1 6824 141 [GENETIC ALTERATIONS IN PRENEOPLASTIC AND NEOPLASTIC INJURIES OF THE GALLBLADDER]. THIS ARTICLE AIMS TO REVIEW THE MOST RELEVANT MORPHOLOGICAL AND MOLECULAR ASPECTS INVOLVED IN GALLBLADDER (GB) CANCER. IN CHILE, GALLBLADDER CANCER IS THE MAIN CAUSE OF DEATH DUE TO CANCER, AMONG WOMEN OLDER THAN 40 YEARS. HOWEVER, THERE IS ALMOST NONE INFORMATION ABOUT THE MORPHOLOGICAL CHANGES AND THE GENETIC ALTERATIONS INVOLVED IN THE BEGINNING AND DEVELOPMENT OF THIS NEOPLASIA. TWO CARCINOGENIC WAYS HAVE BEEN DESCRIBED. THE SEQUENCE ADENOMA-CARCINOMA IS ACCEPTED TO BE LESS FREQUENT AND IMPORTANT. THE MOST IMPORTANT IS THE SEQUENCE WHERE A METAPLASIA EVOLVES TO DISPLASIA THAT PROGRESSES TO CARCINOMA IN SITU AND FINALLY IT BECOMES INVASIVE. THIS PROGRESS REQUIRES 10 TO 15 YEARS APPROXIMATELY. DURING THIS TIME, A CONTINUE PROGRESSION OF INJURIES HAVE BEEN DESCRIBED. MOLECULAR RESEARCH STUDIES SHOW GENETIC ANOMALIES IN SOME GENES WHICH ARE TEMPORARY EVENTS IN PRENEOPLASTIC INJURIES OF THE GALLBLADDER. SOME OF THEM EVEN EXIST BEFORE THE FIRST MORPHOLOGICAL CHANGES, WHILE THE EXPRESSION OF TUMOR SUPPRESSOR GENES LIKE P53, ADHESION MOLECULES AND ONCOGENES, AMONG OTHERS, CAN BE RELATED TO LATE GB CARCINOGENESIS. THE K-RAS GENE SEEMS TO PLAY A ROLE IN THIS NEOPLASIA, MAINLY IN THOSE THAT PRESENT AN ABNORMAL BILIOPANCREATIC UNION. THE MICROSATELITAL INSTABILITY HAS BEEN FOUND IN A SMALL SUBSET OF PRENEOPLASTIC AND NEOPLASTIC LESIONS. THE EXISTENCE OF METHYLATION IN THE PROMOTOR GENE AREAS HAS BEEN RELATED TO THE CELLULAR PROLIFERATION, INVASION AND METASTASIS AND ALSO IN CASES OF CHRONIC CHOLECYSTITIS, SUGGESTING THAT THIS EPIGENETIC PHENOMENON REPRESENTS A CRUCIAL EARLY EVENT IN GB CARCINOGENESIS. 2010 2 4733 34 NOVEL BIOMARKERS FOR THE IDENTIFICATION AND TARGETED THERAPY OF GASTRIC CANCER. GASTRIC CANCER DEVELOPMENT FOLLOWS THE PATHOLOGIC PATTERN SUCH THAT CHRONIC INFLAMMATION IN THE GASTRIC MUCOSA PROGRESSIVELY TRANSFORMS NORMAL MUCOSA INTO ATROPHY, INTESTINAL METAPLASIA, ADENOMA/DYSPLASIA AND EVENTUALLY INVASIVE AND METASTATIC TUMORS. THE ACCUMULATION OF MULTIPLE GENETIC AND EPIGENETIC ALTERATIONS LEADS TO THE DYSREGULATION OF ONCOGENES AND TUMOR SUPPRESSORS, WHICH WAS CONSIDERED AS THE DRIVER BEHIND EVENTS DURING THE TUMORIGENESIS. ALMOST ALL GASTRIC CANCERS ARE ADENOCARCINOMAS, WHICH SHARE CONSIDERABLE HETEROGENEITY WITH DISTINCT MORPHOLOGY, PATHOGENESIS AND CLINICAL BEHAVIOR. THEREFORE, IDENTIFYING SUBTYPES OF GASTRIC CANCERS WITH MOLECULAR AND GENETIC FEATURES WILL BE BENEFICIAL FOR THE EARLY IDENTIFICATION AND SELECTION OF NEW EFFECTIVE AGENTS FOR TARGETED TREATMENT. HIGH-THROUGHPUT SEQUENCING TECHNIQUES SUCH AS WHOLE GENOMIC, EPIGENOME AND TRANSCRIPTOME SEQUENCING AND PROTEOMICS PLATFORMS HAVE IDENTIFIED MAJOR GENOMIC CHARACTERISTICS THAT EXHIBIT IDENTIFICATION AND PROGNOSTIC IMPACTS AND DISTINCT RESPONSE PATTERNS. IN THIS ARTICLE, THE AUTHORS AIM TO SUMMARIZE THE INFORMATION REGARDING THE MOST PROMISING MOLECULES THAT MAY HAVE CLINICAL APPLICATION AS NON-INVASIVE BIOMARKERS AND THERAPY TARGETS. 2015 3 5742 25 SMOKING MOLECULAR DAMAGE IN BRONCHIAL EPITHELIUM. OUR UNDERSTANDING OF THE MOLECULAR PATHOLOGY OF LUNG CANCER IS ADVANCING RAPIDLY WITH SEVERAL SPECIFIC GENES AND CHROMOSOMAL REGIONS BEING IDENTIFIED. LUNG CANCER APPEARS TO REQUIRE MANY MUTATIONS IN BOTH DOMINANT AND RECESSIVE ONCOGENES TO POSSESS MALIGNANT PHENOTYPES. SEVERAL GENETIC AND EPIGENETIC CHANGES ARE COMMON TO ALL LUNG CANCER HISTOLOGIC TYPES, WHILE OTHERS APPEAR TO BE CELL TYPE SPECIFIC. HOWEVER, SPECIFIC ROLES OF THE GENES UNDERGOING MUTATIONS AND THE ORDER OF CUMULATIVE MOLECULAR CHANGES THAT LEAD TO THE DEVELOPMENT OF EACH LUNG TUMOR HISTOLOGIC TYPE REMAIN TO BE FULLY ELUCIDATED. RECENT FINDINGS OF MOLECULAR ABNORMALITIES IN NORMAL APPEARING AND PRENEOPLASTIC BRONCHIAL EPITHELIUM FROM PATIENTS WITH LUNG CANCER AND CHRONIC SMOKERS SUGGEST THAT GENETIC CHANGES MAY SERVE AS BIOMARKERS FOR EARLY DIAGNOSIS, RISK ASSESSMENT AND MONITORING RESPONSE TO CHEMOPREVENTION. 