Secondary Abnormalities Research Articles

Secondary Myelodysplasia-Associated Metaphase Cytogenetic Abnormalities in Newly Diagnosed Multiple Myeloma Treated On Total Therapies 2 & 3– Influence of Cumulative Dosing of Maintenance Drugs

AbstractAbstract 324▪▪This icon denotes a clinically relevant abstract Background:There has been recent evidence that lenalidomide, while used in the treatment of myelodysplastic syndromes (MDS), also has been associated with an enhanced risk of secondary malignancies including MDS. Here we are examining the impact of maintenance on the development of metaphase-based MDS-associated cytogenetic abnormalities (MDS-CA), and subsequent development of therapy related MDS (t-MDS) and acute leukemia (t-AL) in the two arms of Total Therapy 2 (TT2) and two successive Total Therapy 3 trials (TT3A, TT3B). Methods:The details of TT2/TT3A/TT3B trials and patient outcomes have been reported previously. TT2 (median follow-up 118 months) patients were then randomized to receive thalidomide maintenance (TT2+Thal) for 3 years versus no thalidomide (TT2-Thal). Maintenance in TT3A (median follow-up 78 moths) consisted of VTD in the first year and TD for years 2 and 3 in TT3A, while TT3B (median follow-up 48 months) employed VRD for all 3 years. The patient populations were as follows: TT2-Thal arm (n=283), TT2+Thal arm (n=270), TT3A (n=279) and TT3B (n=162). Bone marrow examination with conventional cytogenetics was performed at baseline, post-induction, post-transplant and then at least semi-annually from maintenance in all patients prospectively. Chi-square and Fisher's exact tests were used to compare baseline characteristics between protocols. Univariate and multivariate Cox proportional hazard regression were used to model associations between baseline covariates and onset of MDS-CA and t-MDS/t-AL. Kaplan and Meier method was used to model cumulative incidence of MDS-CA and t-MDS/t-AL. Results:Baseline characteristics were fairly comparable between the two arms of TT2 and the two TT3 studies, except a higher proportion of GEP70 high risk patients in TT3B. Cumulative incidence of MDS-CA was significantly higher in TT3B protocol from time of first transplant (Figure 1), with the most common cytogenetic abnormality being deletion of chromosome 20 (del20, 35%), followed by monosomy/deletion 7 (27%) and monosomy/deletion 5 (17%) across all protocols. Of the 71 patients with an MDS-CA, 29 were also diagnosed with clinical MDS or AML; for these 29 patients, the median time to this diagnosis from first transplant was 58 months. The cumulative incidence of MDS-CA was higher and achieved more statistical significance (Figure 2) in TT3B compared to TT3A when landmarked from the start of maintenance. In univariate analysis for all patients, TT3B emerged as a significant variable in the univariate Cox regression model for MDS-CA, and in both the univariate and multivariate models for del20. Univariate and multivariate modeling within TT3B patient population did not reveal significance with cumulative dosing of different maintenance drugs. Discussion:Three randomized phase III trials (IFM-2005-02, CALGB 101104 and MM-015) have demonstrated an increase incidence of second malignancies in patients receiving lenalidomide maintenance after having been exposed to alkylating agent melphalan. In our present study, we are reporting an increased incidence of MDS-CA in the TT3B trial that employed VRD maintenance when compared with predecessor TT3A and TT2 trials. The data suggests that the risk is associated with lenalidomide exposure rather than its cumulative dosing in patients with prior exposure to therapy with alkylating agents. [Display omitted] Pairwise log-rank comparisons:TT3B vs. TT3A:p-value = 0.0206TT3B vs. TT2-Thal:p-value = 0.0134TT3B vs. TT2+Thal:p-value = 0.0178TT3A vs. TT2-Thal:p-value = 0.1502TT3A vs. TT2+Thal:p-value = 0.3134TT2-Thal vs. TT2+Thal:p-value = 0.8863 [Display omitted] Disclosures:Sawyer:University of Arkansas for Medical Sciences: Employment, under panding process, under panding process Patents & Royalties.

