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RNA modification includes four main types, N6-methyladenosine, N1- methyladenosine, alternative polyadenylation (APA), and adenosine-to-inosine (A-to-I) RNA editing, involving 41 enzymes that serve as "writers", "readers" and "erasers". By collecting RNA modifying enzyme information in 1759 hepatobiliary malignancy (HBM) samples from 11 datasets, an RNA modification HBM Score (RH_score) was established based on unsupervised cluster analysis of RNA modification-associated differentially expressed genes (DEGs). We identified the imbalanced expression of 41 RNA modification enzymes in HBM, which was scientifically categorized into two groups: RH_Score high and RH_Score low. A high RH_Score was associated with a worse prognosis and more immature immune cells in the tumor microenvironment (TME), while a low RH_Score was associated with a better prognosis and more mature immune cells in the TME. Further analysis using single-cell databases showed that the high RH_Score was immune exhaustion in the TME. RH_Score was involved in transcriptional regulation and post-transcriptional events in HBM. Additionally, resistant and sensitive drugs were selected based on RNA modification, and anti-PD-L1 therapy responded better with low RH_Score. In conclusion, our study comprehensively analyzes RNA modification in HBM, which induces TME changes and transcriptional and posttranscriptional events, implying potential guiding significance in prognosis prediction and treatment options. [ABSTRACT FROM AUTHOR]

Objective: Protein convertase subtilisin/Kexin type 9 (PCSK9) has been found to be closely associated with the occurrence and development of numerous tumors. However, the precise role of PCSK9 and its relationship to the development of hepatocellular carcinoma (HCC) remain largely unknown. This study aimed to clarify these issues. Methods: The expression levels of PCSK9 in HCC tissues and HCC cell lines were determined by the quantitative reverse transcription polymerase chain reaction, Western blot, and immunohistochemical analyses, and the effects of PCSK9 expression on HCC cell biological traits were investigated by overexpressing and downregulating PCSK9 expression in vivo and in vitro. Additionally, the mechanism by which PCSK9 mediated dissociation of glutathione S-transferase Pi 1 (GSTP1) dimers and phosphorylation of the Jun N-terminal kinase (JNK) pathway components were investigated. Results: PCSK9 expression levels were significantly lower in HCC tissues than in adjacent non-tumor samples. In vivo and in vitro experiments suggested that PCSK9 inhibited HCC cell proliferation and metastasis. Further analysis showed that PCSK9 interacted with GSTP1 and promoted GSTP1 dimer dissociation and JNK signaling pathway inactivation in HCC cells. Moreover, the relationships between PCSK9 protein expressions and clinical outcomes were investigated. The PCSK9-lo group displayed a significantly shorter overall survival (OS; median OS: 64.2 months vs. 83.2 months; log-rank statistic: 4.237; P = 0.04) and recurrencefree survival (RFS; median RFS: 26.5 months vs. 46.6 months; log-rank statistic: 10.498; P = 0.001) time than the PCSK9-hi group. Conclusions: PCSK9 inhibited HCC cell proliferation, cell cycle progression, and apoptosis by interacting with GSTP1 and suppressing JNK signaling, suggesting that PCSK9 might act as a tumor suppressor and be a therapeutic target in HCC patients. [ABSTRACT FROM AUTHOR]

Developing predictive biomarkers that can detect the tipping point before metastasis of hepatocellular carcinoma (HCC), is critical to prevent further irreversible deterioration. To discover such early-warning signals or biomarkers of pulmonary metastasis in HCC, we analyse time-series gene expression data in spontaneous pulmonary metastasis mice HCCLM3-RFP model with our dynamic network biomarker (DNB) method, and identify CALML3 as a core DNB member. All experimental results of gain-of-function and loss-offunction studies show that CALML3 could indicate metastasis initiation and act as a suppressor of metastasis. We also reveal the biological role of CALML3 in metastasis initiation at a network level, including proximal regulation and cascading influences in dysfunctional pathways. Our further experiments and clinical samples show that DNB with CALML3 reduced pulmonary metastasis in liver cancer. Actually, loss of CALML3 predicts shorter overall and relapse-free survival in postoperative HCC patients, thus providing a prognostic biomarker and therapy target in HCC. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) develops in a complex microenvironment characterized by chronic inflammation. In recent years, cholesterol metabolic abnormalities have been implicated the importance in cancer cell physiology. This study was designed to investigate the relationship between inflammation and cholesterol accumulation in HCC cells. Methods: Human HCC cells HepG2 and Huh7 were cultured and stimulated with lipopolysaccharide (LPS) for 24 h. The changes of HCC cells related to cholesterol metabolism including intracellular cholesterol concentrations, cholesterol uptake, and the expression of cholesterol-related genes 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), LDL receptor (LDLR), sterol regulatory element-binding transcription factor 2 (SREBF2), and proprotein convertase subtilisin/kexin 9 (PCSK9) were comparatively analyzed. Simultaneously, the effects of nuclear factorkappa B (NF-κB) signaling pathway on cholesterol metabolism were clarified by knocking-down of nuclear factor kappa-B kinase subunit alpha (IKKα) and TGF-beta-activated kinase 1 and MAP3K7-binding protein 3 (TAB3) via RNAi and microRNA (miR)-195. Subsequently, the roles of cholesterol accumulation in LPS induced pro-inflammatory effects were further investigated. Results: Pro-inflammatory factor LPS significantly increased intracellular cholesterol accumulation by upregulating the expression of HMGCR, LDLR, and SREBF2, while downregulating the expression of PCSK9. These effects were revealed to depend on NF-κB signaling pathway by knocking-down and overexpression of IKKα and TAB3. Additionally, miR-195, a regulator directly targeting IKKα and TAB3, blocked the effects of cholesterol accumulation, further supporting the critical role of pro-inflammation NF-κB signaling in regulating cholesterol accumulation. Intriguingly, the accumulation of cholesterol conversely exerted an augmented pro-inflammation effects by further activating NF-κB signaling pathway. Conclusions: These results indicated that pro-inflammation effects of NF-κB signaling could be augmented by a positive feedback via enhancing the cholesterol accumulation in liver cancer cells. [ABSTRACT FROM AUTHOR]

Background: Histoplasmosis is a common opportunistic fungal infection that is observed almost exclusively in immunodeficient patients, especially those with AIDS. Immunocompetent individuals that suffer from histoplasmosis are rarely reported, especially those with disseminated lesions, such as disseminated histoplasmosis. The observation of disseminated histoplasmosis with prominent gastrointestinal involvement, no respiratory symptoms (which is presumed to be the portal of infection), gastrointestinal pathological changes, and minor digestive system disorders make this case study exceedingly rare. Case presentation: We report the case of a 33-year-old immunocompetent male who presented with fever and weight loss. Based on investigations, the patient showed pancytopenia, hepatosplenomegaly, bone marrow involvement and marked colonic involvement. Finally, disseminated histoplasmosis was diagnosed and confirmed by stained smears of fine needle aspirates and biopsy from lesions in the bone marrow and colon. The patient showed appreciable regression of lesions following prompt treatment with amphotericin B deoxycholate, and was treated thereafter with oral itraconazole following discharge from hospital. Conclusion: Disseminated histoplasmosis could be underestimated in immunocompetent patients. A high degree of clinical suspicion is essential in both immunocompromised and immunocompetent patients, regardless of pulmonary symptoms, and whether in endemic or non-endemic areas. Early and accurate diagnosis is extremely important for the appropriate treatment of infection and to improve disease outcome. [ABSTRACT FROM AUTHOR]