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AGING 2021, Vol. 13, No. 12
Research Paper
MiR-513b-5p represses autophagy during the malignant progression
of hepatocellular carcinoma by targeting PIK3R3
Wei Jin1,*, Yilei Liang2,*, Shuyou Li3, Guoxiang Lin3, Haiying Liang4, Zhenni Zhang3, Weiming
Zhang3, Rongjun Nie3
1
Department of Hepatobiliary Surgery, Affiliated Wuming Hospital, Guangxi Medical University, Nanning, Guangxi
Province, China
2
Department of Maxillofacial Surgery, Affiliated Wuming Hospital, Guangxi Medical University, Nanning, Guangxi
Province, China
3
Department of Oncology and Intervention, Affiliated Wuming Hospital, Guangxi Medical University, Nanning,
Guangxi Province, China
4
Department of Gynecology, Affiliated Wuming Hospital, Guangxi Medical University, Nanning, Guangxi Province,
China
*
Equal contribution
Correspondence to: Rongjun Nie; email: nrj2001@163.com, https://orcid.org/0000-0003-1888-2868
Keywords: hepatocellular carcinoma, autophagy, progression, miR-513b-5p, PIK3R3
Received: February 19, 2021
Accepted: May 18, 2021
Published: June 13, 2021
Copyright: © 2021 Jin et al. This is an open access article distributed under the terms of the Creative Commons Attribution
License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original
author and source are credited.
ABSTRACT
Hepatocellular carcinoma (HCC) serves as a prevailing global malignancy with severe mortality and extremely
unsatisfactory prognosis, in which autophagy is a fundamental process in liver cancer pathogenesis, but the
mechanisms are poorly understood. MicroRNAs (miRNAs) serve as a type of well-recognized non-coding
regulators and contribute to the modulation of liver cancer development, from the aspects of diagnosis,
progression, and therapy. Here, we aimed to investigate the function of hsa_microRNA-513b-5p (miR-513b-5p)
in regulating autophagy during HCC progression. Specifically, our data showed that miR-513b-5p mimic reduced
the LC3-II and beclin1 expression but enhanced p62 expression in HCC cells. MiR-513b-5p repressed liver cancer
cell proliferation, migration/invasion, and induced apoptosis in vitro. Crucially, miR-513b-5p attenuated tumor
growth of liver cancer cells in vivo. In the mechanical investigation, we identified that PIK3R3 mRNA 3′UTR was
targeted by miR-513b-5p and miR-513b-5p suppressed PIK3R3 expression. PIK3R3 overexpression partly
reversed miR-513b-5p-mediated autophagy, proliferation, and apoptosis of liver cancer cells. Consequently, we
concluded that miR-513b-5p repressed autophagy during the malignant progression of HCC by targeting PIK3R3.
MiR-513b-5p may be applied as a therapeutic target for HCC.
INTRODUCTION
Though previous investigations have explored the
unusual expression of various proteins in HCC, the
mechanism of HCC development is still mostly
undiscovered [3]. Autophagy is a lysosome-related
program and represents an intricate function during
tumorigenesis [4]. When denied growth factors,
nutrients, and oxygen, cancer cells sustain their
durability by autophagy-associated degeneration of
damaged organelles and misfolded proteins [5]. As the
Liver cancer is a prevalent malignancy and the principal
reason for tumor mortality globally, in which
hepatocellular carcinoma (HCC) depicts 70–85% of the
entire liver carcinoma weight [1]. Although there have
been recent improvements, most HCC cases are
identified at an advanced stage, resulting in bad
outcomes and a considerable recurrence frequency [2].
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previous studies, autophagy is a crucial process during
liver cancer development and a potential therapeutic
target for liver cancer therapy (Allaire, 2019 #35;
Huang, 2018 #34; Tang, 2019 #33), but the mechanisms
are poorly understood.
HCCLM3 cells (Figure 1C–1F, Supplementary
Figure 1). Taken together, these results indicate that
miR-513b-5p inhibits autophagy in liver cancer cells.
MiR-513b-5p represses liver cancer cell proliferation
in vitro
MicroRNAs (miRNAs) are extensively expressed in
many species, including viruses, plants, and animals
[6, 7]. MiRNAs serve the non-coding, endogenous, and
small regulators and negatively modulate the targeted
genes' mRNA 3′-untranslated region (3′-UTR) by
causing mRNAs degeneration suppressing protein
translation [8–10]. Multiple miRNAs are reported to
participate in the regulation of liver cancer [11, 12].
