Displaying publications 261 - 280 of 373 in total

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  1. Maha A, Gan GG, Koh CL
    Hematology, 2010 Dec;15(6):382-90.
    PMID: 21114900 DOI: 10.1179/102453310X12719010991902
    T cells undergo a series of complex phenotypic changes before achieving maturation. Discrete stages of T-cell differentiation are simplified to four stages (pro-, pre-, cortical and mature-T cell) and used in the classification of T-cell leukaemia. HLA-DR has been reported to be expressed in immature T-cell acute lymphoblastic leukemia (ALL) and also confer a poorer treatment outcome. Simultaneously, the genotype goes through distinct pattern changes due to rearrangement of T-cell receptor (TCR) genes. TCR gene rearrangement is important in the diagnosis of clonality and used as markers to detect minimal residual disease in lymphoproliferative disorders. We identified a subset within Pro-T and Pre-T cell cases distinguished by the expression of HLA-DR. These subgroups appeared to be more immature as rearrangement of the TCR-gamma gene was either at germline or involved only the first constant region (C1) unlike a more rearranged pattern in the HLA-DR-subgroups. We also observed a higher incidence of mediastinal mass (67%) in the HLA-DR-subgroup in the Pre-T stage. These characteristics may be useful as markers to further refine staging of T-cell ALL and determine prognosis.
    Matched MeSH terms: Leukemia-Lymphoma, Adult T-Cell/classification; Leukemia-Lymphoma, Adult T-Cell/genetics; Leukemia-Lymphoma, Adult T-Cell/pathology*
  2. Peh SC, Kim LH, Thanaletchimy N, Chai SP, Poppema S
    Malays J Pathol, 2000 Jun;22(1):13-20.
    PMID: 16329532
    Lymphoma is a relatively common group of neoplasms diagnosed in hospital practice. This study aims to elucidate the pattern of this disease encountered in a public service hospital of the Ministry of Health, Malaysia.
    Matched MeSH terms: Lymphoma, Non-Hodgkin/ethnology; Lymphoma, Non-Hodgkin/pathology*; Lymphoma, Non-Hodgkin/virology
  3. Batool T, Makky EA, Jalal M, Yusoff MM
    Appl Biochem Biotechnol, 2016 Mar;178(5):900-23.
    PMID: 26547852 DOI: 10.1007/s12010-015-1917-3
    L-asparaginase (LA) catalyzes the degradation of asparagine, an essential amino acid for leukemic cells, into ammonia and aspartate. Owing to its ability to inhibit protein biosynthesis in lymphoblasts, LA is used to treat acute lymphoblastic leukemia (ALL). Different isozymes of this enzyme have been isolated from a wide range of organisms, including plants and terrestrial and marine microorganisms. Pieces of information about the three-dimensional structure of L-asparaginase from Escherichia coli and Erwinia sp. have identified residues that are essential for catalytic activity. This review catalogues the major sources of L-asparaginase, the methods of its production through the solid state (SSF) and submerged (SmF) fermentation, purification, and characterization as well as its biological roles. In the same breath, this article explores both the past and present applications of this important enzyme and discusses its future prospects.
    Matched MeSH terms: Precursor Cell Lymphoblastic Leukemia-Lymphoma
  4. Kim SJ, Yoon DH, Jaccard A, Chng WJ, Lim ST, Hong H, et al.
    Lancet Oncol, 2016 Mar;17(3):389-400.
    PMID: 26873565 DOI: 10.1016/S1470-2045(15)00533-1
    BACKGROUND: The clinical outcome of extranodal natural killer T-cell lymphoma (ENKTL) has improved substantially as a result of new treatment strategies with non-anthracycline-based chemotherapies and upfront use of concurrent chemoradiotherapy or radiotherapy. A new prognostic model based on the outcomes obtained with these contemporary treatments was warranted.

