The aberrant activation of Wnt signaling has been implicated in a variety of human cancers, including gastric cancer. Given the current hypothesis that cancer arises from cancer stem cells (CSCs), targeting the critical signaling pathways that support CSC self-renewal appears to be a useful approach for cancer therapy. Cell cycle and apoptosis regulator 1 (CCAR1) is a transcriptional coactivator which has been shown to be a component of Wnt/β-catenin signaling, and which plays an important role in transcriptional regulation by β-catenin. However, the function and clinical significance of CCAR1 in gastric cancer have not been elucidated. Here, we show that elevated CCAR1 nuclear expression correlates with the occurrence of gastric cancer. In addition, RNAi-mediated CCAR1 reduction not only suppressed the cell growth and increased apoptosis in AGS and MKN28 cells, but also reduced the migration and invasion ability of these cells. Furthermore, an in vivo xenograft assay revealed that the expression level of CCAR1 was critical for tumorigenesis. Our data demonstrates that CCAR1 contributes to carcinogenesis in gastric cancer and is required for the survival of gastric cancer cells. Moreover, CCAR1 may serve as a diagnostic marker and a potential therapeutic target.

Aberrant Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling is crucial to the development of gastric cancer. In this study, we examined the role of STAT3 in the expression and methylation of its targets in gastric cancer patients. Results from RNA sequencing identified an inverse correlation between the expression of STAT3 and GATA6 in 23 pairs of gastric cancer patient samples. We discovered that the expression of GATA6 is epigenetically silenced through promoter methylation in gastric cancer cell lines. Interestingly, the inhibition of STAT3 using a novel STAT3 inhibitor restored the expression of GATA6 and its targets, trefoil factors 1 and 2 (TFF1/2). Moreover, disruption of STAT3 binding to GATA6 promoter by small hairpin RNA restored GATA6 expression in AGS cells. A clinically significant correlation was also observed between the expression of GATA6 and TFF1/2 among tissue samples from 60 gastric cancer patients. Finally, bisulfite pyrosequencing revealed GATA6 methylation in 65% (39/60) of the patients, and those with higher GATA6 methylation tended to have shorter overall survival. In conclusion, we demonstrated that aberrant JAK/STAT signaling suppresses TFF1/2 partially through the epigenetic silencing of GATA6. Therapeutic intervention of STAT3 in reversing the epigenetic status of GATA6 could benefit the treatment of gastric cancer and is worthy of further investigation.

Gastric cancer (GC) is among the most treatment-refractory epithelial malignancies. Aberrant activation of Wnt/β-catenin-signaling has been implicated in a variety of human cancers, including gastric cancer. Here we report that the elevated expression of lymphoid enhancer binding factor 1 (Lef1) is associated with the TNM (tumor– node–metastasis) stage of gastric cancer. Subsequently, 2,4-diamino-quinazoline (2,4-DAQ), a selective inhibitor of Lef1, was identified to suppress the expression of Wnt/β-catenin target genes such as AXIN2, MYC and LGR5 and result in the suppression of gastric cancer cell growth through the apoptotic pathway. The 2,4-DAQ also exhibited an inhibitory effect on the migration/invasion of gastric cancer cells. Importantly, the treatment of human gastric tumor xenograft with 2,4-DAQ suppressed tumor growth in a nude mouse model. Furthermore, 2,4-DAQ appears effective on patient-derived organoids (PDOs). Transcriptome sequencing analysis also revealed that 2,4-DAQ are more effective on the gastric cancers that exhibit higher expression levels of Wnt-signaling pathway-related genes than their adjacent normal gastric tissues.

