PARP inhibitor reduces proliferation and increases apoptosis in breast cancer cells

Objective： Apoptosis is a reliable marker of chemotherapeutic efficacy. Olaparib and paclitaxel inhibit proliferation and induce apoptosis in a variety of cancers. We investigated the effects of paclitaxel combined with olaparib on apoptosis in breast cancer Bcap37 cells. Methods： Proliferation and apoptosis were detected by MTT assay and PI staining. Degradation of procaspase-3 and poly（ADP-ribose） polymerase （PARP） was analyzed by Western blotting. Results： Compared with paclitaxel alone, paclitaxel combined with 100 mg olaparib significantly reduced survival in Bcap37 cells at all tested treatment durations （P〈0.05）; inhibition increased with increasing olaparib dose and treatment time （P〈0.01）. Combined treatment yielded significantly higher rates of apoptosis （P〈0.05）, which also increased with time （P〈0.01）. Fluorescence micrographs showed that early and late apoptotic cells increased with treatment time. Pro-caspase-3 and PARP degradation was induced by paclitaxel and enhanced by olaparib in a dose-dependent manner. Thus, combined treatment was substantially more effective than treatment with paclitaxel alone. Conclusions： Our findings suggest that paclitaxel and olaparib inhibit breast cancer Bcap37 cell proliferation and induce apoptosis. Combined treatment further reduced cell growth and enhanced apoptosis, suggesting that this combination therapy may be a promising treaunent for breast cancer.

Dual targeting of Polo-like kinase 1 and baculoviral inhibitor of apoptosis repeat-containing 5 in TP53-mutated hepatocellular carcinoma

BACKGROUND Hepatocellular carcinoma(HCC),often diagnosed at advanced stages without curative therapies,is the fifth most common malignant cancer and the second leading cause of cancer-related mortality.Polo-like kinase 1(PLK1)is activated in the late G2 phase of the cell cycle and is required for entry to mitosis.Interestingly,PLK1 is overexpressed in many HCC patients and is highly associated with poor clinical outcome.Baculoviral inhibitor of apoptosis repeatcontaining 5(BIRC5)is also highly overexpressed in HCC and plays key roles in this malignancy.AIM To determine the expression patterns of PLK1 and BIRC5,as well as their correlation with p53 mutation status and patient clinical outcome.METHODS The expression patterns of PLK1 and BIRC5,and their correlation with p53 mutation status or patient clinical outcome were analyzed using a TCGA HCC dataset.Cell viability,cell apoptosis,and cell cycle arrest assays were conducted to investigate the efficacy of the PLK1 inhibitors volasertib and GSK461364 and the BIRC5 inhibitor YM155,alone or in combination.The in vivo efficacy of volasertib and YM155,alone or in combination,was assessed in p53-mutated Huh7-derived xenograft models in immune-deficient NSIG mice.RESULTS Our bioinformatics analysis using a TCGA HCC dataset revealed that PLK1 and BIRC5 were overexpressed in the same patient subset and their expression was highly correlated.The overexpression of both PLK1 and BIRC5 was more frequently detected in HCC with p53 mutations.High PLK1 or BIRC5 expression significantly correlated with poor clinical outcome.PLK1 inhibitors(volasertib and GSK461364)or a BIRC5 inhibitor(YM155)selectively targeted Huh7 cells with mutated p53,but not HepG2 cells with wild-type p53.The combination treatment of volasertib and YM155 synergistically inhibited the viability of Huh7 cells via apoptotic pathway.The efficacy of volasertib and YM155,alone or in combination,was validated in vivo in a Huh7-derived xenograft model.CONCLUSION PLK1 and BIRC5 are highly co-expressed in p53-mutated HCC and inhibition of both PLK1 and BIRC5 synergistically compromises the viability of p53-mutated HCC cells in vitro and in vivo.

