Displaying publications 81 - 100 of 570 in total

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  1. Mohan S, Abdelwahab SI, Kamalidehghan B, Syam S, May KS, Harmal NS, et al.
    Phytomedicine, 2012 Aug 15;19(11):1007-15.
    PMID: 22739412 DOI: 10.1016/j.phymed.2012.05.012
    The plant Artocarpus obtusus is a tropical plant that belongs to the family Moraceae. In the present study a xanthone compound Pyranocycloartobiloxanthone A (PA) was isolated from this plant and the apoptosis mechanism was investigated. PA induced cytotoxicity was observed using MTT assay. High content screening (HCS) was used to observe the nuclear condensation, cell permeability, mitochondrial membrane potential (MMP) and cytochrome c release. Reactive oxygen species formation was investigated on treated cells by using fluorescent analysis. Human apoptosis proteome profiler assays were performed to investigate the mechanism of cell death. In addition mRNA levels of Bax and Bcl2 were also checked using RT-PCR. Caspase 3/7, 8 and 9 were measured for their induction while treatment. The involvement of NF-κB was analyzed using HCS assay. The results showed that PA possesses the characteristics of selectively inducing cell death of tumor cells as no inhibition was observed in non-tumorigenic cells even at 30 μg/ml. Treatment of MCF7 cells with PA induced apoptosis with cell death-transducing signals, that regulate the MMP by down-regulation of Bcl2 and up-regulation of Bax, triggering the cytochrome c release from mitochondria to cytosol. The release of cytochrome c triggered the activation of caspases-9, then activates downstream executioner caspase-3/7 and consequently cleaved specific substrates leading to apoptotic changes. This form of apoptosis was found closely associated with the extrinsic pathway caspase (caspase-8) and inhibition of translocation of NF-κB from cytoplasm to nucleus. The results demonstrated that PA induced apoptosis of MCF7 cells through NF-κB and Bcl2/Bax signaling pathways with the involvement of caspases.
    Matched MeSH terms: Apoptosis/drug effects*
  2. Awang N, Kamaludin NF, Hamid A, Mokhtar NW, Rajab NF
    Pak J Biol Sci, 2012 Sep 01;15(17):833-8.
    PMID: 24163967
    Studies on the discovery of new cancer treatment by using metal-based compounds such as tin (Sn) has now greatly being synthesized and evaluated to identify their effectiveness and suitability to be developed as a new anticancer drug.

    APPROACH: This study was carried out to evaluate the cytotoxicity of triphenyltin(lV) methylisopropyldithiocarbamate (compound 1) and triphenyltin(IV) ethylisopropyldithiocarbamate (compound (2) on chronic myelogenus leukemia cells. The determination of their cytotoxicity (IC50) at different time of exposure and concentration was carried out through the employment of 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT) assay.

    RESULTS: The IC50 values obtained for compound 1 and 2 following treatment at 24, 48 and 72 h were 0.660, 0.223, 0.370 microM and 0.677, 0.306, 0.360 microM, respectively. Cell morphological changes such as apoptotic and necrotic features were also been observed.

    CONCLUSION: The compounds tested were found to give cytotoxic effect against chronic myelogenus leukemia (K-562) cell at a micromolar dose. Thus, further study on their specific mechanism of actions in the human cells should be carried out to elucidate their potential as an anticancer agent.

    Matched MeSH terms: Apoptosis/drug effects
  3. Oskoueian E, Abdullah N, Ahmad S
    Molecules, 2012 Sep 10;17(9):10816-30.
