Exploring the residential exposome: Determination of hazardous flame retardants in air filter dust from HVAC systems.

Dust is a sink for flame retardants, which are added to a myriad of consumer products in residential spaces. Organophosphate esters (OPEs) and brominated flame retardants (BFRs) are two classes of flame retardants that are frequently used in consumer products and consequently found in dust. In this present work, a novel solvent-limited microextraction technique, which we detailed in a companion study, was applied for the determination of four OPEs and two BFRs with limits of quantitation at the ng/g level by gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry from n = 47 air filter dust samples collected from forced air HVAC systems. Levels of the BFRs, including tetrabromobisphenol-A and its derivative tribromobisphenol-A, were found at levels <4 µg/g and not frequently detected. Conversely, all four OPEs were detected in all air filter dust samples. Total OPE load was dominated by tris(2,4-di-tert-butylphenyl) phosphate, T24DtBPP, a novel OPE not widely examined in the literature. Comparison of individual and total OPE concentrations to residential characteristics revealed statistically significant relationships to location of the home and dominant flooring type. Overall, this study motivates future work in examining the whole house exposome using air filter dust as a passive sampling regime with more examination of T24DtBPP loads within other indoor spaces.

Vitamin D increases the efficacy of cisplatin on bladder cancer cell lines.

BACKGROUND: 1,25(OH)2D3(Calcitriol), which is a broad regulatory molecule, plays a role in changing the efficacy of chemotherapeutic drugs. Cisplatin is one of a current standard chemotherapy regimen for bladder cancer. Increasing the effectiveness of the treatment and reducing the side effects to chemotherapeutics are of great importance in bladder cancer. We aimed to investigate the effect of the combination of cisplatin and calcitriol in order to create a possible advantage in treatment of bladder cancer. METHODS: T24, ECV-304 and HUVEC cell lines were treated with calcitriol and cisplatin individually and in combination. Dose determination and combination treatments of calcitriol and cisplatin were evaluated using the MTT assay for cytotoxicity analysis on the cells. Annexin V-PI staining method was used for apoptosis determination by flow cytometry. Also the P-gp expression levels were determined by flow cytometry. RESULTS: The combination treatment increased the anti-proliferative efficacy compared to the efficacy in cisplatin alone in T24 cells and reduced the cytotoxicity in the HUVEC healthy cells compared to cisplatin alone. Combination treatment achieved significantly higher apoptosis rate in T24 cells compared with the rates in treatment of cisplatin alone. However apoptosis decreased in HUVEC cell line. P-gp ratios were increased in HUVEC and decreased in T24 cells with combination treatment compared to the numbers in the control cells. The rate of apoptosis and P-gp levels showed no significant change in ECV-304 cells. CONCLUSION: Our study revealed that the combination of calcitriol and cisplatin allows the use of cisplatin at lower doses in T24 bladder cancer cell line.

Effective-by-method for the preparation of folic acid-coated TiO2 nanoparticles with high targeting potential for apoptosis induction against bladder cancer cells (T24).

The research's goal is to create the surfaces of titanium dioxide nanoparticles (TiO2 NPs) in a layer of folic acid (FA) that can effectively target human bladder cancer cells (T24). An efficient method for creating FA-coated TiO2 NPs was used, and many tools have been used to analyze its physicochemical properties. The cytotoxic effects of FA-coated NPs on T24 cells and the mechanisms of apoptosis generation were examined employing a variety of methodologies. The prepared FA-coated TiO2 NPs suspensions with a hydrodynamic diameter around 37 nm and a negative surface charge of -30 mV reduced T24 cell proliferation with stronger IC50 value (21.8 ± 1.9 µg/ml) than TiO2 NPs (47.8 ± 2.5 µg/ml). This toxicity resulted in apoptosis induction (16.63%) that was caused through enhanced reactive oxygen species formation and stopping the cell cycle over G2/M phase. Moreover, FA-TiO2 NPs raised the expression levels of P53, P21, BCL2L4, and cleaved Caspase-3, while decreasing Bcl-2, Cyclin B, and CDK1 in treated cells. Overall, these findings revealed efficient targeting of the FA-TiO2 NPs resulted in increasing cellular internalization caused increased apoptosis in T24 cells. As a result, FA-TiO2 NPs might be a viable treatment for human bladder cancer.

