Displaying publications 61 - 80 of 112 in total

Abstract:
Sort:
  1. Benchoula K, Parhar IS, Wong EH
    Arch Biochem Biophys, 2021 Feb 15;698:108743.
    PMID: 33382998 DOI: 10.1016/j.abb.2020.108743
    Hyperglycaemia causes pancreatic β-cells to release insulin that then attaches to a specific expression of receptor isoform and reverses high glucose concentrations. It is well known that insulin is capable of initiating insulin-receptor substrate (IRS)/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB) signaling pathways in target cells; such as liver, adipose tissues, and muscles. However, recent discoveries indicate that many other pathways, such as the Hedgehog (Hh) and growth factor-stimulating Wingless-related integration (Wnt) signaling pathways; are activated in hyperglycaemia as well. Although these two pathways are traditionally thought to have a decisive role in cellular growth and differentiation only, recent reports show that they are involved in regulating cellular homeostasis and energy balance. While insulin-activated IRS/PI3K/PKB pathway cascades are primarily known to reduce glucose production, it was recently discovered to increase the Hh signaling pathway's stability, thereby activating the PI3K/PKB/mammalian target of rapamycin complex 2 (mTORC2) signaling pathway. The Hh signaling pathway not only plays a role in lipid metabolism, insulin sensitivity, inflammatory response, diabetes-related complications, but crosstalks with the Wnt signaling pathway resulting in improved insulin sensitivity and decrease inflammatory response in diabetes.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  2. Bakhtiar A, Chowdhury EH
    Asian J Pharm Sci, 2021 Mar;16(2):236-252.
    PMID: 33995617 DOI: 10.1016/j.ajps.2020.11.002
    Genetic intervention via the delivery of functional genes such as plasmid DNA (pDNA) and short-interfering RNA (siRNA) offers a great way to treat many single or multiple genetic defects effectively, including mammary carcinoma. Delivery of naked therapeutic genes or siRNAs is, however, short-lived due to biological clearance by scavenging nucleases and circulating monocytes. Low cellular internalization of negatively-charged nucleic acids further causes low transfection or silencing activity. Development of safe and effectual gene vectors is therefore undeniably crucial to the success of nucleic acid delivery. Inorganic nanoparticles have attracted considerable attention in the recent years due to their high loading capacity and encapsulation activity. Here we introduce strontium salt-based nanoparticles, namely, strontium sulfate, strontium sulfite and strontium fluoride as new inorganic nanocarriers. Generated strontium salt particles were found to be nanosized with high affinity towards negatively-charged pDNA and siRNA. Degradation of the particles was seen with a drop in pH, suggesting their capacity to respond to pH change and undergo dissolution at endosomal pH to release the genetic materials. While the particles are relatively nontoxic towards the cells, siRNA-loaded SrF2 and SrSO3 particles exerted superior transgene expression and knockdown activity of MAPK and AKT, leading to inhibition of their phosphorylation to a distinctive extent in both MCF-7 and 4T1 cells. Strontium salt nanoparticles have thus emerged as a promising tool for applications in cancer gene therapy.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  3. Baharudin R, Ab Mutalib NS, Othman SN, Sagap I, Rose IM, Mohd Mokhtar N, et al.
    Front Pharmacol, 2017;8:47.
