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Objective: To study the effect of apoptotic drug Navitoclax (NTX) combined with chemotherapy drug Daunorubicin (DNR) on apoptosis of erythroleukemia cells., Methods: K562, HEL and TF-1 cells in logarithmic growth phase were treated with NTX, DNR and combination of the two drugs. CCK-8 test, Annexin V-DAPI double-staining flow cytometry, real-time RT-PCR were used to detect cell growth, cell apoptosis and expression of BAX, BAK, BCL-2, BCL-xl and BIM respectively. The effects of NTX, DNR and combination of the two drugs on apoptosis of K562, HEL and TF-1 cells were compared and analyzed., Results: NTX combined with DNR could significantly inhibit the growth of K562, HEL and TF-1 cells; Apoptosis detection results showed that the apoptotic rate of K562, HEL and TF-1 cells in combination group was significantly higher than that in NTX and DNR single group; the expression level of apoptosis-related genes BAK and BAX in K562 cells in combination group was significantly higher than that in two single drug groups, and the expression level of anti-apoptotic protein genes BCL-2 and BCL-xl was significantly lower than that in two single drug groups (P＜0.05); the expression level of BAK in HEL cells treated with combined drugs for 24 hours was higher than that in DNR group (P ＜ 0.05); the expression level of BCL-2 in TF-1 cells treated with combined drugs for 24 hours was lower than that in two single drugs groups while the expression level of BAK in 48 hours was the highest in combined drugs group, and the expression level of BCL-2 and BCL-xl in combined drugs group was lower than that in NTX group (P＜0.05)., Conclusion: NTX combined with DNR can significantly promote the apoptosis of erythroleukemia cell lines K562, HEL and TF-1, and induce the expression of apoptosis-related genes. This study provides a new scheme for the clinical treatment of erythroleukemia.

Aim: Carvacrol (2-methyl-5-isopropylphenol), a phenolic monoterpene in the essential oils of the genera Origanum and Thymus, has been shown to exert a variety of therapeutic effects. Here we examined whether carvacrol protected neuroblastoma SH-SY5Y cells against Fe(2+)-induced apoptosis and explored the underlying mechanisms., Methods: Neuroblastoma SH-SY5Y cells were incubated with Fe(2+) for 24 h, and the cell viability was assessed with CCK-8 assay. TUNEL assay and flow cytometric analysis were performed to evaluate cell apoptosis. The mRNA levels of pro-inflammatory cytokines and NF-κB p65 were determined using qPCR. The expression of relevant proteins was determined using Western blot analysis or immunofluorescence staining., Results: Treatment of SH-SY5Y cells with Fe(2+) (50-200 μmol/L) dose-dependently decreased the cell viability, which was significantly attenuated by pretreatment with carvacrol (164 and 333 μmol/L). Treatment with Fe(2+) increased the Bax level and caspase-3 activity, and decreased the Bcl-2 level, resulting in cell apoptosis. Furthermore, treatment with Fe(2+) significantly increased the gene expression of IL-1β, IL-6 and TNF-α, and induced the nuclear translocation of NF-κB. Treatment with Fe(2+) also significantly increased the phosphorylation of p38, ERK, JNK and IKK in the cells. Pretreatment with carvacrol significantly inhibited Fe(2+)-induced activation of NF-κB, expression of the pro-inflammatory cytokines, and cell apoptosis. Moreover, pretreatment with carvacrol inhibited Fe(2+)-induced phosphorylation of JNK and IKK, but not p38 and ERK in the cells., Conclusion: Carvacrol protects neuroblastoma SH-SY5Y cells against Fe(2+)-induced apoptosis, which may result from suppressing the MAPK/JNK-NF-κB signaling pathways.

