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Di(2‐ethylhexyl)phthalate (DEHP) has been considered as an estrogen receptor alpha (ERα) agonist due to its ability to interact with ERα and promote the cell proliferation of ERα‐positive breast cancer cells. The impact of DEHP on the chemical therapy in breast cancer is little known. Two breast cancer cell lines, MCF‐7 (ERα‐dependent) and MDA‐MB‐231 (ERα‐independent) were examined. We found that DEHP impaired the effectiveness of camptothecin (CPT) and alleviated the CPT‐induced formation of reactive oxygen species in ERα‐positive MCF‐7 cells, but not in ERα‐negative MDA‐MB‐231 cells. DEHP also significantly protected MCF‐7 cells against the genotoxicity of CPT. Genome‐wide DNA methylation profiling revealed that after 48 hours of exposure to 100 μM DEHP, MCF‐7 cells exhibited a significant change in their DNA methylation pattern, including hypermethylation of 700 genes and hypomethylation of 221 genes. The impaired therapeutic response to CPT in DEHP‐exposed MCF‐7 cells is probably mediated by epigenetic changes, especially through Wnt/β‐catenin signaling. A zebrafish xenograft model confirmed the disruptive effect of DEHP on CPT‐induced anti‐growth of MCF‐7 cells. In summary, DEHP exposure induces acquired CPT‐resistance in breast cancer cells and epigenetic changes associated with Wnt/β‐catenin signaling activation are probably depending on an ER‐positive status. [ABSTRACT FROM AUTHOR]

Background and Aim Hepatitis B virus (HBV) may reactivate when treating chronic hepatitis C (CHC) with direct acting antivirals (DAA). We aim to investigate the risk of HBV reactivation during DAA therapy. Methods Chronic hepatitis C patients receiving pan-oral DAA therapy from December 2013 to August 2016 were evaluated. Fifty-seven patients that had a past HBV infection (negative hepatitis B surface antigen [HBsAg] and positive hepatitis B core antibody) and seven patients that had a current HBV infection (positive HBsAg) were enrolled. Serum HBV and hepatitis C virus (HCV) markers were regularly measured. The endpoints were the HCV sustained virological response (SVR) and the HBV virological/clinical reactivation. Results The overall SVR12 rate was 96.9%, and two patients, one with positive HBsAg, had a relapse of HCV. No episodes of HBV virological reactivation were observed among the patients with a past HBV infection. For the seven patients with a current HBV infection, HBV virological reactivation was found in four (57.1%) of the seven patients. Clinical reactivation of HBV was observed in one patient with pretreatment detectable HBV DNA and recovered after entecavir administration. For the other three patients with HBV virological reactivation, the reappearance of low level HBV DNA without clinical reactivation was observed. HBsAg levels demonstrated only small fluctuations in all the patients. Conclusions There was a minimal impact of hepatitis B core antibody seropositivity on HCV efficacy and safety. For CHC patients with current HBV infection, the risk of HBV reactivation was present, and monitoring the HBV DNA level during therapy is warranted. [ABSTRACT FROM AUTHOR]

