ABSTRACT
OBJECTIVE@#To investigate the regulatory effects of Olaparib on natural killer cell activating receptor (NKG2D) ligands expression on human acute myeloid leukemia (AML) cell line HL-60, and to explore the molecular mechanism of Olaparib on HL-60 cells.@*METHODS@#After HL-60 cells in logarithmic growth phase were treated with Olaparib at different concentrations for different times (24, 48 h), the expression of NKG2D ligand on the surface of HL-60 cells was detected by flow cytometry. Western blot was used to dectect the expression of ERK expression in HL-60 cells. The killing effect of NK cells to HL-60 cells was detected by CFSE/PI method.@*RESULTS@#10 μmol/L Olaparib could upregulate the expression of NKG2D ligand on the surface of HL-60 cell at 24 and 48 hours, while 5 μmol/L Olaparib could induce up-regulation of the expression of ULBP-2 and ULBP-3 at 48 hours. Western blot analysis showed that ERK phosphorylation of HL-60 cells was enhanced after treating with Olaparib. The killing effect of NK cells to HL-60 cells could be enhanced by Olaparib, however, ERK inhibitor could suppress the killing effect of NK cells to HL-60 cells.@*CONCLUSION@#Olaparib can upregulate NKG2D ligands expression on the surface of HL-60 cells and enhance the cytotoxicity of NK cell to HL-60 cells. The mechanism may be related to Olaparib promoting ERK phosphorylation expression.
Subject(s)
Humans , Cell Line, Tumor , Cytotoxicity, Immunologic , HL-60 Cells , Histocompatibility Antigens Class I , Ligands , NK Cell Lectin-Like Receptor Subfamily K , Phthalazines , Piperazines , Poly(ADP-ribose) Polymerase InhibitorsABSTRACT
Neutrophils in the tumor microenvironment have anti-tumorigenic (N1) or pro-tumor igenic (N2) functions.N1 neutrophils are manipulated to have cytotoxicity against tumors;N2 neutrophils can lead to the tumorigenesis,tumor growth,metastasis and tumor angiogenesis by secreting neutrophil elastase,matrix metalloproteinases,cytokines and chemokines.This review summarizes the biological characteristics of N1 and N2 neutrophils in tumor immunology.
ABSTRACT
<p><b>OBJECTIVE</b>To analyze the cloning result of CD40 mutant from RPMI8226 cells, a multiple myeloma (MM) cell line, and study the change of the expressions of costimulatory molecules and the apoptosis of RPMI8226 cells after activated with CD40.</p><p><b>METHODS</b>CD40 gene mutant in RPMI8226 cell was detected by RT-PCR and DNA sequencing. The cell lines were cultured with sCD40L, L929/CD40L, soluble 5C11 (an anti-CD40 mAb) plate-bound 5C11 and their respective controls. Their growth curves, change of phenotypes and cell cycles were detected. The signalosome of CD40 on RPMI8226 cells were analyzed with laser scanning confocal microscope.</p><p><b>RESULTS</b>There was a single base substitution (TCA-->TTA) in the open reading frame of CD40 from RPMI8226 cells, resulting in the conversion of a amino acid (Ser124Leu). Only plate-bound antibody could inhibit RPMI8226 cell proliferation [(2.5 +/- 0.6) x 10(5) vs (7.8 +/- 1.2) x 10(5), P <0.05] and cause G1 arrested [(58.0 +/- 3.6)% vs (42.0 +/- 2.3)%, P <0.05]. muCD40 was translocated to CD40 signalosome while CD40 activated.</p><p><b>CONCLUSION</b>The mutated CD40 in RPMI8226 cell might decrease its affinity to CD40L, leading to the disorder of CD40 signal.</p>