Publications by authors named "Lih-Ann Li"

Lung adenocarcinoma is the most common type of lung cancer in women. Our previous studies demonstrated that 17β-estradiol (E2) promoted lung adenocarcinoma cell proliferation and tumor growth through estrogen receptor ERα. Transcriptomic analysis suggested that E2 potentiated TNFα-NFκB signaling in ERα-expressing lung adenocarcinoma cells.

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Indium tin oxide exposure poses a potential health risk, but the exposure assessment in occupational setting remains incomplete and continues to be a significant challenge. To this end, we investigated the association of work type, airborne indium concentration, respirable fraction of total indium, and cumulative indium exposure index (CEI) with the levels of plasma indium (P-In) and urinary indium (U-In) among 302 indium tin oxide target manufacturing and recycling workers in Taiwan. We observed that recycling-crushing produced the highest concentrations of total indium (area: 2084.

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Background: Although no human illness to date is confirmed to be attributed to engineered nanoparticles, occupational epidemiological studies are needed to verify the health effects of nanoparticles. This study used a repeated measures design to explore the potential adverse health effects of workers handling nanomaterials.

Methods: Study population was 206 nanomaterial-handling workers and 108 unexposed controls, who were recruited from 14 nanotechnology plants.

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Cigarette sidestream smoke particulate matter (CSSP) is a major source of airborne metals in the indoor environment. However, the health impacts of inhalation of CSSP-bound metals are rarely studied. In this study, we quantify the amount of 37 metals discharged through CSSP from a leading Taiwan brand of cigarette, Long Life.

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Berberine and the methylenedioxy ring-opening derivatives palmatine and jatrorrhizine are active ingredients in immunomodulatory plants, such as goldenseal. This study aimed to illustrate the effects of protoberberines on aryl hydrocarbon receptor (AhR) activation and cytochrome P450 (CYP) 1 in the estrogen receptor (ER)α(+) MCF-7 breast cancer cells. Among protoberberines at non-cytotoxic concentrations (≤10 μM), berberine had the most potent and statistically significant effects on AhR activation and CYP1A1/1A2/1B1 mRNA induction.

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Estrogen and secondhand smoke are key risk factors for nonsmoking female lung cancer patients who frequently have lung adenocarcinoma and show tumor estrogen receptor α (ERα) expression. We speculated that estrogen and secondhand smoke might cause harmful effects via ERα signaling. Our results showed that 17β-estradiol (E2), the primary form of endogenous estrogen, exacerbated proliferation, migration, and granzyme B resistance of lung adenocarcinoma cells in an ERα-dependent manner.

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Inhibition of 17α-hydroxylase/17,20-lyase (CYP17), which dictates the proceeding of androgen biosynthesis, is recommended as an effective treatment for androgen-dependent diseases. However, androgen depletion by selective CYP17 inhibition is accompanied with corticosteroid elevation, which increases risk of cardiovascular diseases. In this study, we evaluated the likelihood of polyphenols as a CYP17 inhibitor without cardiovascular complications.

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Fractional exhaled nitric oxide (FENO) measurement is a useful diagnostic test of airway inflammation. However, there have been few studies of FENO in workers exposed to nanomaterials. The purpose of this study was to examine the effect of nanoparticle (NP) exposure on FENO and to assess whether the FENO is increased in workers exposed to nanomaterials (NM).

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The aim of this study was to identify the health hazards and possible exposure surveillance markers of workers exposed to nanoparticles during manufacturing and application in comparison to a group of unexposed workers. For this longitudinal study, we recruited 158 nanomaterial-handling workers and 104 non-exposed workers from 14 manufacturing plants in Taiwan (baseline). Among them, 124 nanomaterial-handling workers and 77 unexposed workers were monitored 6 months later.

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Evidence suggests that estrogen affects the pulmonary response to carcinogenic pollutants, such as dioxins. In this study, we examined dioxin and estrogen signaling cross-talk in lung adenocarcinoma cell lines that were engineered to exhibit different aryl hydrocarbon receptor (AhR)/estrogen receptor (ER) α phenotypes. Data showed that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) weakly antagonized estrogen-activated ERα activity in cells expressing abundant ERα, but little AhR.

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We have demonstrated that aryl hydrocarbon receptor (AhR) is overexpressed in lung adenocarcinoma (AD). AhR is usually associated with heat shock protein 90 (Hsp90) in the cytoplasm. 17-Allylamino-17-demethoxygeldanamycin (17-AAG), an Hsp90 inhibitor, is currently under evaluation for its anticancer activity in clinical trials.

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Baicalein is a flavonoid, known to have anti-inflammatory and anti-cancer effects. As an aryl hydrocarbon receptor (AhR) ligand, baicalein at high concentrations blocks AhR-mediated dioxin toxicity. Because AhR had been reported to play a role in regulating the cell cycle, we suspected that the anti-cancer effect of baicalein is associated with AhR.

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Environmental cigarette smoke has been suggested to promote lung adenocarcinoma progression through aryl hydrocarbon receptor (AhR)-signaled metabolism. However, whether AhR facilitates metabolic activation or detoxification in exposed adenocarcinoma cells remains ambiguous. To address this question, we have modified the expression level of AhR in two human lung adenocarcinoma cell lines and examined their response to an extract of cigarette sidestream smoke particulates (CSSP).

