Subscriber access provided by READING UNIV
Environmental Measurements Methods
Multi-parameter phenotypic profiling in MCF-7 cells for assessing the toxicity and estrogenic activity of whole environmental water Wenlong Wang, Mitsuru Tada, Daisuke Nakajima, Manabu Sakai, Minoru Yoneda, and Hideko Sone Environ. Sci. Technol., Just Accepted Manuscript • DOI: 10.1021/acs.est.8b01696 • Publication Date (Web): 20 Jul 2018 Downloaded from http://pubs.acs.org on July 22, 2018
Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.
Page 1 of 27
Environmental Science & Technology
1
Title:
2
Multi-parameter phenotypic profiling in MCF-7 cells for assessing the toxicity and
3
estrogenic activity of whole environmental water
4 5
Author names: Wenlong Wang1,2, Mitsuru Tada3, Daisuke Nakajima1, Manabu Sakai4,
6
Minoru Yoneda2, Hideko Sone1*
7 8 9 10
Author affiliations: 1. Center for Environmental Risk Research, National Institute for
11
Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8606, Japan;
12
2. Department of Environmental Engineering, Graduate School of Engineering, Kyoto
13
University, Katsura, Nishikyo-ku, 615-8540, Kyoto, Japan
14
3. Center for Health and Environmental Risk Research, National Institute for
15
Environmental Studies, Tsukuba, Ibaraki, Japan
16
4. Yokohama Environmental Research Institute, 1-2-15, Takigashira, Isogo Ward,
17
Yokohama City 235-0012, Japan
18 19 20
Corresponding Author’s Address: Hideko Sone, Research Center for Environmental
21
Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki
22
305-8506, Phone: +81-29-850-2464, FAX: +81-29-850-2546; e-mail:
[email protected] 23 24
ACS Paragon Plus Environment
Environmental Science & Technology
Page 2 of 27
25
ABSTRACT
26
Multi-parameter phenotypic profiling of small molecules is a powerful approach to their
27
toxicity assessment and identifying potential mechanisms of actions. The present study
28
demonstrates the application of image-based multi-parameter phenotypic profiling in
29
MCF-7 cells to assess the overall toxicity and estrogenic activity of whole
30
environmental water. Phenotypic profiling of 30 reference compounds and their
31
complex mixtures was evaluated to investigate the cellular morphological outcomes to
32
targeted biological pathways. Overall toxicity and estrogenic activity of environmental
33
water samples were then evaluated by phenotypic analysis comparing with conventional
34
bioassays and chemical analysis by multivariate analysis. The phenotypic analysis for
35
reference compounds demonstrated that size and structure of cells related to biological
36
processes like cell growth, death, and communication. The phenotypic alteration and
37
nuclei intensity were selected as potential biomarkers to evaluate overall toxicity and
38
estrogenic activities, respectively. The phenotypic profiles were associated with the
39
chemical structure profiles in environmental water samples.Since the phenotypic
40
parameters revealed multiple toxicity endpoints, it could provide more information that
41
is relevant to assessing the toxicity of environmental water samples in compare with
42
conventional bioassays.
43
analysis with MCF-7 cells provides a rapid and information-rich tool for toxicity
44
evaluation and identification in whole water samples.
45
KEYWORDS:
46
identification, estrogenic activity, whole environmental water
In conclusion, the image-based multi-parameters phenotypic
multi-parameter
phenotypic
analysis,
47 48
ACS Paragon Plus Environment
toxicity
evaluation
and
Page 3 of 27
Environmental Science & Technology
49
TOC
50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
ACS Paragon Plus Environment
Environmental Science & Technology
68
INTRODUCTION
69
Environmental contaminants, covering vast categories of chemicals such as estrogens,
70
pharmaceuticals, pesticides, and heavy metals, are ubiquitous in aquatic environments,
71
posing high risks for ecosystems and human health.1-3 Wastewater effluent is a major
72
source of the contaminants and induces adverse health effects through acting on broad
73
biological pathways, including G protein-coupled receptor signaling,4 DNA damage,5
74
neurotoxicities,6 and endocrinologies/hormones.7 The complex toxicity mechanisms of
75
the pollutants and their uncertain impacts have increased public concern for effluent
76
toxicity evaluation as a whole. To clarify, the toxicity mechanisms make it challenging
77
for toxicity identification in whole wastewater samples.
78
Various bioassays have been applied for overall toxicity evaluation, assaying the
79
lethal effects on mammal cell lines such as HepG2 cells8 and whole organisms such as
80
microbes,9 microalgae,10 Magna,11 and fish.12,
81
limitations such as: (i) ambiguity between toxic effects and mechanisms of actions, (ii)
82
middle or low-screening throughput capacity, and (iii) poor portability to humans,
83
which limits understanding of the mechanisms of toxicity. A battery of bioassays was
84
therefore performed targeting various endpoints for toxicity evaluation and
85
identification but this tends to be time-consuming.14,15 Multi-parameter transcription
86
profiling and protein profiling were employed for toxicity evaluation and identification
87
of environmental samples, however, the significant costs limited large-scale screening.
88
Therefore, biological pathway-abundant and cost-efficient approaches are clearly
89
required for the evaluation and identification of toxicity in environmental samples.
