Peripheral Blood Cell mRNA Research Articles

#2009 FGF23 in patients with diabetic kidney disease and atherosclerosis

Abstract Background and Aims Diabetes mellitus (DM) and chronic kidney disease (CKD) are risk factors for vascular atherosclerosis, a pathological process with an important inflammatory component. The coexistence of these conditions in patients with diabetic kidney disease (DKD) has additive effects with worst cardiovascular mortality and morbidity rates when compared to non-diabetic CKD patient on cardiovascular outcomes. Accumulating research has shown that increased levels of bone-derived fibroblast growth factor 23 (FGF23), the major phosphate-regulating hormone, constitute a novel predictor of cardiovascular and all-cause mortality in CKD patients, with potential effects on disorders of glucose metabolism as well. The objective of this comparative study is to determine the differences in FGF23 levels in two groups of patients with CKD, with and without DM, matched by age, sex and renal function, all of them with clinical atherosclerotic disease. We also evaluated the relationships of FGF23 with several inflammatory markers and parameters of glucose metabolism. Method Sixty-six patients with CKD stages 3-4 (33 of them with DM) and diagnosed with peripheral vascular disease were included in the study. Whole blood and serum samples were obtained from all participants. CRP values, neutrophil/lymphocyte (N/L) ratio, HbA1c (%), fasting glucose, and Triglycerides and glucose (TyG) index, among other parameters, were obtained using standardized routine methods. Circulating levels of the intact form of FGF23, tumor necrosis factor (TNF) α, interleukin (IL) 6, and IL10 were determined by ELISA immunoassays in both groups. We also performed gene expression analysis for these three cytokines in peripheral blood cells (PBCs) using qPCR. Results The mean values of eGFR, ACR and phosphate were 37.6 ± 11.2 ml/min/1.73 m2; 294.1 ± 271.2 mg/g; 3.8 ± 0.82 mg/dL; respectively without differences between patients with and without DM The median circulating FGF23 values were higher in the DM group (51.59 [37.73-89.68] vs. 38.1 [33-54.14] pg/mL; p<0.001). Likewise, patients with DM presented higher levels of TNFα both in serum concentration (1.78 [0.72-2.47] vs. 1.28 [1.01-1.88] pg/mL; p<0.01) as in the expression of mRNA in PBCs (2.1 ± 1.26 vs. 1.87 ± 1.16 a.u.; p<0.05). No differences were observed for IL6 and IL10 levels, nor for CRP concentration or N/L ratio. As expected, fasting glucose, HbA1c and TyG index were higher in the group of subjects with DM. FGF23 was inversely correlated with eGFR (r=−0.435, p<0.0001), while it showed a positive association with ACR (r=0.416, p<0.001) and, interestingly, with proinflammatory cytokines including circulating TNFα (r=0.44, p<0.001), circulating IL6 (r=0.27, p=0.04), and TNF mRNA expression in PBCs (r=0.245, p=0.047). Furthermore, circulating FGF23 was also direct and significantly correlated with HbA1c (r=0.34, p<0.01). Conclusion These results suggest that FGF23 levels are higher in DKD than in non-DM CKD patients with similar renal function. DKD patients also had higher levels of the proinflammatory cytokine TNFα. Our results also show positive correlations of FGF23 with the inflammatory cytokines TNFα and IL6, as well as with HbA1c. Previous studies, shown that elevated TNFα and glucose promote FGF23 production, which may help to explain the higher levels of FGF23 in patients with DM Future studies should clarify whether FGF23 is simply a marker of atherosclerosis disease severity or a contributing factor to this complication in CKD.

Unexplained isolated hyperferritinemia without iron overload.

Although hyperferritinemia may be reflective of elevated total body iron stores, there are conditions in which ferritin levels are disproportionately elevated relative to iron status. Autosomal dominant forms of hyperferritinemia due to mutations in the L-ferritin IRE or in A helix of L-ferritin gene have been described, however cases of isolated hyperferritinemia still remain unsolved. We describe 12 Italian subjects with unexplained isolated hyperferritinemia (UIH). Four probands have affected siblings, but no affected parents or offspring. Sequencing analyses did not identify casual mutations in ferritin gene or IRE regions. These patients had normal levels of intracellular ferritin protein and mRNA in peripheral blood cells excluding pathological ferritin production at transcriptional and post-transcriptional level. In contrast with individuals with benign hyperferritinemia caused by mutations affecting the ferritin A helix, low rather than high glycosylation of serum ferritin was observed in our UIH subjects compared with controls. These findings suggest that subjects with UIH have a previously undescribed form of hyperferritinemia possibly attributable to increased cellular ferritin secretion and/or decreased serum ferritin clearance. The cause remains to be defined and we can only speculate the existence of mutations in gene/s not directly implicated in iron metabolism that could affect ferritin turnover including ferritin secretion.

