Author/Editor		Gojkovič, Andreja; Grošelj, Mojca
Title		Ugotavljanje genskih sprememb pri raku želodca
Translated title		Identification of genes alterations in stomach cancer
Type		članek
Source		Med Razgl
Vol. and No.		Letnik 38, št. 1
Publication year		1999
Volume		str. 5-28
Language		slo
Abstract		Stomach cancer (gastric adeno-cacinoma) is a common malignant disease in Slovenia. The Lauren's classification distinguishes between a well differentiated intestinal type and a poorly differentiated diffuse type of the disease, which differ in their development and the characteristic sequence of genetic changes. The purpose of this first study done on a selected sample of Slovene patients was to investigate the allele loss of several tumor suppressor genes (APC, p53, Rb, nm23 and DCC) and thus distinguish between the intestinal and diffuse type of gastric adenocarcinoma in the Slovene population. Another aim of this work was to introduce the newest method for investigating the allele loss. Seventeen randomly selected frozen samples of adenocarcinomas and adjacent normal tissues were obtained from 17 patients treated by surgery in 1997. The polymerase chain reaction was used for multiplying microsatellite sequences of the tumor suppressor genes. The obtained PCR products were analysed with the capillary electrophoresis in the automatic gene analyser. Loss of heterozigosity was found in 17% of samples for APC, in 50% for p53, and in 100% for DCC. There was no loss of heterozigosity for Rb and nm23. Dfferences in genetic alterations between the intestinal and diffuse type of adenocarcinoma in the Slovene population were identified. The results represent a good starting point for the multiplex polymerase chain reaction using a larger set of genetic markers, and for its application in the research of some other, not yet investigated tumor suppressor and mismatch repair genes.
Summary		Žlezni rak (adenokarcinom) želodca je pogosto maligno obolenje v Sloveniji. Po Laurenovi razvrstitvi ga delimo na intestinalno, dobro diferencirano, in difuzno, slabo diferencirano obliko. Poti nastanka obeh oblik naj bi se razlikovali po značilnem zaporedju genetskih sprememb. V naši raziskavi smo želeli na izbranem vzorcu intestinalne in difuzne oblike adenokarcinomov želodca ugotoviti izgubo alela nekaterih zaviralnih genov (APC, p53, Rb, nm23 in DCC) in ugotoviti morebitno razliko med obema oblikama. Hkrati smo želeli uvesti novo, najsodobnejšo metodo preiskovanja izgube alelov. Proučevali smo vzorce tumorskega in zdravega tkiva želodca, odvzete sedemnajstim naključno izbranim bolnikom z rakom želodca, operiranim v letu 1997. Za pomnoževanje mikrosatelitnih zaporedij zaviralnih genov smo uporabili verižno reakcijo s polimerazo. Dobljene PCR-pridelke smo analizirali po načelu kapilarne elektroforeze s pomočjo avtomatskega genskega analizatorja. Za gen APC smo ugotovili izgubo heterozigotnosti v 17 %, za gen p53 v 50 % in za gen DCC v 100 % primerov. Pri genih Rb in nm23 nismo ugotovili izgube heterozigotnosti. Ugotovili smo razliko v pojavljanju genskih sprememb pri intestinalni in difuzni obliki. Naša raziskava je dala osnove za nadaljnje iskanje najugodnejših pogojev za izvedbo obsežnejše multipleks verižne reakcije s polimerazo in za njeno uporabo pri preiskavi še neraziskanih genov.
Descriptors		STOMACH NEOPLASMS ADENOCARCINOMA NEOPLASM STAGING DNA ELECTROPHORESIS, AGAR GEL POLYMERASE CHAIN REACTION BASE SEQUENCE ELECTROPHORESIS, CAPILLARY ALLELES