2002 4 4474 38 MOLECULAR PATHOGENESIS OF GALLBLADDER CANCER: AN UPDATE. GALLBLADDER CARCINOMA (GBC) IS THE MOST AGGRESSIVE GASTROINTESTINAL MALIGNANCY THROUGHOUT THE WORLD, WITH WIDE GEOGRAPHICAL VARIANCE. IT IS THE SUBTYPE OF BILIARY TRACT MALIGNANCY THAT HAS THE POOREST PROGNOSIS AND LOWER SURVIVAL AMONG ALL BILIARY TRACT MALIGNANCIES. VARIOUS FACTORS ARE ASSOCIATED WITH GBC PATHOGENESIS SUCH AS ENVIRONMENTAL, MICROBIAL, METABOLIC AND MOLECULAR. CHRONIC INFLAMMATION OF GALLBLADDER DUE TO PRESENCE OF GALLSTONE OR MICROBIAL INFECTION (EG. SALMONELLA OR H. PYLORI) RESULTS IN SUSTAINED PRODUCTION OF INFLAMMATORY MEDIATORS IN THE TISSUE MICROENVIRONMENT, WHICH CAN CAUSE GENOMIC CHANGES LINKED TO CARCINOGENESIS. GENETIC ALTERATIONS ARE ONE OF THE MAJOR FACTORS, ASSOCIATED WITH AGGRESSIVENESS AND PROGNOSIS. RESEARCHES HAVE BEEN DONE TO EXPLORE SUITABLE BIOMARKER FOR EARLY DIAGNOSIS AND IDENTIFY ALTERED MOLECULAR PATHWAYS TO DEVELOP APPROPRIATE BIOMARKERS FOR EARLY DIAGNOSIS, THERAPY AND PREDICTING PROGNOSIS. DIFFERENT AGENTS FOR TARGETED THERAPY AGAINST ACTIONABLE MUTATIONS OF MOLECULES LIKE EGFR, VEGF, MTOR, HER2, PDL-1, PD-1, MET, PI3K, N-CADHERIN, VEGFR, MEK1 AND MEK2 ARE BEING TRIED. DESPITE THESE ADVANCEMENTS, THERE IS DISMAL IMPROVEMENT IN THE SURVIVAL OF GBC PATIENTS. GENETIC ABERRATIONS OTHER THAN ACTIONABLE MUTATIONS AND EPIGENETIC MODIFICATION INCLUDING ABERRANT EXPRESSIONS OF MICRO-RNAS, ARE ALSO BEING STUDIED BOTH AS DIAGNOSTIC BIOMARKER AND THERAPEUTIC TARGETS. COMPLEX PATHOGENESIS OF GBC STILL NEEDS TO BE UNFOLDED. IN THIS REVIEW WE FOCUS ON THE MOLECULAR PATHOGENESIS OF GBC ELUCIDATED TILL DATE ALONG WITH FUTURE DIRECTIONS THAT CAN BE EXPLORED TO ACHIEVE BETTER MANAGEMENT OF GBC PATIENTS. 2019 5 2970 43 GENETIC AND EPIGENETIC SIGNATURES IN HUMAN HEPATOCELLULAR CARCINOMA: A SYSTEMATIC REVIEW. HEPATOCELLULAR CARCINOMA (HCC) IS THE THIRD MOST COMMON CAUSE OF CANCER DEATHS WORLDWIDE, AND THE INCIDENCE OF THIS FATAL DISEASE IS STILL ON RISE. THE MAJORITY OF HCCS EMERGE IN THE BACKGROUND OF A CHRONIC LIVER DISEASE, SUCH AS CHRONIC HEPATITIS AND LIVER CIRRHOSIS. THE CURRENT UNDERSTANDING IS THAT MAJORITY OF HCCS EVOLVE AS A CONSEQUENCE OF CHRONIC INFLAMMATION AND DUE TO THE PRESENCE OF INFECTION WITH HEPATITIS VIRUSES. THESE UNDERLYING PATHOGENIC STIMULI SUBSEQUENTLY INDUCE A SPECTRUM OF GENETIC AND EPIGENETIC ALTERATIONS IN SEVERAL CANCER-RELATED GENES, WHICH ARE INVOLVED IN CELL-CYCLE REGULATION, CELL GROWTH AND ADHESION. SUCH WIDESPREAD GENOMIC ALTERATIONS CAUSE DISRUPTION OF NORMAL CELLULAR SIGNALING AND FINALLY LEAD TO THE ACQUISITION OF A MALIGNANT PHENOTYPE IN HCC. IN GENERAL, THE TYPE OF GENE ALTERATIONS, SUCH AS POINT MUTATIONS, DELETION OF CHROMOSOMAL REGIONS AND ABNORMAL METHYLATION OF GENE PROMOTERS DIFFER ACCORDING TO THE INDIVIDUAL TARGETED GENE. IN HCC, INCIDENCE OF GENETIC ALTERATIONS IS RELATIVELY RARE AND IS LIMITED TO A SUBSET OF FEW CANCER-SPECIFIC GENES, SUCH AS THE TUMOR SUPPRESSOR P53, RB GENES AND ONCOGENES SUCH AS THE CTNNB1. IN CONTRAST, EPIGENETIC CHANGES THAT INVOLVE ABERRANT METHYLATION OF GENES AND OTHER POST-TRANSCRIPTIONAL HISTONE MODIFICATIONS OCCUR FAR MORE FREQUENTLY, AND SOME OF THESE EPIGENETIC ALTERATIONS ARE NOW BEING EXPLOITED FOR THE DEVELOPMENT OF MOLECULAR DIAGNOSTIC SIGNATURES FOR HCC. IN ADDITION, RECENT FINDINGS OF UNIQUE MICRORNA EXPRESSION PROFILES ALSO PROVIDE AN EVIDENCE FOR THE EXISTENCE OF NOVEL MECHANISMS FOR GENE EXPRESSION REGULATION IN HCC. IN THIS REVIEW ARTICLE, WE WILL REVIEW THE CURRENT STATE OF KNOWLEDGE ON THE ACTIVATION OF VARIOUS ONCOGENIC PATHWAYS AND THE INACTIVATION OF TUMOR SUPPRESSOR PATHWAYS IN HCC THAT RESULT IN THE DISRUPTION OF CANCER-RELATED GENE FUNCTION. IN ADDITION, WE WILL SPECIFICALLY EMPHASIZE THE CLINICAL IMPLICATION OF SOME OF THESE GENETIC AND EPIGENETIC ALTERATIONS IN THE MANAGEMENT OF HEPATOCARCINOGENESIS. 