    PMID: 22964499 DOI: 10.3390/molecules170910816
    Jatropha meal produced from the kernel of Jatropha curcas Linn. grown in Malaysia contains phorbol esters (PEs). The potential benefits of PEs present in the meal as anticancer agent are still not well understood. Hence, this study was conducted to evaluate the cytotoxic effects and mode of actions of PEs isolated from Jatropha meal against breast (MCF-7) and cervical (HeLa) cancer cell lines. Isolated PEs inhibited cells proliferation in a dose-dependent manner of both MCF-7 and HeLa cell lines with the IC₅₀ of 128.6 ± 2.51 and 133.0 ± 1.96 µg PMA equivalents/mL respectively, while the values for the phorbol 12-myristate 13-acetate (PMA) as positive control were 114.7 ± 1.73 and 119.6 ± 3.73 µg/mL, respectively. Microscopic examination showed significant morphological changes that resemble apoptosis in both cell lines when treated with PEs and PMA at IC₅₀ concentration after 24 h. Flow cytometry analysis and DNA fragmentation results confirmed the apoptosis induction of PEs and PMA in both cell lines. The PEs isolated from Jatropha meal activated the PKC-δ and down-regulated the proto-oncogenes (c-Myc, c-Fos and c-Jun). These changes probably led to the activation of Caspase-3 protein and apoptosis cell death occurred in MCF-7 and HeLa cell lines upon 24 h treatment with PEs and PMA. Phorbol esters of Jatropha meal were found to be promising as an alternative to replace the chemotherapeutic drugs for cancer therapy.
    Matched MeSH terms: Apoptosis/drug effects*
  4. Siew EL, Chan KM, Williams GT, Ross D, Inayat-Hussain SH
    Free Radic. Biol. Med., 2012 Oct 15;53(8):1616-24.
    PMID: 22687461 DOI: 10.1016/j.freeradbiomed.2012.05.046
    The Fau gene (Finkel-Biskis-Reilly murine sarcoma virus (FBR-MuSV)-associated ubiquitously expressed gene) was identified as a potential tumor suppressor gene using a forward genetics approach. Downregulation of Fau by overexpression of its reverse sequence has been shown to inhibit apoptosis induced by DNA-damaging agents. To address a potential role of Fau in benzene toxicity, we investigated the apoptotic effects of hydroquinone (HQ), a major benzene metabolite, in W7.2 mouse thymoma cells transfected with either a plasmid construct expressing the antisense sequence of Fau (rfau) or the empty vector (pcDNA3.1) as a control. HQ induced apoptosis via increased production of reactive oxygen species and DNA damage, measured using dihydroethidine (HE) staining and alkaline Comet assay, respectively, in W7.2 pcDNA3.1 cells. In contrast, when Fau was downregulated by the antisense sequence in W7.2 rfau cells, HQ treatment did not cause DNA damage and oxidative stress and these cells were markedly more resistant to HQ-induced apoptosis. Further investigation revealed that there was an upregulation of NAD(P)H: quinone oxidoreductase 1 (NQO1), a detoxification enzyme for benzene-derived quinones, in W7.2 rfau cells. Compromising cellular NQO1 by use of a specific mechanism-based inhibitor (MAC 220) and NQO1 siRNA resensitized W7.2 rfau cells to HQ-induced apoptosis. Silencing of Fau in W7.2 wild-type cells resulted in increased levels of NQO1, confirming that downregulation of Fau results in NQO1 upregulation which protects against HQ-induced apoptosis.
    Matched MeSH terms: Apoptosis/drug effects*
  5. Ho KL, Chong PP, Yazan LS, Ismail M
    J Med Food, 2012 Dec;15(12):1096-102.
    PMID: 23216109 DOI: 10.1089/jmf.2012.2245
    Vanillin is the substance responsible for the flavor and smell of vanilla, a widely used flavoring agent. Previous studies reported that vanillin is a good antimutagen and anticarcinogen. However, there are also some contradicting findings showing that vanillin was a comutagen and cocarcinogen. This study investigated whether vanillin is an anticarcinogen or a cocarcinogen in rats induced with azoxymethane (AOM). Rats induced with AOM will develop aberrant crypt foci (ACF). AOM-challenged rats were treated with vanillin orally and intraperitoneally at low and high concentrations and ACF density, multiplicity, and distribution were observed. The gene expression of 14 colorectal cancer-related genes was also studied. Results showed that vanillin consumed orally had no effect on ACF. However, high concentrations (300 mg/kg body weight) of vanillin administered through intraperitoneal injection could increase ACF density and ACF multiplicity. ACF were mainly found in the distal colon rather than in the mid-section and proximal colon. The expression of colorectal cancer biomarkers, protooncogenes, recombinational repair, mismatch repair, and cell cycle arrest, and tumor suppressor gene expression were also affected by vanillin. Vanillin was not cocarcinogenic when consumed orally. However, it was cocarcinogenic when being administered intraperitoneally at high concentration. Hence, the use of vanillin in food should be safe but might have cocarcinogenic potential when it is used in high concentration for therapeutic purposes.
