+ Epigenetic Regulation of Drug Metabolism Amber Frick, PharmD November 19, 2013

+ Pharmacogenomics

+ Pharmacogenomics Case You prescribed simvastatin 80 mg daily to a patient with hyperlipidemia. They return to your office with extreme muscle aches, and you suspect rhabdomyolysis. Why is the patient experiencing these side effects? What genetic and/or environmental factors may be involved? What tests should you perform? What actions should you take next? If you were designing a clinical trial for a new statin medication, what would you include in the experimental design?

+ SLCO1B1 Association with Myopathy SEARCH Collaborative Group. N Engl J Med 2008;359 SLCO1B1 Estimated Cumulative Risk of Myopathy

+ Epigenetics TED x and RadioLab

+ Epigenetics Changes in gene activity caused by mechanisms other than changes in underlying DNA sequence Patterns vary between gender, age groups, species, tissue, and cells Involves a network of layered processes: DNA methylation Histone modification Non-protein coding (nc) RNAs

+ Epigenetic Mechanisms Affect Health

+ Epigenetic Mechanisms Affect Drug Response Kacevska M, et al. Pharmacogenomics 2012;13.

+ Epigenetic Machinery Ivanov M, et al. Clinical Pharmacology and Therapeutics 2012;92.

+ DNA Methylation

+ Fifth Base of the Genome DNMT1 Read A, and Donnai D. New Clinical Genetics. Bloxham UK: Scion Publishing Ltd, 2007.

+ Sixth Base of the Genome Branco MR, et al. Nature Reviews Genetics 2012;13.

+ Aberrant DNA Methylation in Cancer Wright J. Nature 2013;498.

+ Aberrant DNA Methylation in Cancer Ivanov M, et al. Clinical Pharmacology and Therapeutics 2012;92.

+ On-Off Switch for Genes Ingelman-Sundberg M, et al. Drug Metabolism and Disposition 2013;41.

+ Epigenetic Regulation of ADME Genes Ivanov M, et al. Clinical Pharmacology and Therapeutics 2012;92.

+ Clinical Relevance of Methylation GSTP1 methylation and DNA methyltransferase inhibitor treatment of prostate cancer and doxorubicin treatment of breast cancer UGT1A1 and irinotecan treatment of colon cancer SLC19A1 and methotrexate treatment of lymphomas GPx3 and cisplatin treatment of head and neck cancer VDR and calcitriol treatment of breast cancer

+ Methylation of GSTP1 Rønneberg JA, et al. Cancer Res 2008;68.

+ DNMT Inhibitors AzacitadineDecitadine

+ Histone Modification Arrowsmith CH, et al. Nature Reviews 2012;11.

+ Histone Modification

+ HDAC and CYP3A4 Wu Y, et al. Journal of Pharmaceutical and Biomedical Analysis 2012;58.

+ HDAC Inhibitors Vorinostat Romidepsin Arrowsmith CH, et al. Nature Reviews 2012;11.

+ Non-protein coding RNAs Only 2% of the genome encodes protein-coding genes via mRNA transcripts miRNAs are the most widely studied Approximately 22 nucleotides in length Mediate post-transcriptional gene silencing Regulate the translation of >60% of protein-coding genes lncRNA targets histone-modifying enzymes to specific genomic loci DNA methylation and histone modification control miRNA levels

+ miRNAs and Drug Metabolism Kacevska M, et al. Pharmacogenomics 2012;13.

+ miRNAs and Drug Sensitivity Kacevska M, et al. Pharmacogenomics 2012;13.

+ Pleiotropic Effects of Non- Epigenetic Drugs Lotsch J. Trends in Molecular Medicine 2013.

+ Pleiotropic Effects of Non- Epigenetic Drugs Lotsch J. Trends in Molecular Medicine 2013.

+ Specificity of Epigenetic Agents Dawson MA, Kouzarides. Cell 2012;150. EPZ *IC 50 pM Range * Arrowsmith CH, et al. Nature Reviews 2012;11.

+ Specificity of Epigenetic Agents Compound 6J *IC 50 1 μM * Arrowsmith CH, et al. Nature Reviews 2012;11.

+ Specificity of Epigenetic Agents

+ Epigenetic Targets Dawson MA, Kouzarides. Cell 2012;150.

+ Full Drug Pipeline

+ Pharmacoepigenetics Case 1 CYP2W1 is polymorphic with two major allelic variants (*2 and *6). You find hypomethylation in a set of colon cancer samples. Currently, the chemotherapeutic regimens used to treat colon cancer are not tolerated well with numerous non-specific side effects. As a drug developer, what therapeutic intervention would you design? What potential issues may arise in terms of drug-drug interactions? Gomez A, Ingelman-Sundberg M. Clinical Pharmacology & Therapeutics 2009; 85.

+ Pharmacoepigenetics Case 2 Colorectal cancer cells can be made more sensitive to the effects of 5-fluorouracil with the use of lovastatin via an epigenetic mechanism. What epigenetic mechanism occurs with the administration of lovastatin? How would therapy be affected by the co-administration of epigenetics targeting therapies? How would response be affected by capecitabine administration rather than 5-fluorouracil?

+ Pharmacoepigenetics Case 3 The HDAC and DNMT inhibitors are given to the patient as long as they benefit from treatment. Given that current epigenetic reversing drugs are highly promiscuous in their drug targets: What are the likely long-term consequences of epigenetic therapeutic regulation? How does administration affect expression of drug metabolizing enzymes? What drug-drug interactions are of concern?

+ Pharmacoepigenetics Case 3 The HDAC and DNMT inhibitors are given to the patient as long as they benefit from treatment. Given that current epigenetic reversing drugs are highly promiscuous in their drug targets: What are the likely long-term consequences of epigenetic therapeutic regulation? How does administration affect expression of drug metabolizing enzymes? What drug-drug interactions are of concern?

+ Pharmacoepigenetics Case 4 miRNA therapeutics are gaining momentum. For instance, miR-122 (Miravirsin) is being investigated in hepatitis C and hepatocellular carcinoma.  Would you use miRNA-based therapy to regulate drug sensitivity or modulate drug metabolizing enzymes, drug transporters, and nuclear receptors?  What hurdles must you overcome to develop miRNA-based therapy?

+ Questions, Comments, Suggestions, or Constructive Criticism?