Low Level of TERC Gene Amplification between Chronic Myeloid Leukaemia Patients Resistant and Respond to Imatinib Mesylate Treatment

  • Mohamad Ashari, Zaidatul Shakila (Human Genome Center, School of Medical Sciences, Health Campus, Universiti Sains Malaysia) ;
  • Sulong, Sarina (Human Genome Center, School of Medical Sciences, Health Campus, Universiti Sains Malaysia) ;
  • Hassan, Rosline (Department of Haematology, School of Medical Sciences, Health Campus, Universiti Sains Malaysia) ;
  • Husin, Azlan (Haemato-Oncology Unit, Department of Internal Medicine, School of Medical Sciences, Health Campus, Universiti Sains Malaysia) ;
  • Sim, Goh Ai (Hospital Pulau Pinang) ;
  • Wahid, S. Fadilah Abdul (Department of Medicine & Cell Therapy Center, Universiti Kebangsaan Malaysia Medical Center)
  • Published : 2014.02.28


The amplification of telomerase component (TERC) gene could play an important role in generation and treatment of haematological malignancies. This present study was aimed to investigate copy number amplification status of TERC gene in chronic myeloid leukaemia (CML) patients who were being treated with imatinib mesylate (IM). Genomic DNA was extracted from peripheral blood of CML-IM Resistant (n=63), CML-IM Respond (n=63) and healthy individuals (n=30). TERC gene copy number predicted (CNP) and copy number calculated (CNC) were determined based on $Taqman^{(R)}$ Copy Number Assay. Fluorescence in situ hybridization (FISH) analysis was performed to confirm the normal signal pattern in C4 (calibrator) for TERC gene. Nine of CML patients showed TERC gene amplification (CNP=3), others had 2 CNP. A total of 17 CML patients expressed CNC>2.31 and the rest had 2.31>CNC>1.5. TERC gene CNP value in healthy individuals was 2 and their CNC value showed in range 1.59-2.31. The average CNC TERC gene copy number was 2.07, 1.99 and 1.94 in CML-IM Resistant patients, CML-IM Respond and healthy groups, respectively. No significant difference of TERC gene amplification observed between CML-IM Resistant and CML-IM Respond patients. Low levels of TERC gene amplification might not have a huge impact in haematological disorders especially in terms of resistance towards IM treatment.


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