Epigenetic repression of microRNA-129-2 leads to overexpression of SOX4 in gastric cancer

doi:10.1016/j.bbrc.2010.03.121

Biochemical and Biophysical Research Communications

Volume 394, Issue 4, 16 April 2010, Pages 1047-1052

https://doi.org/10.1016/j.bbrc.2010.03.121 Get rights and content

Abstract

High levels of SOX4 expression have been found in a variety of human cancers, such as lung, brain and breast cancers. However, the expression of SOX4 in gastric tissues remains unknown. The SOX4 expression was detected using immunohistochemical staining and semi-quantitative RT-PCR, and our results showed that SOX4 was up-regulated in gastric cancer compared to benign gastric tissues. To further elucidate the molecular mechanisms underlying up-regulation of SOX4 in gastric cancers, we analyzed the expression of microRNA-129-2 (miR-129-2) gene, the epigenetic repression of which leads to overexpression of SOX4 in endometrial cancer. We found that up-regulation of SOX4 was inversely associated with the epigenetic silencing of miR-129-2 in gastric cancer, and restoration of miR-129-2 down-regulated SOX4 expression. We also found that inactivation of SOX4 by siRNA and restoration of miR-129-2 induced apoptosis in gastric cancer cells.

Introduction

The SOX4 gene maps to 6p22.3 and encodes a 47 kDa protein of the sex-determining region Y (SRY) box, or SOX, family [1], [2]. The SOX4 gene is highly conserved in vertebrates, there is 88% identity at the DNA level between Homo sapiens and Fugu rubripes in the NH₂-terminal domain [2]. It was reported that stable overexpression of SOX4 in the immortalized, nontransformed RWPE-1 prostate cell line enabled anchorage-independent growth and colony formation in soft agar [2]. Overexpression of SOX4 by retroviral insertional mutagenesis in genetically modified mouse strains results in a high incidence of myeloid leukemias and B- and T-cell lymphomas [3], [4], [5]. High levels of SOX4 expression have been reported in hepatic cancer cells, breast cancer, brain, lung, pancreatic, salivary gland, bladder cancer and ovarian cancers, suggesting a role of SOX4 in cancer [2], [6], [7], [8], [9], [10], [11].

In endometrial cancer, the aberrant expression of SOX4 is, in part, caused by epigenetic repression of miR-129-2. Here, we have confirmed SOX4 overexpression in gastric cancer patient tissues by semi-quantitative real-time PCR and immunohistochemistry. We also figured out that up-regulation of SOX4 was inversely associated with the epigenetic silencing of miR-129-2 in gastric cancer, and exogenous expression of miR-129-2 down-regulated SOX4 expression. We also explored the correlation between SOX4 expression status and clinical features.

Section snippets

Patients

Human gastric cancer samples were collected from surgical specimens from 70 patients with gastric cancer at Department of Surgery, Qingpu Branch of Zhongshan Hospital, Fudan University, China. Non-tumor samples from the macroscopic tumor margin were isolated at the same time and used as the matched adjacent non-neoplastic tissues (>5 cm). All the samples were divided into two parts. Tissue samples were collected, immediately snap frozen in liquid nitrogen, and stored at −80 °C until RNA

Expression profile of SOX4 in gastric lesions

Tissues from patients with gastric cancer and other gastric lesions were retrospectively identified from the Department of Pathology, Rui-jin Hospital. The 70 gastric cancers comprised 34 early cases and 36 advanced cases, the clinicopathologic characteristics were analyzed according to tumor size, histological grading and presence of nodal metastasis. Expression of SOX4 in normal gastric epithelium and carcinomas detected by immunohistochemistry were semiquantitated. Overall, expression of

Discussion

miRNAs are 16- to 25-nucleotide-long RNAs, able to bind complementary sequences in 3-untranslated regions (3′-UTR) of several target mRNAs to induce their degradation or translational repression. They are deemed to play a crucial role in the initiation and progression of human cancer [15]. In humans, SOX4 is up-regulated in hepatic cancer cells, breast cancer, colon, brain, lung, pancreatic, salivary gland, and ovarian cancers suggesting that SOX4 may play an important role in multiple tumor