13
But the methods have various
90
Image-based phenotypic analysis is a robust and cost-efficient approach for
91
identifying small molecules through cellular morphology modifications related to
ACS Paragon Plus Environment
Page 4 of 27
Page 5 of 27
Environmental Science & Technology
92
specific mechanisms of action.16-18 Evidence has indicated correlations between
93
morphological changes and mechanisms of compounds, thus making it feasible to
94
predict chemical mechanisms or toxicity using phenotypic similarity.19 The construction
95
of a morphological database of compounds illustrated the relevance between mechanism
96
similarity and phenotypic similarity and in turn, suggested a novel method to identify
97
mechanisms of action or toxicity of compounds using morphological profiles. Yet this
98
technology has been restricted to drug discovery owing to the small scale of the
99
chemicals database and a lack of clear biological relevance.20 Cellular receptors (e.g.,
100
estrogen receptors, G protein-coupled receptors ) or growth processes (e.g., apoptosis
101
and cellular proliferation) are frequently used as endpoints for toxicity assessment of
102
environmental contaminants and water samples,21,
103
correlations with morphological effects.19 On this premise, we hypothesized that
104
environmental contaminants with different biological mechanisms would exhibit
105
specific phenotypic effects and their toxicity in environmental water samples can be
106
preliminarily screened and identified by multi-parameter phenotypic analysis.
22
and were reported to exhibit
107
To test our hypothesis, we investigated the phenotypic responses to targeted
108
biological pathways through exposure to 30 reference compounds and complex
109
mixtures (e.g., pharmaceuticals, pesticides, and estrogens), and then aimed to assess the
110
overall toxicity and estrogenic activity of whole water samples through the phenotypic
111
analysis. The MCF-7 cell line was selected because it has been widely applied to
112
evaluations of estrogenic activities such as E-screen.23 Morphological parameters were
113
selected as endpoints to assess the overall water toxicity and estrogenic activity of
114
whole water samples compared with conventional toxicity bioassays (MTT assay, direct
115
nuclei count) and estrogenic activity evaluation methods (E-screen, ELISA,
ACS Paragon Plus Environment
Environmental Science & Technology
Page 6 of 27
116
LC-qTOF-MS). The image-based multi-parameters phenotypic analysis with the cells
117
provides a rapid and information-rich tool for toxicity evaluation and identification in
118
whole water samples.
119 120
MATERIAL AND METHODS
121
Chemicals. Table 1 shows the pharmaceuticals, pesticides, estrogens, and ions
122
selected for this study based on biological pathways. All the pharmaceuticals were
123
purchased from the SCREEN-WELL® Cardiotoxicity library (BML-2850, ENZO Life
124
Sciences, Farmingdale, USA). The other chemicals were obtained from Wako Pure
125
Chemical Industries, Ltd. (Osaka, Japan). Dimethyl sulfoxide (DMSO) was used as the
126
primary solvent, with solutions further diluted in cell culture media before use. The final
127
concentration of DMSO in the medium did not exceed 0.1% (v/v). The compounds were
128
mixed at the average ratios as following: M1, a mixture of chemicals acting on the
129
neurotoxicity pathway including IMI, ACE, CAR, CPS, THD, DDT; M2, a mixture of
130
chemicals acting on the endocrinology/hormones pathway including E2, BPA, TAM;
131
M3, a mixture of chemicals acting on membrane transporter/ion channel pathway
132
including AMI, BEP, FLE, CARB; M4, a mixture of environmental chemicals; M5, a
133
mixture of pharmaceuticals; M6, a mixture of all chemicals; M7, a mixture of
134
pharmaceuticals excluding DGT; M8, a mixture of all chemicals excluding DGT.
135
Cell culture. Human breast cancer cells (MCF-7) were obtained from the American
136
Type Culture Collection (Manassas, VA, USA). The cells were cultured in Dulbecco’s
137
modified
138
(Sigma-Aldrich, Japan) supplemented with 10% fetal bovine serum (FBS) (HyClone,
139
USA). The cells cultures were maintained at 37°C in a 5% CO2 humidified incubator.
Eagle’s
medium
and
Nutrient Mixture
ACS Paragon Plus Environment
F-12
Ham (DMEM-F12)
Page 7 of 27
Environmental Science & Technology
140
Sampling preparation and treatment. Water samples (500 mL) were collected at 8
141
river locations and 6 wastewater treatment plants (WWTP) within one river basin in the
142
Kanto area of Japan from July 3 to August 7, 2014. The 15 water samples included
143
wastewater treatment plant effluents (W1-Eff, W2-Eff, W3-Eff), wastewater treatment
144
influents (W1-Inf, W2-Inf, W3-Inf), upstream river water (T2, T7), middle stream river
145
water (T3, T8, T9), downstream river water (T4), and river water from an estuary (T5,
146
T6) (Figure S1). For cell exposure experiments, 50 mL of each sample was filtered
147
through a 0.22 µm polyethersulfone (PES) membrane (Millipore, Germany) and stored
148
at −20 °C before use. The filtered water samples were mixed with 10× concentrated
149
DMEM-F12 medium (1:9), and adjusted to a pH of 7.2–7.4 with a sodium bicarbonate
150
solution [7.5% w/v] after adding 10% fetal bovine serum (FBS). The remaining water in
151
each sample (400 mL) was extracted by Autoprep EDS-1 (SHOWA DENKO, Japan)
152
and eluted with methanol. After the eluate was evaporated to dryness with a nitrogen
153
stream, the residue was dissolved with 1mL of DMSO for enzyme-linked
154
immunosorbent
155
chromatography/quadrupole time-of-flight mass spectrometry (LC-qTOF-MS).
assays
(ELISA)
and
high-performance
liquid
156
Image-based phenotypic analysis. 1) Exposure setup. MCF-7 cells (1000 cells/well
157
in 200 µL DMEM-F12) were plated in 96-well plates. After 24 h, triplicate samples of
158
cells were exposed to single compounds ranging from 10-12 M to 10-6 M, mixtures or
159
whole water medium for 6 days in preparation for the staining. 2) Immunofluorescence.
