The role of microenvironment and immunity in drug response in leukemia

Leukemia is a cancer of the white blood cells, with over 54,000 new cases per year diagnosed worldwide and a 5-year survival rate below 60%. This highlights a need for research into the mechanisms behind its etiology and causes of therapy failure. The bone marrow microenvironment, in which adult stem cells are maintained in healthy individuals, has been implicated as a source of chemoresistance and disease relapse. Here the various ways that the microenvironment can contribute to the resistance and persistence of leukemia are discussed. The targeting of the microenvironment by leukemia cells to create an environment more suitable for cancer progression is described. The role of soluble factors, drug transporters, microvesicles, as well as the importance of direct cell–cell contact, in addition to the effects of inflammation and immune surveillance in microenvironment-mediated drug resistance are discussed. An overview of the clinical potential of translating research findings to patients is also provided. Understanding of and further research into the role of the bone marrow microenvironment in leukemia progression and relapse are crucial towards developing more effective treatments and reduction in patient morbidity

Prevalence of childhood asthma in Ulaanbaatar, Mongolia in 2009

Background: Bronchial asthma is a common but important chronic disease in children in all over the world. To take measures against prevalence of childhood asthma, many researchers have surveyed the actual statuses of childhood asthma in developed countries, but in most Asia–Pacific developing countries including Mongolia such surveys have never been sufficiently conducted until now. We have thought that this survey, though performed in 2009, will give important and meaningful information even now in taking measures to prevent prevailing bronchial asthma in children in Mongolia or the countries under similar statuses. Methods: The asthma prevalence and patient background information in Mongolian children aged 6–7 living in Ulaanbaatar were examined using a written questionnaire modified for their parents from that prepared by the International Study of Asthma and Allergies in Childhood (ISAAC). Results: The estimated prevalence of asthma in Mongolian children was 20.9%. The following 3 risk factors were found to be related to asthma: (1) having allergic rhinitis symptoms, (2) mothers' smoking, and (3) history of severe respiratory infection before 1-year-old. Conclusions: The asthma prevalence in Mongolian children was higher than that in the world and Asia–Pacific countries reported by ISAAC. The higher prevalence was probably attributable to households' (especially mothers) smoking in draft-free houses designed for the cold area and severe air-pollution due to rapid industrialization and urbanization in Mongolia. Smoking prohibition in the mother (including family members) and a reduction of exposure to air pollutants are urgently needed to prevent developing childhood asthma