    PMID: 28243201 DOI: 10.3389/fphar.2017.00047
    Resistance to 5-Fluorouracil (5-FU) is a major obstacle to the successful treatment of colorectal cancer (CRC) and posed an increased risk of recurrence. DNA methylation has been suggested as one of the underlying mechanisms for recurrent disease and its contribution to the development of drug resistance remains to be clarified. This study aimed to determine the methylation phenotype in CRC for identification of predictive markers for chemotherapy response. We performed DNA methylation profiling on 43 non-recurrent and five recurrent CRC patients using the Illumina Infinium HumanMethylation450 Beadchip assay. In addition, CRC cells with different genetic backgrounds, response to 5-FU and global methylation levels (HT29 and SW48) were treated with 5-FU and DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-azadC). The singular and combined effects of these two drug classes on cell viability and global methylation profiles were investigated. Our genome-wide methylation study on the clinical specimens showed that recurrent CRCs exhibited higher methylation levels compared to non-recurrent CRCs. We identified 4787 significantly differentially methylated genes (P < 0.05); 3112 genes were hyper- while 1675 genes were hypomethylated in the recurrent group compared to the non-recurrent. Fifty eight and 47 of the significantly hypermethylated and hypomethylated genes have an absolute recurrent/non-recurrent methylation difference of ≥20%. Most of the hypermethylated genes were involved in the MAPK signaling pathway which is a key regulator for apoptosis while the hypomethylated genes were involved in the PI3K-AKT signaling pathway and proliferation process. We also demonstrate that 5-azadC treatment enhanced response to 5-FU which resulted in significant growth inhibition compared to 5-FU alone in hypermethylated cell lines SW48. In conclusion, we found the evidence of five potentially biologically important genes in recurrent CRCs that could possibly serve as a new potential therapeutic targets for patients with chemoresistance. We postulate that aberrant methylation of CCNEI, CCNDBP1, PON3, DDX43, and CHL1 in CRC might be associated with the recurrence of CRC and 5-azadC-mediated restoration of 5-FU sensitivity is mediated at least in part by MAPK signaling pathway.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  4. Yuhaniza Shafinie Kamsani, Mohd Hamim Rajikin
    MyJurnal
    This review summarizes the impact of tocotrienols (TCTs) as antioxidants in minimizing oxidative stress (OS), particularly in embryos exposed to OS causing agents. OS level is increased, for example, by nicotine, a major alkaloid content in cigarette, which is also a source of exogenous reactive oxygen species (ROS). Increased nicotine-induced OS increases cell stress response, which is a common trigger leading to embryonic cell death. Having more profound anti-oxidative stress effects than its counterpart tocopherol, TCTs improve blastocyst implantation, foetal growth, pregnancy outcome and survival of the neonates affected by nicotine. In reversing cell developmental arrest caused by nicotine-induced OS, TCTs enhances PDK-1 expression in the P13K/Akt pathway and permit embryonic development beyond the 4-cell stage with the production of more morulae. At the cytoskeletal level, TCTs increase the number of nicotine-induced apoptotic cells, through caspase 8 activation in the mitochondria. TCTs facilitate rough endoplasmic reticulum (rER) stress-mediated apoptosis and autophagy, resulting from nicotine-induced OS. Reduced vesicular population in TCT supplemented oocytes on the other hand may suggest reduced secretion of apoptotic cell bodies thus probably minimizing vesicular apoptosis during oocyte maturation. Further extensive research is required to develop TCTs as a tool in specific therapeutic approaches to overcome the detrimental effects of OS.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  5. Yap HM, Israf DA, Harith HH, Tham CL, Sulaiman MR
    Front Pharmacol, 2019;10:1148.
    PMID: 31649532 DOI: 10.3389/fphar.2019.01148
    Increased ASM mass, primarily due to ASM hyperplasia, has been recognized as a hallmark of airway remodeling in asthma. Increased ASM mass is the major contributor to the airway narrowing, thus worsening the bronchoconstriction in response to stimuli. Inflammatory mediators and growth factors released during inflammation induce increased ASM mass surrounding airway wall via increased ASM proliferation, diminished ASM apoptosis and increased ASM migration. Several major pathways, such as MAPKs, PI3K/AKT, JAK2/STAT3 and Rho kinase, have been reported to regulate these cellular activities in ASM and were reported to be interrelated at certain points. This article aims to provide an overview of the signaling pathways/molecules involved in ASM hyperplasia as well as the mapping of the interplay/crosstalk between these major pathways in mediating ASM hyperplasia. A more comprehensive understanding of the complexity of cellular signaling in ASM cells will enable more specific and safer drug development in the control of asthma.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  6. Yap Wei Boon, Shaktypreya Nadarajah, Nadiah Shidik, Noorjahan Banu Mohammed Alitheen
    Jurnal Sains Kesihatan Malaysia, 2018;16(101):15-22.
