MicroRNA 483-3p suppresses the expression of DPC4/Smad4 in pancreatic cancer
Jun Haoa, Shuyu Zhangb, Yingqi Zhoua, Xiangui Hua,⇑, Chenghao Shaoa,⇑
aDepartment of Pancreatic Surgery, Changhai Hospital, Second Military Medical University, Shanghai 200433, China
bSchool of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou 215123, China
a r t i c l e i n f o
Received 3 September 2010
Revised 22 November 2010
Accepted 22 November 2010
Available online 27 November 2010
Edited by Tamas Dalmay
a b s t r a c t
Both deregulation of tumor-suppressor genes and misexpression of microRNAs (miRNAs) have been
implicated in the development of pancreatic cancer, but their relationship during this process
remains less clear. Here, we report that the expression of miR-483-3p is strongly enhanced in pan-
creatic cancer tissues compared to side normal tissues using a miRNA-array differential analysis.
Furthermore, DPC4/Smad4 is identified as a target of miR-483-3p and their expression levels are
inversely correlated in human clinical specimens. Ectopic expression of miR-483-3p significantly
represses DPC4/Smad4 protein levels in pancreatic cancer cell lines, and simultaneously promotes
cell proliferation and colony formation in vitro. Our findings identify miR-483-3p as a potent regu-
lator of DPC4/Smad4, which may provide a novel therapeutic strategy for the treatment of DPC4/
Smad4-driven pancreatic cancer.
? ? 2010 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Pancreatic cancer is an aggressive malignancy with one of the
worst mortality rates. It is the sixth leading cause of death from
malignant disease in China and the fourth leading cause of can-
cer-related death in the United States [1–3]. In recent years, there
have been important advances in the understanding of the molec-
ular biology of pancreatic cancer, and genetic analyses have shown
that the genetic basis of this dismal disease is extremely complex
and heterogeneous . It has been suggested that pancreatic can-
cer is associated with the successive accumulation of gene muta-
tions such as oncogene KRAS2 and tumor-suppressor genes
INK4A, TP53 and DPC4/Smad4 [5,6]. Despite extensive research
efforts, the prognosis for pancreatic cancer is the worst among all
cancers due to minimal improvements in its prevention and
treatment, and the 5-year relative survival rate over the past dec-
ades has remained at only 5% for all stages of this disease [1,3].
Therefore, the quest for new associated factors and novel therapeu-
tic targets for pancreatic cancer remains an imperative clinical
Recently, microRNAs (miRNA) have emerged as a critical class
of negative regulators of gene expression. miRNAs are endogenous
small 21–23 nucleotide non-coding RNAs that possess remarkable
evolutionary conservation [7,8]. These small molecules elicit their
regulatory effects by base-pairing to partially complementary
mRNAs and function by at least two mechanisms: degradation of
target mRNA transcripts and inhibition of mRNA translation
[9,10]. Emerging evidence indicates that miRNAs play critical roles
in the regulation of various biological and pathologic processes,
involving cell proliferation, differentiation, apoptosis, and stress
resistance [11–13]. More importantly, it has been suggested that
the development and progression of cancer are associated with
aberrant upregulation or downregulation of specific miRNAs and
their targets in various types of cancer. And certain cancer histo-
types can be classified based on miRNA expression profiles [14–
16]. In pancreatic cancer, a multitude of misexpressed miRNAs
have been reported, such as ‘onco(genic)-miRs’, miR-21 and miR-
155, and ‘tumor suppressor miRs’, miR-29b and the miR-34 and
let-7 families [17,18]. Moreover, it was recently found that miR-
96 functions as a tumor-suppressor gene in pancreatic cancer by
repressing KRAS expression . However, it is less clear whether
there are any other miRNAs targeting these key regulatory genes in
In this study, using a miRNA array-based differential analysis,
we found that miR-483-3p expression levels of pancreatic cancer
tissues were significantly higher than those of the respective side
normal tissues. By computational prediction and luciferase repor-
ter assays, we identified DPC4/Smad4, a central mediator of TGF-
b signal transduction , as a target of miR-483-3p. We also
found that their expression levels were inversely proportional in
pancreatic cancer tissues. Furthermore, we showed that overex-
pression of miR-483-3p in pancreatic cancer cells promoted cell
proliferation and colony formation. Taken together, our results
0014-5793/$36.00 ? 2010 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
⇑Corresponding authors. Fax: +86 21 81873355 (X. Hu), +86 21 81873356
E-mail addresses: email@example.com (X. Hu),
firstname.lastname@example.org (C. Shao).
