Browsing by Subject "CML"
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(2016)Chronic myeloid leukemia (CML) is a malignant hematologic disorder, which is fatal without a treatment. Oral tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of CML and transformed the disease to a chronic condition that can be treated at patient's home. The common problem in the treatment of CML is patient's poor adherence to TKIs. The regular, consistent use of TKIs is crucial to keep disease under control. For this reason and to obtain an optimal treatment outcome, adherence to TKIs is extremely important. The aim of the study was to assess reasons for poor adherence to TKI-medications in Finnish CMLpatients, including patient characteristics, treatment related factors, comorbidities and concomitant medications. In addition, patients' experiences, beliefs, knowledge and perception about CML and its treatment were explored and how these could contribute to nonadherent behaviour. This study is part of the larger study, assessing adherence to TKI treatment among Finnish CML population. The data was obtained by using patient questionnaires and semi-structured theme-interview during patient meetings in 2012. Study population consisted of Finnish adult CML patients who had been on TKI -medication (imatinib, nilotinib or dasatinib) for more than six months prior to the study baseline. Patients' adherence was measured using Morisky Medication Adherence 8-Item Scale (MMAS-8) and based on their score, patients were divided into three groups: high, medium and low adherence. Both quantitative and qualitative methods were used in data analysis. Study findings show that 21% (n=18) of the patients were low adherent and 23% (n=20) were high adherent to their treatment. Patient sociodemographic characteristics or experienced adverse drug reactions (ADRs) did not predict adherence, while more concomitant medications and comorbidities were associated with high adherence. However, ADRs had negative effect on the quality of life of several nonadherent patients. All nonadherent patients reported unintentional nonadherence and the most common reason was forgetting. Two-thirds of the patients (n=12) reported intentional nonadherence, which often was a result of experienced ADRs. The knowledge of CML and its treatment was poor among all patients while over half of the nonadherent patients (n=11) thought that they received enough information received. Overall, patients were very satisfied with care provided by the hospitals, physicians and other healthcare professionals. Managing TKI-treatment regimen is challenging for many patients and ADRs can have a negative impact on the quality of life. Healthcare professionals should regularly assess patient adherence and provide information and support for the patients to help them to succeed in medication management. Reasons for poor adherence are complex and have to be identified from each individual patient so that adherence can be improved.
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(2015)Given the success of first-line treatment in chronic myeloid leukemia (CML), the prevalence of the disease is estimated to increase and more patients are expected to develop resistance to therapy. Thus, even relatively rare point mutations are likely to become more common. In CML, the uncontrollable division of myeloid cells is caused by a reciprocal translocation of chromosomes 9 and 22, resulting in the Philadelphia chromosome. At the meeting point of the two chromosomes, breakpoint cluster region (BCR) and Abelson proto-oncogene 1 (ABL1) fuse together to form the chimeric fusion oncogene BCR-ABL1, the latter of which, the non-receptor tyrosine kinase ABL1, is the driver of the disease. Since the tyrosine kinase inhibitor (TKI) imatinib became available in 2001, the success of first-line therapy has significantly improved the prognosis of CML patients. However, up to 50% of patients with imatinib-refractory disease develop resistance due to point mutations in ABL1, and the most common mutation to emerge is BCR-ABL1 T315I. The broad-range TKI ponatinib is the only approved TKI that inhibits the kinase activity of BCR-ABL1 T315I, but adverse side effects leave patients with this mutation in need of a better, safer, and more effective treatment. The kinase inhibitor axitinib was shown to be selective for BCR-ABL1 T315I, but mutations that emerge as a consequence of axitinib-resistance have yet to be explored. Moreover, patients with the T315I mutation treated with ponatinib have been reported to develop highly drug-resistant mutations in BCR-ABL1 such as T315M and the E255V/T315I compound mutation. The purpose of this study was to identify mutations that enable cells to develop resistance to the kinase inhibitor axitinib and to find new, potential inhibitors for cells expressing the drug-resistant mutations BCR-ABL1 T315I, BCR-ABL1 T315M, and BCR-ABL1 E255V/T315I. To this end, mouse hematopoietic cell lines were constructed prior to determining cell viability in response to inhibitors in combinations and as independent agents. As a novel finding, cells stably expressing T315M were found to exhibit sensitivity to inhibitors of topoisomerase II and mTOR. Moreover, synthetic lethality occurred in these cells in response to the combined treatment of the allosteric inhibitor asciminib and the TKI ponatinib, although not in clinically relevant doses. The highly resistant cells expressing BCR-ABL1 E255V/T315I, like cells expressing T315I and T315M, showed sensitivity to conventional chemotherapy. Notably, however, three SMAC mimetics displayed selectivity to cells expressing BCR-ABL1 E255V/T315I over cells expressing only the single T315I mutation. Considering that CML is expected to become increasingly prevalent, more patients are estimated to develop resistance to therapy. As even relatively rare mutations in BCR-ABL1 become more common, finding an effective treatment for cells expressing these highly resistant mutations takes us one step closer to identifying a safe and effective treatment for CML patients carrying those mutations.