    MyJurnal
    Breast cancer is one of the commonest cancers among women. Conventional therapies cause adverse side effects in patients. Cytokine immunotherapy such as interleukin-27 (IL-27) has been sought as an alternative cancer treatment in recent years. IL-27 has been shown to improve anticancer immunity and anti-angiogenesis in cancers, however, its effect on apoptotic and anti-apoptotic gene expression especially in breast cancers is yet to be explored. Cytotoxicity of IL-27 in non-cancerous (184b5) and cancerous (MCF-7 and MDA-MB-231) breast cell lines was first determined for 24-72 h in this study. The results indicated that IL-27 treatment did not retard 184b5 cell growth, however, did inhibit MCF-7 (48 h) and MDA-MB-231 (72 h) cell growth with IC50 at 442 and 457 ng/ml, respectively. Apoptotic (TRAIL, FADD, FAS, caspase-3 and caspase-8) and anti-apoptotic (BCL-2, AKT, and COX-2) genes were then amplified from untreated (control) and treated breast cancer cells and studied. TRAIL, caspase-3, caspase-8 gene expression was significantly (p < 0.05) upregulated in treated MCF-7 (442 ng/ml) and MDA-MB-231 (457 ng/ml) cells. Expression of FADD and FAS genes was not detected in both control and treated MCF-7 and MDA-MB-231 cells. COX-2 gene was also not expressed by MCF-7 cells, but reduced significantly (p < 0.05) in treated MDA-MB-231 cells. In MDA-MB-231 cells, IL-27 treatment seemed to slightly enhance the expression of AKT and BCL-2 genes which, on the other hand, was downregulated in treated MCF-7 cells. Conclusively, IL-27 is able to inhibit breast cancer cell growth and regulate apoptotic and anti-apoptotic gene expression in breast cancer cells.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  7. Wong SK, Chin KY, Ima-Nirwana S
    Front Pharmacol, 2020;11:430.
    PMID: 32317977 DOI: 10.3389/fphar.2020.00430
    Lithium, the lightest natural-occurring alkali metal with an atomic number of three, stabilizes the mood to prevent episodes of acute manic and depression. Multiple lines of evidence point to lithium as an anti-suicidal, anti-viral, anti-cancer, immunomodulatory, neuroprotective and osteoprotective agent. This review article provides a comprehensive review of studies investigating the bone-enhancing effects of lithium and its possible underlying molecular mechanisms. Most of the animal experimental studies reported the beneficial effects of lithium in defective bones but not in healthy bones. In humans, the effects of lithium on bones remain heterogeneous. Mechanistically, lithium promotes osteoblastic activities by activating canonical Wingless (Wnt)/beta (β)-catenin, phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) and bone morphogenetic protein-2 (BMP-2) transduction pathways but suppresses osteoclastic activities by inhibiting the receptor activator of nuclear factor-kappa B (RANK)/receptor activator of nuclear factor-kappa B ligand (RANKL)/osteoprotegerin (OPG) system, nuclear factor-kappa B (NF-κB), mitogen-activated protein kinase (MAPK), and calcium signaling cascades. In conclusion, lithium confers protection to the skeleton but its clinical utility awaits further validation from human clinical trials.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  8. Jabbarzadeh Kaboli P, Leong MP, Ismail P, Ling KH
    Pharmacol Rep, 2019 Feb;71(1):13-23.
    PMID: 30343043 DOI: 10.1016/j.pharep.2018.07.005
    BACKGROUND: Berberine is an alkaloid plant-based DNA intercalator that affects gene regulation, particularly expression of oncogenic and tumor suppressor proteins. The effects of berberine on different signaling proteins remains to be elucidated. The present study aimed to identify the effects of berberine against key oncogenic proteins in breast cancer cells.

    METHODS: Molecular docking and molecular dynamics simulations were used for EGFR, p38, ERK1/2, and AKT. The effects of berberine and lapatinib on MAPK and PI3K pathways in MDA-MB231 and MCF-7 cells were evaluated using immunoflorescence assays, and the amounts of phosphorylated kinases were compared to total kinases after treating with different concentrations of berberine.

