Inhibition of Myeloid Cell Leukemia 1 and Activation of Caspases Are Critically Involved in Gallotannin‐induced Apoptosis in Prostate Cancer Cells

Although gallotannin contained in several medicinal plants was known to have multi‐biological activities, such as antioxidant, antiinflammatory, antimicrobial, immunomodulatory, and antitumor effects, the underlying apoptotic mechanism of gallotannin is not fully understood so far. Thus, in the present study, the apoptotic mechanism of gallotannin was elucidated in DU145, PC‐3, and M2182 prostate cancer cells in association with myeloid cell leukemia 1 (Mcl‐1) signaling. Gallotannin exerted dose‐dependent cytotoxicity in DU145, PC‐3, and M2182 prostate cancer cells. Also, gallotannin showed apoptotic morphological features and increased the number of terminal deoxynucleotidyl transferase dUTP nick end labeling positive cells and sub‐G1 accumulation in three prostate cancer cell lines. Consistently, gallotannin cleaved poly (ADP‐ribose) polymerase (PARP) and attenuated the expression of procaspases 9 and 3 in three prostate cancer cell lines. Furthermore, gallotannin attenuated the expression of survival genes such as Mcl‐1, B‐cell lymphoma 2, and B‐cell lymphoma 2 extra large in three prostate cancer cell lines. Interestingly, overexpression of Mcl‐1 reversed the ability of gallotannin to cleave PARP and increase sub‐G1 population in three prostate cancer cell lines. Conversely, silencing of Mcl‐1 enhanced apoptosis by gallotannin in three prostate cancer cell lines by FACSCalibur (Becton Dickinson, Franklin Lakes, NJ, USA). Taken together, our findings demonstrate that inhibition of Mcl‐1 and activation of caspases are critically involved in gallotannin‐induced apoptosis in prostate cancer cells. Copyright © 2015 John Wiley & Sons, Ltd.     

Apoptotic Effect of Galbanic Acid via Activation of Caspases and Inhibition of Mcl‐1 in H460 Non‐Small Lung Carcinoma Cells

Galbanic acid (GBA), a major compound of Ferula assafoetida, was known to have cytotoxic, anti‐angiogenic and apoptotic effects in prostate cancer and murine Lewis lung cancer cells; the underling apoptotic mechanism of GBA still remains unclear so far. Thus, in the present study, the apoptotic mechanism of GBA was investigated mainly in H460 non‐small cell lung carcinoma (NSCLC) cells because H460 cells were most susceptible to GBA than A549, PC‐9 and HCC827 NSCLC cells. Galbanic acid showed cytotoxicity in wild EGFR type H460 and A549 cells better than other mutant type PC‐9 and HCC827 NSCLC cells. Also, GBA significantly increased the number of Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) positive cells and sub G1 population in H460 cells. Western blotting revealed that GBA cleaved poly (ADP‐ribose) polymerase (PARP), activated Bax and caspase 9, attenuated the expression of Bcl‐2, Bcl‐x_L, and Myeloid cell leukemia 1 (Mcl‐1) in H460 cells. However, interestingly, overexpression of Mcl‐1 blocked the ability of GBA to exert cytotoxicity, activate caspase9 and Bax, cleave PARP, and increase sub G1 accumulation in H460 cells. Overall, these findings suggest that GBA induces apoptosis in H460 cells via caspase activation and Mcl‐1 inhibition in H460 cells as a potent anticancer agent for NSCLC treatment. Copyright © 2015 John Wiley & Sons, Ltd.     

Pseudolaric Acid B Induces Caspase‐Dependent Apoptosis and Autophagic Cell Death in Prostate Cancer Cells

Previous studies have shown that Pseudolaric acid B (PAB), a medicinal plant‐derived terpenoid, is a promising chemopreventive or therapeutic agent against various types of cancer. However, less is known regarding its activity against prostate cancer. The objective of the current study is designed to determine the anti‐prostate cancer effects of PAB. We demonstrated here that PAB was highly effective against both androgen‐dependent (LNCaP) and androgen‐independent prostate cancer cells (PC‐3 and DU145) through the mechanisms involved in induction of G2/M cell cycle arrest, caspase‐dependent apoptosis and autophagic cell death. Furthermore, PAB can greatly sensitize these two aggressive androgen‐independent prostate cancer cells to ABT‐737‐induced cytotoxicity. Our findings suggest that PAB holds excellent potential as either novel chemopreventive agent or enhancer of therapeutic drug against prostate cancer. Copyright © 2012 John Wiley & Sons, Ltd.     