Mutant laboratory mice with abnormalities in hair follicle morphogenesis, cycling, and/or structure: An update

Human hair disorders comprise a number of different types of alopecia, atrichia, hypotrichosis, distinct hair shaft disorders as well as hirsutism and hypertrichosis. Their causes vary from genodermatoses (e.g. hypotrichoses) via immunological disorders (e.g. alopecia areata, autoimmune cicatrical alopecias) to hormone-dependent abnormalities (e.g. androgenetic alopecia). A large number of spontaneous mouse mutants and genetically engineered mice develop abnormalities in hair follicle morphogenesis, cycling, and/or hair shaft formation, whose analysis has proven invaluable to define the molecular regulation of hair growth, ranging from hair follicle development, and cycling to hair shaft formation and stem cell biology. Also, the accumulating reports on hair phenotypes of mouse strains provide important pointers to better understand the molecular mechanisms underlying human hair growth disorders. Since numerous new mouse mutants with a hair phenotype have been reported since the publication of our earlier review on this matter a decade ago, we present here an updated, tabulated mini-review. The updated annotated tables list a wide selection of mouse mutants with hair growth abnormalities, classified into four categories: Mutations that affect hair follicle (1) morphogenesis, (2) cycling, (3) structure, and (4) mutations that induce extrafollicular events (for example immune system defects) resulting in secondary hair growth abnormalities. This synthesis is intended to provide a useful source of reference when studying the molecular controls of hair follicle growth and differentiation, and whenever the hair phenotypes of a newly generated mouse mutant need to be compared with existing ones.

Guidelines for the investigation and management of mantle cell lymphoma.

The guideline group was selected to be representative of UK-based medical experts and patients representatives. Ovid MEDLINE, EMBASE and NCBI Pubmed were searched systematically for publications in English from 1980 to 2011 using the MeSH subheading 'lymphoma, mantle cell' and 'lymphoma, mantle cell' as a keyword, as well as all subheadings. In addition, all references to mantle cell lymphoma in the World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissue (Swerdlow et al, 2008) and the British Committee for Standards in Haematology (BCSH) Guideline: Best Practice in Lymphoma Diagnosis and Reporting (Parker et al, 2010) have been included. The writing group produced the draft guideline, which was subsequently revised by consensus by members of the Haemato-oncology Task Force of the BCSH. The guideline was then reviewed by a sounding board of approximately 50 UK haematologists, the BCSH and the British Society for Haematology Committee and comments incorporated where appropriate. The 'GRADE' system was used to quote levels and grades of evidence, details of which can be found in Appendix I. The objective of this guideline is to provide healthcare professionals with clear guidance on the investigation and management of patients with mantle cell lymphoma. The guidance may not be appropriate to patients with other lymphoma sub-types and in all cases individual patient circumstances may dictate an alternative approach.

Lymphoscintigraphy in plastic bronchitis, A pediatric case report

Plastic bronchitis (PB) is an uncommon, potentially fatal disease, marked by endobronchial cast formation causing variable degrees of respiratory distress. Primary and secondary pulmonary lymphatic abnormalities have been identified among the underlying mechanisms of cast formation. We present a case of PB where lymphoscintigraphy demonstrated the underlying lymphatic defect. A 6-year-old Hispanic male with congenital heart disease (CHD; post-Fontan) presented with recurrent pneumonia, respiratory distress. Bronchoscopy showed inflamed hypervascular mucosa and thick mucus plugs; no casts were seen. Later, PB was diagnosed after the patient expectorated a bronchial cast. Cast analysis showed lymphocytic aggregates with mucin and fibrin. Lymphoscintigraphy revealed abnormal lymphatic collaterals and retrograde trace reflux into the superior mediastinum, a picture consistent with thoracic duct lymph leakage into the tracheobronchial tree. The pathogenesis of PB is not fully understood, especially in patients with CHD. Chyle in bronchial casts suggests abnormal lymphatic flow. Reports of lymph flow abnormalities, especially endobronchial lymph leakage in CHD are limited. Lymphoscintigraphy in our case demonstrated clear evidence of retrograde lymph reflux and leakage into the bronchial tree. The case presented suggests that in some patients following Fontan surgery, high intrathoracic lymphatic pressure and retrograde lymph flow may contribute to recurrent cast formation. Finding the underlying lymphatic abnormality helps in specific case management. Lymphoscintigraphy is a safer and easier method than lymphangiography. Surgical lymphatic-venous shunting may be possible in select cases.