    METHODS: We did a retrospective study of patients with newly diagnosed ENKTL without any previous treatment history for the disease who were given non-anthracycline-based chemotherapies with or without upfront concurrent chemoradiotherapy or radiotherapy with curative intent. A prognostic model to predict overall survival and progression-free survival on the basis of pretreatment clinical and laboratory characteristics was developed by filling a multivariable model on the basis of the dataset with complete data for the selected risk factors for an unbiased prediction model. The final model was applied to the patients who had complete data for the selected risk factors. We did a validation analysis of the prognostic model in an independent cohort.

    FINDINGS: We did multivariate analyses of 527 patients who were included from 38 hospitals in 11 countries in the training cohort. Analyses showed that age greater than 60 years, stage III or IV disease, distant lymph-node involvement, and non-nasal type disease were significantly associated with overall survival and progression-free survival. We used these data as the basis for the prognostic index of natural killer lymphoma (PINK), in which patients are stratified into low-risk (no risk factors), intermediate-risk (one risk factor), or high-risk (two or more risk factors) groups, which were associated with 3-year overall survival of 81% (95% CI 75-86), 62% (55-70), and 25% (20-34), respectively. In the 328 patients with data for Epstein-Barr virus DNA, a detectable viral DNA titre was an independent prognostic factor for overall survival. When these data were added to PINK as the basis for another prognostic index (PINK-E)-which had similar low-risk (zero or one risk factor), intermediate-risk (two risk factors), and high-risk (three or more risk factors) categories-significant associations with overall survival were noted (81% [95% CI 75-87%], 55% (44-66), and 28% (18-40%), respectively). These results were validated and confirmed in an independent cohort, although the PINK-E model was only significantly associated with the high-risk group compared with the low-risk group.

    INTERPRETATION: PINK and PINK-E are new prognostic models that can be used to develop risk-adapted treatment approaches for patients with ENKTL being treated in the contemporary era of non-anthracycline-based therapy.

    FUNDING: Samsung Biomedical Research Institute.

    Matched MeSH terms: Lymphoma, Extranodal NK-T-Cell/diagnosis; Lymphoma, Extranodal NK-T-Cell/mortality*; Lymphoma, Extranodal NK-T-Cell/therapy*
  5. Koh KS, Telisinghe PU, Bickle I, Abdullah MS, Chong CF, Chong VH
    Asian Pac J Cancer Prev, 2015;16(8):3279-83.
    PMID: 25921132
    BACKGROUND: Colorectal cancer (CRC) is the most common gastrointestinal cancer and the incidence is increasing. CRC is more common with increasing age, but a proportion occurs in young adults, termed young CRC. This study assessed the incidence and the demographic of young CRC in Brunei Darussalam.

    MATERIALS AND METHODS: All histologically proven CRC between 1986 and 2014 registered with the Department of Pathology cancer registry were reviewed and data extracted for analyses. Young CRC was defined as cancer in patients aged less than 45 years. The various population groups were categorized into locals (Malays, Chinese and Indigenous) and expatriates.

    RESULTS: Over the study period, there were 1,126 histologically proven CRC (mean age 59.1 ± 14.7 years, Male 58.0%, Locals 91.8% and 8.2% expatriates). Young CRC accounted for 15.1% with the proportion declining over the years, from 29% (1986-1990) to 13.2% (2011-2014). The proportion of young CRC was highest among the indigenous (30.8%), followed by the expatriates (29.3%), Malays (14.3%) and lowest among the Chinese (10.8%). The mean age of young CRC was 35.9 ± 6.2; lowest among the indigenous (33.5 ± 6.7), expatriate (34.9 ± 6.0) groupd and the Malays (35.6 ± 6.5) compared to the Chinese (38.6 ± 4.6), a similar trend being observed in the non-young CRC groups. There were no difference between the genders and tumor locations (rectum or colon) between the young and the non-young CRC cases. Female young CRC was significantly younger than male (p<0.05) without any significant variation between the various population groups (p>0.05).

