324 research outputs found
Chemotherapy-Induced Cardiotoxicity: Overview of the Roles of Oxidative Stress
Chemotherapy-induced cardiotoxicity is a serious complication that poses a serious threat to life and limits the clinical use of various chemotherapeutic agents, particularly the anthracyclines. Understanding molecular mechanisms of chemotherapy-induced cardiotoxicity is a key to effective preventive strategies and improved chemotherapy regimen. Although no reliable and effective preventive treatment has become available, numerous evidence demonstrates that chemotherapy-induced cardiotoxicity involves the generation of reactive oxygen species (ROS). This review provides an overview of the roles of oxidative stress in chemotherapy-induced cardiotoxicity using doxorubicin, which is one of the most effective chemotherapeutic agents against a wide range of cancers, as an example. Current understanding in the molecular mechanisms of ROS-mediated cardiotoxicity will be explored and discussed, with emphasis on cardiomyocyte apoptosis leading to cardiomyopathy. The review will conclude with perspectives on model development needed to facilitate further progress and understanding on chemotherapy-induced cardiotoxicity
Hematology oncology practice in the Asia-Pacific APHCON survey results from the 6th international hematologic malignancies conference: bridging the gap 2015, Beijing, China
This report serves as a snapshot of the state-of-knowledge in the Asia Pacific (APAC) Hematology Oncology community, and establishes a baseline for longitudinal investigations to follow changes in best practices over time. The objective of this study was to understand the approach to hematologic diseases, common standards of care and best practices, issues that remain controversial or debated, and educational or resource gaps that warrant attention. We used mobile application to disseminate and distribute questionnaires to delegates during the 6th international hematologic malignancies conference hosted by the APAC Hematology Consortium at Beijing, China. User responses were collected in an anonymous fashion. We report survey results in two ways: the overall responses, and responses as stratified between Chinese physicians and 'Other' represented nationalities. Overall geographical concordance in survey responses was positive and strong. Perhaps more interesting than instances of absolute agreement, these data provide a unique opportunity to identify topics in which physician knowledge or opinions diverge. We assigned questions from all modules to broad categories of: patient information; diagnosis; treatment preference; transplantation; and general knowledge/opinion. On average, we observed a geographic difference of 15% for any particular answer choice, and this was fairly constant across survey modules. These results reveal utility and need for widespread and ongoing initiatives to assess knowledge and provide evidence-based education in real time. The data will be made more valuable by longitudinal participation, such that we can monitor changes in the state of the art over time.published_or_final_versio
Induction Of Cancer-Associated Fibroblast-Like Cells By Carbon Nanotubes Dictates Its Tumorigenicity
Tumor microenvironment has been recognized as a key determinant of tumor formation and metastasis, but how tumor microenvironment is affected by nanomaterials is essentially unknown. Here, we investigated whether carbon nanotubes (CNTs), a widely used nanomaterial with known carcinogenic potential, can affect cancer-associated fibroblasts (CAFs), which are a key component of tumor microenvironment that provides necessary support for tumor growth. We show for the first time that single-walled CNT and to a lesser extent multi-walled and its COOH-functionalized form induced CAF-like cells, which are non-tumorigenic in animals, but promote tumor growth of human lung carcinoma and CNT-transformed lung epithelial cells. The mechanism by which CNT-induced CAF-like cells promote tumor growth involved the acquisition of cancer stem cells (CSCs) in cancer population. Gene knockdown experiments showed that an expression of podoplanin on CAF-like cells is essential for their effects, indicating the functional role of CAF-like cells and podoplanin in CNT tumorigenic process. Our findings unveil a novel mechanism of CNT-induced carcinogenesis through the induction of CAFlike cells that support CSCs and drive tumor formation. Our results also suggest the potential utility of podoplanin as a mechanism-based biomarker for rapid screening of carcinogenicity of CNTs and related nanomaterials for their safer design
OGT and OGA gene-edited human induced pluripotent stem cells for dissecting the functional roles of O-GlcNAcylation in hematopoiesis