    RESULTS: Simulations showed berberine accurately interacted with EGFR, AKT, P38, and ERK1/2 active sites in silico (scores = -7.57 to -7.92 Kcal/mol) and decreased the levels of active forms of corresponding enzymes in both cell lines; however, berberine binding to p38 showed less stability. Cytotoxicity analysis indicated that MDA-MB231 cells were resistant to berberine compared to MCF-7 cells [72 h IC50 = 50 versus 15 μM, respectively). Also, lapatinib strongly activated AKT but suppressed EGFR in MDA-MB231 cells. The activity of EGFR, AKT, P38, and ERK1/2 were affected by berberine; however, berberine dramatically reduced EGFR and AKT phosphorylation.

    CONCLUSION: By way of its multikinase inhibitory effects, berberine might be a useful replacement for lapatinib, an EGFR inhibitor which can cause acquired drug resistance in patients.

    Matched MeSH terms: Proto-Oncogene Proteins c-akt/antagonists & inhibitors*; Proto-Oncogene Proteins c-akt/metabolism; Proto-Oncogene Proteins c-akt/chemistry
  9. Sawai S, Wong PF, Ramasamy TS
    Crit Rev Biochem Mol Biol, 2022 Aug;57(4):351-376.
    PMID: 35900938 DOI: 10.1080/10409238.2022.2088684
    Hypoxia is a common feature of the tumor microenvironment (TME) of nearly all solid tumors, leading to therapeutic failure. The changes in stiffness of the extracellular matrix (ECM), pH gradients, and chemical balance that contribute to multiple cancer hallmarks are closely regulated by intratumoral oxygen tension via its primary mediators, hypoxia-inducible factors (HIFs). HIFs, especially HIF-1α, influence these changes in the TME by regulating vital cancer-associated signaling pathways and cellular processes including MAPK/ERK, NF-κB, STAT3, PI3K/Akt, Wnt, p53, and glycolysis. Interestingly, research has revealed the involvement of epigenetic regulation by hypoxia-regulated microRNAs (HRMs) of downstream target genes involved in these signaling. Through literature search and analysis, we identified 48 HRMs that have a functional role in the regulation of 5 key cellular processes: proliferation, metabolism, survival, invasion and migration, and immunoregulation in various cancers in hypoxic condition. Among these HRMs, 17 were identified to be directly associated with HIFs which include miR-135b, miR-145, miR-155, miR-181a, miR-182, miR-210, miR-224, miR-301a, and miR-675-5p as oncomiRNAs, and miR-100-5p, miR-138, miR-138-5p, miR-153, miR-22, miR-338-3p, miR-519d-3p, and miR-548an as tumor suppressor miRNAs. These HRMs serve as a potential lead in the development of miRNA-based targeted therapy for advanced solid tumors. Future development of combined HIF-targeted and miRNA-targeted therapy is possible, which requires comprehensive profiling of HIFs-HRMs regulatory network, and improved formula of the delivery vehicles to enhance the therapeutic kinetics of the targeted cancer therapy (TCT) moving forward.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  10. Chai JW, Lim SL, Kanthimathi MS, Kuppusamy UR
    Genes Nutr, 2011 May;6(2):181-8.
    PMID: 21484150 DOI: 10.1007/s12263-010-0196-4
    The nutraceutical benefits of β-sitosterol (SIT) are well documented. The present study investigated the in vitro effects of SIT on adipogenesis, glucose transport, and lipid mobilization in rat adipocytes. Primary cultures of rat preadipocytes and differentiated adipocytes were used in this study. Glucose uptake was measured by the uptake of radio-labeled glucose. Adipogenesis and lipolysis were measured by oil-red-O and glycerol quantification methods, respectively. The expression of protein kinase B (Akt), glucose transporter 4 (GLUT4), hormone sensitive lipase (HSL), and phosphatidylinositol-3-kinase (PI3 K) genes in SIT-treated adipocytes were assessed by real-time reverse transcription polymerase chain reaction (RT-PCR). The data showed that SIT induced glucose uptake in adipocytes. It also stimulated adipogenesis in differentiating preadipocytes. Interestingly, although SIT displayed general insulin-mimetic activity by stimulating glucose uptake and adipogenesis, it also induced lipolysis in adipocytes. Furthermore, the SIT-induced lipolysis was not attenuated by insulin and co-incubation of SIT with epinephrine improved epinephrine-induced lipolysis. GLUT4 gene expression was highly down-regulated in SIT-treated adipocytes, compared to insulin-treated adipocytes, which was up-regulated. Insulin- and SIT-treated adipocytes showed similar levels of Akt, HSL, and PI3 K gene down-regulation. These observations suggest that the elevation of glucose uptake in SIT-treated adipocytes was unrelated to de novo synthesis of GLUT4 and the SIT-induced lipolysis is associated with the down-regulation of Akt and PI3K genes. The unique effects of SIT on the regulation of glucose uptake, adipogenesis, and lipolysis in adipocytes show that it has potential to be utilized in diabetes and weight management.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  11. Rami M, Ahmadi Hekmatikar A, Rahdar S, Marashi SS, Daud DMA
    Sci Rep, 2024 Mar 26;14(1):7133.