    CONCLUSIONS: Our study showed that the young CRC accounted for 15.1% of all CRC with declining trend observed over recent years. Young CRC was more common among indigenous, expatriates and Malays and least common among the Chinese. There were no differences in the gender and tumor locations.
    Matched MeSH terms: Lymphoma/ethnology; Lymphoma/epidemiology*; Lymphoma/pathology
  6. Kuan JW, Su AT, Wong SP, Sim XY, Toh SG, Ong TC, et al.
    Transfus Apher Sci, 2015 Oct;53(2):196-204.
    PMID: 25910537 DOI: 10.1016/j.transci.2015.03.017
    There are few randomized trials comparing filgrastim and pegfilgrastim in peripheral blood stem cell mobilization (PBSCM). None of the trials studied the effects of the timing of pegfilgrastim administration on the outcomes of mobilization. We conducted a randomized triple blind control trial comparing the outcomes of filgrastim 5 µg/kg daily from day 3 onwards, 'early' pegfilgrastim 6 mg on day 3 and 'delayed' pegfilgrastim 6 mg on day 7 in cyclophosphamide PBSCM in patients with no previous history of mobilization. Peripheral blood (PB) CD34+ cell count was checked on day 8 and day 11 onward. Apheresis was started when PB CD34+ ≥ 10/µl from day 11 onward. The primary outcome was the successful mobilization rate, defined as cumulative collection of ≥2 × 10(6)/kg CD34+ cells in three or less apheresis. The secondary outcomes were the day of neutrophil and platelet engraftment post transplantation. There were 156 patients randomized and 134 patients' data analyzed. Pegfilgrastim 6 mg day 7 produced highest percentage of successful mobilization, 34 out of 48 (70.8%) analyzed patients, followed by daily filgrastim, 28 out of 44 (63.6%) and day 3 pegfilgrastim, 20 out of 42 (47.6%) (p = 0.075). Pegfilgrastim day 7 and daily filgrastim reported 1.48 (p = 0.014) and 1.49 (p = 0.013) times higher successful mobilization rate respectively as compared to pegfilgrastim day 3 after adjusting for disease, gender and exposure to myelotoxic agent. Multiple myeloma patients were three times more likely to achieve successful mobilization as compared to acute leukemia or lymphoma patients. Pegfilgrastim avoided the overshoot of white cells compared to filgrastim. There was no difference in the duration of both white cells and platelet recovery post transplantation between the three interventional arms.
    Matched MeSH terms: Lymphoma
  7. Low SK, Zayan AH, Istanbuly O, Nguyen Tran MD, Ebied A, Mohamed Tawfik G, et al.
    Leuk Lymphoma, 2019 12;60(14):3406-3416.
    PMID: 31322026 DOI: 10.1080/10428194.2019.1633636
    Primary pulmonary lymphomas (PPLs) are rare lymphoproliferative malignancies arising from the lungs. The prognostic factors and optimal management of PPL have not been clearly defined due to its rarity. This study sought to characterize the significant prognostic factors and develop a validated nomogram for individualized prediction of survival outcomes in patients with PPL. A total of 2325 patients diagnosed with PPL between 1983 and 2010 were identified using the Surveillance, Epidemiology, and End Results (SEER) database. Older age at diagnosis, males, Hispanic race, non-marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue histology, Ann Arbor stage IV were significantly associated with worse OS on multivariable analysis. All treatment modalities, including chemotherapy, surgery, and radiotherapy were independent predictors of survival on univariable analysis. The nomogram built demonstrated good discriminative ability and calibration, with the C-index of 0.690 and 0.730 in the training and validation cohorts, respectively.
    Matched MeSH terms: Lymphoma, B-Cell, Marginal Zone
  8. Ariffin H, Muthukkumaran T, Stanslas J, Sabariah AR, Veerasekaran N, Lin HP
    Leuk Lymphoma, 2005 Aug;46(8):1233-7.
    PMID: 16085568
    We report the clinical features and in vitro chemosensitivity assay findings of a 13-year-old girl who developed secondary B-cell acute lymphoblastic leukemia (ALL) 7 years after a diagnosis of Wilms' tumor. The patient was treated using the Berlin - Frankfurt - Muenster (BFM) ALL chemotherapy protocol with poor response to initial therapy before succumbing to sepsis. An in vitro chemosensitivity assay on her peripheral blood lymphoblasts was performed while she was undergoing induction therapy and showed a high level of resistance to drugs commonly used for ALL therapy, e.g. steroids, anthracyclines, vincristine and L-asparaginase. The mechanism of chemoresistance was not elicited, but was probably not related to P-glycoprotein (P-gp) over-expression. We believe that the in vitro chemosensitivity assay is a good indicator of cellular response to chemotherapy and may provide reliable information for the basis of the selection of drugs to be used for the treatment of similarly rare patients rather than relying on "standard" protocols.
    Matched MeSH terms: Burkitt Lymphoma/complications*; Burkitt Lymphoma/diagnosis; Burkitt Lymphoma/drug therapy
  9. Faridah S, Siti Asma' H, Zeti NS, Tuan Noorkorina TK, Intan Baiduri B, Azura H
    Med J Malaysia, 2021 03;76(2):248-250.
    PMID: 33742638
