Small molecule BH3 mimetics comprise a promising new chemotherapeutic strategy for treating relapsed or chemoresistant cancer. In this study, we investigated the cellular mechanism of action by which BM-1197, a Bcl-xL/Bcl-2 dual inhibitor, triggers apoptosis in a panel of colorectal cancer (CRC) lines. Using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, we determined that BM-1197 inhibited CRC cell growth in a concentration- and time-dependent manner. The 50 % inhibitory concentration (IC50) values for the most sensitive cell lines, SW620 and SW480, ranged from 0.07 to 1.10 μM in response to a 72-h treatment. In CRC cells, BM-1197 induced apoptotic death without affecting the expression of Bcl-2 family proteins. However, BM-1197 effectively triggered a conformational change in Bax, releasing Bim from Bcl-xL by disrupting the interaction between Bcl-xL and Bak/Bax. Compared with the control group, BM-1197 treatment significantly increased the fraction of SW480 cells in the sub-G1 phase, the apoptosis rate, and cellular internucleosomal DNA fragmentation. The proapoptotic activity was associated with cytochrome c release, caspase-3 activation, and PARP-1 cleavage. Collectively, BM-1197 effectively suppressed the growth of the human CRC cell line SW480 by inducing mitochondria-dependent apoptotic cell death. These data have specific implications for the in vivo analysis and clinical evaluation of BM-1197 in CRC.

Colorectal cancer (CRC) is a worldwide malignancy of high incidence and mortality. At present, there is a lack of effective drugs against CRC. The B‑cell leukemia/lymphoma 2 (Bcl‑2) protein family members are considered to be closely associated with tumorigenesis and the chemoresistance of CRC. As a novel gossypol derivative targeting antiapoptotic proteins of the Bcl‑2 family, apogossypolone (ApoG2) exhibits antitumor properties in various cancer types, although its effects against CRC remain to be fully elucidated. In the present study, the cytotoxicity of ApoG2 in vitro on CRC cells was investigated, with the aim of elucidating the underlying mechanism. Using an MTT assay, ApoG2 was revealed to inhibit the growth of the HT29, SW480 and HCT116 CRC cell lines in a dose‑ and a time‑dependent manner. Hoechst staining revealed that ApoG2 induced CRC cell apoptosis, marked by morphological changes, including cell shrinkage and nuclear fragmentation. Flow cytometric analysis also detected a higher apoptotic ratio following treatment with ApoG2. The ratio was dependent upon the concentration of ApoG2, which the cells were exposed to, and the duration of the exposure. Western blot analysis and immunoprecipitation experiments revealed that ApoG2 treatment led to the downregulation of the protein expression of Mcl‑1, and the interruption of the binding of Mcl‑1 to the protein Bax. Furthermore, treatment with ApoG2 led to the release of cytochrome c into the cytoplasm and the activation of caspases 3 and 7. The present study revealed that ApoG2 inhibited the proliferation of the CRC cell lines through mitochondrial signaling pathway‑dependent apoptosis, which may be associated with the disruption of the function of the Mcl‑1 protein by ApoG2.

Objective To compare high performance liquid chromatography (HPLC) and enzyme multiplied irmunoassay technique (EMIT) method in monitoring mycophenolic acid (MPA) in renal transplantation patients.Method Plasma samples were collected from 31 adult kidney transplant recipients at 0.5,1.5,4 and 9 h after administration of mycophenolate mofetil (MMF).All these patients were given MMF,tacrolimus and prednisolone for immunosuppression.Both EMIT and HPLC were employed to determine plasma MPA concentration.Method comparison was performed using Bland & Altman and Passing & Bablok analysis.Result HPLC method and EMIT method exhibited a liner range of 0.1-50.0 mg/L and 0.1-15.0 mg/L.All of MPA concentrations at each time point had no normal distribution.The MPA concentration determined by EMIT was higher than HPLC by 1.44 (-1.88-13.58 rg/L,P＜0.05).The EMIT assay showed a mean positive bias of 29.0％ in concentration,and 19.4％ in AUC0-12h by Bland & Altman plots.The Passing & Bablok regression analysis gave an equation of MPAEMTT =0.3926 + 1.1121 × MPAHPLC,and AUCEMIT =4.7911 + 1.0929 × AUCHPLC.Conclusion It should be considered that the putative therapeutic range for MPA with the EMIT assay is higher than the range using HPLC.

Objective To investigate the apoptosis-inducing effect of ApoG2 on gastric carcinoma cells and its influence on Wnt6 expression. Methods Experiments were performed on human gastric carcino-ma cell line BGC823. Cell viability,cell morphology and cell cycle were detected after ApoG2 treatment. The mRNA Levels of Bcl2,Bax,Bak and Wnt6 protein were also examined. Results BGC823 cell growth was significantly inhibited by ApoG2 in a dose-dependent manner. Apoptotic cells were observed by fluorescence microscope using Hoechst staining after ApoG2 treatment. Cell cycle analysis of ApoG2 treated cells by flow cy-tometry displayed increased percentage of sub-G1 peak. Increased mRNA levels of Bax and Bak after ApoG2 treatment were observed,while both Bcl2 mRNA level and Wnt6 protein level were decreased. Conclusions ApoG2 can significantly inhibit the growth of human gastric carcinoma BGC823 cells and induce cell apoptosis.This effect is probably mediated by the suppression of Wnt6 protein which downregulates Bcl2 gene expression and upregulates Bax and Bak gene expression.