160
After a 6-day exposure, the cells were fixed with 4% paraformaldehyde (Wako, Japan)
161
for 15 min, treated with 0.1% TritonX-100 (Wako, Japan) for 30 min, and incubated
162
with 1% BSA-PBS for 30 minutes at room temperature. The samples were stained with
163
2% Phalloidin (546 A2228; Red) (Life Technologies, USA) for 1 h and 2 µg/ml
ACS Paragon Plus Environment
Environmental Science & Technology
164
Hoechst (33342; Blue) (DOJINDO, Japan) for 15 minutes at room temperature. 3)
165
Image Acquisition. Typical microphotographs were obtained using an Olympus LV1200
166
High-Performance Laser Scanning Microscope (Olympus, Japan). For image-based
167
analysis, immunofluorescence images (9 fields per well of a 96-well plate) were
168
acquired automatically on an IN Cell Analyzer 1000 (GE Healthcare, UK) using a 4× or
169
10× objective. A laser autofocus system analyzed at least 1000 cells in each well.
170
Hoechst-positive nuclei and phalloidin-positive cell cytoskeletons were recognized
171
using IN Cell Developer Software (GE Healthcare, UK). 4) Data processing. To
172
characterize the phenotypic responses of the cells, 13 phenotypic parameters of the cells
173
and their nuclei (intensity, perimeter, major, minor, minor/major, area, and form factor)
174
were quantified with the IN Cell Developer Tool Box 1.7 (GE Healthcare, UK). The
175
morphological parameters of the cells (n > 1000) were averaged and normalized to
176
those of a negative control. The normalized multi-parameter data were then determined
177
with a PCA, and the resulting principal components were displayed on a 2D score plot.
178
The “Euclidean distance” of each treatment from the control was calculated using a
179
distance formula. A detailed description of the procedure is provided in Figure S2.
180
Conventional bioassays. Two methods, an MTT (3-(4, 5-dimethyl thiazolyl-2)-2,
181
5-diphenyltetrazolium bromide) assay and direct cell counting, were used to assess cell
182
viability. An E-screen assay based on the protocol developed by Soto (1995) was used
183
to calculate the estrogen equivalent concentration (EEQ) in river water and wastewater
184
during a 6-day exposure to MCF-7 cells.24 The 17ß-estradiol (E2) concentration was
185
measured with an estradiol enzyme immunoassay (EIA) kits (Cayman Chemical, USA).
186
Five-hundred-microliters samples of a concentrated solution equivalent to 200 mL
ACS Paragon Plus Environment
Page 8 of 27
Page 9 of 27
Environmental Science & Technology
187
water samples were used for triplicate ELISAs. The detailed bioassay protocols are
188
provided in Supporting Information Text S1.
189
Non-targeted LC-qTOF-MS analysis. A non-target chemical analysis was
190
completed with an LC (Agilent 1200 series, USA) coupled to a Q-TOF-MS (Agilent
191
6540 UHD Accurate-Mass, USA) and electrospray ionization (ESI) source with positive
192
and negative modes. Chromatography was performed with a reversed-phase column
193
(ZORBAX Extend-C18, 5 µm, 2.1 × 150 mm, Agilent, USA) with the injection volume,
194
flow rate, and temperature set to 5 µL, 0.2 mL/min, and 40°C, respectively. The mass
195
spectra were collected in full-scale mode from 50–2000 m/z. The data were assessed
196
with MassHunter Qualitative Analysis software (MPP, version 12.0, Agilent, USA)
197
software for the detection of molecular features followed by Agilent Mass Profiler
198
Professional Software. The raw data were normalized with a quantile algorithm using
199
GeneSpring v14.5 (Agilent, USA), and chemicals with a significant difference (fold
200
change > 2, P < 0.05, n=500) were selected for multivariate statistical analyses,
201
including hierarchical clustering and PCA.
202
Statistical Analysis. The data from phenotypic and non-target analyses were used in
203
a PCA to evaluate the differences in phenotypic and chemical profiles among the
204
samples. An OPLS-DA was performed to identify chemical candidates that exhibited
205
high correlations with the phenotypic parameters. The PCA and OPLS-DA were
206
performed using SIMCA 13 software (Umetrics, Sweden). Quantitative data were
207
expressed as the fold change vs. the control value ± standard deviation (SD). Statistical
208
significance was determined using a one-way analysis of variance (ANOVA) followed
209
by the Dunnett’s test for pairwise comparisons. Differences were considered statistically
210
significant at P < 0.05.