Human antigen R mediated post-transcriptional regulation of inhibitors of apoptosis proteins in pancreatic cancer

AIM To determine the association of human antigen R(HuR) and inhibitors of apoptosis proteins(IAP1, IAP2) and prognosis in pancreatic cancer.METHODS Protein and mRNA expression levels of IAP1, IAP2 and HuR in pancreatic ductal adenocarcinoma(PDAC) were compared with normal pancreatic tissue. The correlations among IAP1/IAP2 and HuR as well as their respective correlations with clinicopathological parameters were analyzed. The Kaplan-Meier method and log-rank tests were used for survival analysis. Immunoprecipitation assay was performed to demonstrate HuR binding to IAP1, IAP2 mRNA. PANC1 cells were transfected with either anti-HuR siRNA or control siRNA for 72 h and quantitative reverse transcription polymerase chain reaction(RT-PCR), western blot analysis was carried out.RESULTS RT-PCR analysis revealed that HuR, IAP1, IAP2 mRNA expression were accordingly 3.3-fold, 5.5-fold and 8.4 higher in the PDAC when compared to normal pancreas(P < 0.05). Expression of IAP1 was positively strongly correlated with HuR expression(P < 0.05, r = 0.783). Western blot analysis confirmed RTPCR results. High IAP1 expression, tumor resection status, T stage, lymph-node metastases, tumor differentiation grade, perineural and lymphatic invasion were identified as significant factors for shorter survival in PDAC patients(P < 0.05).Immunohistological analysis showed that HuR was mainly expressed in the ductal cancer cell's nucleus and less so in cytoplasm. RNA immunoprecipitation analysis confirmed IAP1 and IAP2 post-transcriptional regulation by HuR protein. Following siHuR transfection, IAP1 mRNA and protein levels were decreased, however IAP2 expression levels were increased.CONCLUSION HuR mediated overexpression of IAP1 significantly correlates with poor outcomes and early progression of pancreatic cancer. Further studies are needed to assess the underlying mechanisms.

SMAC exhibits anti-tumor effects in ECA109 cells by regulating expression of inhibitor of apoptosis protein family

BACKGROUND The poor prognosis and rising incidence of esophageal cancer highlight the need for improved therapeutics that are essential prior to treatment.LCL161 is an SMAC(second mitochondrial activator of caspases)mimic and inhibitor of apoptosis protein(IAP)antagonist which exhibits anti-tumor effects and improves the chemical sensitivity of many cancers.AIM To ascertain the effects and mechanisms of the SMAC analog LCL161 on esophageal cancer cells.METHODS MTT assay and TUNEL assay were used to detect cell proliferation and apoptosis,respectively.Western blot analysis was used to study the molecular mechanisms of LCL161-induced death of ECA109 cells.RESULTS LCL161 decreased ECA109 cell proliferation in dose-and time-dependent manner and induced apoptosis of ECA109 cells in a dose-dependent manner.Also,LCL161 induced a significant decrease in the expression of the XIAP and significant increase in the expression of Caspase-3.In addition,Bax increased significantly with increasing concentrations of LCL161,and the relative expression of Bax was significantly different between groups.CONCLUSION These findings support the hypothesis that LCL161 can inhibit proliferation and induce apoptosis in esophageal cancer cells by regulating the expression of IAP family members,suggesting that it has potential to be an effective treatment for esophageal squamous cell carcinoma.

Expression of second mitochondria-derived activator of caspases, X-linked inhibitor of apoptosis protein, and caspase-3 in pituitary adenomas

Studies concerning correlations between pituitary adenomas and cell apoptosis have mainly focused on upstream apoptosis signaling, but seldom on downstream mediators. In the present study, second mitochondria-derived activator of caspases （Smac）, X-linked inhibitor of apoptosis protein （XIAP）, and caspase-3 protein were qualitatively analyzed using immunohistochemistry, and quantified by western blot. Smac, XIAP, and caspase-3 mRNA expressions were detected by reverse transcription-PCR. Results showed that XIAP protein and mRNA expressions were greater in the invasive pituitary adenoma group compared with the noninvasive pituitary adenoma group. However, Smac and caspase-3 protein and mRNA expressions were lower in the invasive pituitary adenoma group compared with the noninvasive pituitary adenoma group. In the invasive pituitary adenomas, Smac expression was positively correlated with caspase-3 protein and mRNA expression （Protein： r = 0.55, P 0.01; mRNA： r = 0.50, P 0.01）. Smac and caspase-3 expressions were negatively correlated with XIAP protein and mRNA expression （Protein： r = -0.56, -0.64, P 0.01; mRNA： r = -0.69, -0.67, P 0.01）. However, no significant differences in correlation among Smac, XIAP, and caspase-3 were detectable in noninvasive pituitary adenomas. These data indicated that high expression of XIAP and low expression of Smac and caspase-3 suppressed cell apoptosis and led to enhanced invasiveness of pituitary adenomas. Thus, Smac, XIAP, and caspase-3 may be useful markers in determining the invasive behavior of pituitary adenomas.

