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SCT60103 Group 2 Presentation
- 1. THERAPEUTIC STRATEGIES THAT ARE EMPLOYED TO TARGET THE CELLULAR TRANSFORMATION PROCESS FOR CANCER PREVENTION AND TREATMENT SCT60103 Genes & Tissue Culture Technology By Ang Jing Jie | Ho Min Min | Isaac Looi| Low Shin Yi | Nicholas Gan CELLULAR TRANSFORMATION SUICIDEGENE THERAPY
- 2. Series of events that promotes & results in (immortalisation, aberrant growth control & malignancy) Alters the cell line property (growth rate, life span & tumourigenecity) Cancer arises through a multistep process (carcinogenesis) involving: CELLULAR TRANSFORMATION Development of Cell Transformation Assay (CTA): Investigating tumour initiation / promotion activity Studying mechanisms of action of specific carcinogenic agents Developing therapeutic strategies to treat & prevent cancer (Freshney et al. 2016) (Klaunig & Kamendulis 1999) (Creton et al. 2011) (Kim et al. 2017) Virus infection Gene transfection Chemical carcinogens Ionising radiation Tumour microenvironment Tumour disorganisation
- 3. CELLULAR TRANSFORMATIONSUICIDE GENE THERAPY Express suicide gene that selectively target cancer cells The normal cells are not affected Established as anti-vascular endothelial treatment & as immune stimulator More efficient in chemotherapy resistant cancer cell lines Enhanced radiotherapy Cancer Gene Therapy Introduce foreign nucleic acids to tumour cells Immune Stimulation Gene Correction Tumour Cell Killing (Duarte et al. 2012; Pahle 2018; Zarogoulidis et al. 2013)
- 4. Tumour cell Tumour cell dies Suicide gene Prodrug conversion to toxic metabolite 1 2Targeted Gene Delivery Prodrug administration The introduction of a into tumour cells encodes enzyme that metabolises non-toxic drug into lethal drug subsequently killing tumour cells Aims to: Maximise the cytotoxic effect of a toxic drug Minimise its systemic effect by generating the drug in situ (in the appropriate position) within the tumour CELLULAR TRANSFORMATIONMECHANISMS Bystander Effect (Dey & Evans 2011; Duarte et al. 2012; Karjoo, Chen & Hatefi 2016; Springer & Niculescu-Duvaz 2000) Tumours can be eradicated even when only of the neoplastic cells are transduced with suicide gene
- 5. CELLULAR TRANSFORMATIONSUICIDE GENE SYSTEM The two most prominent systems: Prodrug 5-Fluorocytosine (5-FC) CD 5-Fluorouracil (5-FU) Ganciclovir (GCV) HSV−tk ganciclovir monophosphate ganciclovir triphosphate Pillars of suicide gene therapy: High KCAT & low Km Less cytotoxic than active drug Chemically stable Suitable substrate for the activating enzyme Diffuse readily in the tumour interstitium HSV-tk/GCV CD/5-FC Ganciclovir triphosphate 5-Fluorouracil HSV-tk/GCV CD/5-FC Tumour cell Conversion Cell Death Block DNA Synthesis S & G2 Phase Arrest Mitochondrial Damage HSV−tk Guanylate kinase Nucleoside diphosphate kinase (Dey & Evans 2011; Duarte et al. 2012; Karjoo, Chen & Hatefi 2016; Springer & Niculescu-Duvaz 2000)
- 6. CELLULAR TRANSFORMATIONBYSTANDER EFFECT Divided into 2 categories: Regression of tumour cells (transduced & untransduced) Induce tumour cell death Regression of untransduced tumours in distant from the transfected tumours Killing tumour cells treatment of metastatic cancers CD/5-FC HSV-tk/GCV HSV-tk/GCV HSV-tk/GCV HSV-tk/GCV CD/5-FC (Zhang, Kale & Chen 2015)
- 7. Delivery System Non-viral vectors Nanoparticles Cellular vehicles Bone marrow stromal cells & Neural stem cells Naked DNA Viral vectors Poxviruses, retrovirus, herpes simplex virus, adenovirus and adeno- associated viruses CELLULAR TRANSFORMATIONDELIVERY SYSTEM (Kumar & Gonipath 2016; Zarogoulidis et al. 2013)
