1 1432 108 DIFFERENTIAL GENE HYPERMETHYLATION IN GENITAL LICHEN SCLEROSUS AND CANCER: A COMPARATIVE STUDY. AIMS: LICHEN SCLEROSUS (LS) IS A CHRONIC INFLAMMATORY DISEASE OF THE GENITAL SKIN OF UNKNOWN AETIOLOGY. THE ROLE OF LS IN PENILE SQUAMOUS CELL CARCINOGENESIS IS NOT WELL CHARACTERIZED. HPV HAS BEEN IMPLICATED IN BOTH, AS HAVE EPIGENETIC CHANGES. THE PRESENCE OF HPV AND HYPERMETHYLATION OF THE MGMT, P16, RASSF1, RASSF2, TSLC1 AND TSP1 GENES WERE STUDIED IN PENILE LS; MGMT, RASSF2 AND TSLC1 HYPERMETHYLATION IN PENILE CANCER AND TSLC1 HYPERMETHYLATION IN VULVAR LS AND CANCER EXTENDS PREVIOUS RESULTS REPORTED BY OUR GROUP. METHODS AND RESULTS: THIRTY-SEVEN HPV GENOTYPES AND HYPERMETHYLATION WERE EVALUATED BY PCR/REVERSE-LINE-BLOT AND METHYLATION-SPECIFIC PCR RESPECTIVELY, IN 27 PREPUTIAL LS, 24 PENILE SCC, 30 VULVAR SCC, 21 VULVAR LS AND 22 NORMAL SKIN CASES. HPV66 WAS PRESENT IN 3.7% OF PENILE LS CASES, AND P16 AND RASSF2 HYPERMETHYLATION WERE MORE FREQUENT IN PENILE CANCER THAN IN PENILE LS. P16, RASSF1, RASSF2 AND TSP1 HYPERMETHYLATION WERE SIMILAR IN PENILE AND VULVAR LS. CONCLUSIONS: GENE HYPERMETHYLATION IS A COMMON EVENT IN PENILE LS, AND OCCURS APPROXIMATELY AS FREQUENTLY AS IN VULVAR LS. CERTAIN GENES CAN BE HYPERMETHYLATED AS AN EARLY OR LATE EVENT IN LS OR CANCER, RESPECTIVELY. THIS SUGGESTS A POSSIBLE SEQUENTIAL ROLE FOR THESE ALTERATIONS IN THE TRANSITION FROM BENIGN TO MALIGNANT LESIONS. 2013 2 6381 38 THE ROLE OF ONCOGENIC DNA VIRUSES IN PENILE CANCER DEVELOPMENT. PENILE CANCER IS A RELATIVELY RARE NEOPLASIA IN DEVELOPED COUNTRIES, WITH SIGNIFICANT MORBIDITY AND MORTALITY IN DEVELOPING COUNTRIES. PENILE CANCER CAN BE SUBDIVIDED INTO HUMAN PAPILLOMAVIRUS (HPV)-POSITIVE AND HPV-NEGATIVE CASES. WORLDWIDE, THE HPV PREVALENCE IN PENILE CANCER SAMPLES IS AROUND 50%, AND HPV16 IS THE MOST PREVALENT GENOTYPE. ALTHOUGH HPV IS AN IMPORTANT FACTOR FOR CANCER DEVELOPMENT, OTHER ONCOGENIC FACTORS MAY BE ASSOCIATED WITH CARCINOGENESIS. SOME OF THESE FACTORS CAN BE INFECTIOUS, SUCH AS THE EPSTEIN-BARR VIRUS (EBV), AS WELL AS THE MERKEL CELL POLYOMAVIRUS (MCPYV). THE PREVALENCE RATES OF NEARLY 50% FOR BOTH HPV AND EBV INFECTIONS INDICATE AN IMPORTANT ROLE OF THESE VIRUSES IN PENILE TISSUE MALIGNANCY, REINFORCING THE IDEA OF A MULTIFACTORIAL ETIOLOGY OF THE DISEASE. ALTHOUGH THE HPV ROLE IS BETTER UNDERSTOOD, EBV IS THOUGHT TO FACILITATE PERSISTENCE, INTEGRATION, AND MUTATIONS. RECENT STUDIES ON THE MERKEL CELL POLYOMAVIRUS HAVE NOT SHOWN A RELEVANT PREVALENCE IN PENILE CANCER SAMPLES, BUT ITS PRESENCE INDICATES THE OPPORTUNISTIC INFECTIOUS POTENTIAL OF THIS VIRUS. REGARDING HPV-NEGATIVE CASES, THE LITERATURE SUGGESTS A LINK WITH YOUNGER AGE AND EPIGENETIC ALTERATIONS, MAINLY THROUGH THE P16INK4A PATHWAY. RECENTLY, SEVERAL BIOMARKERS THAT MIGHT ACT AS PROGNOSTIC TOOLS (E.G., KI-67, SQUAMOUS CELL CARCINOMA ANTIGEN, AMONG OTHERS) HAVE BEEN PROPOSED, BUT THE RESULTS REMAIN CONTROVERSIAL. IN ADDITION, OTHER RISK FACTORS HAVE ALSO BEEN ASSOCIATED WITH PENILE CARCINOGENESIS, SUCH AS THE PRESENCE OF PHIMOSIS, NONCIRCUMCISION, CHRONIC INFLAMMATION, AND NUMBER OF SEXUAL PARTNERS. FURTHER STUDIES ARE NEEDED TO DEVELOP TOOLS FOR EARLY DETECTION AND EPIDEMIOLOGICAL SURVEILLANCE OF PENILE CANCER. 2019 3 3908 30 LICHEN SCLEROSUS: AN AUTOIMMUNOPATHOGENIC AND GENOMIC ENIGMA WITH EMERGING GENETIC AND IMMUNE TARGETS. LICHEN SCLEROSUS (LS) IS AN INFLAMMATORY DERMATOSIS WITH A PREDILECTION FOR ANOGENITAL SKIN. DEVELOPING LESIONS LEAD TO VULVAR PAIN AND SEXUAL DYSFUNCTION, WITH A SIGNIFICANT LOSS OF STRUCTURAL ANATOMICAL ARCHITECTURE, SCLEROSIS, AND INCREASED RISK OF MALIGNANCY. ONSET MAY OCCUR AT ANY AGE IN BOTH SEXES, BUT TYPICALLY AFFECTS MORE FEMALES THAN MALES, PRESENTING IN A BIMODAL FASHION AMONG PRE-PUBERTAL CHILDREN AND MIDDLE-AGED ADULTS. A DEFINITIVE CURE REMAINS ELUSIVE AS THE EXACT PATHOGENESIS OF LS REMAINS UNKNOWN. A GENERAL REVIEW OF LS, HISTOLOGIC CHALLENGES, ALONG WITH AMOUNTING SUPPORT FOR LS AS AN AUTOIMMUNE DISEASE WITH PREFERENCE