Water temperature is an important environmental factor in aquaculture farming that affects the survival and growth of organisms. The change in culture water temperature may not only modify various chemical and biological processes but also affect the status of fish populations. In previous studies, high temperature induced apoptosis and oxidative stress. However, the precise mechanism and the pathways that are activated in fish are still unclear. In the present study, we investigated the effects of high temperature (34°C) on the induction of apoptosis and oxidative stress in pufferfish (Takifugu obscurus) blood cells. The data showed that high temperature exposure increased oxygen species (ROS), cytoplasmic free-Ca(2+) concentration and cell apoptosis. To test the apoptotic pathway, the expression pattern of some key apoptotic related genes including P53, Bax, caspase 9 and caspase 3 were examined. The results showed that acute high temperature stress induced up-regulation of these genes, suggesting that the p53-Bax pathway and the caspase-dependent apoptotic pathway could be involved in apoptosis induced by high temperature stress. Furthermore, the gene expression of antioxidant enzymes (Cu/Zn-SOD, Mn-SOD, CAT, GPx, and GR) and heat shock proteins (HSP90 and HSP70) in the blood cells were induced by high temperature stress. Taken together, our results showed that high temperature-induced oxidative stress may cause pufferfish blood cells apoptosis, and cooperatively activated p53-Bax and caspase-dependent apoptotic pathway., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Conventional adjuvant chemotherapies for bladder transitional cell carcinomas (TCCs) may cause strong systemic toxicity and local irritation. Non-toxic resveratrol inhibits TCC cell growth but its feasibility in clinical management of TCCs remains obscure. This study aimed to evaluate the safety and anti-TCC efficacy of resveratrol, using the experimental models closer to the clinical treatment condition. Human TCC EJ cells were exposed to 100 µM, 150 µM and 200 µM resveratrol respectively for 1 hour and 2 hours to mimic intravesical drug instillation and the cell responses were analyzed by multiple experimental approaches. An orthotopic TCC nude mouse model was established by injecting EJ cells into the sub-urothelial layer and used for short-term intravesical resveratrol instillation. The safety of resveratrol instillation was evaluated and compared with that of MCC. The results revealed that 2 h 150 µM or 200 µM resveratrol treatment leaded to remarkable S phase arrest and apoptosis at 72 h time-point, accompanied with attenuated phosphorylation, nuclear translocation and transcription of STAT3, down-regulation of STAT3 downstream genes (survivin, cyclinD1, c-Myc and VEGF) and nuclear translocations of Sirt1 and p53. The importance of STAT3 signaling in cell growth was confirmed by treating EJ cells with JAK2 inhibitor tyrphostin AG490. The efficacy and safety of resveratrol instillation were proved by the findings from nude mouse orthotopic xenograft models, because this treatment caused growth suppression, distinctive apoptosis and STAT3 inactivation of the transplanted tumors without affecting normal urothelium. Our results thus suggest for the first time the practical values of resveratrol as a safe and effective agent in the post-operative treatment of TCCs.

Purpose: To further elucidate the correlation of resveratrol sensitivities with biotransformation activities of human and rat glioblastoma cells for personalized anti-glioblastoma therapy., Methods: Resveratrol sensitivity of human U251 and rat RG2 and C6 glioblastoma cells was evaluated by 3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide/MTT, flow cytometry, and TUNEL assays. The metabolic patterns of those cell lines were analyzed by high-performance liquid chromatography/HPLC coupled with tandem mass spectrum/MS/MS, and high-resolution mass spectrometry/HRMS. Immunocytochemical staining and Western blotting were employed to check resveratrol metabolic enzyme expression., Results: Both rat RG2 and C6 and human U251 glioblastoma cells are sensitive to 100 μM resveratrol in terms of growth arrest and increased apoptotic fraction. The main resveratrol metabolite in U251 cells is monosulfate biotransformed by sulfotransferases/SULTs and in RG2 and C6 cells is monoglucuronide generated by UDP-glucuronosyltransferase/UGT. Both metabolites show lesser therapeutic efficacy. Although brain-associated UGTs (UGT1A6, 2B7, and 8) and SULTs (SULT1A1, 1C2, and 4A1) are expressed in rat and human glioma cells, the overall level of UGTs is predominant in the rat and SULTs in human glioblastoma cells. In similar to SULT expression pattern, UGT1A6, 2B7, and 8 are frequently downregulated (84.6 %, 82/97; 90.7 %, 88/97; 80.4 %, 78/97) in human glioblastoma tissues., Conclusion: Our results suggest (1) the decreased resveratrol biotransforming activity in rat and human resveratrol-sensitive glioblastoma cells; (2) the discrepant resveratrol metabolic patterns between human and rat glioblastoma cells; (3) the more powerful anti-glioblastoma efficacy of trans-resveratrol rather than resveratrol monoglucuronide or monosulfate; and (4) the value of RG2 and C6 cells in establishing resveratrol-based rat in vivo therapeutic model.