CSF N-Glycan Profiles to Investigate Biomarkers in Brain Developmental Disorders: Application to Leukodystrophies Related to eIF2B Mutations

BackgroundPrimary or secondary abnormalities of glycosylation have been reported in various brain diseases. Decreased asialotransferrin to sialotransferrin ratio in cerebrospinal fluid (CSF) is a diagnostic marker of leukodystrophies related to mutations of genes encoding translation initiation factor, EIF2B. We investigated the CSF glycome of eIF2B-mutated patients and age-matched normal individuals in order to further characterize the glycosylation defect for possible use as a biomarker.Methodology/Principal FindingsWe conducted a differential N-glycan analysis using MALDI-TOF/MS of permethylated N-glycans in CSF and plasma of controls and eIF2B-mutated patients. We found in control CSF that tri-antennary/bisecting and high mannose structures were highly represented in samples obtained between 1 to 5 years of age, whereas fucosylated, sialylated structures were predominant at later age. In CSF, but not in plasma, of eIF2B-mutated patient samples, we found increased relative intensity of bi-antennary structures and decreased tri-antennary/bisecting structures in N-glycan profiles. Four of these structures appeared to be biomarker candidates of glycomic profiles of eIF2B-related disorders.ConclusionOur results suggest a dynamic development of normal CSF N-glycan profiles from high mannose type structures to complex sialylated structures that could be correlated with postnatal brain maturation. CSF N-glycome analysis shows relevant quantitative changes associated with eIF2B related disorders. This approach could be applied to other neurological disorders involving developmental gliogenesis/synaptogenesis abnormalities.

A first description of chronic arthritis and uveitis in an adolescent girl with glycogen storage disease

Purpose Glycogen storage disease (GSD) type 1a is an autosomal recessive inborn error of carbohydrate metabolism which affects glycogenolysis and gluconeogenesis. Severe fasting hypoglycemia and secondary biochemical abnormalities such as hyperuricemia occur. Molecular analysis differentiates GSD type 1 into different clinical phenotypes, of which Type 1b but not Type 1a, is associated with inflammatory bowel disease (IBD). While gout has been described in GSD, chronic arthritis and uveitis have not.

Neurotransmitter abnormalities and response to supplementation in SPG11

Objective: To report the detection of secondary neurotransmitter abnormalities in a group of SPG11 patients and describe treatment with l-dopa/carbidopa and sapropterin.Design: Case reports.Setting: National Institutes of Health in the Undiagnosed Disease Program; Children's National Medical Center in the Myelin Disorders Bioregistry Program.Patients: Four SPG11 patients with a clinical picture of progressive spastic paraparesis complicated by extrapyramidal symptoms and maculopathy.Interventions: l-Dopa/carbidopa and sapropterin.Results: 3/4 patients presented secondary neurotransmitter abnormalities; 4/4 partially responded to l-dopa as well as sapropterin.Conclusions: In the SPG11 patient with extrapyramidal symptoms, a trial of l-dopa/carbidopa and sapropterin and/or evaluation of cerebrospinal fluid neurotransmitters should be considered.

Morphology and Morphometry of Cauda Epididymal Spermatozoa in Rattus rattus L.

Sperm morphometry, in combination with other morphological traits and sperm parameters, can be useful for developing a fertility index. In present study various morphological and morphometric characters of cauda epididymal spermatozoa from 30 house rats were measured. About 100 spermatozoa of each rat with normal morphology and abnormalities like abnormal head, midpiece swelling, coiled tail, bent tail, detached heads and cytoplasmic droplets were counted in different fields and percentage of each was calculated. About 50 spermatozoa of each rat were measured for head length (HL), mid piece length (MPL), tail length (TL), head area (HA) and head perimeter (HP) using Magnus pro analytic software. In cauda epididymal spermatozoa of rat primary abnormalities included abnormal heads and mid piece swelling and secondary abnormalities included cytoplasmic droplet, coiled tails, bent tails, free heads. Variation among the sperm abnormalities was considerably high (>50 %). There was little variation in HL, MPL, TL, HA and HP of cauda epididymal spermatozoa of 30 rats (<13 %).

