Quantitative Detection of Circulating Nucleophosmin Mutations DNA in the Plasma of Patients with Acute Myeloid Leukemia

Objective: The aim of this study was to quantify the copies of circulating nucleophosmin (NPM) mutations DNA in the plasma of patients with acute myeloid leukemia (AML) and to explore the association of circulating NPM mutation levels with clinical characteristics.Design and Methods: The presence of NPM mutations in 100 Chinese patients newly diagnosed with AML were identified by RT-PCR and sequencing analysis. Copies of circulating NPM mutation A (NPM mut.A) DNA in the plasma of mutation-positive cases were quantified by real-time quantitative PCR (qRT-PCR). Furthermore, the association of circulating NPM mutation levels and clinical characteristics was analyzed.Results: NPM mutations were identified in 37 of the 100 patients and all cases were NPM mut.A. The circulating NPM mut.A levels ranged from 0.35×10⁸ copies/ml to 6.0×10⁸ copies/ml in the 37 mutation-positive cases. The medium and quartile M (P25, P75) of the circulating NPM mut.A levels in patients classified as M2, M4 and M5 morphological subtypes were 1.35×10⁸ (0.76×10⁸, 1.91×10⁸) copies/ml, 1.81×10⁸ (1.47×10⁸, 2.2×10⁸) copies/ml and 2.50×10⁸ (2.42×10⁸, 3.05×10⁸) copies/ml, respectively. Circulating NPM mut.A levels were significantly higher in patients with the M5 subtype of AML compared to patients with the M2 and M4 subtypes (p=0.000, p=0.046). In addition, circulating NPM mut.A copies were significantly associated with a higher white blood cell count, platelet count and bone marrow blast percentage (p<0.05).Conclusion: Our results suggest that circulating NPM mutations DNA assay serves as a complementary to the routine investigative protocol of NPM-mutated leukemia.     

Detection of the nucleophosmin gene mutations in acute myelogenous leukemia through RT-PCR and polyacrylamide gel electrophoresis

Objectives: Mutations in the C‐terminal region of the nucleophosmin (NPM1) gene occur in approximately 60% of acute myeloid leukemia (AML) cases with normal karyotype and represent the most common genetic lesion presently known in this disease. Because of their frequency and favorable impact on prognostic outcome, screening for this aberration is currently recommended in routine diagnostic characterization of AML. Several techniques enabling to detect NPM1 mutation have been reported, but all require sophisticated equipment, which represent an obstacle particularly in countries with limited resources. Methods: We designed an RT‐PCR strategy to amplify NPM1 exon 12 followed by electrophoresis and fragment visualization on polyacrylamide gels to discriminate a 4–5 bp size difference resulting from mutations in this gene. A hemi‐nested method was designed to increase sensitivity for the study of minimal residual disease (MRD). Results: The assay enabled specific detection of NPM1 mutations in 12/36 patients. A 10^?2 sensitivity level was obtained using one amplification round, while the hemi‐nested PCR approach yielded a 10^?5 sensitivity level, therefore proving useful to assess MRD in patients carrying the mutation. The results were independently validated in 24 AML cases by sequencing analysis. Conclusions: This simple and low‐cost assay may integrate diagnostic work‐up of AML and could be used for assessment of response to therapy in patients with NPM1 mutations.     

Granulocyte colony‐stimulating factor improves neuron survival in experimental spinal cord injury by regulating nucleophosmin‐1 expression

Granulocyte colony‐stimulating factor (G‐CSF) and its related mechanisms were investigated to assess the potential for this factor to exert neuroprotective effects against spinal cord injury in mice. Recombinant human granulocyte colony‐stimulating factor (rhG‐CSF) was injected into mice spinal cord hemisection models. Locomotor activity was assessed by using the Basso‐Bettie‐Bresnahan scale. Neurons isolated from spinal cords were cultured in vitro and used in a neuronal mechanical injury model. Three treatment groups were compared with this model, 1) G‐CSF, 2) G‐CSF + NSC348884 (a nucleophosmin 1‐specific inhibitor), and 3) NSC348884. Immunofluorescence staining and Western blotting were performed to analyze the expression of G‐CSF and nucleophosmin 1 (Npm1). TUNEL staining was performed to analyze apoptosis after G‐CSF treatment. We found that the G‐CSF receptor (G‐CSFR) and Npm1 were expressed in neurons and that Npm1 expression was induced after G‐CSF treatment. G‐CSF inhibited neuronal apoptosis. NSC348884 induced p53‐dependent cell apoptosis and partially blocked the neuroprotective activity of G‐CSF on neurons in vitro. G‐CSF promoted locomotor recovery and demonstrated neuroprotective effects in an acute spinal cord injury model. The mechanism of G‐CSF's neuroprotection may be related in part to attenuating neuronal apoptosis by NPM1. © 2014 Wiley Periodicals, Inc.     