- 8. CELLULAR TRANSFORMATIONCURRENT DEVELOPMENT Mesenchymal Stem Cells (MSCs) Suicide Gene Exosomes Nanosized lipid vesicles (30 - 120 nm) secreted by MSCs Mediate Delivering functional biomolecules (mRNA, miRNA) into recipient cells Easily communicate with cancer cells Sustain tumour cell tropism Easier to preserve and be transferred, Have no immunogenicity, Safer for therapeutic administration in comparison with exogenous MSCs Isolation & expansion of MSCs from various tissues Infection of MSCs with retrovirus carrying yCD::UPRT suicide genes The engineered MSCs released exosomes into conditioned medium (CM) Harvesting of the CM Isolation of biologically active exosomes processing mRNA of suicide gene in their cargo Addition of the CM containing these exosomes to tumour cells Tumour cell growth inhibition (Altanerova et al. 2017) (Altanerova et al. 2019) yCD::UPRT: yeast cytosine deaminase::uracil phosphoribosyl transferase
- 9. CELLULAR TRANSFORMATIONCHALLENGES Optimal Transgene Expression Bystander Effect Overcoming Immune Barriers Pre-existing immunity either due to natural infection / vaccination Neutralizing antibody responses following repeated viral vector administrations can reduce therapeutic efficiency The cancer (tumour)-specific promoters most often do not have enough transcriptional power Tumor tissues usually lack highly ordered cell junctions Construction of chimeric and artificial promoters Expression of connexin that is responsible for producing gap junctions The use of a heterologous prime-boosting regimen Temporary immunosuppression (Das et al. 2014; Karjoo, Chen & Hatefi 2016; Wu et al. 2016)
- 10. CELLULAR TRANSFORMATIONCOMBINATION THERAPY The only curative treatment for haematological malignancies (blood cancer) Patient receives blood-forming stem cells for a genetically similar but not identical donor Dependent on the donor immune system (alloreactive T-cells) Promote beneficial Donor cells attack any of the recipient's cancer cells that may remain after chemotherapy May trigger Donor cells view the recipient’s cells as foreign & attack them Transfer of suicide gene into donor lymphocytes Preserving anti-tumoural effect 1. Lymphoapheresis 2. Transduction with a vector encoding: A suicide gene A selection marker 3. Selection of transduced cells 4. Infusion of donor lymphocytes expressing the suicide gene 5. Possible clinical outcomes: 6. Administration of prodrug (Ferrara et al. 2009; Greco et al. 2015; Nienhuis 2008; Ringdén et al. 2009 )
- 11. CELLULAR TRANSFORMATIONCONCLUSION A method of choice to ablate cells in many diseases including cancer, but not fully safe and efficacious Vectors (mesenchymal stem cells, viral vectors & free DNA) are used to allow specific delivery of suicide genes to the cancer environment Distant bystander effect secure the body in case of in vivo oncogenic transformation Merely 45 clinical trials in phase III; 1 in phase IV None entered to clinical use Due to low transduction rate of the vectors (cells at the inner layers of firm and dense tumors are hard to get into reach) Development of effective vectors and targeted gene transfer to the tumour cells Design of prodrugs that can be efficiently converted into cytotoxic drugs Modification of enzymes with low immunogenicity and high affinity towards prodrugs