A novel thioredoxin reductase inhibitor inhibits cell growth and induces apoptosis in HL-60 and K562 cells

Human thioredoxin reductase (TrxR) system is associated with cancer cell growth and anti-apoptosis process. Effects of 1,2-bis(1,2-benzisoselenazolone-3(2H)-ketone)ethane (BBSKE),a novel TrxR inhibitor,were investigated on human leu-kemia cell lines HL-60 and K562. BBSKE treatment induced cell growth inhibition and apoptosis in both cell lines. Apoptosis induced by BBSKE is through Bcl-2/Bax and caspase-3 pathways. Ehrlich's ascites carcinoma-bearing mice were used to inves-tigate the anti-tumor effect of BBSKE in vivo. Tumor-bearing mice treated with BBSKE showed an increase of life span with a comparable effect to cyclophosphamide (CTX). These results suggest a potential usage of BBSKE as a therapeutic agent against non-solid tumors.

Regulatory Effects of X-linked Inhibitor of Apoptosis Protein and Pro-apoptotic Protein Smac on Apoptosis Resistance to Chemotherapy in Pancreatic Cancer Cells~*

Objective： To investigate the relation of X-linked inhibitor of apoptosis （XIAP） and second mitochondria-derived activator of caspase （Smac） signaling pathway to chemoresistance in human pancreatic cancer Panc-1 and BXPC-3 cells. Methods： Apoptosis and the changes of XIAP expression in permeabilized cells induced by cisplatin and 5-fluorouracil （FU） were measured by flow cytometry. The cytosolic expression of XIAP, Smac and caspase-3 was detected by Western blot. A recombinant plasmid vector pEGFP-N1/Smac was constructed and transfected into of Pancol cells. The effect of cytosolic overexpression of Smac on apoptosis of Panc-1 cells was evaluated by flow cytometry. Results： Panc-1 was more resistant to cisplatin or 5-FU induced apoptosis than BXPC-3. Western blot revealed that chemoresistant Panc-1 highly expressed XIAP, and increased cytosolic expression of Smac might be responsible for the marked down-regulation of XIAP in chemo-sensitive BXPC-3 cells after exposure to cisplatin or 5-FU. Furthermore, cytosolic overexpression of Smac could significantly down-regulate the levels of XIAP and promote the activity of caspase-3, as well as sensitize Panc-1 cells to anticancer drug-induced apoptosis. Conclusion： Anticancer drug-induced apoptosis requires mitochondrial release of Smac and downregulation of XIAP, which may be an important determinant of chemo-sensitivity in pancreatic cancer cells. Up-regulation of cytosolic expression of Smac may act as an effective modifying signal to overcome apoptosis resistance to chemotherapy in pancreatic cancer cells.

Targeting X-linked inhibitor of apoptosis protein inhibits pancreatic cancer cell growth through p-Akt depletion