ACS Paragon Plus Environment
Environmental Science & Technology
Page 10 of 27
211 212
RESULTS AND DISCUSSION
213
Phenotypic profiling of MCF-7 cells treated with single compounds. The
214
dose-dependent effects on the cellular phenotype were measured for 30 compounds
215
acting on diverse biological pathways (Table 1). Endocrine disrupting chemicals
216
(EDCs) normally induce non-monotonic dose-responses (NMDRs) because they bind
217
mainly to estrogenic receptors (ERs) at low doses but may interact with other receptors
218
at high doses.25 17ß-estradiol (E2) at a low-dose range (10-14 M to 10-9 M) was used as a
219
model compound for assessing the morphological relevance of estrogenic activities, by
220
merit of its sensitivity to ER in MCF-7 cells.26 E2 induced a dose-independent response
221
in phenotypic parameters (Figure S3B), and a correlation between cellular phenotype
222
(intensity and area) and cell proliferation (Figure S4) revealed the strong potential of
223
these parameters for the evaluation of an estrogenic effect. The phenotypic responses to
224
numerous biological pathways were investigated by exposing the cells to 26 selected
225
organic compounds at a wide range of doses from 10-12 M to 10-6 M. NMDRs were
226
elicited
227
di(2-ethylhexyl)phthalate (DEHP); the pharmaceuticals lisinopril (LIS), quinidine
228
(QUI), propranolol (PH), bepridil (BEP), and prednisone (PSE); and the pesticides
229
acetamiprid (ACE) and thalidomide (THD) (Figure S5 and S6). Exposure to the
230
compounds LIS, QUI, AMI, PSE, and THD elicited phenotypic characteristics similar
231
to those observed after E2 exposure (increased intensity but decreased areas of both the
232
nuclei and cell). The diverse phenotypic effects of ACE (increased cell area), BPA
233
(decreased nuclei intensity), and DEHP (decreased nuclei intensity and increased cell
234
area) may have stemmed from interactions with other toxicity pathways. Digitoxin
by
exposure
to
the
well-known
EDCs
ACS Paragon Plus Environment
bisphenol
A
(BPA)
and
Page 11 of 27
Environmental Science & Technology
235
(DGT) at a high dose (10-7 M) induced abnormal cells (synaptic cells) (Figure S10A)
236
exhibiting a significantly decreased cell area but larger cell major (Figure 1). The
237
influence of inorganic chemicals (K, Ca, Na, Mg) and osmotic pressure (PBS) were
238
considered owing to the downstream whole water sample exposure, and the
239
PBS-induced remarkable larger cell shape may have resulted from change in the
240
osmotic pressure (Figure 1 and Figure S10B).
241
Phenotypic profiling of MCF-7 cells treated with chemical mixtures. Similar
242
acting compounds were mixed (M1 to M3) at the average ratios for phenotypic analysis
243
to investigate the feasibility of the analysis to characterize the toxicity of complex
244
mixtures. Otherwise, cells were exposed to mixtures including or excluding the
245
phenotype-active compound DGT (M5, M6 or M4, M7, M8, respectively) for toxicity
246
or chemical identification in complex mixtures. The compound mixtures induced
247
diverse phenotypic variations (Figure 2). M2 with estrogenic-active compounds induced
248
phenotypic effects similar to those brought about by the previous E2 exposure
249
(increased nuclei intensity, decreased cell area), which proved the feasibility of the
250
phenotypic analysis for characterizing estrogenic effects. We were interested to find that
251
mixtures with DGT (M5 and M6) also induced cellular abnormalities (echinoid spikes),
252
while the cells exposed to mixtures excluding DGT (M7 and M8) did not (Figure 2A).
253
These findings indicate that phenotype-active compounds or toxicities induce similar
254
phenotypic effects in complex mixtures, as well. In reverse, the compounds or toxicities
255
can be identified on the basis of phenotypic similarity in phenotypic analyses.
256
Phenotypic effects of whole water samples on MCF-7 cells. The MCF-7 phenotype
257
showed several variations after exposure to wastewater and river water (Figure 3A). The
258
vehicle control cells were round and equal-side angle in shape (Figure 3A-a), whereas
ACS Paragon Plus Environment
Environmental Science & Technology
259
the cells exposed to wastewater or river water were malformed into shrunk and
260
aggregated cells (W1-Eff and W3-Inf exposure) (Figure 3A-b, e), synaptic cells
261
(W2-Eff, T1, and T3 exposure) (Figure 3A-d, f, g), and cells with enlarged nuclei and
262
cell bodies (T6 exposure) (Figure 3A-h). The morphological changes of MCF-7 cells
263
were classified into 3 categories: 1) shrunk or enlarged cells; 2) synaptic or polygonal
264
cells, and 3) rounded cells.
265
Most of the wastewater samples brought about increases in the nuclei intensity of
266
MCF-7 cells but negatively affected other parameters. The morphological changes in
267
the cells exposed to the different river water samples differed markedly: increased
268
nuclei intensity (T1-T3) and cell area (T4), increased nuclei area (T6), and decreased
269
nuclei form factor (T8) (Figure 3B). Nuclei intensity has been well applied as the
270
endpoint for cell cycle analysis, and evidence indicates that the G2 phase of cell cycle
271
induces increased nuclei intensity,27 which verifies the positive correlations of cell
272
proliferation and nuclei intensity. The nuclei intensity variation was higher in cells
273
exposed to whole water samples than in cells with single compounds exposure, which
274
may result from the induced greater cell proliferation after whole water exposure
275
(Figure 1 and 3B). Moreover, cellular apoptosis also induces nuclei intensity
276
increasing,28 and may happen after W1-Inf exposure (Figure 3C). The cells exposed to
277
T6, the sample taken from the estuary region, showed increases in both nuclei area and
278
cell area, the same changes brought about by osmotic pressure effect from PBS
279
exposure.
280
Phenotypic alteration as a biomarker for toxicity evaluation. The U.S ToxCast
281
Chemical Prioritization Program demonstrated that environmental toxicants act on
282
molecular targets (e.g., kinases, cellular receptors, DNA) affecting biological processes
ACS Paragon Plus Environment
Page 12 of 27
Page 13 of 27
Environmental Science & Technology
283
such as cell cycle, apoptosis, and DNA recombination.29 Biological processes induce
284
morphological variation (Table S2) and are applied in cell-based biosensors for toxicity
285
evaluation in water.30 As such, multiple phenotypic parameters related to various
286
biological processes can be expected to provide rich mechanistic information (e.g., cell
287
cycle, apoptosis, cell death) (Figure S9) that can be retained through multivariate
288
statistical analyses in the lower dimension to assessing the toxicity and mechanisms.31
289
In this study, we characterized phenotypic alteration by Euclidean distance in a PCA for
290
the toxicity evaluation of compounds and river waters. Speculating that EDCs binding
291
to other toxicity receptors posed toxicological complexity at a high-dose range in
292
NMDR,
293
high-concentration compounds or water samples may yield superior results.
