Received: 28 February 2022
DOI: 10.1111/cts.13282  

| Revised: 21 March 2022 | Accepted: 30 March 2022

ARTICLE

Discovery of preventive drugs for cisplatin-­induced acutekidney injury using big data analysis
Masaya Kanda1,2 | Mitsuhiro Goda1,2,3| Akiko Maegawa1 | Toshihiko Yoshioka1,2
Ami Yoshida1 | Koji Miyata1 | Fuka Aizawa1,2 | Takahiro Niimura1,3|
4
2
2
Hirofumi Hamano | Naoto Okada | Takumi Sakurada | Masayuki Chuma5
|
3
6
3
1,4
Kenta Yagi | Yuki Izawa-­Ishizawa | Hiroaki Yanagawa | Yoshito Zamami|
1,2,3
Keisuke Ishizawa
1

Department of Clinical Pharmacology
and Therapeutics, Tokushima
University Graduate School of
Biomedical Sciences, Tokushima, Japan2

Department of Pharmacy, Tokushima
University Hospital, Tokushima, Japan

3

Clinical Research Center for
Developmental Therapeutics,
Tokushima University Hospital,
Tokushima, Japan

4

Department of Pharmacy, Okayama
University Hospital, Okayama, Japan

5

Department of Pharmacy, Asahikawa
Medical University Hospital, Hokkaido,
Japan

6

Department of Pharmacology,
Tokushima University Graduate School of
Biomedical Sciences, Tokushima, Japan
Correspondence
Mitsuhiro Goda, Departmentof Clinical Pharmacology andTherapeutics, Tokushima University
Graduate School of Biomedical
Sciences, 3-­18-­15 Kuramoto, Tokushima
770-­8503, Japan.
Email: mgoda@tokushima-­u.ac.jp
Funding information
This work was supported by the Japan
Society for the Promotion of Science(JSPS) KAKENHI (grant numbers
20 K07132 and 20H05799). The funders
had no involvement in the study design,|

Abstract
Cisplatin is effective against many types of carcinoma. However, a high rate ofrenal damage is a clinical problem. Thus, there is a need to establish a method
to prevent it. Although various compounds have been reported to be effective
against cisplatin-­induced renal injury, there are no examples of their clinicalapplication. Therefore, we attempted to search for prophylactic agents with ahigh potential for clinical application. We used Cascade Eye to identify genesthat are altered during cisplatin-­induced renal injury, Library of Integrated
Network-­based Cellular Signatures (LINCS) to identify drugs that inhibitchanges in gene expression, and a large database of spontaneous adverse drug
reaction reports to identify drugs that could prevent cisplatin-­induced kidney
injury in clinical practice. In total, 10 candidate drugs were identified. Using
the US Food and Drug Administration (FDA) Adverse Event Reporting System(FAERS), we identified drugs that reduce cisplatin-­induced kidney injury.
Fenofibrate was selected as a candidate drug to prevent cisplatin-­induced kidney injury based on the FAERS analysis. A model was used to evaluate theefficacy of fenofibrate against cisplatin-­induced renal injury. Studies using
HK2 cells and mouse models showed that fenofibrate significantly inhibited
cisplatin-­induced renal injury but did not inhibit the antitumor effect of cisplatin. Fenofibrate is a candidate prophylactic drug with high clinical applicability for cisplatin-­induced renal injury. Analysis of data from multiple big
databases will improve the search for novel prophylactic drugs with high clinical applicability. For the practical application of these findings, evaluation inprospective controlled trials is necessary.

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any
medium, provided the original work is properly cited and is not used for commercial purposes.
© 2022 The Authors. Clinical and Translational Science published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.
1664

	﻿
| www.cts-journal.com

Clin Transl Sci. 2022;15:1664–1675.

DISCOVERY OF PREVENTIVE DRUGS FOR CDDP-­INDUCED AKI

collection, analysis, and interpretationof data; preparation of the report; or thedecision to submit the manuscript for
publication.

  | 1665

Study Highlights
WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
Current coping strategies in clinical practice do not completely prevent cisplatin-­induced renal injury, warranting development of supportive care.
WHAT QUESTION DID THIS STUDY ADDRESS?
Many drugs and compounds have been reported to be effective against cisplatin-­induced renal injury in basic in vitro and in vivo studies, but none have been
applied clinically. In this study, we used medical big data to identify candidate
prophylactic drugs with high potential for clinical application.
WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
This study used an artificial intelligence tool called Cascade Eye and two large
medical information databases, Library of Integrated Network-­based Cellular
Signatures (LINCS) and US Food and Drug Administration Adverse Event
Reporting System (FAERS), to identify candidate drugs that reduce cisplatin-­induced kidney injury and found that the candidate drug fenofibrate has the potential to prevent cisplatin-­induced kidney injury.
HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR
TRANSLATIONAL SCIENCE?
The developed methods can be applied to the development of prophylactic drugs
against various adverse drug reactions and will have an impact on future clinicalpharmacology and translational research.

I N T RO DU CT ION
Cisplatin is a platinum-­based anticancer drug used in
the chemotherapy of several malignant solid tumors,
including lung, bladder, and head and neck cancer.1 It
binds to purine bases in intracellular DNA and forms
cross-­links to inhibit DNA replication and transcription, thereby exerting an antitumor effect. However,cisplatin causes numerous side effects, such as acutekidney injury, hearing impairment, nausea and vomiting, and myelosuppression. In particular, acute kidney
injury occurs in ~30% of patients treated with cisplatin,2restricting further cisplatin administration. Acute renal
injury may lead to chronic tubulointerstitial fibrosis or
irreversible chronic tubulopathy, possibly resulting inchronic renal failure.3 Additionally, hypomagnesemia isfrequently observed during cisplatin administration because of increased renal excretion and gastrointestinal
toxicity.4 Although various platinum-­based drugs havebeen developed to reduce side effects, cisplatin remains
widely used in clinical practice. To prevent cisplatin-­induced nephrotoxicity, the administration of supplemental fluids such as saline (more than 3 L/day) anddiuretic medication is recommended.4 However, renal
injury cannot be completely prevented, and further development of supportive care is required. Although basic
experiments have identified a number of candidates fortreating cisplatin-­induced renal injury, none have beencommercialized.5 In addition to pharmacodynamic
safety, the drug must be safe for use in combination