GW27-e1249 Clinical Significance of Low Expression of Malate Dehydrogenase 1 (MDH1) mRNA in Peripheral Blood Cells of Patients with Coronary Heart Disease

GW27-e1249 Clinical Significance of Low Expression of Malate Dehydrogenase 1 (MDH1) mRNA in Peripheral Blood Cells of Patients with Coronary Heart Disease

Integrated analysis of miRNA and mRNA gene expression microarrays: Influence on platelet reactivity, clopidogrel response and drug-induced toxicity

Genetic and epigenetic variability may influence the efficacy and safety of antiplatelet therapies, including clopidogrel. Therefore, the miRNA-mRNA interactions and drug toxicity were investigated in silico using available microarray data. Expressions profiles of platelet miRNA (GSE59488) from acute coronary syndrome and mRNA in peripheral blood cells (GSE32226) from coronary artery disease patients were used to miRNA-target mRNA integrated analysis by Ingenuity Pathways Analysis 6 software (IPA). Results showed that ST13 mRNA is regulated by hsa-miR-107 (miR-103-3p); BTNL3 and CFD mRNAs are regulated by hsa-miR-4701-3p (miR-1262); SLC7A8 is regulated by hsa-miR-145-5p (miR-145-5p); and SENP5 mRNA is regulated by hsa-miR-15b-5p (miR-16-5p) and hsa-miR-26a-5p (miR-26a-5p). Drug toxicity IPA tool showed that these miRNAs/mRNAs are associated with clopidogrel-related liver and renal injury. In conclusion, these results demonstrate that differential expression of miRNAs in platelets and interactions with their target mRNAs are associated with variability in platelet reactivity, clopidogrel response and drug-induced toxicity.

Expression levels of estrogen receptor α mRNA in peripheral blood cells are an independent biomarker for postmenopausal osteoporosis

BackgroundThe up- and down-regulation of the osteoclastogenesis response depends on the estrogen/estrogen receptor (ER) signaling pathway. Previous reports have shown that the promoter hypermethylation and gene polymorphism of ERα are risks for menopausal osteoporosis. No previous study has evaluated the expression levels of ERα mRNA in menopausal osteoporosis using human subjects. We hypothesized that ERα mRNA expression may show less resistance to postmenopausal osteoporosis. MethodsIn this study, we enrolled 107 women older than 45years without menstruation and classified them into control, osteopenia, and osteoporosis groups depending on their T-scores. The ERα mRNA levels in peripheral blood cells (PBCs) were analyzed via quantitative real-time reverse-transcription polymerase chain reaction (QRT-PCR), and estrogen in the serum was detected via ELISA. ResultsERα mRNA levels in PBCs had a negative correlation with age and a positive correlation with estrogen and BAP in the osteopenia and osteoporosis groups, but not in the control group. Additionally, multivariate analysis showed that older age (>55years), and low ERα mRNA levels in PBLs (≦250.39 copies/μg DNA) were associated with an approximately 9.188-, and 31.25-fold risk of osteoporosis. ConclusionWe conclude that ERα mRNA levels in PBLs could be used as an independent risk factor for postmenopausal osteoporosis. General significanceOur findings suggested that ERα mRNA levels in PBLs may be more important than age and serum estrogen levels.

Peripheral Blood Cell Gene Expression Diagnostic for Identifying Symptomatic Transthyretin Amyloidosis Patients: Male and Female Specific Signatures

