Browsing by Author "Zerbini, Luiz F"
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- ItemOpen AccessCombinatorial effect of non-steroidal anti-inflammatory drugs and NF-kappaB inhibitors in ovarian cancer therapy(Public Library of Science, 2011) Zerbini, Luiz F; Tamura, Rodrigo E; Correa, Ricardo G; Czibere, Akos; Cordeiro, Jason; Bhasin, Manoj; Simabuco, Fernando M; Wang, Yihong; Gu, Xuesong; Li, LinglinSeveral epidemiological studies have correlated the use of non-steroidal anti-inflammatory drugs (NSAID) with reduced risk of ovarian cancer, the most lethal gynecological cancer, diagnosed usually in late stages of the disease. We have previously established that the pro-apoptotic cytokine melanoma differentiation associated gene-7/Interleukin-24 ( mda -7/IL-24) is a crucial mediator of NSAID-induced apoptosis in prostate, breast, renal and stomach cancer cells. In this report we evaluated various structurally different NSAIDs for their efficacies to induce apoptosis and mda -7/IL-24 expression in ovarian cancer cells. While several NSAIDs induced apoptosis, Sulindac Sulfide and Diclofenac most potently induced apoptosis and reduced tumor growth. A combination of these agents results in a synergistic effect. Furthermore, mda -7/IL-24 induction by NSAIDs is essential for programmed cell death, since inhibition of mda -7/IL-24 by small interfering RNA abrogates apoptosis. mda -7/IL-24 activation leads to upregulation of growth arrest and DNA damage inducible (GADD) 45 α and γ and JNK activation. The NF-κB family of transcription factors has been implicated in ovarian cancer development. We previously established NF-κB/IκB signaling as an essential step for cell survival in cancer cells and hypothesized that targeting NF-κB could potentiate NSAID-mediated apoptosis induction in ovarian cancer cells. Indeed, combining NSAID treatment with NF-κB inhibitors led to enhanced apoptosis induction. Our results indicate that inhibition of NF-κB in combination with activation of mda -7/IL-24 expression may lead to a new combinatorial therapy for ovarian cancer.
- ItemOpen AccessComputer-aided drug design and the biological evaluation of anti-cancer drugs(2016) Moorad, Razia; Zerbini, Luiz F; Chibale, KellyComputer-aided drug design has become a promising alternative to high-throughput screening by identifying potential hits in silico for in vitro evaluation. In this study a combination of ligand-based and structure-based virtual screening was performed to identify in silico hits. This was based on finding similar inhibitors to 6-amino-4-(4-phenoxyphenylethylamino) quinazoline, a potent inhibitor of the Nuclear Factor kappa B (NF-κB), a transcription factor that has a pivotal role in cancer survival and Pentamidine, an anti-parasitic drug that has recently been demonstrated to possess tumour-killing activity. A hierarchical methodology consisting of a similarity search followed by structure-based virtual screening of the ZINC database was performed. In order to perform the docking studies, binding sites for 6-amino-4-(4-phenoxyphenylethylamino) quinazoline on the NF-κB/IκBα complex were identified through blind docking. In addition, the National Cancer Institute (NCI) database was screened, utilising existing structure-activity relationship data from literature. A pharmacophore search was designed to test the hypothesis of the structural features necessary for activity as seen with quinazoline inhibitors of NF-κB. No virtual hits from the ZINC database were confirmed with in vitro activity. On the other hand, three compounds identified from the pharmacophore search were confirmed to inhibit cancer cell proliferation in vitro, with compound NSC727152 demonstrating the most potent activity. In order to determine if NSC727152 acted similarly to 6-amino-4-(4-phenoxyphenylethylamino) quinazoline by inhibiting NF-κB, the effects of NSC727152 on the expression of NF-κB targeted genes, including the Growth Arrest and DNA Damage 45 (GADD45) α and γ and the Interleukin 6 (IL-6) genes were evaluated. GADD45 α and γ have been shown to be regulated by NF-κB during cancer progression and aberrant IL-6 gene expression has been implicated in cancer progression and mortality and its expression is at least partially mediated via constitutive activation of NF-κB. In this study, it has been demonstrated that GADD45 α and γ are upregulated after treatment with NSC727152. A down-regulation of the IL-6 promoter activity and mRNA expression in cancer cells treated with NSC727152 has also been demonstrated in this study. However, no hits similar to Pentamidine were confirmed with in vitro activity. In conclusion, the compound NSC727152 has been shown to inhibit NF-κB and further analysis is necessary to determine its full potential as an NF-κB inhibitor.
- ItemOpen AccessNovel urinary and serological markers of prostate cancer using proteomics techniques: an important tool for early cancer diagnosis and treatment monitoring(2016) Adeola, Henry Ademola; Zerbini, Luiz F; Blackburn, Jonathan MIn Africa, Prostate cancer (PCa) is the most frequently diagnosed solid organ tumour in males and use of prostate specific antigen (PSA) is presently fraught with diagnostic inaccuracies. Not least, in a multi-ethnic society like South Africa, proteome differences between African, Caucasian and Mixed-Ancestry PCa patients are largely unknown. Hence, discovery and validation of affordable, non-invasive and reliable diagnostic biomarkers of PCa would expand the frontiers of PCa management. We have employed two high-throughput proteomics technologies to identify novel urine- and blood-based biomarkers for early diagnosis and treatment monitoring of prostate cancer in a South African cohort as well as elucidate proteome differences in patients from our heterogeneous cohort. We compared the urinary proteomes of PCa, Benign Prostatic Hyperplasia (BPH), disease controls comprising patients with other uropathies (DC) and normal healthy controls (NC) both by pooling and individual discovery shotgun proteomic assessment on a nano-Liquid chromatography (nLC) coupled Hybrid Quadrupole-Orbitrap Mass Spectrometer platform. In-silico verification of identified biomarkers was performed using the Human Protein Atlas (HPA) as well as SRMAtlas; and verified potential biomarkers were experimentally prevalidated using a targeted parallel reaction monitoring (PRM) proteomics approach. Further, we employed the CT100+ antigen microarray platform to assess the differential humoral antibody response of PCa, DC and BPH patients in our cohort to a panel of 123 tumour-associated cancer antigens. Candidate antigen biomarkers were analyzed for ethnic group variation in our cohort and potential cancer diagnostic and immunotherapeutic inferences were drawn. Using these approaches, we identified 5595 and 9991 non-redundant peptides from the pooled and individual experiments respectively. While nine proteins demonstrated ethnic trend, 37 and 73 proteins were differentially expressed by pooled and individual analysis respectively. All 32 verified biomarkers were prevalidated with parallel reaction monitoring. Good PRM signals for 12 top ranking biomarker was observed, including PSA and prostatic acid phosphatase. We also identified 41 potential diagnostic and immunotherapeutic antigen biomarkers. Proteogenomic functional pathway analyses of differentially expressed antigens showed similar enrichments of biologic processes. We identified herein novel urinary and blood-based potential diagnostic biomarkers and immunotherapeutic targets of PCa in a South African PCa Cohort using multiple proteomics approaches.
- ItemOpen AccessThe role of Defective in Cullin Neddylation 1 Domain Containing 1 (DCUN1D1) in prostate cancer(2014) Vava, Akhona; Zerbini, Luiz FIncludes abstract. Includes bibliographical references.