“Onion” flap

Nail fold deformities from burn injury frequently result in eponychial retraction, proximal nail exposure, pain, and distal phalangeal function impairment. Secondary nail abnormalities including longitudinal ridges, surface cracks, and fragility are common sequelae to nail fold deformities. Surgical management of postburn nail fold deformity is challenging because of scar contractures involving the dorsum of digits and lack of surrounding healthy tissues that can be used as source of soft tissue for reconstruction. Previous reports have discussed several methods for reconstruction of these deformities. However, all of these methods are associated with significant donor site morbidities. From August 2008 to January 2010, "onion" flap reconstruction was performed for postburn nail fold contractures and deformities on 32 fingers of eight patients (five men and three women; average age, 44.4 years; age range, 23-54 years). This novel technique was used to release scar contractures in the eponychial area and allow soft tissue restoration by redraping the eponychium in a single-step procedure. All 32 fingers received single-stage "onion" flap reconstruction for their nail fold deformities at least 6 months after the initial injury. The follow-up period, with an average of 7.8 months, revealed that all nails had good esthetic and functional results. All experienced amelioration of nail abnormalities. The "onion" advancement flap had effectively released the scar contracture around the nail fold and simultaneously restored the eponychial fold. The "onion" flap technique provides superior results compared with those from conventional techniques. We recommend it as the mainstay of treatment for reconstruction of the postburn eponychial deformities. V, therapeutic study.

Occurrence of acute lymphoblastic leukemia and juvenile myelomonocytic leukemia in a patient with Noonan syndrome carrying the germline PTPN11 mutation p.E139D

Noonan syndrome (NS) is a common autosomal dominant condition characterized by short stature, congenital heart defects, and dysmorphic facial features caused in approximately 50% of cases by missense mutations in the PTPN11 gene. NS patients are predisposed to malignancies including myeloproliferative disorders or leukemias. We report a female NS patient carrying a PTPN11 germline mutation c.417 G > C (p.E139D), who developed in her second year of life an acute lymphoblastic leukemia (ALL) and after remission, she developed at 4 years of age a juvenile myelomonocytic leukemia (JMML). Molecular genetic analysis of lymphoblastic blasts at the time of the ALL diagnosis revealed the germline mutation in a heterozygous state, while in the myelomonocytic blasts occurring with JMML diagnosis, the mutation p.E139D was found in a homozygous state due to a uniparental disomy (UPD). These findings lead to the suggestion that the pathogenesis of ALL and JMML in our patient is due to different mechanisms including somatically acquired secondary chromosomal abnormalities.

Germ-line GATA2 p.THR354MET mutation in familial myelodysplastic syndrome with acquired monosomy 7 and ASXL1 mutation demonstrating rapid onset and poor survival

While most myelodysplastic syndrome/acute myeloid leukemia cases are sporadic, rare familial cases occur and provide some insight into leukemogenesis. The most clearly defined familial cases result from inherited mutations in RUNX1 or CEBPA. Recently, novel germline mutations in GATA2 have been reported. We, therefore, investigated individuals from families with one or more first-degree relatives with myelodysplastic syndrome/acute myeloid leukemia with wild-type RUNX1 and CEBPA, for GATA2 mutations. Screening for other recurrent mutations was also performed. A GATA2 p.Thr354Met mutation was observed in a pedigree in which 2 first-degree cousins developed high-risk myelodys-plastic syndrome with monosomy 7. They were also observed to have acquired identical somatic ASXL1 mutations and both died despite stem cell transplantation. These findings confirm that germline GATA2 mutations predispose to familial myelodysplastic syndrome/acute myeloid leukemia, and that monosomy 7 and ASXL1 mutations may be recurrent secondary genetic abnormalities triggering overt malignancy in these families.

A novel dic (17;18) (p13.1;q11.2) with loss of TP53 and BCR/ABL rearrangement in an Imatinib resistant chronic myeloid leukemia

BackgroundThe so-called Philadelphia (Ph) chromosome is present in more than 90% of chronic myeloid leukemia (CML) cases. It results in juxtaposition of the 5′ part of the BCR gene on chromosome 22 to the 3′ part of the ABL gene on chromosome 9. Since the majority of CML cases are currently treated with Imatinib, variant rearrangements in general have no specific prognostic significance, although the mechanisms involved in resistance to therapy have yet to be investigated. The T315I mutation within the abl-gene is the most frequent one associated with resistance to tyrosine kinase inhibitors.ResultsThis study evaluated a Ph chromosome positive CML case resistant to imatinib mesylate. A dic(17;18), loss of TP53 gene, co-expression of b2a2 and b3a2 fusions transcript and a T315I mutation were found.ConclusionsWe reported here a novel case of a Ph chromosome positive CML with a secondary abnormality [dic(17;18)], resulting to Glivec resistance but good response to nilotinib. The dic(17;18) might be a marker for poor prognosis in CML. Our finding indicated for an aggressive progression of the disease. The patient died under the treatment due to unknown reasons.