Hematopoiesis continues throughout life to produce all types of blood cells from hematopoietic stem cells (HSCs). Metabolic state is a known regulator of HSC self-renewal and differentiation, but whether and how metabolic sensor O-GlcNAcylation, which can be modulated via an inhibition of its cycling enzymes O-GlcNAcase (OGA) and O-GlcNAc transferase (OGT), contributes to hematopoiesis remains largely unknown. Herein, isogenic, single-cell clones of OGA-depleted (OGAi) and OGT-depleted (OGTi) human induced pluripotent stem cells (hiPSCs) were successfully generated from the master hiPSC line MUSIi012-A, which were reprogrammed from CD34+ hematopoietic stem/progenitor cells (HSPCs) containing epigenetic memory. The established OGAi and OGTi hiPSCs exhibiting an increase or decrease in cellular O-GlcNAcylation concomitant with their loss of OGA and OGT, respectively, appeared normal in phenotype and karyotype, and retained pluripotency, although they may favor differentiation toward certain germ lineages. Upon hematopoietic differentiation through mesoderm induction and endothelial-to-hematopoietic transition, we found that OGA inhibition accelerates hiPSC commitment toward HSPCs and that disruption of O-GlcNAc homeostasis affects their commitment toward erythroid lineage. The differentiated HSPCs from all groups were capable of giving rise to all hematopoietic progenitors, thus confirming their functional characteristics. Altogether, the established single-cell clones of OGTi and OGAi hiPSCs represent a valuable platform for further dissecting the roles of O-GlcNAcylation in blood cell development at various stages and lineages of blood cells. The incomplete knockout of OGA and OGT in these hiPSCs makes them susceptible to additional manipulation, i.e., by small molecules, allowing the molecular dynamics studies of O-GlcNAcylation
A High-Throughput, Three-Dimensional Multiple Myeloma Model Recapitulating Tumor-Stroma Interactions for CAR-Immune Cell-Mediated Cytotoxicity Assay
Sudjit Luanpitpong,1– 3 Montira Janan,1– 3 Jirarat Poohadsuan,1 Napachai Rodboon,1 Parinya Samart,1 Sasitorn Rungarunlert,4 Surapol Issaragrisil1,5,6 1Siriraj Center of Excellence for Stem Cell Research, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; 2Siriraj Cell Factory for Cancer Immunotherapy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; 3Blood Products and Cellular Immunotherapy Research Group, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; 4Department of Preclinic and Applied Animal Science, Faculty of Veterinary Science, Mahidol University, Nakhon Pathom, Thailand; 5Division of Hematology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; 6BDMS Center of Excellence for Hematology, Wattanosoth Cancer Hospital, Bangkok, ThailandCorrespondence: Sudjit Luanpitpong; Surapol Issaragrisil, Siriraj Center of Excellence for Stem Cell Research, Faculty of Medicine Siriraj Hospital, Mahidol University, 2 Siriraj Hospital, Bangkok, 10700, Thailand, Tel +6624192907 ; +6624194446, Email [email protected]; [email protected]: Multiple myeloma (MM) is characterized by an excessive proliferation of clonal plasma cells in the bone marrow (BM). Components in BM niche contribute to the immunosuppressive tumor microenvironment (TME), but three-dimensional (3D) MM models that recreate the complex TME and enable high-throughput cytotoxicity assay of chimeric antigen receptor (CAR)-engineered immune cells are still lacking.Methods: Stable, luciferase (Luc)-labeled target MM cells were generated using Luc/RFP dual reporter system to track MM growth. 3D spheroids were formed in a 96-well plate in the presence or absence of cancer-associated fibroblast (CAF)-like stromal cells activated by MM-derived conditioned medium and the cytotoxicity of CAR-immune cells, which were represented by third-generation anti-CD138 CAR-NK-92 cells, was evaluated by luciferase assay using a multimode microplate reader. Immune cell infiltration was visualized under a fluorescence microscope by using multiple fluorescent dyes.Results: We first showed that luciferase assay provides a relatively simple and robust means to specifically monitor Luc-labeled tumor cell growth in a coculture system, allowing the high-throughput assessment of CAR-immune cytotoxicity. Through this assay, we demonstrated that CAF-like stromal cells impaired NK cell effector function in 2D culture and 3D spheroids, likely via paracrine signaling and physical barrier function. Importantly, we showed that 3D spheroids consisting of MM cells and CAF-like stromal cells provide a more comprehensive, physiologically relevant immuno-oncology model. Our established model could also be used to investigate the trafficking and infiltration of immune cells into the core of spheroids. Herein, we showed that CAR incorporation did improve the ability of NK cells to infiltrate 3D spheroids.Conclusion: Our established 3D spheroid model, which partially recapitulates the complex TME with immunosuppressive environment, is suitable for high-throughput screening of CAR-immune cytotoxicity and could be important in accelerating immuno-oncology drug discovery for MM since there is a pressing need to establish innovative CAR-immune cells.Keywords: 3D culture, multiple myeloma, tumor microenvironment, stromal cells, cancer-associated fibroblasts, CA
Long-term benefits and risks of frontline nilotinib vs imatinib for chronic myeloid leukemia in chronic phase: 5-year update of the randomized ENESTnd trial
Serious fungal infections in Thailand