FOR A T(H)1 IMMUNE RESPONSE AGAINST A GENETIC BACKGROUND IS SUMMARIZED. IN ADDITION TO THE CLASSICALLY REFERENCED ECM1 (EXTRACELLULAR MATRIX PROTEIN 1), A FOLLOWING DISCUSSION OF OTHER IMMUNE AND GENETIC TARGETS MORE RECENTLY IMPLICATED AS CAUSATIVE OR ACCELERANT AGENTS OF DISEASE, PARTICULARLY MIR-155, DOWNSTREAM TARGETS OF ECM1, GALECTIN-7, P53, AND EPIGENETIC MODIFICATIONS TO CDKN2A, ARE ADDRESSED FROM THE VIEWPOINT OF THEIR INVOLVEMENT IN THREE DIFFERENT, BUT INTERCONNECTED ASPECTS OF LS PATHOLOGY. COLLECTIVELY, THESE EMERGING TARGETS SERVE NOT ONLY AS INHERENTLY POTENTIAL THERAPEUTIC TARGETS FOR TREATMENT, BUT MAY ALSO PROVIDE FURTHER INSIGHT INTO THIS DEBILITATING AND CRYPTIC DISEASE. 2019 4 6488 37 TP53 R72P POLYMORPHISM MODULATES DNA METHYLATION IN HEPATOCELLULAR CARCINOMA. BACKGROUND: HEPATOCELLULAR CARCINOMA (HCC) IS CHARACTERIZED BY WIDESPREAD EPIDEMIOLOGICAL AND MOLECULAR HETEROGENEITY. PREVIOUS WORK SHOWED THAT IN THE WESTERN PART OF NORTH AFRICA, A REGION OF LOW INCIDENCE OF HCC, MUTATIONS ARE SCARCE FOR THIS TUMOR TYPE. AS EPIGENETIC CHANGES ARE CONSIDERED POSSIBLE SURROGATES TO MUTATIONS IN HUMAN CANCERS, WE DECIDED, THUS, TO CHARACTERIZE DNA METHYLATION IN HCC FROM NORTH-AFRICAN PATIENTS. METHODS: A SET OF 11 LOCI WAS INVESTIGATED IN A SERIES OF 45 TUMOR SPECIMENS USING METHYLATION-SPECIFIC AND COMBINED-BISULFITE RESTRICTION ASSAY PCR. RESULTS OBTAINED ON CLINICAL SAMPLES WERE SUBSEQUENTLY VALIDATED IN LIVER CANCER CELL LINES. RESULTS: DNA METHYLATION AT TUMOR SUPPRESSOR LOCI IS SIGNIFICANTLY HIGHER IN SAMPLES DISPLAYING CHROMOSOME INSTABILITY. MORE IMPORTANTLY, DNA METHYLATION WAS SIGNIFICANTLY HIGHER IN ARG/ARG WHEN COMPARED TO PRO/PRO GENOTYPE CARRIERS AT CODON 72 RS1042522 OF TP53 (65% VS 20% METHYLATED LOCI, P = 0.0006), A POLYMORPHISM ALREADY KNOWN TO AFFECT SOMATIC MUTATION RATE IN HUMAN CARCINOMAS. IN VITRO EXPERIMENTS IN CELL LINES INDICATED THAT ENZYMES CONTROLLING DNA METHYLATION WERE DIFFERENTIALLY REGULATED BY CODON 72 ARG OR PRO ISOFORMS OF P53. FURTHERMORE, THE ARG72-CARRYING VERSION OF P53 WAS SHOWN TO RE-METHYLATE DNA MORE RAPIDLY THAN THE PRO-HARBORING ISOFORM. FINALLY, PRO-CARRYING CELL LINES WERE SHOWN TO BE SIGNIFICANTLY MORE RESISTANT TO DECITABINE TREATMENT (TWO-FOLD, P = 0.005). CONCLUSIONS: OUR DATA SUGGEST THAT ARG72PRO POLYMORPHISM IN A WT P53 CONTEXT MAY ACT AS A PRIMARY DRIVER OF EPIGENETIC CHANGES IN HCC. IT SUGGESTS, IN ADDITION, THAT RS1042522 GENOTYPE MAY PREDICT SENSITIVITY TO EPIGENETIC-TARGETED THERAPY. THIS MODEL OF LIVER TUMORIGENESIS THAT ASSOCIATES LOW PENETRANCE GENETIC PREDISPOSITION TO EPIGENETIC CHANGES EMERGES FROM A REGION OF LOW HCC INCIDENCE AND IT MAY, THEREFORE, APPLY ESSENTIALLY TO POPULATION LIVING IN SIMILAR AREAS. SURVEYS ON POPULATIONS SUBMITTED TO HIGHLY MUTAGENIC CONDITIONS AS PERINATALLY-ACQUIRED CHRONIC HEPATITIS B OR AFLATOXIN B1 EXPOSURE REMAINED TO BE CONDUCTED TO VALIDATE OUR OBSERVATIONS AS A GENERAL MODEL. 2015 5 5673 38 SHARED EPIGENETIC ALTERATIONS BETWEEN ORAL CANCER AND PERIODONTITIS: A PRELIMINARY STUDY. INTRODUCTION: WE RECENTLY DEVELOPED A NON-INVASIVE SAMPLING PROCEDURE FOR ORAL SQUAMOUS CELL CARCINOMA (OSCC) DETECTION BASED ON DNA METHYLATION ANALYSIS OF A PANEL OF 13 GENES. ORAL CANCER, AS WELL AS ACUTE AND CHRONIC INFLAMMATORY DISEASES, MAY INFLUENCE THE METHYLATION LEVEL OF SEVERAL GENES IN THE ORAL CAVITY. IN THE PRESENT STUDY, WE EVALUATED THE PRESENCE OF PERIODONTAL DISEASE (PD) AND THE METHYLATION STATUS USING OUR 13-GENE PANEL. METHODS: ORAL BRUSHING SPECIMENS WERE COLLECTED FROM THREE DIFFERENT PATIENT GROUPS: 23 GINGIVAL OSCC PATIENTS, 15 PATIENTS AFFECTED BY PD, AND 15 HEALTHY VOLUNTEERS LACKING EVIDENCE OF PD. DNA METHYLATION ANALYSIS WAS PERFORMED AND EACH SAMPLE WAS DETERMINED TO BE POSITIVE OR NEGATIVE BASED ON A PREDEFINED CUT-OFF VALUE. RESULTS: POSITIVE RESULTS WERE FOUND FOR 23/23 OSCC PATIENTS, 3/15 PD PATIENTS, AND 0/15 SAMPLES FROM HEALTHY VOLUNTEERS. THE GP1BB AND MIR193 GENES IN THE PD GROUP EXHIBITED MEAN METHYLATION LEVELS SIMILAR TO OSCC PATIENTS. ZAP70 SHOWED DIFFERENT METHYLATION LEVELS AMONG THREE GROUPS. CONCLUSION: PRELIMINARY DATA IDENTIFIED SHARED EPIGENETIC ALTERATIONS BETWEEN PD AND OSCC PATIENTS IN TWO INFLAMMATORY GENES (GP1BB AND MIR193). THIS STUDY MAY HELP TO IDENTIFY POTENTIAL LINKS BETWEEN THE TWO DISEASES AND SERVE AS A STARTING POINT FOR THE FUTURE RESEARCH FOCUSED ON PATHOGENESIS. 