AIM: To determine whether lentivirus-mediated shRNA targeting the X-linked inhibitor of apoptosis protein (XIAP) gene could be exploited in the treatment of pancreatic cancer. METHODS: Human pancreatic cancer cells Panc-1, Mia-paca2, Bxpc-3 and SW1990, infected with lentivirus, were analyzed by real-time polymerase chain reaction (PCR). Western blotting was used to examine XIAP protein levels, survivin and p-Akt to confirm the result of real-time PCR and determine the possible mechanism. The 3-(4,5-cimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide (MTT) assay was used to measure IC50 to determine chemosensitivity to the chemotherapeutic drugs 5-fluorouracil (5-FU) and gemcitabine. A colony assay, MTT assay and a tumorigenicity experiment were used to study cell proliferation in vitro and in vivo . Caspase-3/7 activity, 4',6-diamidino-2-phenylindole-staining and flow cytometric measurements were used to study apoptosis in SW1990 cells. RESULTS: XIAP proteins were found to be differen- tially expressed among pancreatic cancer cell lines Panc-1, Mia-paca2, Bxpc-3 and SW1990. Data of real-time PCR and Western blotting showed that XIAP was reduced persistently and markedly by lentivirus-mediated shRNA. Downregulation of XIAP by transfection with XIAP shRNA resulted in decreased p-Akt expression. XIAP shRNA also inhibited the growth of pancreatic cancer cells in vitro and in vivo , enhanced drug-induced apoptosis and increased chemosensitivity to 5-FU and gemcitabine. Results also suggest that inhibition of XIAP and subsequent p-Akt depletion may have an anti-tumor effect through attenuating the ability of cancer cells to survive. CONCLUSION: Lentivirus-mediated gene therapy is an attractive strategy in the treatment of pancreatic cancer and justifies the use of lentivirus in pancreatic cancer gene therapy studies.

Baculoviral inhibitor of apoptosis protein repeatcontaining protein 3 delays early Wallerian degeneration after sciatic nerve injury

Wallerian degeneration is a complex biological process that occurs after nerve injury,and involves nerve degeneration and regeneration.Schwann cells play a crucial role in the cellular and molecular events of Wallerian degeneration of the peripheral nervous system.However,Wallerian degeneration regulating nerve injury and repair remains largely unknown,especially the early response.We have previously reported some key regulators of Wallerian degeneration after sciatic nerve injury.Baculoviral inhibitor of apoptosis protein repeat-containing protein 3(BIRC3)is an important factor that regulates apoptosis-inhibiting protein.In this study,we established rat models of right sciatic nerve injury.In vitro Schwann cell models were also established and subjected to gene transfection to inhibit and overexpress BIRC3.The data indicated that BIRC3 expression was significantly up-regulated after sciatic nerve injury.Both BIRC3 upregulation and downregulation affected the migration,proliferation and apoptosis of Schwan cells and affected the expression of related factors through activating c-fos and ERK signal pathway.Inhibition of BIRC3 delayed early Wallerian degeneration through inhibiting the apoptosis of Schwann cells after sciatic nerve injury.These findings suggest that BIRC3 plays an important role in peripheral nerve injury repair and regeneration.The study was approved by the Institutional Animal Care and Use Committee of Nantong University,China(approval No.2019-nsfc004)on March 1,2019.

ANTAGONISTIC EFFECTS OF GRANULOCYTE DERIVED INHIBITORS AND CYTOKINES ON APOPTOSIS IN POLYMORPHONUCLEAR LEUKOCYTES

An extract (G-INH) made from mature human granulocytes freshly isolated from normai blood causes human neutrophils to undergo apoptosis in vitro as shown by morphologic changes and by the typical ladder pattern of small DNA fragments noted on agarose gel electrophoresis of isolated DNA. Apoptosis occurs in from 20% to 30% of neutrophils over 24 hours of culture in vitro and the addition of G-INH to the medium causes a dose-related increase in the incidence of apoptosis. Heating G-INH at 60t for 30 minutes does not destroy its capacity to induce apoptosis but GM-CSF, G-CSF, and to a lesser extent IL-1β, antagonize this action. IL-3 does not diminish G-INH induced apoptosis of neutrophils. Substances, released from, mature neutrophils may participate in regulating the survival of other neutrophils, particularly in sites where the cells are in close proximity as in the marrow. Self destruction of post-mitotic neutrophils in marrow may thus represent an-other level at which regulation of cell production

The Apoptosis of Bovine Lens Epithelial Cells Induced by Proteasome Inhibitor MG132

To investigate the effect of proteasome inhibitor MG132 on the apoptosis of bovine lens epithelial cells （BLECs）, the cells were treated with MG132 at different concentrations for12, 24 and 36 h. The cell viability was analyzed by MTT assay and the effect of MG132 on the apoptosis of BLECs was assessed by flow cytometry （FCM）. The results showed that after treatment for the same period, the inhibitory effect of MG132 on BLECs proliferation was enhanced with the increment of the concentration of MG132 （0, 2, 5, 10, μmol/L） （P〈0.05）. The 50% inhibiting concentration （IC50） was 2.03 μmol/L when the BLECs were treated with MG132 for 36 h. MG132 also induced the apop- tosis of BLECs obviously. FCM showed that the apoptosis index of the cells treated by MG132 at 2 μmol/L for 12 h was （20.24±1.51）%, and that of the control was （0.98±0.20）% respectively （P〈0.01, n=3）. It was concluded that MG132 could lead to apoptosis of BLECs. The decrease of proteasome activity may play an important role in the formation and development of cataract.