Activation of autophagy triggers mitochondrial loss and changes acetylation profile relevant for mechanotransduction in bladder cancer cells.

Bladder cells are constantly exposed to multiple xenobiotics and bioactive metabolites. In addition to this challenging chemical environment, they are also exposed to shear stress originating from urine and interstitial fluids. Hence, physiological function of bladder cells relies on a high biochemical and biomechanical adaptive competence, which, in turn, is largely supported via autophagy-related mechanisms. As a negative side of this plasticity, bladder cancer cells are known to adapt readily to chemotherapeutic programs. At the molecular level, autophagy was described to support resistance against pharmacological treatments and to contribute to the maintenance of cell structure and metabolic competence. In this study, we enhanced autophagy with rapamycin (1-100 nM) and assessed its effects on the motility of bladder cells, as well as the capability to respond to shear stress. We observed that rapamycin reduced cell migration and the mechanical-induced translocation potential of Krüppel-like transcription factor 2 (KLF2). These effects were accompanied by a rearrangement of cytoskeletal elements and mitochondrial loss. In parallel, intracellular acetylation levels were decreased. Mechanistically, inhibition of the NAD + -dependent deacetylase sirtuin-1 (SIRT1) with nicotinamide (NAM; 0.1-5 mM) restored acetylation levels hampered by rapamycin and cell motility. Taken together, we described the effects of rapamycin on cytoskeletal elements crucial for mechanotransduction and the dependency of these changes on the mitochondrial turnover caused by autophagy activation. Additionally, we could show that targeted metabolic intervention could revert the outcome of autophagy activation, reinforcing the idea that bladder cells can easily adapt to multiple xenobiotics and circumvent in this way the effects of single chemicals.

RNA-seq reveals novel mechanistic targets of Livin in bladder cancer.

BACKGROUND: Bladder cancer is a very common malignancy with a high recurrence rate. The survival of patients with muscle-invasive bladder cancer is poor, and new therapies are needed. Livin has been reported to be upregulated in bladder cancer and influence the proliferation of cancer cells. MATERIALS AND METHODS: The Livin gene in human bladder cancer cell line T24 was knocked out, and the differentially expressed genes were identified by RNA-seq and qPCR. RESULTS: Livin knockdown affects gene expression and has strong negative effects on some cancer-promoting pathways. Furthermore, combined with bladder cancer clinical sample data downloaded from TCGA and GEO, 2 co-up-regulated genes and 58 co-down-regulated genes were identified and validated, which were associated with cancer proliferation and invasion. CONCLUSION: All these results suggest that Livin plays an important role in bladder cancer and could be a potential anticancer target in clinical therapy.

Sakuranin represses the malignant biological behaviors of human bladder cancer cells by triggering autophagy via activating the p53/mTOR pathway.

OBJECTIVE: Sakura extract is a natural flavonoid compound that may have potential anti-tumor effects. The paper focuses on investigating Sakuranin mechanism on bladder cancer (BC) cells. METHODS: BC cells (T24) were treated with different concentrations of Sakuranin, with 48-h IC50 determined. T24 cells were treated with Sakuranin at IC50, followed by assessment of cell proliferative/apoptotic/migrative/invasive activities by CCK-8, EdU and plate clone formation assays/flow cytometry/Transwell/scratch test. MMP-2 (migration and invasion-related protein) protein level was assessed by Western blot. Cell autophagy was evaluated by measuring the protein levels of autophagy markers (LC3-I/LC3-II/p62) through Western blot. The autophagy inhibitor 3-MA was used to validate the role of autophagy in the regulatory mechanism of Sakuranin in T24 cell behaviors. Furthermore, the activation of the p53/mTOR pathway in cells was detected and a combination of Sakuranin and p53 inhibitor Pifithrin-µ was adopted to explore the involvement of this pathway. RESULTS: Sakuranin decreased T24 cell proliferation/EdU positive cell percentage/colony formation number and area/migration/invasion/scratch healing/MMP-2 protein level, and accelerated apoptosis. Sakuranin elevated the LC3-II/I ratio and lowered p62 level in T24 cells. 3-MA partially averted Sakuranin-mediated repression on cell malignant behaviors. Sakuranin upregulated p-p53 and p53 levels, and decreased the p-mTOR/mTOR ratio in T24 cells. The effects of Sakuranin on cell biological behaviors were partly annulled by Pifithrin-µ treatment. CONCLUSION: Sakuranin suppressed T24 cell proliferation/migration/invasion, and enhanced apoptosis by potentiating autophagy through activating the p53/mTOR pathway. This study provided a theoretical basis for Sakuranin as a potential drug for clinical treatment of BC.

