1 6776 110 [APPROACHING NEW PHARMACOTHERAPY OPTIONS IN PAIN TREATMENT]. THE EVOLUTION OF MEDICINE IS NOTICEABLE IN MOST THERAPEUTIC AREAS, THE WORSE THE CURRENT THERAPEUTIC RESULT, THE MORE QUICK THE IMPROVEMENT. THIS IS ESPECIALLY TRUE IN SUCH AREAS THAT REQUIRE SUBSTANTIAL SOCIAL RESOURCES, NAMELY ONCOLOGY, DIABETOLOGY AND CNS DISEASES. PAIN IS NOT A DISEASE, IT IS A SYMPTOM. PAIN IS ONE OF THE MOST IMPORTANT COMPONENTS OF HUMAN SUFFERING THUS IT DESERVES SPECIAL ATTENTION. IN RECENT YEARS NEW FORMULATIONS OF OLD MEDICINES WERE INTRODUCED RATHER THAN NEW MEDICINES. MAYBE ZICONITIDE IS THE LAST PAIN KILLER WITH NEW MECHANISM OF ACTION WHICH WAS APPROVED BY FDA IN 2004. HOWEVER, THE NEW INFORMATION AND TECHNIQUES ARE ALSO APPEARING IN THE FIELD OF ANALGESIA. NOWADAYS ONE CAN TALK ABOUT GENETIC/EPIGENETIC TARGETS, RNA THERAPIES, VOLTAGE-GATED CALCIUM CHANNELS, NEW PAIN RECEPTORS (TRPV1, TRPV4, NMDA, NAV RECEPTORS) REGARDING PAIN TREATMENT, INDICATING THAT THE PRACTICE OF THE PHARMACOTHERAPY OF PAIN WILL CHANGE FUNDAMENTALLY IN THE IMMEDIATE FUTURE. THIS PAPER IS INTENDED TO GIVE A SHORT SUMMARY OF THESE NEW OPTIONS. 2017 2 5038 21 PHARMACOGENETICS OF CHRONIC PAIN AND ITS TREATMENT. THIS PAPER REVIEWS THE IMPACT OF GENETIC VARIABILITY OF DRUG METABOLIZING ENZYMES, TRANSPORTERS, RECEPTORS, AND PATHWAYS INVOLVED IN CHRONIC PAIN PERCEPTION ON THE EFFICACY AND SAFETY OF ANALGESICS AND OTHER DRUGS USED FOR CHRONIC PAIN TREATMENT. SEVERAL CANDIDATE GENES HAVE BEEN IDENTIFIED IN THE LITERATURE, WHILE THERE IS USUALLY ONLY LIMITED CLINICAL EVIDENCE SUBSTANTIATING FOR THE PENETRATION OF THE TESTING FOR THESE CANDIDATE BIOMARKERS INTO THE CLINICAL PRACTICE. FURTHER, THE PAIN-PERCEPTION REGULATION AND MODULATION ARE STILL NOT FULLY UNDERSTOOD, AND THUS MORE COMPLEX KNOWLEDGE OF GENETIC AND EPIGENETIC BACKGROUND FOR ANALGESIA WILL BE NEEDED PRIOR TO THE CLINICAL USE OF THE CANDIDATE GENETIC BIOMARKERS. 2013 3 1291 25 DECODING THE ROLE OF EPIGENETICS AND GENOMICS IN PAIN MANAGEMENT. PERSISTENT PAIN IS A COSTLY EPIDEMIC, AFFECTING >50 MILLION AMERICANS WITH ESTIMATED EXPENDITURES OF >$200 BILLION ANNUALLY FOR DIRECT CARE AND LOST PRODUCTIVITY. RECENT ADVANCES IN EPIGENETIC/GENOMIC UNDERSTANDING OF PAIN AND ANALGESIC RESPONSE MAY LEAD TO IMPROVEMENTS IN PAIN MANAGEMENT AND HELP CURTAIL COSTS BY PROVIDING MORE PRECISE DETECTION OF THE PAIN MECHANISMS INVOLVED AND THEREBY MORE PERSONALIZED AND EFFECTIVE TREATMENTS. HOWEVER, THE TRANSLATION OF EPIGENETIC AND GENOMIC STRATEGIES FOR PAIN MANAGEMENT INTO CLINICAL PRACTICE WILL DEPEND ON UNDERSTANDING THEIR POTENTIAL APPLICATIONS. THE PURPOSE OF THIS ARTICLE IS TO EXAMINE CURRENT KNOWLEDGE ABOUT EPIGENETIC AND GENOMIC MECHANISMS OF PERSISTENT PAIN AND POTENTIAL OPPORTUNITIES FOR IMPROVING PAIN MANAGEMENT. THE INITIAL DISCUSSION FOCUSES ON PRESENT UNDERSTANDING OF NOCICEPTIVE PATHWAYS AND ALTERATIONS THAT LEAD TO PATHOLOGIC PAIN. THE DISCUSSION THEN MOVES TO A REVIEW OF EPIGENETIC MECHANISMS THAT HAVE BEEN IDENTIFIED IN THE TRANSITION TO AND MAINTENANCE OF PERSISTENT PAIN AS WELL AS IN THE INDIVIDUAL'S RESPONSE TO ANALGESICS. POTENTIAL APPLICATIONS OF EPIGENETICS/GENOMICS TO IDENTIFY PEOPLE AT RISK AND POSSIBLY PREVENT PERSISTENT PAIN AND GUIDE DIAGNOSIS AND THE SELECTION OF THERAPEUTIC MODALITIES ARE PRESENTED. 