- 12. REFERENCES Altanerova, U, Jakubechova, J, Repiska, V & Altaner, C 2017. Exosomes of human mesenchymal stem/stromal/medicinal signaling cells. Neoplasma, vol. 64, no. 6, pp.809-815. Altanerova, U, Jakubechova, J, Benejova, K, Priscakova, P, Pesta, M, Pitule, P, Topolcan, O, Kausitz, J, Zduriencikova, M, Repiska, V & Altaner, C 2019. Prodrug suicide gene therapy for cancer targeted intracellular by mesenchymal stem cell exosomes. International journal of cancer, vol. 144, no. 4, pp.897-908. Creton, S, Aardema, MJ, Carmichael, PL, Harvey, JS, Martin, FL, Newbold, RF, O’donovan, MR, Pant, K, Poth, A, Sakai, A & Sasaki, K 2011. Cell transformation assays for prediction of carcinogenic potential: state of the science and future research needs. Mutagenesis, vol. 27, no. 1, pp.93-101. Das, S, Menezes, M, Bhatia, S, Wang, X, Emdad, L, Sarkar, D & Fisher, P 2014. Gene Therapies for Cancer: Strategies, Challenges and Successes. Journal of Cellular Physiology, vol. 230, no. 2, pp. 259-271. Dey, D & Evans, G 2011. Suicide Gene Therapy by Herpes Simplex Virus-1 Thymidine Kinase (HSV-TK). Targets in Gene Therapy. Duarte, S, Carle, G, Faneca, H, De Lima, MCP & Pierrefite-Carle, V 2012. Suicide gene therapy in cancer: where do we stand now?. Cancer letters, vol. 324, no. 2, pp.160-170. Ferrara, JL, Levine, JE, Reddy, P & Holler, E 2009. Graft-versus-host disease. The Lancet, vol. 373, no. 9674, pp.1550-1561. Freshney, RI, Capes-Davis, A, Gregory, C & Przyborski, S 2016, Culture of Animal Cells : A Manual of Basic Technique and Specialized Applications, 7th edn, Wiley-Blackwell, Hoboken, New Jersey. Greco, R, Oliveira, G, Stanghellini, MTL, Vago, L, Bondanza, A, Peccatori, J, Cieri, N, Marktel, S, Mastaglio, S, Bordignon, C & Bonini, C 2015. Improving the safety of cell therapy with the TK-suicide gene. Frontiers in pharmacology, vol. 6, p.95.
- 13. Karjoo, Z, Chen, X & Hatefi, A 2016. Progress and problems with the use of suicide genes for targeted cancer therapy. Advanced Drug Delivery Reviews, vol. 99, pp. 113-128. Kim, KW, Lee, SJ, Kim, WY, Seo, JH & Lee, HY 2017. How Can We Treat Cancer Disease Not Cancer Cells?. Cancer research and treatment: official journal of Korean Cancer Association, vol. 49, no. 1, p.1. Kumar SU & Gopinath P 2016. Nanotechnology- A Promising Approach for Suicide Gene Therapy. Austin Journal of Nanomedicine & Nanotechnology, vol. 4, no. 1, pp. 1-3. Nienhuis, AW 2008. Development of gene therapy for blood disorders. Blood, vol. 111, no. 9, pp.4431-4444. Pahle, J 2018. Oncoleaking gene therapy: a new suicide approach for treatment of pancreatic cancer. Doctorate. Humboldt University of Berlin. Ringdén, O, Karlsson, H, Olsson, R, Omazic, B & Uhlin, M 2009. The allogeneic graft‐versus‐cancer effect. British journal of haematology, vol. 147, no. 5, pp.614-633. Springer, C & Niculescu-Duvaz, I 2000. Prodrug-activating systems in suicide gene therapy. Journal of Clinical Investigation, vol. 105, no. 9, pp. 1161-1167. Wu, L, Zhou, W, Shen, F, Liu, W, Wu, H, Zhou, S & Li, S 2016. Connexin32-mediated antitumor effects of suicide gene therapy against hepatocellular carcinoma: In vitro and in vivo anticancer activity. Molecular Medicine Reports, vol. 13, no. 4, pp. 3213-3219. Zarogoulidis, P, Darwiche, K, Sakkas, A, Yarmus, L, Huang, H, Li, Q, Freitag, L, Zarogoulidis, K & Malecki, M 2013. Suicide gene therapy for cancer–current strategies. Journal of genetic syndrome & gene therapy, vol. 4. Zhang, J, Kale, V & Chen, M 2015. Gene-directed enzyme prodrug therapy. The AAPS journal, vol. 17, no. 1, pp.102-110.