2023 6 977 33 CHRONIC ORAL EXPOSURE TO INORGANIC ARSENATE INTERFERES WITH METHYLATION STATUS OF P16INK4A AND RASSF1A AND INDUCES LUNG CANCER IN A/J MICE. ALTHOUGH INORGANIC ARSENATE (IAS(V)) OR ARSENITE (IAS(III)) IS CLEARLY A HUMAN CARCINOGEN, IT HAS BEEN DIFFICULT TO PRODUCE TUMORS IN RODENTS. IN THE PRESENT STUDY, WE ORALLY ADMINISTERED IAS(V) TO A/J MICE TO EXAMINE ARSENIC CARCINOGENICITY IN RODENT. A/J MICE (MALE, N = 120) ASSIGNED TO FOUR GROUPS WERE GIVEN DRINKING WATER CONTAINING 0, 1, 10, AND 100 PPM IAS(V) FOR 18 MONTHS. AT THE END OF EXPERIMENT, THE COMPLETE LUNGS WERE REMOVED AND USED FOR EXAMINING HISTOPATHOLOGY AND EXTRACTING RNA AND DNA. EPIGENETIC EFFECTS OF IAS(V) ON DNA METHYLATION PATTERNS OF P16INK4A AND RASSF1A GENES WERE DETERMINED BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION. CHANGES OF P16INK4A AND RASSF1A AT MRNA AND PROTEIN LEVELS WERE EXAMINED BY REVERSE TRANSCRIPTASE-POLYMERASE CHAIN REACTION AND IMMUNOHISTOCHEMISTRY. ARSENIC WAS ACCUMULATED DOSE DEPENDENTLY IN THE LUNG TISSUES OF IAS(V)-EXPOSED MICE. INCREASE IN LUNG TUMOR NUMBER AND LUNG TUMOR SIZE WAS OBSERVED IN IAS(V)-EXPOSED MICE COMPARED TO THE CONTROL. HISTOPATHOLOGICAL EXAMINATION SHOWED THAT THE RATE OF POORLY DIFFERENTIATED LUNG ADENOCARCINOMA WAS MUCH HIGHER IN IAS(V)-EXPOSED MICE THAN IN THE CONTROL. METHYLATION RATES APPEARED TO BE HIGHER IN A DOSE-RELATED TENDENCY IN LUNG TUMORS FROM IAS(V)-EXPOSED MICE COMPARED TO THE CONTROL. LOWER OR LOSS OF P16INK4A AND RASSF1A EXPRESSION WAS FOUND IN LUNG TUMORS FROM IAS(V)-EXPOSED MICE, COMPARED TO THAT IN NONTUMOR LUNG TISSUES FROM BOTH CONTROL AND IAS(V)-EXPOSED MICE, AND THIS REDUCED OR LOST EXPRESSION WAS IN ACCORDANCE WITH HYPERMETHYLATION OF THE GENES. IN CONCLUSION, IAS(V) EXPOSURE INCREASED LUNG TUMOR INCIDENCE AND MULTIPLICITY IN A/J MICE. EPIGENETIC CHANGES OF TUMOR SUPPRESSOR GENES SUCH AS P16INK4A AND RASSF1A ARE INVOLVED IN THE IAS(V)-INDUCED LUNG CARCINOGENESIS. 2006 7 1575 39 DNA METHYLATION PATTERNS OF GENES RELATED TO IMMUNE RESPONSE IN THE DIFFERENT CLINICAL FORMS OF ORAL LICHEN PLANUS. BACKGROUND: THE ORAL LICHEN PLANUS IS A CHRONIC INFLAMMATORY DISEASE. ALTHOUGH ITS AETIOLOGY IS NOT WELL UNDERSTOOD, THE ROLE OF T LYMPHOCYTES IN ITS INFLAMMATORY EVENTS IS RECOGNISED. IDENTIFYING THE EPIGENETIC MECHANISMS INVOLVED IN THE PATHOGENESIS OF THIS IMMUNE-MEDIATED CONDITION IS FUNDAMENTAL FOR UNDERSTANDING THE INFLAMMATORY REACTION THAT OCCURS IN THE DISEASE. THE PURPOSE OF THIS WORK WAS TO EVALUATE THE METHYLATION PATTERN OF 21 IMMUNE RESPONSE-RELATED GENES IN THE DIFFERENT CLINICAL FORMS OF ORAL LICHEN PLANUS. METHODS: A CROSS-SECTIONAL STUDY WAS PERFORMED TO ANALYSE THE DNA METHYLATION PATTERNS IN THREE DISTINCT GROUPS OF ORAL LICHEN PLANUS: (I) RETICULAR/PLAQUE LESIONS; (II) EROSIVE LESIONS; (III) NORMAL ORAL MUCOSA (CONTROL GROUP). AFTER DNA EXTRACTION FROM BIOPSIES, THE SAMPLES WERE SUBMITTED TO DIGESTIONS BY METHYLATION-SENSITIVE AND METHYLATION-DEPENDENT ENZYMES AND DOUBLE DIGESTION. THE RELATIVE PERCENTAGE OF METHYLATED DNA FOR EACH GENE WAS PROVIDED USING REAL-TIME POLYMERASE CHAIN REACTION ARRAYS. RESULTS: HYPERMETHYLATION OF THE STAT5A GENE WAS OBSERVED ONLY IN THE CONTROL GROUP (59.0%). A HIGHER HYPERMETHYLATION OF THE ELANE GENE WAS FOUND IN RETICULAR/PLAQUE LESIONS (72.1%) COMPARED TO THE EROSIVE LESIONS (50.0%). CONCLUSION: OUR RESULTS SHOW VARIATIONS IN THE METHYLATION PROFILE OF IMMUNE RESPONSE-RELATED GENES, ACCORDING TO THE CLINICAL TYPE OF ORAL LICHEN PLANUS AFTER COMPARING WITH THE NORMAL ORAL MUCOSA. FURTHER STUDIES ARE NECESSARY TO VALIDATE THESE FINDINGS USING GENE EXPRESSION ANALYSIS. 