosis stage >2 were 0.84, 0.86, 0.7, 0.61, and 0.90. CONCLUSION: PIGR was correlated with liver fibrosis and might involve in hepatitis virus infection and HSC transdifferentiation.

Sensing of mycobacterial arabinogalactan by galectin-9 exacerbates mycobacterial infection.

Mycobacterial arabinogalactan (AG) is an essential cell wall component of mycobacteria and a frequent structural and bio-synthetical target for anti-tuberculosis (TB) drug development. Here, we report that mycobacterial AG is recognized by galectin-9 and exacerbates mycobacterial infection. Administration of AG-specific aptamers inhibits cellular infiltration caused by Mycobacterium tuberculosis (Mtb) or Mycobacterium bovis BCG, and moderately increases survival of Mtb-infected mice or Mycobacterium marinum-infected zebrafish. AG interacts with carbohydrate recognition domain (CRD) 2 of galectin-9 with high affinity, and galectin-9 associates with transforming growth factor ß-activated kinase 1 (TAK1) via CRD2 to trigger subsequent activation of extracellular signal-regulated kinase (ERK) as well as induction of the expression of matrix metalloproteinases (MMPs). Moreover, deletion of galectin-9 or inhibition of MMPs blocks AG-induced pathological impairments in the lung, and the AG-galectin-9 axis aggravates the process of Mtb infection in mice. These results demonstrate that AG is an important virulence factor of mycobacteria and galectin-9 is a novel receptor for Mtb and other mycobacteria, paving the way for the development of novel effective TB immune modulators.

Roles of APOBEC3 in hepatitis B virus (HBV) infection and hepatocarcinogenesis.

APOBEC3 (A3) cytidine deaminases inhibit hepatitis B virus (HBV) infection and play vital roles in maintaining a variety of biochemical processes, including the regulation of protein expression and innate immunity. Emerging evidence indicates that the deaminated deoxycytidine biochemical activity of A3 proteins in single-stranded DNA makes them a double-edged sword. These enzymes can cause cellular genetic mutations at replication forks or within transcription bubbles, depending on the physiological state of the cell and the phase of the cell cycle. Under pathological conditions, aberrant expression of A3 genes with improper deaminase activity regulation may threaten genomic stability and eventually lead to cancer development. This review attempted to summarize the antiviral activities and underlying mechanisms of A3 editing enzymes in HBV infections. Moreover, the correlations between A3 genes and hepatocarcinogenesis were also elucidated.

C8B in Complement and Coagulation Cascades Signaling Pathway is a predictor for Survival in HBV-Related Hepatocellular Carcinoma Patients.

OBJECTIVE: The role of the complement and coagulation cascades signaling pathway in the pathogenesis of cancers remains uncertain. This study aimed to investigate the associations between enriched differentially expressed genes (DEGs) in this pathway and hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients. MATERIALS AND METHODS: Clinical and gene expression data of the Gene Expression Omnibus (GEO) series profile GSE14520 were downloaded. The "Limma" package was used to screen the DEGs and the "clusterProfiler" package was used to identify the complement and coagulation cascades pathway and enriched significant genes. Cox regression analysis, the Kaplan-Meier method, and the nomogram model were used to address the correlations between significantly enriched DEGs in the complement and coagulation cascades pathway and HCC survival. RESULTS: A total of 220 HBV-related HCC patients were enrolled in this study. The complement and coagulation cascades pathway was significantly enriched by 37 DEGs (p-value < 0.05 and adjusted p-value < 0.05). Complement 8 beta chain (C8B) expression levels had protective effects on overall survival (OS) and recurrence-free survival (RFS) in HBV-related HCC patients. High levels of C8B contributed to favorable OS and RFS in this population (both p < 0.01), even after adjustment of clinicopathological characteristics including tumor node metastasis (TNM) staging, Barcelona Clinic liver cancer (BCLC) staging, gender, and fibrinogen beta chain (FGB) expression (all p < 0.05). CONCLUSION: C8B in the complement and coagulation cascades signaling pathway serves as a predictive candidate for survival in HBV-related HCC patients.

CGAS is a micronucleophagy receptor for the clearance of micronuclei.

