Project description:Imatinib is a highly effective drug in up-front treatment of chronic myeloid leukemia (CML). In children impaired longitudinal growth has been reported as side effect exerted by this drug under prolonged therapy. We therefore prospectively evaluated alterations of bone biochemical markers in pediatric patients with CML under ongoing imatinib exposure.Bone metabolic markers (calcium, phosphate, magnesium, parathyroid hormone, vitamin D, procollagen type l N propeptide [PINP], and C-terminal cross-linking telopeptide of collagen [CTX-I], osteocalcin [OC]; pyridinoline [PYD], and desoxypyridinoline [DPD]) were determined in 17 patients with CML aged 4-17 years under imatinib treatment in three-month intervals over a 2.5 year period.Hyperparathyroidism developed in 8/17 patients and low 25-hydroxyvitamin-D3 levels were found in 15/17 patients. Increased OC levels were detected in 58% of all specimen showing a linear significant decline of -0.30 µg OC per l per week (p=0.04). Serum PINP was lowered in 25% and serum CTX-I was above the normal range in 57% of the specimen originating exclusively from prepupertal patients. Urine PYD and Urine DPD levels were above the normal range in 10% and 9%, respectively, of all specimen collected and a statistically significant linear decline of -0.16 nmol DPD/mg creatinine/week was calculated (p=0.01).Bone remodeling may be dysregulated by imatinib. Data suggest that impaired bone formation exceeds that of decreased bone resorption. Regular evaluation of the skeletal actions during long-term imatinib treatment in childhood CML is warranted.
Project description:The most frequent BCR-ABL1-p210 transcripts in chronic myeloid leukemia (CML) are e14a2 and e13a2. Imatinib (IM) is the most common first-line tyrosine-kinase inhibitor (TKI) used to treat CML. Some studies suggest that BCR-ABL1 transcript types confer different responses to IM. The objective of this study was to correlate the expression of e14a2 or e13a2 to clinical characteristics, cumulative cytogenetic and molecular responses to IM, acquisition of deep molecular response (DMR) and its duration (sDMR), progression rate (CIP), overall survival (OS), and treatment-free remission (TFR) rate. We studied 202 CML patients, 76 expressing the e13a2 and 126 the e14a2, and correlated the differential transcript expression with the above-mentioned parameters. There were no differences in the cumulative incidence of cytogenetic responses nor in the acquisition of DMR and sDMR between the two groups, but the e14a2 transcript had a positive impact on molecular response during the first 6 months, whereas the e13a2 was associated with improved long-term OS. No correlation was observed between the transcript type and TFR rate.
Project description:An increase in the serum concentration of pancreatic enzymes (amylase and lipase) was reported in a proportion of imatinib-resistant and/or intolerant Philadelphia-positive chronic myeloid leukemia patients treated with nilotinib. Acute pancreatitis was very rare, and the relevance of these laboratory alterations remains unknown. We report on 8 chronic myeloid leukemia patients who developed serum lipase/amylase elevation during treatment with nilotinib. After a median follow-up of 26 months, none of these patients developed an acute pancreatitis or clinical signs of pancreatic disease. Pancreatic hyperenzymemia never led to permanent drug discontinuation and required nilotinib temporary interruption in one case only. The median cumulative duration of dose interruptions and response to treatment were comparable in patients with or without pancreatic enzyme elevation. The mechanisms of action of nilotinib on pancreatic enzymes deserves to be investigated: however, in our experience, the relevance of pancreatic hyperenzymemia was clinically very limited.
Project description:The majority of patients with chronic myeloid leukemia are successfully managed with life-long treatment with tyrosine kinase inhibitors. In patients in chronic phase, other malignancies are among the most common causes of death, raising concerns on the relationship between these deaths and the off-target effects of tyrosine kinase inhibitors. We analyzed the incidence of second primary malignancies, and related mortality, in 514 chronic myeloid leukemia patients enrolled in clinical trials in which imatinib was given as first-line treatment. We then compared the observed incidence and mortality with those expected in the age- and sex-matched Italian general population, calculating standardized incidence and standardized mortality ratios. After a median follow-up of 74 months, 5.8% patients developed second primary malignancies. The median time from chronic myeloid leukemia to diagnosis of the second primary malignancies was 34 months. We did not find a higher incidence of second primary malignancies compared to that in the age- and sex-matched Italian general population, with standardized incidence ratios of 1.06 (95% CI: 0.57-1.54) and 1.61 (95% CI: 0.92-2.31) in males and females, respectively. Overall, 3.1% patients died of second primary malignancies. The death rate in patients with second primary malignancies was 53% (median overall survival: 18 months). Among females, the observed cancer-related mortality was superior to that expected in the age- and sex-matched Italian population, with a standardized mortality ratio of 2.41 (95% CI: 1.26 - 3.56). In conclusion, our analysis of patients with imatinib-treated chronic myeloid leukemia did not reveal a higher incidence of second primary malignancies; however, the outcome of second primary malignancies in such patients was worse than expected. Clinicaltrials.gov: NCT00514488, NCT00510926.
