EFFECTS OF CALM /AF10 ANTISENSES ON PRIMARY LEUKEMIC CELLS WITH CALM /AF10 FUSION TRANSCRIPTS IN VITRO

Objectives: To define the involvement of CALM and AF10 fusion transcripts in primary leukaemias with t(10; 11). Methods: The AF10 and CALM fusion in five t(10; 11) leukemia samples were checked by reverse transcriptase-polymerase chain reaction (RT-PCR), and effects of CALM/AF10 antisense phosphorothioate oligodeoxynucleotides (AS PS-ODNs) on chemotherapy sensitivity and apoptosis of leukemia cells in vitro were observed. Results: Five different-sized AF10-CALM products and four different-sized CALM/AF10 products were detected by RT-PCR. The chemotherapy sensitivity of leukemic cells with t(10; 11) to drugs in vitro was lower than that of leukemic cells without t(10; 11). AS PS-ODNs increased the chemotherapy sensitivity and apoptotic rate. There were 4 cases positive at 5 μmol/L concentration, all cases positive at 10 μmol/L and 20 μmol/L concentration, P<0.01 vs only chemotherapeutic drugs (3 cases positive), and chemotherapeutic drugs + S-PS-ODNs (10 μmol/L) (3 cases positive). After cells were treated with 10 μmol/L AS-PS-ODNs + chemotherapeutic drugs for 48 h, 72 h, 96 h, the apoptotic indexes were 14.22±2.86, 29.39±3.57, and 41.26±4.52, respectively. These were significantly higher than those of only chemotherapeutic drugs-treated cells and chemotherapeutic drugs + S-PS-ODNs-treated cells at corresponding time (P<0.01). There was no difference between only drugs group and S-PS-ODNs group at corresponding time (P>0.05). Conclusion: The CALM and AF10 fusion transcripts are involved in the pathogenesis of haematological malignancies with t(10, 11), and is associated with a poor prognosis. AS-PS-ODNs might be useful in therapy of t(10, 11) leukemia. Key words AF10 - CALM - Fusion transcript - Primary leukemia cell - In vitro sensitivity - Antisense oligodeoxynucleotide CLC number R733.7 Biography: LIU Ge-xiu (1968–), male, associate professor, Institute of Hematology, Medical College, Jinan University, majors in hematology.

HBV Integration Induces Complex Interactions between Host and Viral Genomic Functions at the Insertion Site

Hepatitis B virus(HBV),one of the well-known DNA oncogenic viruses,is the leading cause of hepatocellular carcinoma(HCC).In infected hepatocytes,HBV DNA can be integrated into the host genome through an insertional mutagenesis process inducing tumorigenesis.Dissection of the genomic features surrounding integration sites will deepen our understanding of mechanisms underlying integration.Moreover,the quantity and biological activity of integration sites may reflect the DNA damage within affected cells or the potential survival benefits they may confer.The wellknown human genomic features include repeat elements,particular regions(such as telomeres),and frequently interrupted genes(e.g.,telomerase reverse transcriptase[i.e.TERT],lysine methyltransferase 2B[i.e.KMT2B],cyclin E1[CCNE1],and cyclin A2[CCNA2]).Consequently,distinct genomic features within diverse integrations differentiate their biological functions.Meanwhile,accumulating evidence has shown that viral proteins produced by integrants may cause cell damage even after the suppression of HBV replication.The integration-derived gene products can also serve as tumor markers,promoting the development of novel therapeutic strategies for HCC.Viral integrants can be single copy or multiple copies of different fragments with complicated rearrangement,which warrants elucidation of the whole viral integrant arrangement in future studies.All of these considerations underlie an urgent need to develop novel methodology and technology for sequence characterization and function evaluation of integration events in chronic hepatitis B-associated disease progression by monitoring both host genomic features and viral integrants.This endeavor may also serve as a promising solution for evaluating the risk of tumorigenesis and as a companion diagnostic for designing therapeutic strategies targeting integration-related disease complications.