Purpose: Retinoblastoma (RB) is a primary pediatric ocular malignancy that can be fatal with inadequate treatment. While multimodal treatments are applied for eye salvage, vision loss and metastasis can occur in some patients. The present study aimed to explore key pathways and factors in RB pathogenesis, which could be potential targets for novel RB treatments. Methods: RNA sequencing was performed on three RB tissues and referenced with three normal retinas. Differentially expressed genes (DEGs) were identified from sequencing data and further analyzed with clustering analysis, function and pathway enrichment, protein-protein interaction (PPI), and data-mining analysis in order to screen for tumorigenic relevancy. Results: A total of 331 DEGs were identified by clustering analysis of RB tissues, and the expression patterns were significantly distinguishable from normal retinas. Function and pathway enrichment and PPI analysis together showed that cell cycle was the most prominently upregulated pathway found in RB tissues. Following comprehensive bioinformatic analyses, six key genes relevant to cell cycle regulation were identified, namely BUB1, RRM2, TPX2, UBE2C, NUSAP1, and DTL. Conclusions: Cell cycle pathway and six relevant genes may be potential key factors in RB tumorigenesis and laying the foundation for prospective investigation on development of novel targeted therapies.

1.
Ritchie ME, Phipson B, Wu D, Hu Y, Law CW, Shi W, et al. limma powers differential expression analyses for RNA-sequencing and microarray studies. Nucleic Acids Res. 2015;43(7):e47.
2.
Dennis
G
 Jr
,
Sherman
BT
,
Hosack
DA
,
Yang
J
,
Gao
W
,
Lane
HC
, et al
DAVID: Database for Annotation, Visualization, and Integrated Discovery
.
Genome Biol
.
2003
;
4
(
5
):
3
.
[PubMed]
1474-7596
3.
Ogata
H
,
Goto
S
,
Sato
K
,
Fujibuchi
W
,
Bono
H
,
Kanehisa
M
. KEGG: Kyoto Encyclopedia of Genes and Genomes. Nucleic Acids Res
1999
;27(1):29-34.
4.
Szklarczyk
D
,
Franceschini
A
,
Kuhn
M
,
Simonovic
M
,
Roth
A
,
Minguez
P
, et al
The STRING database in 2011: functional interaction networks of proteins, globally integrated and scored
.
Nucleic Acids Res
.
2011
Jan
;
39
(
Database issue
):
D561
8
.
[PubMed]
0305-1048
5.
Shannon
P
,
Markiel
A
,
Ozier
O
,
Baliga
NS
,
Wang
JT
,
Ramage
D
, et al
Cytoscape: a software environment for integrated models of biomolecular interaction networks
.
Genome Res
.
2003
Nov
;
13
(
11
):
2498
504
.
[PubMed]
1088-9051
6.
Chin
CH
,
Chen
SH
,
Wu
HH
,
Ho
CW
,
Ko
MT
,
Lin
CY
. cytoHubba: identifying hub objects and sub-networks from complex interactome. BMC Syst Biol
2014
;8 Suppl 4S11.
7.
Tang
Z
,
Li
C
,
Kang
B
,
Gao
G
,
Li
C
,
Zhang
Z
.
GEPIA: a web server for cancer and normal gene expression profiling and interactive analyses
.
Nucleic Acids Res
.
2017
Jul
;
45
W1
:
W98
102
.
[PubMed]
0305-1048
8.
Friend
SH
,
Bernards
R
,
Rogelj
S
,
Weinberg
RA
,
Rapaport
JM
,
Albert
DM
, et al
A human DNA segment with properties of the gene that predisposes to retinoblastoma and osteosarcoma
.
Nature
.
1986
Oct
;
323
(
6089
):
643
6
.
[PubMed]
0028-0836
9.
Knudson
AG
 Jr
.
Mutation and cancer: statistical study of retinoblastoma
.
Proc Natl Acad Sci USA
.
1971
Apr
;
68
(
4
):
820
3
.
[PubMed]
0027-8424
10.
Lee
C
,
Chang
JH
,
Lee
HS
,
Cho
Y
.
Structural basis for the recognition of the E2F transactivation domain by the retinoblastoma tumor suppressor
.
Genes Dev
.
2002
Dec
;
16
(
24
):
3199
212
.
[PubMed]
0890-9369
11.
Dimaras
H
,
Khetan
V
,
Halliday
W
,
Orlic
M
,
Prigoda
NL
,
Piovesan
B
, et al
Loss of RB1 induces non-proliferative retinoma: increasing genomic instability correlates with progression to retinoblastoma
.
Hum Mol Genet
.
2008
May
;
17
(
10
):
1363
72
.
[PubMed]
0964-6906
12.
Yu
H
,
Tang
Z
.
Bub1 multitasking in mitosis
.
Cell Cycle
.
2005
Feb
;
4
(
2
):
262
5
.
[PubMed]
1538-4101
13.
Ricke
RM
,
Jeganathan
KB
,
van Deursen
JM
.
Bub1 overexpression induces aneuploidy and tumor formation through Aurora B kinase hyperactivation
.
J Cell Biol
.