2018 8 2637 35 EPIGENOME-WIDE STUDY IDENTIFIES EPIGENETIC OUTLIERS IN NORMAL MUCOSA OF PATIENTS WITH COLORECTAL CANCER. NONGENETIC PREDISPOSITION TO COLORECTAL CANCER CONTINUES TO BE DIFFICULT TO MEASURE PRECISELY, HAMPERING EFFORTS IN TARGETED PREVENTION AND SCREENING. EPIGENETIC CHANGES IN THE NORMAL MUCOSA OF PATIENTS WITH COLORECTAL CANCER CAN SERVE AS A TOOL IN PREDICTING COLORECTAL CANCER OUTCOMES. WE IDENTIFIED EPIGENETIC CHANGES AFFECTING THE NORMAL MUCOSA OF PATIENTS WITH COLORECTAL CANCER. DNA METHYLATION PROFILING ON NORMAL COLON MUCOSA FROM 77 PATIENTS WITH COLORECTAL CANCER AND 68 CONTROLS IDENTIFIED A DISTINCT SUBGROUP OF NORMALLY-APPEARING MUCOSA WITH MARKEDLY DISRUPTED DNA METHYLATION AT A LARGE NUMBER OF CPGS, TERMED AS "OUTLIER METHYLATION PHENOTYPE" (OMP) AND ARE PRESENT IN 15 OF 77 PATIENTS WITH CANCER VERSUS 0 OF 68 CONTROLS (P < 0.001). SIMILAR FINDINGS WERE ALSO SEEN IN PUBLICLY AVAILABLE DATASETS. COMPARISON OF NORMAL COLON MUCOSA TRANSCRIPTION PROFILES OF PATIENTS WITH OMP CANCER WITH THOSE OF PATIENTS WITH NON-OMP CANCER INDICATES GENES WHOSE PROMOTERS ARE HYPERMETHYLATED IN THE OMP PATIENTS ARE ALSO TRANSCRIPTIONALLY DOWNREGULATED, AND THAT MANY OF THE GENES MOST AFFECTED ARE INVOLVED IN INTERACTIONS BETWEEN EPITHELIAL CELLS, THE MUCUS LAYER, AND THE MICROBIOME. ANALYSIS OF 16S RRNA PROFILES SUGGESTS THAT NORMAL COLON MUCOSA OF OMPS ARE ENRICHED IN BACTERIAL GENERA ASSOCIATED WITH COLORECTAL CANCER RISK, ADVANCED TUMOR STAGE, CHRONIC INTESTINAL INFLAMMATION, MALIGNANT TRANSFORMATION, NOSOCOMIAL INFECTIONS, AND KRAS MUTATIONS. IN CONCLUSION, OUR STUDY IDENTIFIES AN EPIGENETICALLY DISTINCT OMP GROUP IN THE NORMAL MUCOSA OF PATIENTS WITH COLORECTAL CANCER THAT IS CHARACTERIZED BY A DISRUPTED METHYLOME, ALTERED GENE EXPRESSION, AND MICROBIAL DYSBIOSIS. PROSPECTIVE STUDIES ARE NEEDED TO DETERMINE WHETHER OMP COULD SERVE AS A BIOMARKER FOR AN ELEVATED EPIGENETIC RISK FOR COLORECTAL CANCER DEVELOPMENT. PREVENTION RELEVANCE: OUR STUDY IDENTIFIES AN EPIGENETICALLY DISTINCT OMP GROUP IN THE NORMAL MUCOSA OF PATIENTS WITH COLORECTAL CANCER THAT IS CHARACTERIZED BY A DISRUPTED METHYLOME, ALTERED GENE EXPRESSION, AND MICROBIAL DYSBIOSIS. IDENTIFICATION OF OMPS IN HEALTHY CONTROLS AND PATIENTS WITH COLORECTAL CANCER WILL LEAD TO PREVENTION AND BETTER PROGNOSIS, RESPECTIVELY. 2022 9 3897 38 LARGE-SCALE ANALYSIS OF THE GENETIC AND EPIGENETIC ALTERATIONS IN HEPATOCELLULAR CARCINOMA FROM SOUTHEAST CHINA. OUR KNOWLEDGE ABOUT MOLECULAR ALTERATIONS DURING HEPATOCARCINOGENESIS IS STILL FRAGMENTARY, DUE TO LACK OF COMPREHENSIVE GENETIC AND EPIGENETIC ANALYSES IN THE SAME SET OF HEPATOCELLULAR CARCINOMAS (HCCS). IN THIS STUDY, WE CONDUCTED A LARGE-SCALE ANALYSIS, INCLUDING MUTATION SCREENING IN 50 GENES AND METHYLATION ASSAYS IN THREE GENES IN 54 PAIRS OF HCCS AND THEIR NEIGHBORING NON-CANCEROUS TISSUES. ALL SAMPLES WERE COLLECTED FROM THE RESIDENTS IN SOUTHEAST CHINA. WE FOUND HBV INFECTION AND CHRONIC HEPATITIS/CIRRHOSIS IN 83.3% AND 98.1% OF THE CASES, RESPECTIVELY. MUTATIONS WERE IDENTIFIED IN 18 OUT OF 54 (33.3%) SAMPLES, WITH P53 ALTERATIONS IN 14 CASES AND BETA-CATENIN MUTATIONS IN FOUR TUMORS. NO MUTATIONS WERE IDENTIFIED IN THE NEIGHBORING TISSUES. INTERESTINGLY, 9 OUT OF 14 (64.3%) TUMORS CARRYING P53 MUTATIONS DISPLAYED SUBSTITUTION OF SERINE BY ARGININE AT CODON 249, A CHARACTERISTIC CHANGE BELIEVED TO BE INDUCED BY AFLATOXIN-B1. FURTHERMORE, P53 MUTATION WAS SIGNIFICANTLY ASSOCIATED WITH SHORTER RECURRENCE-FREE SURVIVAL (P=0.004). THE RESULTS ALSO REVEALED ABERRANT METHYLATION IN TWO OR MORE GENES IN AS HIGH AS 90% OF TUMORS AND 40% OF ADJACENT TISSUES. THE FREQUENCY OF RASSF1A HYPERMETHYLATION WAS MUCH HIGHER THAN THAT OF P16INK4A AND HAI2 IN BOTH HCC AND NEIGHBORING TISSUES, INDICATING THAT DEREGULATION OF RASSF1A MAY PRECEDE THE OTHER TWO GENES. THESE DATA SUGGEST THAT ABERRANT METHYLATION OCCURS BEFORE MUTATION AND IS AN EARLY EVENT IN THE DEVELOPMENT OF THIS SET OF HCC. OUR FINDINGS HIGHLIGHT P53 AS A PROGNOSTIC FACTOR OF HCC AND RASSF1A AS A POTENTIAL TARGET IN PREVENTING MALIGNANT TRANSFORMATION OF HEPATOCYTES. 