2011 6 2122 30 EPIGENETIC IMPACT OF INFECTION ON CARCINOGENESIS: MECHANISMS AND APPLICATIONS. VIRAL AND BACTERIAL INFECTIONS ARE INVOLVED IN THE DEVELOPMENT OF HUMAN CANCERS, SUCH AS LIVER, NASOPHARYNGEAL, CERVICAL, HEAD AND NECK, AND GASTRIC CANCERS. ABERRANT DNA METHYLATION IS FREQUENTLY PRESENT IN THESE CANCERS, AND SOME OF THE ABERRANTLY METHYLATED GENES ARE CAUSALLY INVOLVED IN CANCER DEVELOPMENT AND PROGRESSION. NOTABLY, ABERRANT DNA METHYLATION CAN BE PRESENT EVEN IN NON-CANCEROUS OR PRECANCEROUS TISSUES, AND ITS LEVELS CORRELATE WITH THE RISK OF CANCER DEVELOPMENT, PRODUCING A SO-CALLED 'EPIGENETIC FIELD FOR CANCERIZATION'. MECHANISTICALLY, MOST VIRAL OR BACTERIAL INFECTIONS INDUCE DNA METHYLATION INDIRECTLY VIA CHRONIC INFLAMMATION, BUT RECENT STUDIES HAVE INDICATED THAT SOME VIRUSES HAVE DIRECT EFFECTS ON THE EPIGENETIC MACHINERY OF HOST CELLS. FROM A TRANSLATIONAL VIEWPOINT, A RECENT MULTICENTER PROSPECTIVE COHORT STUDY DEMONSTRATED THAT ASSESSMENT OF THE EXTENT OF ALTERATIONS IN DNA METHYLATION IN NON-CANCEROUS TISSUES CAN BE USED TO PREDICT CANCER RISK. FURTHERMORE, SUPPRESSION OF ABERRANT DNA METHYLATION WAS SHOWN TO BE A USEFUL STRATEGY FOR CANCER PREVENTION IN AN ANIMAL MODEL. HERE, WE REVIEW THE INVOLVEMENT OF ABERRANT DNA METHYLATION IN VARIOUS TYPES OF INFECTION-ASSOCIATED CANCERS, ALONG WITH INDIVIDUAL INDUCTION MECHANISMS, AND WE DISCUSS THE APPLICATION OF THESE FINDINGS FOR CANCER PREVENTION, DIAGNOSIS, AND THERAPY. 2016 7 4429 30 MOLECULAR BIOLOGY AS A TOOL FOR THE TREATMENT OF CANCER. CANCER IS A GENETIC DISEASE CHARACTERIZED BY UNCONTROLLED CELL GROWTH AND METASTASIS. CANCER CAN HAVE A NUMBER OF CAUSES, SUCH THE ACTIVATION OF ONCOGENES, THE INACTIVATION OF TUMOR-SUPPRESSING GENES, MUTAGENESIS PROVOKED BY EXTERNAL FACTORS, AND EPIGENETIC MODIFICATIONS. THE DEVELOPMENT OF DIAGNOSTIC TOOLS AND TREATMENTS USING A MOLECULAR BIOLOGICAL APPROACH PERMITS THE USE OF SENSITIVE, LOW-COST, NONINVASIVE TESTS FOR CANCER PATIENTS. BIOMARKERS CAN BE USED TO PROVIDE RAPID, PERSONALIZED ONCOLOGY, IN PARTICULAR THE MOLECULAR DIAGNOSIS OF CHRONIC MYELOID LEUKEMIA, AND GASTRIC, COLON, AND BREAST CANCERS. MOLECULAR TESTS BASED ON DNA METHYLATION CAN ALSO BE USED TO DIRECT TREATMENTS OR EVALUATE THE TOXIC EFFECTS OF CHEMOTHERAPY. THE ADEQUATE DIAGNOSIS, PROGNOSIS, AND PREDICTION OF THE RESPONSE OF CANCER PATIENTS TO TREATMENT ARE ESSENTIAL TO ENSURE THE MOST EFFECTIVE THERAPY, REDUCE THE DAMAGING EFFECTS OF TREATMENT, AND DIRECT THE THERAPY TO SPECIFIC TARGETS, AND IN THIS CONTEXT, MOLECULAR BIOLOGY HAS BECOME INCREASINGLY IMPORTANT IN ONCOLOGY. IN THIS BRIEF REVIEW, WE WILL DEMONSTRATE THE FUNDAMENTAL IMPORTANCE OF MOLECULAR BIOLOGY FOR THE TREATMENT OF THREE TYPES OF CANCER-CHRONIC MYELOID LEUKEMIA, HEREDITARY DIFFUSE GASTRIC CANCER, AND ASTROCYTOMAS (SPORADIC TUMORS OF THE CENTRAL NERVOUS SYSTEM). IN EACH OF THESE THREE MODELS, DISTINCT BIOLOGICAL MECHANISMS ARE INVOLVED IN THE TRANSFORMATION OF THE CELLS, BUT IN ALL CASES, MOLECULAR BIOLOGY IS FUNDAMENTAL TO THE DEVELOPMENT OF PERSONALIZED ANALYSES FOR EACH PATIENT AND EACH TYPE OF NEOPLASIA, AND TO GUARANTEE THE SUCCESS OF THE TREATMENT. 2018 8 4539 29 MULTISTAGE CARCINOGENESIS IN MOUSE SKIN. THE MOUSE SKIN MODEL OF MULTISTAGE CARCINOGENESIS HAS FOR MANY YEARS PROVIDED A CONCEPTUAL FRAMEWORK FOR STUDYING CARCINOGENESIS MECHANISMS AND POTENTIAL MEANS FOR INHIBITING SPECIFIC STAGES OF CARCINOGENESIS. THE PROCESS OF SKIN CARCINOGENESIS INVOLVES THE STEPWISE ACCUMULATION OF GENETIC CHANGE ULTIMATELY LEADING TO MALIGNANCY. INITIATION, THE FIRST STEP IN MULTISTAGE SKIN CARCINOGENESIS INVOLVES CARCINOGEN-INDUCED GENETIC CHANGES. A TARGET GENE IDENTIFIED FOR SOME SKIN TUMOR INITIATORS IS C-HA-RAS. THE SECOND STEP, THE PROMOTION STAGE, INVOLVES PROCESSES WHEREBY INITIATED CELLS UNDERGO SELECTIVE CLONAL EXPANSION TO FORM VISIBLE PREMALIGNANT LESIONS TERMED PAPILLOMAS. THE PROCESS OF TUMOR PROMOTION INVOLVES THE PRODUCTION AND MAINTENANCE OF A SPECIFIC AND CHRONIC HYPERPLASIA CHARACTERIZED BY A SUSTAINED CELLULAR PROLIFERATION OF EPIDERMAL CELLS. THESE CHANGES ARE BELIEVED TO RESULT FROM EPIGENETIC MECHANISMS SUCH AS ACTIVATION OF THE CELLULAR RECEPTOR, PROTEIN KINASE C, BY SOME CLASSES OF TUMOR PROMOTERS. THE PROGRESSION STAGE INVOLVES THE CONVERSION OF PAPILLOMAS TO MALIGNANT TUMORS, SQUAMOUS CELL CARCINOMAS. THE ACCUMULATION OF ADDITIONAL GENETIC CHANGES IN CELLS COMPRISING PAPILLOMAS HAS BEEN CORRELATED WITH TUMOR PROGRESSION, INCLUDING TRISOMIES OF CHROMOSOMES 6 AND 7 AND LOSS OF HETEROZYGOSITY. THE CURRENT REVIEW FOCUSES ON THE MECHANISMS INVOLVED IN MULTISTAGE SKIN CARCINOGENESIS, A SUMMARY OF KNOWN INHIBITORS OF SPECIFIC STAGES AND THEIR PROPOSED MECHANISMS OF ACTION, AND THE RELEVANCE OF THIS MODEL SYSTEM TO HUMAN CANCER. 