    Matched MeSH terms: Apoptosis/drug effects
  6. Dhurga DB, Suresh KG, Tan TC, Chandramathi S
    Trans R Soc Trop Med Hyg, 2012 Dec;106(12):725-30.
    PMID: 23141370 DOI: 10.1016/j.trstmh.2012.08.005
    Previous studies have shown that apoptosis-like features are observed in Blastocystis spp., an intestinal protozoan parasite, when exposed to the cytotoxic drug metronidazole (MTZ). This study reports that among the four subtypes of Blastocystis spp. investigated for rate of apoptosis when treated with MTZ, subtype 3 showed the highest significant increase after 72h of in vitro culture when treated with MTZ at 0.1mg/ml (79%; p<0.01) and 0.0001mg/ml (89%; p<0.001). The close correlation between viable cells and apoptotic cells for both dosages implies that the pathogenic potential of these isolates has been enhanced when treated with MTZ. This suggests that there is a mechanism in Blastocystis spp. that actually regulates the apoptotic process to produce higher number of viable cells when treated. Apoptosis may not just be programmed cell death but instead a mechanism to increase the number of viable cells to ensure survival during stressed conditions. The findings of the present study have an important contribution to influence chemotherapeutic approaches when developing drugs against the emerging Blastocystis spp. infections.
    Matched MeSH terms: Apoptosis/drug effects*
  7. Aisha AF, Abu-Salah KM, Ismail Z, Majid AM
    PMID: 22818000
    BACKGROUND: Xanthones are a group of oxygen-containing heterocyclic compounds with remarkable pharmacological effects such as anti-cancer, antioxidant, anti-inflammatory, and antimicrobial activities.
    METHODS: A xanthones extract (81% α-mangostin and 16% γ-mangostin), was prepared by crystallization of a toluene extract of G. mangostana fruit rinds and was analyzed by LC-MS. Anti-colon cancer effect was investigated on HCT 116 human colorectal carcinoma cells including cytotoxicity, apoptosis, anti-tumorigenicity, and effect on cell signalling pathways. The in vivo anti-colon cancer activity was also investigated on subcutaneous tumors established in nude mice.
    RESULTS: The extract showed potent cytotoxicity (median inhibitory concentration 6.5 ± 1.0 μg/ml), due to induction of the mitochondrial pathway of apoptosis. Three key steps in tumor metastasis including the cell migration, cell invasion and clonogenicity, were also inhibited. The extract and α-mangostin up-regulate the MAPK/ERK, c-Myc/Max, and p53 cell signalling pathways. The xanthones extract, when fed to nude mice, caused significant growth inhibition of the subcutaneous tumor of HCT 116 colorectal carcinoma cells.
    CONCLUSIONS: Our data suggest new mechanisms of action of α-mangostin and the G. mangostana xanthones, and suggest the xanthones extract of as a potential anti-colon cancer candidate.
    Matched MeSH terms: Apoptosis/drug effects
  8. In LL, Arshad NM, Ibrahim H, Azmi MN, Awang K, Nagoor NH
    PMID: 23043547 DOI: 10.1186/1472-6882-12-179
    Oral cancers although preventable, possess a low five-year survival rate which has remained unchanged over the past three decades. In an attempt to find a more safe, affordable and effective treatment option, we describe here the use of 1'S-1'-acetoxychavicol acetate (ACA), a component of Malaysian ginger traditionally used for various medicinal purposes.
    Matched MeSH terms: Apoptosis/drug effects
  9. Ismail N, Ismail M, Fathy SF, Musa SN, Imam MU, Foo JB, et al.
    Int J Mol Sci, 2012;13(8):9692-708.