Background: Early diagnosis of familial transthyretin (TTR) amyloid diseases remains challenging because of variable disease penetrance. Currently, patients must have an amyloid positive tissue biopsy to be eligible for disease-modifying therapies. Endomyocardial biopsies are typically amyloid positive when cardiomyopathy is suspected, but this disease manifestation is generally diagnosed late. Early diagnosis is often difficult because patients exhibit apparent symptoms of polyneuropathy, but have a negative amyloid biopsy. Thus, there is a pressing need for an additional early diagnostic strategy for TTR-aggregation-associated polyneuropathy and cardiomyopathy.Methods and Findings: Global peripheral blood cell mRNA expression profiles from 263 tafamidis-treated and untreated V30M Familiar Amyloid Neuropathy patients, asymptomatic V30M carriers, and healthy, age- and sex-matched controls without TTR mutations were used to differentiate symptomatic from asymptomatic patients. We demonstrate that blood cell gene expression patterns reveal sex-independent, as well as male- and female-specific inflammatory signatures in symptomatic FAP patients, but not in asymptomatic carriers. These signatures differentiated symptomatic patients from asymptomatic V30M carriers with >80% accuracy. There was a global downregulation of the eIF2 pathway and its associated genes in all symptomatic FAP patients. We also demonstrated that the molecular scores based on these signatures significantly trended toward normalized values in an independent cohort of 46 FAP patients after only 3 months of tafamidis treatment.Conclusions: This study identifies novel molecular signatures that differentiate symptomatic FAP patients from asymptomatic V30M carriers as well as affected males and females. We envision using this approach, initially in parallel with amyloid biopsies, to identify individuals who are asymptomatic gene carriers that may convert to FAP patients. Upon further validation, peripheral blood cell mRNA expression profiling could become an independent early diagnostic. This quantitative gene expression signature for symptomatic FAP could also become a biomarker to demonstrate significant disease-modifying effects of drugs and drug candidates. For example, when new disease modifiers are being evaluated in a FAP clinical trial, such surrogate biomarkers have the potential to provide an objective, quantitative and mechanistic molecular diagnostic of disease response to therapy.

Relative Expression of Toll-Like Receptors 2 and 7 mRNA in Peripheral Blood of Patients With Hepatitis C.

Background:Hepatitis C virus (HCV) is an important human pathogen affecting an estimated 120 – 170 million individuals in the world. Toll-Like receptors (TLRs) are pattern-recognition receptors that recognize pathogen-associated molecular patterns, and stimulate immune responses.Objectives:The aim of this study was to determine the mRNA expression level of TLR2 and TLR7 in HCV-infected patients in comparison with normal controls.Patients and Methods:Nineteen consecutive patients with HCV infection and nineteen sex and age-matched healthy controls were studied in a case-controlled research.Results:Our results showed that the expressions of TLR7 in HCV infected samples were significantly increased in comparison those of the controls (P = 0.02), while the expression of TLR2 was similar between the case and the control group (P = 0.8). There were no associations between the expression levels of TLR2 and TLR7 with HCV viral load and HCV genotypes. Also, there was no association between viral load and genotypes of the virus.Conclusions:Our findings showed that HCV infection could lead to increased expression level of TLR7 mRNA in peripheral blood cells of HCV infected samples. The viral load and genotypes of HCV did not affect the mRNA expression levels of TLR2 and TLR7.

Placenta Growth Factor Is Regulated By Heme-Bound Iron Via Erythroid Krüppel-Like Factor In Erythroid Cells and Is Linked To Iron Status In Vivo In Sickle Cell Disease and Hereditary Hemochromatosis

Iron is a critical element for erythroid development and the function of many proteins, but is toxic in excessive amounts, most often by inducing oxidative stress that may play a role in vasculopathy. We have shown that markers of high iron burden such as serum ferritin have been associated with excessive production of the angiogenic factor placenta growth factor (PlGF), high estimated pulmonary artery pressure and death in adults with sickle cell disease. Enforced PlGF expression in mice promotes high circulating levels of the potent vasoconstrictor endothelin-1 and pulmonary hypertension.We find that heme-bound iron stimulates PlGF gene transcription by Erythroid Krüppel‐like Factor (EKLF). Heme-bound iron (hemin) induces PlGF mRNA in erythroid cells more than 200-fold in a dose-dependent and time-dependent fashion. PlGF mRNA is induced by other complexes of iron, but not iron-free heme or zinc protoporphyrin, suggesting that PlGF induction specifically requires iron. In murine and human cell lines, expression of EKLF developmentally precedes PlGF, and enforced expression of EKLF in human erythroid progenitor cells induces PlGF mRNA. Now we further report that hemin-induced expression of PlGF is abolished in EKLF-deficient mouse erythroid cells but rescued by conditional expression of EKLF. By chromosome immunoprecipitation we find that EKLF binds directly to the PlGF promoter region that contains an EKLF consensus sequence. We find that SCD patients have higher level expression than healthy controls of both EKLF and PlGF mRNA in peripheral blood cells, and expression of the two are correlated with each other (r=0.822, p<0.001).Demonstrating the generalizability of this link of iron overload to PlGF expression, we find that patients with hereditary hemochromatosis have a high plasma level of PlGF, which falls after correction of iron overload by periodic phlebotomy therapy (p=0.018). Reductant N-acetyl cysteine completely blocks hemin induction of PlGF, supporting the participation of oxidant stress response pathways already known to mediate signaling by iron on other promoters such as heme oxygenase-1.Our results for the first time demonstrate a specific mechanistic pathway induced by excess iron that is linked in humans with SCD and in mice to vasculopathy and pulmonary hypertension, suggesting that aggressive use of clinically approved iron chelation drugs should be investigated as adjunctive therapy to reduce the risk of pulmonary hypertension in SCD patients with associated iron overload. Linkage of iron overload in patients without hemolysis or anemia to abnormally high level expression of an angiogenic factor shown to induce pulmonary hypertension suggests a general pathobiological pathway connecting iron and vasculopathy. [Display omitted] [Display omitted] Disclosures:No relevant conflicts of interest to declare.

