The no-observed-adverse-effect level of phthalates promotes proliferation and cell cycle progression in normal human breast cells.

OBJECTIVE: The data on the association between phthalates and breast cancer risk remains inconsistent. This study aimed to explore the possible mechanism of low-dose exposures of phthalates, including Butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di(20ethylhexyl) phthalate (DEHP), on breast tumorigenesis. METHODS AND METHODS: MCF-10A normal breast cells were treated with phthalates (10 and 100 nM) and 17ß-estradiol (E2, 10 nM), which were co-cultured with fibroblasts from normal mammary tissue. Cell viability, cycle, and apoptosis were detected by MTT assay, flow cytometry, and TUNEL assay respectively. The expression levels of related proteins were determined by Western blot. RESULTS: Like E2, both 10 nM and 100 nM phthalates exerted significantly higher cell viability, lower apoptosis, and increased cell numbers in the S and G2/M phases with up-regulation of cyclin D/CDK4, cyclin E/CDK2, cyclin A/CDK2, cyclin A/CDK1, and cyclin B/CDK1, compared with the control group. Significant increase in PDK1, P13K, p-AKT, p-mTOR, and BCL-2 expression and a decrease in Bax protein, cytochrome C, caspase 8, and caspase 3 levels were noted in cells treated with 10 nM and 100 nM phthalates and E2, compared with the control group and MCF-10A cells co-cultured with fibroblasts. The effects of the three phthalates were noted to be dose-dependent. CONCLUSIONS: The results indicate that phthalates at a level below its no-observed-adverse-effect concentration, as defined by the current standards, still induce cell cycle progression and proliferation as well as inhibit apoptosis of normal breast cells. Thus, the possibility of breast tumorigenesis through chronic phthalate exposure should be considered.

Regulation of the cell cycle and P13K/AKT/mTOR signaling pathway by phthalates in normal human breast cells.

OBJECTIVE: To investigate the impact of phthalates, including Butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP), in breast carcinogenesis. MATERIALS AND METHODS: MCF-10A normal breast cells were treated with phthalates (100 nM) and 17ß-estradiol (E2, 10 nM), which were co-cultured with fibroblasts from normal mammary tissue adjacent to estrogen receptor positive primary breast cancers. Cell viability was determined using a 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Cell cycles were analyzed using flow cytometry. The proteins involving cell cycles and P13K/AKT/mTOR signaling pathway were then evaluated by Western blot analysis. RESULTS: MCF-10A co-cultured cells treated with E2, BBP, DBP, and DEHP exhibited a significant increase in cell viability using MTT assay. The expressions of P13K, p-AKT, and p-mTOR, as well as PDK1 expression, were significantly higher in MCF-10A cells treated with E2 and phthalates. E2, BBP, DBP, and DEHP significantly increased cell percentages in the S and G2/M phases. The significantly higher expression of cyclin D/CDK4, cyclin E/CDK2, cyclin A/CDK2, cyclin A/CDK1, and cyclin B/CDK1 in MCF-10A co-cultured cells were induced by E2 and these three phthalates. CONCLUSION: These results provide consistent data regarding the potential role of phthalates exposure in the stimulating proliferation of normal breast cells, enhancing cell viability, and driving P13K/AKT/mTOR signaling pathway and cell cycle progression. These findings strongly support the hypothesis that phthalates may play a crucial role in breast tumorigenesis.

Laser hair removal following forehead flap for nasal reconstruction.

The forehead flap is a dependable option for nasal reconstruction owing to its reliability and anatomic likeness to nasal skin. For patients with low hairlines, the vertical design of the paramedian forehead flap can intrude into the scalp, thus incorporating hair into the nasal reconstruction. The inadequate length of the forehead flap or shift to an oblique design may result in eyebrow elevation and asymmetry. Therefore, laser hair removal (epilation) on the forehead flap has been proposed to improve esthetic results. An alexandrite laser (755 nm, 10 to 20 ms, 18-mm spot size) with a Dynamic Cooling Device™ (DCD™) cooling system was used for hair removal in 22 patients (16 male and 6 female patients) after nasal reconstructions using forehead flaps from December 2011 to September 2016. All patients received cryogen spray cooling laser treatment (CSC-LT). The mean follow-up period was 24 months, with a range between 18 and 50 months. The average duration of treatment was 1.8 months (range, 1-5 months). The energy density ranged from 14 to 18 J/cm2 with an average of 17.2 J/cm2. The number of treatments ranged from 2 to 4 (mean 2.8). Patients had satisfactory esthetic results over 11.1 months (range, 8-18 months). Residual white hairs were observed in 3 patients, and 4 patients had tiny black residual hairs without deteriorating cosmesis. Using an alexandrite laser to remove hair on the forehead is safe and reliable in nasal reconstruction with superior recipient site cosmesis.

Effects of phytoestrogens on the activity and growth of primary breast cancer cells ex vivo.

