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Sall4 is a novel oncogene found upregulated in several malignancies including colon cancer. However, its upstream regulatory miRNA is still undefined. miR-219-5p is regarded as a tumor-related miRNA in cancer research. Nevertheless, its actual role of whether inhibiting or promoting tumorigenesis is unclear in colon cancer. Potential interaction between Sall4 and miR-219-5p is predicted by TargetScan. CCK-8 test was used for evaluation of cell proliferation and cell survival rates. Western blot analysis and real-time PCR were applied for detection of target molecules. Luciferase assay was a direct confirmation of mutual interaction. Wound healing assay and transwell assay were conducted for cell migration and invasion tests. Flow cytometry was used for cell apoptosis analysis. Tissue specimens and cell lines were explored for miR-219-5p inhibition on colon cancer proliferation, migration, invasion, apoptosis and drug resistance by targeting Sall4. The results show that miR-219-5p inhibited carcinogenesis of colon cancer by targeting oncogene Sall4.

The most common cause of gastric cancer is infection with helicobacter pylori (HP), but the associated molecular mechanism is not well understood. In the present study, we found a marked increase in the expression of B7-H1, a member of the B7 co-stimulatory family of molecules that bind to programmed death-1 (PD-1) and play a critical immunoregulatory role in the cell-mediated immune response, in HP-positive gastric cancer tissue. Infection of cultured gastric cancer cells with HP promoted B7-H1 expression and inhibited miR-152 and miR-200b expression. We further demonstrated that these two miRNAs targeted B7-H1 mRNA and suppressed B7-H1 expression in gastric cancer cells. Finally, B7-H1 expression was found to correlate with miR-152 and miR-200b levels in gastric tumor tissues from human patients. Our findings suggest a novel mechanism by which HP infection promotes gastric cancer and also suggest potential targets, i.e., miR-152 and miR-200b, for the prevention and treatment of gastric cancer.

Osteosarcoma (OS) is a rare malignant bone tumor that commonly occurs in children and adolescents and causes pain and swelling of the long bones of the legs and arms. Long non-coding RNA (lncRNA) and micro (mi)RNA-101 are important in the initialization and progression of OS. However, the mechanism underlying the role of the lncRNA and miRNA-101 in OS remains to be fully elucidated. In the present study, through reverse transcription-quantitative polymerase chain reaction analysis, it was first found that the lncRNA SNHG1 was upregulated and miRNA-101-3p was downregulated in OS tissues and cell lines. Second, the knockdown of lncRNA SNHG1 induced cell apoptosis and maintained the cell cycle at the G0/G1 phase, which decreased the overall cell viability. Furthermore, according to a dual-luciferase assay and western blot analysis, miRNA-101-3p was found to be a target of the lncRNA SNHG1 in OS, which further regulated the expression of Rho-associated coiled-coil-containing protein kinase 1 (ROCK1). It was found that the phosphoinositide 3-kinase/ATK pathway was inactivated and that epithelial-mesenchymal transition was activated in OS cell lines with overexpression of the lncRNA SNHG1. Taken together, in OS cell lines, the lncRNA SNHG1 acted as an oncogene, and miRNA-101-3p was considered a tumor suppressor. The lncRNA SNHG1 promoted OS cell proliferation, migration and invasion by downregulating the expression of miRNA-101-3p, which enhanced the expression of ROCK1.

A schematic representation of MoS2 nanosheet synthesis and its photothermal-triggered drug delivery application.