References (20)

C.S. Moreno
The sex-determining region Y-Box 4 and homeobox C6 transcriptional networks in prostate cancer progression. Crosstalk with the Wnt, notch, and PI3K pathways
Am. J. Pathol.
(2010)
Y. Du et al.
Cooperating cancer-gene identification through oncogenic-retrovirus-induced insertional mutagenesis
Blood
(2005)
S.G. Ahn et al.
Identification of cDNAs for Sox-4, an HMG-Box protein, and a novel human homolog of yeast splicing factor SSF-1 differentially regulated during apoptosis induced by prostaglandin A2/delta12-PGJ2 in Hep3B cells
Biochem. Biophys. Res. Commun.
(1999)
H.F. Frierson et al.
Large scale molecular analysis identifies genes with altered expression in salivary adenoid cystic carcinoma
Am. J. Pathol.
(2002)
A. Mavropoulos et al.
Sox4b is a key player of pancreatic alpha cell differentiation in zebrafish
Dev. Biol.
(2005)
M. Cheung et al.
Roles of Sox4 in central nervous system development
Brain Res. Mol. Brain Res.
(2000)
P. Liu et al.
Sex-determining region Y box 4 is a transforming oncogene in human prostate cancer cells
Cancer Res.
(2006)
M.S. Shin et al.
High-throughput retroviral tagging for identification of genes involved in initiation and progression of mouse splenic marginal zone lymphomas
Cancer Res.
(2004)
Z. Li et al.
Insertional mutagenesis by replication-deficient retroviral vectors encoding the large T oncogene
Ann. NY Acad. Sci.
(2007)
J.D. Graham et al.
Regulation of the expression and activity by progestins of a member of the SOX gene family of transcriptional modulators
J. Mol. Endocrinol.
(1999)

There are more references available in the full text version of this article.

Cited by (143)