with cisplatin or other anticancer drugs used with cisplatin without affecting efficacy. Therefore, a drug thatis determined to be effective in basic experiments may
not be useful in clinical practice. Reverse translational
research can be used to search for effective drugs in theclinical setting and verify their efficacy and mechanismof action in basic experiments.
Drug repositioning, a method of discovering new effects in an existing approved drug and developing that
drug as a treatment for a different disease, was used tofind a preventive medication for cisplatin-­induced kidney
injury. As information on safety and pharmacokinetics inhumans has been accumulated, repositioned drugs canbe rapidly applied clinically. Even when basic research
has shown some degree of safety and efficacy, ~90% of
drugs are abandoned for further analysis at the clinical
trial stage.6 Thus, drug development is a time-­consuming
and labor-­intensive process. Drug repositioning is gaining worldwide attention to resolve this problem. The
number of papers related to drug repositioning has increased considerably (~160 times) over the past 20 years
and has tripled since 2016. Large-­scale medical information databases have been constructed to provide information on changes in gene expression and adverse drug
reactions, making it possible to reuse drugs. We used the
US Food and Drug Administration (FDA) Adverse Event
Reporting System (FAERS) to identify prophylactic drugs
against cisplatin-­induced renal injury among existing approved drugs. FAERS collects and publishes voluntary
reports of adverse events reported worldwide. With over

1666

|   

14 million reports, it is the largest database of its kind.
Additionally, the Library of Integrated Network-­based
Cellular Signatures (LINCS) program is a drug discovery tool that simulates the changes in the expression of~20,000 genes in response to chemical substances using
human cell lines. It has been applied to research on thedevelopment of novel therapeutics.7,8 Specifically, it has
been used in many studies, including our own, to identify drugs that can prevent adverse events of high-­risk
drugs.9–­11 However, the analysis of big data alone is insufficient as the evidence of efficacy. In this study, we used
big data analysis to identify candidate drugs to prevent
cisplatin-­induced renal injury and examined their efficacy and safety in cells and animals.

M AT E R I A L S AN D MET H ODS
Data mining-­based selection to identify a
network of genes involved in preventing
kidney damage
Cascade Eye, developed by FRONTEO Inc., was used to
extract a list of genes with altered expression upon renal
injury. Cascade Eye is a natural language processing-­
based artificial intelligence (AI) tool that can extract all
genes related to a particular disease or condition that appears in published papers. It can also identify genes thatare causative or responsive to the disease or condition.
Cascade Eye identified 20 genes that were responsive tocisplatin-­induced renal injury (Table S1).

Selection of prophylactic drug candidates
using the National Institutes of Healthgene expression database
In Cascade Eye, we identified 20 genes that respondto cisplatin-­induced renal injury and further analyzed
these 20 genes with LINCS L1000CDS2. Among these,
genes associated with the promotion of cisplatin-­induced acute kidney injury were classified as “upregulated genes,” and genes associated with the suppressionof cisplatin-­induced acute kidney injury were classified
as “downregulated genes” based on a literature search.
These genes were entered into LINCS L1000CDS2, aweb-­based search application. The top 50 compounds
causing gene expression opposite to the entered patternwere searched in the order of the similarity score of theexpression pattern. Among the top 50 compounds in the
search results, compounds that were approved as drugsby the FDA were selected as candidate prophylactic
drugs.

KANDA et al.

Effect of concomitant drugs using FAERS
From January 2007 to March 2017, there were 7,738,415
spontaneous adverse event reports that were submitted
to the FAERS, which were downloaded from the FDA
website (https://www.fda.gov/Drugs/​Guida​nceCo​mplia​
nceRe​gulat​oryIn​forma​tion/Surve​illan​ce/Adver​seDru​g​Effe​cts/ucm08​2193.htm; data accessed on September2020).12 Duplicate data were excluded in accordance with
the FDA recommendations, and the remaining 6,994,117
reports were used for analysis. MySQL software (version 5.7.21) was used to build a database that integrated
the FAERS data, and R version 3.2.1 (R Foundation for
Statistical Computing, Vienna, Austria) was used for statistical analyses.
Adverse events were designated according to the
47 extracted terms from the “acute renal failure (SMQ
20000003)” group, which is based on the Medical
Dictionary for Regulatory Activities/J version 23.1,
International Glossary of Pharmaceutical Terms ofInternational Council for Harmonization of TechnicalRequirements for Pharmaceuticals for Human Use(Table S1).
The risk of adverse events was assessed using the reporting odds ratio (ROR) and 95% confidence interval(CI). Patients administered with cisplatin were classified into four groups: patients who (1) used drug A andreported acute renal failure, (2) used drug A and did notreport acute renal failure, (3) did not use drug A and reported acute renal failure, and (4) did not use drug A anddid not report acute renal failure. Based on the following
equation, the ROR and 95% CI were calculated.
ROR =
(

AD
BC
√

95 % CI = exp ln ROR ± 1.96

)
1
1
1
1
+ + +
A B C D

All tests were two-­tailed, and results with p values < 0.05
were considered statistically significant.