    PMID: 22949825 DOI: 10.3390/ijms13089692
    The neuroprotective and antioxidative effects of germinated brown rice (GBR), brown rice (BR) and commercially available γ-aminobutyric acid (GABA) against cell death induced by hydrogen peroxide (H(2)O(2)) in human neuroblastoma SH-SY5Y cells have been investigated. Results show that GBR suppressed H(2)O(2)-mediated cytotoxicity and induced G0/G1 phase cell cycle arrest in SH-SY5Y cells. Moreover, GBR reduced mitochondrial membrane potential (MMP) and prevented phosphatidylserine (PS) translocation in SH-SY5Y cells, key features of apoptosis, and subsequent cell death. GBR exhibited better neuroprotective and antioxidative activities as compared to BR and GABA. These results indicate that GBR possesses high antioxidative activities and suppressed cell death in SH-SY5Y cells by blocking the cell cycle re-entry and apoptotic mechanisms. Therefore, GBR could be developed as a value added functional food to prevent neurodegenerative diseases caused by oxidative stress and apoptosis.
    Matched MeSH terms: Apoptosis/drug effects*
  10. Chong HZ, Yeap SK, Rahmat A, Akim AM, Alitheen NB, Othman F, et al.
    PMID: 22909149 DOI: 10.1186/1472-6882-12-134
    Our previous study had shown that P. amaryllifolius was able to selectively inhibit cell proliferation of hormone independent breast cancer cell line MDA-MB-231. To understand the mode of killing and mechanism of action for P. amaryllifolius, the ethanol extract was evaluated for their alteration of cell cycle progression, PS externalization, DNA fragmentation and expression of anti/pro-apoptotic related protein.
    Matched MeSH terms: Apoptosis/drug effects*
  11. Wen CT, Hussein SZ, Abdullah S, Karim NA, Makpol S, Mohd Yusof YA
    Asian Pac J Cancer Prev, 2012;13(4):1605-10.
    PMID: 22799375
    Gelam and Nenas monofloral honeys were investigated in this study for their chemopreventive effects against HT 29 colon cancer cells. MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H- tetrazolim) assays showed more effective inhibition of colon cancer cells proliferation by Gelam honey with IC₅₀ values of 39.0 mg/ml and 85.5 mg/ml respectively after 24 hours of treatment. Alkali comet assays revealed both honeys increased DNA damage significantly in a dose dependent manner. In addition, annexin V-FITC/PI flow cytometry demonstrated that at IC₅₀ concentrations and above, both Gelam and Nenas honeys induced apoptosis significantlyat values higher than for necrosis (p<0.05). Measurement of prostaglandin E₂ (PGE₂) confirmed that Gelam and Nenas honeys reduced its production in H₂O₂ inflammation-induced colon cancer cells. In conclusion, our study indicated and confirmed that both Gelam and Nenas honeys are capable of suppressing the growth of HT 29 colon cancer cells by inducing apoptosis and suppressing inflammation.
    Matched MeSH terms: Apoptosis/drug effects
  12. Ramasamy S, Abdul Wahab N, Zainal Abidin N, Manickam S, Zakaria Z
    PLoS One, 2012;7(4):e34793.
    PMID: 22536331 DOI: 10.1371/journal.pone.0034793
    Phyllanthus watsonii Airy Shaw is an endemic plant found in Peninsular Malaysia. Although there are numerous reports on the anti cancer properties of other Phyllanthus species, published information on the cytotoxicity of P. watsonii are very limited. The present study was carried out with bioassay-guided fractionation approach to evaluate the cytotoxicity and apoptosis induction capability of the P. watsonii extracts and fractions on human gynecologic (SKOV-3 and Ca Ski) and colon (HT-29) cancer cells. P. watsonii extracts exhibited strong cytotoxicity on all the cancer cells studied with IC(50) values of ≤ 20.0 µg/mL. Hexane extract of P. watsonii was further subjected to bioassay-guided fractionation and yielded 10 fractions (PW-1→PW-10). PW-4→PW-8 portrayed stronger cytotoxic activity and was further subjected to bioassay-guided fractionation and resulted with 8 sub-fractions (PPWH-1→PPWH-8). PPWH-7 possessed greatest cytotoxicity (IC(50) values ranged from 0.66-0.83 µg/mL) and was selective on the cancer cells studied. LC-MS/MS analysis of PPWH-7 revealed the presence of ellagic acid, geranic acid, glochidone, betulin, phyllanthin and sterol glucoside. Marked morphological changes, ladder-like appearance of DNA and increment in caspase-3 activity indicating apoptosis were clearly observed in both human gynecologic and colon cancer cells treated with P. watsonii especially with PPWH-7. The study also indicated that P. watsonii extracts arrested cell cycle at different growth phases in SKOV-3, Ca Ski and HT-29 cells. Cytotoxic and apoptotic potential of the endemic P. watsonii was investigated for the first time by bioassay-guided approach. These results demonstrated that P. watsonii selectively inhibits the growth of SKOV-3, Ca Ski and HT-29 cells through apoptosis induction and cell cycle modulation. Hence, P. watsonii has the potential to be further exploited for the discovery and development of new anti cancer drugs.