1992 9 186 30 ACCUMULATION OF GENETIC AND EPIGENETIC ALTERATIONS IN NORMAL CELLS AND CANCER RISK. CANCERS DEVELOP DUE TO THE ACCUMULATION OF GENETIC AND EPIGENETIC ALTERATIONS. GENETIC ALTERATIONS ARE INDUCED BY AGING, MUTAGENIC CHEMICALS, ULTRAVIOLET LIGHT, AND OTHER FACTORS; WHEREAS, EPIGENETIC ALTERATIONS ARE MAINLY BY AGING AND CHRONIC INFLAMMATION. THE ACCUMULATION AND PATTERNS OF ALTERATIONS IN NORMAL CELLS REFLECT OUR PAST EXPOSURE LEVELS AND LIFE HISTORY. MOST ACCUMULATED ALTERATIONS ARE CONSIDERED AS PASSENGERS, BUT THEIR ACCUMULATION IS CORRELATED WITH CANCER DRIVERS. THIS HAS BEEN SHOWN FOR ABERRANT DNA METHYLATION BUT HAS ONLY BEEN SPECULATED FOR GENETIC ALTERATIONS. HOWEVER, RECENT TECHNOLOGICAL ADVANCEMENTS HAVE ENABLED MEASUREMENT OF RARE POINT MUTATIONS, AND STUDIES HAVE SHOWN THAT THEIR ACCUMULATION LEVELS ARE INDEED CORRELATED WITH CANCER RISK. WHEN THE ACCUMULATION LEVELS OF ABERRANT DNA METHYLATION AND POINT MUTATIONS ARE COMBINED, RISK PREDICTION BECOMES EVEN MORE ACCURATE. WHEN HIGH LEVELS OF ALTERATIONS ACCUMULATE, THE TISSUE HAS A HIGH RISK OF DEVELOPING CANCER OR EVEN MULTIPLE CANCERS AND IS CONSIDERED AS A "CANCERIZATION FIELD", WITH OR WITHOUT EXPANSION OF PHYSIOLOGICAL PATCHES OF CLONAL CELLS. IN THIS REVIEW, WE DESCRIBE THE FORMATION OF A CANCERIZATION FIELD AND HOW WE CAN APPLY ITS DETECTION IN PRECISION CANCER RISK DIAGNOSIS. 2019 10 5211 37 PRENEOPLASTIC LESIONS IN HUMAN HEPATOCARCINOGENESIS. THE EARLY STAGES OF HEPATOCARCINOGENESIS IN HUMAN CHRONIC LIVER DISEASES ARE CHARACTERIZED BY THE EMERGENCE OF PRENEOPLASTIC LESIONS OF WHICH SOME WILL EVENTUALLY DEVELOP INTO HEPATOCELLULAR CARCINOMA (HCC). BASIC STUDIES ON THE GENETIC AND EPIGENETIC ALTERATIONS OF THESE PRENEOPLASTIC LESIONS MAY EVENTUALLY LEAD TO NEW THERAPEUTIC STRATEGIES. CLINICOPATHOLOGICAL STUDIES ARE ALSO IMPORTANT IN ORDER TO DETERMINE OPTIMAL MANAGEMENT OF PATIENTS WITH A PRENEOPLASTIC LESION. THIS ARTICLE AIMS TO PROVIDE A COMPREHENSIVE REVIEW OF THE CURRENT CONCEPTS OF PRENEOPLASTIC LESION IN CHRONIC LIVER DISEASES. THE MICROSCOPICAL SMALL-CELL DYSPLASTIC FOCUS IS THE SMALLEST MORPHOLOGICALLY RECOGNIZABLE PRECURSOR LESION OF HCC AND THEREFORE IS A LOGICAL TARGET OF STUDY TO ELUCIDATE THE EARLIEST EVENTS IN HEPATOCARCINOGENESIS. IN CONTRAST, LARGE-CELL DYSPLASIA IS NOT A PRECURSOR LESION, BUT APPEARS TO BE OF CLINICAL VALUE BECAUSE OF ITS GOOD PREDICTIVE VALUE FOR DEVELOPMENT OF HCC. DYSPLASTIC NODULES (DNS) ARE MACROSCOPICALLY RECOGNIZABLE PRECURSOR LESIONS OF HCC AND HIGH-GRADE DNS (HGDNS) HAVE A RISK OF MALIGNANT TRANSFORMATION. DETECTION OF DNS AND CORRECT DIFFERENTIATION FROM SMALL HCC (<2 CM) IS SOMETIMES DIFFICULT, ESPECIALLY WHEN ONLY IMAGING TECHNIQUES ARE USED. ADDITIONAL CLINICOPATHOLOGICAL STUDIES ON IDENTIFICATION AND OPTIMAL TREATMENT OF DNS ARE NECESSARY. MOLECULAR STUDIES ON HGDNS AND SMALL HCCS MAY YIELD MUCH INFORMATION ON THE GENETIC MECHANISMS INVOLVED IN THE TRANSITION FROM SEVERE DYSPLASIA TO EARLY MALIGNANCY. IN CONTRAST, CURRENTLY AVAILABLE DATA INDICATE THAT (LARGE) REGENERATIVE NODULES DO NOT REPRESENT A DISTINCT STEP IN HEPATOCARCINOGENESIS. ANIMAL MODELS WILL BE HELPFUL IN THE FURTHER UNRAVELLING OF HUMAN HCC DEVELOPMENT, PROVIDED THAT STUDIES ARE PERFORMED ON MODELS THAT ARE GOOD REPRESENTATIVES OF HUMAN HEPATOCARCINOGENESIS. WE PROPOSE THREE CRITERIA BY WHICH GOOD MIMICKERS CAN BE IDENTIFIED. 