Animal model of cisplatin-­induced
nephrotoxicity
All animal experiments were performed in accordance with the ARRIVE guidelines. All experimental procedures were performed in accordance withthe guidelines of the Animal Research Committee ofTokushima University Graduate School, and the protocol was approved by the Institutional Review Boardof Tokushima University Graduate School for Animal

DISCOVERY OF PREVENTIVE DRUGS FOR CDDP-­INDUCED AKI

Protection (Permit Number: T30-­85). Nine-­to-­10-­week-­
old C57BL/6J male mice (weighing 24–­27 g) werepurchased from Nippon CLEA (Tokyo, Japan) andmaintained with ad libitum access to water and food(type NMF; Oriental Yeast, Tokyo, Japan). The relative
humidity in the breeding room was 50 ± 10%, and theroom temperature was 26 ± 1°C, with a 12-­h light/darkcycle (lights on at 8:00, lights off at 20:00). The mousemodel of cisplatin-­induced renal injury was generated
following a previously described method.13
The mice were randomly divided into eight groups(n = 7–­9 per group): vehicle-­injected, cisplatin-­injected,
and fenofibrate (30, 100, and 300 mg/kg) or bezafibrate (30,100, and 300 mg/kg) administered to the cisplatin-­injectedgroup. The mice were intraperitoneally injected with cisplatin (15 mg/kg) or vehicle (saline). Thirty minutes before
cisplatin injection, the mice were administered the prophylactic drug candidates or vehicle (0.1% tween20 aqueous solution); 72 h after cisplatin injection, experimental
mice were anesthetized, and samples (serum, urine, andkidney) were collected for subsequent analysis. Anesthesia
was induced by the inhalation of isoflurane under a 4% diluted vaporizer setting (vaporized in oxygen 1 L/min) andmaintained with isoflurane under a 2% vaporizer setting.
The isoflurane was delivered via a small face mask. The
doses were based on those used in previous animal studiesof these candidates as dyslipidemia agents.14–­17

Determination of blood and urine
creatinine and blood urea nitrogen levels
The levels of blood urea nitrogen (BUN), serum creatinine(serum Cr), and urine creatinine (urine Cr) in the serumand urine samples collected 72 h after cisplatin administration were determined by Oriental Yeast Industries (Shiga,
Japan). Creatinine clearance (Ccr) was calculated as follows:
Ccr (ml∕min∕kg) = urine volume (ml∕min∕kg)
× urine Cr concentration (mg∕L)∕ serum Cr concentration (mg∕L)

Real-­time polymerase chain reaction usingkidney tissues from mice with cisplatin-­induced kidney injury
The kidneys were collected from mice with cisplatin-­induced kidney injury. RNA was extracted from the kidney samples using an RNA extraction solution (NIPPON
GENE, Tokyo, Japan) according to the manufacturer’s
instructions. cDNA was reverse-­transcribed using thePrimeScript RT Reagent kit (Takara Bio, Shiga, Japan)
and a PCR Thermal Cycler Dice (Takara Bio). The cDNA  

| 1667from each sample was mixed with forward and reverse
primers and THUNDERBIRD SYBR qPCR Mix (Toyobo,
Osaka, Japan); polymerase chain reaction (PCR) was performed using an Applied Biosystems StepOnePlus system(Applied Biosystems, Foster City, CA). Fold changes ingene expression relative to those of the control group were
evaluated using mouse Gapdh as an internal standard.
The primer sets used for PCR are presented in Table S1.
All experiments were performed in triplicate. All data
were analyzed using CFX Manager software (Bio-­Rad
Laboratories, Hercules, CA).18

Histological analysis
Renal tubular injury was assessed as previously described.19 Kidney samples were fixed with 4% paraformaldehyde and embedded in paraffin. The samples were cut
into 4-­μm sections, which were stained with hematoxylin
and eosin. Tubular damage was scored blindly by three ormore researchers trained in tissue assessment, other thanthe experimenter, according to the percentage of damage (tubular necrosis, brush border loss, cast formation,
tubular dilation, and tubular degeneration), as follows: 0,
normal; 1, <25%; 2, 25–­50%; 3, 50–­75%; and 4, >75%. Ten
random microscopic fields per kidney section were used
for quantification using the BX53 microscope (Olympus,
Tokyo, Japan).

Cell culture
We used HK2 cells (ATCC CRL-­2190; human proximal tubule cell: obtained from American Type Culture
Collection, Manassas, VA) to investigate the effect offenofibrate on cisplatin-­induced cell death. To test the effect of fenofibrate on the anticancer effect of cisplatin, weused mouse Lewis lung carcinoma (LLC) cells and Colon
26 murine colon carcinoma cells. The cells were maintained and subcultured in Dulbecco’s Modified Eagle’s
Medium (DMEM) containing 10% fetal bovine serum(FBS), 100 U/ml penicillin, and 100 μg/ml streptomycin in
an atmosphere of 95% air/5% CO2 at 37°C, according to
the culture protocol. The cells were passaged at 80% confluence, and experiments were performed using cells withpassages between 5 and 15.

Cell viability assay
Cell viability was assessed using a Cell Counting Kit-­8(Dojindo Laboratories, Kumamoto, Japan) according to
the manufacturer’s instructions. The cells were seeded

1668

|   

into 96-­well plates at a concentration of 5 × 104 cells perwell and incubated at 37°C for 24 h. Then, they were cultured in media with or without 50 μM cisplatin for 24 h.
Fenofibrate (1, 10, and 100 μM) or bezafibrate (1, 10, and100 μM) was used for treatment with or without cisplatin administration. Additionally, 2 μM PPARα inhibitor
GW6471 was used. Fenofibrate, bezafibrate, and GW6471
were dissolved in dimethylsulfoxide (DMSO) and adjusted
to a final concentration of 0.2% DMSO. Cell ­viability wasassessed by measuring the absorbance of WST-­8 formazanat 450 nm using a plate reader (Model680 microplate
reader; Bio-­Rad Laboratories).

Statistical analysis
To compare three or more groups, one-­way analysis ofvariance (ANOVA) was performed. Tukey’s test was performed as a post hoc analysis. R version 3.2.1 for Windows
was used for statistical analyses. Results with a two-­tailed
p < 0.05 were considered statistically significant.

RES ULT S
Identification of agents capable ofpreventing cisplatin-­induced kidney injury
First, we extracted genes whose expression was altered bycisplatin administration. Using an AI tool called Cascade
Eye, we identified 20 genes whose expression was alteredduring cisplatin-­induced kidney injury. Among these, weclassified seven associated with the promotion of acutekidney injury as “upregulated genes” and 13 associatedwith the suppression of acute kidney injury as “downregulated genes” by literature search (Table S1).
We then used the L1000CDS2 search engine to identify
10 approved drugs that counteract the altered gene expression in cisplatin (Table 1).

