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A new 1,4,7-triazacyclononane derivative, 4-benzyloxy-benzyl-1,4,7-triazacyclononane (btacn), and three associated cyclen complexes, Cu(btacn)Cl 2 , Zn(btacn)Cl 2 and [Cu(btacn) 2 ]·(ClO 4 ) 2 , were prepared to serve as DNA synthesis interferents. The compounds were characterized using IR, 1 H and 13 C NMR, ESI-MS, elemental analysis and X-ray single crystal diffraction methods, and their DNA damage mechanisms and cytotoxicities towards cancer and normal cells were studied. Among them, Cu(btacn)Cl 2 and [Cu(btacn) 2 ]·(ClO 4 ) 2 exhibit potent anti-proliferation activity in HepG-2 and HeLa cells, but low cytotoxicity in the normal cell models LO2 and HUVEC, giving SI values (IC 50 ratios) ranging from 2.45 to 7.09-times higher than that of cisplatin. DNA binding and cleavage studies suggested that [Cu(btacn) 2 ]·(ClO 4 ) 2 can more easily intercalate into CT-DNA than Cu(btacn)Cl 2 , which is consistent with the results of G2/S phase arrest and apoptosis in HepG-2 cells involving the complexes. In contrast, Zn(btacn)Cl 2 demonstrated weak DNA binding and no obvious cytotoxicity. The results suggest that Cu(btacn)Cl 2 and [Cu(btacn) 2 ]·(ClO 4 ) 2 mainly undergo redox processes to produce reactive oxygen species (ROS) that induce DNA degradation and mitochondrial damage.

Kinetochore‑associated proteins are critical components of mitotic checkpoints, which are essential for faithful chromosomal segregation and spindle assembly during cell division. Recent advances have demonstrated that kinetochore‑associated proteins are upregulated and serve significant roles in the carcinogenesis of numerous types of cancer. However, the effects of kinetochore‑associated protein 1 (KNTC1) on human cancer, particularly on esophageal squamous cell carcinoma (ESCC), remain unclear. The present study revealed that KNTC1 was highly expressed in ESCC cell lines. Subsequently, lentivirus‑mediated short hairpin RNAs were used to knockdown KNTC1 expression in human ESCC cell lines. Cell growth and viability were measured using multiparametric high‑content screening and the MTT assay, respectively. Cell apoptosis was assessed by staining cells with Annexin V‑allophycocyanin and was detected using FACScan flow cytometry. The results demonstrated that knockdown of KNTC1 effectively inhibited cell viability and increased apoptosis. In addition, a gene set enrichment analysis of online ESCC datasets indicated that KNTC1 overexpression was associated with increases in the mitotic spindle and hypoxia pathways, and decreases in the DNA repair and mismatch repair pathways. The findings of the present study suggested that KNTC1 may have an essential role in mediating cell viability and apoptosis in human ESCC cells and may serve as a novel therapeutic target for ESCC.

This study was aimed to investigate the effect of MK886, a mPGES-1 inhibitor, on apoptosis and drug resistance of leukemia HL-60/A cell line. Expression of mPGES-1 was assayed by QT-PCR and Western blot. The effect of MK886 on HL-60/A cell proliferation was assayed by CCK-8 method, and flow cytometry was used to detect cell apoptosis. The expression of Akt and P-Akt was detected by Western blot. PGE2 was measured by ELISA. Effect of MK886 (10 µmol/L) on the chemotherapeutic sensitivity of HL-60/A cells and expression of mdr-1 mRNA and P170 protein were investigated too. The results indicated the expression of mPGES-1 was higher in HL-60/A cells. MK886 inhibited HL-60/A cell proliferation and induced apoptosis in a time- and concentration-dependent manner. Expression of mPGES-1 and P-Akt and synthesis of PGE2 decreased significantly. MK886 reduced expression of mdr-1 and P170 protein and enhanced the sensitivity of HL-60/A cells to chemotherapeutic drugs. It is concluded that MK886 can inhibit HL-60/A cell proliferation, induce apoptosis and enhance sensitivity to chemotherapeutic drugs, the mechanism of which possibly associates to down-regulation of mPGES-1/PGE2 synthesis, reduction P-Akt expression and decreasing mdr-1 and P170 protein expression.

