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  1. Amrina Mohamad Amin, Maha Abdullah, Sabariah Md Noor, Raudhawati Osman, Wan Hayati Mohd Yaacob, Cheong Soon Keng
    MyJurnal
    Introduction: Acute myeloid leukaemia (AML) is a clonal haematological neoplasm characterised by proliferation of immature myeloid cells in the bone marrow resulting in impairment normal cell development in bone marrow. This leads to anaemia, thrombocytopenia and neutropenia. AML primarily affects older adults, with a median age at diagnosis of 69 years but is also seen in all other age groups. AML is recognized as a kind of cancer with marked heterogeneity in both biology of the cells and reactions to treatment. Treatment with intensive chemotherapy regi-mens of adult AML patients who are ≤ 60 years old results in hematologic remission in about 35% of patients, but at least 30% of these patients will experience a relapse. Mechanism leading to early relapse is still unclear. Leukaemia stem cell (LSC) is shown to correlate with poor prognosis. Biomarkers such as aldehyde dehydrogenase (ALDH) and CD34+CD38- have been identified as potential LSC biomarkers in previous studies. The objective of this study is to examine the expression of such markers for LSC and determine the association. Methods: Peripheral blood or bone marrow samples from untreated, newly diagnosed acute myeloid leukemias of all age, gender and race were collect-ed from Hospital Melaka and Kelang. Diagnosis of AML is based on WHO classification which include morphology, cytochemistry, immunophenotyping and cytogenetics. Mononuclear cells were isolated from bone marrow aspirate samples by gradient density centrifugation on Ficoll-Hypaque. Immunophenotyping using CD13, CD14, CD33, CD34, CD38 and ALDH were carried out to identify the presence and proportion of the various populations of inter-est. Results: There was a strong, positive correlation between ALDH and CD34+CD38- cell population, which was statistically significant (rs = 0.5989, p< 0.05). Conclusion: The strong correlation of ALDH activity and CD34+CD38- expression supported the potential of these biomarkers to identify LSCs cell in AML patients. However, due to the heterogeneity of AML, further studies using more markers and larger sample size are needed to determine the validity and to correlate with disease-free survival rate of AML patients.
  2. Pei-Shin, Chai, Siti Zuleha Idris, Norfarazieda Hassan, Nur Ramziahrazana Jumat, Zainina Seman, Sharmili Vidyadaran, et al.
    MyJurnal
    The immune system responds to stimulus by activation/increase or inhibition/decrease in activities. These immu-nomodulatory effects may be triggered by various factors in the environment including cytokines, hormones and growth factors, as well as flavonoids, antioxidants and various antigens in food and the environment. Immunosup-pression has a direct effect on the capacity of the immune system to fight against infection and cancer formation. A pro-inflammatory response, however, may induce further progression of tumours that had formed. Inflammation is also associated with many chronic illnesses including pain. The suppressive effects from phytochemicals have been shown in the potential to reduce T-lymphocyte proliferation in vitro and in vivo. Studies have demonstrated inhibi-tion of pro-inflammatory cytokines from flavonoid such as naringenin, green tea polyphenol extract, encapsulated fruit and vegetable juice powder concentrate. Feijoa sellowiana Berg var. coolidge fruit juice consumption exerted anti-inflammatory activity on edema-induced mice within first hour of treatment while agipenin, a natural flavonoid reduced neuroinflammation by protection against damage from dendritic cells stimulated T cells in experimental autoimmune encephalomyelitis mouse models. Dietary polyphenols were found to exert a regulatory role on den-dritic cell function. Our own study showed immunosuppressive effect from increased T regulatory cells from papaya consumption. Increased regulatory cells are associated with cancer conditions. On the other hand, grape juice con-sumption mobilized gamma–delta T cells. Ginseng berry extract increased pro-inflammatory molecules in dendritic cells in the spleen while polysaccharide fractions from Momorica charantia, an edible medicinal vegetable increased various immune indexes. Fruits may also have endo-immunomodulatory function causing differential effects in male and female. Sex hormones can influence immune changes based on sex as seen in increased NK cells in males and antibodies in females. We observed a population of CD4-CD45RA-CD69+CD25- cells was significantly lower in males. However, none of these studies have been directly conducted on cancers. Investigation into this area may help improve decision making in cancer management.
  3. Leong CF, Raudhawati O, Cheong SK, Sivagengei K, Noor Hamidah H
    Pathology, 2003 Oct;35(5):422-7.
    PMID: 14555387
    AIMS: Epithelial membrane antigen (EMA) or MUC1 belongs to a heterogeneous group of heavily glycosylated proteins and is expressed in most normal and epithelial neoplastic cells. EMA is also expressed in plasma cells, anaplastic large cell lymphoma (Ki-1 antigen), malignant histiocytosis and erythroleukaemia. In 1996, Cheong et al. (Hematology 1996; 1: 223) demonstrated the positive expression of EMA in monoblasts. Since there were very few useful markers for differentiating subtypes of acute myeloid leukaemia with a monocytic component from the those without, a study was conducted to evaluate the prevalence of EMA expression and its relationship with known markers for monocytic-macrophage lineage (CD11c, CD14 and intracellular CD68) in monocytes and monoblasts.

    METHODS: EMA detection was performed by flow cytometry in monocytes and monoblasts. EMA expression was compared with other known markers of monocytic-macrophage lineage (CD11c, CD14 and intracellular CD68). Samples of purified monocytes were obtained from 20 healthy volunteers. Twenty-two cases of monocytic AML (M4 and M5) were studied and controls were selected from 20 cases of acute lymphoblastic leukaemia (ALL) and 18 cases of non-monocytic AML (M0, M1, M2, M3, and M7).

    RESULTS: EMA was shown to be expressed strongly on the surface of all purified monocytes. EMA expression was observed on blast cells in 18/22 (81.8%) cases of AML M4 and M5, but not in that of non-monocytic AML or ALL. In this study EMA monoclonal antibody has demonstrated a strong association (P<0.001) with all the other known markers of monocytic-macrophage lineage in acute leukaemia subtypes. EMA had also shown 100% specificity and 81.8% sensitivity in the diagnosis of AML M4 and M5.

    CONCLUSIONS: The monoclonal antibody EMA (clone E29) is a useful marker in the classification of acute myeloid leukaemia and can be used as a supplementary analysis for the diagnosis of acute leukemia with monocytic involvement.

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