Expression of X-linked Inhibitor of Apoptosis Protein and Its Effect on Chemotherapeutic Sensitivity of Bladder Carcinoma

The expression of X-linked inhibitor of apoptosis protein (XIAP) gene and its effect on chemotherapeutic sensitivity in bladder carcinoma was explored. By using immunohistochemistry, the expression of XIAP was detected in 47 bladder carcinomas and 5 normal bladder tissues. The XIAP gene was transfected into bladder cancer cell line T24 by liposome and the positive clone was screened by G418. Cellular XIAP mRNA level was detected by RT-PCR. Low-dose mitocycin C was administered to induce the apoptosis of T24 cells. The in vitro growth of bladder carcinoma cells was analyzed by MTT colorimetry, and the apoptosis rate was assayed by TUNEL methods. It was found XIAP was moderately expressed in bladder carcinomas with the the positive rate being 78.73% (37/47), but the positive rate was not correlated with carcinoma stages and grades (P<0.05). XIAP mRNA level in transfected T24 cells was significantly increased by 3.8 times as compared with that in the cells not transfected with XIAP. After treatment with low-dose mitomycin C (0.005 and 0.05 mg/mL), the growth rate in XIAP no-transfected control group was increased by (11.60±0.25)% and (16.51±0.87)% (P<0.05), and the apoptosis rate was decreased by (10.1±0.2)% and (11.9±0.2%) (P<0.05) respectively as compared with XIAP transfected group. It was concluded that XIAP was expressed in most of bladder carcimoma samples. Overexpression of XIAP in T24 could significantly reduce the MMC-induced apoptosis of bladder carcinoma, suggesting its effect on the chemothera- peutic sensitivity of T24 cells.

Low levels of Bax inhibitor-1 gene expression increase tunicamycin-induced apoptosis in human neuroblastoma SY5Y cells

A human SH-SY5Y neuroblastoma cell line with a low level of Bax inhibitor-1 expression was established by lentivirus-mediated RNA interference and fluorescence-activated cell sorting. In control SH-SY5Y cells, tunicamycin treatment induced endoplasmic reticulum stress-mediated apoptosis; however, after Bax inhibitor-1 gene knockdown, cell survival rates were significantly decreased and the degree of apoptosis was significantly increased following tunicamycin treatment In addition, chromatin condensation and apparent apoptotic phenomena, such as marginalization and cytoplasmic vesicles, were observed. Our findings indicate that Bax inhibitor-1 can delay apoptosis induced by endoplasmic reticulum stress.

Effect of trkA kinase inhibitor on apoptosis of human pterygium fibroblasts

Objective： The aim of this study was to investigate the growth inhibition effects and the mechanisms of trkA kinase inhibitor on human pterygium fibroblasts（HPF）. Methods： Three normal conjunctivas and eleven pterygiums were surgically collected, trkA and p75 was examined in different tissues by immunohistochemistry, trkA and p75 expression was detected in HPF by immumofluorescence method. After being treated with 10-80 nmol/L trkA kinase inhibitor for 24-96 h, the growth activities of HPF were studied by MTT colorimetry. Caspase-3 was inspected in HPF by spectrophotometric method. The apoptosis of HPF was detected by flow cytometry. Results： Expression of trkA and p75 was significantly observed in epithelium and fibroblast of pterygium tissues. Expression of trkAwas observed in epithelium and fibroblast of normal conjunc- tiva. Expression of p75 was only observed in epithelium of normal conjuncUva, trkA kinase inhibitor could effectively inhibit the growth of human pterygium fibroblasts in vitro in time and dose dependent manners. Caspase-3 expression was increased. The rates of apoptosis were 8.26%-29.62% （P 〈 0.01）. Conclusion： TrkA and p75 possibly participate in genesis and development of pterygium, trkA kinase inhibitor could induce apoptosis of human pterygium fibroblasts. Inducing apoptosis through changing the ratio of trkA and p75 in fibroblasts and up-regulate Caspase-3 was probably one of its molecular mechanisms.