    Matched MeSH terms: Apoptosis/drug effects*
  13. Makpol S, Abdul Rahim N, Hui CK, Ngah WZ
    Oxid Med Cell Longev, 2012;2012:785743.
    PMID: 22919441 DOI: 10.1155/2012/785743
    In this study, we determined the molecular mechanism of γ-tocotrienol (GTT) in preventing cellular aging by focusing on its anti-apoptotic effect in stress-induced premature senescence (SIPS) model of human diploid fibroblasts (HDFs). Results obtained showed that SIPS exhibited senescent-phenotypic characteristic, increased expression of senescence-associated β-galactosidase (SA β-gal) and promoted G(0)/G(1) cell cycle arrest accompanied by shortening of telomere length with decreased telomerase activity. Both SIPS and senescent HDFs shared similar apoptotic changes such as increased Annexin V-FITC positive cells, increased cytochrome c release and increased activation of caspase-9 and caspase-3 (P < 0.05). GTT treatment resulted in a significant reduction of Annexin V-FITC positive cells, inhibited cytochrome c release and decreased activation of caspase-9 and caspase-3 (P < 0.05). Gene expression analysis showed that GTT treatment down regulated BAX mRNA, up-regulated BCL2A1 mRNA and decreased the ratio of Bax/Bcl-2 protein expression (P < 0.05) in SIPS. These findings suggested that GTT inhibits apoptosis by modulating the upstream apoptosis cascade, causing the inhibition of cytochrome c release from the mitochondria with concomitant suppression of caspase-9 and caspase-3 activation. In conclusion, GTT delays cellular senescence of human diploid fibroblasts through the inhibition of intrinsic mitochondria-mediated pathway which involved the regulation of pro- and anti-apoptotic genes and proteins.
    Matched MeSH terms: Apoptosis/drug effects*
  14. Aisha AF, Abu-Salah KM, Ismail Z, Majid AM
    Molecules, 2012;17(3):2939-54.
    PMID: 22402764 DOI: 10.3390/molecules17032939
    Despite the progress in colon cancer treatment, relapse is still a major obstacle. Hence, new drugs or drug combinations are required in the battle against colon cancer. α-Mangostin and betulinic acid (BA) are cytotoxic compounds that work by inducing the mitochondrial apoptosis pathway, and cisplatin is one of the most potent broad spectrum anti-tumor agents. This study aims to investigate the enhancement of BA cytotoxicity by α-mangostin, and the cytoprotection effect of α-mangostin and BA on cisplatin-induced cytotoxicity on HCT 116 human colorectal carcinoma cells. Cytotoxicity was investigated by the XTT cell proliferation test, and the apoptotic effects were investigated on early and late markers including caspases-3/7, mitochondrial membrane potential, cytoplasmic shrinkage, and chromatin condensation. The effect of α-mangostin on four signalling pathways was also investigated by the luciferase assay. α-Mangostin and BA were more cytotoxic to the colon cancer cells than to the normal colonic cells, and both compounds showed a cytoprotective effect against cisplatin-induced cytotoxicity. On the other hand, α-mangostin enhanced the cytotoxic and apoptotic effects of BA. Combination therapy hits multiple targets, which may improve the overall response to the treatment, and may reduce the likelihood of developing drug resistance by the tumor cells. Therefore, α-mangostin and BA may provide a novel combination for the treatment of colorectal carcinoma. The cytoprotective effect of the compounds against cisplatin-induced cytotoxicity may find applications as chemopreventive agents against carcinogens, irradiation and oxidative stress, or to neutralize cisplatin side effects.