    PMID: 38531890 DOI: 10.1038/s41598-024-57119-6
    T2DM is known to cause disturbances in glucose homeostasis and negative changes in the heart muscle, while aging and diabetes are recognized risk factors for CVD. Given this, our study aims to investigate a method for controlling and managing CVDs induced by T2DM in elderly populations. To achieve this, we categorized 40 rats into 5 groups, including HAD (n = 8), HA (n = 8), AD (n = 8), AHT (n = 8), and ADT (n = 8). The exercise protocol consisted of eight weeks of HIIT (three sessions per week) performed at 90-95% of maximal speed. Following cardiac tissue extraction, we assessed the levels of IGF-1, PI3K, and AKT proteins using Western blot technique, and analyzed the histopathological variations of the heart tissue using H&E, Sudan Black, and Masson's trichrome tissue staining. The histological findings from our study demonstrated that T2DM had a significant impact on the development of pathological hypertrophy and fibrosis in the heart tissue of elderly individuals. However, HIIT not only effectively controlled pathological hypertrophy and fibrosis, but also induced physiological hypertrophy in the AHT and ADT groups compared to the HA and AD groups. Results from Sudan Black staining indicated that there was an increase in lipid droplet accumulation in the cytoplasm of cardiomyocytes and their nuclei in the HA and AD groups, while the accumulation of lipid droplets decreased significantly in the AHT and ADT groups. In both the AHT group and the ADT group, a single HIIT session led to a reduction in collagen fiber accumulation and fibrotic frameworks. Our research also revealed that diabetes caused a significant elevation in the levels of IGF-1, PI3K, and AKT proteins, but after eight weeks of HIIT, the levels of these proteins decreased significantly in the training groups. Overall, our findings suggest that HIIT may be a suitable non-pharmacological approach for improving histological and physiological changes in elderly individuals with T2DM. However, we recommend further research to examine the impact of HIIT training on both healthy and diseased elderly populations.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  12. Safi SZ, Batumalaie K, Qvist R, Mohd Yusof K, Ismail IS
    PMID: 27034691 DOI: 10.1155/2016/5843615
    Purpose. Type 2 diabetes consists of progressive hyperglycemia and insulin resistance, which could result from glucose toxicity, inflammatory cytokines, and oxidative stress. In the present study we investigated the effect of Gelam honey and quercetin on the oxidative stress-induced inflammatory pathways and the proinflammatory cytokines. Methods. HIT-T15 cells were cultured and preincubated with the extract of Gelam honey (20, 40, 60, and 80 μg/mL), as well as quercetin (20, 40, 60, and 80 μM), prior to stimulation by 20 and 50 mM glucose. Results. HIT-T15 cells cultured under hyperglycemic condition showed a significant increase in the inflammatory pathways by phosphorylating JNK, IKK-β, and IRS-1 at Ser307 (p < 0.05). There was a significant decrease in the phosphorylation of Akt at Ser473 (p < 0.05). Pretreatment with Gelam honey and quercetin reduced the expression of phosphorylated JNK, IKK-β, and IRS-1, thereby significantly reducing the expression of proinflammatory cytokines like TNF-α, IL-6, and IL-1β (p < 0.05). At the same time there was a significant increase in the phosphorylated Akt showing the protective effects against inflammation and insulin resistance (p < 0.05). In conclusion, our data suggest the potential use of the extract from Gelam honey and quercetin in modulating the inflammation induced insulin signaling pathways.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  13. Md Zamri ND, Imam MU, Abd Ghafar SA, Ismail M
    PMID: 25431609 DOI: 10.1155/2014/371907
