Change of cytokine expressions on bone marrow mesenchymal stem cells in patients with bone marrow failure syndromes and its significance / 中国实验血液学杂志

This study was aimed to investigate the expressions of multiple cytokines on bone marrow mesenchymal stem cells (MSC) in patients with aplastic anemia (AA) and myelodysplastic syndrome (MDS), and its significance. The semi-quantitative reverse transcriptase-PCR (RT-PCR) was used to detect the expressions of IL-1β, SCF, G-CSF at mRNA level in bone marrow MSC of patients with AA and MDS. The real time quantitative polymerase chain reaction (RQ-PCR) technique was used to detect the mRNA expression of TPO in bone marrow MSC of AA and MDS patients. The results indicated that the expression of SCF in AA group was much lower than that in the normal control group (p < 0.05), and the expression of TPO in AA group was higher than that in the normal control group (p < 0.05), while the expression of IL-1β of AA had no significant difference when compared with the normal control group (p > 0.05). Compared with normal control group, the expressions of SCF of MDS patients was lower (p < 0.05), but the expressions of IL-1β and TPO did not show significant difference (p > 0.05). The expressions of IL-1β, SCF and TPO were no significant difference between AA and MDS groups (p > 0.05). Neither the AA patients, MDS patients nor the normal control group had the expression of G-CSF. It is concluded that the expression of SCF and TPO in bone marrow MSC of AA patients are obviously abnormal, the expression of SCF is also abnormal in bone marrow MSC of MDS patients.

Effect of bortezomib and arabinoside on proliferation and apoptosis of K562 cell / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the effect of bortezomib (Bor) alone and in combination with arabinoside (Ara-C) on proliferation and apoptosis of leukemia cell line K562.</p><p><b>METHODS</b>K562 cells were treated with 20 nmol/L Bor and 0.2 microg/ml Ara-C alone and in combination for 48 h. MTT was used to study the inhibitory effects on cell growth and the apoptosis rate was analysed by flow cytometry. After K562 cells treated with 20 nmol/L Bor or 0.2 microg/ml Ara-C for 6 h, the activity of NF-kappaB was analyzed by SP immunohistochemistry and cell cycle by flow cytometry.</p><p><b>RESULTS</b>The inhibition and apoptosis rates of K562 cells in combination groups were higher than those in the two single treatment groups (P < 0.01), especially in the combined treatment group in which K562 cells were treated first with Ara-C for 6 h then with Bor combined,the inhibition and apoptosis rates were the highest [(81.5 +/- 4.0)% and (29.2 +/- 3.1)%, respectively] (P < 0.01). In the other two combined groups in which the cells were treated with Bor for 6 h then with Ara-C combined, or treated with the two drugs simultaneously, the inhibition and apoptosis rates were (54.1 +/- 4.2)% and (18.7 +/- 3.5)%, and (66.2 +/- 2.8)% and (21.1 +/- 2.2)%, respectively. Treatment of K562 cells with 20 nmol/L Bor for 6 h, the activity of NF-kappaB was decreased significantly, and the cells were apparently arrested in G(2)/M phase, and treatment with 0.2 microg/ml Ara-C in the same manner, the activity of NF-kappaB was increased significantly, and the cells were apparently arrested in G(1) phase.</p><p><b>CONCLUSIONS</b>Bor can effectively inhibit K562 cell proliferation, and induced its apoptosis. This effect was enhanced significantly when in combination with Ara-C. Pretreatment of K562 cells with Ara-C lead to the increased activity of NF-kappaB and the fraction of G(1) phase cells.</p>

Effects of human bone marrow mesenchymal stem cells on proliferation and apoptosis of K562 cells / 中国实验血液学杂志

This study was aimed to compare K562 cell proliferation, cell cycle and apoptosis before and after adhesive culture with MSCs of the same and different counts, so as to investigate the effect of human bone marrow mesenchymal stem cells (MSCs) on the growth of K562 cells. Culture system of bone marrow MSCs and co-culture system of K562 cells and BMSCs in vitro were established. And K562 cell proliferation curves were drawn by co-cultured of K562 cells with different counts of BMSCs. Cell cycle and apoptosis were determined by flow cytometry. The results showed that compared with the control, the proliferation of K562 cells cultured with the same amounts of MSCs was inhibited. After co-culture with the different amounts of MSCs, MSCs exhibited a dose-dependent anti-proliferation effect on K562 cells. The percentages of K562 cells in G(1) phase and G(2) phase were higher than those of the control. It is concluded that the normal bone marrow mesenchymal stem cells can inhibit the proliferation, the progress of cell cycle and the rate of apoptosis of K562 cells. As the number of mesenchymal stem cells increased, their anti-proliferation effect on the K562 cells were enhanced in a certain range.

Expression of vascular cell adhesion molecule-1 in patients with multiple myeloma and its significance / 中国实验血液学杂志

In order to investigate the expression of vascular cell adhesion molecule-1 (VCAM-1) in patients with multiple myeloma and its significance, the expression of VCAM-1 in 23 patients were detected by reverse transcription-PCR (RT-PCR) and then compared with that in normal control. The results showed that the expression of VCAM-1 in patients with newly diagnosed and relapsed/refractory multiple myeloma was much higher than that in normal control and in patients reached plateau stage (p < 0.05). There was no statistically significant difference between newly diagnosed and relapsed/refractory patients (p > 0.05). It is concluded that the expression of VCAM-1 in patients with multiple myeloma is abnormal, which may be an important factor for the pathogenesis of multiple myeloma.

Effects of proteasome inhibitor bortezomib on NF-kappaB activity and ICAM-1 mRNA expression of K562 cells / 中国实验血液学杂志

This study was aimed to investigate the effects of proteasome inhibitor bortezomib (Velcade, PS-341) on the activation of NF-kappaB and the expression of intercellular adhesion molecule-1 (ICAM-1) in K562 cells. The K562 cells were incubated in the culture of RPMI 1640 with 10% calf serum in 12-well plates and exposed to 0, 10, 20, 30, 50 and 100 nmol/L of bortezomib for 6 hours. The activation of NF-kappaB was analyzed by SP immunohistochemistry, meanwhile RT-PCR was performed to detect expression of ICAM-1. The results showed that the activation of NF-kappaB and the expression of ICAM-1 in K562 cells decreased significantly after bortezomib treatment. The inhibitory effect on ICAM-1 was probably related with the activity suppression of NF-kappaB. It is concluded that proteasome inhibitor bortezomib downregulates the expression of K562 cell ICAM-1 by inhibiting the activity of NF-kappaB, which provides a new way for the target therapy in acute leukemia.