Compounds in cigarette smoke induce EGR1 expression via the AHR, resulting in apoptosis and COPD

Chronic obstructive pulmonary disease (COPD) is a major cause of mortality worldwide, and pulmonary epithelial cell apoptosis is regarded as one of the most important factors in its pathogenesis. Here, we examined the molecular mechanisms of apoptosis caused by cigarette smoke (CS). In the normal bronchial epithelium cell line BEAS-2B, a CS extract markedly induced apoptosis together with transient early growth response 1 (EGR1) protein expression, which is activated over time via the aryl hydrocarbon receptor (AHR). The CS extract-induced apoptosis decreased cell count of BEAS-2B cells and was significantly reversed by knockdown of either EGR1 or AHR. In vivo, the CS extract caused alveolar wall destruction, mimicking COPD, 1 week after intrathoracic injection. Bronchoalveolar lavage fluid (BALF) from the CS extract-treated mice contained massive numbers of apoptotic epithelial cells. Furthermore, it was found that aminoanthracene induced EGR1 expression and cell apoptosis. By contrast, the AHR antagonist stemregenin 1 (SR1) restored apoptosis upon CS treatment. These results suggest that aryl hydrocarbons, such as aminoanthracene, induce EGR1 expression via the AHR, resulting in cell apoptosis and that this can be prevented by administration of an antagonist of AHR.

High prevalence of soil-transmitted helminth infections in Myanmar schoolchildren

Background

Achieving the elimination of soil-transmitted helminth (STH) infections requires a sufficient understanding of the current epidemiological status of STH endemicity. We aimed to examine the status of STH in Myanmar – a country with the eighth highest STH prevalence in the world, 10 years after instigation of the national deworming programme.

Methods

In August 2016 we screened for STH infections using Kato Katz (KK) microscopy and real-time PCR (qPCR) in schoolchildren from the Bago Region township of Phyu, a STH sentinel site in Myanmar. Ten schools were randomly selected, and one stool sample each from a total of 264 students was examined. Prevalence and intensity of infection were calculated for each STH.

Results

High prevalence of STH was identified in the study area with 78.8% of the schoolchildren infected with at least one STH by qPCR, and 33.3% by KK. The most prevalent STH was Trichuris trichiura, diagnosed by both KK (26.1%) and qPCR (67.1%), followed by Ascaris lumbricoides (15.5% KK; 54.9% qPCR). No hookworm infections were identified by KK; however, the qPCR analysis showed a high prevalence of Ancylostoma sp. infection (29.6%) with few Necator americanus (1.1%) infections.

Conclusions

Despite bi-annual deworming of schoolchildren in the fourth-grade and below, STH prevalence remains stubbornly high. These results informed the expansion of the Myanmar National STH control programme to include all school-aged children by the Ministry of Health and Sports in 2017, however further expansion to the whole community should be considered along with improving sanitation and hygiene measures. This would be augmented by rigorous monitoring and evaluation, including national prevalence surveys.

Nuclear Expression of Pygo2 Correlates with Poorly Differentiated State Involving c-Myc, PCNA and Bcl9 in Myanmar Hepatocellular Carcinoma

In Myanmar, hepatocellular carcinoma (HCC) is commonly seen in young adult and associated with poor prognosis, while the molecular mechanisms that characterize HCC in Myanmar are unknown. As co-activation of Wnt/β-catenin signaling and c-Myc (Myc) are reported to associate with malignancy of HCC, we immunohistochemically investigated the expression of Pygo2 and Bcl9, the co-activators of the Wnt/β-catenin signaling, Myc and PCNA in 60 cases of Myanmar HCC. Pygo2 expression was confirmed by in situ hybridization. The signal intensity was measured by image analyzer and then statistically analyzed. As a result, the expression of Pygo2 was significantly higher in HCC compared to normal liver tissue and the nuclear signal was the most intense in poorly differentiated HCC. Cytoplasmic Bcl9 was expressed in the normal liver tissue but decreased in HCC with the progression of histopathological grade. Myc was significantly higher in poorly differentiated HCC, whereas PCNA labeling index increased with the progression of histopathological grade. Nuclear Pygo2 showed strong correlation with nuclear Myc (P < 0.01) and PCNA (P < 0.001), and inversely correlated with cytoplasmic Bcl9 (P < 0.01). Our results suggested Wnt/β-catenin and Myc signaling is commonly activated in Myanmar HCC and that the correlative upregulation of nuclear Pygo2 and Myc characterizes the malignant features of HCC in Myanmar.