Apoptotic and anti-angiogenic effects of propolis against human bladder cancer: molecular docking and in vitro screening.

INTRODUCTION: Bladder cancer is still of unknown initiation and progression, it is difficult to treat the patient once bladder cancer have a distant metastasis. MATERIALS AND METHODS: In the present study, propolis extract was evaluated against bladder cancer cells (T24). Two independent pathways were investigated, apoptosis and angiogenesis, Bax, Bcl-2, P53, and caspase-3 for apoptosis, vascular endothelial growth factor receptor and protein kinase A as angiogenesis potential targets. OBJECTIVES: Molecular docking studies will be conducted for the major known constituents of Egyptian propolis into apoptotic and angiogenic protein targets, to give better insights to the possible binding mode and interactions and investigate the ability of propolis constituents to target both apoptotic and angiogenic pathways. RESULTS: Propolis showed anti-proliferative activity against T24 cancer cell line, the IC50 value was 6.36 µg/ml. Also significant effects of propolis on Bax, Bcl-2, P53, and caspase-3 were observed. DISCUSSION: These obtained results proved the ability of propolis to induce cell death. Also it has revealed noticeable effects on protein kinase A and vascular endothelial growth factor receptor. CONCLUSION: The obtained results can encourage us to say that propolis extract can induce a programmed cell death in human bladder cancer cells, and also affect angiogenesis.

Metformin exerts an antitumor effect by inhibiting bladder cancer cell migration and growth, and promoting apoptosis through the PI3K/AKT/mTOR pathway.

BACKGROUND: To observe and explore the effect of metformin on the migration and proliferation of bladder cancer T24 and 5637 cells in vitro. METHODS: Bladder cancer T24 and 5637 cell lines were cultured in vitro, and were divided into group A (blank control group) and group B (metformin group: 5, 10, 15, and 20 mmol/L); both groups were plated on 6-well plates at the same time. Culture in 24-well plates was used for wound healing assays and in 96-well plates for Transwell migration and invasion, and Cell Counting Kit-8 proliferation experiments. We observed and detected the cell migration and proliferation ability of each group at 48 h, and calculated the cell migration area and survival rate. Flow cytometry was used to detect cell apoptosis in the groups. The apoptosis-related proteins, cleaved-caspase 3, cleaved-PARP, and the PI3K/AKT/mTOR signaling pathway member proteins PI3K, phosphorylated (p)-PI3K, AKT, p-AKT, mTOR, and p-mTOR were detected using western blotting. RESULTS: After 48 h of treatment with different concentrations of metformin, the cell migration and proliferation capabilities were significantly lower than those in the blank control group. The proliferation and migration abilities of T24 and 5637 cells decreased in a metformin concentration-dependent manner (P < 0.05). The apoptosis rate under different concentrations of metformin, as detected by flow cytometry, showed a significantly higher rate in the metformin group than in the control group (P < 0.05). Compared with that in the control group, the level of cleaved-caspase 3 and cleaved-PARP protein in the metformin group was increased in each treatment group, and the levels of p-mTOR, p-AKT, and p-PI3K decreased significantly compared with those in the control group (P < 0.05). CONCLUSION: Metformin inhibited bladder cancer T24 and 5637 cell migration and proliferation, and induced their apoptosis. The mechanism might involve inhibition of the activation of the PI3K/AKT/mTOR signaling pathway.

