Analysis of Genomic Landscape in Patients with Acute Myeloid Leukemia / 中国实验血液学杂志

OBJECTIVE@#To investigate the gene mutation occurved in AML patients with 29 kinds of fusion genes and 51 kinds of tumor gene.@*METHODS@#Next-generation sequencing (NGS) was used to detected the 49 kinds of targeted gene. FLT3 internal tandem duplication (FLT3-ITD), CALR, NPM1 and CEBPA mutation were detected by DNA-based PCR and Sanger sequencing. Twenty-nine kinds of fusion genes were dected by multiplex nested RT-PCR.@*RESULTS@#The total gene mutation rate was 91% (109/121) in all the 121 patients. On average, 2.1 mutated genes per patient were identified, among these 121 patients, coexistence of ≥ 3 mutations was frequent (34.7%). The most commonly mutated genes were NRAS (23.96%, n=29), followed by NPM1 (14.04%, n=17), CEBPA double mutations (14.04%, n=17), KRAS (11.57%, n=14)，FLT3-ITD (10.74%, n=13), CSF3R (10.74%, n=13), TET2 (9.92%, n=12) and IDH1 (9.1%, n=11). Overall, fusion genes were detected in 47 (37.3%) patients, including AML/ETO (n=12), CBFβ/MYH11 (n=11), PML/RARa (n=12), MLL rearranagement realated mutation MLL-X (n=10). TLS/ERG (n=1) and DEK/CAN (n=1) in an order of decreasing frequency. Patients with normal karyotype (NK)- AML exhibited more mutations in CEBPA, NPM1, TET2, RUNX1 and IDH1, comparing with abnormal karyotype patients. KRAS mutation in abnormal kayotype patients was significantly higher than that in normal kayotype patients (P=0.014). TP53 mutations were predominantly associated with complex cytogenetics (P=0.199). KRAS mutations were more frequent in core binding factor (CBF) acute myeloid leukemia (AML) and 11q23/MLL rearrangement leukemia, compared with NK-AML (P=0.006 and 0.003, respectively). KIT mutations predominated in CBF-AML (P=0.006). JAK2V617F mutations were detected in two patients and co-occurred with AML-ETO fusions.@*CONCLUSION@#At least one mutation is observed in more than 90% patients. On average, more than 2 mutated genes per patient are identified. Some gene mutations are associated with gene rearrangement.

Recent advances in pMHC multimer technology / 中国免疫学杂志

To overcome the intrinsic low affinity between peptide bound major histocompatibility complex(pMHC) and T cell receptors (TCRs) on T cell surface,pMHC can be multimerized to enhance its avidity to TCRs.Since 20 years ago pMHC tetramer was first applied in the detection of antigen specific T cells,it has become one of the most important immunoassay tools.Recently,pMHC multimers have been significantly improved over the original tetramer.pMHC multimers with higher valence have been produced in order to enhance detection sensitivity.Additionally,reversible pMHC multimers,which can be released from T cell surface to avoid potential damage to T cells,also have been applied in the isolation of antigen specific T cells.As a class of molecular tools,pMHC multimers play an important role in immunoassays and immunotherapies.A good knowledge and effective utilization of those tools will be greatly helpful in scientific and clinical applications.

Gene expression of collagen types IX and X in the lumbar disc / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To study gene expression of collagen types IX and X in human lumbar intervertebral discs during aging and degeneration and to explore the role of collagen types IX and X in disc degeneration.</p><p><b>METHODS</b>Fetal, adult and pathologic specimens were subjected to in situ hybridization with cDNA probes to investigate mRNA-expressions of types IX and X collagen gene.</p><p><b>RESULTS</b>In fetal intervertebral discs, positive mRNA hybridization signals of type IX collagen were concentrated in the nucleus pulposus and the inner layer of anulus fibrosus. Interstitial matrix of the nucleus pulposus also showed positive type X collagen staining. Positive mRNA hybridization signals of types IX and X were not detected in the middle and outer layers of anulus fibrosus. In adult specimens, expression of type IX collagen mRNA was markedly decreased. No hybridization signals of type X collagen was observed. As for pathological specimens, there was no gene expression of type IX collagen. In severe degenerated discs from adults, there were focal positive expressions of type X collagen.</p><p><b>CONCLUSIONS</b>Obvious changes of collagen gene expression occur with aging. Expression of type IX collagen decreases in adult and pathological discs. Results of type X collagen expression suggest that type X collagen is expressed only in older adult and senile discs (i.e., when disc degeneration has already reached a terminal stage), indicating the terminal stage of degeneration.</p>