Crocin is a pharmacologically active component of Crocus sativus L. (saffron) and has been reported to be useful in the treatment of neuronal damage. In the present study, we investigated the neuroprotective effect of crocin on retinal ganglion cells (RGCs) after retinal ischaemia/reperfusion (IR) injury, and our results show that crocin acts through the PI3K/AKT signalling pathway. Retinal IR injury was induced by raising the intraocular pressure of Sprague-Dawley rats to 110 mmHg for 60 min. The neuroprotective effect of crocin was determined by quantifying the surviving RGCs and apoptotic RGCs following IR injury by means of retrograde labelling and TUNEL staining, respectively. The phosphorylated AKT protein level was determined by western blot and immunohistochemical analysis. To determine the extent to which the PI3K/AKT pathway contributes to the neuroprotective effect of crocin, experiments were also performed using the PI3K inhibitor LY294002. Compared with the IR + vehicle group, crocin (50 mg/kg) treatment enhanced RGC survival by approximately 36% and decreased RGC apoptosis by 44% after retinal IR injury. Western blot and immunohistochemical analysis demonstrated that the PI3K/AKT pathway was activated by crocin in the ganglion cell layer after retinal IR injury. Intravitreal injection of LY294002 blocked the neuroprotective effect of crocin on IR-induced RGC death. In conclusion, crocin prevents retinal IR-induced apoptosis of RGCs by activating the PI3K/AKT signalling pathway., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

We hypothesize that adrenal insufficiency in acute necrotizing pancreatitis (ANP) is attributable to hemorrhagic inflammation, necrosis, and apoptosis of the adrenal cortex. Arguments to support this view are presented in the study that investigated morphological and functional changes of adrenal and the distinct roles of inflammatory mediator secretory phospholipase A(2) (sPLA(2)) and apoptosis-related genes Bax and Bcl-2 played in acute adrenal injury in ANP. After ANP model was induced, pancreatic histology, serum amylase, sPLA(2), and corticosterone were analyzed. The adrenal morphology, apoptotic cells by TUNEL assay, and ultrastructures were observed. sPLA(2)-IIA and Bcl-2 and Bax expressions were detected by immunohistochemistry. Histopathologic grading of adrenal was higher in ANP group than in controls. Serum corticosterone was stimulated to maximal level at 3 h, then dropped to the bottom at 24 h (P<0.05). Apoptotic index, sPLA2-IIA, and Bax expression were increased steeply after pancreatitis, and the Bax/Bcl-2 ratio was elevated gradually (P<0.05). Sustained decrease in serum corticosterone level following adrenal injury during ANP appears to be, in part, due to the crucial roles of inflammation and apoptosis in adrenal cortex. These findings could suggest that sPLA2, Bax, and Bcl-2 may be involved in the course of adrenal injury after ANP.

Resveratrol promotes differentiation and apoptosis of medulloblastoma cells by suppressing STAT3 signaling and a range of cancer-associated gene expression. However, Bcl-2, a common target of STAT3 and NF-κB signaling, is distinctly up-regulated in resveratrol-treated medulloblastoma cells, indicating potential effects of NF-κB in Bcl-2 expression and anti-medulloblastoma efficiency of resveratrol. To clarify this point, the status of NF-κB signaling and the consequence of NF-κB inhibition in UW228-2 and UW228-3 medulloblastoma cells without and with resveratrol treatment were evaluated by several experimental approaches. The results revealed that resveratrol activated NF-κB signaling in both cell lines at the 4-h treatment point, and the treated cells sequentially exhibited Bcl-2 up-regulation, neuronal-like phenotype with synaptophisin expression, and, eventually, apoptosis. Pyrrolidine dithiocarbamate (PDTC) treatment inhibited NF-κB activation and Bcl-2 expression and committed resveratrol-treated cells to apoptosis at the 8-h time point without the step of neuron-oriented differentiation. On the other hand, a single 50 μg/ml lipopolysaccharide (LPS) treatment activated NF-κB signaling accompanied with sustained proliferation and neuron-like differentiation. Tissue microarray-based immunohistochemical staining showed significantly different (P < 0.001) p65 nuclear translocation between the neurons of tumor-surrounding cerebella (10/10; 100%) and medulloblastoma tissues (20/117; 17.09%). Additionally, synaptophysin production was found in 83.64% of p65-positive and in 40.35% of p65-negative medulloblastoma cases. Our in-vitro and in-vivo results thus demonstrate the dual effects of NF-κB signaling on medulloblastoma cells by delaying resveratrol-induced apoptosis by up-regulating Bcl-2 expression or by involvement in neuronal-like differentiation in the absence of resveratrol. Therefore, appropriate inhibition of NF-κB activation may enhance the anti-medulloblastoma efficacy of resveratrol.