    The antioxidant properties of germinated brown rice (GBR) are likely mediated by multiple bioactives. To test this hypothesis, HepG2 cells pretreated with GBR extracts, rich in acylated steryl glycoside (ASG), gamma amino butyric acid GABA), phenolics or oryzanol, were incubated with hydrogen peroxide (H2O2) and their hydroxyl radical (OH(•)) scavenging capacities and thiobarbituric acid-reactive substances (TBARS) generation were evaluated. Results showed that GBR-extracts increased OH(•) scavenging activities in both cell-free medium and posttreatment culture media, suggesting that the extracts were both direct- and indirect-acting against OH(•). The levels of TBARS in the culture medium after treatment were also reduced by all the extracts. In addition, H2O2 produced transcriptional changes in p53, JNK, p38 MAPK, AKT, BAX, and CDK4 that were inclined towards apoptosis, while GBR-extracts showed some transcriptional changes (upregulation of BAX and p53) that suggested an inclination for apoptosis although other changes (upregulation of antioxidant genes, AKT, JNK, and p38 MAPK) suggested that GBR-extracts favored survival of the HepG2 cells. Our findings show that GBR bioactive-rich extracts reduce oxidative stress through improvement in antioxidant capacity, partly mediated through transcriptional regulation of antioxidant and prosurvival genes.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  14. Tang YQ, Jaganath I, Manikam R, Sekaran SD
    PMID: 23690850 DOI: 10.1155/2013/609581
    Phyllanthus is a traditional medicinal plant that has been found to have antihepatitis, antibacterial, and anticancer properties. The present studies were to investigate the in vitro molecular mechanisms of anticancer effects of Phyllanthus (P. amarus, P. niruri, P. urinaria, and P. watsonii) plant extracts in human prostate adenocarcinoma. The cancer ten-pathway reporter array was performed and revealed that the expression of six pathway reporters were significantly decreased (Wnt, NFκB, Myc/Max, hypoxia, MAPK/ERK, and MAPK/JNK) in PC-3 cells after treatment with Phyllanthus extracts. Western blot was conducted and identified several signalling molecules that were affected in the signalling pathways including pan-Ras, c-Raf, RSK, Elk1, c-Jun, JNK1/2, p38 MAPK, c-myc, DSH, β-catenin, Akt, HIF-1α, GSK3β, NFκB p50 and p52, Bcl-2, Bax, and VEGF, in treated PC-3 cells. A proteomics-based approach, 2D gel electrophoresis, was performed, and mass spectrometry (MS/MS) results revealed that there were 72 differentially expressed proteins identified in treated PC-3 cells and were involved in tumour cell adhesion, apoptosis, glycogenesis and glycolysis, metastasis, angiogenesis, and protein synthesis and energy metabolism. Overall, these findings suggest that Phyllanthus can interfere with multiple signalling cascades involved in tumorigenesis and be used as a potential therapeutic candidate for treatment of cancer.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt
  15. Kasi RA, Moi CS, Kien YW, Yian KR, Chin NW, Yen NK, et al.
    Mol Med Rep, 2015 Mar;11(3):2262-8.
    PMID: 25411820 DOI: 10.3892/mmr.2014.2979
    para‑Phenylenediamine (p‑PD) is a potential carcinogen, and widely used in marketed hair dye formulations. In the present study, the role of the protein tyrosine kinase (PTK)/Ras/Raf/c‑Jun N‑terminal kinase (JNK) and phosphoinositide 3‑kinase (PI3k)/protein kinase B (Akt) pathways on the growth of NRK‑52E cells was investigated. The results demonstrated that p‑PD reduced cell viability in a dose‑dependent manner. The cell death due to apoptosis was confirmed by cell cycle analysis and an Annexin‑V‑fluorescein isothiocyanate binding assay. Subsequent to staining with 2',7'‑dichlorofluorescin diacetate, the treated cells demonstrated a significant increase in reactive oxygen species (ROS) generation compared with the controls. The effects of p‑PD on the signalling pathways were analysed by western blotting. p‑PD‑treated cells exhibited an upregulated phospho‑stress‑activated protein kinase/JNK protein expression level and downregulated Ras and Raf protein expression levels; however, Akt, Bcl‑2, Bcl‑XL and Bad protein expression levels were not significantly altered compared with the control. In conclusion, p‑PD induced apoptosis by a PTK/Ras/Raf/JNK‑dependent pathway and was independent of the PI3K/Akt pathway in NRK‑52E cells.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt/metabolism