The alteration of hypoxia inducible factor-1 (HIF-1) and its target genes in mood disorder patients

Recent studies suggest that the dysfunction of neural plasticity is associated with mood disorders. Hypoxia-inducible factor-1 (HIF-1), which is a transcriptional activator of vascular endothelial growth factor (VEGF), activates the cellular response to hypoxia. HIF-1 is ubiquitously expressed in all cells, including peripheral leukocytes. However, little is known about the role of HIF-1 in mood disorder. In the present study, we investigated the mRNA expression levels of HIF-1 (α and β) and its target genes (VEGF, GLUT1, PGK1, PFKFB3, and LDHA) in the peripheral white blood cells of patients with major depressive disorder (MDD) and bipolar disorder (BPD). We found increased expression of HIF- 1α and HIF-1β mRNA, as well as the target genes, VEGF, and PFKFB3 in both MDD and BPD patients in a depressive state compared to healthy control subjects. Furthermore, the mRNA expression levels of GLUT1, PGK1, and LDHA were increased in MDD patients in a depressive state compared to healthy control subjects. We also found increased expression of HIF-1α and LDHA mRNA in MDD patients in a remissive state, whereas the mRNA expression levels of other genes in a remissive state were comparable to those in healthy control subjects. There was no significant difference in mRNA expression levels of the genes examined among patients receiving any type of antidepressant or mood stabilizer. Our data suggest that altered expression of HIF-1 and its target genes mRNA in peripheral blood cells are associated-mainly in a state-dependent manner-with mood disorders (especially with MDD). In addition, altered expression of HIF-1 and its target genes may be associated with the pathophysiology of depression.

Detection on Dynamic Changes of Endothelial Cell Specific Molecule–1 in Acute Rejection After Renal Transplantation

To investigate the value of dynamic monitoring of endothelial cell specific molecule-1 (ESM-1) in diagnosing acute rejection after renal transplantation. ESM-1 expression was observed in peripheral blood circulating endothelial cells and renal allografts after renal transplantation, and was compared to the flow cytometry (FCM) results of urine HLA-DR(+) lymphocytes. In patients with acute rejection, ESM-1 mRNA and protein expression increased significantly (P < .01). Real-time polymerase chain reaction detection of ESM-1 mRNA in peripheral blood cells was more sensitive and specific than FCM detection of urine HLA-DR(+) lymphocytes. Moreover, real-time PCR detection is characterized by convenient sampling and good reproducibility. ESM-1 is a new marker for endothelial cell activation. However, its significance during acute rejection in renal transplantation is still unclear. Our study demonstrates that ESM-1 may reflect the degree of endothelial cell injury in renal allografts, and that it may serve as a highly sensitive and specific marker for acute rejection after renal transplantation.

Characterization of Targets of Plitidepsin In JAK2V617F-Mutated Cells From Myeloproliferative Neoplasms

