The evaluation of t(12;21) TEL-AML1 translocation in acute lymphoblastic leukemia patients by real-time qRT-PCR with 5-year follow-up results
Nur Selvi Günel1, Burçin Tezcanlı Kaymaz1, Vildan Bozok Çetintaş1, Aslı Tetik Vardarlı1, Sunde Yılmaz Süslüer1, Duygu Aygüneş1, Ayegül Dalmizrak1, Çağdaş Aktan1, Ali Şahin Küçükaslan1, Tuğçe Balcı1, Çağla Kayabaşı1, Besra Özmen Yelken1, Çığır Biray Avcı1, Buket Kosova1, Zuhal Eroğlu1, Serap Aksoylar2, Nazan Çetingül2, Can Balkan3, Deniz Yılmaz3, Yeşim Aydınok3, Kaan Kavaklı3, Mahmut Töbü4, Murat Tombuloğlu4, Filiz Büyükkeçeci4, Fahri Şahin4, Güray Saydam4, Cumhur Gündüz1
1Ege Üniversitesi Tıp Fakültesi, Tıbbi Biyoloji Anabilim Dalı, İzmir, Türkiye
2Ege Üniversitesi Tıp Fakültesi, Çocuk Onkoloji Bilim Dalı, İzmir, Türkiye
3Ege Üniversitesi Tıp Fakültesi, Çocuk Hematoloji Bilim Dalı, İzmir, Türkiye
4Ege Üniversitesi Tıp Fakültesi, Hematoloji Bilim Dalı, İzmir, Türkiye
Keywords: Acute lymphoblastic leukemia; polymerase chain reaction; reverse transcriptase.
Objectives: This study aims to quantify the t(12;21) translocation in cases pre-diagnosed with acute lymphoblastic leukemia (ALL) using the real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) method.
Patients and methods: Between January 2009 and December 2013, results of RNA t(12;22) (p13;q22) translocation belonging to blood and bone marrow samples of 175 pediatric and 138 adults, a total of 313 patients, who were admitted to the Department of Medical Biology, Faculty of Medicine, Ege University, were evaluated in this study. Total RNA or messenger RNA isolation was performed for 75 peripheral and 484 bone marrow samples belonging to the cases. Following the RNA isolation, we carried out the complementary DNA synthesis. We performed t(12;21) (p13;q22) translocation appropriate to the primer and probes (Way2Gene) specifically designed for the fusion transcripts by using LightCycler t(12;21) Kit. As the final step, we carried out quantitative evaluations of t(12;21) translocation results via the real-time qRT-PCR method of LightCycler2.
Results: We found 34 pediatric cases (19%) and 17 adults cases (12%) TEL-AML-1 (ETV6-RUNX1) positive. While the average of TEL-AML1 (ETV6-RUNX1) quantification value was 0.90±3.21 for pediatric cases, it was 0.34±1.20 for adult cases.
Conclusion: Our findings support that quantitative assessment of t(12;21) translocation by real-time qRT-PCR method is a valuable one to lead the treatment towards confirming the diagnosis and achieving the molecular remissions in ALL patients during the new diagnostic period and treatment period.