Capsaicin suppressed activity of prostate cancer stem cells by inhibition of Wnt/β‐catenin pathway

Cancer stem cells (CSCs) are considered as the origin and driving cells of cancer, and play a key role in the progress of cancer. Studies have shown that capsaicin exerted inhibitory effect on prostate cancer cells, however, the effects of capsaicin on prostate CSCs remain undefined. In the present study, we showed that capsaicin could downregulate prostate CSCs markers and inhibit the growth of PC‐3 and DU145 prostate cancer stem cells. Further, we found capsaicin suppressed the expression of Wnt‐2, p‐GSK3β and β‐catenin, along with downregulation of Wnt/β‐catenin pathway target genes c‐myc and cyclinD1. Using LiCl, a activator of Wnt/β‐catenin pathway, we found activation of Wnt/β‐catenin pathway could ameliorate the downregulation of prostate CSCs markers and the growth inhibition induced by capsaicin in prostate cancer stem cells. Those data suggested that the inhibition effect of capsaicin on prostate cancer stem cells and the anti‐cancer effect of capsaicin on prostate cancer stem cell may be mediated by Wnt/β‐catenin pathway. Findings from this study reveals for the first time the potential role and mechanisms of capsaicin on prostate cancer stem cells.     

Apoptotic Effect of Astragalin in Melanoma Skin Cancers via Activation of Caspases and Inhibition of Sry‐related HMg‐Box Gene 10

Though Astragalin (kaempferol‐3‐glucoside) contained in Paeonia lactiflora and other plants was known to have anti‐oxidant, antiinflammatory, and anti‐tumor activity, the anti‐tumor mechanism of Astragalin has never been reported in melanomas until now. Thus, in the present study, the underlying apoptotic mechanism of Astragalin isolated from Aceriphyllum rossii was elucidated in A375P and SK‐MEL‐2 melanoma cells. Astragalin exerted cytotoxicity in A375P and SK‐MEL‐2 cells in a concentration‐dependent manner. Also, Astragalin significantly increased the number of TdT‐mediated dUTP nick end labeling positive cells and sub‐G1 population as a feature of apoptosis in A375P and SK‐MEL‐2 cells compared with untreated control. Consistently, western blotting revealed that Astragalin activated caspase 9/3 and Bax, cleaved poly (ADP‐ribose) polymerase, and attenuated the expression of cyclin D1, Mcl‐1, and Sry‐related HMg‐Box gene 10 (SOX10) in A375P and SK‐MEL‐2 cells. Of note, ectopic expression of SOX10 reduced the apoptotic ability of Astragalin to inhibit proliferation, cleave poly (ADP‐ribose) polymerase, and caspase 3 in A375P and SK‐MEL‐2 melanoma cells. Overall, our findings provide evidence that Astragalin induces apoptosis in A375P and SK‐MEL‐2 melanoma cells via activation of caspase9/3 and inhibition of SOX10 signaling. Copyright © 2017 John Wiley & Sons, Ltd.     

Reactive Oxygen Species‐Mediated Activation of AMP‐Activated Protein Kinase and c‐Jun N‐terminal Kinase Plays a Critical Role in Beta‐Sitosterol‐Induced Apoptosis in Multiple Myeloma U266 cells