  16. Tor YS, Yazan LS, Foo JB, Armania N, Cheah YK, Abdullah R, et al.
    PMID: 24524627 DOI: 10.1186/1472-6882-14-55
    Breast cancer is one of the most dreading types of cancer among women. Herbal medicine has becoming a potential source of treatment for breast cancer. Herbal plant Dillenia suffruticosa (Griff) Martelli under the family Dilleniaceae has been traditionally used to treat cancerous growth. In this study, the anticancer effect of ethyl acetate extract of D. suffruticosa (EADs) was examined on human breast adenocarcinoma cell line MCF-7 and the molecular pathway involved was elucidated.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt/metabolism
  17. Asmaa MJ, Al-Jamal HA, Ang CY, Asan JM, Seeni A, Johan MF
    Asian Pac J Cancer Prev, 2014;15(1):475-81.
    PMID: 24528077
    BACKGROUND: Pereskia sacharosa is a genus of cacti widely used in folk medicine for cancer-related treatment. Anti-proliferative effects have been studied in recent years against colon, breast, cervical and lung cancer cell lines, with promising results. We here extended study of anti-proliferative effects to a blood malignancy, leukemia.

    MATERIALS AND METHODS: Two leukemic cell lines, MV4-11 (acute myeloid leukemia) and K562 (chronic myeloid leukemia), were studied. IC50 concentrations were determined and apoptosis and cell cycle regulation were studied by flow cytometric analysis. The expression of apoptosis and cell-cycle related regulatory proteins was assessed by Western blotting.

    RESULTS: P sacharosa inhibited growth of MV4-11 and K562 cells in a dose-dependent manner. The mode of cell death was via induction of intrinsic apoptotic pathways and cell cycle arrest. There was profound up-regulation of cytochrome c, caspases, p21 and p53 expression and repression of Akt and Bcl-2 expression in treated cells.

    CONCLUSIONS: These results suggest that P sacharosa induces leukemic cell death via apoptosis induction and changes in cell cycle checkpoint, thus deserves further study for anti-leukemic potential.

    Matched MeSH terms: Proto-Oncogene Proteins c-akt/metabolism
  18. Subramaniam KS, Tham ST, Mohamed Z, Woo YL, Mat Adenan NA, Chung I
    PLoS One, 2013;8(7):e68923.
    PMID: 23922669 DOI: 10.1371/journal.pone.0068923
    Endometrial cancer is the most commonly diagnosed gynecologic malignancy worldwide; yet the tumor microenvironment, especially the fibroblast cells surrounding the cancer cells, is poorly understood. We established four primary cultures of fibroblasts from human endometrial cancer tissues (cancer-associated fibroblasts, CAFs) using antibody-conjugated magnetic bead isolation. These relatively homogenous fibroblast cultures expressed fibroblast markers (CD90, vimentin and alpha-smooth muscle actin) and hormonal (estrogen and progesterone) receptors. Conditioned media collected from CAFs induced a dose-dependent proliferation of both primary cultures and cell lines of endometrial cancer in vitro (175%) when compared to non-treated cells, in contrast to those from normal endometrial fibroblast cell line (51%) (P<0.0001). These effects were not observed in fibroblast culture derived from benign endometrial hyperplasia tissues, indicating the specificity of CAFs in affecting endometrial cancer cell proliferation. To determine the mechanism underlying the differential fibroblast effects, we compared the activation of PI3K/Akt and MAPK/Erk pathways in endometrial cancer cells following treatment with normal fibroblasts- and CAFs-conditioned media. Western blot analysis showed that the expression of both phosphorylated forms of Akt and Erk were significantly down-regulated in normal fibroblasts-treated cells, but were up-regulated/maintained in CAFs-treated cells. Treatment with specific inhibitors LY294002 and U0126 reversed the CAFs-mediated cell proliferation (P<0.0001), suggesting for a role of these pathways in modulating endometrial cancer cell proliferation. Rapamycin, which targets a downstream molecule in PI3K pathway (mTOR), also suppressed CAFs-induced cell proliferation by inducing apoptosis. Cytokine profiling analysis revealed that CAFs secrete higher levels of macrophage chemoattractant protein (MCP)-1, interleukin (IL)-6, IL-8, RANTES and vascular endothelial growth factor (VEGF) than normal fibroblasts. Our data suggests that in contrast to normal fibroblasts, CAFs may exhibit a pro-tumorigenic effect in the progression of endometrial cancer, and PI3K/Akt and MAPK/Erk signaling may represent critical regulators in how endometrial cancer cells respond to their microenvironment.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt/metabolism
  19. Phan CW, Sabaratnam V, Bovicelli P, Righi G, Saso L
    Biofactors, 2016 Nov 12;42(6):591-599.