Folic Acid-Doxorubicin-Double-Functionalized-Lipid-Core Nanocapsules: Synthesis, Chemical Structure Elucidation, and Cytotoxicity Evaluation on Ovarian (OVCAR-3) and Bladder (T24) Cancer Cell Lines.

PURPOSE: Folic acid-doxorubicin-double-functionalized-lipid-core nanocapsules (LNC-CS-L-Zn+2-DOX-FA) were prepared, characterized, and evaluated in vitro against ovarian and bladder cancer cell lines (OVCAR-3 and T24). METHODS: LNC-CS-L-Zn+2-DOX-FA was prepared by self-assembly and interfacial reactions, and characterized using liquid chromatography, particle sizing, transmission electron microscopy, and infrared spectroscopy. Cell viability and cellular uptake were studied using MTT assay and confocal microscopy. RESULTS: The presence of lecithin allows the formation of nanocapsules with a lower tendency of agglomeration, narrower size distributions, and smaller diameters due to an increase in hydrogen bonds at the surface. LNC-L-CS-Zn+2-DOX-FA, containing 98.00 ± 2.34 µg mL-1 of DOX and 105.00 ± 2.05 µg mL-1 of FA, had a mean diameter of 123 ± 4 nm and zeta potential of +12.0 ± 1.3 mV. After treatment with LNC-L-CS-Zn+2-DOX-FA (15 µmol L-1 of DOX), T24 cells had inhibition rates above 80% (24 h) and 90% (48 h), whereas OVCAR-3 cells showed inhibition rates of 68% (24 h) and 93% (48 h), showing higher cytotoxicity than DOX.HCl. The fluorescent-labeled formulation showed a higher capacity of internalization in OVCAR-3 compared to T24 cancer cells. CONCLUSION: Lecithin favored the increase of hydrogen bonds at the surface, leading to a lower tendency of agglomeration for nanocapsules. LNC-CS-L-Zn+2-DOX-FA is a promising therapeutic agent against tumor-overexpressing folate receptors.

Antibacterial Therapy by Ag+ Ions Complexed with Titan Yellow/Congo Red and Albumin during Anticancer Therapy of Urinary Bladder Cancer.

According to the World Health Organization report, the increasing antibiotic resistance of microorganisms is one of the biggest global health problems. The percentage of bacterial strains showing multidrug resistance (MDR) to commonly used antibiotics is growing rapidly. Therefore, the search for alternative solutions to antibiotic therapy has become critical to combat this phenomenon. It is especially important as frequent and recurring infections can cause cancer. One example of this phenomenon is urinary tract infections that can contribute to the development of human urinary bladder carcinoma. This tumor is one of the most common malignant neoplasms in humans. It occurs almost three times more often in men than in women, and in terms of the number of cases, it is the fifth malignant neoplasm after prostate, lung, colon, and stomach cancer. The risk of developing the disease increases with age. Despite the improvement of its treatment methods, the current outcome in the advanced stages of this tumor is not satisfactory. Hence, there is an urgent need to introduce innovative solutions that will prove effective even in the advanced stage of the disease. In our study, a nanosystem based on ionic silver (Ag+) bound to a carrier-Titan yellow (TY) was analyzed. The possibility of binding the thus formed TY-Ag system to Congo red (CR) and albumin (BSA) was determined. TY-Ag binding to CR provides for better nanosystem solubility and enables its targeted intracellular transport and binding to immune complexes. The binding of TY-Ag or CR-TY-Ag to albumin also protects the system against the uncontrolled release of silver ions. It will also allow the delivery of silver in a targeted manner directly to the desired site in the case of intravenous administration of such a system. In this study, the MIC (Minimum Inhibitory Concentration) and MBC (Minimum Bactericidal Concentration) values of the TY-Ag or BSA-TY-Ag systems were determined in two reference strains (Escherichia coli and Staphylococcus aureus). The paper presents nanosystems with a size of about 40-50 nm, with an intense antibacterial effect obtained at concentrations of 0.019 mM. We have also discovered that TY-Ag free or complexed with BSA (with a minimal Ag+ dose of 15-20 µM) inhibited cancer cells proliferation. TY-Ag complex diminished migration and effectively inhibited the T24 cell viability and induced apoptosis. On the basis of the obtained results, it has been shown that the presented systems may have anti-inflammatory and antitumor properties at the same time. TY-Ag or BSA-TY-Ag are new potential drugs and may become in future important therapeutic compounds in human urinary bladder carcinoma treatment and/or potent antimicrobial factors as an alternative to antibiotics.