Meanwhile, miR-513b-5p has been reported to inhibit
progression of embryonal carcinoma and lung cancer
[13, 14]. Moreover, it has been uncovered that miR-511
reduces migration, invasion, and proliferation of HCC
cells by targeting phosphoinositide-3-kinase regulatory
subunit 3 [15]. MiR-132 represses migration, invasion,
and proliferation of HCC cells through down-regulating
PIK3R3 [16]. PIK3R3 acts as an oncogene of various
cancers, containing glioma, lung cancer, and gastric
cancer [17–19]. However, the impact of miR-513b-5p
on PIK3R3 in HCC is still unreported. As several
miRNAs are involved in the modulation of autophagy in
HCC and based on the crucial role of miR-513b-5p in
cancer development, we selected miR-513b-5p as an
example to evaluate its function in autophagy during
liver cancer progression.
We then further explored the effect of miR-513b-5p on
HCC cell proliferation in vitro, to this end, we
performed MTT assays and colony formation assays in
the HepG2, Huh-7, and HCCLM3 cells. The treatment
of miR-513b-5p suppressed the cell viability in the
HepG2, Huh-7, and HCCLM3 cells (Figure 2A and 2B,
Supplementary Figure 2A). Similarly, the colony
formation ability of HepG2, Huh-7, and HCCLM3 cells
was attenuated by miR-513b-5p (Figure 2C and 2D,
Supplementary Figure 2B). Collectively, it suggests that
miR-513b-5p represses liver cancer cell proliferation in
vitro.
MiR-513b-5p reduces tumor growth of liver cancer
cells in vivo
We then further assessed the role of miR-513b-5p
during tumor growth of HepG2 cells in vivo.
Interestingly, the treatment of miR-513b-5p mimic
remarkably alleviated the tumor growth phenotypes,
including tumor size, tumor weight, and tumor volume
(Figure 3A–3C). These data indicate that miR-513b-5p
reduces tumor growth of liver cancer cells in vivo.
In the present study, we were interested in the miR513b-5p function in the modulation of autophagy during
liver cancer progression. We demonstrated that miR513b-5p attenuated autophagy during the malignant
progression of liver cancer by targeting PIK3R3.
MiR-513b-5p suppresses migration/invasion and
enhances apoptosis of liver cancer cells in vitro
Given that the migration, invasion, and apoptosis
are the crucial phenotype of cancer progression, we
then concerned about the impact of miR-513b-5p on
liver cancer cells migration/invasion and apoptosis
in vitro. We found that miR-513b-5p mimic
significantly restrained the migration/invasion
capability of HepG2, Huh-7, and HCCLM3 cells
(Figure 4A and 4B, Supplementary Figure 3A).
Moreover, HepG2, Huh-7, and HCCLM3 cells
apoptosis was induced in the miR-513b-5p mimictreated cells (Figure 4C and 4D, Supplementary
Figure 3B). Taken together, these data indicate that
miR-513b-5p suppresses migration/invasion and
enhances apoptosis of liver cancer cells in vitro.
RESULTS
MiR-513b-5p inhibits autophagy in liver cancer cells
Firstly, we analyzed the expression of miR-513b-5p in
the normal liver LO2 cells and liver cancer cells,
including H7402, HCCLM3, HepG2 and Huh-7 cells.
We observed that we miR-513b-5p was decreased in the
liver cancer cells compared with the normal liver cells
(Figure 1A). We then were interested in the function of
miR-513b-5p in the regulation of autophagy in HCC,
we analyzed the autophagy related markers, such as
LC3, beclin1, and p62 in HCC cells. For this purpose,
the liver cancer cell lines, including HepG2 and Huh-7
cells, were treated with miR-513b-5p and the expression
of miR-513b-5p was enhanced in the cells (Figure 1B).
Functionally, the treatment of miR-513b-5p mimic
repressed the LC3-II and beclin1 expression but
induced p62 expression in the HepG2, Huh-7, and
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PIK3R3 is targeted by miR-513b-5p in liver cancer
cells
Next, we tried to explore the potential mechanism
underlying miR-513b-5p-mediated HCC progression.