Cisplatin is a highly effective chemotherapeutic agent, but it has significant ototoxic side effects. Apoptosis is an important mechanism of cochlear hair cell loss following exposure to cisplatin. The present study examined the effects of phloretin, a natural polyphenolic compound found in apples and pears, on cisplatin-induced apoptosis. We found that phloretin induced the expression of heme oxygenase-1 (HO-1) protein in a concentration- and time-dependent manner. Phloretin induced nuclear factor-E2-related factor 2 (Nrf2) nuclear translocation, and dominant-negative Nrf2 attenuated phloretin-induced expression of HO-1. Phloretin activated the JNK, ERK and p38 mitogen-activated protein kinase (MAPK) pathways, and the JNK pathway played an important role in phloretin-induced HO-1 expression. Phloretin protected the cells against cisplatin-induced apoptosis. The protective effect of phloretin was abrogated by zinc protoporphyrin IX (ZnPP IX), a HO inhibitor. Furthermore, phloretin pretreatment inhibited mitochondrial dysfunction and the activation of caspases. These results demonstrate that the expression of HO-1 induced by phloretin is mediated by both the JNK pathway and Nrf2; the expression inhibits cisplatin-induced apoptosis in HEI-OC1 cells.

Purpose: The present study was undertaken to elucidate the chemoprotective mechanism of kaempferol, which possesses anti-oxidative and anti-apoptotic properties., Methods: House Ear Institute-Organ of Corti 1 (HEI-OC1) cells were treated with kaempferol in the presence or absence of cisplatin. Cisplatin-induced oxidative stress was assessed by analysis of Comet assay, DNA-laddering assay and activation of caspases. Heme oxygenase-1 (HO-1), mitogen-activated protein kinase (MAPK) pathway and nuclear factor-E2-related factor 2 (Nrf2) were measured by Western blot analysis. Transfection of small interfering RNAs (siRNA), glutathione (GSH) assay and RT-PCR were performed in this study., Results: Kaempferol protected cells against cisplatin-induced apoptosis in a dose-dependent manner in HEI-OC1 cells. Kaempferol-induced HO-1 expression protected against cell death though the c-Jun N-terminal kinase (JNK) pathway and by the aid of Nrf2 translocation. Kaempferol increased the cellular level of GSH and the expression of GCLC time-dependently. siRNA GCLC blocked the increase of GSH level by kaempferol and the protective effect of kaempferol against cisplatin-induced cell death., Conclusion: The expression of HO-1 by kaempferol inhibits cisplatin-induced apoptosis in HEI-OC1 cells, and the mechanism of protective effect is also associated with its inductive effect of GCLC expression.

The correlation of c-Myc expression with resveratrol-induced turnover of medulloblastoma cells was investigated in this study by checking (1) c-Myc expression in medulloblastoma tissues and cell lines (UW228-2 and UW228-3), (2) the in vitro effect of resveratrol on c-Myc expression and (3) the influences of c-Myc inhibition in cell growth and survival. Immunohistochemical staining of human medulloblastomas and noncancerous cerebellar tissues revealed that 8 out of 11 tumor tissues (72.7%) expressed c-Myc, in which 4 cases (50%) showed intensified nuclear labeling. RT-PCR, Western blotting, immunocytochemical and immunofluorescence stainings revealed c-Myc downregulation accompanied with growth suppression and apoptosis. Flow cytometry analysis showed S phase arrest in resveratrol-treated cell populations. Transfection of c-Myc directed antisense oligonucleotides to the cultured medulloblastoma cells could reduce c-Myc expression, inhibit cell growth and arrest the cell cycle at S phase. Our results thus for the first time demonstrate that c-Myc downregulation is a critical molecular event of resveratrol-mediated anti-medulloblastoma activity, which is closely associated with growth suppression, cell cycle arrest and apoptosis of medulloblastoma cells.