2013 4 6807 18 [EPIGENETICS AND PAIN]. CHRONIC PAIN AFFECTS APPROXIMATELY 20 % OF ADULTS WORLDWIDE AND IS OFTEN ASSOCIATED WITH A DECREASE IN THE QUALITY OF LIFE AND VARIOUS COMORBIDITIES. CONVENTIONAL ANALGESIC THERAPIES ARE FREQUENTLY INSUFFICIENT AND SOMETIMES LEAD TO SEVERE SIDE EFFECTS. THEREFORE, GREAT EFFORTS ARE STILL BEING MADE TO ELUCIDATE THE SIGNALLING PATHWAYS IN PAIN AND TO DEVELOP NEW, SAFE AND EFFECTIVE THERAPIES. EPIGENETIC MECHANISMS WHICH INTERFERE WITH THE REGULATION OF GENE EXPRESSION ARE INVOLVED IN THE PATHOGENESIS OF SEVERAL DISEASES AND ARE GAINING INCREASING IMPETUS IN MEDICAL RESEARCH. AS THEY ARE ALSO INVOLVED IN PAIN PROCESSING, A MODULATION OF THESE MECHANISMS MIGHT REPRESENT A NOVEL OPTION FOR THE THERAPY OF PAIN PATIENTS. 2014 5 1204 26 COULD TARGETING EPIGENETIC PROCESSES RELIEVE CHRONIC PAIN STATES? PURPOSE OF REVIEW: ABERRATIONS IN THE EPIGENETIC LANDSCAPE HAVE PREVIOUSLY BEEN ASSOCIATED WITH HUMAN DISEASES SUCH AS CANCER AND SCHIZOPHRENIA, AND DRUGS THAT TARGET EPIGENETIC PROCESSES ARE CURRENTLY USED AS THERAPEUTIC AGENTS. THIS ARTICLE WILL REVIEW THE EVIDENCE OBTAINED FROM ANIMAL STUDIES INDICATING THAT EPIGENETIC PROCESSES MIGHT REGULATE LONG-TERM PAIN STATES AND THEN DISCUSS THE POSSIBILITY THAT TARGETING EPIGENETIC MECHANISMS MIGHT BE USEFUL FOR THE MANAGEMENT OF CHRONIC PAIN. RECENT FINDINGS: RECENT ANIMAL STUDIES HAVE REPORTED INJURY-INDUCED CHANGES IN EPIGENETIC PROCESSES IN THE CENTRAL NERVOUS SYSTEM. THE PICTURE THAT HAS EMERGED IS THAT OF VERY COMPLEX EPIGENETIC PROGRAMS THAT DEPEND ON THE INJURY. HOWEVER, SOME STUDIES HAVE REPORTED THE SUCCESSFUL USE OF NONSPECIFIC EPIGENETIC TOOLS TO IMPROVE THE HYPERSENSITIVITY THAT DEVELOPS IN ANIMAL MODELS OF LONG-TERM PAIN STATES. SUMMARY: THE FIELD OF EPIGENETICS AND PAIN IS RAPIDLY EMERGING BUT FURTHER INVESTIGATION IS NEEDED TO FULLY COMPREHEND THE CONTRIBUTION OF EPIGENETIC PROCESSES TO CHRONIC PAIN STATES. ALTHOUGH THERAPEUTIC APPROACHES TARGETING THESE MECHANISMS MIGHT SEEM WORTHWHILE, WE CANNOT ASSERT THAT CURRENTLY AVAILABLE GLOBAL TOOLS SUCH AS HISTONE DEACETYLASE INHIBITORS CAN BE USED SUCCESSFULLY FOR THE LONG-TERM TREATMENT OF CHRONIC PAIN STATES. 2015 6 1686 27 DRUGGING THE PAIN EPIGENOME. MORE THAN 20% OF ADULTS WORLDWIDE EXPERIENCE DIFFERENT TYPES OF CHRONIC PAIN, WHICH ARE FREQUENTLY ASSOCIATED WITH SEVERAL COMORBIDITIES AND A DECREASE IN QUALITY OF LIFE. SEVERAL APPROVED PAINKILLERS ARE AVAILABLE, BUT CURRENT ANALGESICS ARE OFTEN HAMPERED BY INSUFFICIENT EFFICACY AND/OR SEVERE ADVERSE EFFECTS. CONSEQUENTLY, NOVEL STRATEGIES FOR SAFE, HIGHLY EFFICACIOUS TREATMENTS ARE HIGHLY DESIRABLE, PARTICULARLY FOR CHRONIC PAIN. EPIGENETIC MECHANISMS SUCH AS DNA METHYLATION, HISTONE MODIFICATIONS AND MICRORNAS (MIRNAS) STRONGLY AFFECT THE REGULATION OF GENE EXPRESSION, POTENTIALLY FOR LONG PERIODS OVER YEARS OR EVEN GENERATIONS, AND HAVE BEEN ASSOCIATED WITH PATHOPHYSIOLOGICAL PAIN. SEVERAL STUDIES, MOSTLY IN ANIMALS, REVEALED THAT INHIBITORS OF DNA METHYLATION, ACTIVATORS