2011
Jun
;
193
(
6
):
1049
64
.
[PubMed]
0021-9525
14.
Pinto
M
,
Vieira
J
,
Ribeiro
FR
,
Soares
MJ
,
Henrique
R
,
Oliveira
J
, et al
Overexpression of the mitotic checkpoint genes BUB1 and BUBR1 is associated with genomic complexity in clear cell kidney carcinomas
.
Cell Oncol
.
2008
;
30
(
5
):
389
95
.
[PubMed]
1570-5870
15.
Piao
J
,
Zhu
L
,
Sun
J
,
Li
N
,
Dong
B
,
Yang
Y
, et al
High expression of CDK1 and BUB1 predicts poor prognosis of pancreatic ductal adenocarcinoma
.
Gene
.
2019
Jun
;
701
:
15
22
.
[PubMed]
0378-1119
16.
Li
L
,
Xu
DB
,
Zhao
XL
,
Hao
TY
.
Combination analysis of Bub1 and Mad2 expression in endometrial cancer: act as a prognostic factor in endometrial cancer
.
Arch Gynecol Obstet
.
2013
Jul
;
288
(
1
):
155
65
.
[PubMed]
0932-0067
17.
Fan
H
,
Villegas
C
,
Wright
JA
.
Ribonucleotide reductase R2 component is a novel malignancy determinant that cooperates with activated oncogenes to determine transformation and malignant potential
.
Proc Natl Acad Sci USA
.
1996
Nov
;
93
(
24
):
14036
40
.
[PubMed]
0027-8424
18.
Fan
H
,
Villegas
C
,
Huang
A
,
Wright
JA
.
The mammalian ribonucleotide reductase R2 component cooperates with a variety of oncogenes in mechanisms of cellular transformation
.
Cancer Res
.
1998
Apr
;
58
(
8
):
1650
3
.
[PubMed]
0008-5472
19.
Aye
Y
,
Li
M
,
Long
MJ
,
Weiss
RS
.
Ribonucleotide reductase and cancer: biological mechanisms and targeted therapies
.
Oncogene
.
2015
Apr
;
34
(
16
):
2011
21
.
[PubMed]
0950-9232
20.
Li
C
,
Zheng
J
,
Chen
S
,
Huang
B
,
Li
G
,
Feng
Z
, et al
RRM2 promotes the progression of human glioblastoma
.
J Cell Physiol
.
2018
Oct
;
233
(
10
):
6759
67
.
[PubMed]
0021-9541
21.
Chen
CW
,
Li
Y
,
Hu
S
,
Zhou
W
,
Meng
Y
,
Li
Z
, et al
DHS (trans-4,4′-dihydroxystilbene) suppresses DNA replication and tumor growth by inhibiting RRM2 (ribonucleotide reductase regulatory subunit M2)
.
Oncogene
.
2019
Mar
;
38
(
13
):
2364
79
.
[PubMed]
0950-9232
22.
Rahman
MA
,
Amin
AR
,
Wang
X
,
Zuckerman
JE
,
Choi
CH
,
Zhou
B
, et al
Systemic delivery of siRNA nanoparticles targeting RRM2 suppresses head and neck tumor growth
.
J Control Release
.
2012
May
;
159
(
3
):
384
92
.
[PubMed]
0168-3659
23.
Rahman
MA
,
Amin
AR
,
Wang
D
,
Koenig
L
,
Nannapaneni
S
,
Chen
Z
, et al
RRM2 regulates Bcl-2 in head and neck and lung cancers: a potential target for cancer therapy
.
Clin Cancer Res
.
2013
Jul
;
19
(
13
):
3416
28
.
[PubMed]
1078-0432
24.
Ma
S
,
Rong
X
,
Gao
F
,
Yang
Y
,
Wei
L
.
TPX2 promotes cell proliferation and migration via PLK1 in OC
.
Cancer Biomark
.
2018
;
22
(
3
):
443
51
.
[PubMed]
1574-0153
25.
Liu
HC
,
Zhang
Y
,
Wang
XL
,
Qin
WS
,
Liu
YH
,
Zhang
L
, et al
Upregulation of the TPX2 gene is associated with enhanced tumor malignance of esophageal squamous cell carcinoma
.
Biomed Pharmacother
.
2013
Oct
;
67
(
8
):
751
5
.
[PubMed]
0753-3322
26.
Zou
Z
,
Zheng
B
,
Li
J
,
Lv
X
,
Zhang
H
,
Yu
F
, et al
TPX2 level correlates with cholangiocarcinoma cell proliferation, apoptosis, and EMT
.
Biomed Pharmacother
.
2018
Nov
;
107
:
1286
93
.
[PubMed]
0753-3322
27.
Liang
B
,
Zheng
W
,
Fang
L
,
Wu
L
,
Zhou
F
,
Yin
X
, et al
Overexpressed targeting protein for Xklp2 (TPX2) serves as a promising prognostic marker and therapeutic target for gastric cancer
.
Cancer Biol Ther
.
2016
Aug
;
17
(
8
):
824
32
.
[PubMed]
1538-4047
28.
