The clinical significance of microRNAs (miRNAs) in intrahepatic cholangiocarcinoma (ICC) is unclear. The objective of this study is to examine the miRNA expression profiles and identify a miRNA signature for the prognosis of ICC. Using a custom microarray containing 1,094 probes, the miRNA expression profiles of 63 human ICCs and nine normal intrahepatic bile ducts (NIBD) were assessed. The miRNA signatures were established and their clinical significances in ICC were analyzed. The expression levels of some miRNAs were verified by quantitative real-time RT-PCR (qRT-PCR). Expression profile analysis showed 158 differentially expressed miRNAs between ICC and NIBD, with 77 up-regulated and 81 down-regulated miRNAs. From the 158 differentially expressed miRNAs, a 30-miRNA signature consisting of 10 up-regulated and 20 down-regulated miRNAs in ICC was established for distinguishing ICC from NIBD with 100% accuracy. A separate 3-miRNA signature was identified for predicting prognosis in ICC. Based on the 3-miRNA signature, a formula was constructed to compute a risk score for each patient. The patients with high-risk had significantly lower overall survival and disease-free survival than those with low-risk. The expression level of these three miRNAs detected by microarray was verified by qRT-PCR. Multivariate analysis indicated that the 3-miRNA signature was an independent prognostic predictor. In this study, a 30-miRNA signature for distinguishing ICC from NIBD, and a 3-miRNA signature for evaluating prognosis of ICC were established, which might be able to serve as biomarkers for prognosis of ICC. Further studies focusing on these miRNAs may shed light on the mechanisms associated with ICC pathogenesis and progression.

Background: Increased histone H3 phosphorylation is an essential regulatory mechanism for neoplastic cell transformation. We aimed to explore the role of histone H3 phosphorylation at serine10 (p-H3Ser10) in Epstein-Barr virus (EBV) latent membrane protein-1 (LMP1)-induced carcinogenesis of nasopharyngeal carcinoma (NPC). Methods: The expression of p-H3Ser10 was detected by the immunohistochemical analysis in NPC, chronic nasopharyngitis and normal nasopharynx tissues, and its correlation with LMP1 was analyzed in NPC tissues and cell lines. Using the small interfering RNA (siRNA)-H3 and histone H3 mutant (S10A), the effect of histone H3 Ser10 motif on LMP1-induced CNE1 cell proliferation, transformation and activator protein-1 (AP-1) activation were evaluated by CCK-8, focus-forming and reporter gene assay respectively. Mitogen- and stress-activated kinase 1 (MSK1) kinase activity and phosphorylation were detected by in vitro kinase assay and western blot. Using MSK1 inhibitor H89 or siRNA-MSK1, the regulatory role of MSK1 on histone H3 phosphorylation and AP-1 activation were analyzed. Results: Immunohistochemical analysis revealed that the expression of p-H3Ser10 was significantly higher in the poorly differentiated NPC tissues than that in chronic nasopharyngitis (p <0.05) and normal nasopharynx tissues (p <0.001). Moreover, high level of p-H3Ser10 was positively correlated with the expression of LMP1 in NPC tissues (χ ²=6.700, p =0.01; C=0.350) and cell lines. The knockdown and mutant (S10A) of histone H3 suppressed LMP1-induced CNE1 cell proliferation, foci formation and AP-1 activation. In addition, LMP1 could increase MSK1 kinase activity and phosphorylation. MSK1 inhibitor H89 or knockdown of MSK1 by siRNA blocked LMP1-induced phosphorylation of histone H3 at Ser10 and AP-1 activation. Conclusion: EBV-LMP1 can induce phosphorylation of histone H3 at Ser10 via MSK1. Increased phosphorylation of histone H3 at Ser10 is likely a crucial regulatory mechanism involved in LMP1-induced carcinogenesis of NPC.