Novel histone deacetylase inhibitor exhibits antitumor activity via apoptosis induction in oral squamous cell carcinoma

Epigenetic modifications such as histone deacetylation are commonly related to tumor development and histone deacetylase (HDAC) inhibitors have been shown to be potential drugs for cancer treatment. In the present study, we investigated the effects of a novel HDAC inhibitor, Ky-2, on oral squamous carcinoma cells in vitro. Cell viability was significantly reduced by treatment with Ky-2 at 25 nM, while it also led to augmentation of the proportion of cells in the sub-G1 phase and DNA fragmentation. In addition, immunoblot analysis revealed that Ky-2 enhanced the expression of apoptosis-related proteins. Our results showed that a low concentration of Ky-2 induced apoptosis in oral squamous carcinoma cells via activation of apoptotic cascades.

Discovery of a novel eEF2K inhibitor （BL-EKI03） that induces ER stress, autophagy and apoptosis in breast cancer

Aim Recent evidence has revealed that Eukaryotic elongation factor-2 kinase （eEF2K） activity may confer cancer cell adaptation to metabolic stress, and high expression of eEF2K is found in several types of cancer. Therefore, eEF2K may contribute to carcinogenesis and represent a promising therapeutic target; however, inhibi- tion of eEF2K for cancer drug discovery still remains in its infancy. This study aimed at developing a series of eEF2K inhibitor as candidate anti-tumor drugs in breast cancer and illustrating the possible mechanisms of its anti- tumor activity in vitro and in vivo. Methods In silico screening, structure modifications, MTT assay and molecular dynamics （MD） simulations were applied for the discovery of the novel eEF2K inhibitor （BL-EKI03）. Observa- tions of cell morphology were executed through several methods including ER-traeker, MDC and Hoeehst 33258 staining and GFP-LC3 transfeetion. Flow eytometrie analyses of MDC and Annexin V/PI were used for quantifica- tion of autophagy and apoptosis ratio. Western blot and ITRAQ analysis were used to explore the detailed mecha- nisms of BL-EKI03-induced ER stress, autophagie death and apoptosis in breast cancer cells. Furthermore, an in vivo xenograft mouse model was established for validating the anti-tumor efficacy of BL-EKI03. Results Firstly, a novel eEF2K inhibitor （BL-EKI03） with a good affinity for eEF2K was eventually discovered after computational screening and synthesis of a series of candidate compounds targeting eEF2K. Subsequently, our results demonstra- ted that BL-EKI03 has remarkable anti-proliferative activities and induces endoplasmie retieulum （ER） stress, au- tophagy and apoptosis in MCF-7 and MDA-MB-436 cells. More importantly, the mechanism for BL-EKI03-indueed autophagie death involves eEF2K-mediated AMPK-mTOR-ULK complex pathways. The proteomies analyses and ex-perimental validation revealed that the BL-EKI03-induced mechanism was also involved BIRC6, BNIP1, SNAP29 and Bif-1, which might be regulated by eEF2K. Moreover, BL-EKI03 exerted its anti-tumor activities without re- markable toxicity, and it also induced autophagy and apoptosis by targeting eEF2K in fifo. Conclusion In this study, a novel eEF2K inhibitor （BL-EKI03） was discovered with remarkable anti-proliferative activities and in- duced endoplasmic reticulum （ER） stress, autophagy and apoptosis of breast cancer in vitro and in fifo. These findings highlight a new small-molecule eEF2K inhibitor （BL-EKI03） that has the potential to impact future breast cancer therapy.

