PARP inhibitor re‑sensitizes Adriamycin resistant leukemia cells through DNA damage and apoptosis.

Resistance to Adriamycin (ADR) is an increasing problem in the treatment of leukemia and the development of novel therapeutic strategies is becoming increasingly important. Olaparib is a poly (adenosine diphosphate‑ribose) polymerase (PARP) 1 inhibitor, which has promising antitumor activity in patients with metastatic breast cancer and germline BRCA mutations. Previously published studies have indicated that Olaparib is able to overcome drug resistance in cancer; however, its underlying mechanism of action is yet to be elucidated.

Potentiation of arsenic trioxide-induced apoptosis by 8-bromo-7-methoxychrysin in human leukemia cells involves depletion of intracellular reduced glutathione.

The novel chrysin analog 8-bromo-7-methoxychrysin (BrMC) has been reported to induce apoptosis of various cancer cell lines. Arsenic trioxide (ATO) treatment induces clinical remission in acute promyelocytic leukemia patients. The combination of ATO with other agents has been shown to improve therapeutic effectiveness in vitro and in vivo.

[Apoptosis-inducing Effect of 8-Bromo-7-Methoxychrysin on K562 cells].

This study was purposed to investigate the apoptosis-inducing effect of 8-bromo-7-methoxychrysin (BrMChR) on leukemia K562 cells as well as the variation of caspase-3 activity and phosphorylated Akt (p-Akt) expression of K562 cells during the process of apoptosis. MTT assay was used to determine the inhibitory effect of BrMChR on proliferation of K562 cells. Cell apoptosis was assayed by AO/EB staining under fluorescent microscope and flow cytometry with Annexin V-FITC/PI staining.

[The effect of ATRA-induced leukemic cell differentiation on Brd7 gene expression in leukemia cell lines].

This study was purposed to investigate the relationship between brd7 gene and differentiation of leukemia cells and the role of brd7 gene in differentiation of leukemia cells. The HL-60 and K562 cell lines were induced by all-trans retinoic acid (ATRA) for 7 days, then the cell morphologic change was observed under inverted microscope with Wright-Giema staining, the expression level of CD11b was detected by flow cytometry for evaluating cell differentiation level, the expression changes of BRD7 protein before inducing differentiation and in process of cell differentiation were determined by Western blot. The results showed that ATRA could inhibit the proliferation and induce differentiation of HL-60 cells, but no differentiation in K562 cells was induced by ATRA.

[Expression and activity of glycosylphosphatidylinositol-specific phospholipase d mRNA in bone marrow mononuclear cells isolated from patient with acute myeloid leukemia and their significance].

This study was purposed to investigate the expression and significance of glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) in bone marrow mononuclear cells (BMMNC) isolated from patients with acute myeloid leukemia (AML), GPI-PLD activity in BMMNC isolated from 78 patients with AML and 15 normal persons was measured by using GPI-anchored placental alkaline phosphatase (PLAP) as a substrate and Triton X-114 phase partitioning. The GPI-PLD mRNA expression was measured by semi-quantitive reverse transcription-polymerase chain reaction (RT-PCR). The results showed that the mRNA expression level and activity of GPI-PLD in BMMNC from de novo AML patients were 1.

[Expression of DLK1 gene in acute leukemias and its function in erythroid differentiation of K562 cell line].

Objective: To determine the expression of DLK1 gene in acute leukemias (AL) and its function in erythroid differentiation of K562 cells.

Methods: We detected the expression of DLK1 gene in 65 different acute leukemia categories (a test group) and 34 normal bone marrow controls (a control group) with RT-PCR. DLK1 protein in 20 out of the 65 AL patients and 13 of the 34 controls was assayed by Western blot.

[Effect of GPI-PLD on adhesion function of bone marrow mononuclear cell from patients with myeloid leukemia and its mechanism].

To explore the effect of glycosyl-phosphatidyl inositol-specific phospholipase D (GPI-PLD) on the adhesion function of bone marrow mononuclear cell from patients with myeloid leukemia and analyze its mechanism, the activity of GPI-PLD in bone marrow mononuclear cell from the patients were measured by using GPI-anchored placental alkaline phosphatase (PLAP) as substrate and Triton-X114 partitioning; the adhesion rate and CD24 expression of these cells were measured by MTT and immunohistochemical method respectively, when these cells were or were not treated by 1 mmol/L 1,10-phenanthroline for 5 hours. The results showed that the GPI-PLD activity of bone marrow mononuclear cells from the patients was significantly inhibited after being treated by 1 mmol/L 1, 10-phenanthroline for 5 hours [(42.08 +/- 7.

[Effect of glycoprotein alpha II bA2334C mutation on the biosynthesis and transportation of alpha II bbeta3 complex].

Objective: To study the effect of glycoprotein (GP) alpha II bA2334C mutation on the biosynthesis and expression of alpha II bbeta3 complex.

Methods: The GP alpha II bA2334C eukaryotic expression plasmid pc3.1-2334M2b was constructed.

[GFP fused to the cytoplasmic tail of integrin alphaIIb allows the normal expression of alphaIIb beta3 compound in CHO cells].

To investigate the effect of GFP fused to C terminal of integrin alpha(IIb) on the biosynthesis and expression of alpha(IIb) beta(3) compound, the alpha(IIb) GFP expression plamid, named palpha(IIb) GFP, the cDNA of alpha(IIb) was constructed from p3.1-2b and fused to pEGFP-N1 in frame. When the sequence of palpha(IIb) GFP was confirmed by sequencing it was transferred to Chinese Hamster Ovary (CHO) cells with or without p3.

[p73 gene expression in apoptotic process of acute myeloid leukemia cell line U937 induced by methotrexate].

The purpose of this investigation was to study the variation of p73 gene expression in the apoptotic process of acute myeloid leukemia (AML) cell line U937 induced by methotrexate (MTX). Morphological changes of apoptotic cells were observed with microscopy and Wright's + Giemsa staining. DNA ladder and cell cycle were examined by agarose gel electrophoresis and flow cytometry respectively.