PapG subtype-specific binding characteristics of Escherichia coli towards globo-series glycosphingolipids of human kidney and bladder uroepithelial cells.

Uropathogenic Escherichia coli (UPEC) are the primary cause of urinary tract infections (UTIs) in humans. P-fimbriae are key players for bacterial adherence to the uroepithelium through the Galα1-4Gal-binding PapG adhesin. The three identified classes I, II and III of PapG are supposed to adhere differently to host cell glycosphingolipids (GSLs) of the uroepithelial tract harboring a distal or internal Galα1-4Gal sequence. In this study, GSL binding characteristics were obtained in a nonradioactive adhesion assay using biotinylated E. coli UTI and urine isolates combined with enzyme-linked NeutrAvidin for detection. Initial experiments with reference globotriaosylceramide (Gb3Cer, Galα1-4Galß1-4Glcß1-1Cer), globotetraosylceramide (Gb4Cer, GalNAcß1-3Galα1-4Galß1-4Glcß1-1Cer) and Forssman GSL (GalNAcα1-3GalNAcß1-3Galα1-4Galß1-4Glcß1-1Cer) revealed balanced adhesion toward the three GSLs for PapG I-mediated attachment. In contrast, E. coli carrying PapG II or PapG III increasingly adhered to growing oligosaccharide chain lengths of Gb3Cer, Gb4Cer and Forssman GSL. Binding studies with GSLs from human A498 kidney and human T24 bladder epithelial cells, both being negative for the Forssman GSL, revealed the less abundant Gb4Cer vs. Gb3Cer as the prevalent receptor in A498 cells of E. coli expressing PapG II or PapG III. On the other hand, T24 cells exhibited a higher relative content of Gb4Cer vs. Gb3Cer alongside dominant binding of PapG II- or PapG III-harboring E. coli toward Gb4Cer and vastly lowered attachment to minor Gb3Cer. Further studies on PapG-mediated interaction with cell surface-exposed GSLs will improve our knowledge on the molecular mechanisms of P-fimbriae-mediated adhesion and may contribute to the development of antiadhesion therapeutics to combat UTIs.

ALDOLASE A regulates invasion of bladder cancer cells via E-cadherin-EGFR signaling.

Glycolysis and glycogenesis are known to be tightly associated with cancer cell migration. However, their roles in bladder cancer have not been reported. In this study, ALDOLASE A (ALDOA) was identified in a coexpression network generated using glycolysis- and glycogenesis-related genes in Kyoto Encyclopedia of Genes and Genomes. ALDOA was located in the central region in the network, and the cancer genome atlas (TCGA) data suggest that ALDOA expression levels are associated with viability in patients with cancer at the middle and late stages. Bladder cancer cell lines, T24 and RT4, were used to knockdown (sh) or overexpress (OE) ALODA to analyze its role. The sh-ALDOA reduced cell viability, colony formation rate, and invasion cell number; while OE had an opposite effect compared with sh-ALDOA. Further, the sh-ALDOA expression induced E-cadherin level while reduced N-cadherin and vimentin levels. The OE cells reduced E-cadherin and induced N-cadherin and vimentin levels. In addition, epidermal growth factor receptor (EGFR), mitogen-activated protein kinase (MAPK), and AKT serine/threonine kinase (AKT) phosphorylation levels are all reduced in sh-ALODA while activated in OE cells compared with the control group. But either sh-ALODA or OE did not change total protein levels of EGFR, MAPK, and AKT. To further analyze E-cadherin function in ALDOA regulation on bladder cancer cells, sh-ALDOA and sh-E-cadherin were cotransfected in T24 and RT4 cells. The results indicated that sh-ALDOA and sh-E-cadherin expressions eliminated sh-ALDOA function, resulting similar cell viability, colony formation rate, and invasion cell number with control group. Also, sh-ALDOA and shE-cadherin expressions increased EGFR, MAPK, and AKT phosphorylation levels; and the levels were similar to the control group. But, sh-ALDOA and sh-E-cadherin expressions did not change N-cadherin and vimentin levels, which maintain similar levels with sh-ALDOA-expressing cells. Taken together, these results suggest that ALDOA might play an important function in bladder cancer and its action may be though E-cadherin-EGFR signaling.