Low-Dose Glucocorticoid Therapy Complements the Pituitary-Adrenocortical System and Reduces Anxiety and Insomnia in Myasthenia Gravis Patients

Myasthenia gravis (MG) is an autoimmune disorder generally mediated by antibodies against the acetylcholine receptors of the skeletal muscles. Depending on the disease burden, MG patients may experience chronic dysregulation of both the hormonal stress axis and the immune system, consequently, aggravating the disease itself but also leading to secondary psychopathological abnormalities. A long-term clinical course requires long-term glucocorticoid (GC) therapy, which may change the psychological state by affecting the pituitary-adrenocortical system in MG patients. In this study, we investigated the function of the pituitary-adrenocortical system in MG patients who were treated with prednisolone (PSL) and evaluated their quality of life by using the Medical Outcomes Study 36-item Short-Form Health Survey and the 28-item general health questionnaire (GHQ-28). ACTH and cortisol levels in the plasma of patients who were treated with PSL (PSL[+] group, n = 18) were lower than those in the plasma of patients who were treated without PSL (PSL[-] group, n = 29; P < 0.05 and P < 0.01, respectively). In the PSL(+) group, we confirmed that cortisol levels negatively correlated with daily PSL dosages (P < 0.05). The anxiety and depression scores from the GHQ-28 in the PSL(+) group were lower than those in the PSL(-) group (P < 0.05, respectively). There was no significant correlation between cortisol levels and corticotropin levels in plasma of the PSL(-) group. However, we confirmed that corticotropin levels positively correlated with cortisol levels in plasma (P < 0.01) and negatively correlated with anxiety/insomnia scores from the GHQ-28 (P < 0.05) in the PSL(+) group. In conclusion, low-dose GC treatment complemented the pituitary-adrenocortical system and improved the psychological state in MG patients.

A new dic(7;12)(p12.21;p12.2) and i(12)(q10) during the lymphoid blast crisis of patient with Ph+ chronic myeloid leukemia

Chronic myelogenous leukemia (CML) is a common myeloproliferative disease that is characterized by the clonal expansion of marrow stem cells, and is associated with the Philadelphia chromosome. As the disease progresses, additional chromosome abnormalities may arise. The prognostic impact of secondary chromosomal abnormalities in CML is complex, heterogeneous, and sometimes related to previous treatment. Here, we describe a CML patient in lymphoid blast crisis associated with a new chromosomal abnormality identified, dic(7;12)(p12.21;p12.2) and i(12)(q10) using classical cytogenetics and spectral karyotype analysis. To the best of our knowledge, this is the first report of t(7;12)(p11.1;q11.1) and i(12)(q10) in a CML patient with lymphoid evolution.

Effect of sperm concentration in an ejaculate on morphometric traits of spermatozoa in Duroc boars

The experimental material consisted of 75 ejaculates collected form 8 Duroc boars. The ejaculates were divided into three groups according to sperm concentration in an ejaculate. An ejaculate was obtained from each boar monthly and it was used to make microscopic preparations to examine spermatozoa morphology. In each preparation morphometric measurements were taken of fifteen randomly selected spermatozoa characterized by normal morphology. The following measurements of spermatozoa were taken: length and width of the spermatozoa head, head area, length of the flagellum, perimeter of the spermatozoon head and total spermatozoon length. The results were used to calculate indicators of spermatozoa morphology. Moreover, assessments were made of frequency of morphological defects to isolate spermatozoa with primary and secondary abnormalities following the Blom classification system. It was found that the concentration of spermatozoa in the ejaculate influenced the morphometric characteristics of spermatozoa. Ejaculates with low sperm concentrations are characterized by larger spermatozoa as compared to ejaculates with high sperm concentrations. However, sperm concentration in the ejaculate does not much influence the shape of spermatozoa.

