1. Cancer Gene Therapy …Using Tumor Suppressor Genes.

2. Overview Gene Therapy p53 Using Gene Therapy to Treat Lung Cancer Problems

3. Gene Therapy Vectors In Vivo vs. Ex Vivo Which cells are the target cells

4. What is Gene Therapy? Gene therapy is a technique for introducing the genetic material of a gene in a patient that lacks that gene because of a mutation.

5. Vectors The way you insert the “normal” gene in the patient’s cell is by vectors. The most common vectors that are used in gene therapy are virus vectors

6. Why Viruses? Viruses through the time of evolution have evolved to infect the cells with great specificity Viruses tend to be very efficient at transfecting their own DNA into the host cell genome. This allows them to produce new viral particles at the period of synthesis of the cell

7. Types Of Viruses… Retrovirus Adinovirus Lentiviruses Poxviruses and Herpes Viruses

8. Adenovirus 36 kb Double Stranded DNA Genome Entry through CAR receptor and integrin co-receptor

9. E1A E3 E1B E2AE4E2B L1L2 L4 L3L5 Latest Generation Adenoviral Vector “Gutless”; Helper-dependent; Minimal Ad Therapeutic Transgene Stuffer DNA  ITR

10. Which Virus to Use? Depends how well they transfer the genes to cells which cells they can recognize and infect and whether they alter the cell’s DNA permanently or temporarily

11. Cells removed from body Transgene delivered Cells cultured Cells returned to the body Ex VivoIn Vivo Transgene delivered directly into host Strategies for Transgene Delivery

12. Which cells are the target cells Both Healthy and Cancerous cells can be a target Ex of targeting Healthy cells  One way is by replacing a missing or altered gene with a “normal” one

13. Cont: Which cells are the target cells Ex of targeting Cancer Cells Scientists can target cancer cells with genes that can be used to destroy the cells. In this technique, cancer cells are introduced to what is called “suicide genes”

14. Naked DNA Target Cell Therapeutic Protein AAV Retrovirus/Lentivirus Adenovirus Nucleus Gene Therapy Principles

15. Adenovirus Cell Entry

16. p53 Pathway

18. Using Gene Therapy to Treat Lung Cancer In this clinical trial the scientist used gene therapy in combination with radiation therapy so they can treat lung cancer in 19 different patients

19. Treatment: Gene therapy and Radiation. Intratumoral needle injections of Ad-p53 on days 1, 18 and 32 of the treatment. tumors ≥ 4 cm where injected with 10 ml tumors ‹ 4 cm were injected with 3 ml Radiation therapy

20. Results 17/19 patients made it through the entire therapy complete response in 2 patients (11%) partial response in 4 patients (21%) stable disease in 1 patient (5%) progressive disease in 11 patients (57%)

22. Results Not That Good 57% of the patients showed that the cancer progressed to worse stages Why?

23. Major Problems that Scientists Must Overcome Identify more efficient ways to deliver the genes to the patients’ genetic material Develop vectors that can specifically focus on the targeted cells Ensure that vectors will successfully insert the desired genes into each of these target cells

24. Cont: Major Problems that Scientists Must Overcome Deliver genes to a precise location in the patient’s DNA Ensure that transplanted genes are precisely controlled by the body’s normal physiologic signals