2005 11 4888 36 OXIDATIVE DAMAGE IN THE PROGRESSION OF CHRONIC LIVER DISEASE TO HEPATOCELLULAR CARCINOMA: AN INTRICATE PATHWAY. THE HISTO-PATHOLOGIC AND MOLECULAR MECHANISMS LEADING TO INITIATION AND PROGRESSION OF HEPATOCELLULAR CARCINOMA (HCC) ARE STILL ILL-DEFINED; HOWEVER, THERE IS INCREASING EVIDENCE THAT THE GRADUAL ACCUMULATION OF MUTATIONS, GENETIC AND EPIGENETIC CHANGES WHICH OCCUR IN PRENEOPLASTIC HEPATOCYTES RESULTS IN THE DEVELOPMENT OF DYSPLASTIC FOCI, NODULES, AND FINALLY, OVERT HCC. AS WELL AS MANY OTHER NEOPLASIAS, LIVER CANCER IS CONSIDERED AN "INFLAMMATORY CANCER", ARISING FROM A CONTEXT OF INFLAMMATION, AND CHARACTERIZED BY INFLAMMATION-RELATED MECHANISMS THAT FAVOR TUMOR CELL SURVIVAL, PROLIFERATION, AND INVASION. MOLECULAR MECHANISMS THAT LINK INFLAMMATION AND NEOPLASIA HAVE BEEN WIDELY INVESTIGATED, AND IT HAS BEEN WELL ESTABLISHED THAT INFLAMMATORY CELLS RECRUITED AT THESE SITES WITH ONGOING INFLAMMATORY ACTIVITY RELEASE CHEMOKINES THAT ENHANCE THE PRODUCTION OF REACTIVE OXYGEN SPECIES. THE LATTER, IN TURN, PROBABLY HAVE A MAJOR PATHOGENIC ROLE IN THE CONTINUUM STARTING FROM HEPATITIS FOLLOWED BY CHRONIC INFLAMMATION, AND ULTIMATELY LEADING TO CANCER. THE RELATIONSHIP AMONGST CHRONIC LIVER INJURY, FREE RADICAL PRODUCTION, AND DEVELOPMENT OF HCC IS EXPLORED IN THE PRESENT REVIEW, PARTICULARLY IN THE LIGHT OF THE COMPLEX NETWORK THAT INVOLVES OXIDATIVE DNA DAMAGE, CYTOKINE SYNTHESIS, TELOMERE DYSFUNCTION, AND MICRORNA REGULATION. 2014 12 5291 34 PROSTATE CARCINOGENESIS: INSIGHTS IN RELATION TO EPIGENETICS AND INFLAMMATION. PROSTATE CANCER IS A MULTIFACTORIAL DISEASE THAT MAINLY OCCURS DUE TO THE ACCUMULATION OF SOMATIC, GENETIC, AND EPIGENETIC CHANGES, RESULTING IN THE INACTIVATION OF TUMOR-SUPPRESSOR GENES AND ACTIVATION OF ONCOGENES. MUTATIONS IN GENES, SPECIFICALLY THOSE THAT CONTROL CELL GROWTH AND DIVISION OR THE REPAIR OF DAMAGED DNA, MAKE THE CELLS GROW AND DIVIDE UNCONTROLLABLY TO FORM A TUMOR. THE RISK OF DEVELOPING PROSTATE CANCER DEPENDS UPON THE GENE THAT HAS UNDERGONE THE MUTATION. IDENTIFYING SUCH GENETIC RISK FACTORS FOR PROSTATE CANCER POSES A CHALLENGE FOR THE RESEARCHERS. BESIDES GENETIC MUTATIONS, MANY EPIGENETIC ALTERATIONS, INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS (METHYLATION, ACETYLATION, UBIQUITYLATION, SUMOYLATION, AND PHOSPHORYLATION) NUCLEOSOMAL REMODELING, AND CHROMOSOMAL LOOPING, HAVE SIGNIFICANTLY CONTRIBUTED TO THE ONSET OF PROSTATE CANCER AS WELL AS THE PROGNOSIS, DIAGNOSIS, AND TREATMENT OF PROSTATE CANCER. CHRONIC INFLAMMATION ALSO PLAYS A MAJOR ROLE IN THE ONSET AND PROGRESSION OF HUMAN CANCER, VIA MODIFICATIONS IN THE TUMOR MICROENVIRONMENT BY INITIATING EPITHELIALMESENCHYMAL TRANSITION AND REMODELING THE EXTRACELLULAR MATRIX. IN THIS ARTICLE, THE AUTHORS PRESENT A BRIEF HISTORY OF THE MECHANISMS AND POTENTIAL LINKS BETWEEN THE GENETIC ABERRATIONS, EPIGENETIC CHANGES, INFLAMMATION, AND INFLAMMASOMES THAT ARE KNOWN TO CONTRIBUTE TO THE PROGNOSIS OF PROSTATE CANCER. FURTHERMORE, THE AUTHORS EXAMINE AND DISCUSS THE CLINICAL POTENTIAL OF PROSTATE CARCINOGENESIS IN RELATION TO EPIGENETICS AND INFLAMMATION FOR ITS DIAGNOSIS AND TREATMENT.. 2021 13 4479 34 MOLECULAR PATHOGENESIS OF ORAL SQUAMOUS CELL CARCINOMA: IMPLICATIONS FOR THERAPY. THE DEVELOPMENT OF ORAL SQUAMOUS CELL CARCINOMA (OSCC) IS A MULTISTEP PROCESS REQUIRING THE ACCUMULATION OF MULTIPLE GENETIC ALTERATIONS, INFLUENCED BY A PATIENT'S GENETIC PREDISPOSITION AS WELL AS BY ENVIRONMENTAL INFLUENCES, INCLUDING TOBACCO, ALCOHOL, CHRONIC INFLAMMATION, AND VIRAL INFECTION. TUMORIGENIC GENETIC ALTERATIONS CONSIST OF TWO MAJOR TYPES: TUMOR SUPPRESSOR GENES, WHICH PROMOTE TUMOR DEVELOPMENT WHEN INACTIVATED; AND ONCOGENES, WHICH PROMOTE TUMOR DEVELOPMENT WHEN ACTIVATED. TUMOR SUPPRESSOR GENES CAN BE INACTIVATED THROUGH GENETIC EVENTS SUCH AS MUTATION, LOSS OF HETEROZYGOSITY, OR DELETION, OR BY EPIGENETIC MODIFICATIONS SUCH AS DNA METHYLATION OR CHROMATIN REMODELING. ONCOGENES CAN BE ACTIVATED THROUGH OVEREXPRESSION DUE TO GENE AMPLIFICATION, INCREASED TRANSCRIPTION, OR CHANGES IN STRUCTURE DUE TO MUTATIONS THAT LEAD TO INCREASED TRANSFORMING ACTIVITY. THIS REVIEW FOCUSES ON THE MOLECULAR MECHANISMS OF ORAL CARCINOGENESIS AND THE USE OF BIOLOGIC THERAPY TO SPECIFICALLY TARGET MOLECULES ALTERED IN OSCC. THE RAPID PROGRESS THAT HAS BEEN MADE IN OUR UNDERSTANDING OF THE MOLECULAR ALTERATIONS CONTRIBUTING TO THE DEVELOPMENT OF OSCC IS LEADING TO IMPROVEMENTS IN THE EARLY DIAGNOSIS OF TUMORS AND THE REFINEMENT OF BIOLOGIC TREATMENTS INDIVIDUALIZED TO THE SPECIFIC CHARACTERISTICS OF A PATIENT'S TUMOR. 