Immunohistochemical Mapping of Bcl9 Using Two Antibodies that Recognize Different Epitopes Is Useful to Characterize Juvenile Development of Hepatocellular Carcinoma in Myanmar

B-cell lymphoma 9 (Bcl9) is the core component of Wnt/β-catenin signaling and overexpressed in nuclei of various tumors, including hepatocellular carcinoma (HCC). However, the extent of Bcl9 expression relative to HCC differentiation stage and its functional aspects are poorly understood. In this study, we examined the expression pattern of Bcl9 immunohistochemically, using two anti-Bcl9 antibodies; one was a conventional polyclonal-antibody (anti-Bcl9^ABC) against amino acid no.800-900 of human-Bcl9, while the other (anti-Bcl9^BIO) was against amino acid no.50-200, covering Pygopus-binding sites of Bcl9. Immunohistochemistry using anti-Bcl9^BIO demonstrated distinctive staining in the cytoplasm, while the anti-Bcl9^ABC signal was detected in both cytoplasm and nuclei of HCC cells, reflecting different states of Bcl9 function because Pygopus-binding to Bcl9 is essential to exert its function together with β-catenin in nucleus. Quantitative analysis revealed a significantly higher immunohistochemical-score by anti-Bcl9^BIO in normal liver comparing various differentiation grades of HCC (P < 0.004), whereas no significant difference was noted with anti-Bcl9^ABC. Interestingly, immunohistochemical-score of anti-Bcl9^BIO in patients aged < 40 years was significantly lower than that of ≥ 40 years group (P < 0.01). The results indicated that anti-Bcl9^BIO detected cytoplasmic Bcl9, which does not bind to Pygopus suggesting it could be a useful indicator for development of HCC in young Myanmar patients.

Chloroquine efficacy for Plasmodium vivax in Myanmar in populations with high genetic diversity and moderate parasite gene flow

BACKGROUND

Plasmodium vivax malaria remains a major public health burden in Myanmar. Resistance to chloroquine (CQ), the first-line treatment for P. vivax, has been reported in the country and has potential to undermine local control efforts.

METHODS

Patients over 6 years of age with uncomplicated P. vivax mono-infection were enrolled into clinical efficacy studies in Myawaddy in 2014 and Kawthoung in 2012. Study participants received a standard dose of CQ (25 mg/kg over 3 days) followed by weekly review until day 28. Pvmdr1 copy number (CN) and microsatellite diversity were assessed on samples from the patients enrolled in the clinical study and additional cross-sectional surveys undertaken in Myawaddy and Shwegyin in 2012.

RESULTS

A total of 85 patients were enrolled in the CQ clinical studies, 25 in Myawaddy and 60 in Kawthoung. One patient in Myawaddy (1.2%) had an early treatment failure and two patients (2.3%) in Kawthoung presented with late treatment failures on day 28. The day 28 efficacy was 92.0% (95% CI 71.6-97.9) in Myawaddy and 98.3% (95% CI 88.7-99.8) in Kawthoung. By day 2, 92.2% (23/25) in Myawaddy and 85.0% (51/60) in Kawthoung were aparasitaemic. Genotyping and pvmdr1 CN assessment was undertaken on 43, 52 and 46 clinical isolates from Myawaddy, Kawthoung and Shwegyin respectively. Pvmdr1 amplification was observed in 3.2% (1/31) of isolates in Myawaddy, 0% (0/49) in Kawthoung and 2.5% (1/40) in Shwegyin. Diversity was high in all sites (H _E 0.855-0.876), with low inter-population differentiation (F _ST 0.016-0.026, P < 0.05).

CONCLUSIONS

Treatment failures after chloroquine were observed following chloroquine monotherapy, with pvmdr1 amplification present in both Myawaddy and Shwegyin. The results emphasize the importance of ongoing P. vivax drug resistance surveillance in Myanmar, particularly given the potential connectivity between parasite population at different sites.