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Chronic myeloid leukemia (CML) has made a milestone progress due to the development of the first generation tyrosine kinase inhibitor(TKI). Nowadays, most clinical trials in CML focus on discontinuation, even the second discontinuation, and the third generation TKI against T315I mutation. The conventional treatments are more focused on decreasing BCR-ABL transcripts rapidly. At the same time, the treatment management of some special patients has been valued.

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Chronic myeloid leukemia (CML) has made a milestone progress due to the development of the first generation tyrosine kinase inhibitor(TKI). Nowadays, most clinical trials in CML focus on discontinuation, even the second discontinuation, and the third generation TKI against T315I mutation. The conventional treatments are more focused on decreasing BCR-ABL transcripts rapidly. At the same time, the treatment management of some special patients has been valued.

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A great progress has been made in the treatment of chronic myeloid leukemia (CML) owing to the first generation tyrosine kinase inhibitor (TKI). Nowadays, more and more hematologists are eager to understand how to rapidly reduce the BCR-ABL transcripts level, and to get the standard therapeutic reactions, which emerges the second generation TKI. However, the first and second generation TKI have the potential of drug resistance, and thus the third and fourth generation TKI may resolve this problem. Imatinib drug discontinuation trial emphasizes the importance of digital polymerase chain reaction (PCR) and the probability of the second treatment-free remission.

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Chronic lymphocytic leukemia (CLL) is one of the common lymphoid malignancies. Single agent ibrutinib has 74％ progression-free survival (PFS) rate in RESONATE-2 trial, but ibrutinib-based therapy combined with obinutuzumab or rituximab in recent iLLUMINTE trial and ALLIANCE trail have 79％ and 88％ PFS rate respectively, which brings encouraging results. New inhibitors and chimeric antigen receptor T-cell (CAR-T) immunotherapy provide new treatment regimens for CLL patients who relapsed after receiving ibrutinib. The clinical trials have been done in phase Ⅰ/Ⅱ.

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The 59th American Society of Hematology (ASH) Annual Meeting is known as the most powerful hematological meeting around the world. The outcomes in the meeting showed the progress of current hematological diseases from the fundamental research to the clinical practice, from the diagnosis to the treatment. The 59th ASH Annual Meeting covered the contents from the improvement of the formal treatment of acute myelogenous leukemia to the strategies of the aggressive B-cell lymphoma, from the prospect on myelodysplastic syndromes to the influence of biological features on the treatment strategies of indolent lymphoma, from the individualized treatment of chronic lymphocytic leukemia to the study on acquired or hereditary bone marrow failure. The inspiring outcomes from the scholars in China have gained good reputations from the international.

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The diagnosis and treatment of multiple myeloma (MM) have make remarkable progress, which were reviewed in the 57th American Society of Hematology (ASH) annual meeting. In this annual meeting, the effects of advanced proteasome inhibitor (PI), antibody, checkpoint blockade, immunomodulatory agent (IMiD), histone deacetylase (HDACI) and chimeric antigen receptor T-cell (CAR-T), and new diagnostic technologies were reported. The real point is to apply the best available diagnosis and therapy at this meeting. At present, regardless of advances, all of randomized clinical trials push to combined agents, and combined with hematopoietic stem cell transplantation, efficacy will be improved in further. So some professors also refered to 2015 year as 'the advance year of MM'.

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BACKGROUND: Lychas mucronatus is one scorpion species widely distributed in Southeast Asia and southern China. Anything is hardly known about its venom components, despite the fact that it can often cause human accidents. In this work, we performed a venomous gland transcriptome analysis by constructing and screening the venom gland cDNA library of the scorpion Lychas mucronatus from Yunnan province and compared it with the previous results of Hainan-sourced Lychas mucronatus. RESULTS: A total of sixteen known types of venom peptides and proteins are obtained from the venom gland cDNA library of Yunnan-sourced Lychas mucronatus, which greatly increase the number of currently reported scorpion venom peptides. Interestingly, we also identified nineteen atypical types of venom molecules seldom reported in scorpion species. Surprisingly, the comparative transcriptome analysis of Yunnan-sourced Lychas mucronatus and Hainan-sourced Lychas mucronatus indicated that enormous diversity and vastly abundant difference could be found in venom peptides and proteins between populations of the scorpion Lychas mucronatus from different geographical regions. CONCLUSIONS: This work characterizes a large number of venom molecules never identified in scorpion species. This result provides a comparative analysis of venom transcriptomes of the scorpion Lychas mucronatus from different geographical regions, which thoroughly reveals the fact that the venom peptides and proteins of the same scorpion species from different geographical regions are highly diversified and scorpion evolves to adapt a new environment by altering the primary structure and abundance of venom peptides and proteins.