    Mycobacteria mucogenicum (M. mucogenicum) is a rarely isolated pathogen. It has emerged as a significant pathogen in immunocompromised patients including those with cancer, organ transplant, or patients on immunosuppressive medication. Chemotherapy may reduce the ability of the bone marrow of these to respond to infection, and patients will be at risk for neutropenic sepsis, which leads to fatal complications. Here, we report a case of an 18-year-old boy was seen at Hospital Raja Perempuan Zainab II, Kelantan with acute lymphoblastic leukaemia (ALL) who presented with catheter-related bloodstream infection (CRBSI) caused by M. mucogenicum. He succumbed due to neutropenic sepsis with multiorgan failure.
    Matched MeSH terms: Precursor Cell Lymphoblastic Leukemia-Lymphoma
  10. Mohammad Fauzan Zainudin, Ummu Afifah Fadzir, Athirah Rosdi, Muhammad Farid Johan, Ridzwan Hashim, Ridhwan Abdul Wahab, et al.
    MyJurnal
    Acute lymphoblastic leukemia (ALL) is the most common leukemia subtypes among paediatrics in Malaysia. Although treatment options are available but some patients remain incurable, some undergo relapse and many experiences adverse effects by the conventional therapies. Thus, we aim to investigate possible treatment alternative by studying the antileukemogenesis properties of concentrated Nypa fruticans sap called nisaan by focusing on adiponectin expression.
    Our study model was CCRF-CEM, an acute lymphoblastic leukemia cell lines. The cells were treated with nisaan at a range of concentration and treated for 24, 48 and 72 hours followed by determination of the leukemic cells viability using tryphan blue method. Effective nisaan concentrations that significantly reduced the cells viability were again treated to the cells followed by determination of the cell proliferation using BrdU colorimetric kit and adiponectin level using adiponectin ELISA kit.
    The results showed that, increase concentration of nisaan treatment reduced the cells viability and cells proliferation and enhance the adiponectin level in the leukemic cells.
    This preliminary data suggest that Nypa fruticans might has the antileukemogenesis effect on acute lymphoblastic cells by regulating the adiponectin expression.
    Matched MeSH terms: Precursor Cell Lymphoblastic Leukemia-Lymphoma
  11. Daud, S.S., Ibrahim, K., Ariffin, H.
    JUMMEC, 2007;10(1):11-16.
    MyJurnal
    We aimed to establish a method for quantitative analysis of mixed haematopoietic chimerism based on microchip electrophoresis of selected molecular markers following PCR amplification for accurate monitoring of graft status post-transplantation. A 12-year-old girl with relapsed acute lymphoblastic leukaemia who underwent allogeneic bone marrow transplantation had qualitative chimerism analysis using short tandem repeat markers at three time points following the procedure. Her archived DNA samples were then used to test the ability to correlate her clinical course with changes in the quantity of donor chimerism at the different time points. Quantitative chimerism analysis was performed on the Agilent 2100 bioanalyser and donor-recipient ratios were calculated from generated electropherograms. Complete donor chimerism (98%) was demonstrated three weeks post- transplantation. Decreasing amount of donor chimerism to 24% was shown after three months and this concurred with clinical relapse. Following a second transplant, full donor chimerism was reestablished where donor chimerism rose to 100%. High resolution microchip electrophoresis could be useful in predicting the occurrence of increasing recipient chimerism which may herald impending relapse in patients while the disease burden is still low. This investigational approach may provide useful information for clinicians to select appropriate intervention strategies to ensure successful transplantation.
    Matched MeSH terms: Precursor Cell Lymphoblastic Leukemia-Lymphoma
  12. Azrina, M.R., Basri, M.N., Abdul Hadi, M., Fahmi, M.L., Asmarawati, M.Y., Ariff, O.
    MyJurnal
    High frequency oscillating ventilation (HFOV) provides a rescue therapy for patients with refractory hypoxaemia in severe acute respiratory distress syndrome (ARDS). HFOV utilizes high mean airway pressures to maintain an open lung and low tidal volumes at a high frequency that allows for adequate ventilation while at the same time preventing alveolar overdistension. This seems to be an ideal lung protective ventilation strategies to prevent ventilator-induced lung injury (VILI)2. We reported a case of severe extrapulmonary ARDS secondary to acute lymphoblastic leukaemia responding to the use of HFOV.
    Matched MeSH terms: Precursor Cell Lymphoblastic Leukemia-Lymphoma
  13. Chua LL, Rajasuriar R, Azanan MS, Abdullah NK, Tang MS, Lee SC, et al.
    Microbiome, 2017 03 20;5(1):35.
    PMID: 28320465 DOI: 10.1186/s40168-017-0250-1
    BACKGROUND: Adult survivors of childhood cancers such as acute lymphoblastic leukemia (ALL) have health problems that persist or develop years after cessation of therapy. These late effects include chronic inflammation-related comorbidities such as obesity and type 2 diabetes, but the underlying cause is poorly understood.