FAERS analysis results
We used FAERS to examine the effects of these 10 drugs
on cisplatin-­induced renal injury. We included 28,755 patients treated with cisplatin in the analysis after excluding
duplicate data from 6,994,117 reports. The RORs for fenofibrate, diltiazem, metoprolol, vorinostat, and cyclosporine
were 0.39, 0.93, 1.02, 1.10, and 1.90, respectively (Table 2).
Of the 10 drugs extracted by LINCS, only the five drugs
mentioned above had reports of concomitant use of cisplatin. Based on these results, fenofibrate was identified as anovel candidate for prophylaxis.

KANDA et al.

TABLE 1Drug candidate selection by LINCS analysis

Cyclosporin A

Menadione

Diflorasone diacetate

Metoprolol

Diltiazem

Niclosamide

Fenofibrate

Vinpocetine

Gemcitabine

Vorinostat

Note: We identified compounds that promote the expression of suppressor
genes and inhibit the expression of accelerator genes in cisplatin-­induced
renal injury by LINCS analysis. Ten approved drugs were extracted.
Abbreviation: LINCS, Library of Integrated Network-­based Cellular
Signatures.

Effects of fenofibrate or bezafibrate on
cisplatin-­induced kidney injury in mice
The effect of fenofibrate or bezafibrate on cisplatin-­induced
renal injury was investigated in mice. In cisplatin-­treatedmice, body weight was lower than that in solvent-­treated
mice; however, kidney weight was unchanged (Table 3).
Cisplatin-­treated mice showed renal damage with increased mRNA expression of Kim-­1 and Lcn2, markers
of renal tubular damage, increased plasma BUN, andsignificantly decreased creatinine clearance comparedwith the solvent-­treated group (Table 3, Figure 1a,b). The
combination of cisplatin and fenofibrate significantly
ameliorated the cisplatin-­induced renal impairment ina dose-­dependent manner (Table 1, Figure 1a,b). In contrast, the combination with bezafibrate did not improve
cisplatin-­induced renal injury (Figure 1a,b).

Histological evaluation
Histological changes in renal tubules of mice were observed by hematoxylin and eosin staining. In cisplatin-­treated mice, the degeneration and destruction of renal
tissue were observed, including loss of nuclei, hollowing
out of proximal tubular cells, and dilatation of tubules.
Mice treated with fenofibrate exhibited less tubular dilation and necrosis of tubular cells than those treatedwith cisplatin alone (Figure 1c). Tubular dysfunction in
kidney sections was scored blindly from 0 to 4 by several
researchers. The fenofibrate combination group scoredsignificantly higher than the cisplatin alone group in adose-­dependent manner (Figure 1d).

Influence of inflammatory cytokines
Quantitative real-­time PCR confirmed that the mRNA expression levels of IL-­1β, IL-­6, and TNF-­α in the kidneys
were increased by cisplatin treatment; however, they wereDISCOVERY OF PREVENTIVE DRUGS FOR CDDP-­INDUCED AKI

T A B L E 2 Effect of prophylactic drugcandidates on the occurrence of cisplatin-­induced ARF using the FAERS data
analysis  | 1669Drug

ARF (%) without
the drug

ARF (%)
with thedrug

ROR (95% CI)

p ValueFenofibrate

8.81 (2324/26379)

3.45 (2/58)

0.39 (0.05–­1.48)

0.236

Diltiazem

7.54 (2009/26662)

6.98 (6/86)

0.93 (0.33–­2.10)

1Metoprolol

7.53 (1994/26474)

7.66 (21/274)

1.02 (0.33–­2.10)

0.909

Vorinostat

8.80 (2320/26375)

9.68 (6/62)

1.10 (0.39–­2.54)

0.822

Cyclosporine

8.78 (2315/26371)

16.67 (11/66)

1.90 (0.90–­3.63)

0.056

Note: Among the 10 drugs extracted by the LINCS analysis, there were five drugs for which FAERS
analysis was possible. Among these, fenofibrate had an ROR <1 in the FAERS analysis, and the numberof reports of cisplatin-­induced renal injury was significantly lower than reports without fenofibrate.
Statistical analysis was conducted using Fisher’s exact test.
Abbreviations: ARF, acute renal failure; CI, confidence interval; FAERS, US Food and Drug
Administration Adverse Event Reporting System; LINCS, Library of Integrated Network-­based Cellular
Signatures; ROR, reporting odds ratio.

significantly lower in the kidneys of the cisplatin andfenofibrate combination group than in those of the cisplatin group (Figure 2).

Involvement of PPARα in the inhibitory
effect of fenofibrate on cisplatin-­induced
cytotoxicity
The effect of fenofibrate and bezafibrate on cisplatin-­induced cell death was investigated using HK2 cells.
Twenty-­four hour after cisplatin (50 μM) treatment, thecell viability of HK2 cells was significantly lower than thatin the vehicle-­treated group. A combination of fenofibrate(1, 10, and 100 μM) significantly increased the cell viability
in a dose-­dependent manner compared with the cisplatin-­treated group (Figure 3a). In contrast, the combination of
bezafibrate (1, 10, and 100 μM) exhibited no change in cell
viability (Figure 3b). We further investigated the involvement of PPARα in the inhibitory effect of fenofibrate on
cisplatin-­induced cytotoxicity; the addition of GW6471, a
PPARα inhibitor, suppressed the improvement of cell viability by fenofibrate (Figure 3c).

Effect of fenofibrate on the anticancer
action of cisplatin
The effect of fenofibrate on the anticancer effect of cisplatin was examined using LLC cells, a mouse lung cancer
cell line, and colon-­26 cells, a mouse colon cancer cellline. Twenty-­four h after cisplatin (50 μM) treatment, thecell viability of LLC and colon-­26 cells was significantly
lower than that in the vehicle-­treated group. The combined use of fenofibrate (100 μM) did not change the cell
viability as compared with the cisplatin-­treated group(Figure 4).