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The potassium channel Kv1.3 is an attractive pharmacological target for T-cell-mediated autoimmune diseases, and specific and selective peptidic blockers of Kv1.3 channels have served as valuable therapeutic leads for treating these diseases. Here, we found a new peptide toxin, J123, with 43 amino acids including six cysteine residues by screening the venomous cDNA library of scorpion Buthus martensii Karsch, which has been used as traditional medicine in China for more than 2000 years. The sequence analysis suggested that peptide J123 constituted a new member of the alpha-KTx toxins. The electrophysiological experiments further indicated that peptide J123 has a novel pharmacological profiles: it blocked Kv1.3 channel with high potency (IC50=0.79 nM), and exhibited good selectivity on Kv1.3 over Kv1.1 (>1000-fold) and Kv1.2 (about 30-fold), respectively. Furthermore, peptide J123 had no activity on SKCa2 and SKCa3 channels at micromolar concentration level. Based on the pharmacological activities, the possible channel-interacting surface of peptide J123 was also predicted by molecular modeling and docking. All these data not only enrich the knowledge of the structure-function relationship of the new Kv1.3-speicific peptide but also present a potential drug candidate for selectively targeting Kv1.3 channels.

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The HIV-1 envelope glycoproteins are assembled by the trimeric gp120s and gp41s proteins. The gp120 binds sequentially to CD4 and coreceptor for initiating virus entry. Because of noncovalent interaction and heavy glycosylation for envelope glycoproteins, it is highly difficult to determine entire envelope glycoproteins structure now. Such question extremely limits our good understanding of HIV-1 membrane fusion mechanism. Here, a novel and reasonable assembly model of trimeric gp120s and gp41s was proposed based on the conformational dynamics of trimeric gp120-gp41 complex and gp41, respectively. As for gp41, the heptad repeat sequences in the gp41 C-terminal is of enormous flexibility. On the contrary, the heptad repeat sequences in the gp41 N-terminal likely present stable three-helical bundle due to strong nonpolar interaction, and they were predicted to associate three alpha1 helixes from the non-neutralizing face of the gp120 inner domain, which is quite similar to gp41 fusion core structure. Such interaction likely leads to the formation of noncovalent gp120-gp41 complex. In the proposed assembly of trimeric gp120-gp41 complex, three gp120s present not only perfectly complementary and symmetrical distribution around the gp41, but also different flexibility degree in the different structural domains. Thus, the new model can well explain numerous experimental phenomena, present plenty of structural information, elucidate effectively HIV-1 membrane fusion mechanism, and direct to further develop vaccine and novel fusion inhibitors.

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Breast cancer is the most common malignancy among women, and mutations in the BRCA1 gene produce increased susceptibility to these malignancies in certain families. In this study, the forward 1-13 exons of breast cancer associated gene BRCA1 were cloned from breast cancer cell line ZR-75-30 by RT-PCR method. Sequence analysis showed that nine BRCA1 splice forms were isolated and characterized, compared with wild-type BRCA1 gene, five splice forms of which were novel. These splice isoforms were produced from the molecular mechanism of 5' and 3' alternative splicing. All these splice forms deleting exon 11b and the locations of alternative splicing were focused on two parts:one was exons 2 and 3, and the other was exons 9 and 10. These splice forms accorded with GT-AG rule. Most these BRCA1 splice variants still kept the original reading frame. Western blot analysis indicated that some BRCA1 splice variants were expressed in ZR-75-30 cell line at the protein level. In addition, we confirmed the presence of these new transcripts of BRCA1 gene in MDA-MB-435S, K562, Hela, HLA, HIC, H9, Jurkat and human fetus samples by RT-PCR analysis. These results suggested that breast cancer associated gene BRCA1 may have unexpectedly a large number of splice variants. We hypothesized that alternative splicing of BRCA1 possibly plays a major role in the tumorigenesis of breast and/or ovarian cancer. Thus, the identification of cancer-specific splice forms will provide a novel source for the discovery of diagnostic or prognostic biomarkers and tumor antigens suitable as targets for therapeutic intervention.

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Previously reported results showed that the BmKK2's intron could be recognized and spliced in cultured HEK 293T cells. At the same time, a cryptic splicing site of BmKK2 gene was found in the second exon. Moreover, replacing BmKK2's intron with BmP03's intron (an artificial BmKK2-BmP03 mosaic gene) did not affect the intron's recognition and splicing, but increased the expression level of the toxin-GFP fusion protein (Cao et al., J Biochem Mol Toxicol 2006;20:1-6). In this investigation, the BmKK2's intron with 79 nucleotides length was artificially shifted from the 49th nt (the 17th Gly codon between the first base and the second base) to the 100th nt (the 34th Gly codon between the first base and the second base). Based on the constructed intron-splicing system, the results of RT-PCR and the western blotting analysis showed that the BmKK2's shifted-intron (named BmKK2-s) was not recognized and spliced correctly, but the cryptic splicing site of BmKK2 gene was still spliced in the second exon, which possibly indicated that locations of introns were very important to the recognition and splicing of introns, and splicing of introns was very much associated with the corresponding upstream and downstream exons. This result possibly provides evidence for splice-site recognition across the exons.