2008 10 4407 33 MOLECULAR ANALYSIS OF A MULTISTEP LUNG CANCER MODEL INDUCED BY CHRONIC INFLAMMATION REVEALS EPIGENETIC REGULATION OF P16 AND ACTIVATION OF THE DNA DAMAGE RESPONSE PATHWAY. THE MOLECULAR HALLMARKS OF INFLAMMATION-MEDIATED LUNG CARCINOGENESIS HAVE NOT BEEN FULLY CLARIFIED, MAINLY DUE TO THE SCARCITY OF APPROPRIATE ANIMAL MODELS. WE HAVE USED A SILICA-INDUCED MULTISTEP LUNG CARCINOGENESIS MODEL DRIVEN BY CHRONIC INFLAMMATION TO STUDY THE EVOLUTION OF MOLECULAR MARKERS AND GENETIC ALTERATIONS. WE ANALYZED MARKERS OF DNA DAMAGE RESPONSE (DDR), PROLIFERATIVE STRESS, AND TELOMERIC STRESS: GAMMA-H2AX, P16, P53, AND TERT. LUNG CANCER-RELATED EPIGENETIC AND GENETIC ALTERATIONS, INCLUDING PROMOTER HYPERMETHYLATION STATUS OF P16(CDKN2A), APC, CDH13, RASSF1, AND NORE1A, AS WELL AS MUTATIONS OF TP53, EPIDERMAL GROWTH FACTOR RECEPTOR, K-RAS, N-RAS, AND C-H-RAS, HAVE BEEN ALSO STUDIED. OUR RESULTS SHOWED DDR PATHWAY ACTIVATION IN PRENEOPLASTIC LESIONS, IN ASSOCIATION WITH INDUCIBLE NITRIC OXIDE SYNTHASE AND P53 INDUCTION. P16 WAS ALSO INDUCED IN EARLY TUMORIGENIC PROGRESSION AND WAS INACTIVATED IN BRONCHIOLAR DYSPLASIAS AND TUMORS. REMARKABLY, LACK OF MUTATIONS OF RAS AND EPIDERMAL GROWTH FACTOR RECEPTOR, AND A VERY LOW FREQUENCY OF TP53 MUTATIONS SUGGEST THAT THEY ARE NOT REQUIRED FOR TUMORIGENESIS IN THIS MODEL. IN CONTRAST, EPIGENETIC ALTERATIONS IN P16(CDKN2A), CDH13, AND APC, BUT NOT IN RASSF1 AND NORE1A, WERE CLEARLY OBSERVED. THESE DATA SUGGEST THE EXISTENCE OF A SPECIFIC MOLECULAR SIGNATURE OF INFLAMMATION-DRIVEN LUNG CARCINOGENESIS THAT SHARES SOME, BUT NOT ALL, OF THE MOLECULAR LANDMARKS OF CHEMICALLY INDUCED LUNG CANCER. 2007 11 3125 28 GHSR DNA HYPERMETHYLATION IS A COMMON EPIGENETIC ALTERATION OF HIGH DIAGNOSTIC VALUE IN A BROAD SPECTRUM OF CANCERS. IDENTIFICATION OF A SINGLE MOLECULAR TRAIT THAT IS DETERMINANT OF COMMON MALIGNANCIES MAY SERVE AS A POWERFUL DIAGNOSTIC SUPPLEMENT TO CANCER TYPE-SPECIFIC MARKERS. HERE, WE REPORT A DNA METHYLATION MARK THAT IS CHARACTERISTIC OF SEVEN STUDIED MALIGNANCIES, NAMELY CANCERS OF LUNG, BREAST, PROSTATE, PANCREAS, COLORECTUM, GLIOBLASTOMA AND B CELL CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) (N = 137). THIS MARK WAS DEFINED BY SUBSTANTIAL HYPERMETHYLATION AT THE PROMOTER AND FIRST EXON OF GROWTH HORMONE SECRETAGOUGE RECEPTOR (GHSR) THROUGH BISULFITE PYROSEQUENCING. THE DEGREE OF ABERRANT METHYLATION WAS CAPABLE OF ACCURATE DISCRIMINATION BETWEEN CANCER AND CONTROL SAMPLES. THE HIGHEST SENSITIVITY AND SPECIFICITY OF CANCER DETECTION WAS ACHIEVED FOR CANCERS OF PANCREAS, LUNG, BREAST AND CLL YIELDING THE AREA UNDER THE CURVE (AUC) VALUES OF 1.0000, 0.9952, 0.9800 AND 0.9400, RESPECTIVELY. NARROWING TO A SINGLE CPG SITE WITHIN THE GENE'S PROMOTER OR FOUR CONSECUTIVE CPG UNITS OF THE HIGHEST METHYLATION LEVELS WITHIN THE FIRST EXON IMPROVED THE DETECTION POWER. GHSR HYPERMETHYLATION WAS DETECTED ALREADY AT THE EARLY STAGE TUMORS. THE ACCURATE PERFORMANCE OF THIS MARKER WAS FURTHER REPLICATED IN AN INDEPENDENT SET OF PANCREATIC CANCER AND CONTROL SAMPLES (N = 78). THESE FINDINGS SUPPORT THE CANDIDATURE OF GHSR METHYLATION AS A HIGHLY ACCURATE PAN-CANCER MARKER. 2015 12 5277 34 PROMOTER METHYLATION PROFILE IN PRENEOPLASTIC AND NEOPLASTIC GALLBLADDER LESIONS. GALLBLADDER CARCINOMA (GBC) IS A HIGHLY MALIGNANT NEOPLASM AND REPRESENTS THE LEADING CAUSE OF CANCER DEATH IN CHILEAN WOMEN. IN ORDER TO DETERMINE THE POTENTIAL ROLE OF PROMOTER METHYLATION IN GALLBLADDER CARCINOGENESIS, WE INVESTIGATED THE FREQUENCY OF THIS EPIGENETIC MECHANISM BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) IN 35 CHRONIC CHOLECYSTITIS (CC, SEPARATED ACCORDING TO THE PRESENCE OR ABSENCE OF METAPLASIA), 19 EARLY CANCERS (MUCOSA OR MUSCULARIS PROPIA INVASION) AND 48 ADVANCED CARCINOMAS WITH INVASION OF THE GALLBLADDER SUBSEROSA (25 CASES) AND SEROSA (23 CASES). WE