This study was aimed to clarify whether valproic acid (VPA) induces apoptosis of leukemia HL-60 cell line and its possible mechanism. The effect of different concentrations and treatment time of VPA on HL-60 cell proliferation was assayed by cytotoxicity test (CCK-8 method) and fluorescence microscopy, and flow cytometry was used to detect cell apoptosis. The expressions of telomerase subunit h-tert mRNA and apoptosis-related protein as well as caspase-3 activity were detected by real time-quantitative PCR, Western blot and ELISA respectively. The results indicated that VPA inhibited proliferation of HL-60 cells and induced cell apoptosis in a dose dependent manner (r = -0.87). The expressions of anti-apoptotic protein BCL-2 and h-tert mRNA were significantly decreased while the pro-apoptotic protein BAX and caspase-3 activity increased after treatment with VPA. The apoptosis rate of HL-60 cell was negatively correlated with expression of h-tert mRNA. It is concluded that VPA can inhibit leukemia HL-60 cell proliferation and induce apoptosis. The VPA displays anti-leukemia activity possibly through reducing h-tert mRNA and BCL-2 protein expression, increasing BAX expression and activity of caspase-3.

Cyclooxygenase-2 (COX-2) has been shown to be upregulated in a variety of tumors so that COX-2 may be a potential target in the treatment of cancer. In order to further explore the mechanism, we used RNA interference to study effects of the inhibition of COX-2 on esophageal squamous cell carcinoma (ESCC) lines. Western blot analysis demonstrated that COX-2 expression was significantly reduced in ESCC cells treated with the COX-2-specific siRNA. Furthermore, the COX-2 siRNA treatment inhibited cell proliferation and induced apoptosis in ESCC cells. In addition, the combination treatment of COX-2 siRNA and acidum acetil salicylicum (aspirin) has a synergistic effect. Therefore, this combination has potential as an anticancer therapy for the treatment of ESCC.

Bee pollen of Brassica campestris L. is widely used in China as a natural food supplement and an herbal medicine in strengthening the body's resistance against diseases including cancer. The present study was carried out to investigate the effect of a steroid fraction of chloroform extract from bee pollen of Brassica campestris L. on human cancer cell viability. Our studies show that among nine cancer cell lines of different origin (PC-3, LNCaP, MCF-7, Hela, BEL-7402, BCG-823, KB, A549 and HO8910), this steroid fraction displayed the strongest cytotoxicity in human prostate cancer PC-3 cells. The mode of cell death appeared to be apoptosis in PC-3 cells, as shown by flow-cytometric analysis and fluorescence microscopes. Caspase-3 activity was obviously enhanced after the cells were treated with the fraction. A time-dependent decrease in the expression of anti-apoptotic protein Bcl-2 was also observed by Western blot analysis. It is suggested that the steroid fraction could induce cytotoxicity in prostate cancer PC-3 cells by triggering apoptosis. The studies indicate that the steroid fraction of chloroform extract from bee pollen of Brassica campestris L. may be a promising candidate for the treatment of advanced prostate cancer., (Copyright (c) 2007 John Wiley & Sons, Ltd.)

Brassinolide is a plant sterol first isolated from pollen of rape (Brassica napus L.). The present study was carried out to investigate the effect of brassinolide on androgen-independent human prostate cancer PC-3 cell viability. Results showed that brassinolide could induce a time and concentration-dependent cytotoxicity in PC-3 cells. The mode of cell death appeared to be predominately apoptosis, as shown by flow-cytometric analysis, fluorescence and transmission electron microscopes. Caspase-3 activity was obviously increased after brassinolide treatment. Western blot studies indicated that treatment with brassinolide triggered a time-dependent decrease in the expression of anti-apoptotic protein Bcl-2. We suggest that brassinolide could induce cytotoxicity in PC-3 cells by triggering apoptosis. Brassinolide might therefore be a promising candidate for the treatment of prostate cancer.

