Research Progress of Regulatory T Cells in the Pathogenesis of Multiple Myeloma --Review / 中国实验血液学杂志

The multiple myeloma (MM), the second most common hematologic malignancy, is malignant proliferative disease of plasma cells. Although the application of many targeted drugs has significantly prolonged the survival time of MM patients, it is still an incurable disease. In recent years, the immunosuppression caused by interaction between tumor microenvironment(TME) and tumor cells has attracted people's attention gradually. As a kind of immunosuppressive cells in TME, regulatory T cells (Treg) play an important role in the progress of MM. Treg is related to the proliferation and metastasis of tumors, and can lead to the progress of MM by promoting the angiogenesis and generating immunosuppressive TME. In this review, we briefly summarized the latest research progress on the impact of Treg on the pathogenesis of MM.

Inhibitory Effect of PKC412 Against Human Acute Leukemia Cell Line HL-60 Cells / 中国实验血液学杂志

OBJECTIVE@#To explore the effects and mechanisms of PKC412 inhibitor on proliferation and apoptosis of HL-60 cell line.@*METHODS@#CCK-8 assay was used to detect the effect of PKC412 on the proliferation of HL-60 cells at different concentrations; Wright-Giemsa staining was used to estimated the effect of PKC412 on the apoptosis of HL-60 cells; the mRNA expression of BCL-2 and P53 genes was detected by qRT-PCR, the expression of BCL-2 and P53 proteins was detected by Western blot. HL-60 cells were injected into mouse caudal vein to construct acute myeloid leukemia model, PKC412 was administered to tail vein for 31.25 nmol/kg, normal saline was injected into the same site of the mice as control group, and the inhibitory effect of PKC412 on HL-60 cells in mice was observed. ELISA assay was used to detect the effect of PKC412 on the inflammatory factors of TNF-α and TGF-β in tumor mice.@*RESULTS@#PKC412 could inhibit the proliferation of HL-60 cell, which was in a dose dependent manner(r=0.9973) (IC50 was 0.31 μmol/L), and induce apoptosis of HL-60 cells. After HL-60 cell was treated by PKC412 for 48 h the expression of BCL-2 gene was down regulated(0.417±0.044 vs 0.933±0.033, t=9.347, P0.05) as compared with control group. And the expression of BCL-2 protein was decreased, while the expression of P53 protein was increased. PKC412 could inhibited the growth of HL-60 tumor cells in vivo, the survival rate of mice after administration was 50% and the weight was increased as compared with that in control group(18.02±0.403 g vs 16.44±0.562 g, t=2.272, P=0.0356). The secretion of TNF-α and TGF-β cytokine in serum and spleen cells in PKC412 group was significantly lower than that in control group (P<0.05).@*CONCLUSION@#PKC412 can induce apoptosis of HL-60 cells by inhibiting the expression level of BCL-2 gene, PKC412 administration in vivo can inhibit the growth of the tumors.