1 635 274 BIOLOGICAL FUNCTION OF LONG NON-CODING RNA (LNCRNA) XIST. LONG NON-CODING RNAS (LNCRNAS) REGULATE GENE EXPRESSION IN A VARIETY OF WAYS AT EPIGENETIC, CHROMATIN REMODELING, TRANSCRIPTIONAL, AND TRANSLATIONAL LEVELS. ACCUMULATING EVIDENCE SUGGESTS THAT LNCRNA X-INACTIVE SPECIFIC TRANSCRIPT (LNCRNA XIST) SERVES AS AN IMPORTANT REGULATOR OF CELL GROWTH AND DEVELOPMENT. DESPITES ITS ORIGINAL ROLES IN X-CHROMOSOME DOSAGE COMPENSATION, LNCRNA XIST ALSO PARTICIPATES IN THE DEVELOPMENT OF TUMOR AND OTHER HUMAN DISEASES BY FUNCTIONING AS A COMPETING ENDOGENOUS RNA (CERNA). IN THIS REVIEW, WE COMPREHENSIVELY SUMMARIZED RECENT PROGRESS IN UNDERSTANDING THE CELLULAR FUNCTIONS OF LNCRNA XIST IN MAMMALIAN CELLS AND DISCUSSED CURRENT KNOWLEDGE REGARDING THE CERNA NETWORK OF LNCRNA XIST IN VARIOUS DISEASES. LONG NON-CODING RNAS (LNCRNAS) ARE TRANSCRIPTS THAT ARE MORE THAN 200 NT IN LENGTH AND WITHOUT AN APPARENT PROTEIN-CODING CAPACITY (FURLAN AND ROUGEULLE, 2016; MADURO ET AL., 2016). THESE RNAS ARE BELIEVED TO BE TRANSCRIBED BY THE APPROXIMATELY 98-99% NON-CODING REGIONS OF THE HUMAN GENOME (DERRIEN ET AL., 2012; FU, 2014; MONTALBANO ET AL., 2017; SLACK AND CHINNAIYAN, 2019), AS WELL AS A LARGE VARIETY OF GENOMIC REGIONS, SUCH AS EXONIC, TRONIC, AND INTERGENIC REGIONS. HENCE, LNCRNAS ARE ALSO DIVIDED INTO EIGHT CATEGORIES: INTERGENIC LNCRNAS, INTRONIC LNCRNAS, ENHANCER LNCRNAS, PROMOTER LNCRNAS, NATURAL ANTISENSE/SENSE LNCRNAS, SMALL NUCLEOLAR RNA-ENDED LNCRNAS (SNO-LNCRNAS), BIDIRECTIONAL LNCRNAS, AND NON-POLY(A) LNCRNAS (MA ET AL., 2013; DEVAUX ET AL., 2015; ST LAURENT ET AL., 2015; CHEN, 2016; QUINN AND CHANG, 2016; RICHARD AND EICHHORN, 2018; CONNERTY ET AL., 2020). A RANGE OF EVIDENCE HAS SUGGESTED THAT LNCRNAS FUNCTION AS KEY REGULATORS IN CRUCIAL CELLULAR FUNCTIONS, INCLUDING PROLIFERATION, DIFFERENTIATION, APOPTOSIS, MIGRATION, AND INVASION, BY REGULATING THE EXPRESSION LEVEL OF TARGET GENES VIA EPIGENOMIC, TRANSCRIPTIONAL, OR POST-TRANSCRIPTIONAL APPROACHES (CAO ET AL., 2018). MOREOVER, LNCRNAS DETECTED IN BODY FLUIDS WERE ALSO BELIEVED TO SERVE AS POTENTIAL BIOMARKERS FOR THE DIAGNOSIS, PROGNOSIS, AND MONITORING OF DISEASE PROGRESSION, AND ACT AS NOVEL AND POTENTIAL DRUG TARGETS FOR THERAPEUTIC EXPLOITATION IN HUMAN DISEASE (JIANG W. ET AL., 2018; ZHOU ET AL., 2019A). LONG NON-CODING RNA X-INACTIVE SPECIFIC TRANSCRIPT (LNCRNA XIST) ARE A SET OF 15,000-20,000 NT SEQUENCES LOCALIZED IN THE X CHROMOSOME INACTIVATION CENTER (XIC) OF CHROMOSOME XQ13.2 (BROWN ET AL., 1992; DEBRAND ET AL., 1998; KAY, 1998; LEE ET AL., 2013; DA ROCHA AND HEARD, 2017; YANG Z. ET AL., 2018; BROCKDORFF, 2019). PREVIOUS STUDIES HAVE INDICATED THAT LNCRNA XIST REGULATE X CHROMOSOME INACTIVATION (XCI), RESULTING IN THE INHERITABLE SILENCING OF ONE OF THE X-CHROMOSOMES DURING FEMALE CELL DEVELOPMENT. ALSO, IT SERVES A VITAL REGULATORY FUNCTION IN THE WHOLE SPECTRUM OF HUMAN DISEASE (NOTABLY CANCER) AND CAN BE USED AS A NOVEL DIAGNOSTIC AND PROGNOSTIC BIOMARKER AND AS A POTENTIAL THERAPEUTIC TARGET FOR HUMAN DISEASE IN THE CLINIC (LIU ET AL., 2018B; DENG ET AL., 2019; DINESCU ET AL., 2019; MUTZEL AND SCHULZ, 2020; PATRAT ET AL., 2020; WANG ET AL., 2020A). IN PARTICULAR, LNCRNA XIST HAVE BEEN DEMONSTRATED TO BE INVOLVED IN THE DEVELOPMENT OF MULTIPLE TYPES OF TUMORS INCLUDING BRAIN TUMOR, LEUKEMIA, LUNG CANCER, BREAST CANCER, AND LIVER CANCER, WITH THE PROMINENT EXAMPLES OUTLINED IN TABLE 1. IT WAS ALSO BELIEVED THAT LNCRNA XIST (CHALIGNE AND HEARD, 2014; YANG Z. ET AL., 2018) CONTRIBUTED TO OTHER DISEASES, SUCH AS PULMONARY FIBROSIS, INFLAMMATION, NEUROPATHIC PAIN, CARDIOMYOCYTE HYPERTROPHY, AND OSTEOARTHRITIS CHONDROCYTES, AND MORE SPECIFIC DETAILS CAN BE FOUND IN TABLE 2. THIS REVIEW SUMMARIZES THE CURRENT KNOWLEDGE ON THE REGULATORY MECHANISMS OF LNCRNA XIST ON BOTH CHROMOSOME DOSAGE COMPENSATION AND PATHOGENESIS (ESPECIALLY CANCER) PROCESSES, WITH A FOCUS ON THE REGULATORY NETWORK OF LNCRNA XIST IN HUMAN DISEASE. 