Cucurbitacin B induces apoptosis and S phase cell cycle arrest in BEL-7402 human hepatocellular carcinoma cells and is effective via oral administration.

Cucurbitacin B is an anti-cancer drug candidate and its efficacy has been demonstrated in hepatocellular carcinoma (HCC). To explore its mechanism against HCC, BEL-7402 cells were treated with cucurbitacin B in vitro. Treatment with cucurbitacin B induced S phase arrest and apoptosis. The growth inhibition effect was associated with cyclin D1 and cdc-2 down regulations. Western blotting analysis of cell signaling molecules indicated that cucurbitacin B inhibited c-Raf activation without affecting STAT3 phosphorylation. Moreover, in vivo study demonstrated that cucurbitacin B is effective against BEL-7402 xenograft when administrated orally.

Coriolus versicolor (Yunzhi) extract attenuates growth of human leukemia xenografts and induces apoptosis through the mitochondrial pathway.

Coriolus versicolor (CV), also called Yunzhi, has been demonstrated to exert anti-tumor effects on various types of cancer cells. Our previous studies have demonstrated that a standardized aqueous ethanol extract prepared from CV inhibited the proliferation of human leukemia cells via induction of apoptosis. The present study aimed to evaluate the underlying mechanisms of apoptosis through modulation of Bax, Bcl-2 and cytochrome c protein expressions in a human pro-myelocytic leukemia (HL-60) cell line, as well as the potential of the CV extract as anti-leukemia agent using the athymic mouse xenograft model. Our results demonstrated that the CV extract dose-dependently suppressed the proliferation of HL-60 cells (IC50 = 150.6 microg/ml), with increased nucleosome production from apoptotic cells. Expression of pro-apoptotic protein Bax was significantly up-regulated in HL-60 cells treated with the CV extract, especially after 16 and 24 h. Meanwhile, expression of anti-apoptotic protein Bcl-2 was concomitantly down-regulated, as reflected by the increased Bax/Bcl-2 ratio. The CV extract markedly, but transiently, promoted the release of cytochrome c from mitochondria to cytosol after 24-h incubation. In vivo studies in the athymic nude mouse xenograft model also confirmed the growth-inhibitory activity of the CV extract on human leukemia cells. In conclusion, the CV extract attenuated the human leukemia cell proliferation in vivo, and in vitro possibly by inducing apoptosis through the mitochondrial pathway. The CV extract is likely to be valuable for the treatment of some forms of human leukemia.

Differential anti-tumor activity of coriolus versicolor (Yunzhi) extract through p53- and/or Bcl-2-dependent apoptotic pathway in human breast cancer cells.

Coriolus versicolor (CV), also called Yunzhi, has been demonstrated to exert anti-tumor effects on various types of cancer cells, but the underlying mechanism has not been fully elucidated. The present study aimed to evaluate the in vitro anti-tumor activity of a standardized aqueous ethanol extract prepared from CV on four breast cancer cell lines using MTT assay, and test whether the mechanism involves apoptosis induction and modulation of p53 and Bcl-2 protein expressions using cell death detection ELISA, p53 and Bcl-2 ELISAs respectively. Our results demonstrated that the CV extract dose-dependently suppressed the proliferation of three breast tumor cell lines, with ascending order of IC50 values: T-47D, MCF-7, MDA-MB-231, while BT-20 cells were not significantly affected. Tumoricidal activity of the CV extract was found to be comparable to a chemotherapeutic anti-cancer drug, mitomycin C. Nucleosome productions in apoptotic MDA-MB-231, MCF-7 and T-47D cells were significantly augmented in a time-dependent manner and paralleled the anti-proliferative activity of CV extract. Expression of p53 protein was significantly upregulated only in T-47D cells treated with the CV extract in a dose- and time-dependent fashion, but not in MCF-7 (except at 400 mug/ml after 16 h) and MDA-MB-231 cells. The CV extract significantly induced a dose-dependent downregulation of Bcl-2 protein expression in MCF-7 and T-47D cells, but not in MDA-MB-231 cells. These results suggested that apoptosis induction, differentially dependent of p53 and Bcl-2 expressions, might be the possible mechanism of CV extract-mediated cytotoxicity in human breast cancer cells in vitro.

Expression of cyclin B1 and cyclin dependent kinase inhibitor p21 in lymphocytes in patients with systemic lupus erythematosus.