miR-129-2-3p inhibits colon cancer cell proliferation by down-regulating the expression of BZW1
2024, Arab Journal of Gastroenterology
MicroRNA (miRNA) is involved in diverse biological and physiological processes of tumors. Dysregulation of miRNA will induce a series of human diseases. miR-129-2-3p has vital effects in the pathogenesis of various tumors. However, the regulatory function of miR-129-2-3p in colon cancer remains to be clarified. This study investigated the role of miR-129-2-3p targeting BZW1 in proliferation, apoptosis, migration, and invasion of colon cancer.
Here, RT-qPCR was applied to measure the miR-129-2-3p levels in colon cancer tissues. The predicted targets of miR-129-2-3p were identified by bioinformatics and verified using luciferase reporter assay. The effects of miR-129-2-3p on colon cancer were detected by CCK-8, colony formation, transwell chamber test, wound healing, and flow cytometry assays. Finally, the influence of miR-129-2-3p on tumor growth was studied. Nude mice were xenografted with transfected Lovo cells by subcutaneous injection of 5 × 10⁵ cells in 100 µl. HE staining and TUNEL were used to assess metastasis ability.
miR-129-2-3p level in colon cancer tissue was significantly reduced. Furthermore, it was verified that BZW1 was a target of miR-129-2-3p, and its expression in colon cancer cells was inhibited by miR-129-2-3p. Additionally, miR-129-2-3p inhibited colon cancer cell proliferation, colony formation, mobility ability and tumor growth, and promoted cell apoptosis by targeting BZW1. miR-129-2-3p overexpression in tumor xenografts in vivo decreased BZW1 expression, and suppressed tumor growth.
Collectively, these findings indicated that miR-129-2-3p exerts a suppressive role in colon cancer cells by directly targeting BZW1, and may have significant therapeutic implications for patients with colon cancer.
The role of SOX family transcription factors in gastric cancer
2021, International Journal of Biological Macromolecules
Gastric cancer (GC) is a leading cause of death worldwide. GC is the third-most common cause of cancer-related death after lung and colorectal cancer. It is also the fifth-most commonly diagnosed cancer. Accumulating evidence has revealed the role of signaling networks in GC progression. Identification of these molecular pathways can provide new insight into therapeutic approaches for GC. Several molecular factors involved in GC can play both onco-suppressor and oncogene roles. Sex-determining region Y (Sry)-box-containing (SOX) family members are transcription factors with a well-known role in cancer. SOX proteins can bind to DNA to regulate cellular pathways via a highly conserved domain known as high mobility group (HMG). In the present review, the roles of SOX proteins in the progression and/or inhibition of GC are discussed. The dual role of SOX proteins as tumor-promoting and tumor-suppressing factors is highlighted. SOX members can affect upstream mediators (microRNAs, long non-coding RNAs and NF-κB) and down-stream mediators (FAK, HIF-1α, CDX2 and PTEN) in GC. The possible role of anti-tumor compounds to target SOX pathway members in GC therapy is described. Moreover, SOX proteins may be used as diagnostic or prognostic biomarkers in GC.
Crosstalk between long non-coding RNA DLX6-AS1, microRNAs and signaling pathways: A pivotal molecular mechanism in human cancers
2021, Gene
Long non-coding RNAs (lncRNAs) are a type of non-protein coding RNA, which have been found to play multiple roles in various molecular and cellular processes by epigenetic regulation of gene expression at post transcriptional levels. LncRNAs may act either as an oncogene or as a tumor suppressor gene in different cancers. Aberrant expression and dysregulation of lncRNAs has been correlated with cancer development and tumor growth via several different signaling pathways. Therefore, lncRNAs could serve as diagnostic biomarkers and as therapeutic targetes in many human cancers. Previous studies have reported that dysregulated expression of the lncRNA called DLX6-AS1 in various cancer types, such as lung, colorectal, bladder, ovarian, hepatocellular, pancreatic and gastric. DLX6-AS1 plays an important role in tumorigenesis by affecting cell proliferation, migration, invasion, EMT, and apoptosis. DLX6-AS1 exerts these regulatory effects by interfering with various microRNA axes and signaling pathways including, Wnt/βcatenin, Notch, P13/AKT/mTOR, and STAT3. This review focuses on the possible mechanisms by which DLX6-AS1 regulates tumor initiation and progression. Accordingly, DLX6-AS1 may act as a novel potential biomarker for cancer diagnosis or therapy in future.
SOX4: Epigenetic regulation and role in tumorigenesis
2020, Seminars in Cancer Biology
Citation Excerpt :
Similarly, Zhang and colleagues demonstrated a tumor suppressor role for miR-129-5p in chondrosarcoma [91]. MiR-129-2 was found to be epigenetically silenced in endometrial, gastric, esophageal, and hepatocellular carcinoma, leading to increases in SOX4 expression and cell proliferation [92–95]. In ovarian cancer, miR-138 and the miR-212/132 cluster were shown to function as tumor suppressors through targeting SOX4 [96,97].