Brazilin induces T24 cell death through c-Fos and GADD45ß independently regulated genes and pathways.

Purified Brazilin from Sappan wood extract has been reported with significant antitumor effect, especially on human T24 cells and bladder cancer mouse models. Brazilin can significantly induce expression of c-Fos and GADD45ß and transfection expression of c-Fos and GADD45ß in T24 cells can induce significant cell morphology changes, reduced viability and cell death, while transfection of siRNA-c-Fos and siRNA-GADD45ß can reverse the induced cell death. Co-transfection of both c-Fos and GADD45ß into T24 cells resulted in a significantly additive effect when compared to single transfection with only c-Fos or GADD45ß. Meanwhile, transfection of interfering siRNA-c-Fos or siRNA-GADD45ß can partially rescue the cell viability and siRNA co-transfection showed increased rescue rate. The transfection expression and interference with pcDNA3.1-c-Fos/siRNA-c-Fos or pcDNA3.1-GADD45ß/siRNA-GADD45ß did not affect each other's expression. Moreover, analysis of c-Fos and GADD45ß regulated genes and signal pathways showed that no common regulated genes or pathways were present. All the results indicated that c-Fos and GADD45ß mediate independent Brazilin-inducible genes and pathways. © 2018 IUBMB Life, 70(11):1101-1110, 2018.

Hazard assessment of three haloacetic acids, as byproducts of water disinfection, in human urothelial cells.

Disinfection by-products (DBPs) are compounds produced in the raw water disinfection processes. Although increased cancer incidence has been associated with exposure to this complex mixture, the carcinogenic potential of individual DBPs remains not well known; thus, further studies are required. Haloacetic acids (HAAs) constitute an important group among DBPs. In this study, we have assessed the in vitro carcinogenic potential of three HAAs namely chloro-, bromo-, and iodoacetic acids. Using a long-term (8 weeks) and sub-toxic doses exposure scenario, different in vitro transformation markers were evaluated using a human urothelial cell line (T24). Our results indicate that long-term exposure to low doses of HAAs did not reproduce the genotoxic effects observed in acute treatments, where oxidative DNA damage was induced. No changes in the transformation endpoints analyzed were observed, as implied by the absence of significant morphological, cell growth rate and anchorage-independent cell growth pattern modifications. Interestingly, HAA-long-term exposed cells developed resistance to oxidative stress damage, what would explain the observed differences between acute and long-term exposure conditions. Accordingly, data obtained under long-term exposure to sub-toxic doses of HAAs could be more accurate, in terms of risk assessment, than under acute exposure scenarios.

Matrine combined with cisplatin synergistically inhibited urothelial bladder cancer cells via down-regulating VEGF/PI3K/Akt signaling pathway.