EXAMINED 14 GENES AND OBSERVED AN INCREASE OF MULTIGENIC METHYLATION DURING TUMORAL PROGRESSION WHICH WAS NOT SIGNIFICANTLY ASSOCIATED WITH THE PATIENT'S AGE. FOUR GENES (DAPK1, DLC1, TIMP3, AND RARBETA2) DISPLAYED A PROGRESSIVE INCREASE IN THEIR METHYLATION STATUS FROM CC WITHOUT METAPLASIA TO ADVANCED CARCINOMA INVADING THE SEROSA LAYER (P 5 MM IN SIZE WERE INVESTIGATED. FOR COMPARISON, SERA FROM PATIENTS WITH OTHER SKIN TUMORS (NINE BASAL CELL CANCERS, FIVE KAPOSI'S SARCOMA), DIFFERENT METASTASIZED CANCERS (FIVE BREAST CANCERS, FIVE COLON CANCERS), AND SEVERAL CHRONIC INFLAMMATORY DISEASES (N = 12) WERE ALSO ANALYZED. IN ADDITION, WE EXAMINED IF METHYLATION WAS INVOLVED IN SILENCING TRANSCRIPTION OF THESE GENES IN 12 MELANOMA SPECIMENS. SOCS1, SOCS2, RASSF1A, CDKN2A, AND MGMT WERE METHYLATED IN 75, 43, 64, 75, AND 64% OF MELANOMA SAMPLES, RESPECTIVELY. OF THE 41 MELANOMA PATIENTS, 83% HAD ONE HYPERMETHYLATED GENE, WHILE 66, 51, AND 41% HAD TWO, THREE, OR FOUR HYPERMETHYLATED GENES, RESPECTIVELY. ALSO, 20% OF THESE PATIENTS SHOWED HYPERMETHYLATION FOR ALL GENES, WHILE ONLY 17% SHOWED NO METHYLATION. IMPORTANTLY, THE METHYLATION PROFILE OF THE SELECTED GENES FROM MELANOMA PATIENTS WAS DISTINCT FROM THE OTHER ANALYZED TUMORS. TRANSCRIPTION OF SOCS1, SOCS2, CDKN2A, AND RASSF1A GENES WAS SIGNIFICANTLY REDUCED IN FRESH MELANOMA SAMPLES, WHILE MGMT SHOWED A 12-FOLD UPREGULATION AT THE MESSENGER RIBONUCLEIC ACID LEVEL (P < 0.001). OUR FINDINGS SUGGEST THAT EPIGENETIC SILENCING OF THE STUDIED TUMOR SUPPRESSOR GENES IS A COMMON AND PROBABLY IMPORTANT MECHANISM FOR MELANOMA FORMATION. THIS CONVENIENT METHOD USING A SIMPLE BLOOD SAMPLE MAY CONTRIBUTE TO CLASSIFICATION OF MELANOMA AND AWAITS CLINICAL VALIDATION. 2006 16 1342 33 DETECTING ABNORMAL METHYLATION OF TUMOR SUPPRESSOR GENES GSTP1, P16, RIZ1, AND RASSF1A IN HEPATOCELLULAR CARCINOMA AND ITS CLINICAL SIGNIFICANCE. HEPATOCELLULAR CARCINOMA (HCC) HAS A HIGH RATE OF MORTALITY. FURTHER STUDIES INTO EPIGENETIC CHANGES IN HCC, PARTICULARLY THE ABNORMAL METHYLATION OF TUMOR SUPPRESSOR GENES (TSGS), ARE REQUIRED, SINCE THESE CHANGES MAY PROVIDE NOVEL BIOMARKERS FOR EARLY SCREENING AND DIAGNOSIS OF HCC. BY USING METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP), THE PRESENT STUDY DETECTED THE METHYLATION STATUS IN THE PROMOTER REGION OF 4 CANDIDATE TSGS, GSTP1, P16, RIZ1, AND RASSF1A, RESPECTIVELY, IN 35 PAIRED HCC AND TUMOR-ADJACENT LIVER TISSUES IN ADDITION TO 20 NORMAL LIVER TISSUES. THEIR EFFECT ON THE INITIATION AND PROGRESSION OF HCC WAS ALSO INVESTIGATED BY ANALYZING THE CLINICOPATHOLOGICAL DATA. THE RESULTS OF THE PRESENT STUDY REVEALED THAT THE METHYLATION LEVEL OF RIZ1 AND GSTP1 GENES IN HCC WAS SIGNIFICANTLY INCREASED COMPARED WITH THAT IN THE ADJACENT TISSUES (P<0.01) AND THE NORMAL LIVER TISSUES (P<0.01). THE METHYLATION FREQUENCY OF P16 AND RASSF1A GENES WAS NOT SIGNIFICANTLY INCREASED COMPARED WITH THAT OBSERVED IN THE ADJACENT TISSUES (P>0.05) BUT WAS SIGNIFICANTLY INCREASED COMPARED WITH THE NORMAL TISSUES (P<0.01). IN HCC TISSUES, THE METHYLATION FREQUENCY OF THE GSTP1 GENE IN TUMORS WITH CAPSULAR INVASION WAS SIGNIFICANTLY INCREASED COMPARED WITH THAT IN TUMORS WITHOUT CAPSULAR INVASION (P<0.05). THE METHYLATION FREQUENCY OF P16 GENE IN HEPATITIS B SURFACE ANTIGEN (HBSAG)-POSITIVE HCC PATIENTS WAS SIGNIFICANTLY INCREASED COMPARED WITH THAT IN HBSAG-NEGATIVE PATIENTS (P<0.05). THE METHYLATION STATUS OF RIZ1 AND RASSF1A GENES WAS NOT SIGNIFICANTLY CORRELATED WITH THE CLINICOPATHOLOGICAL DATA (P>0.05). PREVIOUS STUDIES HAVE DEMONSTRATED THAT THE METHYLATION STATUS OF RIZ1 AND GSTP1 GENES IS HCC-SPECIFIC, AND THUS MAY BE USED AS A BIOMARKER TO ASSIST THE CLINICAL DIAGNOSIS OF HCC. WHILE THE METHYLATION OF GSTP1 GENE PROMOTER MAY ASSOCIATE WITH THE INVASIVENESS OF HCC, CHRONIC HEPATITIS B VIRUS INFECTION MAY BE THE CAUSE OF METHYLATION-INDUCED P16 INACTIVATION. 