Shen
Z
,
Jiang
X
,
Zeng
C
,
Zheng
S
,
Luo
B
,
Zeng
Y
, et al
High expression of ubiquitin-conjugating enzyme 2C (UBE2C) correlates with nasopharyngeal carcinoma progression
.
BMC Cancer
.
2013
Apr
;
13
(
1
):
192
.
[PubMed]
1471-2407
29.
Li
L
,
Li
X
,
Wang
W
,
Gao
T
,
Shi
Z
.
UBE2C is involved in the functions of ECRG4 on esophageal squamous cell carcinoma
.
Biomed Pharmacother
.
2018
Feb
;
98
:
201
6
.
[PubMed]
0753-3322
30.
Zhang
J
,
Liu
X
,
Yu
G
,
Liu
L
,
Wang
J
,
Chen
X
, et al
UBE2C Is a Potential Biomarker of Intestinal-Type Gastric Cancer With Chromosomal Instability
.
Front Pharmacol
.
2018
Aug
;
9
:
847
.
[PubMed]
1663-9812
31.
Liu
G
,
Zhao
J
,
Pan
B
,
Ma
G
,
Liu
L
.
UBE2C overexpression in melanoma and its essential role in G2/M transition
.
J Cancer
.
2019
May
;
10
(
10
):
2176
84
.
[PubMed]
0378-2360
32.
Gordon
CA
,
Gulzar
ZG
,
Brooks
JD
.
NUSAP1 expression is upregulated by loss of RB1 in prostate cancer cells
.
Prostate
.
2015
Apr
;
75
(
5
):
517
26
.
[PubMed]
0270-4137
33.
Okamoto
A
,
Higo
M
,
Shiiba
M
,
Nakashima
D
,
Koyama
T
,
Miyamoto
I
, et al
Down-Regulation of Nucleolar and Spindle-Associated Protein 1 (NUSAP1) Expression Suppresses Tumor and Cell Proliferation and Enhances Anti-Tumor Effect of Paclitaxel in Oral Squamous Cell Carcinoma
.
PLoS One
.
2015
Nov
;
10
(
11
):
e0142252
.
[PubMed]
1932-6203
34.
Liu
Z
,
Guan
C
,
Lu
C
,
Liu
Y
,
Ni
R
,
Xiao
M
, et al
High NUSAP1 expression predicts poor prognosis in colon cancer
.
Pathol Res Pract
.
2018
Jul
;
214
(
7
):
968
73
.
[PubMed]
0344-0338
35.
Qian
Z
,
Li
Y
,
Ma
J
,
Xue
Y
,
Xi
Y
,
Hong
L
, et al
Prognostic value of NUSAP1 in progression and expansion of glioblastoma multiforme
.
J Neurooncol
.
2018
Nov
;
140
(
2
):
199
208
.
[PubMed]
0167-594X
36.
Zhu
T
,
Xie
P
,
Gao
YF
,
Huang
MS
,
Li
X
,
Zhang
W
, et al
Nucleolar and spindle-associated protein 1 is a tumor grade correlated prognosis marker for glioma patients
.
CNS Neurosci Ther
.
2018
Mar
;
24
(
3
):
178
86
.
[PubMed]
1755-5930
37.
Pan
HW
,
Chou
HY
,
Liu
SH
,
Peng
SY
,
Liu
CL
,
Hsu
HC
.
Role of L2DTL, cell cycle-regulated nuclear and centrosome protein, in aggressive hepatocellular carcinoma
.
Cell Cycle
.
2006
Nov
;
5
(
22
):
2676
87
.
[PubMed]
1538-4101
38.
Ueki
T
,
Nishidate
T
,
Park
JH
,
Lin
ML
,
Shimo
A
,
Hirata
K
, et al
Involvement of elevated expression of multiple cell-cycle regulator, DTL/RAMP (denticleless/RA-regulated nuclear matrix associated protein), in the growth of breast cancer cells
.
Oncogene
.
2008
Sep
;
27
(
43
):
5672
83
.
[PubMed]
0950-9232
39.
Li
J
,
Ng
EK
,
Ng
YP
,
Wong
CY
,
Yu
J
,
Jin
H
, et al
Identification of retinoic acid-regulated nuclear matrix-associated protein as a novel regulator of gastric cancer
.
Br J Cancer
.
2009
Aug
;
101
(
4
):
691
8
.
[PubMed]
0007-0920
40.
Baraniskin
A
,
Birkenkamp-Demtroder
K
,
Maghnouj
A
,
Zöllner
H
,
Munding
J
,
Klein-Scory
S
, et al
MiR-30a-5p suppresses tumor growth in colon carcinoma by targeting DTL
.
Carcinogenesis
.
2012
Apr
;
33
(
4
):
732
9
.
[PubMed]
0143-3334
41.
Yang
L
,
Dai
J
,
Ma
M
,
Mao
L
,
Si
L
,
Cui
C
, et al
Identification of a functional polymorphism within the 3′-untranslated region of denticleless E3 ubiquitin protein ligase homolog associated with survival in acral melanoma
.
Eur J Cancer
.
2019
Sep
;
118
:
70
81
.
[PubMed]
0959-8049
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.