we
hypothesized
that
a
multi-parameter
phenotypic
analysis
for
294
To characterize the phenotypic effects of compounds and whole water samples, we
295
investigated the phenotypic results by PCA (Figure 4) and calculated the Euclidean
296
distance for comparison with the cell viability (Figure 5 and Figure S5-8). Compounds
297
with different mechanisms of action induced diverse phenotypic effects and clustered
298
together in the PCA score plot. DGT, PH, TAM, DEHP, and TCDD at high doses (10-7
299
M or 10-6 M) were plotted outside the cluster, indicating remarkable phenotypic effects
300
(Figure 4A). DGT, PH, and TAM at 10-6 M induced reduced cell viability along with a
301
large phenotypic alteration. The cell viability was not altered after exposure to BEP,
302
BUS, PSE, CAR, DDT, DEHP, and TCDD at 10-6 M, whereas the alterations of the
303
cellular phenotype dramatically increased (Figure S5-6). Cell death by cell apoptosis
304
and necrosis has been typically measured for cytotoxicity analysis.32 These compounds
305
mainly induced enlarged cell areas and longer minor/major axes at 10-6 M, bringing
306
about a large phenotypic alteration that may result from necrosis -induced cell swelling
ACS Paragon Plus Environment
Environmental Science & Technology
307
(Figure 1).33 Yet the changes in cell viability at high doses diverged too little from
308
control to reflect the toxicity such as with exposure to BEP, BUS (Figure S5-6). Our
309
results suggest that multi-parameter phenotypic analysis was more accurate in profiling
310
the toxicity-based cellular outcome than cell viability, and therefore was more suitable
311
for toxicity evaluation in high-dose ranges comparing with conventional toxicity assays.
312
After we applied the phenotypic approach for whole water toxicity analysis, the
313
phenotypic responses of WWTP influent, WWTP effluent and river water were well
314
clustered and separated in the PCA score plot (Figure 4C). The Euclidean distance from
315
control was calculated and compared with the results of the cell viability analysis
316
(Figure 5). The phenotypic alteration was significant (W1-Inf, W3-Inf) and was reduced
317
after wastewater treatment processes (Figure 5A), however, the cell viability by MTT
318
assay and nuclei count analysis was inconsistent, with the former showing no effect and
319
the last showing dramatically increased cell viability (W1-Inf, W3-Inf) (Figure 5B). The
320
conventional cell viability analyses is difficult to distinguish cell death, cell survival and
321
cell proliferation with a single bioassay.34 Our results indicated that the multiple
322
phenotypic parameters exhibited relation to biological processes and provided
323
information-rich endpoints for whole water toxicity analyses.
324
Linking phenotypic responses and toxicity pathways for toxicity identification.
325
Image-based phenotypic analyses, are highly automatic, provide abundant information,
326
and are well applied to predict the potential mechanism of small molecules based on
327
phenotypic profiles.35, 36 Investigations of the phenotypic effects underlying toxicity
328
pathways, therefore, allow the prediction and characterization of toxicities. Among the
329
EDCs, the well-known androgen receptor antagonist and estrogen receptor agonist BPA
330
37
induced estrogenic actions such as decreased nuclei area and cell area, but the
ACS Paragon Plus Environment
Page 14 of 27
Page 15 of 27
Environmental Science & Technology
331
decreased nuclei intensity may result from coexisting anti-androgenic mechanisms.38
332
Evidence has shown that DGT elicits anti-proliferation activities39 and that the Na+/K+
333
ATPase-inhibition activities of DGT may induce both cell migration and cell adhesion40
334
characterizing synaptic cell membranes (Table S2). BPS exposure led to enlarged cell
335
shape, a change brought about by cell necrosis via increased osmotic pressure.41 The
336
results demonstrated the viability of multi-parameter phenotypic analysis for in-depth
337
toxicity characterization. The mixture effects demonstrated that the phenotypic effects
338
(increased nuclei intensity and decreased area) could serve as markers for estrogenic
339
activities. This result, together with the phenotypic similarity exposed to DGT and its
340
complex mixture, indicated the high-potential of phenotypic analysis for toxicity
341
identification. The phenotypic effects brought about by the toxicity pathways
342
demonstrated that the increased nuclei intensity and decreased area by water exposure
343
(all wastewater, T1-T3) could characterize the estrogenic activities. T3 exposure
344
induced synaptic cells by acting on cell communication, and the enlarged cell shape
345
induced by T4 and T6 exposure may have resulted from cell necrosis. Interestingly, T6
346
was sampled near an estuary (Figure S1) with high electrical conductivity (Table S3),
347
resulting in a high tolerance of MCF-7 osmotic stress in phenotypic profiles.42
348
Comparison of the phenotypic analysis, estrogenic activity assays, and
349
non-target chemical analysis for estrogenic activity prediction. We measured the
350
estrogenic activity of whole with conventional bioassays (E-screen assay and ELISA
351
assay), and analyzed the correlations among chemical profiles, estrogenic activities and
352
phenotypic parameters using an OPLS-DA model (Figure 6). W1-Inf, the influent with
353
the highest E2 concentration at 13.5 ng/L (equal to 5.5×10-11 M) (Figure 6A), induced
354
the highest increased nuclei intensity (fold change=1.47, Figure 3B). Otherwise, the
ACS Paragon Plus Environment
Environmental Science & Technology
355
nuclei intensity in the phenotypic parameters exhibited well clustered with EEQ and E2
356
in the plot of the scores, indicating that the nuclei intensity had relatively higher
357
correlations to the estrogenic effects (Figure 6B). Although we cannot exclude the
358
effects of inorganic chemicals on phenotype and cell proliferation (Figure S7) in the
359
present study, the results demonstrate the potential of applying phenotypic parameters
360
(nuclei intensity and area) for estrogenic activity evaluation in complex whole water
361
samples.