    RESULTS: We compared the anal microbiota composition of adult survivors of childhood ALL (N = 73) with healthy control subjects (N = 61). We identified an altered community with reduced microbial diversity in cancer survivors, who also exhibit signs of immune dysregulation including increased T cell activation and chronic inflammation. The bacterial community among cancer survivors was enriched for Actinobacteria (e.g. genus Corynebacterium) and depleted of Faecalibacterium, correlating with plasma concentrations of IL-6 and CRP and HLA-DR+CD4+ and HLA-DR+CD8+ T cells, which are established markers of inflammation and immune activation.

    CONCLUSIONS: We demonstrated a relationship between microbial dysbiosis and immune dysregulation in adult ALL survivors. These observations suggest that interventions that could restore microbial diversity may ameliorate chronic inflammation and, consequently, development of late effects of childhood cancer survivors.

    Matched MeSH terms: Precursor Cell Lymphoblastic Leukemia-Lymphoma/complications; Precursor Cell Lymphoblastic Leukemia-Lymphoma/immunology*; Precursor Cell Lymphoblastic Leukemia-Lymphoma/microbiology*
  14. Mohd. Ridah L.J., Ismail A., A. Talib N., Muhammad N., Hussain F.A., Zainuddin N.
    MyJurnal
    Introduction: Methylation of promoter region of p16 leading to gene silencing has been implicated ina wide range of malignancies including lymphomas. In diffuse large B cell lymphoma (DLBCL) particularly, a varying percentage of epigenetic inactivation of p16 promoter region was observed ranging from 16 -54%. However, quantitative analysis of p16 promoter methylation in DLBCL has not been extensively studied in Malaysia. Objective: This study aims to quantitatively analyse p16 methylation in DLBCL samples using pyrosequencing technique. Methods: Genomic DNA was extracted from 16 formalin-fixed paraffin-embedded lymphoma tissue blocks from patients diagnosed with DLBCL. Samples were retrieved from Hospital Tengku Ampuan Afzan, Pahang and Hospital Universiti Sains Malaysia, Kelantan. Primers were designed to amplify bisulfite-treated DNA targeting p16 promoter region. Methylation status of 7 CpG sites was determined by pyrosequencing. Results: All the 16 samples studied showed promoter methylation of p16. The range of mean methylation percentage was between 18 to 81%. Conclusion: The present study has successfully measured the level of methylation of p16 in all 7 CpG sites despite the limitation in sample size. Since p16 methylation is a common event in our series of DLBCL cases, it is worth including a larger sample size in future studies to increase the chance of finding a significant correlation with clinical parameters.
    Matched MeSH terms: Lymphoma
  15. Norafiza Zainuddin, Lailatul Jalilah Mohd Ridah, Aqilah Nabihah Omar, Norlelawati A. Talib, Naznin Muhammad, Faezahtul Arbaeyah Hussain
    MyJurnal
    MGMT (O6
    -Methylguanine-DNA Methyltransferase) suppresses tumor development by removing alkyl adduct, while
    SPOCK2 (SPARC/Osteonectin CWCV and Kazal-like domains proteoglycan) abolishes the inhibition of membrane-type
    matrix metalloproteinases (MT-MMP) which leads to angiogenesis. Hence, MGMT methylation may initiate malignant cells
    transformation. In contrast, SPOCK2 methylation is hypothesized not to be a common event in diffuse large B-cell lymphoma
    (DLBCL). In this study, we examined the methylation status of MGMT and SPOCK2 in DLBCL as in Malaysia the information
    is extremely lacking. A total of 88 formalin-fixed paraffin-embedded tissue of patients diagnosed with DLBCL from the
    year 2006 to 2013 were retrieved from Hospital Universiti Sains Malaysia, Kelantan and Hospital Tengku Ampuan Afzan,
    Pahang. Methylation-specific polymerase chain reaction (MSP) was used to examine the methylation status of both genes.
    Interestingly, methylation of MGMT was detected in all the 88 DLBCL samples, whereas SPOCK2 was found to be methylated
    in 83 of 88 (94.3%) DLBCL cases. Our study showed a remarkably high percentage of promoter methylation of both
    MGMT and SPOCK2 genes. Our finding also negates initial expectation that SPOCK2 methylation would be an uncommon