DISC USSION
In this study, we searched for candidates for drugs withhigh clinical potential to reduce cisplatin-­induced renal
injury by analyzing using an AI tool called Cascade Eyeand two large medical information databases, LINCS andFAERS. Furthermore, basic research using animal models and cells suggest that fenofibrate, not bezafibrate, is apotential prophylactic drug for the prevention of cisplatin-­induced renal injury.
Adverse effects of cisplatin, including renal impairment, are a major clinical challenge as they interfere with the continuation of treatment. Using an AI
tool called Cascade Eye, we extracted a group of genesthat have been reported to be involved in the mechanism of cisplatin-­induced kidney injury development.
Furthermore, using LINCS, we searched for drugs thatcan reverse the gene expression changes induced bycisplatin and extracted 10 existing approved drugs. We
also used FAERS to compare the reported frequencyof cisplatin-­induced kidney injury in patients treatedwith cisplatin with and without the candidate drugs.
Fenofibrate achieved an ROR < 1, suggesting that it reduces the incidence of cisplatin-­induced renal injury(Table 2). Although fenofibrate is used as a treatment
for dyslipidemia, in the FAERS database, we searched
for statins that treat dyslipidemia as well as a similar drug, bezafibrate. Fenofibrate had the smallest reported odds ratio for cisplatin-­induced kidney injury(data not shown). A number of other drugs had odds
ratios >1, indicating that dyslipidemia drugs do not
uniformly reduce the risk of developing renal injury.
Therefore, the improvement of dyslipidemia may notcontribute to the improvement of renal impairment by
cisplatin. Furthermore, analysis of rhabdomyolysis, aknown side effect of fenofibrate, showed that the ROR
for rhabdomyolysis was smaller than 1 (data not shown)|   

22.8 ± 4.0*
23.1 ± 5.8*
26.4 ± 8.8*
8.5 ± 1.0**
22.2 ± 6.1*
35.6 ± 6.2
86.4 ± 25.9†
2.7 ± 0.3

Note: Data are presented as mean ± SEM. p < 0.05 versus vehicle mice, *p < 0.05 and **p < 0.01 versus cisplatin mice. n = 4–­9 in each group.

Ccr, ml/min/kg

Abbreviations: Beza, bezafibrate; BUN, blood urea nitrogen; Ccr, creatinine clearance; Feno, fenofibrate.

BUN, mg/dl

2.2 ± 0.4

19.2 ± 2.3

11.59 ± 1.82

Urine volume, ml

ratio

1.66 ± 0.15

Kidney weight/bodyweight, mg/g

BUN Ccr

6.86 ± 0.38

Kidney weight, mg−1

24.5 ± 0.5

167.5 ± 8.4

Post body weight, g

24.4 ± 0.5
Initial body weight, g†

2.1 ± 0.3

3.94 ± 0.43

83.5 ± 14.4
104.0 ± 28.7

4.95 ± 0.59*
4.29 ± 0.51*

79.2 ± 14.8
43.3 ± 1.6**

5.53 ± 0.57**
3.75 ± 0.72

66.4 ± 5.3*
80.9 ± 5.8

2.47 ± 0.30
2.14 ± 0.36†

132.4 ± 13.2†
23.4 ± 1.5

8.67 ± 0.53
9.80 ± 1.53

19.3 ± 1.0

0.69 ± 0.10
0.89 ± 0.13
0.96 ± 0.12
0.81 ± 0.14
0.63 ± 0.08
0.43 ± 0.05
0.74 ± 0.11†
1.52 ± 0.20
1.67 ± 0.17

7.30 ± 0.14
7.73 ± 0.28
6.98 ± 0.17
7.45 ± 0.37
7.45 ± 0.23
7.54 ± 0.32
7.41 ± 0.49
7.11 ± 0.28
6.44 ± 0.73

21.3 ± 0.5

155.6 ± 4.8
164.3 ± 5.1

21.4 ± 0.8
22.2 ± 0.8

155.1 ± 6.0
164.3 ± 6.4

22.1 ± 0.8
20.9 ± 0.4

155.6 ± 3.9
154.4 ± 5.8

20.5 ± 0.7
18.9 ± 0.2†

140.0 ± 10.
163.8 ± 6.9

23.1 ± 0.8
26.6 ± 0.5

170.8 ± 17.2

26.1 ± 0.6
25.4 ± 0.5
25.8 ± 0.5
26.8 ± 0.5
26.7 ± 0.5
26.3 ± 0.6
23.9 ± 0.5
24.4 ± 0.7
27.8 ± 0.5

Feno(300 mg/kg)

Beza(300 mg/kg)

Cisplatin

Cisplatin + Feno
(30 mg/kg)

Cisplatin + Feno(100 mg/kg)

Cisplatin + Feno(300 mg/kg)

Cisplatin + Beza
(30 mg/kg)

Cisplatin + Beza
(100 mg/kg)

Cisplatin + Beza
(300 mg/kg)

KANDA et al.

VehicleBody weight, kidney weight, and renal function in vehicle-­treated mice and cisplatin-­treated mice with or without fenofibrate or bezafibrate
TABLE 31670