The predicted analysis demonstrated the potential
binding of miR-513b-5p with PIK3R3 mRNA 3′UTR
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PIK3R3 is involved in miR-513b-5p-inhibited
autophagy liver cancer cells
(Figure 5A). MiR-513b-5p mimic remarkably repressed
the luciferase activities of PIK3R3 mRNA 3′UTR in the
HepG2, Huh-7, and HCCLM3 cells (Figure 5B and 5C,
Supplementary Figure 4). Both of the mRNA and
protein levels of PIK3R3 were down-regulated by miR513b-5p mimic in the HepG2, Huh-7, and HCCLM3
cells (Figure 5D–5F, Supplementary Figure 3B).
Collectively, it indicates that PIK3R3 is targeted by
miR-513b-5p in liver cancer cells.
Furthermore, the treatment of miR-513b-5p mimic
repressed the LC3-II expression but induced p62
expression in the HepG2 and Huh-7 cells, in which the
PIK3R3 overexpression partly reversed this effect in
the cells (Figure 6A and 6B). Meanwhile, PIK3R3
overexpression partly rescued the cell proliferation and
Figure 1. MiR-513b-5p inhibits autophagy in liver cancer cells. (A) The measurement of miR-513b-5p expression using qPCR. (B–F)
The HepG2 and Huh-7 cells were treated with miR-513b-5p mimic. (B) The measurement of miR-513b-5p expression using qPCR. (C–F) The
detection of LC3, beclin1, and p62 expression using Western blot analysis.
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blocked the cell apoptosis, which were mediated by
miR-513b-5p mimic in the HepG2, Huh-7, and
HCCLM3 cells (Figure 6C–6F, Supplementary
Figure 5), implying that PIK3R3 is involved in
miR-513b-5p-inhibited autophagy liver cancer cells.
Moreover, autophagy inhibitor 3-MA enhanced
miR-513b-5p mimic-promoted cell proliferation and
miR-513b-5p mimic-inhibited cell apoptosis in the
HepG2, Huh-7, and HCCLM3 cells (Figure 7,
Supplementary Figure 6).
Figure 2. MiR-513b-5p represses liver cancer cell proliferation in vitro. (A–D) The HepG2 and Huh-7 cells were treated with
miR-513b-5p mimic. (A and B) The analysis of cell proliferation using MTT assays. (C and D) The analysis of cell proliferation using colony
formation assays.
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DISCUSSION
phagy and relieves chemoresistance by targeting
FOXO3 sin HCC cells [24]. In addition, it has been
reported that miR-513b-5p enhances P53 expression by
repressing IRF2 to decreases proliferation of testicular
embryonal carcinoma cells [14]. MiR-513b-5p targets
DUSP11 and is involved in AZIN1-AS1-promoted lung
cancer progression [13]. Our data showed that miR513b-5p decreased autophagy-related phenotypes in
liver cancer cells. miR-513b-5p repressed proliferation
and migration/invasion, and enhanced apoptosis of liver
cancer cell in vitro and reduced tumor growth of liver
cancer cells in vivo. These data indicate a novel function
of miR-513b-5p in the autophagy modulation and liver
cancer progression, providing important evidence of the
role of miR-513b-5p in malignancies. In this study, we
just evaluated the function of miR-513b-5p as a
It has been well-identified that autophagy is the critical
cellular process and the regulators of autophagy are
potential therapeutic targets for the liver cancer. The
HGF/MET signaling controls autophagy and
metabolism to regulate chemoresistance of liver cancer
[20]. Autophagy regulates glycolytic metabolism by
hexokinase 2 degradation in liver cancer [21]. Long
noncoding RNA HULC enhances liver cancer
progression via repressing PTEN through autophagymediated miR-15a [22]. Moreover, several miRNAs
have been reported to regulate autophagy in liver cancer
cells. MiR-638 promotes cell autophagy and apoptosis
through repressing EZH2 in liver cancer [23]. MiR-223
enhancement attenuates doxorubicin-stimulated auto-
Figure 3. MiR-513b-5p reduces tumor growth of liver cancer cells in vivo. (A–C) The analysis of tumor growth of HepG2 cells treated
with miR-513b-5p mimic using tumorigenicity assays in the nude mice. The tumor size (Scale bar = 10 mm), tumor weight, and tumor volume
were shown.
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example in the modulation of autophagy in HCC,
Whether or not have other miRNAs as well as miR513b-5p to suppress autophagy in HCC progression and
then synergy with miR-513b-5p should be explored in
future investigations. Multiple factors may affect the
outcome of miR-513b-5p-mediated autophagy and
cancer progression. According to the previous study,
several upstream factors, including long non-coding
RNA FTX [25], long non-coding RNA UCA1 [26],
long non-coding RNA LINC00861 [27], long noncoding RNA AZIN1-AS1 [13], circular RNA G004213
[28], and circular RNA circ_LARP4 [29], in the
modulation of cancer progression, such as pancreatic
cancer, osteosarcoma, cervical cancer, non-small cell
lung cancer, and ovarian cancer. Whether these factors
modulated miR-513b-5p-mediated autophagy in liver
cancer should be validated in future investigations.