362
For contaminants in 6 water samples (W1-Inf, W1-Eff, W3-Inf, T2, T8, T9) with
363
different phenotypic variation, we characterized the overall chemicals profiles using
364
PCA (Figure 6C). The results showed that W1-Eff, W3-Inf, and T2 clustered whereas
365
T9, T8, and W1-Inf were distinct in the PCA plot. We also were interested to find a
366
similar distribution in the multivariate analysis of the cell phenotypic variation (Figure
367
4C). This similarity suggests that the chemical profiles may be correlated with the
368
phenotypic variation. This hypothesis and our mixture toxicity evaluation together
369
suggest that the phenotypic effects may have stemmed from unique chemicals in the
370
water samples. T8, for example, induced a dramatic decrease in the nuclei formfactor
371
(fold change=0.66) that may have been associated with the DNA-damaging effects of
372
one or more of 43 unique chemicals in this sample (Figure S11).43
373
In conclusion, we report that our in vitro multiple phenotypic analysis was correlated
374
with the toxicity pathways and provided rich information for integrated toxicity
375
evaluation and characterization in environmental water samples. The following study
376
should be performed to improve this phenotypic analysis in the future research:
377 378
1) A more massive morphological database to investigate phenotypic effects of toxicity pathways.
ACS Paragon Plus Environment
Page 16 of 27
Page 17 of 27
Environmental Science & Technology
379
2) Mechanism research to understand the correlations between phenotypic effects
380
and functional genes.
381
We believe that this method is a promising approach for environmental toxicity
382
evaluation and identification, as well as for the study of toxicity-phenotype-chemical
383
interactions and the constructing of a cell morphology database for environmental
384
contaminants.
385 386
ASSOCIATED CONTENT
387
Supporting Information
388
This material is available free of charge via the Internet at http://pubs.acs.org.
389
AUTHOR INFORMATION
390
Corresponding Author
391
*Phone/fax: +81-029-850-2464;
392
E-mail:
[email protected];
[email protected] 393
Notes
394
The authors declare no competing financial interest.
395
ACKNOWLEDGMENTS
396
This study was supported by a Grant-in-Aid for Scientific Research (A) 15H01749 to
397
HS. We thank Ms. Miyuki Yoneyama for performing the analyses of LC-qTOFMS and
398
Ms. Hiroko Nansai and Qin Zeng for carrying out the experimental operation
399
procedures of cell cultures.
400 401 402 403
REFERENCES 1. Ribeiro, E.; Ladeira, C.; Viegas, S., EDCs Mixtures: A Stealthy Hazard for Human Health? Toxics 2017, 5, (1).
ACS Paragon Plus Environment
Environmental Science & Technology
404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450
2. Casida, J. E., Pesticide Interactions: Mechanisms, Benefits, and Risks. J Agr Food Chem 2017, 65, (23), 4553-4561. 3. Kuster, A.; Adler, N., Pharmaceuticals in the environment: scientific evidence of risks and its regulation. Philos T R Soc B 2014, 369, (1656). 4. Wise, A.; Gearing, K.; Rees, S., Target validation of G-protein coupled receptors. Drug Discov Today 2002, 7, (4), 235-246. 5. Dixon, D. R.; Wilson, J. T., Genetics and marine pollution. Hydrobiologia 2000, 420, 29-43. 6. Jett, D. A., Neurotoxic Pesticides and Neurologic Effects. Neurol Clin 2011, 29, (3), 667-+. 7. Olsen, C. A.; Meussen-Elholm, E. T. M.; Hongslo, J. K.; Stenersen, J.; Tollefsen, K. E., Estrogenic effects of environmental chemicals: An interspecies comparison. Comp Biochem Phys C 2005, 141, (3), 267-274. 8. Hara-Yamamura, H.; Nakashima, K.; Hoque, A.; Miyoshi, T.; Kimura, K.; Watanabe, Y.; Okabe, S., Evaluation of Whole Wastewater Effluent Impacts on HepG2 using DNA Microarray-based Transcriptome Analysis. Environmental Science & Technology 2013, 47, (10), 5425-5432. 9. Han, Y. S.; Brown, M. T.; Park, G. S.; Han, T. J., Evaluating aquatic toxicity by visual inspection of thallus color in the green macroalga Ulva: Testing a novel bioassay. Environmental Science & Technology 2007, 41, (10), 3667-3671. 10. Zhang, L. J.; Ying, G. G.; Chen, F.; Zhao, J. L.; Wang, L.; Fang, Y. X., Development and application of whole-sediment toxicity test using immobilized freshwater microalgae Pseudokirchneriella subcapitata. Environ Toxicol Chem 2012, 31, (2), 377-386. 11. Antczak, P.; Jo, H. J.; Woo, S.; Scanlan, L.; Poynton, H.; Loguinov, A.; Chan, S.; Falciani, F.; Vulpe, C., Molecular Toxicity Identification Evaluation (mTIE) Approach Predicts Chemical Exposure in Daphnia magna. Environmental Science & Technology 2013, 47, (20), 11747-11756. 12. Ho, K. T.; Gielazyn, M. L.; Pelletier, M. C.; Burgess, R. M.; Cantwell, M. C.; Perron, M. M.; Serbst, J. R.; Johnson, R. L., Do Toxicity Identification and Evaluation Laboratory-Based Methods Reflect Causes of Field Impairment? Environmental Science & Technology 2009, 43, (17), 6857-6863. 13. Khanal, R.; Furumai, H.; Nakajima, F., Characterization of toxicants in urban road dust by Toxicity Identification Evaluation using ostracod Heterocypris incongruens direct contact test. Sci Total Environ 2015, 530, 96-102. 14. Rodrigues, E. S.; Umbuzeiro, G. D., Integrating toxicity testing in the wastewater management of chemical storage terminals - A proposal based on a ten-year study. J Hazard Mater 2011, 186, (2-3), 1909-1915. 15. Combes, R. D.; Balls, M., Integrated Testing Strategies for Toxicity Employing New and Existing Technologies. Atla-Altern Lab Anim 2011, 39, (3), 213-225. 16. Moffat, J.; Grueneberg, D. A.; Yang, X. P.; Kim, S. Y.; Kloepfer, A. M.; Hinkle, G.; Piqani, B.; Eisenhaure, T. M.; Luo, B.; Grenier, J. K.; Carpenter, A. E.; Foo, S. Y.; Stewart, S. A.; Stockwell, B. R.; Hacohen, N.; Hahn, W. C.; Lander, E. S.; Sabatini, D. M.; Root, D. E., A lentiviral RNAi library for human and mouse genes applied to an arrayed viral high-content screen. Cell 2006, 124, (6), 1283-1298. 17. Zanella, F.; Lorens, J. B.; Link, W., High content screening: seeing is believing. Trends Biotechnol 2010, 28, (5), 237-245.