in patients who used fenofibrate in combination withcisplatin compared to those who used fenofibrate alone.
Our data suggest that the combination of cisplatin andfenofibrate may not increase side effects. These results
suggest that fenofibrate has a high potential for clinical application as a prophylactic agent against cisplatin-­induced renal injury. It has been reported that PPARα
stimulators and fibrates are effective against cisplatin-­induced renal injury in basic in vivo and in vitro studies (PMID: 26536032 and 27193727). However, in vivo
studies using mouse models of cisplatin-­induced kidney
injury have not compared fenofibrate and bezafibrate,
which are fibrates frequently used in clinical practice,and their mechanisms of action are controversial. As
fenofibrate was extracted as a candidate drug throughbig data analysis, we also examined the effect of bezafibrate, a known fibrate drug. The doses of fenofibrate
and bezafibrate were determined based on those used inprevious studies to treat mice.20–­23 In addition to BUN
and Ccr, the expression levels of Kim-­1 and Lcn-­2 in thekidneys were measured and evaluated histologically as
indicators of renal damage. Cisplatin-­induced renal injury is assumed to be caused by proximal tubular cell injury, and just as BUN and Ccr values reflect GFR, Kim-­1,
and Lcn-­2 in the kidneys are considered to be suitableindicators of renal injury. In animal experiments, Kim-­1and Lcn-­2 in the kidneys are significantly increased in
cisplatin-­induced kidney injury models.24,25 IL-­6, IL-­1β, and TNF-­α are pro-­inflammatory cytokines; TNF-­αplays an important role in the progression of cisplatin-­induced renal injury and is involved in the release ofother pro-­inflammatory cytokines. Previous studies
have shown that the release of TNF-­α in renal cells, but
not immune cells, is involved in the worsening of renal
injury.26,27
Cisplatin-­induced renal injury occurs when cisplatin
is taken up by proximal tubular cells in the kidney via
the high-­affinity copper transporter 1 and organic cationtransporter (OCT2) on the basement membrane side of thecell.4 Because fenofibrate has been reported to downregulate the renal OCT2 transporter via a PPARα-­independent
pathway,15 renal platinum levels were measured to investigate the effect of fenofibrate on cisplatin accumulationin the kidneys. Consequently, there was no change in theamount of platinum in the kidneys, whole blood, or urine(data not shown).
Cisplatin-­induced renal injury is believed to be causedby cisplatin-­induced oxidative stress and DNA damage,which inhibit the nuclear translocation of PPARα, resulting in ATP depletion, lipotoxicity, and tubular cell damage.
The beta-­oxidation of free fatty acids is a major energy-­
producing pathway in the kidneys and is inhibited in acuterenal failure. The inactivation of PPARα and decreased

DISCOVERY OF PREVENTIVE DRUGS FOR CDDP-­INDUCED AKI

  

(a)

(b)

(c)

(d)

| 1671F I G U R E 1 Effect of fenofibrate on cisplatin-­induced nephrotoxicity. (a, b) The mRNA expression levels of kidney injury markers Kim-­1(a) and Lcn-­2 (b) in the kidneys of mice in each group. (c) Representative hematoxylin and eosin staining (HE) of the kidney section of thecontrol mice, cisplatin-­injected mice with vehicle or fenofibrate. The scale bar indicates 100 μm. (d) Quantitative analysis of renal damage
scores. Values are expressed as mean ± SEM. Cis, cisplatin; Feno, fenofibrate. †p < 0.05 versus vehicle mice, *p < 0.01 versus cisplatin mice,n = 4–­9 in each groupexpression of PPARγ are considered the main causes of
the inhibition of fatty acid oxidation.17 Additionally, aPPARα agonist (WY-­14643) has been reported to inhibit
cisplatin-­induced renal injury via PPARα.14 Based onthese reports, we conducted cell experiments to investigate whether PPARα is involved in the mechanism of theinhibitory effect of fenofibrate on cisplatin-­induced renal
injury. The results showed that fenofibrate ameliorated
cisplatin-­induced cytotoxicity; however, the addition of
GW6471, a PPARα inhibitor, tended to decrease cell viability. In addition, pretreatment with fenofibrate had thesame effect as simultaneous treatment (data not shown).
Therefore, the mechanism of the inhibition of cisplatin-­induced renal injury by fenofibrate may partly involve
the activation of PPARα, which has been reported to haveanti-­inflammatory effects.28
The difference in the effects of fenofibrate and bezafibrate on cisplatin-­induced renal injury may be partly
related to the difference in the affinity of fenofibrate andbezafibrate for PPARα. Reportedly, the half-­maximal effective concentration (EC50) values of fenofibrate andbezafibrate for human PPARα are 30 and 50 μM, respectively.29 However, cell experiment results suggest thatthe activation of PPARα is only part of the mechanismof the nephroprotective action of fenofibrate. Anotherpossible pathway of fenofibrate is the inhibition of oxidative stress.30 Previous studies using oxidative stress-­
induced ischemic kidney injury models have reported
that PPARα agonists reduce the levels of BUN, Ccr,
inflammatory cytokines, and serum creatinine, which
are exacerbated in mouse models of ischemic kidney
injury.31–­33 Fenofibrate has been reported to have antitumor effects in numerous cell and animal experiments alone.16,34 The present cell experiments suggestthat fenofibrate does not interfere with the antitumor
effect of cisplatin. Previous reports have shown that
fenofibrate has a direct antitumor effect in vitro (PMID:
29760790) and an inhibitory effect on tumor growth

1672

|   

(a)

KANDA et al.

(b)

(c)

F I G U R E 2 Effect of fenofibrate on inflammatory cytokine expression in the kidneys. The mRNA expression levels of inflammatory
cytokines IL-­1β (a), IL-­6 (b), and TNF-­α (c) in the kidneys of mice in each group. Values are expressed as mean ± SEM. Cis, cisplatin; Feno,
fenofibrate. †p < 0.05 versus vehicle mice, *p < 0.01 versus cisplatin mice, n = 4–­9 in each groupby inhibiting angiogenesis in vivo (PMID: 18199835).
Therefore, it is suggested that in patients with cancer,
fenofibrate itself is unlikely to interfere with the therapeutic effect of cisplatin.
There are certain limitations to this study. First, thegene expression recorded in LINCS is based on cell line
data. Therefore, rather than using LINCS alone to determine candidate drugs, FAERS was used to evaluate
the efficacy of LINCS on the reported rate of cisplatin-­induced renal injury. In fact, FAERS analysis results
showed that none of the existing approved drugs extracted from the LINCS except fenofibrate were effective
against cisplatin-­induced renal injury events, and thesewere subsequently excluded as candidate drugs. Second,although FAERS is a database for reporting spontaneousadverse events, it does not include all patients who haveused cisplatin or concomitant medications because patients who have not experienced adverse events are notregistered. Additionally, some patients who experienced
adverse events were not reported. Therefore, the reported
incidence of renal injury owing to cisplatin calculated
in the FAERS analysis may be different from the actual

incidence in clinical practice. Third, the FAERS analysis
does not consider the effect of confounding factors; theROR is calculated based on the number of reports on theuse of concomitant medications but is not adjusted forage, gender, or medical history. Moreover, medical history could not be evaluated because it was not listed in
FAERS. Because of these limitations, the results of the
FAERS review may not accurately reflect the actual patients. However, considering the difficulty of collecting
case reports of inconsistent adverse effects, such as renal
impairment caused by cisplatin, FAERS analysis results,
which contains a large amount of data from actual patients, may be useful in investigating actual clinical practice. Therefore, further evidence, such as multicenter
randomized clinical trials, is needed to determine
whether fenofibrate is effective in preventing renal injury
events in patients receiving cisplatin.
Furthermore, it has recently been reported that the adverse effect of fenofibrate, an elevation in serum creatinine
tested at the time of diagnosis of rhabdomyolysis, is transient and reversible. Fenofibrate has also been reported toinhibit proteinuria and may have a renoprotective effectDISCOVERY OF PREVENTIVE DRUGS FOR CDDP-­INDUCED AKI