BACKGROUND: Cisplatin is one of the first-line drugs for urothelial bladder cancer (UBC) treatment. However, its considerable side effects and the emergence of drug resistance are becoming major limitations for its application. This study aimed to investigate whether matrine and cisplatin could present a synergistic anti-tumor effect on UBC cells. METHODS: Cell viability assay was used to assess the suppressive effect of matrine and cisplatin on the proliferation of the UBC cells. Wound healing assay and transwell assay were applied respectively to determine the migration and invasion ability of the cells. The distribution of cell cycles, the generation of reactive oxygen species (ROS) and the apoptosis rate were detected by flow cytometry (FCM). The expressions of the relative proteins in apoptotic signal pathways and the epithelial-mesenchymal transition (EMT) related genes were surveyed by western blotting. The binding modes of the drugs within the proteins were detected by CDOCKER module in DS 2.5. RESULTS: Both matrine and cisplatin could inhibit the growth of the UBC cells in a time- and dose-dependent manner. When matrine combined with cisplatin at the ratio of 2000:1, they presented a synergistic inhibitory effect on the UBC cells. The combinative treatment could impair cell migration and invasion ability, arrest cell cycle in the G1 and S phases, increase the level of ROS, and induce apoptosis in EJ and T24 cells in a synergistic way. In all the treated groups, the expressions of E-cadherin, ß-catenin, Bax, and Cleaved Caspase-3 were up-regulated, while the expressions of Fibronectin, Vimentin, Bcl-2, Caspase-3, p-Akt, p-PI3K, VEGFR2, and VEGF proteins were down-regulated, and among them, the combination of matrine and cisplatin showed the most significant difference. Molecular docking algorithms predicted that matrine and cisplatin could be docked into the same active sites and interact with different residues within the tested proteins. CONCLUSIONS: Our results suggested that the combination of matrine and cisplatin could synergistically inhibit the UBC cells' proliferation through down-regulating VEGF/PI3K/Akt signaling pathway, indicating that matrine may serve as a new option in the combinative therapy in the treatment of UBC.

Reprogramming bladder cancer cells for studying cancer initiation and progression.

The induced pluripotent stem cell (iPSC) technology is the forced expression of specific transcription factors in somatic cells resulting in transformation into self-renewing, pluripotent cells which possess the ability to differentiate into any type of cells in the human body. While malignant cells could also be reprogrammed into iPSC-like cells with lower efficiency due to the genetic and epigenetic barriers in cancer cells, only a limited number of cancer cell types could be successfully reprogrammed until today. In the present study, we aimed at reprogramming two bladder cancer cell lines HTB-9 and T24 using a non-integrating Sendai virus (SeV) system. We have generated six sub-clones using distinct combinations of four factors-OCT4, SOX2, KLF4 and c-MYC-in two bladder cancer cell lines. Only a single sub-clone, T24 transduced with 4Fs, gave rise to iPSC-like cells. Bladder cancer cell-derived T24 4F cells represent unique features of pluripotent cells such as epithelial-like morphology, colony-forming ability, expression of pluripotency-associated markers and bearing the ability to differentiate in vitro. This is the first study focusing on the reprogramming susceptibility of two different bladder cancer cell lines to nuclear reprogramming. Further molecular characterisation of T24 4F cells could provide a better insight for biomarker research in bladder carcinogenesis and could offer a valuable tool for the development of novel therapeutic approaches in bladder carcinoma.

Inhibition of epithelial-mesenchymal transition in bladder cancer cells via modulation of mTOR signalling.

Mounting evidence suggests that signalling cross-talk plays a significant role in the regulation of epithelial-mesenchymal transition (EMT) in cancer cells. However, the complex network regulating the EMT in different cancer types has not been fully described yet which affects the development of novel therapeutic strategies. In the present study, we investigated the signalling pathways involved in EMT of bladder cancer cells and demonstrated the effects of two novel agents in the regulation of EMT. Myrtucommulone-A (MC-A) and thymoquinone (TQ) have been shown to possess anti-cancer properties. However, their targets in the regulation of cancer cell behavior are not well defined. Here, we defined the effects of two putative anti-cancer agents on bladder cancer cell migration and their possible intracellular targets in the regulation of EMT. Our results suggest that MC-A or TQ treatment affected N-cadherin, Snail, Slug, and ß-catenin expressions and effectively attenuated mTOR activity. The downstream components in mTOR signalling were also affected. MC-A treatment resulted in the concomitant inhibition of extracellular matrix-regulated protein kinases 1 and 2 (ERK 1/2), p38 mitogen-activated protein kinase (MAPK) and Src activity. On the other hand, TQ treatment increased Src activity while exerting no effect on ERK 1/2 or p38 MAPK activity. Given the stronger inhibition of EMT-related markers in MC-A-treated samples, we concluded that this effect might be due to collective inhibition of multiple signalling pathways which result in a decrease in their cross-talk in bladder cancer cells. Overall, the data in this study proposes novel action mechanisms for MC-A or TQ in bladder cancer cells and highlights the potential use of these active compounds in the regulation of EMT.

