Our environment is contaminated with a diverse array of chemicals; one of which is definitely polycyclic aromatic hydrocarbons (PAHs). settings. Also, a decrease in the percentage of cells in the H and G2 phases compared to G1 phase of cell cycle was mentioned when cells were treated with BaP and FLA collectively, compared to individual FLA treatment. The rate of FLA rate of metabolism was more when cells were uncovered to FLA in combination with BaP, compared to FLA alone. The enhanced biotransformation of FLA as a result of concomitant exposure to BaP may have implications for colon cancer risks arising from human dietary exposure to PAH mixtures through consumption of barbecued meat. test. The criterion for statistical significance was set at < 0.05. 3. Results 3.1. BaP does not modulate the effect of FLA on cell growth Fig. 1 represents profiles from GSK-923295 supplier growth assays of HT-29 cells following FLA, and BaP + FLA exposure. No significant change was observed in each cell cycle phase among the various exposure concentrations from BaP exposure alone. No significant changes were observed among the time points and exposure concentrations in cells uncovered to FL alone, except the 25 M concentration at 96 h. Cells uncovered to 25 M BaP + FLA exhibited a significant reduction in growth at 96 h. Fig. 1 Growth of HT-29 colon cells uncovered to or fluoranthene (FLA) or a combination of benzo(a)pyrene (BaP) and fluoranthene. HT-29 cells were treated with the above-mentioned toxicants at 1, 5, 10 and 25 M for 24, 48, 72 and GSK-923295 supplier 96 h. Post exposure to ... 3.2. BaP enhances the cytotoxicity of FLA GSK-923295 supplier Fig. 2 reveals the cytotoxicity of BaP and FLA to HT 29 cells. Mouse monoclonal antibody to Annexin VI. Annexin VI belongs to a family of calcium-dependent membrane and phospholipid bindingproteins. Several members of the annexin family have been implicated in membrane-relatedevents along exocytotic and endocytotic pathways. The annexin VI gene is approximately 60 kbplong and contains 26 exons. It encodes a protein of about 68 kDa that consists of eight 68-aminoacid repeats separated by linking sequences of variable lengths. It is highly similar to humanannexins I and II sequences, each of which contain four such repeats. Annexin VI has beenimplicated in mediating the endosome aggregation and vesicle fusion in secreting epitheliaduring exocytosis. Alternatively spliced transcript variants have been described An exposure concentration-dependent increase in cytotoxicity was noticed for individual exposures of FLA at 48 and 72 h post exposure compared to 24 h. The 10 and 25 M concentrations showed a statistically significant (< 0.05) increase in cytotoxicity compared to the 1 and 5 M concentrations. The combined treatment of BaP and FLA showed a trend comparable to that of FLA individually but the cytotoxicity due to binary exposure was more pronounced than either one of them treated individually. Fig. 2 Cytotoxicity of HT-29 colon cells uncovered GSK-923295 supplier to FLA, and BaP + FLA. HT-29 cells were treated with the above-mentioned toxicants at 1, 5, 10 and 25 M for 24, 48, 72 and 96 h. Post exposure to toxicants, the cytotoxicity was assayed by using the lactate ... 3.3. BaP marginally increases the apoptotic effects of FLA in HT-29 cells Fig. 3 represents apoptosis profiles from Caspase 3 Analysis of HT-29 cells following FLA and FLA + BaP exposure respectively. No significant change was observed among the various exposure concentrations and time points. Fig. 3C represents the apoptosis profiles following exposure to BaP + FLA. There was no significant change in Caspase 3 activity among the exposure concentrations and time points except the 25 M concentrations at 72 h, which showed significant apoptosis compared to 1 M concentration of BaP + FLA. Fig. 3 Apoptosis of HT-29 colon cells uncovered to 1, 5, 10 and 25 M FLA, and BaP + FLA for 24, 48, 72 and 96 h. Apoptosis of cells were decided using the Caspase-3 assay kit. Data from triplicate determinations were used. 3.4. BaP alters the effects of FLA on the cell cycle profiles of HT-29 cells in a concentration-and time-dependent manner Fig. 4 represents cell cycle profiles from flow cytometry of HT-29 cells following FLA exposure. Except 24 h exposure to 1C25 M FLA concentration at G1 phase, FLA did not exhibit any noteworthy effect on HT-29 cell cycle. A reduction in the G2 phase was shown at all the exposure periods, indicating that FLA blocks the cell cycle progression at G2/M transitions. Fig. 4 Cell cycle changes in HT-29 colon cells uncovered to 1, 5, 10 and 25 M FLA for 24, 48, 72 and 96 h. Cell cycle changes were analyzed using the Fluorescence-Activated Cell Sorting (FACS). Data from triplicate determinations were used. Fig. 5 represents cell cycle profiles following exposure to equimolar concentrations of FLA + BaP. The dual exposure demonstrates a cell cycle arrest comparable to cells uncovered to BaP alone. The percent of HT-29 cells in the S phase showed an increase over 24C96 h. Unlike cells uncovered to BaP or FL alone, after 96 h there was a decrease in percent of cells treated with 10 M and 25 M concentrations in the G1 phase. From these results we.