Although beta‐sitosterol has been well known to have anti‐tumor activity in liver, lung, colon, stomach, breast and prostate cancers via cell cycle arrest and apoptosis induction, the underlying mechanism of anti‐cancer effect of beta‐sitosterol in multiple myeloma cells was never elucidated until now. Thus, in the present study, the role of reactive oxygen species (ROS) in association with AMP‐activated protein kinase (AMPK) and c‐Jun N‐terminal kinase (JNK) pathways was demonstrated in beta‐sitosterol‐treated multiple myeloma U266 cells. Beta‐sitosterol exerted cytotoxicity, increased sub‐G₁ apoptotic population and activated caspase‐9 and ‐3, cleaved poly (ADP‐ribose) polymerase (PARP) followed by decrease in mitochondrial potential in U266 cells. Beta‐sitosterol promoted ROS production, activated AMPK, acetyl‐CoA carboxylase (ACC) and JNK in U266 cells. Also, beta‐sitosterol attenuated the phosphorylation of AKT, mammalian target of rapamycin and S6K, and the expression of cyclooxygenase‐2 and VEGF in U266 cells. Conversely, AMPK inhibitor compound C and JNK inhibitor SP600125 suppressed apoptosis induced by beta‐sitosterol in U266 cells. Furthermore, ROS scavenger N‐acetyl L‐cysteine attenuated beta‐sitosterol‐mediated sub‐G₁ accumulation, PARP cleavage, JNK and AMPK activation in U266 cells. Overall, these findings for the first time suggest that ROS‐mediated activation of cancer metabolism‐related genes such as AMPK and JNK plays an important role in beta‐sitosterol‐induced apoptosis in U266 multiple myeloma cells. Copyright © 2013 John Wiley & Sons, Ltd.     

Brassinin Combined with Capsaicin Enhances Apoptotic and Anti‐metastatic Effects in PC‐3 Human Prostate Cancer Cells

Brassinin (BSN), a type of indole compound derived from cruciferous vegetables, has shown anti‐cancer effects in cells and animals. Capsaicin (CAP), an alkaloid derived from the chilli pepper, is also of interest in for its reported efficacy against various malignancies. The objective of our study was to analyze the potential synergistic anti‐tumor effects of BSN combined with CAP on prostate cancer PC‐3 cells. After treatment with BSN and CAP at various concentrations, the synergistic cytotoxic effect of PC‐3 cells was analyzed by MTT method, proliferation, apoptosis, mitochondrial membrane potential, colony formation, and Western blotting. Moreover, the inhibitory effects of BSN and CAP on the constitutive expressions of MMP‐9/2, their enzymatic activities, cellular migration, and cell invasion were also investigated. The cytotoxicity was synergistically increased in combination compared with the single drug used; moreover, proliferation, apoptosis, mitochondrial membrane potential, and colony formation were significantly suppressed and anti‐apoptotic‐, proliferative‐, and metastatic‐related proteins were clearly abolished in the combination group. Besides, constitutive MMP‐9/2 expression, their enzymatic activities, cell migration, and tumor cell invasion were inhibited, and TIMP‐1 was up‐regulated in the combination group in PC‐3 cells. Our results indicate, for the first time, that BSN and CAP in combination exert synergistic anticancer effects in prostate carcinoma. Copyright © 2015 John Wiley & Sons, Ltd.     

Brassinin Induces Apoptosis in PC‐3 Human Prostate Cancer Cells through the Suppression of PI3K/Akt/mTOR/S6K1 Signaling Cascades

The oncogenic PI3K/Akt/mammalian target of rapamycin (mTOR) signaling axis and its downstream effector, the ribosomal protein S6 kinase 1 (S6K1) play a key role in mediating cell survival in various tumor cells. Here, we investigated the effects of brassinin (BSN), a phytoalexin first identified as a constituent of cabbage, on the PI3K/Akt/mTOR/S6K1 activation, cellular proliferation, and apoptosis in PC‐3 human prostate cancer. BSN exerted a significant dose‐dependent cytotoxicity and reduced constitutive phosphorylation of Akt against androgen‐independent PC‐3 cells as compared to androgen‐dependent LNCaP cells. Moreover, knockdown of androgen receptor (AR) by small interfering RNA enhanced the potential effect of BSN on induction of apoptosis in LNCaP cells. BSN clearly suppressed the constitutive activation of PI3K/Akt/mTOR/S6K1 signaling cascade, which correlated with the induction of apoptosis as characterized by accumulation of cells in subG1 phase, positive Annexin V binding, TUNEL staining, loss of mitochondrial membrane potential, down‐regulation of antiapoptotic and proliferative proteins, activation of caspase‐3, and cleavage of PARP. Additionally, BSN could block broad‐spectrum inhibition of PI3K/Akt/mTOR/S6K1 axes, and aberrant Akt activation by pcDNA3‐myr‐HA‐Akt1 plasmid could not prevent the observed suppressive effect of BSN on constitutive mTOR activation. Finally, overexpression of Bcl‐2 also attenuated BSN‐mediated apoptosis in PC‐3 cells. Taken together, our findings suggest that BSN can interfere with multiple signaling cascades involved in tumorigenesis and might be provided as a potential therapeutic candidate for both the prevention and treatment of prostate cancer. Copyright © 2013 John Wiley & Sons, Ltd.     