Effects of angiotensin converting enzyme inhibitors on cognitive function, apoptosis and oxidative stress in brain tissue of rats with cerebral infarction

Objective:To study the effects of angiotensin converting enzyme inhibitor(ACEI)on cognitive function,apoptosis and oxidative stress in brain tissue of rats with cerebral infarction.Methods:Adult male SD rats were randomly divided into control group,cerebral infarction group and ACEI group.The latter two groups were used to establish cerebral infarction model by thread embolism.The ACEI group was given oral administration of fosinopril 10mg/kg,and the other two groups were given oral administration of saline.The differences of Morris water maze cognitive function,apoptotic genes and oxidative stress indexes were compared among the three groups.Results:The escape latency of rats in cerebral infarction group was significantly longer than that in control group,the number of times of platform crossing was significantly less than that in control group,the duration of platform stay was significantly shorter than that in control group,the mRNA expression levels of Bcl-2 associated X protein(Bax),factor associated suicide(Fas),Fas ligand(FasL)and Caspase-3,the protein expression levels of phosphorylated Janus kinase(p-JAK2)and phosphorylated signal transducer and activator of transcription(p-STAT3)as well as the contents of reactive oxygen species(ROS)and malonaldehyde(MDA)in brain tissue were significantly higher than those in control group,and the mRNA expression level of B-cell lymphoma-2(Bcl-2)as well as the contents of catalase(CAT)and superoxide dismutase(SOD)in brain tissue was significantly lower than those in control group.The escape latency of rats in ACEI group was significantly shorter than that in cerebral infarction group,the number of times of platform crossing was significantly more than that in cerebral infarction group,the duration of platform stay was significantly longer than that in cerebral infarction group,the mRNA expression levels of Bax,Fas,FasL and Caspase-3,the protein expression levels of p-JAK2 and p-STAT3 as well as the contents of ROS and MDA in brain tissue were significantly lower than those in cerebral infarction group,and the mRNA expression level of Bcl-2 as well as the contents of CAT and SOD in brain tissue was significantly higher than those in cerebral infarction group.Conclusions:ACEI can improve the cognitive function of rats with cerebral infarction and inhibit the apoptosis and oxidative stress in ischemic brain tissue.

Mechanism of apoptosis induced by Mcl-1 inhibitor UMI-77 on gallbladder carcinoma GBC-SD cells

Objective:To investigate the mechanism of apoptosis induced by myeloid cell leukemia-1(Mcl-1)inhibitor UMI-77 on gallbladder carcinoma GBC-SD cells.Methods:GBC-SD cells were treated with different concentrations of UMI-77.GBC-SD cell proliferation and apoptosis were detected by MTT assay and Annexin V/PI.The expressions of Mcl-1,Bcl-2,Bcl-xL,Bax,Bak,cleaved-caspase 9,cleaved-caspase 3 and cleaved-PARP proteins in GBC-SD cells treated with UMI-77 were detected by Western blotting.Results:The results of MTT showed that different concentrations of UMI-77 had different inhibitory effects on cell proliferation of GBC-SD cells in a dose-dependent and time-dependent manner.Annexin V/PI results showed that the apoptosis rate was increasing gradually with the increase of UMI-77 concentration in a dose-dependent manner.Western blotting results showed that the expression of anti-apoptotic protein Mcl-1 was significantly decreased(p<0.05),and the expressions of Bax and Bak proteins were significantly increased respectively(p<0.05),but there were no significant changes in the expressions of Bcl-2 and Bcl-xL proteins,and the expression levels of cleaved-caspase 9,cleaved-caspase 3 and cleaved-PARP proteins were significantly increased(p<0.05)in 24 h after GBC-SD cells were treated with 10μmol/L of UMI-77.Conclusions:Mcl-1 inhibitor UMI-77 can induce the apoptosis of GBC-SD cells in a dose-dependent manner through the caspase-mediated endogenous apoptosis pathway.Therefore,Mcl-1 may become a new therapeutic target in the research on gallbladder cancer.

STAT3 as a target for inducing apoptosis in solid and hematological tumors

Studies in the past few years have provided compelling evidence for the critical role of aberrant Signal Transducer and Activator of Transcription 3 （STAT3） in malignant transformation and tumorigenesis. Thus, it is now generally accepted that STAT3 is one of the critical players in human cancer formation and represents a valid target for novel anticancer drug design. This review focuses on aberrant STAT3 and its role in promoting tumor cell survival and sup- porting the malignant phenotype. A brief evaluation of the current strategies targeting STAT3 for the development of novel anticancer agents against human tumors harboring constitutively active STAT3 will also be presented.