The real-world benefits of direct-acting antiviral (DAA)-induced sustained virologic response (SVR) on the de novo occurrence and progression of esophageal varices (EV) remain unclear in patients with hepatitis C virus (HCV)-related liver cirrhosis (LC). This is a retrospective cohort study evaluating all patients with Child-Pugh class A HCV-related LC during 2013 to 2020 in the Chang Gung Medical System. A total of 215 patients fit the inclusion criteria and were enrolled. Of them, 132 (61.4%) patients achieved DAA induced-SVR and 83 (38.6%) did not receive anti-viral treatment. During a median follow-up of 18.4 (interquartile range, 10.1–30.9) months, the 2-year incidence of de novo EV occurrence was 8 (7.0%) in the SVR group and 7 (12.7%) in the treatment-naïve group. Compared to the treatment-naïve group, the SVR group was associated with a significantly lower incidence of EV occurrence (adjusted hazard ratio [aHR]: 0.47, p = 0.030) and a significantly lower incidence of EV progression (aHR: 0.55, p = 0.033). The risk of EV progression was strongly correlated with the presence of baseline EV (p < 0.001). To the best of our knowledge, this is the first study to demonstrate that DAA-induced SVR is associated with decreased risk of de novo EV occurrence and progression in the real world.

The ongoing COVID-19 pandemic, caused by SARS-CoV-2, continues to pose significant global health challenges. The results demonstrated that GB-2 at 200 μg/mL effectively increased the population of 293T-ACE2 cells with low RBD binding for both SARS-CoV-2 Omicron EG.5.1 and HV.1 variants by dual-color flow cytometry, indicating its ability to inhibit virus attachment. Further investigation revealed that (+)-catechin at 25 and 50 μg/mL did not significantly alter the ACE2–RBD interaction for the EG.5.1 variant. In contrast, theaflavin showed inhibitory effects at both 25 and 50 μg/mL for EG.5.1, while only the higher concentration was effective for HV.1. Notably, theaflavin 3-gallate exhibited a potent inhibition of ACE2–RBD binding for both variants at both concentrations tested. Molecular docking studies provided insight into the binding mechanisms of theaflavin and theaflavin 3-gallate with the RBD of EG.5.1 and HV.1 variants. Both compounds showed favorable docking scores, with theaflavin 3-gallate demonstrating slightly lower scores (−8 kcal/mol) compared to theaflavin (−7 kcal/mol) for both variants. These results suggest stable interactions between the compounds and key residues in the RBD, potentially explaining their inhibitory effects on virus attachment. In conclusion, GB-2, theaflavin, and theaflavin 3-gallate demonstrate significant potential as inhibitors of the ACE2–RBD interaction in Omicron variants, highlighting their therapeutic promise against COVID-19. However, these findings are primarily based on computational and in vitro studies, necessitating further in vivo research and clinical trials to confirm their efficacy and safety in humans.

Gastric cancer (GC) remains a major public health concern both in Taiwan and worldwide. While advances in public health have reduced its incidence rate, clinical outcomes of advanced GC remain suboptimal with current standard therapy. The Wnt/β-catenin signaling pathway is frequently up-regulated in GC, promoting tumor progression. This study investigated the anti-tumor effects of PKF118-310, a small molecule inhibitor of the β-catenin-TCF/LEF interaction, in GC cell lines and patient-derived models. GC cell lines and immortalized gastric epithelial GES-1 cells were treated with PKF118-310. Effects on proliferation, cell cycle, apoptosis, migration, invasion, and colony formation were assessed. Patient-derived organoids (PDOs) and xenograft (PDX) models were established to evaluate PKF118-310 efficacy. Tcf7 gene expression was analyzed via transcriptome sequencing, and tumor growth was monitored in vivo. PKF118-310 significantly inhibited GC cell proliferation, migration, invasion, and colony formation in a dose- and time-dependent manner, with minimal toxicity to GES-1 cells. It induced G1-phase cell cycle arrest, apoptosis, and down-regulation of Wnt/β-catenin signaling target genes and cancer stem cell (CSC) markers. In PDOs, Tcf7 gene expression correlated with PKF118-310 sensitivity. In PDX models, PKF118-310 reduced tumor growth without affecting body weight. PKF118-310 exhibits potent anti-tumor effects in GC by inhibiting the Wnt/β-catenin signaling pathway, reducing tumor growth, and targeting CSCs. These findings suggest PKF118-310 as a promising therapeutic candidate for GC treatment.