Activation of Caspase‐9/3 and Inhibition of Epithelial Mesenchymal Transition are Critically Involved in Antitumor Effect of Phytol in Hepatocellular Carcinoma Cells

This study was designed to investigate the antitumor mechanism of Phytol in hepatocellular carcinomas including Huh7 and HepG2 cells in association with caspase dependent apoptosis and epithelial mesenchymal transition (EMT) signaling. Phytol significantly suppressed the viability of Huh7 and HepG2 cells. Also, Phytol significantly increased the sub G1 population and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL) positive cells in a concentration dependent manner in Huh7 and HepG2 cells. Consistently, Phytol cleaved poly (adenosine diphosphate‐ribose) polymerase (PARP), activated caspase‐9/3, and Bax attenuated the expression of survival genes such as Bcl‐2, Mcl‐1, and c‐Myc in Huh7 and HepG2 cells. Of note, Phytol also suppressed typical morphology change of EMT such as loss of cell adhesion and formation of fibroblast like mesenchymal cells in HepG2 cells. Furthermore, Phytol also reversed the loss of E‐cadherin and overexpression of p‐smad2/3, alpha‐smooth muscle actin, and Snail induced by EMT promoter transforming growth factor beta1 in HepG2 cells. Overall, our findings suggest that Phytol exerts antitumor activity via apoptosis induction through activation of caspas‐9/3 and inhibition of EMT in hepatocellular carcinoma cells as a potent anticancer candidate for liver cancer treatment. Copyright © 2015 John Wiley & Sons, Ltd.     

6‐Acetoxy Cyperene,a Patchoulane‐type Sesquiterpene Isolated from Cyperus rotundus Rhizomes Induces Caspase‐dependent Apoptosis in Human Ovarian Cancer Cells

Cyperus rotundus (Cyperaceae) has been widely used in traditional medicine for the treatment of various diseases, including cancer. Although an anti‐tumour effect has been suggested for C. rotundus, the anti‐tumour effects and underlying molecular mechanisms of its bioactive compounds are poorly understood. The n‐hexane fraction of an ethanol extract of C. rotundus rhizomes was found to inhibit cell growth in ovarian cancer (A2780, SKOV3 and OVCAR3) and endometrial cancer (Hec1A and Ishikawa) cells. Among the thirteen sesquiterpenes isolated from the n‐hexane fraction, some patchoulane‐type compounds, but not eudesmane‐type compounds, showed moderate cytotoxic activity in human ovarian cancer cells. In particular, the patchoulane sesquiterpene 6‐acetoxy cyperene had the most potent cytotoxicity. In this regard, propidium iodide/Annexin V staining and terminal deoxynucleotidyl transferase dUTP (deoxynucleotide triphosphate) nick end labeling assay were performed to study cell cycle progression and apoptosis. 6‐acetoxy cyperene induced apoptosis, as shown by the accumulation of sub‐G1 and apoptotic cells. Furthermore, treatment with 6‐acetoxy cyperene stimulated the activation of caspase‐3, caspase‐8 and caspase‐9 and poly(ADP‐ribose)polymerase in a dose‐dependent manner. Pretreatment with caspase inhibitors neutralized the pro‐apoptotic activity of 6‐acetoxy cyperene. Taken together, these data suggest that 6‐acetoxy cyperene, a patchoulane‐type sesquiterpene isolated from C. rotundus rhizomes, is an anti‐tumour compound that causes caspase‐dependent apoptosis in ovarian cancer cells. Copyright © 2015 John Wiley & Sons, Ltd.     