AND INHIBITORS OF HISTONE MODIFICATION AND MODULATORS OF MIRNAS REVERSE A NUMBER OF PATHOLOGICAL CHANGES IN THE PAIN EPIGENOME, WHICH ARE ASSOCIATED WITH ALTERED EXPRESSION OF PAIN-RELEVANT GENES. THIS EPIGENETIC MODULATION MIGHT THEN REDUCE THE NOCICEPTIVE RESPONSE AND PROVIDE NOVEL THERAPEUTIC OPTIONS FOR ANALGESIC THERAPY OF CHRONIC PAIN STATES. HOWEVER, A NUMBER OF CHALLENGES, SUCH AS NONSPECIFIC EFFECTS AND POOR DELIVERY TO TARGET CELLS AND TISSUES, HINDER THE RAPID DEVELOPMENT OF SUCH ANALGESICS. IN THIS REVIEW, WE CRITICALLY SUMMARIZE DATA ON EPIGENETICS AND PAIN, FOCUSING ON CHALLENGES IN CLINICAL DEVELOPMENT AS WELL AS POSSIBLE NEW APPROACHES TO THE DRUG MODULATION OF THE PAIN EPIGENOME. 2017 7 2611 20 EPIGENETICS: A PROMISING PARADIGM FOR BETTER UNDERSTANDING AND MANAGING PAIN. EPIGENETIC REGULATION OF GENE EXPRESSION IS A RAPIDLY GROWING AREA OF RESEARCH. CONSIDERING THE LONGEVITY AND PLASTICITY OF NEURONS, THE STUDIES ON EPIGENETIC PATHWAYS IN THE NERVOUS SYSTEM SHOULD BE OF SPECIAL INTEREST FOR BOTH EPIGENETICISTS AND NEUROSCIENTISTS. ACTIVATION OR INACTIVATION OF DIFFERENT EPIGENETIC PATHWAYS BECOMES MORE PRONOUNCED WHEN THE CELLS EXPERIENCE RAPID CHANGES IN THEIR ENVIRONMENT, AND SUCH CHANGES CAN BE EASILY CAUSED BY INJURY AND INFLAMMATION, RESULTING IN PAIN PERCEPTION OR DISTORTION OF PAIN PERCEPTION (EG, HYPERALGESIA). THEREFORE, IN THIS REGARD, THE FIELD OF PAIN IS AT AN ADVANTAGE TO STUDY THE EPIGENETIC PATHWAYS. MORE IMPORTANTLY, UNDERSTANDING PAIN FROM AN EPIGENETICS POINT OF VIEW WOULD PROVIDE A NEW PARADIGM FOR DEVELOPING DRUGS OR STRATEGIES FOR PAIN MANAGEMENT. IN THIS REVIEW, WE INTRODUCE BASIC CONCEPTS OF EPIGENETICS, INCLUDING CHROMATIN DYNAMICS, HISTONE MODIFICATIONS, DNA METHYLATION, AND RNA-INDUCED GENE SILENCING. IN ADDITION, WE PROVIDE EVIDENCE FROM PUBLISHED STUDIES SUGGESTING WIDE IMPLICATION OF DIFFERENT EPIGENETIC PATHWAYS WITHIN PAIN PATHWAYS. PERSPECTIVE: THIS ARTICLE PROVIDES A BRIEF OVERVIEW OF EPIGENETIC PATHWAYS FOR GENE REGULATION AND HIGHLIGHTS THEIR INVOLVEMENT IN PAIN. OUR GOAL IS TO EXPOSE THE READERS TO THESE CONCEPTS SO THAT PAIN-RELATED PHENOTYPES CAN BE INVESTIGATED FROM THE EPIGENETIC POINT OF VIEW. 2013 8 5926 23 TARGETING EPIGENETIC MECHANISMS FOR CHRONIC PAIN: A VALID APPROACH FOR THE DEVELOPMENT OF NOVEL THERAPEUTICS. CHRONIC PAIN IS A MULTIFACETED AND COMPLEX CONDITION. BROADLY CLASSIFIED INTO SOMATIC, VISCERAL, OR NEUROPATHIC PAIN, IT IS POORLY MANAGED DESPITE ITS PREVALENCE. CURRENT DRUGS USED FOR THE TREATMENT OF CHRONIC PAIN ARE LIMITED BY TOLERANCE WITH LONG-TERM USE, ABUSE POTENTIAL, AND MULTIPLE ADVERSE SIDE EFFECTS. THE PERSISTENT NATURE OF PAIN SUGGESTS THAT EPIGENETIC MACHINERY MAY BE A CRITICAL FACTOR DRIVING CHRONIC PAIN. IN THIS REVIEW, WE DISCUSS THE LATEST INSIGHTS INTO EPIGENETIC PROCESSES, INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS, AND MICRORNAS, AND WE DESCRIBE THEIR INVOLVEMENT IN THE PATHOPHYSIOLOGY OF CHRONIC PAIN AND WHETHER EPIGENETIC MODIFICATIONS COULD BE APPLIED AS FUTURE THERAPEUTIC TARGETS FOR CHRONIC PAIN. WE PROVIDE EVIDENCE FROM EXPERIMENTAL MODELS AND TRANSLATIONAL RESEARCH IN HUMAN