Tumor micro-environment is a critical factor in the development of cancer. The aim of this study was to investigate the inflammatory cytokines secreted by tumor-associated dendritic cells (TADCs) that contribute to enhanced migration, invasion, and epithelial-to-mesenchymal transition (EMT) in colon cancer. The administration of recombinant human chemokine (C-C motif) ligand 5 (CCL5), which is largely expressed by colon cancer surrounding TADCs, mimicked the stimulation of TADC-conditioned medium on migration, invasion, and EMT in colon cancer cells. Blocking CCL5 by neutralizing antibodies or siRNA transfection diminished the promotion of cancer progression by TADCs. Tumor-infiltrating CD11c+ DCs in human colon cancer specimens were shown to produce CCL5. The stimulation of colon cancer progression by TADC-derived CCL5 was associated with the up-regulation of non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT-1), which subsequently increased the expression of Snail. Blocking MALAT-1 significantly decreased the TADC-conditioned medium and CCL5-mediated migration and invasion by decreasing the enhancement of Snail, suggesting that the MALAT-1/Snail pathway plays a critical role in TADC-mediated cancer progression. In conclusion, the inhibition of CCL5 or CCL5-related signaling may be an attractive therapeutic target in colon cancer patients. J. Cell. Physiol. 230: 1883-1894, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The interaction between cancer cells and their microenvironment is a paradoxical cycle that exacerbates cancer progression and results in metastasis. Our study investigated the mechanism underlying the synergistic enhancement of release of soluble factors from tumor-associated dendritic cells and its effect on cancer development. The combination of HB-EGF (heparin-binding EGF-like growth factor) and CXCL5 (CXCL5/epithelial neutrophil-activating peptide-78) produced a strong synergistic effect on cancer proliferation, epithelial-mesenchymal transition, migration and invasion. CXCL5 not only potentiated the classical EGFR pathway and the AKT and ERK/RSK1/2 signaling pathways but also increased the phosphorylation of heat shock protein 27 (HSP27), which was slightly increased in A549 cells treated with either HB-EGF or CXCL5 only. Phosphorylated HSP27 stabilized sustained AKT activity by direct interaction, leading to enhanced tumor spheroid formation. Knockdown of HSP27 by shRNA decreased HB-EGF plus CXCL5-mediated tumor spheroid formation in a three-dimensional culture system, suggesting that AKT/HSP27 was required for HB-EGF/CXCL5-mediated cancer progression. Inhibiting RSK also reduces the modulation of c-Fos phosphorylation, Snail upregulation and cell migration by HB-EGF plus CXCL5, suggesting a synergistic effect of ERK/RSK and HB-EGF plus CXCL5 on cell migration. In mice, CXCL5 antibody synergistically enhances the efficiency of the tyrosine kinase inhibitor, gefitinib, without increasing its toxicity. These results provide evidence that elucidates potential cross-points between extracellular signals affecting lung cancer progression. Targeting CXCL5 may provide therapeutic benefits for lung cancer chemotherapy or immunotherapy. [ABSTRACT FROM AUTHOR]

Features of airway remodelling have been described using tissue obtained from fatal cases of asthma and bronchial biopsies from mildly, moderately and severely asthmatic patients. Epithelial detachment and smooth muscle mass enhancement are common features of asthmatic bronchial tissue. This study is the first to investigate the inhibitory effect of nonylphenol (NP) on human bronchial epithelial cell lines BEAS-2B and HBE135-E6E7 (HBE). The results show that NP inhibits bronchial epithelial proliferation via the Fas/Fas ligand apoptotic system. We also treated BEAS-2B and HBE with NP and harvested the condition medium (CM), which was then added to bronchial smooth muscle cells (BSMC). Cultures of BSMC with NP-BEAS-2B-CM and NP-HBE-CM increased BSMC proliferation and migration. Exposure of BEAS-2B and HBE to NP caused epithelial cells to produce inflammatory cytokines IL-6 and IL-8, which subsequently induced BSMC proliferation and migration. Depleting both IL-6 and IL-8 completely reversed the effect of NP-BEAS-2B-CM- and NP-HBE-CM-mediated BSMC proliferation and migration, suggesting that this effect is a synergistic influence of IL-6 and IL-8. This study is the first to demonstrate that NP not only induces bronchial epithelial apoptosis via the Fas-mediated pathway but also stimulates the bronchial epithelium to secrete IL-6 and IL-8, which cause bronchial smooth muscle proliferation and migration - major features in asthma remodelling. [ABSTRACT FROM AUTHOR]