Micronuclei are constantly considered as a marker of genome instability and very recently found to be a trigger of innate immune responses. An increased frequency of micronuclei is associated with many diseases, but the mechanism underlying the regulation of micronuclei homeostasis remains largely unknown. Here, we report that CGAS (cyclic GMP-AMP synthase), a known regulator of DNA sensing and DNA repair, reduces the abundance of micronuclei under genotoxic stress in an autophagy-dependent manner. CGAS accumulates in the autophagic machinery and directly interacts with MAP1LC3B/LC3B in a manner dependent upon its MAP1LC3-interacting region (LIR). Importantly, the interaction is essential for MAP1LC3 recruitment to micronuclei and subsequent clearance of micronuclei via autophagy (micronucleophagy) in response to genotoxic stress. Moreover, in contrast to its DNA sensing function to activate micronuclei-driven inflammation, CGAS-mediated micronucleophagy blunts the production of cyclic GMP-AMP (cGAMP) induced by genotoxic stress. We therefore conclude that CGAS is a receptor for the selective autophagic clearance of micronuclei and uncovered an unprecedented role of CGAS in micronuclei homeostasis to dampen innate immune surveillance.Abbreviations: ATG: autophagy-related; CGAS: cyclic GMP-AMP synthase; CQ: chloroquine; GABARAP: GABA type A receptor-associated protein; GFP: green fluorescent protein; LAMP1: lysosomal associated membrane protein 1; LAMP2: lysosomal associated membrane protein 2; LIR, MAP1LC3-interacting region; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; NDZ: nocodazole; STING1: stimulator of interferon response cGAMP interactor 1.

Hsa-circRNA-103809 Promotes Hepatocellular Carcinoma Development via MicroRNA-1270/PLAG1 Like Zinc Finger 2 Axis.

BACKGROUND: Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death in the worldwide. A great number of reports manifested that circular RNA hsa-circRNA-103809 (circRNA-103809) could work in several cancers. AIMS: This study aimed to explore the function and mechanism of circRNA-103809 in HCC. METHODS: Gene expressions were detected by quantitative real-time polymerase chain reaction. Colony formation, cell counting kit-8, transwell and wound healing assays were implemented to check the role of circRNA-103809 in HCC. Subcellular fractionation analysis was designed to figure out the cellular location of circRNA-103809. Luciferase reporter assay and RNA pull down assay were employed to verify the relationships among RNAs. RESULTS: CircRNA-103809 was highly expressed in HCC cell lines. After interfering circRNA-103809, the proliferation, migration, invasion and epithelial-to-mesenchymal transition process were all hindered in HCC cells. Significantly, circRNA-103809 competed with PLAG1 like zinc finger 2 (PLAGL2) for binding with microRNA-1270 (miR-1270), which formulated a competing endogenous RNA network in HCC. Thereafter, we verified the tumor-facilitating effect of circRNA-103809/miR-1270/PLAGL2 axis on biological behaviors of HCC cells. CONCLUSION: Hsa-circRNA-103809 promoted development of HCC via sequestering miR-1270 and up-regulating PLAGL2.

Regulatory T cell and activated natural killer cell infiltration in hepatocellular carcinoma: immune cell profiling using the CIBERSORT.

BACKGROUND: Hepatocellular carcinoma (HCC) is understood to be an immunogenic tumor caused by chronic liver disease. Emerging research has indicated close interaction between various immune cells and tumor cells. Immunophenotyping, which has shown potential predictive value for the prognosis of various human malignancies, might allow responsive and non-responsive patients to be identified based on the extent and distribution of immune cell infiltration. Several novel immunotherapeutic approaches have been trialed and have shown promising efficacy. However, the efficacy of immunotherapies in HCC is limited by several factors. This study aimed to investigate tumor-infiltrating immune cells in HCC. METHODS: Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) allows immune cell profiling analysis by deconvolution of gene expression microarray data. In this study, we analyzed the proportions of immune cells in 14 paired samples of HCC tissues obtained from GSE84402 in Gene Expression Omnibus (GEO) database. RESULTS: In the 14 paired samples, HCC tissues showed significant infiltration by regulatory T cells (Tregs), activated natural killer (NK) cells, and M0 macrophages (P<0.001, P=0.007 and P=0.001, respectively), which were validated in CIBERSORT with the P value set at ≤0.05. In four paired samples identified from those selected by CIBERSORT, HCC tissues were found to have significant Treg and activated NK cell infiltration compared to non-tumor tissues (P=0.007 and P=0.015, respectively). Additionally, Pearson correlation analysis revealed Tregs to be positively correlated with activated NK cells (Correlation coefficient =0.41). CONCLUSIONS: HCC tumor tissues were markedly infiltrated by Tregs and activated NK cells, which should be considered as candidate therapeutic targets in HCC multidisciplinary treatments.