2021 2 1728 54 DYSREGULATION OF MICRORNAS IN HYPERTROPHY AND OSSIFICATION OF LIGAMENTUM FLAVUM: NEW ADVANCES, CHALLENGES, AND POTENTIAL DIRECTIONS. PATHOLOGICAL CHANGES IN THE LIGAMENTUM FLAVUM (LF) CAN BE DEFINED AS A PROCESS OF CHRONIC PROGRESSIVE ABERRATIONS IN THE NATURE AND STRUCTURE OF LIGAMENTOUS TISSUES CHARACTERIZED BY INCREASED THICKNESS, REDUCED ELASTICITY, LOCAL CALCIFICATION, OR AGGRAVATED OSSIFICATION, WHICH MAY CAUSE SEVERE MYELOPATHY, RADICULOPATHY, OR BOTH. HYPERTROPHY OF LIGAMENTUM FLAVUM (HLF) AND OSSIFICATION OF LIGAMENTUM FLAVUM (OLF) ARE CLINICALLY COMMON ENTITIES. THOUGH ACCUMULATED EVIDENCE HAS INDICATED BOTH GENETIC AND ENVIRONMENTAL FACTORS COULD CONTRIBUTE TO THE INITIATION AND PROGRESSION OF HLF/OLF, THE DEFINITE PATHOGENESIS REMAINS FULLY UNCLEAR. MICRORNAS (MIRNAS), ONE OF THE IMPORTANT EPIGENETIC MODIFICATIONS, ARE SHORT SINGLE-STRANDED RNA MOLECULES THAT REGULATE PROTEIN-CODING GENE EXPRESSION AT POSTTRANSCRIPTIONAL LEVEL, WHICH CAN DISCLOSE THE MECHANISM UNDERLYING DISEASES, IDENTIFY VALUABLE BIOMARKERS, AND EXPLORE POTENTIAL THERAPEUTIC TARGETS. CONSIDERING THAT MIRNAS PLAY A CENTRAL ROLE IN REGULATING GENE EXPRESSION, WE SUMMARIZED CURRENT STUDIES FROM THE POINT OF VIEW OF MIRNA-RELATED MOLECULAR REGULATION NETWORKS IN HLF/OLF. EXPLORATORY STUDIES REVEALED A VARIETY OF MIRNA EXPRESSION PROFILES AND IDENTIFIED A BATTERY OF UPREGULATED AND DOWNREGULATED MIRNAS IN OLF/HLF PATIENTS THROUGH MICROARRAY DATASETS OR TRANSCRIPTOME SEQUENCING. EXPERIMENTAL STUDIES VALIDATED THE ROLES OF SPECIFIC MIRNAS (E.G., MIR-132-3P, MIR-199B-5P IN OLF, MIR-155, AND MIR-21 IN HLF) IN REGULATING FIBROSIS OR OSTEOGENESIS DIFFERENTIATION OF LF CELLS AND RELATED TARGET GENES OR MOLECULAR SIGNALING PATHWAYS. FINALLY, WE DISCUSSED THE PERSPECTIVES AND CHALLENGES OF MIRNA-BASED MOLECULAR MECHANISM, DIAGNOSTIC BIOMARKERS, AND THERAPEUTIC TARGETS OF HLF/OLF. 2021 3 3198 44 HDAC-LINKED "PROLIFERATIVE" MIRNA EXPRESSION PATTERN IN PANCREATIC NEUROENDOCRINE TUMORS. EPIGENETIC FACTORS ARE ESSENTIALLY INVOLVED IN CARCINOGENESIS, TUMOR PROMOTION, AND CHEMORESISTANCE. TWO EPIGENETIC KEY PLAYERS ARE MIRNAS AND HISTONE DEACETYLASES (HDACS). AS PREVIOUSLY SHOWN BY OWN THEORETICAL DATABANK ANALYSIS, THE CROSSTALK BETWEEN MIRNAS AND HDACS IS RELEVANT IN DIFFERENT HUMAN CHRONIC DISEASES AND CANCEROGENIC PATHWAYS. WE AIMED TO INVESTIGATE A POTENTIAL CONNECTION BETWEEN THE EXPRESSION OF A WELL-DEFINED SUBSET OF "PROLIFERATION-ASSOCIATED" MIRNAS AND THE EXPRESSION OF HDACS AS WELL AS CLINICAL PARAMETERS IN PANCREATIC NEUROENDOCRINE TUMORS (PNETS). MATERIALS AND METHODS: EXPRESSION LEVELS OF MIRNA132-3P, MIRNA145-5P, MIRNA183-5P, MIRNA34A-5P, AND MIRNA449A IN 57 PNETS RESECTED BETWEEN 1997 AND 2015 WERE MEASURED AND LINKED TO THE IMMUNOHISTOCHEMICAL EXPRESSION PATTERN OF MEMBERS OF THE FOUR HDAC CLASSES ON HUMAN TISSUE MICROARRAYS. ALL PNET CASES WERE CLINICALLY AND PATHOLOGICALLY CHARACTERIZED ACCORDING TO PUBLISHED GUIDELINES. CORRELATION ANALYSIS REVEALED A SIGNIFICANT ASSOCIATION BETWEEN EXPRESSION OF SPECIFIC MIRNAS AND TWO MEMBERS OF THE HDAC FAMILY (HDAC3 AND HDAC4). ADDITIONALLY, A LINKAGE BETWEEN MIRNA EXPRESSION AND CLINICO-PATHOLOGICAL PARAMETERS LIKE GRADING, TNM-STAGING, AND HORMONE ACTIVITY WAS FOUND. MOREOVER, OVERALL AND DISEASE-FREE SURVIVAL IS STATISTICALLY CORRELATED WITH THE EXPRESSION OF THE INVESTIGATED MIRNAS. OVERALL, WE DEMONSTRATED THAT SPECIFIC MIRNAS COULD BE LINKED TO HDAC EXPRESSION IN PNETS. ESPECIALLY MIRNA449A (ASSOCIATED WITH HDAC3/4) SEEMS TO PLAY AN IMPORTANT ROLE IN PNET PROLIFERATION AND COULD BE A POTENTIAL PROGNOSTIC FACTOR FOR POOR SURVIVAL. THESE FIRST DATA COULD HELP, TO IMPROVE OUR KNOWLEDGE OF THE COMPLEX INTERACTIONS OF THE EPIGENETIC DRIVERS IN PNETS FOR FURTHER THERAPEUTIC APPROACHES. 