Wang Fx

Expression and mutation analysis of genes that encode the Myc antagonists Mad1, Mxi1 and Rox in acute leukaemia

The Myc antagonists Mad1, Mxi1 and Rox proteins share two highly conserved domains, Sin3-interacting domain (SID) and basic helix-loop-helix leucine zipper domain (bHLHzip), which are essential for these proteins to function during molecular switching from proliferation to differentiation. In an attempt to identify mutations in Mad1, Mxi1 and Rox genes in human haematological malignancies, we screened 10 haematopoietic cell lines, bone marrow mononuclear cells (BMMNC) from 26 patients with haematological malignancies and peripheral blood mononuclear cells (PBMNC) from 30 healthy volunteers, using reverse transcription-polymerase chain reaction, single strand conformation polymorphism analysis and sequencing. Mad1, Mxi1 and Rox genes were expressed in all samples. Four polymorphisms were found in cell lines BMMNC and PBMNC: two in Mad1, one in Mxi1 and one in Rox. Nine missense mutations were detected: two in Mad1 in patients, four in Mxi1 (three in patients and one in KG-1 cell line), and three in Rox in patients. No mutations were detected in PBMNC from healthy volunteers. Among six patients with acute lymphoblastic leukaemia, two had Mxi1 mutations and another two had Rox mutations. These mutations were associated with poorer clinical outcomes. This is the first report to show that Mad1, Mxi1 and Rox genes were expressed and displayed mutations in haematological malignancies.

T cell acute lymphoblastic lymphoma complicated with myeloid sarcoma in an adult: A case report

The present case report describes a rare case of T cell acute lymphoblastic lymphoma (T-LBL) in the lymph node with myeloid sarcoma in the pericardium. A 33-year-old Chinese male was admitted to hospital on 4 July 2015 exhibiting a fever and having experienced wheezing and fatigue for the previous 7 days. Routine pathological, computed tomographic, cytological and immunophenotypic observations revealed a diagnosis of T-LBL in the lymph node on 7 August 2015, without evidence of bone marrow (BM) involvement. The patient received induction chemotherapy for T-LBL and achieved partial remission. The patient was identified to have multiple serous effusion and analysis of pericardial effusion cells revealed the diagnosis of T-LBL with extramedullary myeloid sarcoma (without BM involvement) on 25 November 2015. On 30 December 2015, the patient was identified to exhibit proliferation of primary myeloid cells in the peripheral blood and BM, and an abnormal karyotype in BM cells, indicating that the complicated myeloid sarcoma involved the BM. No matched donor was available so the patient received chemotherapy to manage the disease. The patient was discharged on 31 January 2016 and ceased treatment. The patient succumbed on 19 February 2016 at home. To the best of our knowledge, T-LBL complicated with myeloid sarcoma had not been previously reported in Chinese adult male patients. In addition, the involvement of the BM and aberrant karyotype of the complicated myeloid sarcoma in the patient were rare.

THE CLINICAL SIGNIFICANCE OF MULTIDRUG RESISTANCE GENE (mdrl) EXPRESSION IN ACUTE LEUKEMIA

Objective: To study the clinical significance of multidrug resistance gene expression in acute leukemia. Methods: The relationships between drug resistance of leukemia cells and prognosis, multidrug resistance gene (mdr1) were examined in 85 patients with acute leukemia and 20 normal controls by reverse transcriptase poly-merase chain reaction (RT-PCR). Results: The mdrl positive rate in untreated group was 44.7%. The complete remission (CR) rate of mdr1 positive patients (23.9%) was significantly lower than that of mdr1 negative patients (88.5%) (P<0.005). The mdr1 expression level in relapsed-refractory group was higher than that of CR group. A gradually increased mdr1 mRNA level in CR patients indicated early relapse. Conclusion: The mdr1 positive rate in normal control and long-term survival patients was very low. The mdr1 expression was correlated with French-American-British Cooperative Group (FAB) classification. The mdr1 expression level was correlated with chemotherapeutic effect and prognosis. It is an unfavorable prognostic factor for patients with acute leukemia.