TISSUE THAT HAVE ENHANCED OUR UNDERSTANDING OF EPIGENETIC PROCESSES MEDIATING NOCICEPTION, AND WE THEN SPECULATE ON THE POTENTIAL FUTURE USE OF MORE SPECIFIC AND SELECTIVE AGENTS THAT TARGET EPIGENETIC MECHANISMS TO ATTENUATE PAIN. 2016 9 1984 20 EPIGENETIC ALTERATIONS IN PRESCRIPTION OPIOID MISUSE: NEW STRATEGIES FOR PRECISION PAIN MANAGEMENT. PRESCRIPTION OPIOIDS ARE USED FOR SOME CHRONIC PAIN CONDITIONS. HOWEVER, GENERALLY, LONG-TERM THERAPY HAS UNWANTED SIDE EFFECTS WHICH MAY TRIGGER ADDICTION, OVERDOSE, AND EVENTUALLY CAUSE DEATHS. OPIOID ADDICTION AND CHRONIC PAIN CONDITIONS HAVE BOTH BEEN ASSOCIATED WITH EVIDENCE OF GENETIC AND EPIGENETIC ALTERATIONS. DESPITE INTENSE RESEARCH INTEREST, MANY QUESTIONS ABOUT THE CONTRIBUTION OF EPIGENETIC CHANGES TO THIS TYPOLOGY OF ADDICTION VULNERABILITY AND DEVELOPMENT REMAIN UNANSWERED. THE AIM OF THIS REVIEW WAS TO SUMMARIZE THE EPIGENETIC MODIFICATIONS DETECTED IN SPECIFIC TISSUES OR BRAIN AREAS AND ASSOCIATED WITH OPIOID PRESCRIPTION AND MISUSE IN PATIENTS WHO HAVE INITIATED PRESCRIBED OPIOID MANAGEMENT FOR CHRONIC NON-CANCER PAIN. THE REVIEW CONSIDERS THE EFFECTS OF OPIOID EXPOSURE ON THE EPIGENOME IN CENTRAL AND PERIPHERAL TISSUES IN ANIMAL MODELS AND HUMAN SUBJECTS AND HIGHLIGHTS THE MECHANISMS IN WHICH OPIOID EPIGENETICS MAY BE INVOLVED. THIS WILL IMPROVE OUR CURRENT UNDERSTANDING, PROVIDE THE BASIS FOR TARGETED, PERSONALIZED PAIN MANAGEMENT, AND THUS BALANCE OPIOID RISKS AND BENEFITS IN MANAGING CHRONIC PAIN. 2021 10 6124 22 THE EPIGENETIC MECHANISMS INVOLVED IN CHRONIC PAIN IN RODENTS: A MINI- REVIEW. CHRONIC PAIN IS A COMMON DISTRESSING NEUROLOGICAL DISORDER AND ABOUT 30% OF THE GLOBAL POPULATION SUFFERS FROM IT. IN ADDITION TO BEING HIGHLY PREVALENT, CHRONIC PAIN CAUSES A HEAVY ECONOMIC AND SOCIAL BURDEN. ALTHOUGH SUBSTANTIAL PROGRESS HAS BEEN ACHIEVED TO DISSECT THE UNDERLYING MECHANISM OF CHRONIC PAIN IN THE PAST FEW DECADES, THE INCIDENCE AND TREATMENT OF THIS NEUROLOGICAL ILLNESS IS YET NOT PROPERLY MANAGED IN CLINICAL PRACTICE. WHILE NERVE INJURY-, CHEMOTHERAPY- OR INFLAMMATION-INDUCED FUNCTIONAL REGULATION OF GENE EXPRESSION IN THE DORSAL ROOT GANGLION AND SPINAL CORD ARE EXTENSIVELY REPORTED TO BE INVOLVED IN THE PATHOGENIC PROCESS OF CHRONIC PAIN, THE SPECIFIC MECHANISM OF THESE ALTERED TRANSCRIPTIONAL PROFILE STILL REMAINS UNCLEAR. RECENT STUDIES HAVE SHOWN THAT EPIGENETIC MECHANISMS, INCLUDING DNA/RNA METHYLATION, HISTONE MODIFICATION AND CIRCULAR RNAS REGULATION, ARE INVOLVED IN THE OCCURRENCE AND DEVELOPMENT OF CHRONIC PAIN. IN THIS REVIEW, WE PROVIDE A DESCRIPTION OF RESEARCH ON THE ROLE OF EPIGENETIC MECHANISM IN CHRONIC PAIN, SUMMARIZE THE LATEST CLINICAL AND PRECLINICAL ADVANCE IN THIS FIELD, AND PROPOSE THE POTENTIAL DIRECTIONS FOR FURTHER RESEARCH TO ELUCIDATE THE MOLECULAR MECHANISM UNDERLYING THE PATHOGENESIS OF CHRONIC PAIN. 2022 11 6828 25 [GLOBAL UNDERSTANDING OF PAIN]. CLINICALLY, IT IS WELL-KNOWN THAT CHRONIC PAIN INDUCES DEPRESSION, ANXIETY, AND REDUCED QUALITY OF LIFE. NEUROPATHIC PAIN, WHICH IS CHARACTERIZED BY SPONTANEOUS BURNING PAIN, HYPERALGESIA AND ALLODYNIA, IS THE MOST DIFFICULT PAIN TO MANAGE IN THE PAIN