MOLECULAR EVALUATION OF t(14;18)(bcl-2/IgH) TRANSLOCATION IN FOLLICULAR LYMPHOMA AT DIAGNOSIS USING PARAFFIN-EMBEDDED TISSUE SECTIONS
Makaleler > Tam Makale · 2012
Yazarlar: Nur SELVİ GÜNEL, Buket KOSOVA, Mine HEKİMGİL, Cumhur GÜNDÜZ, Burçin KAYMAZ, Emin KARACA, Güray SAYDAM, Murat TOMBULOĞLU, Filiz Buyukkececi, Seckin Cagirgan, Yeşim ERTAN, Nejat TOPÇUOĞLU
Turkish Journal of Hematology, SCI Expanded İndekslerine Giren Dergi, Uluslararası, Wos, 2012, cilt 29, ss 126-134
Özet
OBJECTIVE: Follicular lymphoma (FL) is one of the most common lymphomas, and is characterized by t(14;18)(q32;q21) in more than 80% of patients. The aim of this study was to determine the rate of t(14;18) positivity based onthe detection of mbr or mcr in paraffin-embedded tissue samples. MATERIAL AND METHODS: The study included 32 paraffin-embedded tissue samples collected from 32 consecutive FL patients that were diagnosed and followed-up at our hospital between 1999 and 2006. The MBR breakpoint wasidentified based on real-time PCR using a LightCycler v.2.0 t(14;18) Quantification Kit (MBR), multiplex PCR, and seminestedPCR. To identify the mcr breakpoint, real-time PCR was performed using specific primers and the FastStart DNAMaster SYBR Green I Kit. To detect t(14;18) via fluorescence in situ hybridization (FISH) nuclei from paraffin-embeddedtissue sections were extracted and used together with LSI IgH (immunoglobulin heavy chain) (spectrum green)/bcl-2(B-cell leukemia-lymphoma 2) (spectrum orange) probes. RESULTS: The DNA and nuclei isolation success rate for B5 formalin-fixed, paraffin-embedded tissue sections (n = 12)was 42% and 33%, respectively, versus 95% and 60%, respectively, for 20 tissue sections fixed in formalin only. In all,24 paraffin-embedded tissue sections were analyzed and mbr positivity was observed in the DNA of 82.14% via seminested PCR, in 53.57% via multiplex PCR, and in 28.57% via real-time PCR. We did not detect mcr rearrangementin any of the samples. In all, 15 of 16 patients (93.75%) whose nuclei were successfully isolated were observed to bet(14;18) positive via the FISH method. CONCLUSION: Semi-nested PCR and FISH facilitated the genetic characterization of FL tumors. As such, FISH and PCR complement each other and are both essential for detecting t(14;18) translocation.