2008 14 2975 31 GENETIC AND MOLECULAR ALTERATIONS ASSOCIATED WITH ORAL SQUAMOUS CELL CANCER (REVIEW). THE DEVELOPMENT OF ORAL SQUAMOUS CELL CANCER (OSCC) IS A MULTISTEP PROCESS INVOLVING THE ACCUMULATION OF MULTIPLE GENETIC ALTERATIONS MODULATED BY GENETIC PRE-DISPOSITION AND ENVIRONMENTAL INFLUENCES SUCH AS TOBACCO AND ALCOHOL USE, CHRONIC INFLAMMATION, AND VIRAL INFECTIONS. ALL OF THESE FACTORS CAN LEAD TO A WIDE RANGE OF GENETIC AND MOLECULAR ALTERATIONS THAT CAN BE DETECTED USING A RANGE OF MOLECULAR STUDIES. THE ALTERATIONS MOSTLY AFFECT TWO LARGE GROUPS OF GENES: ONCOGENES AND TUMOR SUPPRESSOR GENES, WHICH CAN BE EITHER INACTIVATED OR OVEREXPRESSED THROUGH MUTATIONS, LOSS OF HETEROZYGOSITY, DELETIONS, OR EPIGENETIC MODIFICATIONS SUCH AS METHYLATION. OTHER MOLECULES THAT ARE CLOSELY ASSOCIATED WITH TUMOR PATHOGENESIS AND PROGNOSIS ALSO EXIST AND WARRANT FURTHER STUDY. IMPORTANT ADVANCES IN MOLECULAR BIOLOGY ARE HELPING TO SHED LIGHT ON ORAL CANCER AND THUS AIDING IN THE EARLY DIAGNOSIS AND DEVELOPMENT OF NEW PERSONALIZED TREATMENT APPROACHES. THE PURPOSE OF THE REVIEW IS TO EXPLORE THE GENETIC AND MOLECULAR ALTERATIONS ASSOCIATED WITH OSCC. 2009 15 4431 35 MOLECULAR CARCINOGENESIS OF HEPATOCELLULAR CARCINOMA AND INTRAHEPATIC CHOLANGIOCARCINOMA: ONE STEP CLOSER TO PERSONALIZED MEDICINE? HEPATOCELLULAR CARCINOMA (HCC) AND INTRAHEPATIC CHOLANGIOCARCINOMA (ICC) ARE THE TWO MAJOR FORMS OF PRIMARY LIVER CANCERS (PLC), ACCOUNTING FOR APPROXIMATELY 90% AND 5% RESPECTIVELY. THE INCIDENCE OF EACH IS INCREASING RAPIDLY IN THE WESTERN WORLD, HOWEVER OUR KNOWLEDGE OF THE UNDERLYING MECHANISMS REMAINS LIMITED AND THE OUTCOME, DISMAL. THE ETIOLOGIES OF EACH VARY GEOGRAPHICALLY; NEVERTHELESS, CHRONIC INFLAMMATION HAS BEEN IDENTIFIED IN MORE THAN 80% OF THE CASES AND APPEARS TO BE A KEY MEDIATOR IN ALTERING THE LIVER MICROENVIRONMENT, INCREASING THE RISK OF CARCINOGENESIS. HOWEVER, SINCE NOT ALL HCC AND ESPECIALLY ICC CASES HAVE A RECOGNIZED RISK FACTOR, THERE ARE CURRENTLY TWO PROPOSED MODELS FOR LIVER CARCINOGENESIS. THE CLONAL EVOLUTION MODEL DEMONSTRATES A MULTI-STEP PROCESS OF TUMOR DEVELOPMENT FROM PRECANCEROUS LESIONS TO METASTATIC CARCINOMA, ARISING FROM THE ACCUMULATION OF GENETIC AND EPIGENETIC CHANGES IN A CELL IN THE SETTING OF CHRONIC INFLAMMATION. WHILE THE MAJORITY OF CASES DO OCCUR AS A CONSEQUENCE OF CHRONIC INFLAMMATION, MOST INDIVIDUALS WITH CHRONIC INFECTION DO NOT DEVELOP PLC, SUGGESTING THE INVOLVEMENT OF INDIVIDUAL GENETIC AND ENVIRONMENTAL FACTORS. FURTHER, SINCE HEPATOCYTES AND CHOLANGIOCYTES BOTH HAVE REGENERATIVE POTENTIAL AND ARISE FROM THE SAME BI-POTENTIAL PROGENITOR CELL, THE MORE RECENTLY PROPOSED CANCER STEM CELL MODEL IS GAINING ITS DUE ATTENTION. THE INTEGRATION OF THESE MODELS AND THE CONSTANT IMPROVEMENT IN MOLECULAR PROFILING PLATFORMS IS ENABLING A BROADER UNDERSTANDING OF THE MECHANISMS UNDERLYING THESE TWO DEVASTATING MALIGNANCIES, PERHAPS MOVING US CLOSER TO A NEW WORLD OF MOLECULARLY-INFORMED PERSONALIZED MEDICINE. 2011 16 3683 40 INFLAMMATION, MICROBIOTA, AND PROSTATE CANCER. CONTEXT: CHRONIC INFLAMMATION OF THE PROSTATE HAS BEEN ASSOCIATED WITH PRENEOPLASTIC LESIONS AND CANCER DEVELOPMENT. MULTIPLE CAUSES HAVE BEEN CONSIDERED FOR CHRONIC INFLAMMATION OF THE PROSTATE. INFLAMMATORY CYTOKINES SUCH AS INTERLEUKINS ARE IMPLICATED IN PROSTATE CARCINOGENESIS AND DEVELOPMENT. OBJECTIVE: TO EVALUATE LITERATURE PUBLISHED ON ETIOLOGICAL FACTORS, URINARY MICROBIOTA, MORPHOLOGICAL FEATURES OF PROLIFERATIVE INFLAMMATORY ATROPHY AND HIGH-GRADE PROSTATE INTRAEPITHELIAL NEOPLASIA, GENETIC POLYMORPHISMS, INFLAMMATORY STRESS, AND CYTOKINE SIGNALING. EVIDENCE ACQUISITION: WE SEARCHED LITERATURE