A comprehensive review on Brigatinib – A wonder drug for targeted cancer therapy in non-small cell lung cancer

The mortality rate in patients suffering from non-small cell lung cancer (NSCLC) is quite high. This type of cancer mainly occurs due to rearrangements in the anaplastic lymphoma kinase (ALK) gene which leads to form an oncogene of fused gene NPM-ALK. Brigatinib is recently approved by FDA in April 2017 as a potent tyrosine kinase inhibitor (TKI) for the NSCLC therapy. In the present scenario, it is no less than a wonder drug because it is indicated for the treatment of advanced stages of metastatic ALK positive NSCLC, a fatal disease to overcome the resistance of various other ALK inhibitors such as crizotinib, ceritinib and alectinib. In addition to ALK, it is also active against multiple types of kinases such as ROS1, Insulin like growth factor-1Receptor and EGFR. It can be synthesized by using N-[2-methoxy-4-[4-(dimethylamino) piperidin-1-yl] aniline] guanidine and 2,4,5-trichloropyrimidine respectively in two different ways. Its structure consists of mainly dimethylphosphine oxide group which is responsible for its pharmacological activity. It is active against various cell lines such as HCC78, H2228, H23, H358, H838, U937, HepG2 and Karpas- 299. Results of ALTA (ALK in Lung Cancer Trial of AP26113) phase ½ trial shows that 90?mg of brigatinib for 7?days and then 180?mg for next days is effective in the treatment of NSCLC. Brigatinib has been shown to have favorable risk benefit profile and is a safer drug than the available cytotoxic chemotherapeutic agents. In comparison to other FDA approved drugs for the same condition, it causes fewer minor adverse reactions which can be easily managed either by changing the dose or by providing good supportive care. This article is intended to provide readers with an overview of chemistry, pharmacokinetic, pharmacodynamic and safety profile of brigatinib, which addresses an unmet medical need.     

The role of nucleophosmin/B23 in radiation-induced chromosomal instability in human lymphoblastoid cells of different p53 genotypes

Purpose:?To investigate the role of nucleophosmin (NPM/B23) in radiation-induced chromosomal instability and apoptosis in human lymphoblastoid cells with different protein 53 (p53) status.

Materials and methods:?Wild type (wt) p53 TK6 and mutant type (mt) p53 WTK1 with or without short hairpin RNA (shRNA)-mediated silencing of NPM, TK6 with or without short interfering RNA (siRNA)-mediated silencing of p53 (p53i and NEGi) were irradiated with 4 Gy gamma-rays. Six to 48?h after irradiation, the index of apoptosis, chromosome aberration, cell cycle distribution and the levels of total NPM and phosphorylated-threonine 199 (pThr¹⁹⁹) NPM proteins were measured. Cells in some dishes were treated with 10?μM Olomoucine (OLO) for 3?h before irradiation and remained in the medium after irradiation.

Results:?The rates of radiation-induced apoptosis in TK6 and TK6/NEGi were about 2-fold of those in WTK1 and TK6/p53i, while the frequencies of polyploidy in TK6 and TK6/NEGi were obviously lower than those in WTK1 and TK6/p53i. Moreover, after irradiation, pThr¹⁹⁹ NPM levels increased significantly in WTK1 and TK6/p53i, and slightly increased in TK6 and TK6/NEGi, indicating that the increased level of pThr¹⁹⁹ NPM was related to p53 status. When Thr¹⁹⁹ hyperphosphorylation of NPM was inhibited by OLO or when NPM was knocked down, we found that radiation-induced apoptosis was more pronounced and polyploidy formation was reduced as compared with negative control while the magnitude of these changes in TK6 was obviously higher than that in WTK1, indicating that NPM has an antagonistic interaction with wt p53.

Conclusions:?NPM/B23 plays an important role in protecting cells from radiation-induced apoptosis and increasing polyploidy formation via either a p53 or non-p53 pathway.     

Role of genotype-based approach in the clinical management of adult acute myeloid leukemia with normal cytogenetics

Acute myeloid leukemia (AML) is the most common form of acute leukemia affecting adults. Although it is a complex disease driven by numerous genetic and epigenetic abnormalities, nearly 50% of patients exhibit a normal karyotype (CN-AML) with an intermediate cytogenetic risk. However, a widespread genomic analysis has recently shown the recurrence of genomic aberrations in this category (mutations of FLT3, CEBPA, NPM1, RUNX1, TET2, IDH1/2, DNMT3A, ASXL1, MLL and WT1) thus revealing its marked genomic heterogeneity. In this perspective, a global gene expression analysis of AML patients provides an independent prognostic marker to categorize each patient into clinic-pathologic subgroups based on its molecular genetic defects. Consistently such classification, taking into account the uniqueness of each AML patient, furnishes an individualized treatment approach leading a step closer to personalized medicine. Overall the genome-wide analysis of AML patients, by providing novel insights into biology of this tumor, furnishes accurate prognostic markers as well as useful tools for selecting the most appropriate treatment option. Moreover it provides novel therapeutic targets useful to enhance efficacy of the current anti-AML therapeutics. Here we describe the prognostic relevance of such new genetic data and discuss how this approach can be used to improve survival and treatment of AML patients.     

Involvement of nucleophosmin/B23 in the response of HeLa cells to UV irradiation.