2018 4 1861 24 EMERGENCE OF CANCER STEM CELLS IN HEPATOCELLULAR CARCINOMA. LIVER CANCER REPRESENTS THE SECOND MOST DEADLY HUMAN MALIGNANCY. THE MAJOR HISTOLOGICAL SUBTYPE CALLED HEPATOCELLULAR CARCINOMA (HCC) ARISES BY CHRONIC INFLAMMATION-TRIGGERED REGENERATIVE RESPONSES OF NORMALLY QUIESCENT HEPATOCYTES AND PROGENITORS, RESPECTIVELY. SUCH REGENERATIVE STRESS ACCELERATES THE ACCUMULATION OF GENETIC AND EPIGENETIC CHANGES (YAMASHITA & WANG, 2013), WHILE DETAILED MECHANISMS REMAIN UNCERTAIN. IN THIS ISSUE OF THE EMBO JOURNAL, NIKOLAOU ET AL PRESENT A NOVEL HCC MODEL THAT FACILITATES BOTH ISOLATION AND MOLECULAR CHARACTERIZATION OF SELF-RENEWING, HCC-PROPAGATING CANCER STEM CELLS THAT COULD INSTRUCT FUTURE INTERVENTIONS (NIKOLAOU ET AL, 2014). 2015 5 6230 38 THE LONG NONCODING RNA LANDSCAPE IN HYPOXIC AND INFLAMMATORY RENAL EPITHELIAL INJURY. LONG NONCODING RNAS (LNCRNAS) ARE EMERGING AS KEY SPECIES-SPECIFIC REGULATORS OF CELLULAR AND DISEASE PROCESSES. TO IDENTIFY POTENTIAL LNCRNAS RELEVANT TO ACUTE AND CHRONIC RENAL EPITHELIAL INJURY, WE PERFORMED UNBIASED WHOLE TRANSCRIPTOME PROFILING OF HUMAN PROXIMAL TUBULAR EPITHELIAL CELLS (PTECS) IN HYPOXIC AND INFLAMMATORY CONDITIONS. RNA SEQUENCING REVEALED THAT THE PROTEIN-CODING AND NONCODING TRANSCRIPTOMIC LANDSCAPE DIFFERED BETWEEN HYPOXIA-STIMULATED AND CYTOKINE-STIMULATED HUMAN PTECS. HYPOXIA- AND INFLAMMATION-MODULATED LNCRNAS WERE PRIORITIZED FOR FOCUSED FOLLOWUP ACCORDING TO THEIR DEGREE OF INDUCTION BY THESE STRESS STIMULI, THEIR EXPRESSION IN HUMAN KIDNEY TISSUE, AND WHETHER EXPOSURE OF HUMAN PTECS TO PLASMA OF CRITICALLY ILL SEPSIS PATIENTS WITH ACUTE KIDNEY INJURY MODULATED THEIR EXPRESSION. FOR THREE LNCRNAS (MIR210HG, LINC-ATP13A4-8, AND LINC-KIAA1737-2) THAT FULFILLED OUR CRITERIA, WE VALIDATED THEIR EXPRESSION PATTERNS, EXAMINED THEIR LOCI FOR CONSERVATION AND SYNTENY, AND DEFINED THEIR ASSOCIATED EPIGENETIC MARKS. THE LNCRNA LANDSCAPE CHARACTERIZED HERE PROVIDES INSIGHTS INTO NOVEL TRANSCRIPTOMIC VARIATIONS IN THE RENAL EPITHELIAL CELL RESPONSE TO HYPOXIC AND INFLAMMATORY STRESS. 2015 6 6059 42 THE DEVELOPMENT OF A SENSITIVE FLUORESCENT PROTEIN-BASED TRANSCRIPT REPORTER FOR HIGH THROUGHPUT SCREENING OF NEGATIVE MODULATORS OF LNCRNAS. WHILE THE HUMAN GENOME IS PERVASIVELY TRANSCRIBED, <2% OF THE HUMAN GENOME IS TRANSCRIBED INTO PROTEIN-CODING MRNAS, LEAVING MOST OF THE TRANSCRIPTS AS NONCODING RNAS, SUCH AS MICRORNAS AND LONG-NONCODING RNAS (LNCRNAS), WHICH ARE CRITICAL COMPONENTS OF EPIGENETIC REGULATION. LNCRNAS ARE EMERGING AS CRITICAL REGULATORS OF GENE EXPRESSION AND GENOMIC STABILITY. HOWEVER, IT REMAINS LARGELY UNKNOWN ABOUT HOW LNCRNAS ARE REGULATED. HERE, WE DEVELOP A HIGHLY SENSITIVE AND DYNAMIC REPORTER THAT ALLOWS US TO IDENTIFY AND/OR MONITOR NEGATIVE MODULATORS OF LNCRNA TRANSCRIPT LEVELS IN A HIGH THROUGHPUT FASHION. SPECIFICALLY, WE ENGINEER A FLUORESCENT FUSION PROTEIN BY FUSING THREE COPIES OF THE PEST DESTRUCTION DOMAIN OF MOUSE ORNITHINE DECARBOXYLASE (MODC) TO THE C-TERMINAL END OF THE CODON-OPTIMIZED BILIRUBIN-INDUCIBLE FLUORESCENT PROTEIN, DESIGNATED AS DBIFP, AND SHOW THAT THE DBIFP PROTEIN IS HIGHLY DESTABILIZED, COMPARED WITH THE COMMONLY-USED EGFP PROTEIN. WE FURTHER DEMONSTRATE THAT THE DBIFP SIGNAL IS EFFECTIVELY DOWN-REGULATED WHEN THE DBIFP AND MOUSE LNCRNA H19 CHIMERIC TRANSCRIPT IS SILENCED BY MOUSE H19-SPECIFIC SIRNAS. THEREFORE, OUR RESULTS STRONGLY SUGGEST THAT THE DBIFP FUSION PROTEIN MAY SERVE AS A SENSITIVE AND DYNAMIC TRANSCRIPT REPORTER TO MONITOR THE INHIBITION OF LNCRNAS BY MICRORNAS, SYNTHETIC REGULATORY RNA MOLECULES, RNA BINDING PROTEINS, AND/OR SMALL MOLECULE INHIBITORS SO THAT NOVEL AND EFFICACIOUS INHIBITORS TARGETING THE EPIGENETIC CIRCUIT CAN BE DISCOVERED TO TREAT HUMAN DISEASES SUCH AS CANCER AND OTHER CHRONIC DISORDERS. 