Moreover, the miR-513b-5p mimic-enhanced p62 is
associated with aggresome formation and maintain the
survival of HCC. Thus, the miR-513b-5p is not
sufficient to suppress the HCC relapse. More evidence
should be constructed in future investigations to
validate this issue.
Previous investigations have demonstrated the function
of PIK3R3. It has been reported that miR‑601 is a
potential cancer inhibitor by repressing PIK3R3 in HCC
cells [30]. MiR-1287 represses the migration, invasion,
and proliferation of HCC cells by targeting PIK3R3
[31]. In our study, we identified that PIK3R3 was
targeted by miR-513b-5p in liver cancer cells and
involved in miR-513b-5p-inhibited autophagy liver
cancer cells. Our finding provides new knowledge of
the mechanism involving PIK3R3 of miR-513b-5pmediated cancer progression. Meanwhile, PIK3R3 may
be just one of the downstream targets of PIK3R3 in the
modulation of cancer development, more potential
factors response to miR-513b-5p-regulated cancer
progression need to be explored in other investigations.
In addition, some reported factors, including E2F5 [26],
PTEN/AKT/mTOR signaling [27], DUSP11 [13],
PRPF39 [28], and LARP4 [29], are involved in
Figure 4. MiR-513b-5p suppresses migration/invasion and enhances apoptosis of liver cancer cells in vitro. (A–D) The HepG2
and Huh-7 cells were treated with miR-513b-5p mimic. (A and B) The analysis of cell migration/invasion using transwell assays. (C and D) The
analysis of cell apoptosis using flow cytometry.
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miR-513b-5p regulated cancer progression. The
correlation of miR-513b-5p with these factors in the
regulation of tumorigenesis and autophagy in liver
cancer should be confirmed in future studies. There are
still some limitations of this study. For example, we just
used the miR-513b-5p mimic but not miR-513b-5p
inhibitor to investigate the function of miR-513b-5p in
HCC cells, the effect of miR-513b-5p inhibitor on
autophagy in HCC cells needs to validate in further
experiments. Meanwhile, we just evaluated the effect of
miR-513b-5p on HCC cell growth in vivo, the function
of miR-513b-5p/ PIK3R3 needs to be confirmed in the
Figure 5. PIK3R3 is targeted by miR-513b-5p in liver cancer cells. (A) The interaction prediction analysis of miR-513b-5p with PIK3R3
mRNA 3′UTR using ENCORI online database. (B–E) The HepG2 and Huh-7 cells were treated with miR-513b-5p mimic. (B and C) The analysis
of luciferase activities using luciferase reporter gene assays. (D and E) The analysis of PIK3R3 mRNA expression using qPCR. (F) The detection
of PIK3R3 expression using Western blot analysis.
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Figure 6. PIK3R3 is involved in miR-513b-5p-inhibited autophagy liver cancer cells. (A–F) The HepG2 and Huh-7 cells were treated
with miR-513b-5p mimic and pcDNA3.1- PIK3R3. (A and B) The detection of LC3, beclin1, and p62 expression using Western blot analysis.
(C and D) The analysis of cell proliferation using MTT assays. (E and F) The analysis of cell apoptosis using flow cytometry.
Figure 7. Autophagy inhibitor 3-MA reverses miR-513b-5p-mediated liver cancer progression in vitro. (A–F) The HepG2 and
Huh-7 cells were treated with miR-513b-5p mimic and 3-MA (5mM). (A and B) The analysis of cell proliferation using MTT assays. (C and D)
The analysis of cell apoptosis using flow cytometry. (E and F) The analysis of cell migration/invasion using transwell assays.
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model. Importantly, the clinical significance of miR513b-5p in HCC should be assessed in clinical HCC
samples. This study provides the new knowledge of the
function of miR-513b-5p in regulation autophagy
during HCC and the correlation of miR-513b-5p with
PIK3R3 in this process. The therapeutic agents or
strategies of targeting miR-513b-5p/ PIK3R3 axis
should be developed and designed and may benefit the
routine clinical practice in HCC. Meanwhile, it could
promote the application of miR-513b-5p to be a
potential drug in HCC.