ACS Paragon Plus Environment
Page 18 of 27
Page 19 of 27
Environmental Science & Technology
451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496
18. Xia, X. F.; Yang, J. A.; Li, F. H.; Li, Y.; Zhou, X. B.; Dai, Y.; Wong, S. T. C., Image-Based Chemical Screening Identifies Drug Efflux Inhibitors in Lung Cancer Cells. Cancer Res 2010, 70, (19), 7723-7733. 19. Young, D. W.; Bender, A.; Hoyt, J.; McWhinnie, E.; Chirn, G. W.; Tao, C. Y.; Tallarico, J. A.; Labow, M.; Jenkins, J. L.; Mitchison, T. J.; Feng, Y., Integrating high-content screening and ligand-target prediction to identify mechanism of action. Nature Chemical Biology 2008, 4, (1), 59-68. 20. Futamura, Y.; Kawatani, M.; Kazami, S.; Tanaka, K.; Muroi, M.; Shimizu, T.; Tomita, K.; Watanabe, N.; Osada, H., Morphobase, an Encyclopedic Cell Morphology Database, and Its Use for Drug Target Identification. Chem Biol 2012, 19, (12), 1620-1630. 21. Ihara, M.; Inoue, A.; Hanamoto, S.; Zhang, H.; Aoki, J.; Tanaka, H., Detection of Physiological Activities of G Protein-Coupled Receptor-Acting Pharmaceuticals in Wastewater. Environmental Science & Technology 2015, 49, (3), 1903-1911. 22. Zhang, Y.; Huang, K. L.; Deng, Y. F.; Zhao, Y. P.; Wu, B.; Xu, K.; Ren, H. Q., Evaluation of the Toxic Effects of Municipal Wastewater Effluent on Mice Using Omic Approaches. Environmental Science & Technology 2013, 47, (16), 9470-9477. 23. Snyder, S. A.; Villeneuve, D. L.; Snyder, E. M.; Giesy, J. P., Identification and quantification of estrogen receptor agonists in wastewater effluents. Environmental Science & Technology 2001, 35, (18), 3620-3625. 24. Soto, A. M.; Sonnenschein, C.; Chung, K. L.; Fernandez, M. F.; Olea, N.; Serrano, F. O., The E-Screen Assay as a Tool to Identify Estrogens - an Update on Estrogenic Environmental-Pollutants. Environ Health Persp 1995, 103, 113-122. 25. Lagarde, F.; Beausoleil, C.; Belcher, S. M.; Belzunces, L. P.; Emond, C.; Guerbet, M.; Rousselle, C., Non-monotonic dose-response relationships and endocrine disruptors: a qualitative method of assessment. Environ Health 2015, 14, 13. 26. Huan, J.; Wang, L.; Xing, L.; Qin, X.; Feng, L.; Pan, X.; Zhu, L., Insights into significant pathways and gene interaction networks underlying breast cancer cell line MCF-7 treated with 17beta-estradiol (E2). Gene 2014, 533, (1), 346-55. 27. Ferro, A.; Mestre, T.; Carneiro, P.; Sahumbaiev, I.; Seruca, R.; Sanches, J. M., Blue intensity matters for cell cycle profiling in fluorescence DAPI-stained images. Lab Invest 2017, 97, (5), 615-625. 28. Mandelkow, R.; Gumbel, D.; Ahrend, H.; Kaul, A.; Zimmermann, U.; Burchardt, M.; Stope, M. B., Detection and Quantification of Nuclear Morphology Changes in Apoptotic Cells by Fluorescence Microscopy and Subsequent Analysis of Visualized Fluorescent Signals. Anticancer Res 2017, 37, (5), 2239-2244. 29. Dix, D. J.; Houck, K. A.; Martin, M. T.; Richard, A. M.; Setzer, R. W.; Kavlock, R. J., The ToxCast program for prioritizing toxicity testing of environmental chemicals. Toxicol Sci 2007, 95, (1), 5-12. 30. Tan, L.; Schirmer, K., Cell culture-based biosensing techniques for detecting toxicity in water. Curr Opin Biotech 2017, 45, 59-68. 31. Rato, T. J.; Reis, M. S., Advantage of Using Decorrelated Residuals in Dynamic Principal Component Analysis for Monitoring Large-Scale Systems. Ind Eng Chem Res 2013, 52, (38), 13685-13698. 32. Cummings, B. S.; Wills, L. P.; Schnellmann, R. G., Measurement of cell death in Mammalian cells. Curr Protoc Pharmacol 2012, Chapter 12, Unit12 8.