2015 17 2037 37 EPIGENETIC CHANGES OF TIMP-3, GSTP-1 AND 14-3-3 SIGMA GENES AS INDICATION OF STATUS OF CHRONIC INFLAMMATION AND CANCER. OBJECTIVES: THIS STUDY AIMED TO COMPARE THE EPIGENETIC CHANGES VIA HYPERMETHYLATION STATUS OF TIMP-3, GSTP-1 AND 14-3-3SIGMA GENES, BETWEEN HEALTHY SUBJECTS AND PATIENTS WITH REVERSIBLE CHRONIC INFLAMMATORY DISEASE, AND BETWEEN HEALTHY SUBJECTS AND PATIENTS WITH IRREVERSIBLE MALIGNANT DISEASE, TO HIGHLIGHT THE GENETIC CHANGES THAT OCCUR IN THE PROGRESSION FROM AN INFLAMMATORY CONDITION TO IRREVERSIBLE GENETIC CHANGES COMMONLY OBSERVED IN CANCER PATIENTS. METHODS: DNA WAS EXTRACTED FROM THE BLOOD OF 680 HEALTHY SUBJECTS, AND TISSUES AND BLOOD OF 110 PATIENTS WITH CHRONIC INFLAMMATION DISEASE OF THE GUMS, AS WELL AS NEOPLASTIC TISSUES OF 108 BREAST CANCER PATIENTS. METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR) FOR TIMP-3, GSTP-1 AND 14-3-3SIGMA WAS PERFORMED, AND HYPERMETHYLATION STATUS WAS ANALYZED AND COMPARED BETWEEN THE 3 GROUPS. RESULTS: THE HYPERMETHYLATION FREQUENCIES OF TIMP-3 AND GSTP-1 OF REVERSIBLE CHRONIC INFLAMMATORY GUM DISEASE AND THE CONTROL GROUP WERE SIMILAR, BUT BOTH WERE SIGNIFICANTLY LOWER THAN THOSE FOR MALIGNANT DISEASE PATIENTS (P<0.0001). THE METHYLATION FREQUENCY OF 14-3-3SIGMA IN CHRONIC INFLAMMATORY GUM DISEASE WAS HIGHER THAN IN THE CANCER AND CONTROL GROUPS (P<0.0001). THE METHYLATION OF CPG ISLANDS IN TIMP-3 AND GSTP-1 IN CHRONIC INFLAMMATION PATIENTS OCCURRED AS FREQUENTLY AS IN THE CONTROL GROUP, BUT LESS FREQUENTLY THAN IN BREAST CANCER PATIENTS. HOWEVER, THE EPIGENETIC SILENCING OF 14-3-3SIGMA OCCURRED MORE FREQUENTLY IN THE CHRONIC INFLAMMATION GROUP THAN IN CANCER PATIENTS AND HEALTHY CONTROLS. CONCLUSIONS: THE EPIGENETIC SILENCING OF 14-3-3SIGMA MIGHT BE ESSENTIAL FOR CHRONIC INFLAMMATORY GUM DISEASE. THE EPIGENETIC CHANGES PRESENTED IN CHRONIC INFLAMMATION PATIENTS MIGHT DEMONSTRATE AN IRREVERSIBLE DESTRUCTION IN THE TISSUES OR ORGANS SIMILAR TO CANCER. 2014 18 6645 30 UP-REGULATION OF DBPA MRNA IN HEPATOCELLULAR CARCINOMA ASSOCIATED WITH METABOLIC SYNDROME. PURPOSE: METABOLIC SYNDROME (MS) IS A GROUP OF RECOGNIZED RISK FACTORS FOR THE DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC) IN PATIENTS WITH CHRONIC LIVER DISEASE. THE AIM OF THIS STUDY WAS TO ANALYZE THE CLINICOPATHOLOGICAL CHARACTERISTICS OF HCC PATIENTS WITH MS AND THE RISK FACTORS FOR RECURRENCE. ALSO, THE AIM WAS TO INVESTIGATE THE COLD SHOCK PROTEIN: DNA-BINDING PROTEIN A (DBPA) EXPRESSION IN HCC PATIENTS WITH MS. METHODS: A TOTAL OF 243 PATIENTS WHO UNDERWENT CURATIVE RESECTIONS FOR HCC WERE CLASSIFIED INTO TWO GROUPS. DBPA EXPRESSION WAS INVESTIGATED IN 66 HCC PATIENTS WITH MS AND IN 30 PATIENTS WITHOUT MS BY USING REAL-TIME RT-PCR. PROMOTER METHYLATION STATUS WAS EXAMINED BY USING MS-PCR. RESULTS: THE INCIDENCE OF METABOLIC FACTORS AFFECT THE HCC SIGNIFICANTLY HIGHER IN NON-B NON-C PATIENTS THAN IN HEPATITIS B VIRUS (HBV) OR HEPATITIS C VIRUS (HCV) PATIENTS (P < 0.001). UNIVARIATE ANALYSIS OF HCC PATIENTS WITH MS RECURRENCE REVEALED ASPARTATE AMINO TRANSFERASE (AST), MULTIPLE TUMORS, LIVER DAMAGE, HEPATIC VEIN INVASION, ADVANCED CANCER STAGES (P < 0.01), ALPHA-FETOPROTEIN (AFP) AND DIABETES MELLITUS TYPE II (P < 0.05) AS RISK FACTORS. MULTIVARIATE ANALYSIS, AST, MULTIPLE TUMORS, AND HEPATIC VEIN INVASION (P < 0.01) WERE IDENTIFIED AS INDEPENDENT FACTORS FOR THE RECURRENCE. DBPA MRNA WAS HIGHER IN PATIENTS WITH MS THAN IN THOSE WITHOUT MS (P = 0.016), AND IT WAS MOSTLY UPREGULATED IN NON-B NON-C HCC PATIENTS WITH MS THAN IN NON-B NON-C HCC PATIENTS WITHOUT HBV OR HCV. ESPECIALLY, IN HCC PATIENTS WITH DIABETES MELLITUS TYPE II, THE MRNA AND PROTEIN LEVELS WERE HIGHLY UPREGULATED. THE DBPA EXPRESSION WAS REGULATED BY PROMOTER METHYLATION STATUS (P < 0.05). CONCLUSIONS: THIS STUDY IDENTIFIES THAT DBPA MAY ACCELERATE THE HEPATOCARCINOGENESIS IN HCC PATIENTS WITH MS VIA INFLAMMATION-INDUCED AND OXIDATIVE STRESS PATHWAYS. THE DEMETHYLATION-RELATED EPIGENETIC ACTIVATION MAY BE ONE OF THE REGULATING FACTORS FOR HCC PATIENTS WITH MS. 2013 19 5349 35 RASSF1A AND DOK1 PROMOTER METHYLATION