Western blot analysis
Total proteins were obtained from the mice tissues or
cells with RIPA buffer (CST, USA). Protein
concentrations were analyzed by applying the BCA
Protein Quantification Kit (Abbkine, USA). Same
concentration of protein was divided by SDS-PAGE
(12% polyacrylamide gels), transferred to PVDF
membranes (Millipore, USA) in the subsequent step. The
membranes were hindered with 5% milk and hatched
overnight at 4°C with the primary antibodies for PIK3R3
(Abcam, USA), LC3 (Abcam, USA), beclin1 (Abcam,
USA), p62 (Abcam, USA), and β-actin (Abcam, USA).
Then, the corresponding second antibodies (Abcam,
USA) were used for hatching the membranes 1 hour at
room temperature, followed by the visualization by using
an Odyssey CLx Infrared Imaging System.
We concluded that miR-513b-5p repressed autophagy
during the malignant progression of HCC by targeting
PIK3R3. MiR-513b-5p may be applied as a therapeutic
target for HCC.
MATERIALS AND METHODS
Colony formation assays
Cell culture
The HCC cells were transfected as the indication,
digested and suspended as single cells, seeded into
6-well plates with 1000 cells in each well. The cells
were placed in incubator for two weeks, and the
medium was changed every three days till the visible
clones formed. The formed clones were stained by 0.5%
crystal violate resolved in methanol, captured and
counted by a microscope (Leica, Germany).
The LO2, H7402, HCCLM3, HepG2, and Huh-7 cells
were obtained in American Type Tissue Culture
Collection. The cells were cultured in the DMEM (BI,
USA) containing 0.1 mg/mL streptomycin (BI, USA),
100 units/mL penicillin (BI, USA), and 10% fetal
bovine serum (BI, USA), at a condition of 37°C with
5% CO2. The lentiviral plasmids carrying miR-196a-5p
mimic/inhibitor, and pcDNA3.1- PIK3R3 were
synthesized and obtained (Genscript, China). The
autophagy inhibitor 3-Methyladenine (3-MA) were
purchased from Selleck (USA).
Tumorigenicity
The tumor growth of liver cancer cells in vivo was
analyzed in nude mice of Balb/c (male, 4-week-old)
(n = 5). About 1 × 107 cells HepG2 cells treated with
miR-513b-5p mimic A. After 5 days of injection, we
measured tumor growth every 5 days. We sacrificed
the mice after 30 days of injection, and tumors were
scaled. The width and length of tumor, and the body
weight of mice were measured at indicated time.
Tumor volume was calculated by the formula: width
(mm)2 × length (mm)/2. The mice were anesthetized to
death when tumor size reached 1000 mm 3, and the
tumors were collected. Animal care and method
procedures were authorized by the Animal Ethics
Committee of Affiliated Wuming Hospital, Guangxi
Medical University.
Quantitative reverse transcription-PCR (qRT-PCR)
The RNA was extracted from BC cells by using TriZol
reagent (Thermo) after treatment, reverse transcribed
to cDNA by using Super Script III kit (Invitrogen).
Subsequently, the relative level was quantified by
SYBR Premix kit (Takara, Japan), and normalized
to GAPDH and 18 s. The results were calculated with
2-△△Ct method. All primers were obtained from RiboBio
(China).
MTT assays
The cell viability was measured by MTT assays in
the HepG2 and Huh-7 cells. Briefly, after the
indicated treatment, about 2 × 104 cells were put into
96 wells and cultured for 12 hours. After indicated
treatment, the cells were added with the MTT
solution (10 μL, 5 mg/mL) and cultured for an extra
4 hours. Discarded medium, and 150 μL DMSO was
used to treat the wells. An ELISA browser was
applied to analyze the absorbance at 570nm (Bio-Tek
EL 800, USA).
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Transwell assays
The migration and invasion ability of HCC cells were
determined via using a transwell chamber (Corning,
USA). To detect migration, HCC cells (1 × 105
cells/well) transfected as the indication were seeded into
the upper chambers with FBS-free medium, while the
lower chambers were filled with complete DMEM
medium. After 24 hours incubation, the membranes of
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upper chambers were fixed by 4% paraformaldehyde
for 15 min, and stained by 0.5% crystal violet for 30
minutes. The migrated cells were photographed and
counted. For cell invasion, the process was similar with
that of migration experiment, only that the upper
chambers were coated with Matrigel (BD Bioscience,
USA).