The Nup98-HoxA9 Leukemogenic Fusion Protein Blocks Xpo1 and Tap-Mediated Nuclear Export

Abstract 5228In leukemia Nup98 fusion genes are found as a product of the reciprocal translocation between Nucleoporin 98 (nup98) and homeobox-cluster genes. Nup98-HoxA9 (NHA9), the product of the t(7;11) translocation, is detected in acute myeloid leukemias (AMLs) and as a secondary abnormality in blast crisis of chronic myeloid leukemia (CML). The role of NHA9 in leukemogenesis is complex and incompletely understood. Here, we show an abrogation of nucleocytoplasmic shuttling of the nuclear export receptor Xpo1 and Tap in NHA9-expressing cells by using retroviral nuclear trafficking as a model. Lentiviral Rev, the prototype for nuclear export signal (NES)-containing proteins is shuttled through the nucleopore by Xpo1. NHA9 sequestered Xpo1 from the nuclear rim into nuclear aggregates resulting in deficient Xpo1-dependent nuclear exit of Rev and its mRNA substrates. Tap is involved in mRNA nucleocytoplasmic shuttling and is also responsible for the nuclear export of D-type retrovirus CTE-mRNAs. By using Tap/CTE-mRNA nuclear export as a model we also found that Tap colocalized in NHA9 nuclear aggregates leading to impaired Tap-mediated nuclear exit of CTE-mRNA substrates. Leukemogenicity of Nup98 fusion proteins may be accounted for in part by defects in Tap and Xpo1-mediated export of their substrates. Disclosures:No relevant conflicts of interest to declare.

MiR-125b Cooperates with BCR-ABL and Enhances Therapy Resistance in Childhood Ph+ ALL

Abstract 78The treatment improvements in the past two decades led childhood acute lymphoblastic leukemia (ALL) cure rates reach over 80%, but children who carry the Philadelphia (Ph+) chromosome still have high risk of relapse due to therapy resistance. Different results with large series of patients have shown that an earlier remission after induction with glucocorticoids and intrathecal methotrexate is correlated to a better outcome. Besides, the minimal residual disease (MRD) risk measured after induction is also correlated to the therapy response, indicating that an early response can predict Ph+ ALL overall outcome. Several studies have shown that Ph+ ALL is heterogeneous in terms of clinical parameters even if all patients carry BCR-ABL and most of them carry the oncogenic isoform of IKAROS. They respond differently to the treatment, which suggests the presence of additional mechanisms involved in leukemogenesis. In an attempt to find secondary genetic abnormalities that may be responsible for the Ph+ ALL chemo resistance and heterogeneity, we studied the miRNA expression profile in two patient groups discriminated by the initial therapy response.We included samples from 78 consecutive Ph+ ALL children diagnosed in Italy between 2000 and 2010. The miRNA signature was analyzed by miRNA array using Applied Biosystems Array-Cards comparing two patient groups differentiated according to MRD and prednisone response. A particular miRNA profile was found in the poor responder group and it was confirmed using specific miRNA single assays from AB. Specially the miR-125b was up to ten-fold overexpressed compared to the good responder group (p =.006). To investigate the functional role of miR-125b in Ph+ ALL we used BCR-ABL positive cell lines (3 ALL and one CML in blast-crisis) to create a xenograft leukemia model and induced miRNA upregulation by direct inoculation of synthetic miR-125b (premiR). Tumors injected with premiR-125b (n=14) were significantly bigger than the scrambled oligonucleotide (n=10) and mock controls (n=4) (p=.04). After two weeks the premiR-125b tumors grew six-fold more than controls and average tumor weights for the scrambled oligonucleotides and the premiR-125b inoculated mice were 0.63 g and 1.56 g, respectively (p =.01). Further, we determined whether miR-125b protects the tumor cells from apoptosis after treatment with Dexamethasone. While tumors injected with scrambled molecules were 70% reduced after 10 days of corticoid treatment, tumors injected with premiR-125b were only 30% reduced (p=.05).Together, these results suggest that miR-125b acts as an oncogene in Ph+ ALL and its overexpression accelerates the role of BCR-ABL, increasing therapy resistance and leukemia aggressiveness. Additional studies will be necessary to understand why this miRNA is overexpressed in some patients and how it acts in cooperation with BCR-ABL to induce leukemia. In the future, novel therapies using miRNAs as targets can emerge as strategies to be added to the anti-tyrosine kinase drugs in order to improve treatment response and survivor in Ph+ ALL. Disclosures:No relevant conflicts of interest to declare.