Background & Objective: Cigarette smoke exposure has been reported to induce DNA damage in a variety of cell types. This study was to investigate DNA damage and apoptosis in normal human bronchial epithelial cell line NHBE and lung carcinoma cell line SPC-A1 caused by cigarette smoke extract., Methods: NHBE and SPC-A1 cells were incubated with different concentrations of cigarette smoke extract. Cell viability was evaluated by MTT assay. Fluorescence-labeled anti-histone gamma-H2AX polyclonal antibody was used to detect DNA double-strand breaks (DSBS) in chromatin. DNA damage was analyzed by flow cytometry. The expression of gamma-H2AX was detected by Western blot. Cigarette smoke extract-induced cell apoptosis was detected by sub G1 peak method and annexin V-FITC/propidium iodide (PI) staining assay. Cell morphology of DNA damage and apoptosis was observed by confocal laser microscopy., Results: MTT assay results showed that cigarette smoke extract decreased the viability of NHBE and SPC-A1 cells in time-and concentration-dependent manners. Cigarette smoke extract induced DSBS in NHBE cells and SPC-A1 cells, and led to H2AX phosphorylation (denoted gamma-H2AX) in time-and concentration-dependent manners. The maximal value of gamma-H2AX was seen about 4 h after the treatment, and the value decreased subsequently, but did not reduce to a normal level. Cell apoptosis appeared about 12 h after DNA damage. Cigarette smoke extract also initiated the accumulation of gamma-H2AX in these cells, and cell apoptosis morphology was observed 4 h later., Conclusion: Cigarette smoke extract can induce DSBS and apoptosis in NHBE and SPC-A1 cells in time-and concentration-dependent manners.

Resveratrol has tumor-suppressive activities in some in vitro and in vivo experimental systems but its effect on medulloblastoma cells is still unknown. In this study, resveratrol was used to treat four human medulloblastoma cell lines (Med-3, UW228-1, -2 and -3) and its effects on cell growth, differentiation and death were examined by multiple approaches. Expression of Fas, FasL and caspase-3 in the cells without and with resveratrol treatments was examined by immunocytochemical staining and mRNA in situ hybridization and the influence of anti-Fas antibody (200 ng/ml) in cell growth and survival was determined as well. The results demonstrated that resveratrol could suppress growth, promote differentiation and commit its target cells to apoptosis in time- and dose-related fashions. Fas was constitutively expressed but FasL was undetectable in the four lines in spite of resveratrol treatment. Anti-Fas antibody (200 ng/ml) neither inhibited growth nor induced apoptosis of those cell lines. Up-regulated caspase-3 was found in resveratrol-treated populations and appearance of its cleaved form was closely associated with the apoptotic event. These findings suggest for the first time that resveratrol is an effective anti-medulloblastoma agent that kills medulloblastoma cells through a Fas-independent pathway.

Adjuvant chemotherapies have been used to prevent recurrence of bladder transitional cell carcinoma (TCC), but their efficacies are variable due to the side effects of anti-cancer agents and the drug resistant property of the target cells. To provide experimental evidence for improving clinical management of TCCs, two human TCC cell lines, EJ and BIU, were treated for 1 or 2 h by 50, 100, 150 and 200 micro g/ml, respectively and their growth and death patterns were elucidated in 12-h intervals. The status of Fas, FasL and caspase-3 in the two cell lines were analyzed with immunocytochemical staining and Western blot hybridization, and their potential link to MMC-induced cell death was investigated by treating the cells with anti-Fas antibody (150 ng/ml) and by incubating the cells with an inhibitor of caspase-3 related proteases Ac-DEVO-CHO (250 micro M) 1 h before 100 micro g/ml MMC treatment. The results demonstrated that the lower dose (100 micro g/ml) and short-term (1 h) MMC treatment could induce sufficient apoptosis in EJ and BIU populations within 48 or 60 h. Constitutive soluble and membrane Fas and FasL were found in both cell lines, and caspase-3 could be upregulated after MMC treatment. Anti-Fas antibody could commit the target cells to die of apoptosis, while Ac-DEVD-CHO inhibited MMC-induced apoptosis. Our data thus suggest that MMC-induced apoptosis in EJ and BIU cells is mediated by Fas and upregulation and activation of caspase-3 is an essential element for the apoptotic process. Reduced dose and short-term MMC strategy would be of practical value either in determining the apoptotic susceptibility of individual TCC cases or in the clinical instillation of urothelial cancers.