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Using GFP as a reporter gene, splicing of scorpion toxin gene BmKK2 was investigated in cultured HEK 293T cells. The results of RT-PCR and western blotting showed that BmKK2's intron could be recognized and spliced in cultured HEK 293T cells. At the same time, a cryptic splicing site of BmKK2 gene was found at the 91st nucleotide site of the second exon, which is a typical form of alternative splicing. For the first time, alternative splicing would partially explain the diversity of scorpion toxins at the gene level. Moreover, replacing BmKK2's intron with BmP03's intron (an artificial BmKK2-BmP03 mosaic gene) did not affect the intron's recognition and splicing, but increased the expression of the toxin-GFP fusion protein by fluorescence imaging, which indicated that both introns may regulate the expression of toxin-GFP fusion protein. The artificial BmKK2-BmP03 mosaic gene was also spliced into two kinds of mRNA molecules, which showed that sequence of intron was not absolutely conserved. The results suggested that introns of scorpion toxin genes BmKK2 and BmP03 increase the diversity of scorpion toxins and regulate the expression of their genes.

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The diversity of scorpion venom peptides is well shown by the presence of about 400 such polypeptides with or without disulfide bonds. Scorpion toxins with disulfide bonds present a variety of sequence features and pharmacological functions by affecting different ion channels, while the venom peptides without disulfide bonds represent a new subfamily, having much lower sequence homology among each other and different functions (e.g. bradykinin-potentiating, antimicrobial, molecular cell signal initiating and immune modulating). Interestingly, all scorpion venom peptides with divergent functions may have evolved from a common ancestor gene. Over the lengthy evolutionary time, the diversification of scorpion venom peptides evolved through polymorphism, duplication, trans-splicing, or alternative splicing at the gene level. In order to completely clarify the diversity of scorpion toxins and toxin-like peptides, toxinomics (genomics and proteomics of scorpion toxins and toxin-like peptides) are expected to greatly advance in the near future.

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Many studies have been carried on peptides and genes encoding scorpion toxins from the venom of Mesobuthus martensii Karsch (synonym: Buthus martensii Karsch, BmK), such as Na+, K+ and Cl- channel modulators. In this study, a novel calcium channel toxin-like gene BmCa1 was isolated and characterized from the venom of Mesobuthus martensii Karsch. First, a partial cDNA sequence of the Ca2+ channel toxin-like gene was identified by random sequencing method from a venomous gland cDNA library of Mesobuthus martensii Karsch. The full-length sequence of BmCa1 was then obtained by 5'RACE technique. The peptide deduced from BmCa1 precursor nucleotide sequence contains a 27-residue signal peptide and a 37-residue mature peptide. Although BmCa1 and other scorpion toxins are different at the gene and protein primary structure levels, BmCa1 has the same precursor nucleotide organization and cysteine arrangement as that of the first subfamily members of calcium channel scorpion toxins. Genomic DNA sequence of BmCa1 was also cloned by PCR. Sequence analysis showed that BmCa1 gene consists of three exons separated by two introns of 72 bp and 1076 bp in length, respectively. BmCa1 is the first calcium channel toxin-like gene cloned from the venom of Mesobuthus martensii Karsch and potentially represents a novel class of calcium channel toxins in scorpion venoms.

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A full-length cDNA sequence encoding for the precursor of a venom peptide (named BmKCT) with homology to chlorotoxin has been isolated from a cDNA library made from the venom glands of the Chinese Scorpion Buthus martensii Karsch. The sequence of BmKCT is similar (68 % identities) to that of chlorotoxin isolated from Leiurus quinquestriatus quinquestriatus. To understand the biological function of BmKCT, this peptide was expressed using pGEX expression system and purified using GST affinity column and gel filtration.Whole cell patch-clamping recording showed that BmKCT could significantly inhibit chloride currents of gliomas cells, and the inhibitory effect was reversible. These results suggested that BmKCT might belong to the class of short chain toxins blocking the chloride ion channels.