FROM PUBMED FROM 2010 AND ALSO INCLUDED THE MOST IMPORTANT PUBLICATIONS FROM THE PREVIOUS PERIOD. EVIDENCE SYNTHESIS: PROSTATE CANCER INFLAMMATION AND PREMALIGNANT LESIONS HAVE BEEN FREQUENTLY DISCUSSED IN SCIENTIFIC LITERATURE. A LIMITED NUMBER OF MODELS ARE AVAILABLE FOR STUDYING INFLAMMATION AND PREMALIGNANT LESIONS. HOWEVER, MORPHOLOGICAL PATHOLOGY COULD BE COMPLEMENTED BY ANALYSIS OF GENE POLYMORPHISMS IN THESE PATIENTS AND APPROPRIATE FUNCTIONAL STUDIES. CONCLUSIONS: PROSTATITIS COULD BE CAUSED BY BACTERIAL OR VIRAL INFECTIONS, DIETARY COMPOUNDS, AND CHANGES IN TESTOSTERONE:ESTRADIOL RATIO. IN SOME CASES, THE MICROBIOTA CAN EXERT DIRECT EFFECTS ON CANCER DEVELOPMENT. PROSTATE INFLAMMATORY ATROPHY OR HIGH GRADE PROSTATE INTRAEPITHELIAL NEOPLASIA HAVE BEEN ASSOCIATED WITH RESPONSE TO CELLULAR STRESS AND HAVE BEEN DISCUSSED IN CONNECTION TO EARLY CANCER DEVELOPMENT. A LARGE NUMBER OF GENETIC POLYMORPHISMS HAVE BEEN IDENTIFIED IN INFLAMMATORY PROSTATE. GENETIC AND EPIGENETIC ALTERATIONS MAY BE A CONSEQUENCE OF THE PROINFLAMMATORY STRESS IN THE PROSTATE. PROINFLAMMATORY CYTOKINES INTERLEUKIN-6 AND -8 CONTRIBUTE TO PROSTATE MALIGNANCY; HOWEVER, THEIR FUNCTION WAS MORE FREQUENTLY INVESTIGATED IN CANCER TISSUE RATHER THAN IN INFLAMMATION. PATIENT SUMMARY: WE PERFORMED A REVIEW OF RECENT LITERATURE RELATED TO PROSTATE INFLAMMATION, MICROBIOTA, AND PROSTATE CANCER. NEW FUNCTIONAL APPROACHES ARE REQUIRED FOR A BETTER UNDERSTANDING OF THE ROLE OF INFLAMMATION AND CANCER DEVELOPMENT. 2016 17 5360 31 RECENT ADVANCEMENTS IN COMPREHENSIVE GENETIC ANALYSES FOR HUMAN HEPATOCELLULAR CARCINOMA. HEPATOCELLULAR CARCINOMA (HCC) TYPICALLY DEVELOPS IN THE LIVER WITH CHRONIC HEPATITIS AND CIRRHOSIS, AND ACTIVATION OF ONCOGENES AND INACTIVATION OF TUMOR SUPPRESSOR GENES OCCURS DURING CARCINOGENESIS VIA GENETIC AND EPIGENETIC MECHANISMS. RECENT ADVANCEMENTS IN THE DEVELOPMENT OF ANALYSES FOR EXAMINING THE CANCER GENOME HAVE REVEALED INFORMATION REGARDING GENETIC ALTERATIONS IN HCC TISSUES. ACCORDING TO PREVIOUS STUDIES, THE INCIDENCE OF RECURRENT GENETIC ALTERATIONS IN INDIVIDUAL GENES WAS THOUGHT TO BE RELATIVELY RARE AND LIMITED TO A SUBSET OF A FEW CANCER-SPECIFIC GENES SUCH AS TUMOR SUPPRESSOR P53, RB GENES AND ONCOGENES SUCH AS CTNNB1. HOWEVER, RECENT WHOLE-GENOME ANALYSES AND EXOME SEQUENCING OF TUMOR DNA HAVE REVEALED NUMEROUS NOVEL ALTERATIONS OF CANCER-RELATED GENES AND PATHWAYS CRITICAL FOR HCC DEVELOPMENT. IN ADDITION, VARIOUS RISK FACTORS FOR HCC, SUCH AS THE PRESENCE OR ABSENCE OF HEPATITIS B AND C VIRUS, MAY AFFECT THE MUTATION PROFILE OF THE CORRESPONDING CANCER GENOME. ON THE OTHER HAND, GENOME-WIDE ASSOCIATION STUDIES HAVE ALSO IDENTIFIED IMPORTANT SINGLE-NUCLEOTIDE POLYMORPHISMS INVOLVED IN HCC DEVELOPMENT, WHICH MAY ALLOW DETECTION OF A GROUP AT HIGH RISK OF HCC EMERGENCE. SUCH ANALYSES WILL CLARIFY HOW THIS MALIGNANCY CAN BE TREATED, DIAGNOSED AND PREVENTED MORE EFFECTIVELY. 2013 18 1844 40 EFFECTS OF THE LIFESTYLE HABITS IN BREAST CANCER TRANSCRIPTIONAL REGULATION. THROUGH RESEARCH CARRIED OUT IN THE LAST 25 YEARS ABOUT THE BREAST CANCER ETIOLOGY, IT HAS BEEN POSSIBLE TO ESTIMATE THAT LESS THAN 10 % OF PATIENTS WHO ARE DIAGNOSED WITH THE CONDITION ARE CARRIERS OF SOME GERMLINE OR SOMATIC MUTATION. THE CLINICAL REPORTS OF BREAST CANCER PATIENTS WITH HEALTHY TWINS AND THE DEVELOPMENT OF DISEASE IN WOMEN WITHOUT HIGH PENETRANCE MUTATIONS DETECTED, WARN THE PARTICIPATION MORE FACTORS IN THE TRANSFORMATION PROCESS. THE HIGH INCIDENCE OF MAMMARY ADENOCARCINOMA IN THE MODERN WOMAN AND THE URGENT NEED FOR NEW METHODS OF PREVENTION AND EARLY DETECTION HAVE DEMANDED MORE INFORMATION ABOUT THE ROLE THAT ENVIRONMENT AND LIFESTYLE HAVE ON THE TRANSFORMATION OF MAMMARY GLAND EPITHELIAL CELLS. OBESITY, ALCOHOLISM AND SMOKING ARE FACTORS THAT HAVE SHOWN A CLOSE CORRELATION WITH THE RISK OF DEVELOPING BREAST CANCER. AND ALTHOUGH THESE CONDITIONS AFFECT DIFFERENT CELL REGULATION LEVELS, THE STUDY OF ITS EFFECTS IN THE MECHANISMS OF TRANSCRIPTIONAL AND EPIGENETIC REGULATION IS CONSIDERED CRITICAL