Cytogenetic, Molecular and Clinical Features Associated with Rare CBFB-MYH11 Fusion Transcripts in Patients (Pts) with Acute Myeloid Leukemia (AML) and inv(16)/t(16;16)

Abstract 2514Approximately 8% of de novo AML pts have inv(16)(p13q22) or t(16;16)(p13;q22) [inv(16)] and this cytogenetic group is associated with high complete remission (CR) rates and a relatively favorable outcome after cytarabine/daunorubicin (ara-c/dnr)-based induction and high-dose ara-c (HiDAC) consolidation therapy. However, ∼40% of these pts still relapse. The molecular mechanisms that impact on the prognosis of inv(16) pts remain to be fully elucidated. We and others reported that presence of the mutated KIT (mutKIT) gene is associated with worse outcome, but other contributing factors may play a role. Molecularly, inv(16) results in disruption of the MYH11 gene at 16p13 and CBFB gene at 16q22, creating a CBFB-MYH11 fusion gene. Since the genomic breakpoints within CBFB and MYH11 are variable and the fusion transcripts depend on the exons fused, at least 11 different sized CBFB-MYH11 fusion transcript variants have been found. The frequency of each fusion varies, with ∼85% being type A and ∼5% each types D and E; types B, C, and F-K were reported in single cases (hereafter we refer to non-type A fusions as “rare”). To our knowledge, only one study (Schnittger et al. Leukemia 2007;21:725) has examined the biological and clinical significance of rare CBFB-MYH11 fusions in AML. Fusion type was not found to be prognostic, but the cohort included pts with therapy-related and secondary AML. Thus, further studies are warranted. Accordingly, we analyzed 149 de novo CBFB-MYH11 positive AML pts aged <60 years (y; median, 40 y; range 18–59) receiving ara-c/dnr-based induction and HiDAC consolidation therapy (Cancer and Leukemia Group B protocols 9621, 19808, 10503). Among 149 pts, 129 (87%) had type A fusion, 17 (11%) type E, 2 (1%) type D, and 1 (<1%) type I. Pts with rare fusions had lower white blood cell counts (P=.02; median, 18.9 v 27.5 ×109/L), less often skin infiltration (P=.04; 0% v 18%) and tended to have FAB subtype M4Eo less often than the type A fusion pts (P=.13; 67% v 85%). Eighteen rare and 100 type A fusion pts had at least 1.7 y follow-up and thus could be analyzed for outcome. No significant differences in CR rates (P=1.00; 94% v 92%), cumulative incidence of relapse (CIR; P=.16; 5 y rates, 30% v 47%) or overall survival (OS; P=.30; 5 y rates, 78% v 60%) were found between rare and type A fusion pts. However, a trend toward longer event-free survival (EFS) was observed for rare fusion pts compared with type A pts (P=.07; 5 y rates, 66% v 42%; Figure). In an analysis of secondary cytogenetic abnormalities (abns) we found trisomies 8, 13 and 21 were more frequent in rare fusion pts than in type A pts (P=.03; P=.07; P<.001, respectively). Of the rare fusion pts, 44% had at least one of +8, +13 or +21 compared to only 11% of the type A pts. No rare fusion transcript pt harbored +22, which was present in 24 (19%) pts with type A fusion (P=.05; Table]. Strikingly, no rare fusion pt had mutKIT compared with 29% of type A fusion pts (P=.01). Given that +22 has been associated with improved and mutKIT with worse outcome, we also assessed the impact of fusion transcript type by restricting our analysis first to pts with no +22, then to pts without mutKIT, and finally excluding both +22 and mutKIT. No significant differences in CR rates, CIR, OS or EFS were observed between the two groups. We conclude that the type of fusion transcript does not appear to affect significantly the prognosis of inv(16) pts, although a favorable trend for pts with the rare transcript exists. Type A and rare fusion pts differ with regard to distribution of accompanying genetic or cytogenetic alterations, such as KIT mutation or +22, which did not occur in any of the rare fusion pts. Further studies are required to elucidate if the rare fusion transcripts themselves created the necessary biologic conditions that exclude the concurrent presence of the genome aberrations.TableSecondary abns in pts with rare v type A fusionsAbn type*Rare fusion (n=20†) No. pts (%)Type A fusion (n=129) No. pts (%)P‡None [sole inv(16)]8 (44)81 (63).20+220 (0)24 (19).05+85 (28)11 (9).03+215 (28)2 (2)<.001+132 (11)2 (2).07At least one +8 or +13 or +218 (44)14 (11).001del(7q)/add(7q)0 (0)7 (5).60Other2 (11)11 (9).66*Pts may have multiple secondary abns.†2 unknown.‡Fisher's exact test. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Genetic Response to Lenalidomide in the Circulating Progenitor Cell Compartment of MDS Cohort. Preliminary Results of the Multicenter German LE-MON-5 Study