Project description:The development of imatinib for the treatment of chronic myeloid leukemia (CML) has proven to be an example of medical success in the era of targeted therapy. However, imatinib resistance or intolerance occurs in a substantial number of patients. Additionally, patients who have progressed beyond the chronic phase of CML do relatively poorly with imatinib therapy. Mechanisms of imatinib resistance include BCR-ABL point mutations resulting in decreased imatinib binding, as well as mutation-independent causes of resistance such as SRC family kinase dysregulation, BCR-ABL gene amplification, drug influx/efflux mechanisms and other poorly understood processes. The options for therapy in these patients include stem cell transplantation, imatinib dose escalation as well as the use of second-generation tyrosine kinase inhibitors. Dasatinib is a second-generation multi-kinase inhibitor with several theoretical and mechanistic advantages over imatinib. Moreover, several studies have evaluated dasatinib in patients who have progressed on imatinib therapy with encouraging results. Other novel agents such as mTOR inhibitors, bosutinib and INNO 406 have also shown promise in this setting. Although treatment options have increased, the choice of second-line therapy in patients with CML is influenced by concerns surrounding the duration of response as well as toxicity. Consequently, there is no agreed upon optimal second-line agent. This paper reviews the current data and attempts to address these issues.
Project description:Chronic myeloid leukemia (CML) in childhood and adolescence is a rare malignancy that can successfully be treated with the tyrosine kinase inhibitor (TKI) imatinib. According to the current experience, treatment is necessary for years and, in the majority of cases, a lifelong approach is required to control the malignant disease. To what extent imatinib causes immunosuppression in different age cohorts is a controversial discussion. According to general medical recommendations, live vaccines are contraindicated in individuals treated with imatinib. However, a recent increase in the number of globally reported cases of measles has been observed and continues to rise. Due to the high contagiousness of the virus, near-perfect vaccination coverage (herd immunity of 93 to 95%) is required to effectively protect against measles resurgence-a scenario that is not realistic in many countries. When four teenagers with CML (median age 13 years, range 12-15) who were enrolled into pediatric trial CML-paed II while on imatinib treatment (median treatment duration 36 months, range 11-84) were identified without protective measles and/or varicella titers, we carefully balanced the risks of a live vaccination under immunosuppressive TKI medication against the benefit of being protected. The patients underwent live vaccination with the live attenuated vaccines M-M-RVAX Pro® and Varivax® simultaneously (Patient #1), Priorix® and Varilix® consecutively (Patient #2), and Priorix® (Patients #3 and #4). While the first three patients were vaccinated while receiving TKI therapy, treatment with imatinib was interrupted in patient #4 for 1 week prior and 2 weeks after vaccination. Patients #1 and #3 reacted with stable long-term seroconversion. In Patient #2, serum titer conversion against measles and varicella could not be demonstrated and thus revaccination with Priorix® and Varilix® was performed 3 years later. However, protective titers did not develop or were lost again. Patient #4 also lost protective titers against measles when assessed 10 months after vaccination, but revaccination resulted in stable seroprotective titers over 12 months after the last vaccination during ongoing imatinib treatment. We conclude that in all patients, the safety of live vaccines could be documented, as no acute or late adverse events were observed. However, in line with observations that memory B-cells are lost under exposure to imatinib, revaccination may become necessary (two out of four patients in this small series lost their seroprotection). Considering that the number of cases is very small, we also suggest some criteria for decision-making regarding live vaccinations of CML patients treated with imatinib.
Project description:BackgroundAbout 40% of all patients with chronic myeloid leukemia are currently old or very old. They are effectively treated with imatinib, even though underrepresented in clinical studies. Furthermore, as it happens in the general population, they often receive multiple drugs for associated chronic illnesses. Aim of this study was to assess whether or not in imatinib-treated patients aged >75 years the exposure to polypharmacy (5 drugs or more) had an impact on cytogenetic and molecular response rates, event-free and overall survival, as well as on hematological or extra-hematological toxicity.Methods296 patients at 35 Italian hematological institutions were evaluated.ResultsPolypharmacy was reported in 107 patients (36.1%), and drugs more frequently used were antiplatelets, diuretics, proton pump inhibitors, ACE-inhibitors, beta-blockers, calcium channel blockers, angiotensin II receptors blockers, statins, oral hypoglycemic drugs and alpha blockers. Complete cytogenetic response was obtained in 174 patients (58.8%), 78 (26.4%) within 6 month, 63 (21.3%) between 7 and 12 months. Major molecular response was obtained in 153 patients (51.7%), 64 (21.6%) within the 12 month. One hundred and twenty-eight cases (43.2%) of hematological toxicity were recorded, together with 167 cases (56.4%) of extra-hematological toxicity. Comparing patients exposed to polypharmacy to those without, no difference was observed pertaining to the dosage of imatinib, cytogenetic and molecular responses and hematological and extra-hematological toxicity.ConclusionNotwithstanding the several interactions reported in the literature between imatinib and some of the medications considered herewith, this fact does not seem to have a clinical impact on response rate and outcome.