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(2015)Given the success of first-line treatment in chronic myeloid leukemia (CML), the prevalence of the disease is estimated to increase and more patients are expected to develop resistance to therapy. Thus, even relatively rare point mutations are likely to become more common. In CML, the uncontrollable division of myeloid cells is caused by a reciprocal translocation of chromosomes 9 and 22, resulting in the Philadelphia chromosome. At the meeting point of the two chromosomes, breakpoint cluster region (BCR) and Abelson proto-oncogene 1 (ABL1) fuse together to form the chimeric fusion oncogene BCR-ABL1, the latter of which, the non-receptor tyrosine kinase ABL1, is the driver of the disease. Since the tyrosine kinase inhibitor (TKI) imatinib became available in 2001, the success of first-line therapy has significantly improved the prognosis of CML patients. However, up to 50% of patients with imatinib-refractory disease develop resistance due to point mutations in ABL1, and the most common mutation to emerge is BCR-ABL1 T315I. The broad-range TKI ponatinib is the only approved TKI that inhibits the kinase activity of BCR-ABL1 T315I, but adverse side effects leave patients with this mutation in need of a better, safer, and more effective treatment. The kinase inhibitor axitinib was shown to be selective for BCR-ABL1 T315I, but mutations that emerge as a consequence of axitinib-resistance have yet to be explored. Moreover, patients with the T315I mutation treated with ponatinib have been reported to develop highly drug-resistant mutations in BCR-ABL1 such as T315M and the E255V/T315I compound mutation. The purpose of this study was to identify mutations that enable cells to develop resistance to the kinase inhibitor axitinib and to find new, potential inhibitors for cells expressing the drug-resistant mutations BCR-ABL1 T315I, BCR-ABL1 T315M, and BCR-ABL1 E255V/T315I. To this end, mouse hematopoietic cell lines were constructed prior to determining cell viability in response to inhibitors in combinations and as independent agents. As a novel finding, cells stably expressing T315M were found to exhibit sensitivity to inhibitors of topoisomerase II and mTOR. Moreover, synthetic lethality occurred in these cells in response to the combined treatment of the allosteric inhibitor asciminib and the TKI ponatinib, although not in clinically relevant doses. The highly resistant cells expressing BCR-ABL1 E255V/T315I, like cells expressing T315I and T315M, showed sensitivity to conventional chemotherapy. Notably, however, three SMAC mimetics displayed selectivity to cells expressing BCR-ABL1 E255V/T315I over cells expressing only the single T315I mutation. Considering that CML is expected to become increasingly prevalent, more patients are estimated to develop resistance to therapy. As even relatively rare mutations in BCR-ABL1 become more common, finding an effective treatment for cells expressing these highly resistant mutations takes us one step closer to identifying a safe and effective treatment for CML patients carrying those mutations.
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(2016)Tutkielman aiheena oli kroonista myeloista leukemiaa sairastavien potilaiden T-solujen aktiivisuus ja sytokiinituotanto. Potilasmateriaalina oli ns. STOP-tutkimuksen potilaat, joita on seurattu Hematologisessa tutkimusyksikössä vuodesta 2006. STOP- tutkimuksen yhtenä kiinnostuskohteena oli KML-potilaiden mahdollinen paraneminen ja molekylaarisen vasteen säilyminen tyrosiinikinaasi-inhibiittorilääkityksen loputtua. Tässä projektissa vertasin relapsoituneiden potilaiden valkosoluja remission säilyttäneiden potilaiden valkosoluihin. T-solujen aktivaation jälkeen tulokset analysoitiin virtaussytometrialla. Tulosten perusteella vaikuttaa siltä, että remission säilyttäneillä potilailla sytokiinituotanto (IFN-γ ja TNF-α) on voimakkaampaa kuin relapsoituneilla potilailla. Tämä voi osin selittää, miksi remission säilyttäminen on joillain potilailla onnistunut pitkäaikaisesti. Tulokset tulee kuitenkin vahvistaa meneillään olevissa kliinisissä tutkimuksissa, joissa on suurempi potilasmäärä mukana.
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(2016)Tutkielman aiheena oli kroonista myeloista leukemiaa sairastavien potilaiden T-solujen aktiivisuus ja sytokiinituotanto. Potilasmateriaalina oli ns. STOP-tutkimuksen potilaat, joita on seurattu Hematologisessa tutkimusyksikössä vuodesta 2006. STOP- tutkimuksen yhtenä kiinnostuskohteena oli KML-potilaiden mahdollinen paraneminen ja molekylaarisen vasteen säilyminen tyrosiinikinaasi-inhibiittorilääkityksen loputtua. Tässä projektissa vertasin relapsoituneiden potilaiden valkosoluja remission säilyttäneiden potilaiden valkosoluihin. T-solujen aktivaation jälkeen tulokset analysoitiin virtaussytometrialla. Tulosten perusteella vaikuttaa siltä, että remission säilyttäneillä potilailla sytokiinituotanto (IFN-γ ja TNF-α) on voimakkaampaa kuin relapsoituneilla potilailla. Tämä voi osin selittää, miksi remission säilyttäminen on joillain potilailla onnistunut pitkäaikaisesti. Tulokset tulee kuitenkin vahvistaa meneillään olevissa kliinisissä tutkimuksissa, joissa on suurempi potilasmäärä mukana.
Now showing items 1-5 of 5