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Scorpion venom contains many small polypeptide toxins, which can modulate Na(+), K(+), Cl(-), and Ca(2+) ion-channel conductance in the cell membrane. A full-length cDNA sequence encoding a novel type of K(+)-channel toxin (named BmTxKS4) was first isolated and identified from a venom gland cDNA library of Buthus martensii Karsch (BmK). The encoded precursor contains 78 amino acid residues including a putative signal peptide of 21 residues, propeptide of 11 residues, and a mature peptide of 43 residues with three disulfide bridges. BmTxKS4 shares the identical organization of disulfide bridges with all the other short-chain K(+)-channel scorpion toxins. By PCR amplification of the genomic region encoding BmTxKS4, it was shown that BmTxKS4 composed of two exons is disrupted by an intron of 87 bp inserted between the first and the second codes of Phe (F) in the encoding signal peptide region, which is completely identical with that of the characterized scorpion K(+)-channel ligands in the size, position, consensus junctions, putative branch point, and A+T content. The GST-BmTxKS4 fusion protein was successfully expressed in BL21 (DE3) and purified with affinity chromatography. About 2.5 mg purified recombinant BmTxKS4 (rBmTxKS4) protein was obtained by treating GST-BmTxKS4 with enterokinase and sephadex chromatography from 1 L bacterial culture. The electrophysiological activity of 1.0 microM rBmTxKS4 was measured and compared by whole cell patch-clamp technique. The results indicated that rBmTxKS4 reversibly inhibited the transient outward K(+) current (I(to)), delayed inward rectifier K(+) current (I(k1)), and prolonged the action potential duration of ventricular myocyte, but it has no effect on the action potential amplitude. Taken together, BmTxKS4 is a novel subfamily member of short-strain K(+)-channel scorpion toxin.

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All scorpion toxins from different 30 species are simply reviewed. A new classification system of scorpion toxins is first proposed: scorpion toxins are classified into three families (long-chain scorpion toxins with 4 disulfide bridges, short-chain scorpion toxins with 3 disulfide bridges, and intermediate-type scorpion toxins with 3 or 4 disulfide bridges). Intermediate-type scorpion toxins provide a strong proof for the conclusion that channel toxins from scorpion venoms evolve from a common ancestor. Common organization of precursor nucleotides and genomic sequence, similar 3-dimensional structure, and the existence of intermediate type scorpion toxins and functionally intercrossing scorpion toxins show that all scorpion toxins affecting ion channels evolve from the common ancestor, which produce millions of scorpion toxins with function-diversity.

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<p><b>OBJECTIVE</b>To investigate the effects of BmkTXK(beta), a newly purified 'long chain' peptide inhibitor of K(+) channels from the Chinese scorpion Buthus martensi Karsch (BmK), on the electrophysiological properties of isolated rabbit atrial myocytes.</p><p><b>METHODS</b>The standard whole-cell patch-clamp technique was used to study the effects of multiple concentrations of BmkTXK(beta) on potassium currents and action potentials.</p><p><b>RESULTS</b>BmkTXK(beta) produced concentration-dependent prolongation of action potential duration at 20%, 50%, and 90% repolarization (APD(20,50,90)) without any use-dependence. Meanwhile, it had no significant effect on RMP, APA, or V(max) (n = 9). At a dose of 1 micro mol/L, BmkTXK(beta) decreased I(to) by 41.4% (n = 10, P < 0.01) at a membrane potential of +50 mV [from (13.63 +/- 0.87) pA/pF to (7.98 +/- 0.78) pA/pF]. I(to) was reduced significantly with an IC(50) value of 1.82 micromol/L (95% confidence interval: 1.47 - 2.17 micro mol/L), in a clear concentration-dependent manner. BmkTXK(beta) blocked I(Ks) and I(Ks),tail with an IC(50) of 20.15 micromol/L and a 95% confidence interval of 16.93 - 23.37 micromol/L. At a concentration of 10 micromol/L, BmkTXK(beta) blocked both I(Ks) (mean reduction 37.3% +/- 4.2%, P < 0.01, n = 7) and I(Ks), tail (mean reduction 35.8% +/- 4.1%, P < 0.01, n = 7). At 0 mV, 10 micromol/L BmkTXK(beta) inhibited both I(Kr) (mean reduction 40.5% +/- 2.6%, P < 0.01, n = 6) and I(Kr), tail (mean reduction 42.3% +/- 2.9%, P < 0.01, n = 6). Blocking of I(Kr) by BmkTXK(beta) occurred in a concentration-dependent manner, with an IC(50) of 17.21 micromol/L (95% confidence interval: 14.76-19.66 micromol/L). An absence of effects on I(K1) was observed for BmkTXK(beta), with no change in reversal-potential (n = 6, P > 0.05).</p><p><b>CONCLUSIONS</b>BmkTXK(beta) exerts direct blocking effects on several potassium channels involved in cardiac repolarization, and has a strong effect on prolonging the repolarization of rabbit cardiomyocytes without reverse frequency dependence. This finding suggests that BmkTXK(beta) could be a promising class III drug for anti-arrhythmic therapy without the risk of proarrhythmia.</p>

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