2018 7 1806 44 EFFECT OF TRANSCRIPTION INHIBITION AND GENERATION OF SUPPRESSIVE VIRAL NON-CODING RNAS. BACKGROUND: HIV-1 PATIENTS RECEIVING COMBINATION ANTIRETROVIRAL THERAPY (CART) SURVIVE INFECTION BUT REQUIRE LIFE-LONG ADHERENCE AT HIGH EXPENSE. IN CHRONIC CART-TREATED PATIENTS WITH UNDETECTABLE VIRAL TITERS, CELL-ASSOCIATED VIRAL RNA IS STILL DETECTABLE, POINTING TO LOW-LEVEL VIRAL TRANSCRIPTIONAL LEAKINESS. TO DATE, THERE ARE NO FDA-APPROVED DRUGS AGAINST HIV-1 TRANSCRIPTION. WE HAVE PREVIOUSLY SHOWN THAT F07#13, A THIRD GENERATION TAT PEPTIDE MIMETIC WITH COMPETITIVE ACTIVITY AGAINST CDK9/T1-TAT BINDING SITES, INHIBITS HIV-1 TRANSCRIPTION IN VITRO AND IN VIVO. RESULTS: HERE, WE DEMONSTRATE THAT INCREASING CONCENTRATIONS OF F07#13 (0.01, 0.1, 1 MICROM) CAUSE A DECREASE IN TAT LEVELS IN A DOSE-DEPENDENT MANNER BY INHIBITING THE CDK9/T1-TAT COMPLEX FORMATION AND SUBSEQUENT UBIQUITIN-MEDIATED TAT SEQUESTRATION AND DEGRADATION. OUR DATA INDICATE THAT COMPLEXES I AND IV CONTAIN DISTINCT PATTERNS OF UBIQUITINATED TAT AND THAT TRANSCRIPTIONAL INHIBITION INDUCED BY F07#13 CAUSES AN OVERALL REDUCTION IN TAT LEVELS. THIS REDUCTION MAY BE TRIGGERED BY F07#13 BUT ULTIMATELY IS MEDIATED BY TAR-GAG VIRAL RNAS THAT BIND SUPPRESSIVE TRANSCRIPTION FACTORS (SIMILAR TO 7SK, NRON, HOTAIR, AND XIST LNCRNAS) TO ENHANCE TRANSCRIPTIONAL GENE SILENCING AND LATENCY. THESE RNAS COMPLEX WITH PRC2, SIN3A, AND CUL4B, RESULTING IN EPIGENETIC MODIFICATIONS. FINALLY, WE OBSERVED AN F07#13-MEDIATED DECREASE OF VIRAL BURDEN BY TARGETING THE R REGION OF THE LONG TERMINAL REPEAT (HIV-1 PROMOTER REGION, LTR), PROMOTING BOTH PAUSED POLYMERASES AND INCREASED EFFICIENCY OF CRISPR/CAS9 EDITING IN INFECTED CELLS. THIS IMPLIES THAT GENE EDITING MAY BE BEST PERFORMED UNDER A REPRESSED TRANSCRIPTIONAL STATE. CONCLUSIONS: COLLECTIVELY, OUR RESULTS INDICATE THAT F07#13, WHICH CAN TERMINATE RNA POLYMERASE II AT DISTINCT SITES, CAN GENERATE SCAFFOLD RNAS, WHICH MAY ASSEMBLE INTO SPECIFIC SETS OF "RNA MACHINES" THAT CONTRIBUTE TO GENE REGULATION. IT REMAINS TO BE SEEN WHETHER THESE EFFECTS CAN ALSO BE SEEN IN VARIOUS CLADES THAT HAVE VARYING PROMOTER STRENGTH, MUTANT LTRS, AND IN PATIENT SAMPLES. 2019 8 5433 32 REL/NF-KAPPA B/I KAPPA B SIGNAL TRANSDUCTION IN THE GENERATION AND TREATMENT OF HUMAN CANCER. THE REL/NF-KAPPA B FAMILY IS A GROUP OF STRUCTURALLY-RELATED, TIGHTLY-REGULATED TRANSCRIPTION FACTORS THAT CONTROL THE EXPRESSION OF A MULTITUDE OF GENES INVOLVED IN KEY CELLULAR AND ORGANISMAL PROCESSES. THE REL/NF-KAPPA B SIGNAL TRANSDUCTION PATHWAY IS MISREGULATED IN A VARIETY OF HUMAN CANCERS, ESPECIALLY ONES OF LYMPHOID CELL ORIGIN, DUE EITHER TO GENETIC CHANGES (SUCH AS CHROMOSOMAL REARRANGEMENTS, AMPLIFICATIONS, AND MUTATIONS) OR TO CHRONIC ACTIVATION OF THE PATHWAY BY EPIGENETIC MECHANISMS. CONSTITUTIVE ACTIVATION OF THE REL/NF-KAPPA B PATHWAY CAN CONTRIBUTE TO THE ONCOGENIC STATE IN SEVERAL WAYS, FOR EXAMPLE, BY DRIVING PROLIFERATION, BY ENHANCING CELL SURVIVAL, OR BY PROMOTING ANGIOGENESIS OR METASTASIS. IN MANY CASES, INHIBITION OF REL/NF-KAPPA B ACTIVITY REVERSES ALL OR PART OF THE MALIGNANT STATE. THUS, THE REL/NF-KAPPA B PATHWAY HAS RECEIVED MUCH ATTENTION AS A FOCAL POINT FOR CLINICAL INTERVENTION. 2002 9 6351 51 THE ROLE OF EPIGENOMICS IN MAPPING POTENTIAL PRECURSORS FOR FOOT AND ANKLE TENDINOPATHY: A SYSTEMATIC REVIEW. TENDINOPATHY OF THE FOOT AND ANKLE IS A COMMON CLINICAL PROBLEM FOR WHICH THE EXACT ETIOLOGY IS POORLY UNDERSTOOD. THE FIELD OF EPIGENETICS HAS BEEN A RECENT FOCUS OF THIS INVESTIGATION. THE PURPOSE OF THIS ARTICLE WAS TO REVIEW THE GENOMIC ADVANCES IN FOOT AND ANKLE TENDINOPATHY THAT COULD POTENTIALLY BE USED TO STRATIFY DISEASE RISK AND CREATE PREVENTATIVE OR THERAPEUTIC AGENTS. A MULTI-DATABASE SEARCH OF PUBMED, COCHRANE, GOOGLE SCHOLAR, AND CLINICALTRIALS.GOV FROM JANUARY 1, 2000 TO JULY 1, 2022 WAS PERFORMED. A TOTAL OF 18 ARTICLES MET INCLUSION AND EXCLUSION CRITERIA FOR THIS REVIEW. THE MAJORITY OF SUCH RESEARCH UTILIZED CASE-CONTROL CANDIDATE GENE ASSOCIATION TO IDENTIFY DIFFERENT GENETIC RISK FACTORS ASSOCIATED WITH CHRONIC TENDINOPATHY. POLYMORPHISMS IN COLLAGEN GENES COL5A1, COL27A1, AND COL1A1 WERE NOTED AT A SIGNIFICANTLY HIGHER FREQUENCY IN ACHILLES TENDINOPATHY VERSUS CONTROL GROUPS. OTHER ALLELIC VARIATIONS THAT WERE OBSERVED AT AN INCREASED INCIDENCE