FEBS Letters 585 (2011) 207–213
journal homepage: www.FEBSLetters.org
suggest that the upregulated miR-483-3p targets tumor-suppres-
sor gene DPC4/Smad4 in pancreatic cancer and that miR-483-3p
may be a potential target for pancreatic cancer therapy.
2. Materials and methods
2.1. Tissue samples
Pancreatic cancer tissues and respective side normal tissues
from 40 patients were obtained postoperatively in 2009 from the
Department of Pancreatic Surgery, Changhai Hospital, Second Mil-
itary Medical University (Shanghai, China). All patients gave
signed, informed consent for their tissues to be used for scientific
research. Ethical approval for the study was obtained from the
Department of General Surgery, Changhai Hospital, Second Mili-
tary Medical University (Shanghai, China). All diagnoses were
based on pathological and/or cytological evidence. The histological
features of the specimens were evaluated by two senior patholo-
gists according to the classification criteria from the WHO
(1990). Tissues were obtained before chemotherapy and radiation
therapy, and were immediately frozen and stored at ?80 ?C prior
to microarray and real-time RT-PCR analyses.
2.2. RNA extraction and real-time RT-PCR
Total RNA was extracted from cells or tissues with Trizol re-
agent according to the instruction (Invitrogen, Carlsbad, CA). The
miR-483-3p level was quantified by quantitative real-time RT-
PCR using Taqman assay kits (Applied Biosystems, Foster City,
CA), with U6 small nuclear RNA as an internal normalized refer-
ence. For the quantification of DPC4/Smad4, PAI, p21, Msx2 and GAP-
DH, extracted RNA was reverse transcribed to cDNA using an
oligo(dT)12primer and Superscript II (Invitrogen). Their relative
levels were measured in triplicate on a Prism 7900 real-time PCR
machine (Applied Biosystems) according to the instruction. The
primers specific for these genes were listed in Supplementary Ta-
2.3. Construction of promoter reporter plasmids
Three fragments containing different regions of the DPC4/
Smad4 3’UTR were each amplified by PCR, using the following
primers:pGL3-UTR-1 (+1 to +2050, relative to the translational stop
CAGTTG-30(reverse); pGL3-UTR-2 (+2201 to +4105) 50-GCTCTA-
pGL3-UTR-3 (+4200 to +6000) 50-GCTCTAGATAGAACGTTCTTTAAA-
ACACAAGTACA-30(forward) and 50-GCTCTAGATGATTTAGTTGGC-
(reverse). Each amplified fragment was
digested by Xba I and inserted downstream of the firefly luciferase
gene in a pGL3-promoter vector (Promega, Madison, WI). The mu-
tant reporter plasmids were constructed using the QuikChange
mutagenesis kit (Stratagene, La Jolla, CA). These constructed
plasmids were sequenced to confirm their orientation.
2.4. Cell culture and quick transfection
The human pancreatic cancer cell lines SW1990 and PANC1
were maintained in DMEM supplemented with 10% FBS and antibi-
otics (100 units/ml penicillin G Sodium Salt, 100 units/ml strepto-
mycin sulfate; Gibco, Grand Island, NY). Cells were grown in a
37 ?C incubator with 5% CO2. Chemically synthesized RNAs, includ-
ing scramble, miR-483-3p mimics and its inhibitor were obtained
from GenePharma (GenePharma, China). For transfection, cells
were grown on 24-well culture plates with 70–80% confluence.
After 24 h, the cells were cotransfected with Renilla luciferase re-
porter (0.1 lg), the above constructed reporter plasmids (0.5 lg),
and chemically synthesized RNA (0.5 lg) by Lipofectamine 2000
transfection reagent (Invitrogen, Carlsbad, CA). After incubation
for 24 h, cells were harvested using lysis buffer for luciferase assay.