Curcumin is a polyphenolic compound derived from the plant turmeric and the structural instability of which limits its further clinical applications. In this study, 11 curcumin analogs with more stable scaffold were prepared and evaluated. The results indicated that the optimal compound Y-11 exhibited the strongest antiproliferative activities against lung cancer cells including H460 and H1650. Further studies showed that Y-11 potentially inhibited hDHODH, induced cell cycle arrest and apoptosis as well as down-regulated crucial signal pathway protein expression in H1650 cells. In the conclusion, the newly designed curcumin analog Y-11 may be suitable for further development in lung cancer treatment. [ABSTRACT FROM AUTHOR]

Abstract: Medulloblastoma cells exhibit varied responses to therapy by all-trans retinoic acid (RA). The underlying mechanism for such diverse effects however remains largely unclear. In this study, we attempted to elucidate the molecular basis of RA resistance through the study of RA signaling components in both RA-sensitive (Med-3) and RA-resistant (UW228-2 and UW228-3) medulloblastoma cells. The results revealed that RARα/β/γ and RXRα/β/γ were found in the three cell lines. Expression of CRABP-I and CRABP-II was seen in Med-3 cells, up-regulated when treated with RA, but was absent in UW228-2 and UW228-3 cells regardless of RA treatment. Bisulfite sequencing revealed 8 methylated CG sites at the promoter region of CRABP-II in UW228-2 and UW228-3 but not in Med-3 cells. Demethylation by 5-aza-2′-deoxycytidine recovered CRABP-II expression. Upon restoration of CRABP-II expression, both UW228-2 and UW228-3 cells responded to RA treatment by forming neuronal-like differentiation, synaptophysin expression, β-III tubulin upregulation, and apoptosis. Furthermore, CRABP-II specific siRNA reduced RA sensitivity in Med-3 cells. Tissue microarray-based immunohistochemical staining showed variable CRABP-II expression patterns among 104 medulloblastoma cases, ranging from negative (42.3%), partly positive (14.4%) to positive (43.3%). CRABP-II expression was positively correlated with synaptophysin (rs = 0.317; p = 0.001) but not with CRABP-I expression (p > 0.05). In conclusion, aberrant methylation in CRABP-II reduces the expression of CRABP-II that in turn confers RA resistance in medulloblastoma cells. Determination of CRABP-II expression or methylation status may enable a personalized RA therapy in patients with medulloblastomas and other types of cancers. [Copyright &y& Elsevier]

The correlation of c-Myc expression with resveratrol-induced turnover of medulloblastoma cells was investigated in this study by checking (1) c-Myc expression in medulloblastoma tissues and cell lines (UW228-2 and UW228-3), (2) the in vitro effect of resveratrol on c-Myc expression and (3) the influences of c-Myc inhibition in cell growth and survival. Immunohistochemical staining of human medulloblastomas and noncancerous cerebellar tissues revealed that 8 out of 11 tumor tissues (72.7%) expressed c-Myc, in which 4 cases (50%) showed intensified nuclear labeling. RT-PCR, Western blotting, immunocytochemical and immunofluorescence stainings revealed c-Myc downregulation accompanied with growth suppression and apoptosis. Flow cytometry analysis showed S phase arrest in resveratrol-treated cell populations. Transfection of c-Myc directed antisense oligonucleotides to the cultured medulloblastoma cells could reduce c-Myc expression, inhibit cell growth and arrest the cell cycle at S phase. Our results thus for the first time demonstrate that c-Myc downregulation is a critical molecular event of resveratrol-mediated anti-medulloblastoma activity, which is closely associated with growth suppression, cell cycle arrest and apoptosis of medulloblastoma cells. [ABSTRACT FROM AUTHOR]