LEVELS IN HEPATOCELLULAR CARCINOMA, CIRRHOTIC AND NON-CIRRHOTIC LIVER, AND CORRELATION WITH LIVER CANCER IN BRAZILIAN PATIENTS. HEPATOCELLULAR CARCINOMA (HCC) IS THE SECOND MOST COMMON CAUSE OF CANCER MORTALITY WORLDWIDE. MOST CASES OF HCC ARE ASSOCIATED WITH CIRRHOSIS RELATED TO CHRONIC HEPATITIS B VIRUS OR HEPATITIS C VIRUS INFECTIONS. HYPERMETHYLATION OF PROMOTER REGIONS IS THE MAIN EPIGENETIC MECHANISM OF GENE SILENCING AND HAS BEEN INVOLVED IN HCC DEVELOPMENT. THE AIM OF THIS STUDY WAS TO DETERMINE WHETHER ABERRANT METHYLATION OF RASSF1A AND DOK1 GENE PROMOTERS IS ASSOCIATED WITH THE PROGRESSION OF LIVER DISEASE IN BRAZILIAN PATIENTS. METHYLATION LEVELS WERE MEASURED BY PYROSEQUENCING IN 41 (20 HCC, 9 CIRRHOTIC, AND 12 NON-CIRRHOTIC) LIVER TISSUE SAMPLES. MEAN RATES OF METHYLATION IN RASSF1A AND DOK1 WERE 16.2% AND 12.0% IN NON-CIRRHOTIC, 26.1% AND 19.6% IN CIRRHOTIC, AND 59.1% AND 56.0% IN HCC TISSUES, RESPECTIVELY, SHOWING A GRADUAL INCREASE ACCORDING TO THE PROGRESSION OF THE DISEASE, WITH SIGNIFICANTLY HIGHER LEVELS IN TUMOR TISSUES. IN ADDITION, HYPERMETHYLATION OF RASSF1A AND DOK1 WAS FOUND IN THE VAST MAJORITY (88%) OF THE HCC CASES. INTERESTINGLY, DOK1 METHYLATION LEVELS IN HCC SAMPLES WERE SIGNIFICANTLY HIGHER IN THE GROUP OF YOUNGER (<40 YEARS) PATIENTS, AND HIGHER IN MODERATELY DIFFERENTIATED THAN IN POORLY DIFFERENTIATED TUMORS (P < 0.05). OUR RESULTS REINFORCE THE HYPOTHESIS THAT HYPERMETHYLATION OF RASSF1A AND DOK1 CONTRIBUTES TO HEPATOCARCINOGENESIS AND IS ASSOCIATED TO CLINICOPATHOLOGICAL CHARACTERISTICS. RASSF1A AND DOK1 PROMOTER HYPERMETHYLATION MAY BE A VALUABLE BIOMARKER FOR EARLY DIAGNOSIS OF HCC AND A POTENTIAL MOLECULAR TARGET FOR EPIGENETIC-BASED THERAPY. 2016 20 3873 26 K-RAS AND P16(INK4A)ALTERATIONS IN SPUTUM OF NSCLC PATIENTS AND IN HEAVY ASYMPTOMATIC CHRONIC SMOKERS. NSCLC RATES AMONG THE MOST FREQUENT AND LETHAL NEOPLASM WORLD-WIDE AND A SIGNIFICANT DECREASE IN MORBIDITY AND MORTALITY RELIES ONLY UPON EFFECTIVE EARLY DIAGNOSTIC STRATEGIES. WE INVESTIGATED K-RAS MUTATIONS AND P16(INK4A) HYPERMETHYLATION IN TUMOR TISSUE AND SPUTUM OF 50 PATIENTS WITH NSCLC AND CORRELATED THEM WITH SPUTUM CYTOLOGY AND WITH TUMOR STAGING, GRADING AND LOCATION, TO ASCERTAIN, IN SPUTUM, THEIR POTENTIAL DIAGNOSTIC IMPACT. THE SAME GENETIC/EPIGENETIC ABNORMALITIES AND CYTOLOGICAL FEATURES WERE ALSO EVALUATED IN SPUTUM FROM 100 CHRONIC HEAVY SMOKERS. GENETIC ANALYSIS IDENTIFIED MOLECULAR ABNORMALITIES IN 64% TUMORS (14/50 K-RAS MUTATIONS AND 24/50 P16(INK4A) HYPERMETHYLATION) AND IN 48% SPUTUM (11/50 K-RAS MUTATIONS AND 16/50 P16(INK4A) HYPERMETHYLATION). IN TUMORS K-RAS MUTATIONS AND P16(INK4A) HYPERMETHYLATION WERE MOSTLY MUTUALLY EXCLUSIVE, BEING FOUND IN THE SAME PATIENTS IN 3 CASES ONLY. GENETIC ABNORMALITIES IN SPUTUM WERE DETECTED ONLY IN MOLECULAR ABNORMAL TUMORS. MOLECULAR CHANGES IN SPUTUM HAD RATES OF DETECTION SIMILAR TO CYTOLOGY (42%) BUT THE CYTO-MOLECULAR COMBINATION INCREASED THE DIAGNOSTIC YIELD UP TO 60%. INTERESTINGLY, THE RATE OF DETECTION OF GENETIC CHANGES IN SPUTUM OF TUMORS AT EARLY STAGE (T1) WAS NOT SIGNIFICANTLY DIFFERENT FROM THAT OF TUMORS AT MORE ADVANCED STAGE (T2-T4). IN FACT K-RAS POINT MUTATIONS WERE FREQUENTLY RECOGNISED IN TUMORS AT EARLY STAGE WHILE P16(INK4A) INACTIVATION PREVAILED IN TUMORS AT ADVANCED STAGE ( P=0.0063). AS EXPECTED, DIAGNOSTIC CYTOLOGICAL FINDINGS WERE MORE FREQUENTLY FOUND IN TUMORS AT ADVANCED STAGE (P=0.004). NO CORRELATION WAS FOUND BETWEEN TUMOR GRADING AND LOCATION (CENTRAL VERSUS PERIPHERAL) AND MOLECULAR CHANGES. P16(INK4A) HYPERMETHYLATION, BUT NOT K-RAS MUTATIONS, WAS DOCUMENTED IN SPORADIC CASES OF ASYMPTOMATIC HEAVY SMOKERS (4%) WHERE IT WAS UNCOUPLED FROM CYTOLOGICAL ABNORMALITIES. IN CONCLUSION THE CYTO-MOLECULAR DIAGNOSTIC STRATEGY ADOPTED IN THIS STUDY WAS ABLE TO DETECT THE MAJORITY OF TUMORS BUT IN ORDER TO BE PROPOSED AS EFFECTIVE AND EARLY DIAGNOSTIC TOOL, THIS MOLECULAR PANEL NEEDS TO BE TESTED IN PROSPECTIVE STUDIES WITH ADEQUATE FOLLOW-UP. 2004