ACS Paragon Plus Environment
Environmental Science & Technology
497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530
33. Fink, S. L.; Cookson, B. T., Apoptosis, pyroptosis, and necrosis: mechanistic description of dead and dying eukaryotic cells. Infect Immun 2005, 73, (4), 1907-16. 34. Mosmann, T., Rapid Colorimetric Assay for Cellular Growth and Survival Application to Proliferation and Cyto-Toxicity Assays. J Immunol Methods 1983, 65, (1-2), 55-63. 35. Zanella, F.; Lorens, J. B.; Link, W., High content screening: seeing is believing. Trends in biotechnology 2010, 28, (5), 237-45. 36. Antczak, C.; Mahida, J. P.; Bhinder, B.; Calder, P. A.; Djaballah, H., A high-content biosensor-based screen identifies cell-permeable activators and inhibitors of EGFR function: implications in drug discovery. Journal of biomolecular screening 2012, 17, (7), 885-99. 37. Kim, H. S.; Han, S. Y.; Yoo, S. D.; Lee, B. M.; Park, K. L., Potential estrogenic effects of bisphenol-A estimated by in vitro and in vivo combination assays. J Toxicol Sci 2001, 26, (3), 111-8. 38. Teng, C.; Goodwin, B.; Shockley, K.; Xia, M.; Huang, R.; Norris, J.; Merrick, B. A.; Jetten, A. M.; Austin, C. P.; Tice, R. R., Bisphenol A affects androgen receptor function via multiple mechanisms. Chemico-biological interactions 2013, 203, (3), 556-64. 39. Winnicka, K.; Bielawski, K.; Bielawska, A.; Surazynski, A., Antiproliferative activity of derivatives of ouabain, digoxin and proscillaridin A in human MCF-7 and MDA-MB-231 breast cancer cells. Biol Pharm Bull 2008, 31, (6), 1131-40. 40. Litan, A.; Langhans, S. A., Cancer as a channelopathy: ion channels and pumps in tumor development and progression. Frontiers in cellular neuroscience 2015, 9, 86. 41. Sun, X. Y.; Ouyang, J. M., New view in cell death mode: effect of crystal size in renal epithelial cells. Cell Death Dis 2015, 6, e2013. 42. Chiotaki, R.; Polioudaki, H.; Theodoropoulos, P. A., Differential nuclear shape dynamics of invasive and non-invasive breast cancer cells are associated with actin cytoskeleton organization and stability. Biochem Cell Biol 2014, 92, (4), 287-295. 43. Tobin, L. A.; Robert, C.; Nagaria, P.; Chumsri, S.; Twaddell, W.; Ioffe, O. B.; Greco, G. E.; Brodie, A. H.; Tomkinson, A. E.; Rassool, F. V., Targeting abnormal DNA repair in therapy-resistant breast cancers. Molecular cancer research : MCR 2012, 10, (1), 96-107.
531 532 533 534 535 536
ACS Paragon Plus Environment
Page 20 of 27
Page 21 of 27
Environmental Science & Technology
537 538
Figure 1. Phenotypic effects of single compounds on MCF-7 cells. 13 multiple phenotypic
539
parameters were normalized to the control for cells treated with thirty compounds at varying
540
concentration. The fold change values are shown by numbers on the bar and the color scale
541
shows increase (red) and decrease (blue), per dose from 10-12 M to 10-6 M within each grid.
542 543 544 545 546 547 548 549
ACS Paragon Plus Environment
Environmental Science & Technology
550 551
Figure 2. Phenotypic effects of chemical mixtures on MCF-7 cells. Confocal images of
552
MCF-7 cells exposed to chemical mixture (A) and a phenotypic analysis using 13 parameters
553
(B). 13 multiple phenotypic parameters were normalized by control and the fold change values
554
are shown by numbers on the bar and the color scale shows increase (red) and decrease (blue),
555
per dose from 10-12 M to 10-6 M within each grid
556 557 558 559 560
ACS Paragon Plus Environment
Page 22 of 27
Page 23 of 27
Environmental Science & Technology
561 562
Figure 3. Phenotypic analysis of MCF-7 cells after exposure to whole water
563
samples. Confocal images of MCF-7 cells exposed to wastewater and river water (A)
564
and phenotypic analysis using 13 parameters (B). The arrows indicate (1) control cells,
565
(2) condensed cells, (3) scattering cells, (4) echinoid spike cells, and (5) enlarged nuclei.
566 567 568 569 570
ACS Paragon Plus Environment
Environmental Science & Technology
571 572
Figure 4. Principal components analysis (PCA) plot of phenotypic variation in cells
573
exposed to single compounds (A), chemical mixtures (B), and whole water(C).
574
W1-Inf, W1-Eff, W3-Inf, T2, T8, and T9 (underlined) were selected for non-target
575
chemical analysis.
ACS Paragon Plus Environment
Page 24 of 27
Page 25 of 27
Environmental Science & Technology
576 577
Figure 5. Comparison of the phenotypic analysis (A) and conventional cell viability
578
analyses (B) for whole water toxicity evaluation. * P