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Objective(s): Exhausted CD8+ T-cells over-express immune checkpoint receptors (ICRs), which interact with their ligands on malignant cells. However, some ICRs have been reported to be expressed on both T-cells and tumor cells, including V-domain immunoglobulin suppressor of T cell activation (VISTA), Galectin-9, and T-cell immunoglobulin mucin-3 (TIM-3). We aimed to evaluate the mRNA expression of VISTA, Galectin-9, and TIM-3 on CD8+ T-cells and leukemic cells in B-cell acute lymphoblastic leukemia (B-ALL).Materials and Methods: Samples were obtained from 26 untreated B-ALL patients and 25 control subjects. CD8+ T-cells were isolated using Magnetic Activated Cell Sorting (MACS). Relative gene expression was then evaluated by qRT-PCR with specific primers for VISTA, Galectin-9, and TIM-3. Also, the mRNA expression profile and clinical data of 154 B-ALL patients were obtained from the TARGET.Results: mRNA expression of Galectin-9 on CD8+ T-cells in B-ALL patients was significantly lower than those in the control group (P=0.043), while VISTA expression was not significantly different between the two study groups (P=0.259). Besides, TIM-3 expression was significantly higher in B-ALL patients than in the control group (P

Objective(s): Frizzled-7, the most common receptor of the Wnt signaling pathway, was significantly over-expressed in gastric (GC) and colorectal (CRC) cancers and stimulated tumorigenesis. The extracellular domain of Fzd7 (sFzd7) as a decoy receptor, could competitively bound with ligands and antagonize the interaction between Fzd7 receptors and Wnt ligands. Materials and Methods: We expressed and purified the extracellular region of Fzd7 including cysteine-rich domain (33 aa–185 aa) from Escherichia coli by chromatography. The effect of sFzd7 was evaluated on AGS gastric and SW480 colon cancer cell lines expressing high levels of Fzd7 receptor. Accordingly, cell viability and apoptosis were measured using MTT and flow cytometry assays, respectively. Real-Time PCR determined the relative expression of the β-catenin and cyclin-D1 genes. Results: After three days of treatment with sFzd7, the viability of AGS and SW480 cell lines was decreased in a dose-dependent manner. In addition, sFzd7 at concentrations of 10 and 20 ug/ml increased the rate of apoptosis. Especially at the concentration of 20 ug/ml, the apoptosis rate was remarkably high in AGS (P-value= 0.003) and SW480 cells (P-value= 0.0007). Finally, the expressions of β-catenin (P-value= 0.01) and cyclin-D1 (P-value= 0.02) were obviously decreased in SW480 cells. The same results were obtained in AGS cells, although not statistically significant. Conclusion: sFzd7 decoy receptor inhibits tumor cell progression by attenuating the Wnt pathway through inhibiting Fzd7 receptors and Wnt ligand interaction. Hence, sFzd7 can be proposed as a candidate therapy for GC and CRC cells with high levels of Fzd7 expression.