2.5. Luciferase assays
Luciferase activity was measured with the Dual-Luciferase Re-
porter Assay System (Promega). Promoter activities were ex-
pressed as the ratio between Firefly luciferase and Renilla
2.6. Western Blot
Treated cells in 6-well-culture clusters were washed twice
with ice-cold PBS and then directly lysed with 200 ll 2?SDS cell
lysis buffer in each well. The lysates were boiled, centrifuged at
10,000 rpm, and then loaded onto 12% SDS–PAGE gel. Samples
were electrophoresed for 4 h and then transferred to Millipore
Immobilon transfer membrane in bio-rad blot apparatus. After
blocking with 5% non-fat milk in PBS-Tween-20 for 1 h at room
temperature, the membranes were blotted with the appropriate
primary antibody overnight at 4 ?C. After TBST washing, they
were incubated with the appropriate secondary antibody linked
to horseradish peroxidase at a 1:2000 dilution for 1 h at room
temperature. After TBST washing, the blot was incubated in
detection reagent (ECL Advance western blotting detection kit,
Amersham Bioscience, Freiburg, Germany) and exposed to a
Hyperfilm ECL film (Pierce, Rockford, IL). Western blots using
the following antibodies: anti-Smad4 (Santa Cruz), E-Cadherin
(BD Biosciences), fibronectin (Sigma), and GAPDH (KangChen
2.7. Cell proliferation assays
Cells were seeded in a 96-well plate at a density of 1 ? 104cells
per well and incubated for 96 h. In vitro growth was measured
using the Cell Counting Kit-8 (CCK-8) (Dojindo Laboratories,
Kumamoto, Japan). The optical density at 450 nm was measured
using a Microplate Reader (Bio-Rad, Hercules, CA), and the
proliferation index was calculated as an experimental OD value/
control OD value. Three independent experiments were done in
2.8. Colony formation
SW1990 or PANC1 cells transfected with the indicated plasmids
were plated at low density (1000 cells per 6 cm plate), incubated
for 10 days, then fixed and stained with crystal violet. Foci and col-
onies containing more than 50 cells were counted using a
2.9. Statistical analysis
Data from at least three independent experiments are ex-
pressed as means ± standard error of the mean (S.E.M.). The differ-
ences between groups were analyzed using Student’s t-test when
only two groups were present, or assessed by one-way analysis
of variance (ANOVA) when more than two groups were compared.
Correlation analysis between relative expressions of miR-483-3p
and Smad4 was done using the Spearman q test. All tests per-
formed were two-sided. Data were considered significant if
P < 0.05 (indicated by ‘‘*’’) and P < 0.001 (indicated by ‘‘**’’).
J. Hao et al./FEBS Letters 585 (2011) 207–213
3.1. Aberrant expression of miRNA-483-3p in pancreatic cancer
To search for miRNAs that may be involved in the develop-
ment of pancreatic cancer, especially among Chinese patients,
we collected three different human clinical specimens and then
used miRNA-array analysis to screen differentially-expressed
miRNAs between pancreatic cancer tissues and respective side
normal tissues. We found that many reported miRNAs were
significantly misexpressed in these cancer samples, including
miR-34a, miR-621, miR-875-3p and miR-145  (Table 1 and
Supplementary Table 2). Besides, the expression of miR-483-3p,
which had not been suggested to be involved in pancreatic cancer
in previous studies, was enhanced in malignant tissues. To further
confirm the miRNA array results, we extended our samples to 40
different clinical specimens from different genders of patients
aged 50–75 years old. Real-time PCR analysis showed that the
expression patterns of miR-34a, miR-145 and miR-621 were con-
sistent with the miRNA array data (Fig. S1). Moreover, miR-483-
3p was also increased significantly in cancer tissues compared
with matched side tissues (Fig. 1A), suggesting that miR-483-3p
may be a novel factor associated with the development of pancre-
3.2. DPC4/Smad4 is a direct target of miRNA-483-3p
To explore the mechanism(s) by which miR-483-3p executes its
function in pancreatic cancer, we first applied three bioinformatic
algorithms (TargetScan, PicTar and miRanda) to identify its poten-
tial target genes. Among these many candidates, DPC4/Smad4 was
selected for further analysis. DPC4/Smad4, a critical effector in
TGF-b signaling pathway , was a regulatory factor in pancreatic
cancer progression and approximately 55% cases of pancreatic ade-
nocarcinomas involve inactivation or lost expression of the DPC4/
Smad4 gene [22,23]. Three binding sites of miR-483-3p were pre-
dicted at positions 1996–2002, 2122–2128 and 4030–4036 in the
30-UTR of DPC4/Smad4 mRNA (Fig. 2A).