AbstractAbstract 4093 Background:In a previous study (Verrucci M et al, J. Cell Physiol, 2010, Epub May10) we reported that the cyclic depsipeptide Aplidin®, a potent cytotoxic agent currently in phase II/III clinical trials for solid and hematologic neoplasia, displayed activity in a murine model of myelofibrosis, the GATA1-low mice. In fact, Aplidin improved the proliferation of Gata1-low hematopoietic cells, corrected abnormal microvessel density and reduced bone marrow fibrosis. These effects were largely attributed to improved maturation of megakaryocytes, as suggested by the increased platelet count in thrombocytopenic Gata1-low mice. It has been previously shown that a low expression of p27 in tumor cells might correlate with their response to Aplidin; of interest, GATA1-low megakaryocytes expressed reduced levels of p27. Overall, these results suggested that Aplidin could have the potential to alter the course of myelofibrosis-like disease in Gata1-low mice and could be useful for the treatment of myelofibrosis. Aims:to evaluate activity and targets of Aplidin in cellular models of myeloproliferative neoplasms (MPN). Methods:We measured the effect of Aplidin on the proliferation of JAK2V617F-mutated cell lines (UKE-1, HEL, SET2) and of primary cells from MPN patients in liquid cultures and semisolid medium, the rate of apoptosis using Annexin V flow cytometry analysis, and the cell cycle by propidium iodide staining. Expression of mRNA was quantified by real-time PCR, while protein level was measured by western blotting. Gene expression profiling was accomplished with Agilent Whole Human Genome Oligo Microarrays (44K). Results:Aplidin reduced the proliferation of all human V617F-mutated cell lines in the low nanomolar range, with IC50 from 0.5+/−0.03nM for UKE-1 to 1.5+/−0.05nM for HEL cells. Aplidin increased the proportion of cells in the G1/G0 phase of cell cycle, up to a mean of 80+/−5% from 60+/−3% in control cells (P<0.01). Also the proportion of apoptotic cells dose-dependently increased from 20+/−3% in control cultures to 50+/−6% at 10 nM in UKE-1 cells. After 24 h of incubation with Aplidin, the level of p27 mRNA was dose-dependently increased in all cell lines evaluated, while the BCR/ABL mutated K562 cells, whose proliferative rate was inhibited at higher Aplidin concentration, did not show significant changes of p27 mRNA. By western blotting analysis, level of p27 was overtly increased in UKE-1 cells treated with 5 and 10 nM Aplidin for 24h, and at the highest concentration we also observed reduction of phosphorylated STAT5. On the other hand, there was no change in JAK2, pJAK2, STAT5, STAT3, pSTAT3, Akt, pAkt. We then measured the level of p27 mRNA in peripheral blood cells obtained from patients with polycythemia vera (PV) or primary myelofibrosis (PMF). We found that PMF patients had significantly reduced p27 mRNA and protein level compared to controls and PV patients (P<.001 for both). After incubation with 1nM Aplidin there was a 2.5+/−2.0-fold increase in the p27 mRNA level and protein in cells of PMF patients while it was substantially unaffected in controls or PV patients. Gene expression analysis was performed in SET2 and UKE-1 cells that had been treated with 3nM of Aplidin for 24 hr. Aplidin treatment of SET2 cell line resulted in the up-regulation (UR) of 268 probsets and down-regulation (DR) of 247 (in total, about 1.5% of 40,961 genes called as “present”); corresponding figures in UKE-1 cells were 261 for UR (0.6%) and 364 (0.9%) for DR genes. MAPK signalling, TGF-beta signaling pathway, Cytokine-cytokine receptor interaction, cell adhesion molecules (CAMs), neuroactive ligand-receptor interaction, T cell receptor signaling, calcium signaling pathway, and regulation of actin cytoskeleton were the most involved pathways. Conclusions:Current results suggest that Aplidin has growth inhibitory activity and induces apoptosis in MPN cells. Response to Aplidin involves increasing p27 level, similar to findings in myelofibrotic GATA1-low mice; furthermore, we have identified low p27 expression as a characteristic of PMF cells compared to normal and PV cells. Finally, gene expression analysis allowed to identify a set of genes and involved pathways undergoing differential regulation in response to Aplidin. These information could be of value also for analyzing the response to Aplidin of PMF patients enrolled in an ongoing Phase II clinical trial. Disclosures:Aracil:PharmaMar: Employment. Vannucchi:PharmaMar: Research Funding.

Glyoxalase-I mRNA expression and CCK-4 induced panic attacks

Rationale There is evidence that the anti-glycation enzyme glyoxalase-1 (GLO1) may play a role in anxiety-related behaviour. However, discordant findings between GLO1 expression and anxiety-related behaviour have been observed in animal models. Because no data are available on the relation between GLO1 mRNA expression and human anxiety so far, we investigated the expression of GLO1 mRNA in peripheral blood cells in relation to cholecystokinin-tetrapeptide (CCK-4) induced panic anxiety in healthy subjects as an established model of human anxiety in healthy volunteers. Methods Twenty-three healthy subjects underwent challenge with CCK-4. GLO1 mRNA expression was assessed by quantitative real-time polymerase chain reaction prior to CCK-4 injection. Baseline anxiety was assessed with the State-Trait-Anxiety-Inventory (STAI) and panic response was measured with the Panic Symptom Scale (PSS). Results CCK-4 elicited a marked anxiety response accompanied by a significant increase in heart rate. GLO1 mRNA expression did not correlate with state or trait anxiety nor with severity of CCK-4 induced anxiety. Conclusions The lack of correlation between GLO1 mRNA expression and CCK-4 induced panic severity suggests that GLO1 is not involved into the acute panic response to CCK-4 in healthy volunteers. Therefore, further studies are needed to clarify the involvement of GLO1 in anxiety disorders at baseline and in anxiety challenge paradigms to resolve the apparent contradictions of preclinical studies concerning the relationship between GLO1 expression and anxiety.