IN ACHILLES TENDINOPATHY WERE TNC AND CASP8. THE EXTRACELLULAR MATRIX (ECM) DEMONSTRATED MACROSCOPIC CHANGES IN ACHILLES TENDINOPATHY, INCLUDING AN INCREASE IN AGGRECAN AND BIGLYCAN MRNA EXPRESSION, AND INCREASED EXPRESSION OF MULTIPLE MATRIX METALLOPROTEINASES. CYTOKINE EXPRESSION WAS ALSO INFLUENCED IN PATHOLOGY AND ABERRANTLY DEMONSTRATED DYNAMIC RESPONSE TO MECHANICAL LOAD. THE PATHOLOGIC ACCUMULATION OF ECM PROTEINS AND CYTOKINE EXPRESSION ALTERS THE ADAPTIVE RESPONSE NORMAL TENDON HAS TO PHYSIOLOGIC STRESS, FURTHER PROPAGATING THE RISK FOR TENDINOPATHY. BY IDENTIFYING AND UNDERSTANDING THE EPIGENETIC MEDIATORS THAT LEAD TO TENDINOPATHY, THERAPEUTIC AGENTS CAN BE DEVELOPED TO TARGET THE EXACT UNDERLYING ETIOLOGY AND MINIMIZE SIDE EFFECTS.LEVEL OF EVIDENCE: LEVEL IV: SYSTEMATIC REVIEW OF LEVEL II-IV STUDIES. 2023 10 2818 22 FIBROSIS UNDER ARREST. APPROXIMATELY 5% OF PEOPLE THAT ARE HOSPITALIZED FOR ANY REASON DEVELOP ACUTE KIDNEY FAILURE, WHICH, IN SOME CASES, PROGRESSES TO A CHRONIC CONDITION RESULTING IN FIBROSIS OF THE KIDNEY AND PERMANENT CHANGES IN THE ORGAN'S FUNCTION. TWO NEW STUDIES SUGGEST THAT CELL CYCLE ARREST OF EPITHELIAL CELLS AND EPIGENETIC MODIFICATIONS HAVE KEY ROLES IN THE SWITCH TO CHRONIC DISEASE (PAGES 535-543 AND 544-550). 2010 11 1063 54 CLINICAL SIGNIFICANCE OF MICRORNAS IN CHRONIC AND ACUTE HUMAN LEUKEMIA. SMALL NON-CODING MICRORNAS (MIRNAS) ARE EPIGENETIC REGULATORS THAT TARGET SPECIFIC CELLULAR MRNA TO MODULATE GENE EXPRESSION PATTERNS AND CELLULAR SIGNALING PATHWAYS. MIRNAS ARE INVOLVED IN A WIDE RANGE OF BIOLOGICAL PROCESSES AND ARE FREQUENTLY DEREGULATED IN HUMAN CANCERS. NUMEROUS MIRNAS PROMOTE TUMORIGENESIS AND CANCER PROGRESSION BY ENHANCING TUMOR GROWTH, ANGIOGENESIS, INVASION AND IMMUNE EVASION, WHILE OTHERS HAVE TUMOR SUPPRESSIVE EFFECTS (HAYES, ET AL., TRENDS MOL MED 20(8): 460-9, 2014; STAHLHUT AND SLACK, GENOME MED 5 (12): 111, 2013). THE EXPRESSION PROFILE OF CANCER MIRNAS CAN BE USED TO PREDICT PATIENT PROGNOSIS AND CLINICAL RESPONSE TO TREATMENT (BOUCHIE, NAT BIOTECHNOL 31(7): 577, 2013). THE MAJORITY OF MIRNAS ARE INTRACELLULAR LOCALIZED, HOWEVER CIRCULATING MIRNAS HAVE BEEN DETECTED IN VARIOUS BODY FLUIDS AND REPRESENT NEW BIOMARKERS OF SOLID AND HEMATOLOGIC CANCERS (FABRIS AND CALIN, MOL ONCOL 10(3):503-8, 2016; ALLEGRA, ET AL., INT J ONCOL 41(6): 1897-912, 2012). THIS REVIEW DESCRIBES THE CLINICAL RELEVANCE OF MIRNAS, LNCRNAS AND SNORNAS IN THE DIAGNOSIS, PROGNOSIS AND TREATMENT RESPONSE IN PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), CHRONIC MYELOID LEUKEMIA (CML), ACUTE LYMPHOCYTIC LEUKEMIA (ALL), ACUTE MYELOID LEUKEMIA (AML) AND ACUTE ADULT T-CELL LEUKEMIA (ATL). 2016 12 3959 47 LONG NON-CODING RNAS TARGET PATHOGENETICALLY RELEVANT GENES AND PATHWAYS IN RHEUMATOID ARTHRITIS. RHEUMATOID ARTHRITIS (RA) IS A CHRONIC INFLAMMATORY AUTOIMMUNE DISEASE DRIVEN BY GENETIC, ENVIRONMENTAL AND EPIGENETIC FACTORS. LONG NON-CODING RNAS (LNCRNAS) ARE A KEY COMPONENT OF THE EPIGENETIC MECHANISMS AND ARE KNOWN TO BE INVOLVED IN THE DEVELOPMENT OF AUTOIMMUNE DISEASES. IN THIS WORK WE AIMED TO IDENTIFY SIGNIFICANTLY DIFFERENTIALLY EXPRESSED LNCRNAS (DE-LNCRNAS) THAT ARE FUNCTIONALLY CONNECTED TO MODULATED GENES STRICTLY ASSOCIATED WITH RA. IN TOTAL, 542,500 TRANSCRIPTS HAVE BEEN PROFILED IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) FROM FOUR PATIENTS WITH EARLY ONSET RA PRIOR ANY TREATMENT AND FOUR HEALTHY DONORS USING CLARIOM D ARRAYS. RESULTS WERE CONFIRMED BY REAL-TIME PCR IN 20 PATIENTS AND 20 CONTROLS. SIX DE-LNCRNAS TARGET EXPERIMENTALLY VALIDATED MIRNAS ABLE TO REGULATE DIFFERENTIALLY EXPRESSED GENES (DEGS) IN RA; AMONG THEM, ONLY FTX, HNRNPU-AS1 AND RP11-498C9.15 TARGETED A LARGE NUMBER OF DEGS. MOST IMPORTANTLY, RP11-498C9.15 TARGETED THE LARGEST NUMBER OF SIGNALLING PATHWAYS THAT WERE FOUND TO BE ENRICHED BY THE GLOBAL AMOUNT OF RA-DEGS AND THAT HAVE ALREADY BEEN ASSOCIATED WITH RA AND RA-SYNOVIOCYTES. MOREOVER, RP11-498C9.15 TARGETED THE MOST HIGHLY CONNECTED GENES IN THE RA INTERACTOME, THUS SUGGESTING ITS INVOLVEMENT IN CRUCIAL GENE REGULATION. THESE RESULTS INDICATE THAT, BY MODULATING BOTH MICRORNAS AND GENE EXPRESSION, RP11-498C9.15 MAY PLAY A PIVOTAL ROLE IN RA PATHOGENESIS. 