Abstract: Background: Caspase-3 is a critical apoptosis-promoting element but its status during stepwise gastrocarcinogenesis needs to be further clarified. Materials and methods: By the use of frozen tissue microarrays constructed with the tissue spots cored from defined histological regions in tissue blocks, the pattern of caspase-3 expression in noncancerous, premalignant (atrophic gastritis and intestinal metaplasia) tissue and cancer spots were analyzed under the same experimental conditions by the methods of immunohistochemistry and mRNA-in situ hybridization. Results: Caspase-3 was expressed in all 34 of the noncancerous mucosa (100%), in 16 of the 17 premalignant tissues (94.1%) and in 15 of the 48 gastric cancers (31.3%). The incidences of caspase-3 detection were significantly different (p <0.01) between noncancerous mucosa and intestinal as well as diffuse gastric cancers. Conclusion: Down-regulated caspase-3 is closely correlated with gastric cancer formation and would be a potential indicator of tumor formation and progression. Helicobacter pylori (H. pylori; Hp) infection is but not the only one element responsible to the enhanced caspase-3 expression in gastric epithelia. [Copyright &y& Elsevier]

Poly(ADP-ribose)polymerase (PARP)1/2 inhibitors have been proved to be clinically effective anticancer drugs. Here we report a new PARP1/2 inhibitor, simmiparib, displaying apparently improved preclinical anticancer activities relative to the first approved inhibitor olaparib. Simmiparib inhibited PARP1/2 approximately 2-fold more potently than olaparib, with more than 90-fold selectivity over the other tested PARP family members. Simmiparib and olaparib caused similar cellular PARP1-DNA trapping. Simmiparib selectively induced the accumulation of DNA double-strand breaks, G2/M arrest and apoptosis in homologous recombination repair (HR)-deficient cells. Consistently, simmiparib showed 26- to 235-fold selectivity in its antiproliferative activity against HR-deficient cells over the corresponding isogenic HR-proficient cells. Notably, its antiproliferative activity was 43.8-fold more potent than that of olaparib in 11 HR-deficient cancer cell lines. Simmiparib also potentiated the proliferative inhibition of several conventional anticancer drugs. Simmiparib reduced the poly(ADP-ribose) formation in HR-deficient cancer cells and xenografts. When orally administered to nude mice bearing xenografts, simmiparib revealed excellent pharmacokinetic properties. Simmiparib caused approximately 10-fold greater growth inhibition than olaparib against HR-deficient human cancer cell- or tissue-derived xenografts in nude mice. Collectively, these findings support the undergoing clinical trials of simmiparib. [ABSTRACT FROM AUTHOR]

Grifolin, a secondary metabolite isolated from the fresh fruiting bodies of the mushroom Albatrellus confluens, has been shown to inhibit the growth of some cancer cell lines in vitro by induction of apoptosis in previous studies of our group. However, the mechanisms of action are not completely understood. An apoptosis-related gene expression profiling analysis provided a clue that death-associated protein kinase 1 (dapk1) gene was upregulated at least twofold in response to grifolin treatment in nasopharyngeal carcinoma cell CNE1. Here, we further investigated the role of DAPK1 in apoptotic effect induced by grifolin. We observed that protein as well as mRNA level of DAPK1 was induced by grifolin in a dose-dependent manner in nasopharyngeal carcinoma cell CNE1. We found that grifolin increased both Ser392 and Ser20 phosphorylation levels of transcription factor p53 protein, which could promote its transcriptional activity. Moreover, induced by grifolin, the recruitment of p53 to dapk1 gene promoter was confirmed to enhance markedly using EMSA and ChIP assays analysis. The involvement of DAPK1 in grifolin-induced apoptosis was supported by the studies that introducing siRNA targeting DAPK1 to CNE1 cells remarkably interfered grifolin-caused apoptotic effect as well as the activation of caspase-3. Grifolin induced upregulation of DAPK1 via p53 was also observed in tumour cells derived from human breast cancer and human colon cancer. The findings suggest that upregulation of DAPK1 via p53–DAPK1 pathway is an important mechanism of grifolin contributing to its ability to induce apoptotic effect. Since growing evidence found a significant loss of DAPK1 expression in a large variety of tumour types, grifolin may represent a promising candidate in the intervention of cancer via targeting DAPK1. [Copyright &y& Elsevier]