    PMID: 27193378 DOI: 10.1002/biof.1296
    Negletein has been shown to have therapeutic potential for inflammation-associated diseases, but its effect on neurite outgrowth is still unknown. The present study showed that negletein alone did not trigger PC12 cells to differentiate and extend neurites. When compared with the cells in the untreated control, a significant (P Akt), and cAMP response element-binding protein (CREB). The growth associated protein-43 (GAP-43) and the NGF level were also upregulated by negletein (10 µM) and a low dose of NGF (5 ng/mL). Negletein at nanomolar concentration also was found to be sufficient to mediate the survival of serum-deprived PC12 cells up to 72 h. Taken together, negletein might be useful as an efficient bioactive compound to protect neurons from cell death and promote neuritogenesis. © 2016 BioFactors, 42(6):591-599, 2016.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt/metabolism
  20. Phang CW, Karsani SA, Sethi G, Abd Malek SN
    PLoS One, 2016;11(2):e0148775.
    PMID: 26859847 DOI: 10.1371/journal.pone.0148775
    Flavokawain C (FKC) is a naturally occurring chalcone which can be found in Kava (Piper methysticum Forst) root. The present study evaluated the effect of FKC on the growth of various human cancer cell lines and the underlying associated mechanisms. FKC showed higher cytotoxic activity against HCT 116 cells in a time- and dose-dependent manner in comparison to other cell lines (MCF-7, HT-29, A549 and CaSki), with minimal toxicity on normal human colon cells. The apoptosis-inducing capability of FKC on HCT 116 cells was evidenced by cell shrinkage, chromatin condensation, DNA fragmentation and increased phosphatidylserine externalization. FKC was found to disrupt mitochondrial membrane potential, resulting in the release of Smac/DIABLO, AIF and cytochrome c into the cytoplasm. Our results also revealed that FKC induced intrinsic and extrinsic apoptosis via upregulation of the levels of pro-apoptotic proteins (Bak) and death receptors (DR5), while downregulation of the levels of anti-apoptotic proteins (XIAP, cIAP-1, c-FlipL, Bcl-xL and survivin), resulting in the activation of caspase-3, -8 and -9 and cleavage of poly(ADP-ribose) polymerase (PARP). FKC was also found to cause endoplasmic reticulum (ER) stress, as suggested by the elevation of GADD153 protein after FKC treatment. After the cells were exposed to FKC (60μM) over 18hrs, there was a substantial increase in the phosphorylation of ERK 1/2. The expression of phosphorylated Akt was also reduced. FKC also caused cell cycle arrest in the S phase in HCT 116 cells in a time- and dose-dependent manner and with accumulation of cells in the sub-G1 phase. This was accompanied by the downregulation of cyclin-dependent kinases (CDK2 and CDK4), consistent with the upregulation of CDK inhibitors (p21Cip1 and p27Kip1), and hypophosphorylation of Rb.
    Matched MeSH terms: Proto-Oncogene Proteins c-akt/metabolism
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links