To test the hypothesis that DPC4/Smad4 might be a target of
miR-483-3p, we constructed three reporters by putting the wild-
type fragments covering position 1–2050, 2201–4105 or 4200–
6000 from the 30-UTR region of DPC4/Smad4 to the downstream
of the luciferase coding region (named pGL3-UTR1-WT, pGL3-
UTR2-WT and pGL3-UTR3-WT; Fig. 2B). Oligonucleotides of miR-
483-3p mimics or scramble were cotransfected with these reporter
plasmids into human pancreatic cancer cells SW1990 and PANC1,
both of which contain wild-type DPC4/Smad4 gene [24,25]. Lucifer-
ase assay showed that miR-483-3p mimics repressed the activity
of pGL3-UTR1-WT and pGL3-UTR2-WT remarkably, but had no sig-
nificant effect on the reporter activity of pGL3-UTR3-WT (Fig. 2B),
which lacks the miR-483-3p binding site. In contrast, pGL3-UTR1-
MUT and pGL3-UTR2-MUT, in which the putative binding sites of
miR-483-3p are mutated, showed higher luciferase activities than
the respective wild-type ones, suggesting that they are indeed reg-
ulated by endogenous miR-483-3p (Fig. 2B). Moreover, transfec-
tion of miR-483-3p mimics had no interference with activities of
the two reporters (Fig. 2B). These results suggest that DPC4/Smad4
may be a target of miR-483-3p for its regulatory function in pan-
This led us to examine whether ectopic expression of miR-483-
3p could reduce endogenous DPC4/Smad4 protein levels in human
pancreatic cancer cell lines. We overexpressed miR-483-3p mimics
in SW1990 cells and Western blot assays indicated that the level of
DPC4/Smad4 protein was reduced significantly by miR-483-3p
overexpression compared with control treatment (Fig. 2C). The
same results were observed using another human pancreatic can-
cer cell line PANC1 (Fig. 2C). As Smad4 is the common-Smad pro-
tein for the transduction of TGF-b and BMP signals [20,26], the
repression of DPC4/Smad4 by miR-483-3p should impair these
two signaling pathways. Next, we examined the effect of miR-
483-3p on the expression of these pathways’ transcriptional
Summary of significantly differentially expressed miRNAs in pancreatic cancer tissues
compared with matched normal adjacent pancreatic tissues.
miRNA ID FoldChange (caner vs
adjacent normal tissues)
Up regulated miRNAs
Down regulated miRNAs
*Represents a strand derived from the corresponding pre-miRNA.
Fig. 1. Quantitative analyses of relative miR-483-3p and DPC4/Smad4 mRNA levels. The relative expression of miR-483-3p and DPC4/Smad4 was normalized with U6 and
GAPDH levels respectively, in 40 pancreatic cancer tissues and matched normal adjacent pancreatic tissues were analyzed by real-time PCR. The results are presented as
means ± S.E.M. *P < 0.05; **P < 0.001.
J. Hao et al./FEBS Letters 585 (2011) 207–213
targets in PANC1 cells. Real-time PCR analysis showed that the
expression levels of TGF-b signaling target genes PAI [27,28] and
p21 , as well as BMP signaling targets Msx2 [30,31], were sup-
pressed by miR-483-3p overexpression (Fig. 2D), suggesting that
miR-483-3p can regulate DPC4/Smad4-regulated signaling path-
ways. It is known that DPC4/Smad4 is involved in TGF-b-induced
epithelial-mesenchymal transition (EMT) , and that pancreatic
cancers with wild type DPC4/Smad4 show frequent EMT . To
test the possibility that miR-483-3p could regulate the DPC4/
Smad4-mediated EMT process, we transfected PANC1 cells with
miR-483-3p mimics or scramble oligos and simultaneously treated
them with TGF-b. Western blot analysis showed that compared
with TGF-b treatment alone, transfection of miR-483-3p mimics
increased E-cadherin levels while decreasing fibronectin expres-
sion (Fig. 2E), suggesting that miR-483-3p could antagonize
DPC4/Smad4-mediated TGF-b induction of EMT. Taken together,
these data suggest that miR-483-3p may exert its biological func-
tion through regulating the expression of its direct target DPC4/
3.3. Inverse correlation of miR-483-3p and DPC4/Smad4 expression
levels in human pancreatic tumors
In order to further address the biological significance of the