Summary Background Serum hepatitis B virus (HBV) RNA is a novel biomarker for evaluating treatment response. Detailed information regarding serum HBV RNA kinetics during treatment with nucleos(t)ide analogues (NAs) is limited. Aims To ascertain serum HBV RNA kinetics during long‐term NA treatment and identify associated factors. Methods We enrolled 76 HBeAg‐positive chronic hepatitis B patients receiving NA from randomised controlled trials. Laboratory assays were undertaken every 3 months. Factors associated with serum HBV RNA kinetics were identified by generalised estimating equations. Results Baseline serum HBV RNA was 8.5 ± 1.0 log10 copies/mL. Decline in serum HBV RNA during NA therapy was biphasic: the first phase (HBV DNA detectable) had a fast decrease (median slope, −0.207 log10 copies/mL/month) and was followed by a second phase (HBV DNA undetectable) with slow decrease (median slope, −0.071 log10 copies/mL/month). In the first phase, factors independently associated with lower initial serum HBV RNA were male sex (OR, 0.685, P = 0.044), low baseline HBsAg (OR, 0.525, P = 0.001) and rapid virological response (RVR) (OR, 0.624, P = 0.031). In the second phase, only RVR was independently associated with serum HBV RNA kinetics, including its lower initial level (OR, 0.694, P = 0.043) and greater decline (OR, 0.966, P = 0.002). Based on viral dynamics, time needed to achieve undetectable serum HBV RNA from baseline was 43.56 (IQR: 29.49‐66.40) months. Conclusion RVR was a significant determinant for biphasic decline in serum HBV RNA during NA treatment, which significantly influenced the treatment duration required to achieve undetectable serum HBV RNA.

BackgroundNasopharyngeal carcinoma (NPC) is primarily caused by the Epstein-Barr virus (EBV) infection in NPC endemic areas. EBNA1 is an EBV-encoded nuclear antigen, which plays a critical role in the maintenance and replication of EBV genome. However, the mechanisms of EBNA1-promoted NPC immune escape are unknown. Regulatory T (Treg) cells are among the key regulators in restraining antitumor responses. However, the mechanisms of accumulation of Treg cells in NPC have not been defined. This study attempted to identify the detailed mechanisms of EBNA1 functions as a tumor accelerator to promote NPC immune escape by enhancing chemoattraction of Treg cells.MethodsmRNA profiles were determined by next-generation sequencing in NPC cells. In vitro and in vivo assays were performed to analyze the role of EBNA1 in regulation of recruitment of Treg cells. Colocation and coimmunoprecipitation analyzes were used to identify the SMAD3/c-JUN complex. Chromatin immunoprecipitation assay and dual luciferase reporter assays were designed to demonstrate c-JUN binding to miR-200a promoter and miR-200a targeting to CXCL12 3’Untranslated Regions. The hepatocellular carcinoma models were designed to demonstrate universality of the CXCL12-CXCR4-Treg axis in promoting immune evasion of various tumors.ResultA novel molecular mechanism was identified that involves EBV-EBNA1-stimulated chemotactic migration of Treg cells toward NPC microenvironment by upregulation of the transforming growth factor-β1 (TGFβ1)-SMAD3-PI3K-AKT-c-JUN-CXCL12-CXCR4 axis and downregulation of miR-200a. EBV-EBNA1 promotes the chemoattraction of Treg cells by governing the protein–protein interactions of the SMAD3/c-JUN complex in a TGFβ1-dependent manner in vitro and in vivo. TGFβ1 suppresses miR-200a by enhancing the SMAD3/c-JUN complex. miR-200a negatively regulates the CXCL12 chemokine by direct targeting of the CXCL12 3’UTR region. However, CXCL12 acts as the target gene of miR-200a and as an inhibitor of miR-200a transcription, and inhibition of miR-200a by CXCL12 is mediated by c-JUN, which directly binds to the miR-200a promoter and forms a c-JUN-miR-200a-CXCL12-c-JUN feedback loop. In addition, enhanced CXCL12 efficiently attracts CXCR4-positive Treg cells to remodel an immunosuppressive microenvironment.ConclusionsEBV-EBNA1 promotes chemotactic migration of Treg cells via the TGFβ1-SMAD3-PI3K-AKT-c-JUN-miR-200a-CXCL12-CXCR4 axis in the NPC microenvironment. These results suggest that EBV-EBNA1 may serve as a potential therapeutic target to reshape the NPC microenvironment.