Molekularna stratifikacija kolorektalnog raka

Colorectal cancer (CRC) is one of the most common cancers and one of the leading causes of cancer death in the Western world. The disease arises from the accumulation of mutations in oncogenes, tumor suppressor genes and mismatch repair genes during progression from normal colon epithelium to adenoma and metastatic carcinoma. Improved understanding of genetic events that underline tumor development and progression may contribute to new strategies for prevention, diagnosis as well as for therapy. The results of Human genome project showed that each person has its unique genetic “signature” as a consequence of a large number of inherited genetic variations. There are also sporadic molecular changes specific for each tumor type. This mini review will give some information about the most frequent molecular genetics changes in colorectal cancer and its molecular stratification due to its heredity, germline pharmacogenetic markers, somatic mutations and microsatellite instability.Kolorektalni karcinom je jedan od najčešćih zloćudnih tumora i jedan od vodećih uzroka smrti od raka u zemljama razvijenog svijeta. Oboljenje nastaje kroz duži niz godina tijekom kojih kao posljedica mutacija u onkogenima, tumor supresorskim genima i genima za popravak DNA iz normalne sluznice kolona preko adenoma nastaje zloćudni invazivni karcinom. Dobro poznavanje molekularne podloge nastanka i napredovanja kolorektalnog karcinoma doprinosi boljoj prevenciji, ranoj dijagnostici i uspješnijoj terapiji ovog zloćudnog tumora. Rezultati istraživanja u području molekularne patologije raka ukazuju na to da svaki tumor posjeduje svoj vlastiti genetski otisak koji je rezultat individualnih, za taj tumor specifičnih, molekularnih promjena ali i genetičkih karakteristika oboljele osobe. U ovom kratkom preglednom radu opisane su najčešće molekularno genetičke promjene u kolorektalnom karcinomu te molekularna stratifikacija ovog zloćudnog tumora s obzirom na nasljednost, farmakogenetske biljege, stečene mutacije i mikrosatelitnu nestabilnost

Molekularni podtipovi kolorektalnog karcinoma – kratki pregled

Colorectal cancer (CRC) is one of the most common cancers and one of the leading causes of cancer death in the Western world. The majority of colorectal cancers arise in sporadic form. The disease arises from the accumulation of mutations in oncogenes, tumor suppressor genes and mismatch repair genes during progression from normal colon epithelium to adenoma and metastatic carcinoma. Colorectal Cancer Subtyping Consortium describes four consensus molecular subtypes (CMS) of CRC: CMS1 (14%, microsatellite instability, immune, strong immune activation), CMS2 (37%, canonical, WNT and MYC signaling activation), CMS3 (13%, metabolic, epithelial and metabolic dysregulation) and CMS4 (23%, mesenchymal, transforming growth factor-activation), while 13% of colorectal cancers remained mixed or “unclassified”. This mini review will give some information about the most frequent molecular genetics changes in colorectal cancer and its molecular classification in four CMS subtypes due to its morphology, gene expression profile, somatic mutations and microsatellite instability.Kolorektalni karcinom je jedan od najčešćih zloćudnih tumora i jedan od vodećih uzroka smrti od raka u zemljama razvijenog svijeta, a najčešće se javlja u sporadičnom obliku. Ovaj zloćudni tumor nastaje kroz duži niz godina tijekom kojih kao posljedica mutacija u onkogenima, tumor supresorskim genima i genima za popravak DNA iz normalne sluznice kolona preko adenoma nastaje zloćudni metastatski karcinom. Nova CMS (od engl. Consensus Molecular Subtypes) klasifikacija dijeli karcinome kolorektuma na četiri CMS podtipa: CMS1 (14%, pozitivni na mikrosatelitnu nestabilnost, jaka imunološka infiltracija tumora), CMS2 (37%, epitelni koji slijede adenom-karcinom slijed, aktivacija Wnt te Myc signalnog puta), CMS3 (13%, metabolički, epitelni s metaboličkom disregulacijom) te CMS4 (23%, mezenhimalni, jaka imunološka infiltracija strome, aktivacija TGF- signalnog puta) dok 13% tumora ostaje neklasificirano odnosno miješanog podtipa. U ovom kratkom preglednom radu opisane su molekularno genetičke promjene u karcinomima kolorektuma te molekularna klasifikacija ovog zloćudnog tumora na molekularne (CMS) podtipove s obzirom na morfologiju, transkriptomski profil, stečene mutacije i mikrosatelitnu nestabilnost

Molekularna stratifikacija sporadičnog i nasljednog kolorektalnog raka kratki pregled