Sex-determining region Y-related (SRY) high-mobility group box 4 (SOX4) is a member of the group C subfamily of SOX transcription factors and promotes tumorigenesis by endowing cancer cells with survival, migratory, and invasive capacities. Emerging evidence has highlighted an unequivocal role for this transcription factor in mediating various signaling pathways involved in tumorigenesis, epithelial-to-mesenchymal transition (EMT), and tumor progression. During the last decade, numerous studies have highlighted the epigenetic interplay between SOX4-targeting microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and SOX4 and the subsequent modulation of tumorigenesis, invasion and metastasis. In this review, we summarize the current state of knowledge about the role of SOX4 in cancer development and progression, the epigenetic regulation of SOX4, and the potential utilization of SOX4 as a diagnostic and prognostic biomarker and its depletion as a therapeutic target.
SRY-related high-mobility-group box 4: Crucial regulators of the EMT in cancer
2020, Seminars in Cancer Biology
Citation Excerpt :
In adult tissues, Sox4 is expressed in specific cell types, including mouse ovaries and Pre-B/T lymphocytes of the testes, breast and thymus [14,15]. In addition, many studies have shown that Sox4 is abnormally expressed in many cancer cells and tumor tissues, such as breast [16], prostate [17], lung [18], liver [19], endometrium [20], colon [21], bladder [22] and malignant melanoma [23]; moreover, Sox4 expression has been shown to be closely related to the occurrence and development of cancer. These studies suggest that Sox4 may serve as prognostic marker or a potential therapeutic target for tumors.
The epithelial-mesenchymal transition (EMT) is a process of cell transformation under certain physiological and pathological states in which epithelial cells are transformed into mesenchymal cells with fibroblast-like properties, which confers upon them the increased invasion and migration capabilities of cancer cells. Previous studies have demonstrated that SRY-related high-mobility-group box 4 (Sox4) protein coordinates EMT-related pathways and EMT-related transcription factors, thereby regulating the EMT process. The focus of this review is to evaluate recent advances regarding the role of Sox4 protein in the cancer EMT. First, we provide an overview of the general background of Sox4 (structure and function) and the EMT in cancer. Next, we introduce the interactions between Sox4 protein and various factors during cancer EMT. Finally, we suggest directions for future investigations. In general, the information compiled in this paper should serve as a comprehensive repository of information on the subject matter and contribute to the design of other research and future efforts to develop therapeutic strategies that target the Sox4 protein.
The role of SOX family members in solid tumours and metastasis
2020, Seminars in Cancer Biology
Citation Excerpt :
The difference could be explained as follows: promoters of different genes can be targeted in different situations [301]. The up-regulation of SOX4, SOX9 or SOX17 was frequently associated with a more severe case of gastric cancer [302–305], while SOX7 appears to have suppressive effects [306]. In contrast, another study on a mouse model reported that the down-regulation of SOX17 contributes to the development of gastric cancer [307].
Cancer is a heavy burden for humans across the world with high morbidity and mortality. Transcription factors including sex determining region Y (SRY)-related high-mobility group (HMG) box (SOX) proteins are thought to be involved in the regulation of specific biological processes. The deregulation of gene expression programs can lead to cancer development. Here, we review the role of the SOX family in breast cancer, prostate cancer, renal cell carcinoma, thyroid cancer, brain tumours, gastrointestinal and lung tumours as well as the entailing therapeutic implications. The SOX family consists of more than 20 members that mediate DNA binding by the HMG domain and have regulatory functions in development, cell-fate decision, and differentiation. SOX2, SOX4, SOX5, SOX8, SOX9, and SOX18 are up-regulated in different cancer types and have been found to be associated with poor prognosis, while the up-regulation of SOX11 and SOX30 appears to be favourable for the outcome in other cancer types. SOX2, SOX4, SOX5 and other SOX members are involved in tumorigenesis, e.g. SOX2 is markedly up-regulated in chemotherapy resistant cells. The SoxF family (SOX7, SOX17, SOX18) plays an important role in angio- and lymphangiogenesis, with SOX18 seemingly being an attractive target for anti-angiogenic therapy and the treatment of metastatic disease in cancer. In summary, SOX transcription factors play an important role in cancer progression, including tumorigenesis, changes in the tumour microenvironment, and metastasis. Certain SOX proteins are potential molecular markers for cancer prognosis and putative potential therapeutic targets, but further investigations are required to understand their physiological functions.

View all citing articles on Scopus

View full text

Epigenetic repression of microRNA-129-2 leads to overexpression of SOX4 in gastric cancer

Abstract

Introduction

Section snippets

Patients

Expression profile of SOX4 in gastric lesions

Discussion

Am. J. Pathol.

Blood

Biochem. Biophys. Res. Commun.

Am. J. Pathol.

Dev. Biol.

Brain Res. Mol. Brain Res.

Sex-determining region Y box 4 is a transforming oncogene in human prostate cancer cells

Cancer Res.

High-throughput retroviral tagging for identification of genes involved in initiation and progression of mouse splenic marginal zone lymphomas

Cancer Res.

Insertional mutagenesis by replication-deficient retroviral vectors encoding the large T oncogene

Ann. NY Acad. Sci.

Regulation of the expression and activity by progestins of a member of the SOX gene family of transcriptional modulators

J. Mol. Endocrinol.