Objective: To evaluate the effect of combined use of oncolytic virus and the chemotherapeutic agents mitomycin (MMC) in growth inhibition of human bladder cancer cell line T-24 in vitro., Methods: Human bladder cancer cell line T-24 was infected with oncolytic virus (ONYX-015) of different multiplicity of infection, or treated with MMC in addition to ONYX-015. The changes in the cell growth, morphology, and apoptosis of cultured T-24 cells were observed by means of cell counting and fluorescence microscopy after the treatments. The effects of the treatment protocols were also tested in nude mouse model of implanted subcutaneous tumor., Results: Combined use of ONYX-015 and MMC produced substantially stronger cytotoxic effect against T-24 cells than exclusive use of ONYX-015. In in vivo experiments, combination of oncolytic virus and MMC resulted in much more significant tumor growth inhibition than either of the agents used alone. Obvious T-24 cell apoptosis could be observed in response to combined ONYX-105 and MMC treatment and exclusive ONYX-105 treatment., Conclusions: ONYX-015 combined with MMC can produce significant cytotoxicity against T-24 cells and enhance therapeutic efficacy against bladder carcinoma.

Objective: To explore the possible mechanism of apoptosis induced by photodynamic therapy (PDT) in human pancreatic cancer cells Capan-1 with 2-butylamino-2-demethoxy-hypocrellin B (BAHB) as photosensitizer., Methods: The localization of BAHB in Capan-1 cells was studied, apoptosis was determined by DNA gel electrophoresis after PDT. The mitochondria membrane potential (DYm) and cytochrome C release were observed by laser scan confocal microscopy and Western blotting., Results: The low concentration photosensitizer was mainly localized in mitochondria and also in lysosomes when the concentration is high. DNA ladder analysis showed characteristic of apoptosis. The mitochondria membrane potential (DYm) showed a loss of 30% around, after 6 hours by PDT under laser scan confocal microscopy, which is caused by a sudden increase in the permeability of mitochondria membrane accompanied with apoptosis. In Western blotting, cytochrome C release was observed from the mitochondria into the cytoplasm during BAHB-induced apoptosis., Conclusion: The research suggests that BAHB-induced apoptosis is related to photosensitization of mitochondria.

Objective: The purpose of this study is to investigate the effect of superoxide anion on the apoptosis of cultured fibroblasts and the protective role of selenium and Vitamin E., Methods: Cultured fibroblasts (NIH3T3), with or without selenium or vitamin E in the medium, were treated by superoxide anion produced by xanthine/xanthine oxidase reaction system and changes in cell structure and DNA were observed microscopically and electrophoretically., Results: Apoptosis was observed when superoxide anion at a concentration of 5 nmol/L or 10 nmol/L had acted on the fibroblasts for 5-10 h. Selenium and Vitamin E in the medium inhibited the apoptosis significantly when their concentrations reached 1.15 mol/L and 2.3 mol/L respectively., Conclusion: Selenium and vitamin E have protective effect against the apoptosis induced by superoxide anion. The effect of selenium is more remarkable than that of vitamin E.

Aim: To explore the effects of glutamine on growth and apoptosis of hepatoma cells., Methods: Mice inoculated with hepatoma cell (H22) suspension subcutaneously at right axilla were orally administered with glutamine (GLN) solution. Human hepatoma cell culture (SMMC-7721) was treated with different concentrations of GLN solution. The content of malondialdehyde (MDA) and nitric oxide (NO) was detected in mice plasma and cell culture, and that of glutathione (GSH) was decected in cells. The inoculated tumor's growth in the mice and hepatoma cells' proliferation and apoptosis were observed., Results: When mice were administered orally with GLN solution (300 mg/kg), the growth of inoculated hepatoma was suppressed in the mice. When different concentrations of GLN solution were added in human hepatoma cell culture, the hepatoma cells' proliferation was inhibited and cells were induced to apoptosis, which was dependent on GLN concentration; meanwhile the contents of NO rose both in mice plasma and in cell culture, however MDA contents were slightly lowered in both, and the activity of GSH increased in the cells which had been ultrasonically shattered., Conclusion: Hepatoma cell apoptosis and tumor growth inhibition by GLN may be associated with its antioxidative activity and its intervention in hepatoma cell proliferation, and simultaneous release of NO.