(a)

  

| 1673(b)(c)

F I G U R E 3 Effect of fibrates on cisplatin cytotoxicity using HK2 cells. Cell viability after 24 h of incubation in medium with or without
50 μM cisplatin was calculated as 100% for the vehicle group. (a, b) Fenofibrate (1, 10, 100 μM) a or bezafibrate (1, 10, 100 μM) b wasadministered simultaneously with cisplatin. (c) The 2 μM of GW6471, a PPARα inhibitor, was used. Values are expressed as mean ± SEM.
Cis, cisplatin; Beza, bezafibrate; Feno, fenofibrate; GW, GW6471. †p < 0.05 versus vehicle, *p < 0.01 versus cisplatin, n = 8 in each group
(a)

(b)

F I G U R E 4 Effect of fibrates on the anticancer effect of cisplatin on tumor cells, LLC (a), Colon-­26 (b). Cell viability after 24 h ofincubation in medium with or without 50 μM cisplatin was calculated as 100% for the vehicle group. Fenofibrate (100 μM) was administeredsimultaneously with cisplatin. Values are expressed as mean ± SEM. Cis, cisplatin; Feno, fenofibrate. †p < 0.05 versus vehicle. N.S. indicates
not significant. n = 16 in each groupin the long term. However, when high doses of fenofibrate are used in patients using drugs that decrease renal
blood flow or in patients with impaired renal function,

monitoring of serum creatinine is necessary.35 Therefore,
as fenofibrate-­associated increase in serum creatininelevel has been reported, the use of fenofibrate to prevent

1674

|   

cisplatin-­induced acute kidney injury should be precededby the risk–­benefit analysis for patients with normal andimpaired renal function, and the need for monitoring
serum creatinine should be evaluated.
To summarize, this study analyzed an AI tool called
Cascade Eye and two large medical information databases, LINCS and FAERS, to identify candidate drugs that
reduce cisplatin-­induced kidney injury and found that thecandidate drug, fenofibrate, is a drug with high potential
for clinical application as a preventive agent for cisplatin-­induced kidney injury events.
ACKNOWLEDGEMENTS
This research was supported by the Japan Society for the
Promotion of Science (JSPS) KAKENHI (Grant numbers 20K07132, 20H05799, and 20K16077). This study
was supported by FRONTEO Inc. and Support Center
for Advanced Medical Sciences, Tokushima University
Graduate School of Biomedical Sciences.
CONFLICT OF INTEREST
The authors declared no competing interests for this work.
AUTHOR CONTRIBUTIONS
M.G., M.K., and A.M. designed the research. A.M., T.Y.,
A.Y., T.N., and H.H. performed the research. H.H., K.M.,
F.A., N.O., T.S., M.C., K.Y., Y.I.I., H.Y., Y.Z., and K.I. analyzed the data; M.K. and M.G. wrote the manuscript.
ORCID
Mitsuhiro Goda https://orcid.org/0000-0001-5345-1479
Takahiro Niimura https://orcid.org/0000-0003-2033-4246
Masayuki Chuma https://orcid.org/0000-0002-5755-283X
REFERENCES

1. Chovanec M, Abu Zaid M, Hanna N, El-­Kouri N, Einhorn LH,
Albany C. Long-­term toxicity of cisplatin in germ-­cell tumor
survivors. Ann Oncol. 2017;28:2670-­2679.
2. Isnard-­Bagnis C, Moulin B, Launay-­Vacher V, Izzedine H,
Tostivint I, Deray G. Anticancer drug-­induced nephrotoxicity.
Nephrol Ther. 2005;1:101-­114.
3. Arany I, Safirstein RL. Cisplatin nephrotoxicity. Semin Nephrol.
2003;23:460-­464.
4. Karasawa T, Steyger PS. An integrated view of cisplatin-­induced
nephrotoxicity and ototoxicity. Toxicol Lett. 2015;237:219-­227.
5. Ali BH, Al Moundhri MS. Agents ameliorating or augmenting the nephrotoxicity of cisplatin and other platinum compounds: a review of some recent research. Food Chem Toxicol.
2006;44:1173-­1183.
6. Kola I, Landis J. Can the pharmaceutical industry reduce attrition rates. Nat Rev Drug Discov. 2004;3:711-­715.
7. Keenan AB, Jenkins SL, Jagodnik KM, et al. The library of integrated network-­based cellular signatures NIH program: system-­level cataloging of human cells response to perturbations. Cell
Syst. 2018;6:13-­24.

KANDA et al.