Abstract: Altered Notch signaling seems linked with medulloblastoma (MB) formation and resveratrol exhibits anti-medulloblastoma effects. However, the influence of resveratrol in Notch signaling of MB cells has not been described. This issue was addressed here by checking Notch1 and Notch2 statuses in three MB cell lines with and without resveratrol treatment. Notch1 and Notch2 were detected in the cytoplasm of three cell lines under normal condition, which were up-regulated by resveratrol along with differentiation, apoptosis and enhanced Hes1 nuclear translocation. Nevertheless, blockage of Notch enzymatic cleavage with γ-seacretase inhibitors, DAPT and L-685,458, neither interrupted resveratrol-caused cellular events nor affected MB cell growth. These results demonstrate that Notch signaling has little relevance with resveratrol-induced differentiation and apoptosis and may not be a universal critical factor of MB cells. [Copyright &y& Elsevier]

Abstract: Resveratrol induces apoptosis and regulates CYP1A1 and CYP1B1 expression in human medulloblastoma cells. To elucidate the potential correlation of their expressions with the anti-medulloblastoma effects of resveratrol, human medulloblastoma cells, UW228-3, were treated with CYP1A1 selective inhibitor (alpha-naphthoflavone, α-NF), selective CYP1A1/1A2 inducer (beta-naphthoflavone, β-NF) and their combination with resveratrol, respectively. The influences of those treatments on the expressions of CYP1A1, 1A2 and 1B1 as well as the cell growth, differentiation and death were analyzed. It was found that neither α-NF nor β-NF had any effect on cell growth. α-NF inhibited resveratrol-induced CYP1A1 expression without interfering cell differentiation and apoptosis. β-NF could up-regulate resveratrol-induced CYP1A1 expression but not enhance the anti-cancer effects of resveratrol. CYP1A2 was undetectable in the cells irrespective to the treatments. Aryl hydrocarbon receptor (AhR) was absent in UW228-3 cells under normal culture and treated with resveratrol but induced by both α- and β-NF. Immunohistochemical examination performed on 11 pairs of human medulloblastoma and noncancerous cerebellar tissues revealed that AhR was undetectable in either of them, whereas CYP1A1 was expressed in cerebellum but down-regulated or diminished in their malignant counterparts. Our data suggest for the first time that CYP1A1 and 1B1 expressions in human medulloblastoma cells are AhR-independent and have no direct links with resveratrol-induced differentiation and apoptosis. Appearance of CYP1A1 expression may reflect a more maturated status and a better prognosis of medulloblastomas. [Copyright &y& Elsevier]

Resveratrol induces differentiation and Fas-independent apoptosis of medulloblastoma cells by a largely unknown mechanism. CYP1A1 and 1B1 are involved in resveratrol-mediated tumor suppression but their expression in medulloblastoma cells and their relevance to anti-medulloblastoma activity of resveratrol have not been described. The statuses of CYP1A1 and 1B1 in UW228-3 medulloblastoma cells without and with resveratrol treatments were elucidated in this study with ethoxyresorufin O-deethylation assay, followed by RT-PCR, immunocytochemical staining and Western blot hybridization. CYP1A1/1B1 enzymatic activity was low in UW228-3 cells but became several folds higher upon resveratrol treatments. CYP1A1 was undetectable and CYP1B1 was expressed in normally cultured cells. Accompanied by the increased fraction of apoptosis, enhanced CYP1A1 and downregulated CYP1B1 were observed in resveratrol-treated cells in time- and dose-related fashions. Our results demonstrate for the first time that in the medulloblastoma cell system, CYP1A1 upregulation is paralleled with resveratrol-induced differentiation and apoptosis, while CYP1B1 may not be an essential element in metabolic activation of resveratrol in those cells. CYP1A1 and 1B1 are resveratrol response genes and potential chemosensitive markers of medulloblastoma cells. [Copyright &y& Elsevier]