Prostate cancers that are resistant to hormone therapy are more invasive and have greater ability to spread to other organs than androgen-dependent prostate cancers. Furthermore, this type of prostate cancer is also highly resistant to current forms of chemotherapy. This study analyzed CXCL5/ENA78, which is highly expressed in androgen-independent prostate cancers, and is responsible for cell migration and epithelial-to-mesenchymal transition in two androgen-independent prostate cancer cell lines. Inducement of PC-3 and DU145 cancer progression by CXCL5/ENA78 is associated with increased Raf/MEK/ERK activation, and the upregulation of early growth response-1 (Egr-1) and Snail. Blockade of Egr-1 decreased Snail upregulation and cell migration, indicating that Egr-1 is required in CXCL5/ENA78-mediated Snail enhancement and cell migration. In addition, Egr-1 siRNA also decreased the effect of CXCL5/ENA78 on p27 inhibition, Cdk4 induction and cell proliferation, suggesting Egr-1 is also involved in CXCL5/ENA78-mediated cell growth. Moreover, blocking ERK1/2 by siRNA suppressed CXCL5/ENA78-induced Egr-1 enhancement, cell migration, and proliferation. Our study suggests that inhibition of CXCL5/ENA78-mediated ERK/Egr-1/Snail signaling is an attractive therapeutic target for androgen-independent prostate cancer. J. Cell. Physiol. 226: 1224-1231, 2011. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

1. Norsolorinic acid, isolated from Aspergillus nidulans, has been shown to have antiproliferative activity in T24 human bladder cancer cells by arresting the cell cycle at the G0/G1 phase and inducing apoptosis. The aim of the present study was to investigate the antiproliferative activity of norsolorinic acid in T24 human bladder cancer cells. 2. The effects of norsolorinic acid (1, 5, 10 and 20 µmol/L) on the proliferation of T24 cells and on the distribution of cells within different phases of the cell cycle were investigated indirectly using an XTT assay and a flow cytometer, respectively. Factors affecting the cell cycle and apoptosis, including p53, p21, Fas receptor, Fas ligand (FasL) and caspase 8 activity, were examined using ELISA. 3. The results showed that norsolorinic acid inhibited proliferation of T24 cells in a dose-dependent manner, with an IC50 of 10.5 µmol/L. The effect involved the induction of cell cycle arrest at the G0/G1 phase and apoptosis. 4. These results demonstrate that G0/G1 phase arrest is due to increased expression of p21 in cells treated with norsolorinic acid (10 and 20 µmol/L) for 24 h. Moreover, enhanced Fas and membrane-bound Fas ligand (mFasL) may be responsible for the apoptotic effect of norsolorinic acid. Thus, the present study reports, for the first time, that induction of p21 and the Fas/mFas ligand apoptotic system may participate in the antiproliferative action of norsolorinic acid in T24 human bladder cancer cells. [ABSTRACT FROM AUTHOR]

Background and Aim: Huang-lian-jie-du-tang (HLJDT; Japanese name, oren-gedoku-to) is a traditional Chinese medicine prescription known to possess anti-inflammatory activity. Our study reports here for the first time the anticancer effect of HLJDT in two human liver cancer cell lines, Hep G2 and PLC/PRF/5. Methods: Inhibition of cell proliferation by HLJDT was measured by sodium 3′-(1-(phenylamino-carbonyl)-3,4-tetrazolium)-bis(4-methoxy-6-nitro) benzene-sulfonic acid hydrate (XTT) assay. Clonogenic assay was used to elucidate the possible differences in long-term effects of HLJDT on human liver cancer cells. Cell cycle distribution was determined by flow cytometry. Apoptosis was detected using electrophoresis and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick endlabeling (TUNEL) assay. Protein expressions were determined by immunoblot assay. The activity of nuclear factor–kappa B (NF-κB) was determined by Trans-AM ELISA kit. In vivo tumor activity was assessed by xenograft study. Results: HLJDT significantly increased the expression of inactivated phospho-Cdc2 and phospho-Cdc25C, and decreased the levels of cyclin A, cyclin B1, Cdc2, and Cdc25C, thereby contributing to cell-cycle arrest. HLJDT increased the expression of Bax and Bak, but decreased the level of Bcl-2 and Bcl-XL, and subsequently triggered the mitochondrial apoptotic pathway. In addition, HLJDT also inhibited cell-survival signaling by enhancing the amount of IκBα in the cytoplasm, reducing the level and activity of NF-κB in the nucleus, and subsequently attenuating the expression of Bcl-XL in Hep G2 and PLC/PRF/5 cells. The inhibitory effect mediated by HLJDT on cell growth was also demonstrated in a nude mouse model, in which the liver cancer cells induced tumor xenograft shrank considerably following treatment with HLJDT. Conclusions: Taken together, these results suggest a potential anticancer effect of HLJDT against human liver cancer cells. [ABSTRACT FROM AUTHOR]