interaction between DPC4/Smad4 and miR-483-3p in pancreatic
cancer, we initially examined DPC4/Smad4 expression in the hu-
Fig. 2. DPC4/Smad4 is a direct target of miR-483-3p. (A) Putative miR-483-3p binding sequences in the 30-UTR of DPC4/Smad4 mRNA. (B) Three different fragments from 30-
UTR region of DPC4/Smad4 were cloned into the downstream of the luciferase reporter gene separately and named as indicated. pGL3-UTR1-WT and pGL3-UTR2-WT were
mutated in every miR-483-3p binding site to generate pGL3-UTR1-MUT and pGL3-UTR2-MUT, respectively. Each of the five plasmids and Renilla luciferase reporter, were
cotransfected into SW1990 and PANC1 cells, either with miR-483-3p mimics or a scramble miRNA (negative control) as indicated. Luciferase activity was assayed 48 h after
transfection. All experiments were repeated at least three times independently. The results are presented as means ± S.E.M. *P < 0.05; **P < 0.001. (C) miR-483-3p Suppresses
expression of endogenous DPC4/Smad4. Western blot was used to examine the expression levels of endogenous DPC4/Smad4 in SW1990 and PANC1 cells 48 h after
transfection. (D) The expression of target genes of DPC4/Smad4 pathway was reduced by miR-483-3p overexpression. Real-time PCR was used to determine the expression
levels of indicated targets of TGF-b and BMP pathways in SW1990 and PANC1 cells 48 h after transfection. (E) miR-483-3p antagonizes DPC4/Smad4-mediated TGF-b
induction of EMT. PANC1 cells were transfected with miR-483-3p mimics or scramble oligos, and treated with TGF-b or mock simultaneously. After 48 h, cells lysate were
examined with indicated antibodies by Western blot.
J. Hao et al./FEBS Letters 585 (2011) 207–213
man clinical specimens used here. It was found that the mRNA le-
vel of DPC4/Smad4 was pronouncedly inhibited in pancreatic can-
cer tissues compared with the normal tissues (Fig. 1B), consistent
with previous studies that DPC4/Smad4 was downregulated in
some cases of pancreatic adenocarcinomas [22,23]. We speculated
that the reduced DPC4/Smad4 expression in pancreatic cancer
could be a result of elevated miR-483-3p expression. Therefore,
Spearman correlation analysis was applied to compare the relative
expression levels of DPC4/Smad4 and miR-483-3p in these human
clinical specimens. We obtained a statistically significant inverse
correlation (R = ?0.628, P = 0.001) in a total of 40 tumors (Fig. 3),
indicating that miR-483-3p expression is inversely correlated with
DPC4/Smad4 in pancreatic cancer, and that upregulated miR-483-
3p in pancreatic cancer suppresses the expression level of DPC4/
Smad4, which in turn accelerates tumorigenesis.
3.4. Overexpression of miRNA-483-3p in pancreatic cancer cell
promotes cell proliferation and colony formation
As our above results indicate that miR-483-3p is overexpressed
in pancreatic cancers and that it may act as an oncomiR, we next
tried to examine whether miR-483-3p has oncogenic functions in
pancreatic cancer cells. The CCK-8 proliferation assay showed that
miR-483-3p mimics significantly promoted the proliferation of
both SW1990 and PANC1 cells (Fig. 4A). Consistent with that, the
colony formation analysis also showed that miR-483-3p stimu-
Fig. 3. DPC4/Smad4 and miR-483-3p expression levels are inversely correlated in human pancreatic tumors. (A) Real-time PCR analyses of the relative expression levels of
DPC4/Smad4 and miR-483-3p in 40 pairs of pancreatic cancer tissue samples. (B) The inverse correlation of DPC4/Smad4 and miR-483-3p expression levels was examined by
Spearman correlation analysis (R = ?0.628, P + 0.001).
Fig. 4. The effect of miR-483-3p on cell proliferation and colony formation. (A) SW1990 and PANC1 cell lines were seeded in a 96-well plate and incubated for 96 h after
transfection. Cell proliferation was measured by CCK-8. (B) 1000 cells were seeded on each plate and transfected as indicated. After 10 days, cells were stained with crystal
violet. Colonies consisting of more than 50 cells were counted. The data are presented as means ± S.E.M. *P < 0.05; **P < 0.001.