    event in the majority of DLBCL cases. This study has shown a very high percentage of promoter methylation of MGMT and
    SPOCK2 in the DLBCL cases studied by MSP, using archival lymphoma tissues. Nonetheless, additional research is needed
    to quantitatively evaluate MGMT and SPOCK2 methylation, and to analyse gene expression and/or protein expression in
    order to further understand the role of MGMT and SPOCK2 methylation in the pathogenesis of DLBCL.
    Matched MeSH terms: Lymphoma, Large B-Cell, Diffuse
  16. Tee Evelyn Wy Yap CT, Evelyn Yap WY
    Med J Malaysia, 2019 Oct;74(5):441-442.
    PMID: 31649225
    Subcutaneous Panniculitis-like T-cell Lymphoma (SPTL) is a rare cutaneous neoplasm of mature cytotoxic T cells, first described in 1991 by Gonzalez et al. The incidence of SPTL in Asian countries ranges from 2.3% to 3%. In Malaysia, only 5 cases were reported from 2001 to 2004 in Hospital Kuala Lumpur, Malaysia. SPTL typically presents as skincoloured or erythematous subcutaneous nodules, most often on the extremities and trunk, but it can also involve the face, back and neck. Diagnosis of SPTL is made based on correlation of clinical findings and subcutaneous tissue biopsy along with immunohistochemical staining patterns.
    Matched MeSH terms: Lymphoma, T-Cell
  17. Zhang Y, Lee S, Xu W
    Biochem Biophys Res Commun, 2020 04 16;524(4):1018-1024.
    PMID: 32063363 DOI: 10.1016/j.bbrc.2020.02.021
    Pten deletion in the hematopoietic stem cells (HSC) causes a myeloproliferative disorder, which may subsequently develop into a T-cell acute lymphoblastic leukemia (T-ALL). β-catenin expression was dramatically increased in the c-KitmidCD3+Lin- leukemia stem cells (LSC) and was critical for T-ALL development. Therefore, the inactivation of β-catenin in LSC may have a potential to eliminate the LSC. In this study, we investigated the mechanism of enhancement of the β-catenin expression and subsequently used a drug to inactivate β-catenin expression in T-ALL. Western blot (WB) analysis revealed an increased level of β-catenin in the leukemic cells, but not in the pre-leukemic cells. Furthermore, the WB analysis of the thymic cells from different stages of leukemia development showed that increased expression of β-catenin was not via the pS9-GSK3β signaling, but was dependent on the pT308-Akt activation. Miltefosine (Hexadecylphosphocholine) is the first oral anti-Leishmania drug, which is a phospholipid agent and has been shown to inhibit the PI3K/Akt activity. Treatment of the PtenΔ/Δ leukemic mice with Miltefosine for different durations demonstrated that the pT308-Akt and the β-catenin expressions were inhibited in the leukemia blast cells. Miltefosine treatment also suppressed the TGFβ1/Smad3 signaling pathway. Analysis of TGFβ1 in the sorted subpopulations of the blast cells showed that TGFβ1 was secreted by the CD3+CD4- subpopulation and may exert effects on the subpopulations of both CD3+CD4+ and CD3+CD4- leukemia blast cells. When a TGFβR1 inhibitor, SB431542 was injected into the PtenΔ/Δ leukemic mice, the Smad3 and β-catenin expressions were down-regulated. On the basis of the results, we conclude that Miltefosine can suppress leukemia by degrading β-catenin through repression of the pT308-Akt and TGFβ1/Smad3 signaling pathways. This study demonstrates a possibility to inhibit Pten loss-associated leukemia genesis via targeting Akt and Smad3.
    Matched MeSH terms: Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/drug therapy*; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/genetics; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/metabolism
  18. Oh L, Hainaut P, Blanchet S, Ariffin H
    BMC Cancer, 2020 Feb 10;20(1):110.
    PMID: 32041553 DOI: 10.1186/s12885-020-6599-8
    BACKGROUND: TP53 mutations occur in only about 3% of primary and 10-20% of relapse B-cell precursor acute lymphoblastic leukaemia (BCP-ALL). However, alternative mechanisms may contribute to functionally impairing the p53 pathway in the absence of a mutation. Candidate mechanisms include overexpression of p53 mRNA variants encoding either dominant-negative p53 protein isoforms such as Delta40p53 and Delta133p53, or modulatory isoforms such as p53beta, which counteract the effects of Delta133p53 on replicative senescence in T-lymphocytes.