8. Duan Q, Reid SP, Clark NR, et al. L1000CDS2: LINCS L1000
characteristic direction signatures search engine. NPJ Syst Biol
Appl. 2016;2:16015.
9. Zamami Y, Niimura T, Koyama T, et al. Search for therapeutic agents for cardiac arrest using a drug discovery tool andlarge-­scale medical information database. Front Pharmacol.
2019;10:1257.
10. Izawa-­Ishizawa Y, Imanishi M, Zamami Y, et al. Developmentof a novel aortic dissection mouse model and evaluation of drug
efficacy using in-­vivo assays and database analyses. J Hypertens.
2019;37:73-­83.
11. Okada N, Niimura T, Zamami Y, et al. Pharmacovigilance evaluation of the relationship between impaired glucose metabolism and BCR-­ABL inhibitor use by using an adverse drug event
reporting database. Cancer Med. 2019;8:174-­181.
12. Sasaoka S, Matsui T, Abe J, et al. Evaluation of the associationof hand-­foot syndrome with anticancer drugs using the US
Food and Drug Administration adverse event reporting system(FAERS) and Japanese adverse drug event report (JADER) databases. Yakugaku Zasshi. 2016;136:507-­515.
13. Goda M, Kanda M, Yoshioka T, et al. Effects of 5-­HT₃ receptor
antagonists on cisplatin-­induced kidney injury. Clin Transl Sci.
2021;14:1906-­1916.
14. Li S, Gokden N, Okusa MD, Bhatt R, Portilla D. Anti-­
inflammatory effect of fibrate protects from cisplatin-­induced
ARF. Am J Physiol Renal Physiol. 2005;289:F469-­F480.
15. Asavapanumas N, Kittayaruksakul S, Meetam P, Muanprasat
C, Chatsudthipong V, Soodvilai S. Fenofibrate down-­
regulates renal OCT2-­mediated organic cation transport via
PPARα-­independent pathways. Drug Metab Pharmacokinet.
2012;27:513-­519.
16. Lian X, Wang G, Zhou H, Zheng Z, Fu Y, Cai L. Anticancer
properties of fenofibrate: a repurposing use. J Cancer.
2018;9:1527-­1537.
17. Jang HS, Noh MR, Jung EM, et al. Proximal tubule cyclophilin
D regulates fatty acid oxidation in cisplatin-­induced acute kidney injury. Kidney Int. 2020;97:327-­339.
18. Livak KJ, Schmittgen TD. Analysis of relative gene expression
data using real-­time quantitative PCR and the 2(-­Delta Delta
C[T]) method. Methods. 2001;25:402-­408.
19. Nojiri T, Hosoda H, Kimura T, et al. Protective effects ofghrelin on cisplatin-­induced nephrotoxicity in mice. Peptides.
2016;82:85-­91.
20. Nagayama T, Tsuchiya A, Arakawa R, et al. Hypolipidemic actionof fenofibrate and bezafibrate in normo-­  and hyper-­lipidemic
animals. Japanese Pharmacol Ther. 1995;23:1047-­1054.
21. Tsuchiya A, Kasai H, Nagayama T, Saitoh K. Comparisonof hypolipidemic action of fenofibrate, bezafibrate, clinofibrate and clofibrate in rats. Japanese Pharmacol Ther.
1995;23:1041-­1046.
22. Jiang B, Wang YJ, Wang H, et al. Antidepressant-­like effects offenofibrate in mice via the hippocampal brain-­derived neurotrophic factor signalling pathway. Br J Pharmacol. 2017;174:​177-­194.
23. Ferguson LB, Most D, Blednov YA, Harris RA. PPAR agonists
regulate brain gene expression: relationship to their effects on
ethanol consumption. Neuropharmacology. 2014;86:397-­407.
24. Yu X, Meng X, Xu M, et al. Celastrol ameliorates cisplatin nephrotoxicity by inhibiting NF-­κB and improving mitochondrial
function. EBioMedicine. 2018;36:266-­280.

DISCOVERY OF PREVENTIVE DRUGS FOR CDDP-­INDUCED AKI

25. Mori K, Nakao K. Neutrophil gelatinase-­associated lipocalinas the real-­time indicator of active kidney damage. Kidney Int.
2007;71:967-­970.
26. Zhang B, Ramesh G, Norbury CC, Reeves WB. Cisplatin-­induced
nephrotoxicity is mediated by tumor necrosis factor-­alpha produced by renal parenchymal cells. Kidney Int. 2007;72:37-­44.
27. Faubel S, Lewis EC, Reznikov L, et al. Cisplatin-­induced acuterenal failure is associated with an increase in the cytokines interleukin (IL)-­1beta, IL-­18, IL-­6, and neutrophil infiltration in
the kidney. J Pharmacol Exp Ther. 2007;322:8-­15.
28. Kawahito Y. The roles of PPARs in immune and inflammatory
system: application for arthritic joint disease. Ensho Saisei.
2003;23:74-­83.
29. Ghonem NS, Assis DN, Boyer JL. Fibrates and cholestasis.
Hepatology. 2015;62:635-­643.
30. Helmy MM, Helmy MW, El-­Mas MM. Additive renoprotection
by pioglitazone and fenofibrate against inflammatory, oxidative
and apoptotic manifestations of cisplatin nephrotoxicity: modulation by PPARs. PLoS One. 2015;10:e0142303.
31. Yang FJ, He YH, Zhou JH. Fenofibrate pre-­treatment suppressed
inflammation by activating phosphoinositide 3 kinase/protein
kinase B (PI3K/Akt) signaling in renal ischemia-­reperfusion
injury. J Huazhong Univ Sci Technol Med Sci. 2015;35:58-­63.
32. Portilla D, Dai G, Peters JM, Gonzalez FJ, Crew MD, Proia
AD. Etomoxir-­induced PPARalpha-­modulated enzymes  | 1675protect during acute renal failure. Am J Physiol Renal Physiol.
2000;278:F667-­F675.
33. Lv J, Wang X, Liu SY, et al. Protective effect of fenofibrate inrenal ischemia reperfusion injury: involved in suppressing kinase 2 (JAK2)/transcription 3 (STAT3)/p53 signaling activation. Pathol Biol (Paris). 2015;63:236-­242.
34. Li T, Zhang Q, Zhang J, Yang G, et al. Fenofibrate induces apoptosis of triple-­negative breast cancer cells via activation of NF-­
κB pathway. BMC Cancer. 2014;14:96.
35. Kostapanos MS, Florentin M, Elisaf MS. Fenofibrate and thekidney: an overview. Eur J Clin Invest. 2013;43:522-­531.

SUPPORTING INFORMATION
Additional supporting information may be found in the
online version of the article at the publisher’s website.
How to cite this article: Kanda M, Goda M,
Maegawa A, et al. Discovery of preventive drugs forcisplatin-­induced acute kidney injury using big data
analysis. Clin Transl Sci. 2022;15:1664-­1675.
doi:10.1111/cts.13282