Artocarpus altilis (Parkinson) Fosberg Extracts and Geranyl Dihydrochalcone Inhibit STAT3 Activity in Prostate Cancer DU145 Cells

Artocarpus altilis (Parkinson) Fosberg has traditionally been used in Indonesia for the treatment of liver cirrhosis, hypertension, and diabetes. In many other countries, it is used for the treatment of malaria, yellow fever, and dengue fever. It has been reported that A. altilis extracts have antiatherosclerotic and cytoprotective effects, but its molecular targets in tumor cells are not yet fully understood. The A. altilis extracts and the partially purified fraction have been shown to inhibit STAT3 activity and the phosphorylation of STAT3 in a dose‐dependent manner. To identify the active components, a bioassay‐guided isolation of the partially purified fraction resulted in the identification of a geranyl dihydrochalcone, CG901. Its chemical structure was established on the basis of spectroscopic evidence and comparison with published data. The partially purified fraction and the isolated a geranyl dihydrochalcone, CG901, down‐regulated the expression of STAT3 target genes, induced apoptosis in DU145 prostate cancer cells via caspase‐3 and PARP degradation, and inhibited tumor growth in human prostate tumor (DU145) xenograft initiation model. These results suggest that A. altilis could be a good natural source and that the isolated compound will be a potential lead molecule for developing novel therapeutics against STAT3‐related diseases, including cancer and inflammation. Copyright © 2015 John Wiley & Sons, Ltd.     

Pachymic Acid Induces Apoptosis of EJ Bladder Cancer Cells by DR5 Up‐Regulation,ROS Generation,Modulation of Bcl‐2 and IAP Family Members

Pachymic acid (PA) is a lanostane‐type triterpenoid derived from Poria cocos mushroom that possess various biological effects such as anti‐cancer, antiinflammatory and anti‐metastasis effects. In this study, we investigated the anti‐cancer effects of PA in EJ bladder cancer cells. The results showed that PA significantly inhibited proliferation of EJ cells in a dose‐dependent manner. PA induced accumulation of sub‐G1 DNA content (apoptotic cell population), apoptotic bodies and chromatin condensation and DNA fragmentation in EJ cells in a dose‐dependent manner. PA also induces activation of caspase‐3, ‐8 and ‐9, and subsequent cleavage of poly (ADP‐ribose) polymerase, and significantly suppressed the inhibitor of apoptosis protein family proteins in a dose‐dependent manner. Furthermore, PA activates Bid and induced the loss of mitochondrial membrane potential (ΔΨ_m) with up‐regulated pro‐apoptotic proteins (Bax and Bad), down‐regulated anti‐apoptotic proteins (Bcl‐2 and Bcl‐xL) and cytochrome c release. In turn, PA increased the generation of reactive oxygen species (ROS); also, the ROS production was blocked by N‐acetyl‐L‐cysteine. The expressions of TNF‐related apoptosis inducing ligand and death receptor 5 were up‐regulated by PA in a dose‐dependent manner, suggesting extrinsic pathway also involved in PA‐induced apoptosis. This study provides evidence that PA might be useful in the treatment of human bladder cancer. Copyright © 2015 John Wiley & Sons, Ltd.     

广藿香醇对人雄激素非依赖性前列腺癌细胞DU145生长的抑制作用及机制

目的:观察广藿香醇(pachouli alcohol,PA)对人雄激素非依赖性前列腺癌细胞DU145的凋亡诱导效应及增殖抑制作用,探讨其发生机制。方法:广藿香醇10,20,40,80,160 mg·L-1作用在密度为6×107/L DU145细胞24,48,72 h后,采用四甲基偶氮唑盐法(MTT)检测广藿香醇对细胞的生长抑制作用;透射电镜观察药物诱导细胞凋亡形态变化;Annexin V-FITC,PI双标记法流式细胞仪检测药物诱发细胞凋亡的改变;Western blot检测半胱氨酸天冬氨酸蛋白酶3(Caspase-3)、B细胞淋巴瘤/白血病-2蛋白(Bcl-2)、Bcl-2关联X蛋白(Bax)、凋亡抑制蛋白Livin的表达。结果:MTT法检测提示广藿香醇处理组细胞增殖抑制作用明显,10,20,40,80,160 mg·L-1广藿香醇对DU145的24,48,72 h抑制率分别为5.73%,16.67%,22.61%;13.42%,25.03%,39.68%;25.92%,31.46%,52.76%;39.61%,54.68%,73.52%;56.42%,77.35%,91.58%,呈剂量-时间依赖性(P<0.05)。透射电镜显示药物作用后细胞出现凋亡形态改变。流式细胞仪检测提示广藿香醇作用使细胞凋亡率明显升高,与对照组比较有统计学意义(P<0.05)。Western blot检测提示广藿香醇可增强细胞Caspase-3,Bax的表达,下调Livin,Bcl-2蛋白的表达。结论:广藿香醇能抑制DU145细胞增殖,其作用机制可能与诱导细胞凋亡效应有关。     