Colorectal cancer (CRC) is one of the most common cancers and one of the leading causes of cancer death in the Western world. The disease arises from the accumulation of mutations in oncogenes, tumor suppressor genes and mismatch repair genes during progression from normal colon epithelium to adenoma and metastatic carcinoma. The majority of colorectal cancers arise in sporadic form. About one-third of patients with CRC have a family history of cancer and elevated risk for this malignant disease. However, only 5% of CRC arise from a germline mutation in high penetrant genes, adenomatous polyposis coli (APC) gene and DNA mismatch repair (MMR) genes. The most common hereditary CRC syndrome is Lynch syndrome defined by hereditary germline mutations in one the of MMR genes. The term hereditary non-polyposis colorectal cancer (HNPCC), previously used interchangeably with Lynch syndrome, now refers to a broader spectrum of familial CRC disorders that can mimic some clinical features of Lynch syndrome, but without germline mutations in MMR genes characteristic for Lynch syndrome. Distinguishing between the HNPCC disorders is important for clinicians, as the approach to surveillance for patients and their family members differs according to risk for CRC associated with each syndrome. This mini review will give some information about the most frequent molecular genetics changes in sporadic and hereditary colorectal cancer and its molecular stratification due to its heredity, somatic mutations and microsatellite instability.Kolorektalni karcinom je jedan od najčešćih zloćudnih tumora i jedan od vodećih uzroka smrti od raka u zemljama razvijenog svijeta. Bolest nastaje kroz duži niz godina tijekom kojih kao posljedica mutacija u onkogenima, tumor supresorskim genima i genima za popravak DNA iz normalne sluznice kolona preko adenoma nastaje zloćudni metastatski karcinom. Najveći broj karcinoma kolorektuma javlja se u sporadičnom obliku dok jedna trećina bolesnika ima pozitivnu obiteljsku anamnezu i izložena je povećanom riziku da oboli od ovog zloćudnog tumora. Međutim, svega 5% karcinoma kolorektuma nastaje kao posljedica nasljedne mutacije u genu APC ili genima za popravak krivo sparenih baza u DNA (MMR). Najčešći nasljedni sindrom karcinoma kolorektuma je sindrom Lynch (LS) koji se nasljeđuje mutacijama u genima za popravak DNA. Pojam nasljednog nepolipoznog karcinoma kolorektuma (HNPCC) koji se koristio kao sinonim za LS danas se povezuje sa spektrom obiteljskih karcinoma kolorektuma koji imaju kliničke karakteristike slične LS, ali oboljeli nisu nosioci nasljednih mutacija MMR gena. Razlikovanje nasljednih sindroma objedinjenih pod nazivom HNPCC važno je za kliničare radi pravilnog praćenja oboljelih i članova njihovih obitelji jer se isti razlikuju i po sklonosti razvoju karcinoma kolorektuma. U ovom kratkom preglednom radu opisane su molekularno genetičke promjene u sporadičnom i nasljednom kolorektalnom karcinomu te molekularna stratifikacija ovog zloćudnog tumora s obzirom na nasljednost, stečene mutacije i mikrosatelitnu nestabilnost

SNP CYTOKINE POLYMORPHYSMS, PERINATAL INFECTION AND CEREBRAL PALSY

Cerebralna paraliza je najčešća neurološka bolest u djece, uzrokovana neprogresivnim oštećenjem mozga u razvoju. Etiologija i patogeneza razvoja cerebralne paralize nepoznata je u velikom broju slučajeva. Danas se smatra da je jedan od vodećih uzroka cerebralne paralize prijevremeni porođaj, dok se samo u manjeg broja oboljelih od cerebralne paralize nastalo neurorazvojno odstupanje može povezati s hipoksijom nastalom tijekom porođaja. Tijekom posljednjeg desetljeća pokazalo se da su prijevremeni porođaj i komplikacije u novorođenčeta najčešće posljedica klinički neprepoznate – subkliničke - intrauterine infekcije. Mikroorganizmi, odnosno njihovi produkti i endotoksini u fetusu, potiču ekspresiju gena za citokine, lučenje citokina i sistemski upalni odgovor koji se naziva FIRS (od engl. Fetal Inflammatory Response Syndrome). Pokazalo se da je FIRS glavni čimbenik koji može inducirati početak prijevremenog porođaja. Odnos između proupalnih i protuupalnih citokina u mozgu novorođenčeta kritičan je čimbenik nastanka oštećenja mozga. Težina neuromotornog odstupanja ne ovisi isključivo o težini hipoksično-ishemičkog oštećenja, već je rezultat kompliciranih interakcija većeg broja etioloških čimbenika i genetske predispozicije pojedinca na osnovi genotipa polimorfizama gena za proupalne i protuupalne citokine.Cerebral palsy (CP) is the most common neurological disorder in children attributed to non-progressive disturbances in the developing fetal or infant brain. The cause and pathogenesis of CP is multifactorial and continues to be poorly understood. Prematurity is considered to be the leading risk factor for the development of CP. In recent times, intrauterine infection/inflammation has been identified as the most common cause of preterm delivery and neonatal complications. Microorganisms or their products stimulate the production of cytokines and a systemic response termed FIRS (Fetal Inflammatory Response Syndrome) in the fetus. Activation of the cytokine network and elevated levels of proinflammatory cytokines can cause white matter brain damage and preterm delivery, as well as the future development of CP. The balance between pro- and anti-inflammatory cytokines in the neonatal brain is likely to be critical in determining the initiation, development and consequences of cerebral injury. Individual infants display a spectrum of severity of damage following apparently comparable insults. Such variation may depend on the complicated interaction of the multiple etiological factors and on the genetic susceptibility of the individual including polymorphisms in pro- and anti-inflammatory cytokine genotypes