AIM: To explore the ex vivo effects of phytoestrogens on primary human breast cancer cells. METHODS: Breast cancer cells were obtained from patients who underwent primary breast cancer surgery, which were treated with 10-8 M 17ß-estradiol (E2 ), one of three phytoestrogens (genistein, resveratrol and quercetin, 10-7 M), and a combination of E2 and one of the three phytoestrogens for 48 h. These cells were then extracted for viability and apoptosis assay. The proteins involved in the proliferative and apoptotic pathways were evaluated by western blot analysis. RESULTS: Human breast cancer cell viability was inhibited by all phytoestrogens but induced by E2 with or without phytoestrogen. Apoptotic cells, as well as the proteins involved in apoptotic pathway and estrogen receptor (ER) ß, were significantly increased in the cells treated with phytoestrogen alone. The use of E2 with or without a phytoestrogen revealed completely opposite results. The proteins involved in the proliferative pathway and ER α expression were all increased in the cultures with E2 with or without phytoestrogens. CONCLUSION: In the presence of E2 , these phytoestrogens lose the effects of suppressing breast cancer cells; contrastingly, induce growth stimulatory effects by inhibiting apoptosis and stimulating proliferation in primary breast cancer cells. Thus, the effects of phytoestrogens on breast cancer should be considered as E2 still present in breast cancer tissue.

Effects of phthalates on normal human breast cells co-cultured with different fibroblasts.

Whether or not phthalates play a role in breast carcinogenesis remains to be determined. The goal of this study was to explore the effects of phthalates on the growth of normal MCF-10A breast cells modulated by breast fibroblasts. Fibroblasts were derived from normal mammary tissue adjacent to both estrogen receptor (ER) positive and negative primary breast cancers, which were grown separately from nontumorigenic MCF-10A epithelial cells. MCF-10A co-culture cells were treated with 10 nM 17ß-estradiol (E2), Butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di(20ethylhexyl) phthalate (DEHP) (10 and 100 nM). After incubation for 120 hours, the cells were harvested and extracted for MTT assay. Western blot analysis was used to evaluate the proliferative pathway proteins and the effects on ER α. Only fibroblasts from ER (+) breast cancer significantly stimulated proliferation of MCF-10A cells. Exposure of the co-culture to E2, BBP, DBP, DEHP, and E2 combined with one of these phthalates resulted in significantly increased cell proliferation, as well as proliferating cell nuclear antigen (PCNA) and ER α expressions. The present study demonstrates that phthalates express a significant influence in fibroblast-epithelial interactions, similarly to the effects of E2 on breast cells. The effects of phthalates on normal breast cells depend upon ER modulating actions. In breast carcinogenesis, phthalates should be considered as having endocrine disrupting potential, even at low concentrations.

Impact of low concentrations of phthalates on the effects of 17ß-estradiol in MCF-7 breast cancer cells.

OBJECTIVE: To explore whether lower concentrations of phthalates interfere with the effects of 17ß-estradiol on the growth of MCF-7 breast cancer cells. MATERIALS AND METHODS: MCF-7 cells were treated with 17ß-estradiol (E2), phthalates, including butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di(20ethylhexyl) phthalate (DEHP), or with both E2 and phthalates, all at 10nM. After incubation for 48 hours, the cells were harvested and extracted for MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The proteins involving proliferative and apoptotic pathway were then evaluated using Western blot analysis. RESULTS: In MCF-7 cell cultures, the MTT assay revealed a significant increase in cell viability with E2 and these three phthalates, and significantly more cell proliferation with the combination of E2 and phthalates. Proliferating cell nuclear antigen, as well as phosphatidylinositide 3-kinase (PI3K) and p-Akt, were all substantially increased in cultures with E2, phthalates, and the two combined. An additive effect of phthalates on the obvious increase of Bcl-2 and ER α expression was also noted in the presence of E2. CONCLUSION: The present study demonstrates that even at a very low concentration, BBP, DBP, and DEHP were not only still capable of displaying estrogenic activity, but also of inducing an additive proliferative effect through the PI3K/Akt signaling pathway and preventing apoptosis in the presence of E2. Therefore, the effects of current reference doses for phthalates defined by the government, especially for premenopausal women, should be further considered.

Effects of estradiol and progestogens on human breast cells: regulation of sex steroid receptors.

OBJECTIVES: To examine the effects of 17ß-estradiol (E2) and progestogens, used in hormone therapy, on estrogen receptors (ER), progesterone receptors (PR), and human breast tumor cell growth. MATERIALS AND METHODS: MCF-7 cells were incubated in pure E2 (1 nM and 10 nM) as well as in E2 in conjunction with 10 nM progestogens, including progesterone (P4), medroxyprogesterone acetate (MPA), norethisterone acetate (NET), and cyproterone acetate (CPA). Cell proliferation, apoptosis, expression of caspase-3, and both ER and PR isoforms were evaluated. RESULTS: Caspase-3 was significantly diminished in cultures with only E2, whereas ERα significantly increased. A significant increase of caspase-3 in addition to the entire abolishment of E2-induced augmentation of ERα was observed in 1 nM E2 plus MPA and 10 nM E2 plus NET, whereas PR isoform B (PRB) was significantly increased. The ratios of apoptosis: proliferation significantly increased in 1 nM E2 plus progestogens (except P4) and 10 nM E2 plus NET. The changes of the PRA/PRB ratio were inversely related to the changes of the apoptosis to proliferation ratio. Significant increase of ERß and PRB was noted in the E2 plus MPA or NET, in addition to a significant increase of ERα and decrease of PRA in the E2 plus CPA, as well as an increase of ERα and decrease of PRA and PRB in the E2 plus P4. CONCLUSIONS: The combination of E2 and various progestogens resulted in diverging effects on ERs and PRs expressions, which induced different effects on MCF-7 cell growth. Compared with P4, aberrant hormone and biological activity of synthetic progestin, by way of altered receptor expression, may be an important factor in affecting breast cell growth.