CLINIC. HOWEVER, THE COMPLICATED PATHOPHYSIOLOGY OF NEUROPATHIC PAIN IS NOT YET UNDERSTOOD. A BETTER UNDERSTANDING OF ITS PATHOPHYSIOLOGY HAS GIVEN US MORE INSIGHT INTO ITS VARIOUS MECHANISMS AND POSSIBLE TREATMENT OPTIONS. THIS REVIEW WILL EXPLORE THE MOST CURRENT ISSUES IN THE FIELD OF PAIN, WITH A FOCUS ON TRANSCRIPTIONAL RESEARCH, EPIGENETIC RESEARCH AND POST-TRANSCRIPTIONAL RESEARCH. FOR A GLOBAL UNDERSTANDING OF THE PAIN, IT IS NECESSARY TO ANALYZE THE CORRELATION BETWEEN THESE TEMPORAL PARAMETERS AND PHENOMICS. 2012 12 3108 21 GENOMICS OF PAIN IN OSTEOARTHRITIS. OSTEOARTHRITIS (OA) ACCOUNTS FOR THE MAJORITY OF THE DISEASE BURDEN FOR MUSCULOSKELETAL DISORDERS AND IS ONE OF THE LEADING CAUSES OF DISABILITY WORLDWIDE. THIS DISABILITY IS THE RESULT NOT OF THE CARTILAGE LOSS THAT DEFINES OA RADIOGRAPHICALLY, BUT OF THE CHRONIC PAIN WHOSE PRESENCE DEFINES SYMPTOMATIC OA. IT IS BECOMING CLEAR THAT MANY GENES, EACH WITH A SMALL EFFECT SIZE, CONTRIBUTE TO THE RISK OF DEVELOPING OA. HOWEVER, THE GENETICS OF OA PAIN ARE ONLY JUST STARTING TO BE EXPLORED. THIS REVIEW WILL DESCRIBE THE FIRST GENES TO HAVE BEEN IDENTIFIED IN GENOMIC STUDIES OF OA PAIN, AS WELL AS THE POSSIBLE DUAL ROLES OF GENES PREVIOUSLY IDENTIFIED IN GENOMIC STUDIES OF OA IN THE CONTEXT OF PAIN. DIFFICULTIES ASSOCIATED WITH ATTEMPTING TO CHARACTERISE THE GENETICS OF OA PAIN WILL BE DISCUSSED AND PROMISING FUTURE AVENUES OF RESEARCH INTO GENETIC AND EPIGENETIC FACTORS AFFECTING OA PAIN DESCRIBED. 2013 13 5028 24 PERSONALIZING PEDIATRIC PAIN MEDICINE: USING POPULATION-SPECIFIC PHARMACOGENETICS, GENOMICS, AND OTHER -OMICS APPROACHES TO PREDICT RESPONSE. PERSONALIZED MEDICINE IS THE SCIENCE OF INDIVIDUALIZED PREVENTION AND THERAPY. THE NOTION THAT "ONE SIZE FITS ALL" HAS BEEN REPLACED BY THE IDEA OF PATIENT-TAILORED HEALTH CARE. WITHIN THIS PARADIGM, THE RESEARCH COMMUNITY HAS TURNED TO EXAMINE GENETIC PREDICTORS OF DISEASE AND TREATMENT RESPONSES. PAIN RESEARCHERS HAVE PRODUCED GENETIC STUDIES OVER THE LAST DECADE THAT EVALUATE THE ASSOCIATION OF GENETIC VARIABILITY WITH PAIN SENSITIVITY AND ANALGESIC RESPONSE. WHILE MOST OF THESE STUDIES HAVE BEEN CONDUCTED AMONG COHORTS OF SUBJECTS OF EUROPEAN DESCENT, SOME HAVE INCLUDED OTHER RACIAL AND ETHNIC GROUPS, PROVIDING EVIDENCE OF VARIABLE RESPONSES TO ANALGESICS. SIMULTANEOUSLY, THERE IS AN INCREASED RECOGNITION REGARDING THE COMPLEXITY OF PAIN RESEARCH, ACKNOWLEDGING THE ADDITIONAL ROLE OF EPIGENETIC, TRANSCRIPTOMIC, PROTEOMIC, AND METABOLOMIC FACTORS IN THE DEVELOPMENT, EXPERIENCE, AND TREATMENT OF PAIN. THIS ARTICLE PROVIDES AN INTRODUCTION TO POPULATION-SPECIFIC PHARMACOGENETICS, PROTEOMICS AND OTHER "-OMICS" TECHNOLOGIES TO PREDICT DRUG RESPONSE TO PAIN MEDICATIONS IN CHILDREN. IT AIMS TO PROVIDE ANESTHESIOLOGISTS WITH THE BASIC KNOWLEDGE TO UNDERSTAND THE POTENTIAL IMPLICATIONS OF GENETIC AND EPIGENETIC FACTORS MANAGING THE PAIN OF PEDIATRIC PATIENTS. 