J. Hao et al./FEBS Letters 585 (2011) 207–213
lated SW1990 and PANC1 cells to grow more and larger colonies
(Fig. 4B). Conversely, anti-miR-483-3p transfection in SW1990
and PANC1 cells significantly reduced cell proliferation (Fig. 4A)
and resulted in fewer SW1990 or PANC1 colonies (Fig. 4B). These
results suggest that miR-483-3p promotes the proliferation and
anchorage-independent growth of pancreatic cancer cells in vitro.
Pancreatic cancer is an aggressive as well as malignant disease
and is advanced by the successive and accumulated mutations of
genes, including oncogenes KRAS2 and tumor-suppressor genes,
INK4A, TP53 and DPC4/Smad4 [5,6]. The involvement of miRNAs
in various human tumors suggests that they could also have regu-
latory functions in pancreatic cancer. Several miRNAs have been
revealed as ‘onco(genic)-miRs’ or ‘tumor-suppressor miRs’ in-
volved in pancreatic tumor development [17,18]. Yet, the molecu-
lar mechanisms of miRNAs in pancreatic cancer and their
relationship with these regulatory factors are currently poorly
understood. It was recently reported that miRNA-96 was downreg-
ulated in pancreatic cancer and directly targeted oncogene KRAS
for its regulatory function . Therefore miR-96 acts as a tu-
mor-suppressor microRNA in pancreatic cancer and may be re-
garded as a therapeutic target for KRAS-caused pancreatic tumor.
It is known that the genetic basis of pancreatic cancer is extremely
complex and heterogeneous . In most pancreatic cancers, there
are several pathways, such as TGF-b, K-RAS, JNK, Intergrin, and
Hedgehog signalings etc, and processes, including control of G1/S
phase transition and DNA damage, whose component genes are
genetically altered . The deregulation of many tumor-suppres-
sor genes is one of the critical reasons for the initiation and
advancement of pancreatic cancer [5,6]. However, it remains un-
known whether there is any miRNA targeting the tumor-suppres-
sor gene in pancreatic carcinogenesis.
By miRNA-array analysis of human clinical specimens, we
found that miR-483-3p was aberrantly upregulated in pancreatic
cancer tissues compared with side normal tissue. Human miR-
483 is a microRNA located within intron 2 of the IGF2 locus. It
has been found that mature miR-483-3p is overexpressed in malig-
nant mesothelioma and Wilms’ tumors [34,35]. In addition, the
expression level of miR-483-3p is high or extremely high in many
common adult human cancers, comprising 30% of cases of colon,
breast and liver cancers . Together with our findings, it is sug-
gested that miR-483-3p may be used as a novel biomarker and
therapeutic target for pancreatic and other human adult cancers.
Thus it will be clinically useful to study the functional mecha-
nism(s) underlying the oncogenic role of miR-483-3p.
The TGF-b superfamily members are cytokines that play key
roles in regulating adult tissue homeostasis, and deregulation of
its signaling pathway has been associated with various carcinogen-
esis [36,37]. Smad4 is the common Smad protein (Co-Smad), to-
gether with phosphorylated R-Smads (receptor-regulated Smads),
that mediates the transduction and response of TGF-b and BMP sig-
nal [20,26]. It has been reported that the deregulation of DPC4/
Smad4 level is involved in pancreatic tumor progression and
approximately 55% of cases involve inactivation or lost expression
of the DPC4/Smad4 gene [22,23]. Here, we find that miR-483-3p di-
rectly targets the 30UTR of DPC4/Smad4 and that ectopic expression
of miR-483-3p represses DPC4/Smad4 protein level. Besides, over-
expression of miR-483-3p also inhibited the expression of DPC4/
Smad4 downstream targets, such as PAI [27,28], p21  and
Msx2 [30,31], and antagonized DPC4/Smad4-mediated TGF-b
induction of EMT process. Moreover, the expression levels of
miR-483-3p and DPC4/Smad4 are inversely correlated in human
clinical specimens of pancreatic cancer. Thus miR-483-3p plays
an oncogenic role in pancreatic carcinogenesis by regulating a tu-
mor-suppressor gene, DPC4/Smad4. This identified novel regulator,
miR-483-3p, may be used for the diagnosis and therapy of DPC4/
Smad4-driven pancreatic cancer.
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