Project description:Hyaluronan (HA) is the main glycosaminoglycan of the extracellular matrix. CD44 is the most important HA receptor, and both have been associated with poor prognosis in cancer. Chronic myeloid leukemia (CML) is characterized by the presence of a constitutively activated tyrosine kinase (Breakpoint Cluster Region - Abelson murine leukemia viral oncogene homolog1, BCR-ABL). It is mainly treated with BCR-ABL inhibitors, such as imatinib. However, the selection of resistant cells leads to treatment failure. The aim of this work was to determine the capacity of HA (high molecular weight) to counteract the effect of imatinib in human CML cell lines (K562 and Kv562). We demonstrated that imatinib decreased HA levels and the surface expression of CD44 in both cell lines. Furthermore, HA abrogated the anti-proliferative and pro-senescent effect of Imatinib without modifying the imatinib-induced apoptosis. Moreover, the inhibition of HA synthesis with 4-methylumbelliferone enhanced the anti-proliferative effect of imatinib. These results suggest that Imatinib-induced senescence would depend on the reduction in HA levels, describing, for the first time, the role of HA in the development of resistance to imatinib. These findings show that low levels of HA are crucial for an effective therapy with imatinib in CML.
Project description:BackgroundMammalian cells contain three functional RAS proto-oncogenes, known as H-RAS, K-RAS, and N-RAS, which encode small GTP-binding proteins in terms of p21rass. RAS genes have been elucidated as major participants in the development and progression of cancer. A single nucleotide polymorphism (SNP) at H-RAS cDNA position 81 T→C (rs12628) has been found to be associated with the risk of many human cancers like gastrointestinal, oral, colon, bladder and thyroid carcinomas. Therefore, we hypothesized that this polymorphisms in H-RAS could influence susceptibility to chronic myeloid leukemia as well, and we conducted this study to test the hypothesis in Indian population.MethodH-RAS polymorphism was studied in 100 chronic myeloid leukemia (CML) patients and 100 healthy controls by restriction fragmentation length polymorphism (RFLP-PCR). Associations between polymorphism and clinicopathological features of CML patients were investigated.ResultsIn CML patients, the TT, TC and CC genotype frequency was 38%, 61% and 1% respectively, compared to 92%, 8% and 0% in healthy controls respectively. Compared to TT genotype, CT was significantly associated with increased risk of CML (odds ratio (OR): 8.4, P < 0.00001). There was a statistically significant correlation of H-RAS polymorphism with phases (P < 0.0003), molecular response (P < 0.0001), hematological response (P < 0.04) and thrombocytopenia (P < 0.003). However, there was no correlation of this polymorphism found with other clinical parameters.ConclusionH-RAS T81C polymorphism was found to be associated with CML risk and prognosis of CML. These results suggest that C heterozygosis may be considered a potential risk factor for CML development in the North Indian population.
Project description:Introduction:Skp2 is an E3 ubiquitin ligase that plays an important role in modulating tumor progression. The mechanisms underlying Skp2 in the promotion of proliferation and its function in the primary resistance to tyrosine kinase inhibitors (TKIs) in human CML remain to be determined. This study aimed to investigate the function of Skp2 in CML progression as well as its effects on TKI sensitivity. Methods:Expression of Skp2 in leukocytes from patients with CML and normal blood samples was analyzed by qRT-PCR. Cell proliferation was analyzed by EdU incorporation and cell counting assays. Luciferase reporter and chromatin immunoprecipitation assays were used for examination of the effects of CREB on Skp2 expression. The apoptosis in vitro of K562 cells was analyzed by MTT and caspase 3/7 activity assays. Results:The present study demonstrates that Skp2 was expressed at a higher level in patients with CML compared with healthy donors, and the elevated expression of Skp2 is critical for CML cell proliferation. Mechanistically, Skp2 was transcriptionally upregulated by CREB responsive to the PI3K/Akt signaling pathway. Furthermore, inhibition of Skp2 expression by shRNAs or blocking the PI3K/Akt/CREB pathway greatly enhances the sensitivity of CML cells to Imatinib treatment. Conclusion:We conclude that the PI3K/Akt/CREB axis regulates the sensitivity of K562 cells to Imatinib via mediating Skp2 expression. The present study revealed an unknown role of Skp2 in CML progression and provided new aspects on the Skp2-modulated TKI sensitivity in CML, contributing to the development of potential therapeutic anticancer drugs.