Alterations of FHIT and P53 genes in keratocystic odontogenic tumor, dentigerous and radicular cyst

BACKGROUND: The purpose of this study was to determine fragile histidine triad (FHIT) and p53 protein expression, and to analyze FHIT and p53 gene status in keratocystic odontogenic tumor (KOT), dentigerous cysts (DC) and radicular cysts (RC). ----- METHODS: The methods used were immunohistochemistry and molecular genetic methods including loss of heterozygosity (LOH) and gene sequencing. ----- RESULTS: FHIT protein expression was different among groups. Aberrant expression was the highest in KOT, then in RC and DC. p53 protein expression was different among groups. LOH in paraffin-embedded specimens was detected in 22.6% and 12.9% for FHIT and p53 respectively. Mutation of p53 gene at codon 237 was observed in only two specimens (one KOT and one DC). Of the six frozen specimens, three exhibited FHIT gene LOH (two RC and one KOT). KOT showed loss of exons 6-7 at FHIT locus and mutation at codon 237 at p53 locus, but this could be a chance result. ----- CONCLUSION: Aberrations of FHIT and p53 genes/proteins could be considered markers responsible for the development of odontogenic lesions

Comparison of Three RT-PCR Based Methods for Relative Quantification of mRNA

Comparison of three RT-PCR based methods: semi-quantitative, competitive and real--time RT-PCR for relative quantification of mRNA is presented. Aminopeptidase N expressed on human promyeloid HL-60 cell line, at basal and activated state, served as a model for comparison. HL-60 cells were stimulated with IFN- (6 ng/mL) for 72 h at 37 oC, total cellular RNA was isolated, reverse transcribed to cDNA and semi-quantitative, competitive and real-time RT-PCR were performed to obtain the relative levels of mRNA for aminopeptidase N. The data obtained showed that all three RT-PCR based methods gave reliable and comparable results, i.e. approximately twofold increase of aminopeptidase N mRNA on IFN- stimulated HL-60 cells. Thus, in spite of rapid advances made in the area of real-time RT-PCR, end-point RT-PCR such as competitive and semi-quantitative RT- -PCR, although laborious and time consuming, may still remain useful techniques for relative mRNA quantification when small number of samples are to be analyzed

Prothrombin 3'end Gene Variants in Patients With Sporadic Colon Adenocarcinoma

Background/ Aim: Thrombin plays significant roles in various types of cancer. However, the expression levels of prothrombin, the thrombin precursor, in cancer remain unclear. Variants of the 3'end of the prothrombin gene lead to increased prothrombin expression. This study aimed to analyze prothrombin 3'end gene variants in colon tumor and adjacent normal tissue samples. Materials and Methods: The study group consisted of 93 patients suffering from colon adenocarcinoma. The 3'end of the prothrombin gene was analyzed by DNA sequencing. Results: Three variants, all previously associated with increased prothrombin expression were detected. Frequency of the FII 19911G allele was 46.77% and 47.85% in tumor and normal tissue, respectively. For the FII 20210A allele, the detected frequencies were 2.15% and 1.61%, respectively. The frequency of the FII c.1824T allele was 0.54% in both tissues. Four patients showed different genotypes in tumor and normal tissue. Conclusion: Prothrombin 3' end gene variants may play a role in colorectal cancer