Publication details

Impact of BCR::ABL1 transcript type on RT-qPCR amplification performance and molecular response to therapy

Authors	SALMON M. WHITE H. E. ZIZKOVA Hana GOTTSCHALK A. MOTLOVA Eliska CERVEIRA N. COLOMER D. CORIU D. FRANKE G. N. GOTTARDI E. IZZO B. JURČEK Tomáš LION T. SCHAFER V. VENTURI C. VIGNERI P. ZAWADA M. ZUNA Jan HOVORKOVA Lenka KOBLIHOVA Jitka KLAMOVA Hana MARKOVA STASTNA Marketa SRBOVA Dana BENESOVA Adela POLIVKOVA Vaclava ŽÁČKOVÁ Daniela MAYER Jiří ROEDER I. GLAUCHE I. ERNST T. HOCHHAUS A. POLAKOVA K. M. CROSS N. C. P.
Year of publication	2022
Type	Article in Periodical
Magazine / Source	Leukemia
MU Faculty or unit	Faculty of Medicine
Citation
web	https://www.nature.com/articles/s41375-022-01612-2
Doi	http://dx.doi.org/10.1038/s41375-022-01612-2
Keywords	Cancer genetics; Myeloproliferative disease
Description	Several studies have reported that chronic myeloid leukaemia (CML) patients expressing e14a2 BCR::ABL1 have a faster molecular response to therapy compared to patients expressing e13a2. To explore the reason for this difference we undertook a detailed technical comparison of the commonly used Europe Against Cancer (EAC) BCR::ABL1 reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) assay in European Treatment and Outcome Study (EUTOS) reference laboratories (n = 10). We found the amplification ratio of the e13a2 amplicon was 38% greater than e14a2 (p = 0.015), and the amplification efficiency was 2% greater (P = 0.17). This subtle difference led to measurable transcript-type dependent variation in estimates of residual disease which could be corrected by (i) taking the qPCR amplification efficiency into account, (ii) using alternative RT-qPCR approaches or (iii) droplet digital PCR (ddPCR), a technique which is relatively insensitive to differences in amplification kinetics. In CML patients, higher levels of BCR::ABL1/GUSB were identified at diagnosis for patients expressing e13a2 (n = 67) compared to e14a2 (n = 78) when analysed by RT-qPCR (P = 0.0005) but not ddPCR (P = 0.5). These data indicate that widely used RT-qPCR assays result in subtly different estimates of disease depending on BCR::ABL1 transcript type; these differences are small but may need to be considered for optimal patient management.