OBJECTIVE: The roles of cyclins and cyclin dependent kinase (CDK) inhibitors of lymphocytes in the pathogenesis of systemic lupus erythematosus (SLE) are unclear. We measured the expression of cyclin B1 and CDK inhibitor p21 in peripheral blood lymphocytes (PBL) from patients with SLE and controls. METHODS: PBL from 40 SLE patients with renal disease (RSLE), 40 SLE patients without renal disease (SLE), and 28 healthy control subjects were cultured with phytohemagglutinin (PHA). Bivariate distribution of cyclin B1 or p21 expression versus cellular DNA content was assessed by flow cytometry. RESULTS: Expression of p21 in lymphocytes was significantly lower in patients with RSLE and with SLE than controls (RSLE vs controls and SLE vs controls, both p < 0.001). Expression of cyclin B1 was similar in all groups. The percentages of RSLE lymphocytes in G0/G1 and S phase were significantly reduced and elevated, respectively, compared with controls. CONCLUSION: Downregulated p21 in PHA stimulated PBL from patients with SLE may be closely related to aberration of cell division in SLE lymphocytes.

Apoptosis and B-cell lymphoma-2 of peripheral blood T lymphocytes and soluble fas in patients with allergic asthma.

STUDY OBJECTIVE: s: The dysregulation of apoptosis and the expression of apoptosis-related molecules of allergen-reactive T lymphocytes have been suggested to play a key role in the development and maintenance of the inflammatory reactions in allergic asthma. Glucocorticoids are effective drugs for treating allergic inflammation. In this study, we investigated the effect of dexamethasone (DEX) on the apoptosis and B-cell lymphoma (Bcl)-2 expression of peripheral blood T lymphocytes as well as the soluble form of Fas (sFas) in allergic asthmatic patients. METHODS: Peripheral blood lymphocytes from 41 allergic asthmatic patients and 30 age-matched and sex-matched control subjects were treated with 0.1 and 1 micro M DEX. The percentages of apoptosis and expression of the Bcl-2 molecule in T lymphocytes were assessed by flow cytometry. The plasma concentration of sFas was measured using the enzyme-linked immunosorbent assay. RESULTS: DEX (0.1 and 1 micro M) could induce the apoptosis of T lymphocytes from allergic asthmatic patients and control subjects in a dose-dependent manner in vitro. The apoptotic susceptibility of T lymphocytes to DEX and the plasma sFas concentration were significantly higher in allergic asthmatics. The ex vivo expression of Bcl-2 was significantly lower in the T lymphocytes of asthmatic patients than in those of the control subjects. However, DEX did not have any significant effect on the expression of Bcl-2 in vitro. CONCLUSIONS: The T lymphocytes of asthmatic patients have higher apoptotic susceptibility to DEX treatment in vitro and a lower expression of the Bcl-2 molecule.

Predominant hematopoietic origin of cell-free DNA in plasma and serum after sex-mismatched bone marrow transplantation.

BACKGROUND: Despite current interest in the biology and diagnostic applications of cell-free DNA in plasma and serum, the cellular origin of this DNA is poorly understood. We used a sex-mismatched bone marrow transplantation model to study the relative contribution of hematopoietic and nonhematopoietic cells to circulating DNA. METHODS: We studied 22 sex-mismatched bone marrow transplantation patients. Paired buffy coat and plasma samples were obtained from all 22 patients. Matching serum samples were also obtained from seven of them. Plasma DNA, serum DNA, and buffy coat were quantified by real-time PCR of the SRY and beta-globin gene DNA. To investigate the effects of blood drawing and other preanalytical variables on plasma DNA concentrations, blood samples were also collected from 14 individuals who had not received transplants. The effects of blood sampling by syringe and needle, centrifugation, and time delay in blood processing were studied. RESULTS: The median percentage of Y-chromosome DNA in the plasma in female patients receiving bone marrow from male donors (59.5%) differed significantly (P <0.001) from that in the male patients receiving bone marrow from female donors (6.9%). This indicated that plasma DNA in the bone marrow transplantation recipients was predominantly of donor origin. Compared with paired plasma samples, serum samples had a median 14-fold higher DNA concentration, with the additional DNA being of donor origin. Control experiments indicated that none of the three tested preanalytical variables contributed to a significant change in cell-free DNA concentration. CONCLUSIONS: After bone marrow transplantation, the DNA in plasma and serum is predominantly hematopoietic in origin. Apart from the biological implications of this observation, this finding suggests that plasma and serum can be used as alternative materials for the study of postbone marrow transplantation chimerism.