2015 14 1248 19 CURRENT EVIDENCE FOR BIOLOGICAL BIOMARKERS AND MECHANISMS UNDERLYING ACUTE TO CHRONIC PAIN TRANSITION ACROSS THE PEDIATRIC AGE SPECTRUM. CHRONIC PAIN IS HIGHLY PREVALENT IN THE PEDIATRIC POPULATION. MANY FACTORS ARE INVOLVED IN THE TRANSITION FROM ACUTE TO CHRONIC PAIN. CURRENTLY, THERE ARE CONCEPTUAL MODELS PROPOSED, BUT THEY LACK A MECHANISTICALLY SOUND INTEGRATED THEORY CONSIDERING THE STAGES OF CHILD DEVELOPMENT. OBJECTIVE BIOMARKERS ARE CRITICALLY NEEDED FOR THE DIAGNOSIS, RISK STRATIFICATION, AND PROGNOSIS OF THE PATHOLOGICAL STAGES OF PAIN CHRONIFICATION. IN THIS ARTICLE, WE SUMMARIZE THE CURRENT EVIDENCE ON MECHANISMS AND BIOMARKERS OF ACUTE TO CHRONIC PAIN TRANSITIONS IN INFANTS AND CHILDREN THROUGH THE DEVELOPMENTAL LENS. THE GOAL IS TO IDENTIFY GAPS AND OUTLINE FUTURE DIRECTIONS FOR BASIC AND CLINICAL RESEARCH TOWARD A DEVELOPMENTALLY INFORMED THEORY OF PAIN CHRONIFICATION IN THE PEDIATRIC POPULATION. AT THE OUTSET, THE IMPORTANCE OF OBJECTIVE BIOMARKERS FOR CHRONIFICATION OF PAIN IN CHILDREN IS OUTLINED, FOLLOWED BY A SUMMARY OF THE CURRENT EVIDENCE ON THE MECHANISMS OF ACUTE TO CHRONIC PAIN TRANSITION IN ADULTS, IN ORDER TO CONTRAST WITH THE DEVELOPMENTAL MECHANISMS OF PAIN CHRONIFICATION IN THE PEDIATRIC POPULATION. EVIDENCE IS PRESENTED TO SHOW THAT CHRONIC PAIN MAY HAVE ITS ORIGIN FROM INSULTS EARLY IN LIFE, WHICH PRIME THE CHILD FOR THE DEVELOPMENT OF CHRONIC PAIN IN LATER LIFE. FURTHERMORE, AVAILABLE GENETIC, EPIGENETIC, PSYCHOPHYSICAL, ELECTROPHYSIOLOGICAL, NEUROIMAGING, NEUROIMMUNE, AND SEX MECHANISMS ARE DESCRIBED IN INFANTS AND OLDER CHILDREN. IN CONCLUSION, FUTURE DIRECTIONS ARE DISCUSSED WITH A FOCUS ON RESEARCH GAPS, TRANSLATIONAL AND CLINICAL IMPLICATIONS. UTILIZATION OF DEVELOPMENTAL MECHANISMS FRAMEWORK TO INFORM CLINICAL DECISION-MAKING AND STRATEGIES FOR PREVENTION AND MANAGEMENT OF ACUTE TO CHRONIC PAIN TRANSITIONS IN CHILDREN, IS HIGHLIGHTED. 2023 15 2932 24 GENES AND EPIGENETIC PROCESSES AS PROSPECTIVE PAIN TARGETS. CHRONIC PAIN AFFECTS APPROXIMATELY ONE IN FIVE ADULTS, RESULTING IN A GREATLY REDUCED QUALITY OF LIFE AND A HIGHER RISK OF DEVELOPING CO-MORBIDITIES SUCH AS DEPRESSION. AVAILABLE TREATMENTS OFTEN PROVIDE INADEQUATE PAIN RELIEF, BUT IT IS HOPED THAT THROUGH DEEPER UNDERSTANDING OF THE MOLECULAR MECHANISMS UNDERLYING CHRONIC PAIN STATES WE CAN DISCOVER NEW AND IMPROVED THERAPIES. ALTHOUGH GENETIC RESEARCH HAS FLOURISHED OVER THE PAST DECADE AND HAS IDENTIFIED MANY KEY GENES IN PAIN PROCESSING, THE BUDDING FIELD OF EPIGENETICS PROMISES TO PROVIDE NEW INSIGHTS AND A MORE DYNAMIC VIEW OF PAIN REGULATION. THIS REVIEW GIVES AN OVERVIEW OF BASIC MECHANISMS AND CURRENT THERAPIES TO TREAT PAIN, AND DISCUSSES THE CLINICAL AND PRECLINICAL EVIDENCE FOR THE CONTRIBUTION OF GENETIC AND EPIGENETIC FACTORS, WITH A FOCUS ON HOW THIS KNOWLEDGE CAN AFFECT DRUG DEVELOPMENT. 2013 16 1160 16 CONTINUING WAR ON PAIN: A PERSONALIZED APPROACH TO THE THERAPY WITH NONSTEROIDAL ANTI-INFLAMMATORY DRUGS AND OPIOIDS. SUCCESSFUL PAIN MANAGEMENT REQUIRES THE DELIVERY OF ANALGESIA WITH MINIMAL RISK OF ADVERSE DRUG REACTIONS. NONSTEROIDAL ANTI-INFLAMMATORY DRUGS AND OPIOIDS REMAIN THE MAINSTAY OF TREATMENT FOR THE MAJORITY OF PATIENTS. UNFORTUNATELY, ALMOST 50% OF ALL PATIENTS EXPERIENCE INADEQUATE PAIN RELIEF AND SERIOUS SIDE EFFECTS. ALLELIC VARIANTS IN GENES CODING FOR TARGET PROTEINS, TRANSPORTERS AND ENZYMES, WHICH GOVERN ANALGESIC DRUGS ACTION AND THEIR FATE IN THE ORGANISM, MIGHT EXPLAIN INTER-INDIVIDUAL VARIABILITY IN PAIN SEVERITY AND IN DRUG-INDUCED PAIN RELIEF AND TOXICITIES. ADDITIONALLY, IT SEEMS THAT EPIGENETIC CHANGES CONTRIBUTE TO THE HIGHLY VARIABLE RESPONSE TO PAIN TREATMENT. THEREFORE, PHARMACOGENOMIC TESTING MIGHT BE A VALUABLE TOOL FOR PERSONALIZATION OF PAIN TREATMENT, WITH A MULTIDISCIPLINARY TEAM APPROACH INVOLVED. 