Irradiation of murine hepatoma 1c1c7 cultures presensitized with N-aspartyl chlorin e6 (NPe6) caused lysosomal disruption and apoptosis. Tao cells, a variant of the 1c1c7 line having lower aryl hydrocarbon receptor (AhR) contents, were resistant to the pro-apoptotic effects of NPe6 in the same photodynamic therapy protocol. Colony-forming assays were used to establish light dose-dependent and NPe6 concentration-dependent cytotoxicity curves. Lysosomal breakage and cell survival paralleled one another in both cell types. When analyzed at comparable lethal dose conditions, the onset of apoptosis was delayed, and the magnitude of the apoptotic response was muted in Tao cells, as assessed by morphology, annexin V binding, caspase-3 activities, and analyses of Bid, procaspase-9, and pro-caspase-3 cleavage. In contrast, the kinetics/magnitude of pro-caspase-3 activation in the two cell lines were identical after exposure to HA14 -1 or Jo2 antibody, inducers of the intrinsic and extrinsic apoptotic pathways, respectively. Tao endosomal/lysosomal extracts contained ϳ50%, 35%, and 55% of the Bid cleavage and cathepsin B and

Recent studies suggest that the aryl hydrocarbon receptor (AhR) modulates susceptibilities to some pro-apoptotic agents. AhR-containing murine hepatoma 1c1c7 cultures underwent apoptosis following exposure to tumor necrosis factor-␣ (TNF␣) ؉ cycloheximide (CHX). In contrast, Tao

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Because of a lack of information of the optimum nutritional requirements, epithelial cells derived from normal human prostate and prostate tumors have been difficult to propagate in vitro, which hinders research in prostate carcinogenesis. In an effort to establish optimum nutritional conditions and differences in growth characteristics of normal human prostate (NP), benign prostatic hyperplasia (BPH), and prostatic carcinoma (PCA), we have compared the effects of several growth factors on cell proliferation and elucidated growth properties of low passage epithelial cells derived from NP, BPH, and PCA of an African-American patient. Primary and low passage cultures were propagated in serum-free keratinocyte basal medium (KBM) supplemented with insulin (5 micrograms/ml), hydrocortisone (0.5 microgram/ml), epidermal growth factor (EGF, 10 ng/ml), bovine pituitary extract (BPE; 50 micrograms/ml), cholera toxin (10 ng/ml), and antibiotics. Almost all NP, BPH, and PCA cells were positive for cytokeratins and prostate-specific antigen (PSA). The NP, BPH, and PCA cells were essentially diploid and lacked mutations in c-K-ras and c-Ha-ras oncogenes, and p53 tumor suppressor gene. However, they exhibited progressively accelerating growth parameters. The population doubling times of NP, BPH and PCA were 51 hr, 37 hr, and 29 hr, respectively; their saturation densities were 2.9 x 10(4)/cm2, 3.3 x 10(4)/cm2, and 7.2 x 10(4)/cm2, respectively. The NP and BPH cells required all of the growth factors in the medium, as deletion of any one of the above factors strongly inhibited their growth. The PCA cells, however, were independent of EGF and hydrocortisone. PC-3, an established human prostate cancer cell line, was independent of the growth factors tested. Fetal bovine serum (FBS) inhibited the growth of NP, BPH and PCA cells. In contrast, FBS stimulated the growth of the PC-3 cells in a concentration-dependent manner. These results indicate that in the absence of any apparent karyotype alterations and mutations in c-K-ras, c-Ha-ras and p53 genes, epithelial cells derived from NP, BPH, and PCA exhibit significant differences in their growth properties and responses to growth factors. These variations may represent early changes involved in prostate cancer, while gene mutations and cytogenetic alterations occur in advanced and/or metastatic tumors.

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The therapeutic usefulness of the quinoxaline derivatives XK469 (2-{4-[(7-chloro-2-quinoxalinyl)oxy]phenoxy}propionic acid) and SH80 (2-{4-[(7-bromo-2-quinolinyl)oxy]phenoxy}propionic acid) has been attributed to their abilities to induce G 2 /M arrest and apoptotic or autophagic cell death. Concentrations of XK469 or SH80 Ն 5 M were cytostatic to cultures of the normal murine melanocyte cell line Melan-a. Higher concentrations caused dosedependent cytotoxicity. Concentrations Ն10 M provoked dramatic morphological changes typified by marked increases in cell size and granularity. XK469/SH80-treated cultures accumulated tetraploid (4N) DNA-containing cells within 24 h of treatment, an 8N population within 3 days, and a 16N population within 5 days.

The endocrine disruptor Bisphenol A (BPA) is ubiquitous in both aquatic and surface sediment environments because it is continuously released into sewage wastewater effluent. The measurement of BPA at wastewater treatment plants is rarely performed even though the United States Environmental Protection Agency (EPA) states that current levels of environmental BPA could be a threat to aquatic organisms. Therefore, the aims of this study were to measure BPA levels in sewage wastewater at different collection points over a 1-year period and to compare the levels of BPA to 8-isoprostane, a human derived fatty acid, found in sewage wastewater. We analyzed pre-treated sewage samples collected from three source points located in different communities in the metropolitan Detroit area provided by the Detroit Water and Sewerage Department. Human urine samples were also used in the study. BPA and 8-isoprostane were measured using ELISA kits from Detroit R&D, Inc. BPA levels from the same collection point oscillated more than 10-fold over 1 year. Also, BPA levels fluctuated differentially at each collection point. Highly fluctuating BPA values were confirmed by LC/MS/MS. The concentration of BPA in sewage wastewater was ~100-fold higher than the concentration of 8-isoprostane, while urinary concentration was ~20-fold higher. Thus, BPA levels discharged into the sewage network vary among communities, and differences are also observed within communities over time. The difference in BPA and 8-isoprostane levels suggest that most of the BPA discharged to sewage wastewater might be derived from industries rather than from human urine. Therefore, the continuous monitoring of BPA could account for a better regulation of BPA release into a sewage network.