Apoptotic Effect of Sanggenol L via Caspase Activation and Inhibition of NF‐κB Signaling in Ovarian Cancer Cells

In the present study, the underlying apoptotic mechanism of sanggenol L was elucidated in ovarian cancer cells. Sanggenol L showed cytotoxic and antiproliferative effect in A2780, SKOV‐3, and OVCAR‐3 ovarian cancer cells in a concentration‐dependent fashion. Consistently, sanggenol L increased sub‐G1 phase population and early and late apoptotic portion in ovarian cancer cells. Also, sanggenol L activated caspase9/3, suppressed the phosphorylation of IκBα and p65 NF‐κB (nuclear factor kappa‐light‐chain‐enhancer of activated B cells), attenuated the expression of Cyclin D1, and cleaved poly(adenosine diphosphate ribose ‐ribose) polymerase in SKOV‐3, A2780, and OVCAR‐3 cells. Furthermore, sanggenol L blocked nuclear translocation of NF‐κB and also attenuated the expression of NF‐κB related genes such as c‐Myc, Cyclin D1, and Bcl‐_XL, Bcl‐2, in lipopolysaccharide‐treated SKOV‐3 cells. Overall, our findings for the first time suggest that sanggenol L induces apoptosis via caspase activation and inhibition of NF‐κB/IκBα phosphorylation as a potent chemotherapeutic agent for ovarian cancers. Copyright © 2015 John Wiley & Sons, Ltd.     

黄芩苷诱导前列腺癌细胞株DU145凋亡的体外研究

目的 :探讨黄芩苷诱导前列腺癌细胞株DU14 5凋亡的作用机制。方法 :采用不同浓度的黄芩苷处理细胞后 ,用流式细胞仪检测前列腺癌细胞DU14 5的凋亡率及细胞周期分布 ;电镜下观察细胞超微结构 ;免疫组织化学染色检测凋亡相关蛋白的表达。结果 :5 0 ,12 5 μmol·L^-1黄芩苷能诱导前列腺癌细胞DU14 5凋亡 ,凋亡率与剂量正相关 ;DU14 5随药物浓度及作用时间变化 ,细胞周期分布呈现G₁期细胞比例逐渐增高 ,并出现典型的凋亡峰 ;电镜下可见特征性的凋亡小体 ;免疫组织化学染色提示bcl 2在药物处理的DU14 5中表达下调 ,Bax表达缺失 ,Fas表达上调。结论 :黄芩苷能诱导前列腺癌细胞凋亡 ,并明显抑制癌细胞增殖 ,具有直接抗肿瘤作用。     

5-氨基水杨酸结肠定位双层包衣微丸的制备

 目的 制备5-氨基水杨酸（5-ASA）果胶壳聚糖聚电解质复合物（PEC）-尤特奇结肠定位双层包衣微丸。方法 扩散实验考察PEC膜对传递系统释药速率的影响;考察PEC包衣微丸在大鼠盲肠内的生物降解性;考察膜溶胀性与阻滞释药能力和生物降解性的关系;制备双层包衣微丸并验证其结肠定位性能。结果 扩散实验表明,在模拟小肠液中阻滞释药能力较强的3种处方为：A、果胶-壳聚糖Ⅰ=3∶1, B、果胶-壳聚糖Ⅰ-HPMC=2∶1∶1,C、果胶-壳聚糖Ⅱ=2∶1;膜降解实验表明PEC包衣微丸能被结肠微生物菌群所降解;溶胀实验显示,膜溶胀比与包衣微丸的释药速率和降解性之间不存在线性关系;模拟胃肠道传输的体外释药实验显示,PEC-尤特奇双层包衣微丸有效地在小肠中阻滞药物释放,在结肠中释药较快,具备双模式的释药特征。结论 5-ASA果胶壳聚糖PEC-尤特奇结肠定位双层包衣具有双模式的释药特征,具有良好的结肠定位性能。     