2019 17 2586 19 EPIGENETICS OF PAIN MEDIATORS. PURPOSE OF REVIEW: THE FIELD OF EPIGENETICS CONTINUES ITS INFLUENTIAL RISE AS A MEANS TO BETTER UNDERSTAND AN ORGANISM'S UNIQUE DEVELOPMENTAL IDENTITY OVER A LIFESPAN. WHEREAS A GENOME IS CONSTANT AND UNCHANGING, AN EPIGENOME IS DYNAMIC AND ALTERABLE. EPIGENETIC CHANGES ARE IN RESPONSE TO INNUMERABLE INTERNAL AND EXTERNAL INFLUENCES INCLUDING ENVIRONMENTAL CHANGES SUCH AS DIET, EXERCISE, DISEASE, TOXINS, AND STRESS. EPIGENETICS IS OF PARTICULAR INTEREST IN THE MEDICAL RESEARCH COMMUNITY BOTH FOR THE POTENTIAL TO CAUSE DISEASE AND AS A TARGET FOR THERAPEUTIC INTERVENTIONS. THIS ARTICLE PROVIDES A SUCCINCT EXPLANATION OF THE POTENTIAL FOR EPIGENETICS TO INFLUENCE THE UNDERSTANDING OF PAIN AS WELL AS A REVIEW OF RELEVANT RESEARCH ON THE TOPIC. RECENT FINDINGS: STUDIES ON EPIGENETICS AND PAIN REMAIN LARGELY PRECLINICAL AND INVESTIGATE THE THEORETICAL ABILITY OF EPIGENETICS TO ALTER THE NOCICEPTIVE PATHWAYS BOTH IN THE PERIPHERY AND CENTRALLY. SIGNIFICANT EVIDENCE NOW EXISTS FOR THE ABILITY OF EPIGENETICS TO MODIFY BROADLY CATEGORIZED PAIN TYPES, INCLUDING INFLAMMATORY, NEUROPATHIC, VISCERAL, AND CANCER RELATED. SUMMARY: BOTH PATIENTS AND PROVIDERS RECOGNIZE THAT NOVEL MEDICATIONS FOR THE TREATMENT OF BOTH ACUTE AND CHRONIC PAIN CONDITIONS ARE SORELY NEEDED. THE UNDERSTANDING OF EPIGENETICS AND ITS INFLUENCE ON NOCICEPTION REMAINS IN RELATIVE INFANCY BUT EARLY EVIDENCE IS STRONG FOR POTENTIAL THERAPEUTIC BENEFITS TO TREAT THESE CONDITIONS. 2018 18 789 25 CELLULAR AND MOLECULAR MECHANISMS DRIVING NEUROPATHIC PAIN: RECENT ADVANCEMENTS AND CHALLENGES. CURRENT PHARMACOTHERAPEUTICS FOR NEUROPATHIC PAIN OFFER ONLY SYMPTOMATIC RELIEF WITHOUT TREATING THE UNDERLYING PATHOPHYSIOLOGY. ADDITIONALLY, THEY ARE ASSOCIATED WITH VARIOUS DOSE-LIMITING SIDE EFFECTS. PAIN RESEARCH IN THE PAST FEW DECADES HAS REVOLVED AROUND THE ROLE OF OXIDATIVE-NITROSATIVE STRESS, PROTEIN KINASES, GLIAL CELL ACTIVATION, AND INFLAMMATORY SIGNALING CASCADES BUT HAS FAILED TO PRODUCE SPECIFIC AND EFFECTIVE THERAPIES. AREAS COVERED: THIS REVIEW FOCUSES ON RECENT ADVANCES IN CELLULAR AND MOLECULAR MECHANISMS OF NEUROPATHIC PAIN THAT MAY BE TRANSLATED INTO FUTURE THERAPIES. WE DISCUSS EMERGING TARGETS SUCH AS WNT SIGNALING MECHANISMS, THE TETRAHYDROBIOPTERIN PATHWAY, MRG RECEPTORS, ENDOGENOUS LIPID MEDIATORS, MICRO-RNAS AND THEIR ROLES IN PAIN REGULATION. RECENT EVIDENCE IS ALSO PRESENTED REGARDING GENETIC AND EPIGENETIC MECHANISMS OF PAIN MODULATION. EXPERT OPINION: DURING CHRONIC NEUROPATHIC PAIN, MALADAPTATION OCCURS IN THE PERIPHERAL AND CENTRAL NERVOUS SYSTEMS, INCLUDING A SHIFT IN MICROGLIAL PHENOTYPE FROM A SURVEILLANCE STATE TO AN ACTIVATED STATE. MICROGLIAL ACTIVATION LEADS TO AN ALTERED EXPRESSION OF CELL SURFACE PROTEINS, GROWTH FACTORS, AND INTRACELLULAR SIGNALING MOLECULES THAT CONTRIBUTE TO DEVELOPMENT OF A NEUROINFLAMMATORY CASCADE AND CHRONIC PAIN SENSITIZATION. SPECIFIC TARGETING OF THESE CELLULAR AND MOLECULAR MECHANISMS MAY PROVIDE THE KEY TO DEVELOPMENT OF EFFECTIVE NEUROPATHIC PAIN THERAPIES THAT HAVE MINIMAL SIDE EFFECTS. 