1. Gossypol has wide antineoplastic effectsin vitro, but its effects on human lung cancer have not been explored.2. To evaluate the activity of gossypol against alveolar cell lung cancer and to provide information on the mechanism of action, we examined the effects of gossypol on the proliferation of A549 cells indirectly using an XTT assay and on the distribution of cells within the phases of the cell cycle using flow cytometry. We also examined several factors that may affect apoptosis, including p53, p21/WAF1, Fas receptor, Fas ligand (FasL) and caspase 8 activity.3. The results showed that gossypol inhibited proliferation of A549 cells at a concentration of 0.5 µmol/L after 12 h treatment. The effect was both dose- and time-dependent by the induction of apoptosis without the effect of p53 and p21/WAF1.4. Upregulation of Fas/FasL, in association with the activation of downstream caspase 8 activity, was observed following treatment with gossypol. The Fas/FasL pathway accounted for 75% of gossypol-mediated apoptosis.5. We suggest that the Fas/FasL apoptotic system is the major pathway for gossypol-mediated apoptosis of A549 cells.6. Gossypol had no effect on the distribution of A549 cells within the phases of the cell cycle.7. In conclusion, gossypol inhibited A549 cells mainly by induction of the Fas/FasL apoptotic pathway, but not the p53 and p21/WAF1 pathway. [ABSTRACT FROM AUTHOR]

1. Norsolorinic acid, isolated from Aspergillus nidulans, has been shown to have antiproliferative activity in T24 human bladder cancer cells by arresting the cell cycle at the G(0)/G(1) phase and inducing apoptosis. The aim of the present study was to investigate the antiproliferative activity of norsolorinic acid in T24 human bladder cancer cells. 2. The effects of norsolorinic acid (1, 5, 10 and 20 micromol/L) on the proliferation of T24 cells and on the distribution of cells within different phases of the cell cycle were investigated indirectly using an XTT assay and a flow cytometer, respectively. Factors affecting the cell cycle and apoptosis, including p53, p21, Fas receptor, Fas ligand (FasL) and caspase 8 activity, were examined using ELISA. 3. The results showed that norsolorinic acid inhibited proliferation of T24 cells in a dose-dependent manner, with an IC(50) of 10.5 micromol/L. The effect involved the induction of cell cycle arrest at the G(0)/G(1) phase and apoptosis. 4. These results demonstrate that G(0)/G(1) phase arrest is due to increased expression of p21 in cells treated with norsolorinic acid (10 and 20 micromol/L) for 24 h. Moreover, enhanced Fas and membrane-bound Fas ligand (mFasL) may be responsible for the apoptotic effect of norsolorinic acid. Thus, the present study reports, for the first time, that induction of p21 and the Fas/mFas ligand apoptotic system may participate in the antiproliferative action of norsolorinic acid in T24 human bladder cancer cells.

1. Isoliquiritigenin (ISL) is a natural pigment with the simple chalcone structure 4,2',4'-trihydroxychalcone. In the present study, we report, for the first time, ISL-induced inhibition of the proliferation of the human non-small cell lung cancer A549 cell line. 2. The results showed that ISL not only inhibited A549 cell proliferation, but also induced apoptosis and blocked cell cycle progression in the G1 phase. An ELISA assay demonstrated that ISL significantly increased the expression of p53 and p21/WAF1 protein, which caused cell cycle arrest. 3. An enhancement in Fas and its two ligands, namely membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), may be responsible for the apoptotic effect induced by ISL. 4. Taken together, the results indicate that the p53 and Fas/FasL apoptotic system may participate in the antiproliferative activity of ISL in A549 cells.