2019 13 5153 30 PPP2R2B HYPERMETHYLATION CAUSES ACQUIRED APOPTOSIS DEFICIENCY IN SYSTEMIC AUTOIMMUNE DISEASES. CHRONIC INFLAMMATION CAUSES TARGET ORGAN DAMAGE IN PATIENTS WITH SYSTEMIC AUTOIMMUNE DISEASES. THE FACTORS THAT ALLOW THIS PROTRACTED RESPONSE ARE POORLY UNDERSTOOD. WE ANALYZED THE TRANSCRIPTIONAL REGULATION OF PPP2R2B (B55SS), A MOLECULE NECESSARY FOR THE TERMINATION OF THE IMMUNE RESPONSE, IN PATIENTS WITH AUTOIMMUNE DISEASES. ALTERED EXPRESSION OF B55SS CONDITIONED RESISTANCE TO CYTOKINE WITHDRAWAL-INDUCED DEATH (CWID) IN PATIENTS WITH AUTOIMMUNE DISEASES. THE IMPAIRED UPREGULATION OF B55SS WAS CAUSED BY INFLAMMATION-DRIVEN HYPERMETHYLATION OF SPECIFIC CYTOSINES LOCATED WITHIN A REGULATORY ELEMENT OF PPP2R2B PREVENTING CTCF BINDING. THIS PHENOTYPE COULD BE INDUCED IN HEALTHY T CELLS BY EXPOSURE TO TNF-ALPHA. OUR RESULTS REVEAL A GENE WHOSE EXPRESSION IS AFFECTED BY AN ACQUIRED DEFECT, THROUGH AN EPIGENETIC MECHANISM, IN THE SETTING OF SYSTEMIC AUTOIMMUNITY. BECAUSE FAILURE TO REMOVE ACTIVATED T CELLS THROUGH CWID COULD CONTRIBUTE TO AUTOIMMUNE PATHOLOGY, THIS MECHANISM ILLUSTRATES A VICIOUS CYCLE THROUGH WHICH AUTOIMMUNE INFLAMMATION CONTRIBUTES TO ITS OWN PERPETUATION. 2019 14 3465 58 HYPOTHESIS: REGULATION OF NEUROPLASTICITY MAY INVOLVE I-MOTIF AND G-QUADRUPLEX DNA FORMATION MODULATED BY EPIGENETIC MECHANISMS. RECENT STUDIES DEMONSTRATED THE EXISTENCE IN VIVO OF VARIOUS FUNCTIONAL DNA STRUCTURES THAT DIFFER FROM THE DOUBLE HELIX. THE G-QUADRUPLEX (G4) AND INTERCALATED MOTIF (I-MOTIF OR IM) DNA STRUCTURES ARE FORMED AS KNOTS WHERE, CORRESPONDINGLY, GUANINES OR CYTOSINES ON THE SAME STRAND OF DNA BIND TO EACH OTHER. THERE ARE GROUNDS TO BELIEVE THAT G4 AND IM SEQUENCES PLAY A SIGNIFICANT ROLE IN REGULATING GENE EXPRESSION CONSIDERING THEIR TENDENCY TO BE FOUND IN OR NEAR REGULATORY SITES (SUCH AS PROMOTERS, ENHANCERS, AND TELOMERES) AS WELL AS THE CORRELATION BETWEEN THE PREVALENCE OF G4 OR IM CONFORMATIONS AND SPECIFIC PHASES OF CELL CYCLE. NOTABLY, G4 AND IM CAPABLE SEQUENCES TEND TO BE FOUND ON THE OPPOSITE STRANDS OF THE SAME DNA SITE WITH AT MOST ONE OF THE TWO STRUCTURES FORMED AT ANY GIVEN TIME. THE RECENT EVIDENCE THAT K(+), MG(2+) CONCENTRATIONS DIRECTLY AFFECT IM FORMATION (AND LIKELY G4 FORMATION INDIRECTLY) LEAD US TO BELIEVE THAT THESE STRUCTURES MAY PLAY A MAJOR ROLE IN SYNAPTIC PLASTICITY OF NEURONS, AND, THEREFORE, IN A VARIETY OF CENTRAL NERVOUS SYSTEM (CNS) FUNCTIONS INCLUDING MEMORY, LEARNING, HABITUAL BEHAVIORS, PAIN PERCEPTION AND OTHERS. FURTHERMORE, EPIGENETIC MECHANISMS, WHICH HAVE AN IMPORTANT ROLE IN SYNAPTIC PLASTICITY AND MEMORY FORMATION, WERE ALSO SHOWN TO INFLUENCE FORMATION AND STABILITY OF G4S AND IMS. OUR HYPOTHESIS IS THAT NON-CANONICAL DNA AND RNA STRUCTURES COULD BE AN INTEGRAL PART OF NEUROPLASTICITY CONTROL VIA GENE EXPRESSION REGULATION AT THE LEVEL OF TRANSCRIPTION, TRANSLATION AND SPLICING. WE PROPOSE THAT THE REGULATORY ACTIVITY OF DNA IM AND G4 STRUCTURES IS MODULATED BY DNA METHYLATION/DEMETHYLATION OF THE IM AND/OR G4 SEQUENCES, WHICH FACILITATES THE SWITCH BETWEEN CANONICAL AND NON-CANONICAL CONFORMATION. OTHER NEURONAL MECHANISMS INTERACTING WITH THE FORMATION AND REGULATORY ACTIVITY OF NON-CANONICAL DNA AND RNA STRUCTURES, PARTICULARLY G4, IM AND TRIPLEXES, MAY INVOLVE MICRORNAS AS WELL AS ION AND PROTON FLUXES. WE ARE PROPOSING EXPERIMENTS IN ACUTE BRAIN SLICES AND IN VIVO TO TEST OUR HYPOTHESIS. THE PROPOSED STUDIES WOULD PROVIDE NEW INSIGHTS INTO FUNDAMENTAL NEURONAL MECHANISMS IN HEALTH AND DISEASE AND POTENTIALLY OPEN NEW AVENUES FOR TREATING MENTAL HEALTH DISORDERS. 