    METHODS: We used semi-quantitative reverse-transcriptase PCR (RT-PCR) and Western blot to investigate the expression of full length p53 (TAp53), Delta40p53, Delta133p53 or p53beta in diagnostic marrow from a clinical cohort of 50 BCP-ALL patients without TP53 mutation (29 males and 21 females, age range 2-14 years) and in the bone marrow cells of 4 healthy donors (used as controls).

    RESULTS: Irrespective of isoforms, levels of p53 mRNA were low in controls but were increased by 2 to 20-fold in primary or relapse BCP-ALL. TAp53 was increased in primary BCP-ALL, Delta40p53 was elevated in relapse BCP-ALL, whereas Delta133p53 and p53beta were increased in both. Next, mRNA levels were used as a basis to infer the ratio between protein isoform levels. This inference suggested that, in primary BCP-ALL, p53 was predominantly in active oligomeric conformations dominated by TAp53. In contrast, p53 mostly existed in inactive quaternary conformations containing ≥2 Delta40 or Delta133p53 in relapse BCP-ALL. Western blot analysis of blasts from BCP-ALL showed a complex pattern of N-terminally truncated p53 isoforms, whereas TAp53beta was detected as a major isoform. The hypothesis that p53 is in an active form in primary B-ALL was consistent with elevated level of p53 target genes CDKN1A and MDM2 in primary cases, whereas in relapse BCP-ALL, only CDKN1A was increased as compared to controls.