    Matched MeSH terms: Apoptosis/drug effects
  15. Alabsi AM, Ali R, Ali AM, Al-Dubai SA, Harun H, Abu Kasim NH, et al.
    Asian Pac J Cancer Prev, 2012;13(10):5131-6.
    PMID: 23244123
    Cancer is one of the major health problems worldwide and its current treatments have a number of undesired adverse side effects. Natural compounds may reduce these. Currently, a few plant products are being used to treat cancer. In this study, goniothalamin, a natural occurring styryl-lactone extracted from Goniothalamus macrophyllus, was investigated for cytotoxic properties against cervical cancer (HeLa), breast carcinoma (MCF-7) and colon cancer (HT29) cells as well as normal mouse fibroblast (3T3) using MTT assay. Fluorescence microscopy showed that GTN is able to induce apoptosis in HeLa cells in a time dependent manner. Flow cytometry further revealed HeLa cells treated with GTN to be arrested in the S phase. Phosphatidyl serine properties present during apoptosis enable early detection of the apoptosis in the cells. Using annexin V/PI double staining it could be shown that GTN induces early apoptosis on HeLa cells after 24, 48 and 72 h. It could be concluded that goniothalamin showing a promising cytotoxicity effect against several cancer cell lines including cervical cancer cells (HeLa) with apoptosis as the mode of cell death induced on HeLa cells by Goniothalamin was.
    Matched MeSH terms: Apoptosis/drug effects*
  16. Oskoueian E, Abdullah N, Ahmad S
    Int J Mol Sci, 2012;13(11):13816-29.
    PMID: 23203036 DOI: 10.3390/ijms131113816
    The direct feeding of Jatropha meal containing phorbol esters (PEs) indicated mild to severe toxicity symptoms in various organs of different animals. However, limited information is available on cellular and molecular mechanism of toxicity caused by PEs present in Jatropha meal. Thus, the present study was conducted to determine the cytotoxic and mode of action of PEs isolated from Jatropha meal using human hepatocyte (Chang) and African green monkey kidney (Vero) cell lines. The results showed that isolated PEs inhibited cell proliferation in a dose-dependent manner in both cell lines with the CC(50) of 125.9 and 110.3 μg/mL, respectively. These values were compatible to that of phorbol 12-myristate 13-acetate (PMA) values as positive control i.e., 124.5 and 106.3 μg/mL respectively. Microscopic examination, flow cytometry and DNA fragmentation results confirmed cell death due to apoptosis upon treatment with PEs and PMA at CC(50) concentration for 24 h in both cell lines. The Western blot analysis revealed the overexpression of PKC-δ and activation of caspase-3 proteins which could be involved in the mechanism of action of PEs and PMA. Consequently, the PEs isolated form Jatropha meal caused toxicity and induced apoptosis-mediated proliferation inhibition toward Chang and Vero cell lines involving over-expression of PKC-δ and caspase-3 as their mode of actions.
    Matched MeSH terms: Apoptosis/drug effects*
  17. Abubakar MB, Abdullah WZ, Sulaiman SA, Suen AB
    Int J Mol Sci, 2012;13(11):15054-73.