Noninvasive diagnosis of acute rejection of renal allografts

Acute rejection is an immune process that begins with the recognition of the allograft as nonself and ends in graft destruction. Histological features of the allograft biopsy are currently used for the differential diagnosis of allograft dysfunction. In view of the safety and the opportunity for repetitive sampling, development of noninvasive biomarkers of allograft status is an important objective in transplantation. Herein, we review some of the progress towards the development of noninvasive biomarkers of human allograft status. Urinary cell and peripheral blood cell mRNA profiles have been associated with acute rejection of human renal allografts. Emerging data support the idea that development of noninvasive biomarkers predictive of antibody-mediated rejection is feasible. The demonstration that intragraft microRNA expression predicts renal allograft status suggests that noninvasively ascertained microRNA profiles may be of value. We are pleased with the progress to date, and anticipate clinical trials investigating the hypotheses that noninvasively ascertained mRNA profiles will minimize the need for invasive biopsy procedures, predict the development of acute rejection and chronic allograft nephropathy, facilitate preemptive therapy capable of preserving graft function, and facilitate personalization of immunosuppressive therapy for the allograft recipient.

Dasatinib Efficacy in Patients with Chronic Myeloid Leukemia in Chronic Phase (CML-CP) and Pre-Existing BCR-ABL Mutations

Dasatinib (SPRYCEL®) is an effective BCR-ABL inhibitor that is 325-fold more potent than imatinib and 16-fold more potent than nilotinib in vitro against unmutated BCR-ABL. Across a series of phase II and III trials, dasatinib has demonstrated durable efficacy in patients with CML following resistance, suboptimal response, or intolerance to imatinib. BCR-ABL mutations are an important cause of imatinib failure and suboptimal response. Here, the efficacy of dasatinib in patients with CML-CP who had baseline BCR-ABL mutations following imatinib treatment was analyzed using data from three trials (CA180-013, -017, and -034). Mutational assessment of the BCR-ABL kinase domain was performed using RT-PCR and direct sequencing of peripheral blood cell mRNA. Hematologic, cytogenetic, and molecular response rates were reported after ≥24 mos of follow-up. Duration of response, progression-free survival (PFS), and overall survival (OS; in 013/034) were calculated using Kaplan-Meier analysis, and rates were estimated at the 24-mo time point. Of 1,150 patients with CML-CP who received dasatinib, 1,043 had a baseline mutational assessment and were analyzed further. Of these, 402 patients (39%) had a BCR-ABL mutation, including 8% of 238 imatinib-intolerant and 48% of 805 imatinib-resistant patients. Excluding known polymorphisms, 64 different BCR-ABL mutations were detected affecting 49 amino acids, with G250 (n=61), M351 (n=54), M244 (n=46), F359 (n=42), H396 (n=37), Y253 (n=26), and E255 (n=25) most frequently affected. Dasatinib treatment in patients with or without a baseline BCR-ABL mutation, respectively, resulted in high rates of major cytogenetic response (MCyR; 56% vs 65%), complete cytogenetic response (CCyR; 44% vs 56%), major molecular response (MMR; 33% vs 45%); PFS (70% vs 83%), and OS (89% vs 94%) (Table). After 24 mos, CCyRs in patients with or without a BCR-ABL mutation had been maintained by 84% vs 85%, respectively, of those achieving this response. Among patients with mutations who received dasatinib 100 mg once daily, which has a more favorable clinical safety profile, efficacy and durability were similar (MCyR: 55%; CCyR: 41%; MMR: 36%; PFS: 73%; OS: 90%). In general, high response rates and durable responses were observed in patients with different mutation types, including highly imatinib-resistant mutations in amino acids L248, Y253, E255, F359, and H396. When responses were analyzed according to dasatinib cellular IC50 for individual BCR-ABL mutations, dasatinib efficacy was observed in 44 patients who had any of 5 imatinib-resistant mutations with a dasatinib cellular IC50 >3 nM (Q252H, E255K/V, V299L, and F317L, excluding T315I), including MCyR in 34%, CCyR in 25%, MMR in 18%, PFS in 48%, and OS in 81%. Among patients whose mutations had a dasatinib IC50 ≤3 nM (n=254) or unknown IC50 (n=83), responses and durability were comparable to patients with no BCR-ABL mutation. As expected, few patients with a T315I mutation (IC50 >200 nM; n=21) achieved a response. Among 70 patients with >1 mutation, a MCyR was achieved in 53% and a CCyR in 37%. Among patients with mutational analysis at last follow-up (n=162), 42 (26%) retained a BCR-ABL mutation (20 retained a mutation with IC50 >3 nM), 42 (26%) lost a mutation (5 lost a mutation with IC50 >3 nM), and 44 (27%) developed a new mutation (39 developed a mutation with IC50 >3 nM), with some patients counted in more than one category. Overall, this analysis demonstrates that dasatinib has broad efficacy against all BCR-ABL mutations except for T315l. For patients with BCR-ABL mutations, dasatinib treatment is associated with durable responses and favorable long-term outcomes.TableAnalysis by dasatinib IC50No BCR-ABL mutationBCR-ABL mutationBCR-ABL mutation treated with 100 mg QD>3 nM (excl. T315I)3 nM*Unknown IC50**Patients, n641402494425483Response rates (≥24 mos of follow-up), %CHR939090829496MCyR655655345873CCyR564441254754MMR453336183443Median time to MCyR, mos2.82.92.85.72.92.8Median time to CcyR, mos3.05.33.05.75.43.424-mo PFS (95% CI), %83 (79.8–86.5)70 (65.3–75.2)73 (60.1–86.3)48 (31.2–64.7)73 (66.6–78.9)89 (82.3–96.3)24-mo OS (95% CI), %94 (91.4– 95.7)89 (85.1– 92.1)90 (81.2– 98.3)81 (68.8– 93.8)90 (85.8– 94.2)96 (91.2–100)Some patients had >1 mutation. *Excluding patients with a concurrent mutation with dasatinib IC50 >3 nM. **Excluding patients with a concurrent mutation with known dasatinib IC50.