The burden of serious fungal infection in Thailand is increasing but data regarding its incidence and prevalence are lacking. In this study we aimed to estimate the burden of serious fungal diseases in Thailand based on the size of the populations at risk and available epidemiological databases. Data derived from The Bureau of Epidemiology, Department of Disease Control, Thai Ministry of Public Health, World Health Organisation, international and local reports, and some unreported data were used. When no data existed, risk populations were used to estimate frequencies of fungal infections, using previously described methodology by LIFE. Recurrent vulvovaginal candidiasis (>4 episodes per year) is estimated to occur in 3,310 per 100,000 population. Using a previously described rate that 14/10,000 admissions are with fungaemia and 94% of those are Candida, we estimated 8,650 patients with candidaemia. The prevalence of chronic pulmonary aspergillosis is relatively high with a total of 19,044, approximately half subsequent to pulmonary tuberculosis. Invasive aspergillosis is estimated to affect 941 patients following leukaemia therapy, transplantations, and chronic obstructive pulmonary disease, approximately 1.4/100,000. In addition, allergic bronchopulmonary aspergillosis and severe asthma with fungal sensitisation were estimated at approximately 58.4/100,000 and 77/100,000, respectively. Given approximately 8,134 new cases of AIDS annually, cryptococcal meningitis, Pneumocystis pneumonia, and Talaromyces marneffei infection are estimated at 1.9/100,000, 2.6/100,000, and 0.3/100,000, respectively. The present study indicates that about 1.93% (1,254,562) of the population is affected by serious fungal infections. Owing to the lack of data, reports, and statistics, the number of patients with mycoses in Thailand can only be estimated
Nilotinib versus imatinib for newly diagnosed chronic myeloid leukemia
BACKGROUND: Nilotinib has been shown to be a more potent inhibitor of BCR-ABL than imatinib. We evaluated the efficacy and safety of nilotinib, as compared with imatinib, in patients with newly diagnosed Philadelphia chromosome–positive chronic myeloid leukemia (CML) in the chronic phase. METHODS: In this phase 3, randomized, open-label, multicenter study, we assigned 846 patients with chronic-phase Philadelphia chromosome–positive CML in a 1:1:1 ratio to receive nilotinib (at a dose of either 300 mg or 400 mg twice daily) or imatinib (at a dose of 400 mg once daily). The primary end point was the rate of major molecular response at 12 months. RESULTS: At 12 months, the rates of major molecular response for nilotinib (44% for the 300-mg dose and 43% for the 400-mg dose) were nearly twice that for imatinib (22%) (P<0.001 for both comparisons). The rates of complete cytogenetic response by 12 months were significantly higher for nilotinib (80% for the 300-mg dose and 78% for the 400-mg dose) than for imatinib (65%) (P<0.001 for both comparisons). Patients receiving either the 300-mg dose or the 400-mg dose of nilotinib twice daily had a significant improvement in the time to progression to the accelerated phase or blast crisis, as compared with those receiving imatinib (P = 0.01 and P = 0.004, respectively). No patient with progression to the accelerated phase or blast crisis had a major molecular response. Gastrointestinal and fluid-retention events were more frequent among patients receiving imatinib, whereas dermatologic events and headache were more frequent in those receiving nilotinib. Discontinuations due to aminotransferase and bilirubin elevations were low in all three study groups. CONCLUSIONS: Nilotinib at a dose of either 300 mg or 400 mg twice daily was superior to imatinib in patients with newly diagnosed chronic-phase Philadelphia chromosome–positive CML. (ClinicalTrials.gov number, NCT00471497.
Comparison of endothelial progenitor cell function in type 2 diabetes with good and poor glycemic control
<p>Abstract</p> <p>Background</p> <p>Endothelial progenitor cells (EPCs) play an important role in vascular repair and a decrease in the number of EPCs is observed in type 2 diabetes. However, there is no report on the change of EPCs after glycemic control. This study therefore aimed to investigate the EPC number and function in patients with good and poor glycemic control.</p> <p>Methods</p> <p>The number of EPCs was studied using flow cytometry by co-expression of CD34 and VEGFR2. The EPCs were cultured and characterized by the expression of UEA-I, CD34, VEGFR2, vWF and Dil-Ac-LDL engulfment, as well as the ability to form capillary-like structures. An <it>in vitro </it>study on the effect of hyperglycemia on the proliferation and viability of the cultured EPCs was also performed.</p> <p>Results</p> <p>The number of EPCs in type 2 diabetes was significantly decreased compared with healthy controls and there was an inverse correlation between the EPC numbers and plasma glucose, as well as HbA1<sub>C</sub>. The number and function of EPCs in patients with good glycemic control were recovered compared with those with poor glycemic control. When glucose was supplemented in the culture <it>in vitro</it>, there was a negative effect on the proliferation and viability of EPCs, in a dose-dependent manner, whereas the enhancement of apoptosis was observed.</p> <p>Conclusion</p> <p>There was EPC dysfunction in type 2 diabetes which might be improved by strict glycemic control. However, the circulating EPC number and proliferative function in patients with good glycemic control did not reach the level in healthy controls.</p
Hematopoietic progenitor cells in the blood and bone marrow in various hematologic disorders
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