    CONCLUSION: Expression of p53 isoforms is deregulated in BCP-ALL in the absence of TP53 mutation, with increased expression of alternative isoforms in relapse BCP-ALL. Variations in isoform expression may contribute to functional deregulation of the p53 pathway in BCP-ALL, specifically contributing to its down-regulation in relapse forms.

    Matched MeSH terms: Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics*; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/pathology*; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/therapy
  19. Sivaramakarthikeyan R, Iniyaval S, Saravanan V, Lim WM, Mai CW, Ramalingan C
    ACS Omega, 2020 May 05;5(17):10089-10098.
    PMID: 32391496 DOI: 10.1021/acsomega.0c00630
    Synthesis of a series of benzimidazole-ornamented pyrazoles, 6a-6j has been obtained from arylhydrazine and aralkyl ketones via a multistep synthetic strategy. Among them, a hybrid-possessing para-nitrophenyl moiety connected to a pyrazole scaffold (6a) exerted the highest anti-inflammatory activity, which is superior to the standard, diclofenac sodium. While executing the 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity, a hybrid-possessing para-bromophenyl unit integrated at the pyrazole structural motif (6i) exhibited the highest activity among the hybrids examined. Besides, evaluation of anticancer potency of the synthesized hybrids revealed that the one containing a para-fluorophenyl unit tethered at the pyrazole nucleus (6h) showed the highest activity against both the pancreatic cancer cells (SW1990 and AsPCl) investigated. Considerable binding affinity between B-cell lymphoma and the hybrid, 6h has been reflected while performing molecular docking studies (-8.65 kcal/mol). The outcomes of the investigation expose that these hybrids could be used as effective intermediates to construct more potent biological agents.
    Matched MeSH terms: Lymphoma, B-Cell
  20. Hsum YW, Yew WT, Hong PL, Soo KK, Hoon LS, Chieng YC, et al.
    Planta Med, 2011 Jan;77(2):152-7.
    PMID: 20669087 DOI: 10.1055/s-0030-1250203
    Chronic inflammation is one of the predisposing factors for neoplastic transformation. Targeting inflammation through suppression of the pro-inflammatory pathway by dietary phytochemicals provides an important strategy for cancer prevention. Maslinic acid is a novel natural triterpenoid known to inhibit proliferation and induce apoptosis in some tumor cell lines. Although maslinic acid has cytotoxic and pro-apoptotic effects on cancer cells, the underlying mechanisms of its effects on the inflammatory pathway have yet to be elucidated. It has been reported that abnormal expression of pro-inflammatory enzyme cyclooxygenase-2 (COX-2) causes promotion of cellular proliferation, suppression of apoptosis, enhancement of angiogenesis and invasiveness. In the present study, the suppressive effect of maslinic acid on COX-2 expression and the binding activity of upstream transcription factors NF- κB and AP-1, which are known to regulate COX-2 transcriptional activation, were assessed using Raji cells. The anti-inflammatory action of maslinic acid was benchmarked against oleanolic acid and other standard drugs. Western blot analysis and electrophoretic mobility shift assay (EMSA) were employed to analyze COX-2 expression as well as NF- κB and AP-1 binding activity. Our results showed that maslinic acid suppresses COX-2 expression in a concentration-dependent manner. Likewise, the constitutive nuclear NF- κB (p65) activity as well as phorbol 12-myristate 13-acetate (PMA)- and sodium N-butyrate (SnB)-induced AP-1 binding activity in Raji cells were significantly reduced following treatment with maslinic acid. Since maslinic acid suppresses COX-2 expression in Raji cells at concentrations that also lowered the NF- κB (p65) and AP-1 binding activity, it is possible that the suppression of COX-2 by this natural triterpenoid might be achieved, at least in part, via the NF- κB and AP-1 signaling pathways.
    Matched MeSH terms: Lymphoma/metabolism; Lymphoma/pathology; Lymphoma/prevention & control
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