Nicolini F.,E Herriot Hospital |
Nicolini F.,French Intergroup of CML Fi LMC Group |
Chomel J.-C.,French Intergroup of CML Fi LMC Group |
Chomel J.-C.,University of Poitiers |
And 15 more authors.
Clinical Lymphoma, Myeloma and Leukemia | Year: 2010
Purpose: The onset of a BCR-ABLT315I mutation during the course of chronic myelogenous leukemia (CML) on tyrosine kinase inhibitors (TKIs) usually results in poor survival, and therapeutic options remain few in the absence of any allogeneic donor. Patients and Methods: We have investigated the affect of subcutaneous omacetaxine (OMA, or homo-harringtonine) cycles on unmutated and T315I-mutated BCR-ABL transcripts in a series of 8 TKI-resistant chronic-phase CML patients and we have addressed the question of whether the administration of OMA could resensitize patients to TKIs. Patients were regularly monitored for total disease burden and for BCR-ABLT315I transcripts using a new quantitative sensitive technique (sensitivity threshold, 0.05%), for up to 27 cycles of OMA. Results: Overall, patients demonstrated hematologic, cytogenetic, or molecular improvement. An initial rapid decline and a sustained disappearance of T315I-mutated transcripts were observed in 50% of patients, after a median of 10.5 cycles (range, 3-27 cycles) of OMA. As the unmutated leukemic burden reduction was modest, 2 patients were submitted to nilotinib after 9 months of sustained BCR-ABLT315I transcripts negativity on OMA and mutated transcripts remained undetectable after a median follow-up of 12 months on nilotinib challenge. Conclusion: We suggest that OMA (ie, a non-targeted therapy) might provide a better disease control allowing the disappearance of the mutated clone probably elicited by the clone deselection after TKI release, and/or a preferential activity of OMA on the T315I-mutated cells through unknown mechanisms. These observations suggest that OMA could allow a safe TKI rechallenge in patients with resistant chronic-phase CML.
Hayette S.,French National Center for Scientific Research |
Hayette S.,French Intergroup of CML Fi LMC Group |
Chabane K.,French National Center for Scientific Research |
Michallet M.,Hopital Edouard Herriot |
And 8 more authors.
Leukemia Research | Year: 2011
This report aims to more accurately define the frequency of the involvement of SRC Family Kinases (SFKs) in imatinib- and dasatinib-resistant CML patients. Clinical samples were analysed during in vivo treatment. We confirmed the high frequency of SFKs involvement in Tyrosine kinase inhibitor-resistant CML (52% of the cases) and even further in progressive disease and blast crises (60% of the cases). The SFKs deregulation is also observed in patients harboring BCR-ABL mutations. In T315I and F317L mutated patients, CML-resistance appears to be promoted by SFKs kinase protein reactivation once the BCR-ABL mutated clone has decreased on Omacetaxine. © 2010 Elsevier Ltd.