ABSTRACT
Chronic myelogenous leukemia [CML] is a kind of hematopoietic stem-cell cancer. A significant number of CML patients who do not achieve an acceptable response to therapy, show acquired resistance against Imatinib. One of the most considerable causes of resistance against Imatinib as the first line of therapy, are BCR-ABL kinase domain mutations. One of the most considerable causes of resistance against Imatinib as the first line of therapy, are BCR-ABL kinase domain mutations. The study was performed on 39 CML patients with Imatinib resistance. Basic hematologic parameters in blood samples were checked to identify hematologic response. To identify molecular response, BCR-ABL/ABL ratio was assessed by Real-time PCR. The ABL kinase domain amplification was performed by PCR. Restriction fragment length polymorphism [RFLP] was performed to detect four common mutations [T315I, Y253H, E255K and M351T]. Finally the results were approved by direct sequencing. In this study, the Y253H mutation, detected by RFLP method and confirmed by direct sequencing, was the prevalent ABL kinase domain mutation in these 39 CML patients. The G250E, V379I and L384M mutations were found in three different cases with failure molecular response. CML patients with these four ABL kinase domain mutations cannot achieve major molecular response [MMR]. In addition, complete hematologic response [CHR] was observed only in the V379I mutated case and not in other mutated patients. Identification of ABL kinase domain mutations may be used as a proper and useful method for improving therapeutic strategies, avoiding delay in treatment and excessive expenditure in CML patients with Imatinib resistance
ABSTRACT
Background: There is an international consensus that evaluation of MYCNamplification should be done in all cases of newly diagnosed neuroblastoma. MYCN is the most important prognostic factor for neuroblastoma and determines treatment strategy
Materials and methods: In this study we evaluated paraffin embedded tissue block and bone marrow aspiration of 75 neuroblastoma patients with mean age of 4.1 years, including 32 female and 43 male, by conventional and also real time quantitative PCR
Results: Forty eight and 43 percent were MYCN amplification positive by Real time and conventional PCR, respectively. 28% of patients less than one year old and 48% of patients older than one year showed MYCN amplification.50 percent of cases with pathological diagnosis of small round cell tumor had MYCN amplification
Conclusion: PCR is a fast, reliable and cost effective method for the evaluation of MYCN amplification and can be performed using DNA extracted from small tissue samples and paraffin embedded blocks. As expected regarding detection power and convenience, Real time PCR was superior to conventional PCR
ABSTRACT
Detection of JAK2V617F mutation was widely used in the diagnosis and classification of myeloproliferative neoplasms. In this study, frequency of JAK2V617F mutation among Iranian patients with polycythemia vera [PV], essential thrombocythemia [ET] and primary myelofibrosis [PMF] was studied. In this basic study, blood samples of 174 patients with polycythemia vera [n=57], essential thrombocythemia [n=84] and primary myelofibrosis [n=33] were evaluated for JAK2V617F mutation. Genomic DNA was extracted from peripheral blood. After quality control of extracted DNA, the JAK2-V617F mutation was analyzed using allele-specific PCR. All PCR products were analyzed by polyacrylamide gel [5%] electrophoresis and silver staining. One hundred and eleven out of 174 patients [63.8%] were positive for the presence of the JAK2V617F mutation. Frequency of mutation was 82% [47/57] in PV, 57% [48/84] in ET and 48% [16/33] in PMF. This study showed that detection of JAK2-V617F mutation using allele-specific PCR lead to better diagnosis and treatment of Iranian patients with different MPNs