    PMID: 23203111 DOI: 10.3390/ijms131115054
    Hematologic malignancies constitute about 9% of all new cases of cancers as reported via the GLOBOCAN series by International Agency for Research on Cancer (IARC) in 2008. So far, the conventional therapeutic and surgical approaches to cancer therapy have not been able to curtail the rising incidence of cancers, including hematological malignancies, worldwide. The last decade has witnessed great research interest in biological activities of phenolic compounds that include anticancer, anti-oxidation and anti-inflammation, among other things. A large number of anticancer agents combat cancer through cell cycle arrest, induction of apoptosis and differentiation, as well as through inhibition of cell growth and proliferation, or a combination of two or more of these mechanisms. Various phenolic compounds from different sources have been reported to be promising anticancer agents by acting through one of these mechanisms. Honey, which has a long history of human consumption both for medicinal and nutritional uses, contains a variety of phenolic compounds such as flavonoids, phenolic acids, coumarins and tannins. This paper presents a review on the molecular mechanisms of the anti-leukemic activity of various phenolic compounds on cell cycle, cell growth and proliferation and apoptosis, and it advocates that more studies should be conducted to determine the potential role of honey in both chemoprevention and chemotherapy in leukemia.
    Matched MeSH terms: Apoptosis/drug effects
  18. Chan KK, Wong RS, Mohamed SM, Ibrahim TA, Abdullah M, Nadarajah VD
    PMID: 22591286
    Bacillus thuringiensis (Bt) parasporal proteins with selective anticancer activity have recently garnered interest. This study determines the efficacy and mode of cell death of Bt 18 parasporal proteins against 3 leukemic cell lines (CEM-SS, CCRF-SB and CCRF-HSB-2).Cell-based biochemical analysis aimed to determine cell viability and the percentage of apoptotic cell death in treated cell lines; ultrastructural analysis to study apoptotic changes and Western blot to identify the parasporal proteins' binding site were performed. Bt 18 parasporal proteins moderately decreased viability of leukemic cells but not that of normal human T lymphocytes. Further purification of the proteins showed changes in inhibition selectivity. Phosphatidylserine externalization, active caspase-3, cell cycle, and ultrastructural analysis confirmed apoptotic activity and S-phase cell-cycle arrest. Western blot analysis demonstrated glyceraldehyde 3-phosphate dehydrogenase as a binding protein. We suggest that Bt 18 parasporal proteins inhibit leukemic cell viability by cell-cycle arrest and apoptosis and that glyceraldehyde 3-phosphate dehydrogenase binding initiates apoptosis.
    Matched MeSH terms: Apoptosis/drug effects*
  19. Arbab IA, Abdul AB, Sukari MA, Abdullah R, Syam S, Kamalidehghan B, et al.
    J Ethnopharmacol, 2013 Jan 9;145(1):343-54.
    PMID: 23178663 DOI: 10.1016/j.jep.2012.11.020
    Clausena excavata Burm. f. has been used in folk medicines in eastern Thailand for the treatment of cancer.
    Matched MeSH terms: Apoptosis/drug effects*
  20. Ramasamy S, Abdul Wahab N, Zainal Abidin N, Manickam S
    Exp. Toxicol. Pathol., 2013 Mar;65(3):341-9.
    PMID: 22217449 DOI: 10.1016/j.etp.2011.11.005
    Species of Phyllanthus have traditionally been used for hundreds of years for treating many ailments including diabetes, anemia, bronchitis and hepatitis. The present study aims to investigate the cytotoxic and apoptotic effects of methanol (PWM), hexane (PWH) and ethyl acetate (PWE) extracts from the leaves of the endemic plant Phyllanthus watsonii Airy Shaw (Phyllanthaceae) on MCF-7 human breast cancer cells. We observed that the PWM, PWH and PWE extracts were cytotoxic and selectively inhibited the growth and proliferation of MCF-7 cells compared to untreated control in a dose dependent manner with an IC(50) of 12.7 ± 4.65, 7.9 ± 0.60 and 7.7 ± 0.29 μg/ml, respectively. However, the extracts were not toxic at these concentrations to normal human lung fibroblast MRC-5 cells. Cell death induced by PWM, PWH and PWE extracts were mainly due to apoptosis which was characterized by apoptotic morphological changes and a nuclear DNA fragmentation. Caspase-3 activation following P. watsonii extracts treatment was also evident for apoptotic cell death which was preceded by an S phase cell cycle perturbation. The results suggested that the cytotoxic activity of P. watsonii extracts was related to an early event of cell cycle perturbation and a later event of apoptosis. Hence, P. watsonii displays potential to be further exploited in the discovery and development of new anticancer agents.
    Matched MeSH terms: Apoptosis/drug effects*
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