2018 19 5042 25 PHARMACOGENOMICS IN PAIN TREATMENT. THE EXPERIENCE OF CHRONIC PAIN IS ONE OF THE COMMONEST REASONS FOR SEEKING MEDICAL ATTENTION, BEING A MAJOR ISSUE IN CLINICAL PRACTICE. WHILE PAIN IS A UNIVERSAL EXPERIENCE, ONLY A SMALL PROPORTION OF PEOPLE WHO FELT PAIN DEVELOP PAIN SYNDROMES. IN ADDITION, PAINKILLERS ARE ASSOCIATED WITH WIDE INTER-INDIVIDUAL VARIABILITY IN THE ANALGESIC RESPONSE. THIS MAY BE PARTLY EXPLAINED BY THE PRESENCE OF SINGLE NUCLEOTIDE POLYMORPHISMS IN GENES ENCODING MOLECULAR ENTITIES INVOLVED IN PHARMACODYNAMICS AND PHARMACOKINETICS. HOWEVER, UPTAKE OF THIS INFORMATION HAS BEEN SLOW DUE IN LARGE PART TO THE LACK OF ROBUST EVIDENCES DEMONSTRATING CLINICAL UTILITY. FURTHERMORE, NOVEL THERAPIES, INCLUDING TARGETING OF EPIGENETIC CHANGES AND GENE THERAPY-BASED APPROACHES ARE FURTHER BROADENING FUTURE OPTIONS FOR THE TREATMENT OF CHRONIC PAIN. THE AIM OF THIS ARTICLE IS TO REVIEW THE EVIDENCES BEHIND PHARMACOGENETICS (PGX) TO INDIVIDUALIZE THERAPY (BOOSTING THE EFFICACY AND MINIMIZING POTENTIAL TOXICITY) AND GENES IMPLICATED IN PAIN MEDICINE, IN TWO PARTS: (I) GENETIC VARIABILITY WITH PAIN SENSITIVITY AND ANALGESIC RESPONSE; AND (II) PHARMACOLOGICAL CONCEPTS APPLIED ON PGX. 2016 20 4852 26 OPPORTUNITIES AND CHALLENGES IN DRUG DEVELOPMENT FOR PEDIATRIC CANCERS. THE USE OF TARGETED SMALL-MOLECULE THERAPEUTICS AND IMMUNOTHERAPEUTICS HAS BEEN LIMITED TO DATE IN PEDIATRIC ONCOLOGY. RECENTLY, THE NUMBER OF PEDIATRIC APPROVALS HAS RISEN, AND REGULATORY INITIATIVES IN THE UNITED STATES AND EUROPE HAVE AIMED TO INCREASE THE STUDY OF NOVEL ANTICANCER THERAPIES IN CHILDREN. CHALLENGES OF DRUG DEVELOPMENT IN CHILDREN INCLUDE THE RARITY OF INDIVIDUAL CANCER DIAGNOSES AND THE HIGH PREVALENCE OF DIFFICULT-TO-DRUG TARGETS, INCLUDING TRANSCRIPTION FACTORS AND EPIGENETIC REGULATORS. ONGOING PEDIATRIC ADAPTATION OF BIOMARKER-DRIVEN TRIAL DESIGNS AND FURTHER EXPLORATION OF AGENTS TARGETING NON-KINASE DRIVERS CONSTITUTE HIGH-PRIORITY OBJECTIVES FOR FUTURE PEDIATRIC ONCOLOGY DRUG DEVELOPMENT. SIGNIFICANCE: INCREASING ATTENTION TO DRUG DEVELOPMENT FOR CHILDREN WITH CANCER BY REGULATORS AND PHARMACEUTICAL COMPANIES HOLDS THE PROMISE OF ACCELERATING THE AVAILABILITY OF NEW THERAPIES FOR CHILDREN WITH CANCER, POTENTIALLY IMPROVING SURVIVAL AND DECREASING THE ACUTE AND CHRONIC TOXICITIES OF THERAPY. HOWEVER, UNIQUE APPROACHES ARE NECESSARY TO STUDY NOVEL THERAPIES IN CHILDREN THAT TAKE INTO ACCOUNT LOW PATIENT NUMBERS, THE PEDIATRIC CANCER GENOMIC LANDSCAPE AND TUMOR MICROENVIRONMENT, AND THE NEED FOR PEDIATRIC FORMULATIONS. IT IS ALSO CRITICAL TO EVALUATE THE POTENTIAL FOR UNIQUE TOXICITIES IN GROWING HOSTS WITHOUT AFFECTING THE PACE OF DISCOVERY FOR CHILDREN WITH THESE LIFE-THREATENING DISEASES. 2021