Sleep apnoea: time to consider clock genes

Most, and perhaps all, cells harbour a circadian clock. These clocks regulate hundreds of physiological processes, ranging from body temperature and sleep–wake cycle to serum cortisol and melatonin concentration. All clocks operate using a very similar molecular mechanism; they communicate with each other through a complex and still poorly understood neuroendocrine network 1. In the mammalian brain, for example, a key clock gene known as Bmal is turned on and off in a 24-h rhythm, not only in the suprachiasmatic nucleus of the hypothalamus (the seat of the master clock) but also in the hippocampus and neocortex 1. It is therefore expected that many processes occurring in the neocortex are subject to clock control. The question, then, is how such control is achieved and which neuoendocrine regulators play a role. The study by Burioka et al. 2 presented in the current issue of the European Respiratory Journal ( ERJ ) contributes significantly towards addressing this question. The circadian rhythm of vigilance, blood pressure, sympathetic activity, corticoid biogenesis and metabolism is severely altered in patients with obstructive sleep apnoea (OSA). Given the previously sketched importance of clock genes in the genesis of circadian rhythm, investigation of circadian gene activation in OSA patients seems to hold promise. Burioka et al. 2 have quantified the expression of the clock gene Per1 mRNA in peripheral blood cells using real-time PCR analysis at different points over 24 h. In contrast to the matched …

Plasma RNA as an alternative to cells for monitoring molecular response in patients with chronic myeloid leukemia

Quantitation of BCR-ABL mRNA is emerging as the standard of care to monitor the status of chronic myeloid leukemia (CML). Peripheral blood plasma was analyzed in this study because of previous detection of nucleic acids and proteins from tumor cells in plasma samples. Reverse transcriptase polyemrase chain reaction was used to establish ratios of BCR-ABL:ABL mRNA in peripheral blood cells and plasma, and absolute levels of BCR-ABL mRNA per unit volume of plasma. Samples from 160 CML patients and 180 control individuals without CML were tested. Cells and plasma samples from 93 of the CML patients were re-analyzed 3-12 months after imatinib treatment. Ratios of BCR-ABL:ABL mRNA in paired cell and plasma samples of the 160 CML patients correlated significantly (r=0.83; p<0.001). When results were compared directly using the sign test, the pre-therapy plasma results were significantly different from those from peripheral blood cells (p=0.028), but not bone marrow cells (p=0.119). Absolute levels of BCR-ABL mRNA in plasma strongly correlated with many laboratory characteristics in pre-therapy CML patients. Higher BCR-ABL: ABL ratios were detected in plasma samples at all time points after treatment, although this was significant only at 3 months (p=0.0003). In cases in which results from the assays disagreed, minimal residual disease was detected in plasma samples significantly more frequently than in cell samples (p<0.001). Plasma was a reliable source for monitoring BCR-ABL mRNA levels. Minimal residual disease detection from plasma was more sensitive than from cell samples. Our results suggest that absolute levels of BCR-ABL mRNA per unit volume of plasma may reflect tumor load.