FOR A BETTER UNDERSTANDING OF THE LOSS OF IDENTITY OF EPITHELIAL CELLS DURING CARCINOGENESIS OF THIS TISSUE. THE MAIN OBJECTIVE OF THIS REVIEW WAS TO ESTABLISH THE IMPORTANCE OF CHANGES OCCURRING TO TRANSCRIPTIONAL LEVEL IN THE MAMMARY GLAND AS A CONSEQUENCE OF ACUTE OR CHRONIC EXPOSURE TO HARMFUL PRODUCTS SUCH AS OBESITY-CAUSING FOODS, ETHANOL AND CIGARETTE SMOKE COMPONENTS. AT ANALYZE THE MAIN STUDIES RELATED TO TOPIC, IT HAS CONCLUDED THAT THE UNDERSTANDING OF EFFECTS CAUSED BY THE LIFESTYLE FACTORS IN PERFORMANCE OF THE TRANSCRIPTIONAL MECHANISMS THAT DETERMINE GENE EXPRESSION OF THE MAMMARY GLAND EPITHELIAL CELLS, MAY HELP EXPLAIN THE DEVELOPMENT OF THIS DISEASE IN WOMEN WITHOUT GENETIC PROPENSITY AND DIFFERENT PHENOTYPIC MANIFESTATIONS OF THIS CANCER TYPE. 2016 19 4316 32 MICRORNAS AS NON-INVASIVE DIAGNOSTIC BIOMARKERS FOR GASTRIC CANCER: CURRENT INSIGHTS AND FUTURE PERSPECTIVES. NON-INVASIVE DIAGNOSTIC BIOMARKERS MAY CONTRIBUTE TO AN EARLY IDENTIFICATION OF GASTRIC CANCER (GC) AND IMPROVE THE CLINICAL MANAGEMENT. UNFORTUNATELY, NO SENSITIVE AND SPECIFIC SCREENING BIOMARKERS ARE AVAILABLE YET AND THE CURRENTLY AVAILABLE APPROACHES ARE LIMITED BY THE NATURE OF THE DISEASE. GC IS A HETEROGENIC DISEASE WITH VARIOUS DISTINCT GENETIC AND EPIGENETIC EVENTS THAT OCCUR DURING THE MULTIFACTORIAL CASCADE OF CARCINOGENESIS. MICRORNAS (MIRNAS) ARE COMMONLY DEREGULATED IN GASTRIC MUCOSA DURING THE HELICOBACTER PYLORI INFECTION AND IN STEPWISE MANNER FROM CHRONIC GASTRITIS, THROUGH PRENEOPLASTIC CONDITIONS SUCH AS ATROPHIC GASTRITIS AND INTESTINAL METAPLASIA, TO EARLY DYSPLASIA AND INVASIVE CANCER. IDENTIFICATION OF MIRNAS IN BLOOD IN 2008 LED TO A GREAT INTEREST ON MIRNA-BASED DIAGNOSTIC, PROGNOSTIC BIOMARKERS IN GC. IN THIS REVIEW, WE PROVIDE THE MOST RECENT SYSTEMATIC REVIEW ON THE EXISTING STUDIES RELATED TO MIRNAS AS DIAGNOSTIC BIOMARKERS FOR GC. HERE, WE SYSTEMATICALLY EVALUATE 75 STUDIES RELATED TO DIFFERENTIAL EXPRESSION OF CIRCULATING MIRNAS IN GC PATIENTS AND PROVIDE NOVEL VIEW ON VARIOUS HETEROGENIC ASPECTS OF THE EXISTING DATA AND SUMMARIZE THE METHODOLOGICAL DIFFERENCES. FINALLY, WE HIGHLIGHT SEVERAL IMPORTANT ASPECTS CRUCIAL TO IMPROVE THE FUTURE TRANSLATIONAL AND CLINICAL RESEARCH IN THE FIELD. 2018 20 736 36 CANCER STEM CELLS--NEW APPROACH TO CANCEROGENENSIS AND TREATMENT. RECENTLY, THERE IS AN INCREASING EVIDENCE SUPPORTING THE THEORY OF CANCER STEM CELLS NOT ONLY IN LEUKEMIA BUT ALSO IN SOLID CANCER. TO DATE, THE EXISTENCE OF CANCER STEM CELLS HAS BEEN PROVEN IN ACUTE AND CHRONIC MYELOID LEUKEMIA, IN BREAST CANCER, IN BRAIN TUMORS, IN LUNG CANCER AND GASTROINTESTINAL TUMORS. THIS REVIEW IS FOCUSING ON THE RECENT DISCOVERY OF STEM CELLS IN LEUKEMIA, HUMAN BRAIN TUMORS AND BREAST CANCER. A SMALL POPULATION OF CELLS IN THE TUMOR (LESS THAN 1%) SHOWS THE POTENTIAL TO GIVE RISE TO THE TUMOR AND ITS GROWTH. THESE CELLS HAVE A SUBSTANTIAL CHARACTERISTIC OF STEM CELLS--ABILITY FOR SELF-RENEWAL WITHOUT LOSS OF PROLIFERATION CAPACITY WITH EACH CELL DIVISION. FURTHERMORE THEY ARE IMMORTAL, RATHER RESISTANT TO TREATMENT AND EXPRESS TYPICAL MARKERS OF STEM CELLS. THE ORIGIN OF THESE RESIDENT CANCER STEM CELLS IS NOT CLEAR. WHETHER THE CANCER STEM CELLS ORIGINATE FROM NORMAL STEM CELLS IN CONSEQUENCE OF GENETIC AND EPIGENETIC CHANGES AND/OR REDIFFERENTIATION FROM SOMATIC TUMOR CELLS TO THE STEM-LIKE CELLS REMAINS TO BE INVESTIGATED. WE PROPOSE THE IDEA OF THE RELATION BETWEEN NORMAL TISSUE STEM CELLS AND CANCER STEM CELLS AND THEIR POPULATIONS--PROGENITOR CELLS. BASED ON THIS WE HIGHLIGHT ONE OF THE MAJOR CHARACTERISTIC OF STEM CELL--PLASTICITY, WHICH IS EQUALLY IMPORTANT IN THE PHYSIOLOGICAL REGENERATION PROCESS AS WELL AS CARCINOGENESIS. FURTHERMORE, WE CONSIDER THE MICROENVIRONMENT AS A LIMITING FACTOR FOR TUMOR GENESIS IN AML, BREAST CANCER AND BRAIN TUMORS. THUS THE BIOLOGICAL PROPERTIES OF CANCER STEM CELLS ARE JUST BEGINNING TO BE REVEALED, THE CONTINUATION OF THESE STUDIES SHOULD LEAD TO THE DEVELOPMENT OF CANCER STEM CELLS TARGET THERAPIES FOR CANCER TREATMENT. 2008