The steady-state mRNA level of nucleophosmin/B23 in HeLa cells increased after UV irradiation. Nucleophosmin/B23 antisense transfection potentiated ultraviolet (UV)-induced cell killing. A block in G(2)/M phase, larger peak of apoptotic cells and higher caspase-3 in vitro activity were noted in nucleophosmin/B23 antisense-transfected cells compared with vector-transfected cells after UV treatment. Irradiated cells that received vector plasmid exhibited increased levels of [(3)H]thymidine incorporation due to DNA repair synthesis. In contrast, irradiated cells that received nucleophosmin/B23 antisense plasmid exhibited no such increase of [(3)H]thymidine incorporation, indicating inhibition of DNA repair. Cotransfection of cells with vector allowed repair of the damaged chloramphenicol acetyl transferase (CAT) reporter and rescue of CAT activity by host repair machinery. CAT activity in cells cotransfected with nucleophosmin/B23 antisense was less (<50%) than that of vector-transfected cells, indicating reduction of host nucleotide excision repair activity. Lower protein expressions of nucleophosmin/B23 and proliferating cell nuclear antigen (PCNA) were observed in nucleophosmin/B23 antisense-transfected cells compared with vector-transfected cells with or without UV treatment. Cotransfection of nucleophosmin/B23 antisense-transfected HeLa cells with PCNA construct made the cells less susceptible to UV-induced cell killing. Our results indicate that nucleophosmin/B23 correlates with PCNA and DNA repair capacity in cellular sensitivity to UV.     

Cuplike nuclei (prominent nuclear invaginations) in acute myeloid leukemia are highly associated with FLT3 internal tandem duplication and NPM1 mutation

BACKGROUND:

A small subset of patients with acute myeloid leukemia (AML) have cuplike nuclei. Other investigators have demonstrated that these neoplasms have distinctive clinicopathologic and molecular features.

METHODS:

The authors searched for patients who had AML with cuplike nuclei at their institution over a 10‐year interval. A strict definition for cuplike nuclei was used: ≥10% blasts with nuclear invaginations in ≥25% of the nuclear area. The relevant data were reviewed, and the results were compared with a control group of patients who had AML without cuplike nuclei.

RESULTS:

In total, 22 patients who had AML with cuplike nuclei were identified and were classified as AML without maturation (French‐American‐British classification M1) (AML M1). Compared with the control group (AML M1), patients who had AML with cuplike nuclei were associated significantly with fms‐like tyrosine kinase 3 (FLT3)‐internal tandem duplication (ITD) (86% vs 38%, respectively; P = .002); nucleophosmin 1 (NPM1) mutations (86% vs 19%; P < .0001); both mutations (77% vs 14%; P < .0001); normal karyotype (86% vs 40%; P = .003); bone marrow blast count (90% vs 84%; P = .016); myeloperoxidase positivity (95% vs 30% blasts; P = .001); higher D‐dimer levels (>5000 ng/mL vs 569 ng/mL; P = .001); and the absence of CD7 (91% vs 52%; P = .007), CD34 (82% vs 5%; P < .0001), and human leukocyte antigen, D‐related (59% vs 10%; P = .001). There were no differences in age, sex, or peripheral blood counts. The positive predictive value of recognizing AML with cuplike nuclei for FLT3‐ITD, NPM1, and both mutations was 81%, 86%, and 77%, respectively.

CONCLUSIONS:

Cuplike nuclei in AML were highly associated with the presence of NPM1 and FLT3‐ITD mutations and with several clinicopathologic and immunophenotypic features. Recognition of the distinctive morphologic features of AML with cuplike nuclei may be helpful in streamlining the workup of these neoplasms. Cancer 2009. © 2009 American Cancer Society.     

Optimizing CIGB-300 intralesional delivery in locally advanced cervical cancer

Background:

We conducted a phase 1 trial in patients with locally advanced cervical cancer by injecting 0.5 ml of the CK2-antagonist CIGB-300 in two different sites on tumours to assess tumour uptake, safety, pharmacodynamic activity and identify the recommended dose.

Methods:

Fourteen patients were treated with intralesional injections containing 35 or 70 mg of CIGB-300 in three alternate cycles of three consecutive days each before standard chemoradiotherapy. Tumour uptake was determined using ⁹⁹Tc-radiolabelled peptide. In situ B23/nucleophosmin was determined by immunohistochemistry.

Results:

Maximum tumour uptake for CIGB-300 70-mg dose was significantly higher than the one observed for 35 mg: 16.1±8.9 vs 31.3±12.9 mg (P=0.01). Both, AUC_24h and biological half-life were also significantly higher using 70 mg of CIGB-300 (P<0.001). Unincorporated CIGB-300 diffused rapidly to blood and was mainly distributed towards kidneys, and marginally in liver, lungs, heart and spleen. There was no DLT and moderate allergic-like reactions were the most common systemic side effect with strong correlation between unincorporated CIGB-300 and histamine levels in blood. CIGB-300, 70 mg, downregulated B23/nucleophosmin (P=0.03) in tumour specimens.

Conclusion:

Intralesional injections of 70 mg CIGB-300 in two sites (0.5 ml per injection) and this treatment plan are recommended to be evaluated in phase 2 studies.