Expression of cyclooxygenase-2 mRNA in peripheral blood of head and neck cancer patients and in healthy controls. A pilot study

Conclusions. Cyclooxygenase-2 mRNA (COX2) levels are higher in head and neck cancer (HNC) patients than in controls and this correlates with tumor size and outcome. These findings suggest the use of this parameter as a future tumor marker. Objective. We analyzed the expression of COX2 mRNA in peripheral blood cells in HNC patients and in healthy controls and its relationship with outcome and progression-free survival. Materials and methods. Blood samples were obtained from 41 consecutive HNC patients and 16 healthy controls and analyzed for COX2 mRNA with quantitative real-time polymerase chain reaction and compared with β-actin as a house-keeping gene. Results. Treatment consisted of surgery only (4 patients), chemoradiotherapy (18), chemotherapy followed by curative surgery (4) or palliative chemotherapy (15). COX2 mRNA levels were higher in patients with unfavorable outcome (mean 6.8, median 2.06) than those with favorable outcome (mean 1.2, median 1.31) (p=0.062). Both were higher than for healthy controls (mean 0.74, median 0.72; p<0.001). In bulky tumors, the percentage of level over 6 in unfavorable outcome cases was higher than in the favorable outcome cases (p=0.005). In chemotherapy patients with level ≤1 no relapse or progression was observed (n=7), and progression-free survival was significantly better than those with level >1 (n=19) (p=0.0138).

Functional analysis of splicing mutations and of an exon 2 polymorphic variant ofSERPING1/C1NH

Several sequence changes have been reported in hereditary angioedema patients in intron 2 of the SERPING1/C1NH gene, but their consequences on splicing have not been determined. We examined in cell transfection assays the consequences at the mRNA level of splicing mutations affecting either the +3 or the +5 donor site positions, or the conserved canonical splicing signals of exon 2, using mutant C1 inhibitor minigene constructs. Both intron 2 mutations, c.51+3A>G and c.51+5G>A, resulted in marked exon 2 skipping in these assays, but also yielded a large fraction of normal transcripts. We show that the c.51+3A>G mutation cosegregates with low C1 inhibitor protein levels in one family. Moreover, the second base of exon 2 of the SERPING1/C1NH gene is the site of a polymorphic variant, which has been proposed as a modifier of disease severity. We found that the c.-21C allele at this position yields low but significant levels of exon 2 skipping in transfected Hep G2 or Hep 3B cells, suggesting that this allele may contribute, at the RNA level, to more severe forms of angioedema. Furthermore, we describe a previously not detected alternative splicing of exon 3, found in peripheral blood cell mRNA but not in the liver or in hepatoma cell lines and we show that, in cultured monocytes of a patient carrying the c.51+3A>G mutation, this alternative splicing is shifted from exon 3 exclusion to skipping of both exons 2 and 3. The latter finding suggests that mutations affecting splicing of exon 2 of the SERPING1/C1NH gene may have different consequences in monocytes versus other cell types.

Expression of Pregnane-X-Receptor Transcript in Peripheral Blood Mononuclear Cells and Correlation with Mdr1 Mrna

P-glycoprotein (P-gp) limits bioavailability and accumulation of HIV protease inhibitors (PIs). PIs are ligands for the pregnane-X-receptor (PXR), which regulates P-gp expression. This occurs when ligands activate the receptor, initiating binding to response elements in the MDR1 promoter. PXR also activates cytochrome P4503A4 (CYP3A4) and a correlation between hepatic PXR and CYP3A4 mRNA has been reported. We have examined the relationship between MDR1 and PXR mRNA in peripheral blood cells and demonstrate a significant correlation in 18 volunteers (R2=0.4; P<0.005). PXR was approximately 250-fold lower in peripheral blood mononuclear cells than in liver (1.6+/-1.2 vs 450+/-298; n=6; P<0.01).

Expression of granzyme B mRNA is altered in human immunodeficiency virus infected patients

CD8-positive cytotoxic T lymphocytes and natural killer cells are the major cytotoxic components of the antiviral immune response. The major pathway used by these cells in response to viral-infected cells involves granzymes, cytotoxic granule serine proteases involved in the pathway leading to target cell DNA fragmentation and apoptosis. The levels of granzyme B mRNA in peripheral blood cells of human immunodeficiency virus (HIV) type-1 infected patients in comparison to noninfected individuals were assessed by quantitative competitive reverse transcriptase polymerase chain reaction. Expression of granzyme B mRNA is altered in HIV-1 infected patients. Significantly fewer HIV patients had detectable granzyme B mRNA levels than controls. The one HIV-infected patient with detectable granzyme B mRNA displayed a much higher level of this mRNA than all healthy controls. Cell-mediated cytotoxicity during HIV-1 infection may be impaired due to a deficient quantity of active cytotoxic granules or to their abnormal regulation.