[The Mechanism of Resveratrol on Acute T-Lymphocyte Leukemia through IL-7-Mediated JAK / STAT Signaling Pathway]

OBJECTIVE

To explore the roles and relative mechanism of resveratrol against T-ALL through detecting the signaling molecules in IL-7 and JAK/STAT pathway.

METHODS

In vitro experiments, Molt4 cells were divided into 3 groups, including the control group, the DMSO group and resveratrol-treated group (Res group). The control group cells without any treatment, the DMSO group cells treated with 0.05% DMSO for 48 hours, the Res group cells treated with 200 μmol/L resveratrol for 48 hours. In vivo experiments, female C57BL/6J mice (6-8 weeks) were randomly divided into the control group, the T-ALL model group (T-ALL group), and Res treatment group (Res group). The control group mice treated with 0.05% DMSO by intragastric treatment, the T-ALL group mice treated with 0.05% DMSO by intragastric treatment, and the Res group mice treated with 10 mg/ml resveratrol. Expression of IL-7, IL-7R and Pim1 mRNA in the cells and mice spleen tissues were detected by RT-qPCR. Cell proliferation ability was detected by CCK-8. The expression of JAK1, JAK3, STAT5, phosphorylated JAK1 (p-JAK1), phosphorylated JAK3 (p-JAK3), phosphorylated STAT5 (p-STAT5) and Pim1 were detected by Western blot. ELISA was used to detect the IL-7 and IL-7R in the cells and mice serum of each groups.

RESULTS

Resveratrol could inhibit the proliferation ability of Molt4 cells, decrease the relative levels of p-JAK1, p-JAK3, p-STAT5, Pim1 protein, and the expression levels of Pim1, IL-7 and IL-7R mRNA in cells and mice spleens, reduce the IL-7 and IL-7R in Molt4 cells and mice serum.

CONCLUSION

Resveratrol may inhibite IL-7-medicated JAK/STAT signaling pathway to reduce the expression of target protein Pim1 to further exert its anti-T-ALL effects.

[Expression Level of SOCS3 in Acute Lymphoblastic Leukemia Cells Affects the Cytotoxicity of NK Cells]

OBJECTIVE

To detect the expression level of suppressors of cytokine signaling 3 （SOCS3） in acute lymphoblastic leukemia (ALL), and to observe the effect of over-expresson of SOCS3 in Jurkat cells on the cytotoxicity of NK cells.

METHODS

The expression levels of SOCS3 mRNA in peripheral blood mononuclear cells of 20 children with ALL and 20 healthy children (normal control group) were detected by RT-PCR. The peripheral blood NK cells from healthy subjects were selected by immunomagnetic technique, and the purity was detected by flow cytometry. SOCS3 was overexpressed in Jurkat cells infected with lentivirus vector, and SOCS3 mRNA expression was detected by RT-PCR after lentivirus infection. The NK cells were co-cultured with the infected Jurkat, and LDH release method was used to detect the cytotoxicity of NK cells on the infected Jurkat cells. The concentrations of TNF-α and IFN-γ were determined by ELISA. The expression of NKG2D ligands MICA and MICB on the surface of Jurkat cells were detected by flow cytometry. Western blot was used to detect the effect of SOCS3 overexpression on STAT3 phosphorylation in Jurkat cells.

RESULTS

Compared with the control group, the mRNA expression of SOCS3 in the peripheral blood mononucleated cells of ALL children was significantly decreased. The purity of NK cells isolated by flow cytometry could reach more than 70%. The expression of SOCS3 mRNA in Jurkat cells increased significantly after lentivirus infection. Overexpression of SOCS3 in Jurkat cells significantly promoted the killing ability of NK cells and up-regulated the secretion of TNF-α and IFN-γ from NK cells. The results of flow cytometry showed that the expression of NKG2D ligands MICA and MICB on Jurkat cells increased significantly after SOCS3 overexpression. Western blot results showed that overexpression of SOCS3 significantly reduced the phosphorylation level of STAT3 protein in Jurkat cells.

CONCLUSION

SOCS3 mRNA expression was significantly decreased in ALL patients, and overexpression of SOCS3 may up-regulate the expression of MICA and MICB of NKG2D ligands on Jurkat cell surface through negative regulation of JAK/STAT signaling pathway, thereby promoting the cytotoxic function of NK cells.