Cinobufagin,a bufadienolide from traditional Chinese medicine Bufo bufo gargarizans CANTOR,inhibits PC3 cell growth in vitro and in vivo

ObjectiveTo explore the effects of cinobufagin (CBF), an active component of toad venom (Bufo bufo gargarizans CANTOR), on the proliferation and apoptosis of PC3 human prostate cancer cells in vitro and preliminarily investigate the mechanism of CBF in suppressing tumor cell growth in vivo.MethodsThe effect of CBF on PC3 cells proliferation was detected using MTT assay. The morphological changes of PC3 cells were observed under an optical microscope. Colony formation assays were used to observe the CBF effect on colony formation by PC3 cells. PC3 cell apoptosis after treatment with CBF for 48 hours was monitored using flow cytometry. Furthermore, the effect of CBF on the expression of myeloid cell leukemia-1 (MCL-1) and related apoptotic proteins was examined using western blotting. A xenograft model was established in BALB/c nude mice to evaluate the effect of CBF on prostate cancer in vivo.ResultsThe MTT assay results illustrated that PC3 cell proliferation was inhibited in vitro by CBF in a concentration- and time-dependent manner. Compared with the control group findings, CBF significantly inhibited the formation of PC3 cells (P = .005). Flow cytometry revealed that after treatment with 50 nM CBF for 48 hours, the apoptotic rate of PC3 cells was 41.97 (5.16)%, indicating that CBF could significantly induce its apoptosis (P = .003). In addition, optical and fluorescence microscopy uncovered remarkable inhibition of cell proliferation accompanied by morphologic changes. The western blotting result indicated that CBF obviously downregulated the expression of the anti-apoptotic protein MCL-1. Most importantly, CBF reduced the carcinogenicity of PC3 xenografts in nude mice.ConclusionCBF can inhibit the growth of PC3 cells both in vitro and in vivo and induce apoptosis of tumor cells. The corresponding mechanism may be correlated with the activation of caspase family proteins via MCL-1.     

Mechanisms of Andrographolide‐Induced Platelet Apoptosis in Human Platelets: Regulatory Roles of the Extrinsic Apoptotic Pathway

Andrographolide, a novel nuclear factor‐κB (NF‐κB) inhibitor, is isolated from the leaves of Andrographis paniculata. Platelet activation is relevant to a variety of coronary heart diseases. Our recent studies revealed that andrographolide possesses potent antiplatelet activity by inhibition of the p38 MAPK/^●HO‐NF‐κB‐ERK2 cascade. Although platelets are anucleated cells, apoptotic machinery apparatus recently has been found to regulate platelet activation and limit platelet lifespan. Therefore, we further investigated the regulatory effects of andrographolide on platelet apoptotic events. In this study, apoptotic signaling events for caspase‐3, ‐8, and Bid were time (10–60 min)‐ and dose (25–100 μΜ)‐dependently activated by andrographolide in human platelets. Andrographolide could also disrupt mitrochondrial membrane potential. In addition, caspase‐8 inhibitor (z‐IETD‐fmk, 50 μΜ) was found to reverse andrographolide‐induced caspase‐8 activation, whereas the antagonistic anti‐Fas receptor (ZB4, 500 ng/mL) and anti‐tumor necrosis factor‐R1 (H398, 10 µg/mL) monoclonal antibodies did not. In conclusion, this study for the first time demonstrated that andrographolide might limit platelet lifespan by initiating the caspase‐8‐dependent extrinsic apoptotic pathway, in spite of no direct evidence that death receptors are involved in this process proved. Overall, the various medicinal properties of andrographolide suggest its potential value in treating patients with thromboembolic disorders. Copyright © 2012 John Wiley & Sons, Ltd.