2019 15 3390 38 HOPX PLAYS A CRITICAL ROLE IN ANTIRETROVIRAL DRUGS INDUCED EPIGENETIC MODIFICATION AND CARDIAC HYPERTROPHY. PEOPLE LIVING WITH HIV (PLWH) HAVE TO TAKE AN ANTIRETROVIRAL THERAPY (ART) FOR LIFE AND SHOW NONCOMMUNICABLE ILLNESSES SUCH AS CHRONIC INFLAMMATION, IMMUNE ACTIVATION, AND MULTIORGAN DYSREGULATION. RECENT STUDIES SUGGEST THAT LONG-TERM USE OF ART INDUCES COMORBID CONDITIONS AND IS ONE OF THE LEADING CAUSES OF HEART FAILURE IN PLWH. HOWEVER, THE MOLECULAR MECHANISM OF ANTIRETROVIRAL DRUGS (ARVS) INDUCED HEART FAILURE IS UNCLEAR. TO DETERMINE THE MECHANISM OF ARVS INDUCED CARDIAC DYSFUNCTION, WE PERFORMED GLOBAL TRANSCRIPTOMIC PROFILING OF ARVS TREATED NEONATAL RAT VENTRICULAR CARDIOMYOCYTES IN CULTURE. DIFFERENTIALLY EXPRESSED GENES WERE IDENTIFIED BY RNA-SEQUENCING. OUR DATA SHOW THAT ARVS TREATMENT CAUSES UPREGULATION OF SEVERAL BIOLOGICAL FUNCTIONS ASSOCIATED WITH CARDIOTOXICITY, HYPERTROPHY, AND HEART FAILURE. GLOBAL GENE EXPRESSION DATA WERE VALIDATED IN CARDIAC TISSUE ISOLATED FROM HIV PATIENTS HAVING A HISTORY OF ART. INTERESTINGLY, WE FOUND THAT HOMEODOMAIN-ONLY PROTEIN HOMEOBOX (HOPX) EXPRESSION WAS SIGNIFICANTLY INCREASED IN CARDIOMYOCYTES TREATED WITH ARVS AND IN THE HEART TISSUE OF HIV PATIENTS. FURTHERMORE, WE FOUND THAT HOPX PLAYS A CRUCIAL ROLE IN ARVS MEDIATED CELLULAR HYPERTROPHY. MECHANISTICALLY, WE FOUND THAT HOPX PLAYS A CRITICAL ROLE IN EPIGENETIC REGULATION, THROUGH DEACETYLATION OF HISTONE, WHILE THE HDAC INHIBITOR, TRICHOSTATIN A, CAN RESTORE THE ACETYLATION LEVEL OF HISTONE 3 IN THE PRESENCE OF ARVS. 2021 16 2568 41 EPIGENETICS OF ALCOHOL-RELATED LIVER DISEASES. ALCOHOL-RELATED LIVER DISEASE (ARLD) IS A PRIMARY CAUSE OF CHRONIC LIVER DISEASE IN THE UNITED STATES. DESPITE ADVANCES IN THE DIAGNOSIS AND MANAGEMENT OF ARLD, IT REMAINS A MAJOR PUBLIC HEALTH PROBLEM ASSOCIATED WITH SIGNIFICANT MORBIDITY AND MORTALITY, EMPHASISING THE NEED TO ADOPT NOVEL APPROACHES TO THE STUDY OF ARLD AND ITS COMPLICATIONS. EPIGENETIC CHANGES ARE INCREASINGLY BEING RECOGNISED AS CONTRIBUTING TO THE PATHOGENESIS OF MULTIPLE DISEASE STATES. HARNESSING THE POWER OF INNOVATIVE TECHNOLOGIES FOR THE STUDY OF EPIGENETICS (E.G., NEXT-GENERATION SEQUENCING, DNA METHYLATION ASSAYS, HISTONE MODIFICATION PROFILING AND COMPUTATIONAL TECHNIQUES LIKE MACHINE LEARNING) HAS RESULTED IN A SEISMIC SHIFT IN OUR UNDERSTANDING OF THE PATHOPHYSIOLOGY OF ARLD. KNOWLEDGE OF THESE TECHNIQUES AND ADVANCES IS OF PARAMOUNT IMPORTANCE FOR THE PRACTICING HEPATOLOGIST AND RESEARCHERS ALIKE. ACCORDINGLY, IN THIS REVIEW ARTICLE WE WILL SUMMARISE THE CURRENT KNOWLEDGE ABOUT ALCOHOL-INDUCED EPIGENETIC ALTERATIONS IN THE CONTEXT OF ARLD, INCLUDING BUT NOT LIMITED TO, DNA HYPER/HYPO METHYLATION, HISTONE MODIFICATIONS, CHANGES IN NON-CODING RNA, 3D CHROMATIN ARCHITECTURE AND ENHANCER-PROMOTER INTERACTIONS. ADDITIONALLY, WE WILL DISCUSS THE STATE-OF-THE-ART TECHNIQUES USED IN THE STUDY OF ARLD (E.G. SINGLE-CELL SEQUENCING). WE WILL ALSO HIGHLIGHT THE EPIGENETIC REGULATION OF CHEMOKINES AND THEIR PROINFLAMMATORY ROLE IN THE CONTEXT OF ARLD. LASTLY, WE WILL EXAMINE THE CLINICAL APPLICATIONS OF EPIGENETICS IN THE DIAGNOSIS AND MANAGEMENT OF ARLD. 2022 17 6584 45 TRIGGERING RECEPTORS EXPRESSED ON MYELOID CELLS 1 : OUR NEW PARTNER IN HUMAN ONCOLOGY? INFLAMMATION IS RECOGNIZED AS ONE OF THE HALLMARKS OF CANCER. INDEED, STRONG EVIDENCE INDICATES THAT CHRONIC INFLAMMATION PLAYS A MAJOR ROLE IN ONCOGENESIS, PROMOTING GENOME INSTABILITY, EPIGENETIC ALTERATIONS, PROLIFERATION AND DISSEMINATION OF CANCER CELLS. MONONUCLEAR PHAGOCYTES (MPS) HAVE BEEN IDENTIFIED AS KEY CONTRIBUTORS OF THE INFLAMMATORY INFILTRATE IN SEVERAL SOLID HUMAN NEOPLASIA, PROMOTING ANGIOGENESIS AND CANCER PROGRESSION. ONE OF THE MOST DESCRIBED AMPLIFIERS OF MPS PRO-INFLAMMATORY INNATE IMMUNE RESPONSE IS THE TRIGGERING RECEPTORS EXPRESSED ON MYELOID CELLS 1 (TREM-1). GROWING EVIDENCE SUGGESTS TREM-1 INVOLVEMENT IN ONCOGENESIS THROUGH CANCER RELATED INFLAMMATION AND THE SURROUNDING TUMOR MICROENVIRONMENT. IN HUMAN ONCOLOGY, HIGH LEVELS OF TREM-1 AND/OR ITS SOLUBLE FORM HAVE BEEN ASSOCIATED WITH POORER SURVIVAL DATA IN SEVERAL SOLID MALIGNANCIES, ESPECIALLY IN HEPATOCELLULAR CARCINOMA AND LUNG CANCER. TREM-1 SHOULD BE CONSIDERED AS A POTENTIAL BIOMARKER IN HUMAN ONCOLOGY AND COULD BE USED AS A NEW THERAPEUTIC TARGET OF INTEREST IN HUMAN ONCOLOGY (TREM-1 INHIBITORS, TREM-1 AGONISTS). MORE CLINICAL STUDIES ARE URGENTLY NEEDED TO CONFIRM TREM-1 (AND TREM FAMILY) ROLES IN THE PROGNOSIS AND THE TREATMENT OF HUMAN SOLID CANCERS. 