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CYP11B1 catalyzes the final step of cortisol biosynthesis. The effects of flavonoids on transcriptional expression and enzyme activity of CYP11B1 were investigated using the human adrenocortical H295R cell model. All tested nonhydroxylated flavones including 3',4'-dimethoxyflavone, α-naphthoflavone, and β-naphthoflavone upregulated CYP11B1 expression and cortisol production, whereas apigenin and quercetin exhibited potent cytotoxicity and CYP11B1 repression at high concentrations.

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CYP11B1 and CYP11B2 responsible for the final steps of cortisol and aldosterone synthesis, respectively, are believed to be duplicate genes with distinctive promoters. Our sequence analysis uncovers that these two genes share great homology in the proximal upstream regions, but insertion of Alu and L1 elements drives promoters divergent. Each CYP11B promoter contains two Alu elements embedded in a truncated L1 element, breaking L1 into three disconnected fragments.

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Women have a higher risk of lung adenocarcinoma than men, suggesting that estrogen pathway may be involved in the pathogenesis of this cancer. This study was designed to determine whether ERα expression, estrogen levels, and endocrine disruptor exposure would influence tumor growth of lung adenocarcinoma cells using a xenograft model in which human lung adenocarcinoma cells with and without transgenic ERα expression were transplanted into female nude mice. Results showed that estrogen promoted tumor growth of ERα(+) lung adenocarcinoma cells but inhibited that of ERα(-) lung adenocarcinoma cells.

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Polycyclic aromatic hydrocarbons (PAHs) adsorbed on cigarette sidestream smoke particulates (CSSPs) have been regarded as important contributors to lung carcinogenesis in never smokers. However, limited information is available on PAH levels in cigarette sidestream smoke. Here we determine the concentrations of 22 PAHs, including 16 US EPA priority PAHs, in CSSPs generated from a high market-share domestic brand in Taiwan.

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Exposure to polychlorinated biphenyls (PCBs) disturbs many estrogen-mediated biochemical processes. PCBs may cause these abnormalities by altering expression of the aromatase gene CYP19. This study demonstrated that high concentrations of PCB126 increased basal CYP19 mRNA abundance in mouse testicular Leydig I-10 cells and human adrenocortical H295R cells.

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Toxicity of the polychlorinated biphenyls (PCBs) depends on their molecular structure. Mechanisms by prenatal exposure to a non-dioxin-like PCB, 2,2',3,4',5',6-hexachlorobiphenyl (PCB 132) that may act on reproductive pathways in male offspring are relatively unknown. The purpose was to determine whether epididymal sperm function and expression of apoptosis-related genes were induced or inhibited by prenatal exposure to PCB 132.

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Giving human adrenocortical H295R cells 14 mM KCl for 24 h significantly induced not only aldosterone biosynthesis but also cortisol biosynthesis. Pre-treating the cells with polychlorinated biphenyl 126 (PCB126) further increased potassium-induced aldosterone and cortisol productions in a dose-dependent manner, but all examined concentrations of PCB126 had little effect on the yields of precursor steroids progesterone and 17-OH-progesterone. Subsequent examinations revealed that CYP11B1 and CYP11B2 genes, responsible for the respective final steps of the cortisol and aldosterone biosynthetic pathways, exhibited increased responsiveness to PCB126 under high potassium.

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In the present study, we investigated the effect of arecoline, a major areca nut alkaloid, on the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced activation of cytochrome P4501A1 (CYP1A1) in a human hepatoma cell line Huh-7. We treated Huh-7 cells with 10nM TCDD in the presence of different concentrations of arecoline (50-300 microM). Our results indicated that arecoline attenuated the TCDD-induced CYP1A1 enzyme activation with an inhibitory effect on cell proliferation.

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The aim of this study was to examine the arsenic effect on activation of aryl hydrocarbon receptor (AhR)-mediated gene expression by 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) in human hepatoma cells. The human hepatoma Huh7 cells were treated with sodium arsenite (NaAsO2) from 0.5 to 20 microM for 24 h.

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Polychlorinated dibenzo-p-dioxins (PCDDs, dioxins), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) are environmental endocrine disruptors that have half-lives of 7-10 years in the human body and have toxicities that probably include carcinogenesis. A high ratio of 4-hydroxyl estradiol (4-OH-E2) to 2-hydroxyl estradiol (2-OH-E2) has been suggested as a potential biomarker for estrogen-dependent neoplasms. In this cohort study of maternal-fetal pairs, we examined the relationship of PCDD/PCDF and PCB exposure to levels of estrogen metabolites in the sera of 50 pregnant women 25-34 years of age from central Taiwan.

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Although polychlorinated biphenyls (PCBs) have been shown to accumulate in the adrenal, little is known about the effects of these endocrine disruptors on adrenal steroidogenesis. Our previous studies showed that high concentrations of PCB126 stimulated CYP11B1 and CYP11B2 mRNA expression and consequently raised cortisol and aldosterone synthesis in the human adrenocortical H295R cells, respectively. In this study, we further investigated the mechanism underlying the PCB126-induced steroidogenic alterations.

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Epidemiological studies have demonstrated a high association of inorganic arsenic exposure with vascular diseases. Recent research has also linked this vascular damage to impairment of endothelial nitric oxide synthase (eNOS) function by arsenic exposure. However, the role of eNOS in regulating the arsenite-induced vascular dysfunction still remains to be clarified.

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