Autophagy inhibition suppresses the tumorigenic potential of cancer stem cell enriched side population in bladder cancer.

The mechanisms that underlie tumor formation and progression have not been elucidated in detail in cancer biology. Recently, the identification of a tumor cell subset defined as cancer stem cells (CSCs), which is enriched for tumor initiating capacity, has engendered new perspectives towards selective targeting of tumors. In this study, we isolated the side population (SP) cells which share characteristics of CSCs from bladder cancer cell lines, T24 and UM-UC-3 by fluorescence activated cell sorting. The cells were cultured in serum free medium and expression profile of stem cell like markers (SOX-2, NANOG, KLF-4 and OCT-4), drug resistant genes (ABCG2 and MDR1) and spheroid forming capability were examined in SP, non-side population (NSP) and bulk T24 and UM-UC-3 cells. We observed that SP cells possessed a higher mRNA expression of SOX-2, NANOG, KLF-4, OCT-4, ABCG2, and MDR1 as well as a higher spheroid forming ability as compared to other bulk cells or NSP cells. The SP cells had low ROS levels and high GSH/GSSG ratio which may contribute to radio-resistance. The SP cells also showed substantial resistance to gemcitabine, mitomycin and cisplatin compared with the NSP counterpart. A high autophagic flux was observed in the SP cells. Both pharmacological and siRNA mediated inhibition of autophagy potentiated the chemotherapeutic effects of gemcitabine, mitomycin and cisplatin in these cells. We concluded that the ABCG2 expressing SP cells show autophagy associated cell survival and may be a potent target for developing more effective treatment in bladder carcinoma to enhance patient survival.

c-Fos is involved in inhibition of human bladder carcinoma T24 cells by brazilin.

Crude brazilin extract from Sappan wood has demonstrated strong anti tumor activity in the mouse model of human bladder carcinoma and clinical trial for intravesical therapy. Purified brazilin was confirmed the most active molecule in inhibition of bladder carcinoma T24 cells. Brazilin decreased proliferation and viability of T24 cells in a dose- and time-dependent manner, with a calculated LC50 of 32 µg/mL. More than 1,000 of genes were found upregulated and down regulated by brazilin treatment in digital gene expression profiling. Gene ontology analysis indicated that stress response, apoptosis, and cell cycle regulatory pathways were highly enriched. Among the regulated genes, c-Fos was the most and specifically upregulated. Overexpression of c-Fos in T24 cells resulted in tumor cell specific changes in cell morphology and viability. Over expression of stress-responsive gene, HSP70, and other highly upregulated genes did not have any effect on cell growth. Brazilin may inhibit T24 cell growth and trigger cell death through a c-Fos-mediated and tumor cell specific signaling pathway. Further studies of its down stream mediators may help to identify better tumor cell type specific drug targets.

Anti-Adhesive Activity of Cranberry Phenolic Compounds and Their Microbial-Derived Metabolites against Uropathogenic Escherichia coli in Bladder Epithelial Cell Cultures.

Cranberry consumption has shown prophylactic effects against urinary tract infections (UTI), although the mechanisms involved are not completely understood. In this paper, cranberry phenolic compounds and their potential microbial-derived metabolites (such as simple phenols and benzoic, phenylacetic and phenylpropionic acids) were tested for their capacity to inhibit the adherence of uropathogenic Escherichia coli (UPEC) ATCC®53503™ to T24 epithelial bladder cells. Catechol, benzoic acid, vanillic acid, phenylacetic acid and 3,4-dihydroxyphenylacetic acid showed anti-adhesive activity against UPEC in a concentration-dependent manner from 100-500 µM, whereas procyanidin A2, widely reported as an inhibitor of UPEC adherence on uroepithelium, was only statistically significant (p < 0.05) at 500 µM (51.3% inhibition). The results proved for the first time the anti-adhesive activity of some cranberry-derived phenolic metabolites against UPEC in vitro, suggesting that their presence in the urine could reduce bacterial colonization and progression of UTI.