Mitogen- and Stress-Activated Kinase 1 (MSK1) is a nuclear kinase that serves as active link between extracellular signals and the primary response of gene expression. However, the involvement of MSK1 in malignant transformation and cancer development is not well understood. In this study, we aimed to explore the role of MSK1 in Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1)-promoted carcinogenesis of nasopharyngeal carcinoma (NPC). The level of MSK1 phosphorylation at Thr581 was detected by the immunohistochemical analysis in NPC tissues and normal nasopharynx tissues, and its correlation with LMP1 was analyzed in NPC tissues and cell lines. Using MSK1 inhibitor H89 or small interfering RNA (siRNA)-MSK1, the effects of MSK1 on LMP1-promoted CNE1 cell proliferation and transformation were evaluated by CCK-8 assay, flow cytometry and focus-forming assay respectively. Furthermore, the regulatory role of MSK1-mediated histone H3 phosphorylation at Ser10 on the promoter activity and expression of Fra-1 or c-Jun was determined by reporter gene assay and western blotting analysis. Immunohistochemical analysis revealed that the level of MSK1 phosphorylation at Thr581 was significantly higher in the poorly differentiated NPC tissues than that in normal nasopharynx tissues (P < 0.001). Moreover, high level of phosphorylated MSK1 was positively correlated with the expression of LMP1 in NPC tissues (r = 0.393, P = 0.002) and cell lines. MSK1 inhibitor H89 or knockdown of MSK1 by siRNA dramatically suppressed LMP1-promoted CNE1 cell proliferation, which was associated with the induction of cell cycle arrest at G0/G1 phase. In addition, the anchorage-independent growth promoted by LMP1 was blocked in MSK1 knockdown cells. When the activity or expression of MSK1 was inhibited, LMP1-induced promoter activities of Fra-1 and c-Jun as well as their protein levels were greatly reduced. It was found that only H3 WT, but not mutant H3 S10A, dramatically increased LMP1 induction of Fra-1 and c-Jun genes compared with mock cells. Increased MSK1 activity is critically important for LMP1-promoted cell proliferation and transformation in NPC, which may be correlated with its induction of Fra-1 and c-Jun through phosphorylation of histone H3 at Ser10.

The intracellular pathway of Janus kinase/signal transducer and activator of transcription (JAK/STAT) and modification of nucleosome histone marks regulate the expression of proinflammatory mediators, playing an essential role in carcinogenesis, antiviral immunity and the interaction of host proteins with Herpesviral particles. The pathway has also been suggested to play a vital role in the clinical course of the acute infection caused by severe acute respiratory syndrome coronavirus type 2 (SARS‑CoV‑2; known as coronavirus infection‑2019), a novel human coronavirus initially identified in the central Chinese city Wuhan towards the end of 2019, which evolved into a pandemic affecting nearly two million people worldwide. The infection mainly manifests as fever, cough, myalgia and pulmonary involvement, while it also attacks multiple viscera, such as the liver. The pathogenesis is characterized by a cytokine storm, with an overproduction of proinflammatory mediators. Innate and adaptive host immunity against the viral pathogen is exerted by various effectors and is regulated by different signaling pathways notably the JAK/STAT. The elucidation of the underlying mechanism of the regulation of mediating factors expressed in the viral infection would assist diagnosis and antiviral targeting therapy, which will help overcome the infection caused by SARS‑CoV‑2.

Cyclin D1 (CCND1) plays a key role in cell cycle regulation. It is a well-established human oncogene which is frequently amplified or overexpressed in cancers. The association between CCND1 G870A polymorphism and cancer risk has been widely assessed. However, a definitive conclusion between CCND1 G870A polymorphism and risk of nasopharyngeal carcinoma (NPC) remains elusive. We firstly performed a hospital-based case-control study involving 165 NPC cases and 191 cancer-free controls in central-south China, and then conducted a meta-analysis with six case-control studies to evaluate the association between NPC risk and CCND1 G870A polymorphism. The case-control study found a significant association between CCND1 G870A polymorphism and NPC risk in various comparison models (AA vs. GG: OR = 2.300, 95% CI 1.089–4.857, p = 0.029; AG vs. GG: OR = 2.832, 95% CI 1.367–5.867, p = 0.005; AA/AG vs. GG: OR = 2.597, 95% CI 1.288–5.237, p = 0.008; AA vs. AG/GG: OR = 0.984, 95% CI 0.638–1.518, p = 0.944). Further meta-analysis showed that there was no significant association between CCND1 G870A polymorphism and NPC risk in overall analysis. In the stratified analysis by race, however, significant associations were only found in Caucasians (for the allele model A vs. G: OR = 0.75, 95% CI 0.59–0.97, p = 0.03; for the co-dominant model AA vs. GG: OR = 0.52, 95% CI 0.32–0.86, p = 0.01; for the dominant model AA/AG vs. GG: OR = 0.49, 95% CI 0.32–0.74, p<0.01; for the recessive model AA vs. AG/GG: OR = 0.90, 95% CI 0.61–1.34, p = 0.60). A significant association between CCND1 G870A polymorphism and NPC risk was found in the central-southern Chinese population. The meta-analysis indicated that CCND1 G870A polymorphism may contribute to the development of NPC in Caucasians.