FUNDING
Analysis of cell apoptosis
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This research did not receive any specific grant from
funding agencies in the public, commercial, or not-forprofit sectors.
REFERENCES
For cell apoptosis detection, the apoptotic cells were
stained with an FITC-Annexin V/PI detection kit (CST,
USA). In brief, about 2 × 105 HepG2 and Huh-7 cells
were plated on 6-well dishes. And the cells were
harvested, washed with PBS, then stained with FITCAnnexin V (5 μL) and PI (5 μL) for 10 minutes,
respectively. The samples were then detected in a flow
cytometry (BD Biosciences, USA).
Luciferase reporter gene assay
The potential binding sites of miR-513b-5p and the
3′UTR region of PIK3R3 were predicted by ENCORI
website. The wild type sequences of the 3′UTR region
of PIK3R3 were cloned into the pmirGLO vectors
(Promega, USA) to obtain the PIK3R3-WT. The sitespecific mutated sequences of the 3′UTR of PIK3R3
were inserted into pmirGLO vectors to obtain the
PIK3R3-Mut. The cells were transfected with PIK3R3WT and Mut along with miR-513b-5p mimic. After 24
hours incubation, the cells were lysed and the luciferase
intensity was detected by a Dual Luciferase assay kit
(Promega, USA). As control, the luciferase activities of
Renilla were measured.
Statistical analysis
Data were expressed as mean ± SD, and the statistical
analysis was presented: *P < 0.05, **P < 0.01, ***P <
0.001, in which P < 0.05 were considered as statistically
significant. The unpaired Student’s t-test and one-way
ANOVA was used to compare the difference.
AUTHOR CONTRIBUTIONS
Wei Jin and Yilei Liang designed and performed
experiments, analysed data and wrote the paper; Shuyou
Li and Guoxiang Lin designed and performed
experiments; Haiying Liang, Zhenni Zhang, Weiming
Zhang, and Rongjun Nie designed experiments,
analysed data and wrote the paper.
CONFLICTS OF INTEREST
The authors declare no conflicts of interest related to
this study.
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SUPPLEMENTARY MATERIALS
Supplementary Figures
Supplementary Figure 1. MiR-513b-5p inhibits autophagy in liver cancer cells. (A–E) The HCCLM3 cells were treated with miR513b-5p mimic. (A) The measurement of miR-513b-5p expression using qPCR. (B–E) The detection of LC3, beclin1, and p62 expression using
Western blot analysis.
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Supplementary Figure 2. MiR-513b-5p represses liver cancer cell proliferation in vitro. (A and B) The HCCLM3 cells were treated
with miR-513b-5p mimic. (A) The analysis of cell proliferation using MTT assays. (B) The analysis of cell proliferation using colony formation
assays.
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Supplementary Figure 3. MiR-513b-5p suppresses migration/invasion and enhances apoptosis of liver cancer cells in vitro.
(A and B) The HCCLM3 cells were treated with miR-513b-5p mimic. (A) The analysis of cell migration/invasion using transwell assays. (B) The
analysis of cell apoptosis using flow cytometry.
Supplementary Figure 4. PIK3R3 is targeted by miR-513b-5p in liver cancer cells. (A–C) The HCCLM3 cells were treated with miR513b-5p mimic. (A) The analysis of luciferase activities using luciferase reporter gene assays. (B) The analysis of PIK3R3 mRNA expression
using qPCR. (C) The detection of PIK3R3 expression using Western blot analysis.
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Supplementary Figure 5. PIK3R3 is involved in miR-513b-5p-inhibited progression of liver cancer in vitro. (A and B) The HCCLM3
cells were treated with miR-513b-5p mimic and pcDNA3.1- PIK3R3. (B) The analysis of cell apoptosis using flow cytometry. (C and D) The
HepG2 and Huh-7 cells were treated with miR-513b-5p mimic and pcDNA3.1- PIK3R3. The analysis of cell migration/invasion using transwell
assays. (E) The HCCLM3 cells were treated with miR-513b-5p mimic and pcDNA3.1- PIK3R3. The analysis of cell migration/invasion using
transwell assays.
Supplementary Figure 6. Autophagy inhibitor 3-MA reverses miR-513b-5p-mediated liver cancer progression in vitro. (A–C)
The HCCLM3 cells were treated with miR-513b-5p mimic and 3-MA (5 mM). (A) The analysis of cell proliferation using MTT assays. (B) The
analysis of cell apoptosis using flow cytometry. (C) The analysis of cell migration/invasion using transwell assays.
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