Abstract 1721 Introduction:LE-MON-5 is a multicenter German phase-II study to verify the safety of monotherapy with lenalidomide (LEN) in MDS patients (pts) with IPSS low or Int-1 and isolated del(5q). We report our cytogenetic results after a monitoring period of sixteen months since start of the trial. Methods:For sequential and frequent survey of LEN-treated pts we applied FISH on enriched CD34+ stem cells from peripheral blood (CD34+ pb) every 2–3 months using a panel of 8 to 13 probes. Karyotyping and FISH on bone marrow aspirates was performed at initial screening and every six months. The median number of analyzed metaphases was 25 (4–30) and FISH analyzing was based on 200 interphase nuclei. Results:We have already screened 94 pts and could confirm isolated del(5q) in 76 (81%). Due to our cytogenetic results demonstrating additional changes in 18/94 (19%) pts, these were registered as screening failures and thus excluded from the study. Until now cytogenetic follow-up data for 40 pts is available. After a median follow-up of 9 months (2–16 months) we have observed a significant impact of LEN on the reduction of the clone size (p < 0.05) by FISH-monitoring. Based on cytogenetic remission, we have separated the cohort into three groups: Fast responders (14/40 (35%) pts) showed a very rapid cytogenetic response to therapy with >50% reduction of 5q- clone size within two months. In the second group, the slow responders, we observed >50% reduction of clone size in 9/40 (22.5%) after > two months. However, two pts showed an increase of 5q- clone after 12 and 13 months respectively after initial response in the sense of a relapse. In the third group, the non responders, (11/34 (27.5%)) we could not observe any cytogenetic response during the as yet limited observation period. In six cases (15%) we detected a reduction of the 5q- clone during follow-up, but the emergence of additional aberrations were also observed such as: 1. trisomy 8 in 6.7% of metaphases after 8 months and is reduced to 3.6% after 12 months, 2. trisomy 4 in 6.7% of metaphases after 6 months and is disappeared after 12 months, followed by emergence of trisomy 8 in 8% of interphase cells, 3. finally, two cases showed loss of Y-chromosome after 4 months in 6% and 19% of CD34+ pb cells, respectively. In CD34+ pb cells of another case, trisomy 8 was detectable after two months in 3.5% of cells. All these new secondary abnormalities occurred in cells with normal chromosomes 5 and were slightly above or below our laboratory thresholds (3 times standard variation). In only one case, a new abnormality emerged in the 5q- clone: In this case additional del(20q) occurred after 2 months in 46% of CD34+ pb cells. In this case no reduction of 5q- cells after 4 months of treatment was observed. However, FISH analysis after 6 months of treatment showed a 14% reduction for both aberrations. To date we could not identify any pts who acquired complex anomalies while treated with LEN. Conclusion:FISH analysis of CD34+ pb cells allows a reliable frequent and relevant genetic monitoring of treatment response to LEN. Our results confirm the positive and rapid effects of LEN on clones with del(5q): Thus, already after 2 months, we could observe up to 90% reduction in the 5q- clone size in 35% of pts. In general, remission rates increased with duration of therapy. We suspect that trisomy 4, 8 and Y-loss are fluctuant “mini clones” without any clinical relevance. Inclusion of additional pts and prolonged observation period will help us to better evaluate the clinical response to LEN. Disclosures:Off Label Use: lenalidomide for MDS del(5q) provided by Celgene for this clinical study. Germing:Celgene: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding. Braulke:Celgene: Honoraria, Research Funding. Schanz:Celgene: Honoraria, Research Funding. Giagounidis:Celgene: Honoraria. Götze:Celgene: Honoraria. Haase:Celgene: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding.

T(3;7)(q26;q21) as a secondary abnormality in MDS RAEB-2

t(3;7)(q26;q21) as a secondary abnormality in MDS RAEB-2