2022 18 4665 30 NEW INSIGHTS AND ADVANCES IN PATHOGENESIS AND TREATMENT OF VERY EARLY ONSET INFLAMMATORY BOWEL DISEASE. VERY EARLY ONSET INFLAMMATORY BOWEL DISEASE (VEO-IBD) IS CHARACTERIZED BY MULTIFACTORIAL CHRONIC RECURRENT INTESTINAL INFLAMMATION. COMPARED WITH ELDERLY PATIENTS, THOSE WITH VEO-IBD HAVE A MORE SERIOUS CONDITION, NOT RESPONSIVE TO CONVENTIONAL TREATMENTS, WITH A POOR PROGNOSIS. RECENT STUDIES FOUND THAT GENETIC AND IMMUNOLOGIC ABNORMALITIES ARE CLOSELY RELATED TO VEO-IBD. INTESTINAL IMMUNE HOMEOSTASIS MONOGENIC DEFECTS (IIHMDS) ARE CHANGED THROUGH VARIOUS MECHANISMS. RECENT STUDIES HAVE ALSO REVEALED THAT ABNORMALITIES IN GENES AND IMMUNE MOLECULAR MECHANISMS ARE CLOSELY RELATED TO VEO-IBD. IIHMDS CHANGE THROUGH VARIOUS MECHANISMS. EPIGENETIC FACTORS CAN MEDIATE THE INTERACTION BETWEEN THE ENVIRONMENT AND GENOME, AND GENETIC FACTORS AND IMMUNE MOLECULES MAY BE INVOLVED IN THE PATHOGENESIS OF THE ENVIRONMENT AND GUT MICROBIOTA. THESE DISCOVERIES WILL PROVIDE NEW DIRECTIONS AND IDEAS FOR THE TREATMENT OF VEO-IBD. 2022 19 3074 32 GENOME-WIDE DNA METHYLOME AND TRANSCRIPTOME CHANGES INDUCED BY INORGANIC NANOPARTICLES IN HUMAN KIDNEY CELLS AFTER CHRONIC EXPOSURE. THE UNIQUE PHYSICOCHEMICAL PROPERTIES MAKE INORGANIC NANOPARTICLES (INPS) AN EXCITING TOOL IN DIAGNOSIS AND DISEASE MANAGEMENT. HOWEVER, AS INPS ARE RELATIVELY DIFFICULT TO FULLY DEGRADE AND EXCRETE, THEIR UNINTENDED ACCUMULATION IN THE TISSUE MIGHT RESULT IN ADVERSE HEALTH EFFECTS. HEREIN, WE PROVIDE A METHYLOME-TRANSCRIPTOME FRAMEWORK FOR CHRONIC EFFECTS OF INPS, COMMONLY USED IN BIOMEDICAL APPLICATIONS, IN HUMAN KIDNEY TH-1 CELLS. RENAL CLEARANCE IS ONE OF THE MOST IMPORTANT ROUTES OF NANOPARTICLE EXCRETION; THEREFORE, A DETAILED EVALUATION OF NANOPARTICLE-MEDIATED NEPHROTOXICITY IS AN IMPORTANT TASK. INTEGRATED ANALYSIS OF METHYLOME AND TRANSCRIPTOME CHANGES INDUCED BY INPS (PEG-AUNPS, FE(3)O(4)NPS, SIO(2)NPS, AND TIO(2)NPS) REVEALED SIGNIFICANTLY DEREGULATED GENES WITH FUNCTIONAL CLASSIFICATION IN IMMUNE RESPONSE, DNA DAMAGE, AND CANCER-RELATED PATHWAYS. ALTHOUGH MOST DEREGULATED GENES WERE UNIQUE TO INDIVIDUAL INPS, A RELATIVELY HIGH PROPORTION OF THEM ENCODED THE TRANSCRIPTION FACTORS. INTERESTINGLY, FOS HYPERMETHYLATION INVERSELY CORRELATING WITH GENE EXPRESSION WAS ASSOCIATED WITH ALL INPS EXPOSURES. OUR STUDY EMPHASIZES THE NEED FOR A MORE COMPREHENSIVE INVESTIGATION OF INPS' BIOLOGICAL SAFETY, ESPECIALLY AFTER CHRONIC EXPOSURE. 2022 20 6484 31 TOXICOLOGIC PROFILE OF ACRYLONITRILE. ACRYLONITRILE IS A MONOMER USED EXTENSIVELY AS A RAW MATERIAL IN THE MANUFACTURING OF ACRYLIC FIBERS, PLASTICS, SYNTHETIC RUBBERS, AND ACRYLAMIDE. IT HAS BEEN CLASSIFIED AS A PROBABLE HUMAN CARCINOGEN ACCORDING TO THE RESULTS OF NUMEROUS CHRONIC RAT BIOASSAYS. THE PRESENT REPORT SUMMARIZES THE TOXICITY DATA ON ACRYLONITRILE AND REVIEWS AVAILABLE DATA CONCERNING THE MECHANISM (GENETIC VERSUS EPIGENETIC) BY WHICH ACRYLONITRILE IS CARCINOGENIC IN RATS. FROM THE EVALUATION OF THE RELEVANT TOXICITY DATA, IT CAN BE CONCLUDED THAT ACRYLONITRILE IS INDEED CARCINOGENIC TO RATS AFTER EITHER ORAL OR INHALATIONAL EXPOSURE. HOWEVER, INFORMATION ON OTHER MAMMALIAN SPECIES IS LACKING, AND, MOREOVER, THE EXACT MECHANISM OF THE CARCINOGENIC PROCESS IS UNCLEAR. THEREFORE, IT IS RECOMMENDED TO CONDUCT AN ADDITIONAL LONG-TERM INHALATION CARCINOGENICITY STUDY WITH ACRYLONITRILE IN MICE, AS WELL AS STUDIES INTO THE MECHANISM BY WHICH ACRYLONITRILE INDUCES (BRAIN) TUMORS IN RATS (GENETIC VERSUS EPIGENETIC). 1998