• Molecules and Cells
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• v.45 no.6
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• pp.376-387
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• 2022

Extracellular vesicles (EVs) play an essential role in the communication between cells and the tumor microenvironment. However, the effect of tumor-derived EVs on the growth and metastasis of lung adenocarcinoma (LUAD) remains to be explored. This study aimed to elucidate the role of miR-153-3p-EVs in the invasion and migration capabilities of LUAD cells and explore its mechanism through in vivo and in vitro experiments. We found that miR-153-3p was specifically and highly expressed in LUAD and its secreted EVs. Furthermore, the expression of BANCR was negatively regulated by miR-153-3p and identified as a target gene of miR-153-3p using luciferase reporter assays. Through further investigation, we found that the downregulation of BANCR activates the PI3K/AKT pathway and accelerates the process of epithelial-mesenchymal transition (EMT), which ultimately leads to the aggravation of LUAD. The orthotopic xenograft mouse model was established to illustrate the effect of miR-153-3p-EVs on LUAD. Animal studies showed that miR-153-3p-EVs accelerated tumor growth in mice. Besides, we found that miR-153-3p-EVs could damage the respiratory ability of mice and produce a mass of inflammatory cells around the lung tissue of mice. Nevertheless, antagomir-153-3p treatment could inhibit the deterioration of respiratory function and inhibit the growth of lung tumors in mice. In conclusion, our study reveals the potential molecular mechanism of miR-153-3p-EVs in the development of LUAD and provides a potential strategy for the treatment of LUAD.

• Molecules and Cells
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• v.45 no.12
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• pp.935-949
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• 2022

Liver cancer has a high prevalence, with majority of the cases presenting as hepatocellular carcinoma (HCC). The prognosis of metastatic HCC has hardly improved over the past decade, highlighting the necessity for liver cancer research. Studies have reported the ability of the KiSS1 gene to inhibit the growth or metastasis of liver cancer, but contradictory research results are also emerging. We, therefore, sought to investigate the effects of KiSS1 on growth and migration in human HCC cells. HepG2 human HCC cells were infected with lentivirus particles containing KiSS1. The overexpression of KiSS1 resulted in an increased proliferation rate of HCC cells. Quantitative polymerase chain reaction and immunoblotting revealed increased Akt activity, and downregulation of the G1/S phase cell cycle inhibitors. A significant increase in tumor spheroid formation with upregulation of β-catenin and CD133 was also observed. KiSS1 overexpression promoted the migratory, invasive ability, and metastatic capacity of the hepatocarcinoma cell line, and these effects were associated with changes in the expressions of epithelial mesenchymal transition (EMT)- related genes such as E-cadherin, N-cadherin, and slug. KiSS1 overexpression also resulted in dramatically increased tumor growth in the xenograft mouse model, and upregulation of proliferating cell nuclear antigen (PCNA) and Ki-67 in the HCC tumors. Furthermore, KiSS1 increased the angiogenic capacity by upregulation of the vascular endothelial growth factor A (VEGF-A) and CD31. Based on these observations, we infer that KiSS1 not only induces HCC proliferation, but also increases the metastatic potential by increasing the migratory ability and angiogenic capacity.

• BMB Reports
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• v.48 no.9
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• pp.525-530
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• 2015

Activation of the Wnt/β-catenin pathway plays a pathogenic role in age-related macular degeneration (AMD) and is thus a potential target for the development of therapeutics for this disease. Here, we demonstrated that Wnt5a antagonized β-catenin response transcription (CRT) induced with Wnt3a by promoting β-catenin phosphorylation at Ser33/Ser37/Thr41 and its subsequent degradation in human retinal pigment epithelial (RPE) cells. Wnt5a decreased the levels of vascular endothelial growth factor (VEGF), tumor necrosis factor-α(TNF-α), and nuclear factor-κB (NF-κB), which was up-regulated by Wnt3a. Furthermore, Wnt5a increased E-cadherin expression and decreased cell migration by down-regulating Snail expression, thereby abrogating the Wnt3a-induced epithelial-mesenchymal transition (EMT) in human RPE cells. Our findings suggest that Wnt5a suppresses the pathogenic effects of canonical Wnt signaling in human RPE cells by promoting β-catenin phosphorylation and degradation. Therefore, Wnt5a has significant therapeutic potential for the treatment of AMD. [BMB Reports 2015; 48(9): 525-530]

• Journal of Life Science
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• v.27 no.11
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• pp.1245-1255
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• 2017

Most cancer cells produce ATP predominantly through glycolysis instead of through mitochondrial oxidative phosphorylation, even in the presence of oxygen. The phenomenon is termed the Warburg effect, or the glycolytic switch, and it is thought to increase the availability of biosynthetic precursors for cell proliferation. EMTs have critical roles in the initiation of the invasion and metastasis of cancer cells. The glycolytic switch and EMT are important for tumor development and progression; however, their correlation with tumor progression is largely unknown. The Snail transcription factor is a major factor involved in EMT. The Snail expression is regulated by distal-less homeobox 2 (Dlx-2), a homeodomain transcription factor that is involved in embryonic and tumor development. The Dlx-2/Snail cascade is involved in Wnt-induced EMTs and the glycolytic switch. This study showed that in response to Wnt signaling, the Dlx-2/Snail cascade induces the expression of PFKFB2, which is a glycolytic enzyme that synthesizes and degrades fructose 2, 6-bisphosphate (F2,6BP). It also showed that PFKFB2 shRNA prevents Wnt-induced EMTs in the breast-tumor cell line MCF-7. The prevention indicated that glycolysis is linked to Wnt-induced EMT. Additionally, this study showed PFKFB2 shRNA suppresses in vivo tumor metastasis and growth. Finally, it showed the PFKFB2 expression is higher in breast, colon and ovarian cancer tissues than in matched normal tissues regardless of the cancers' stages. The results demonstrated that PFKFB2 is an important regulator of EMTs and metastases induced by the Wnt, Dlx-2 and Snail factors.

• Journal of Life Science
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• v.29 no.1
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• pp.9-17
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• 2019

As tumors develop, they encounter microenvironmental stress, such as hypoxia and glucose depletion, due to poor vascular function, thereby leading to necrosis, which is observed in solid tumors. Necrotic cells are known to release cellular cytoplasmic contents, such as high mobility group box 1 (HMGB1), into the extracellular space. The release of HMGB1, a proinflammatory and tumor-promoting cytokine, plays an important role in promoting inflammation and metabolism during tumor development. Recently, HMGB1 was shown to induce the epithelial-mesenchymal transition (EMT) and metastasis. However, the underlying mechanism of the HMGB1-induced EMT, invasion, and metastasis is unclear. In this study, we showed that noninvasive breast cancer cells MCF-7 formed tightly packed, rounded spheroids and that the cells in the inner regions of a multicellular tumor spheroid (MTS), an in vitro model of a solid tumor, led to necrosis due to an insufficient supply of O2 and glucose. In addition, after 7 d of MTS culture, the EMT was induced via the transcription factor Snail. We also showed that HMGB1 receptors, including RAGE, TLR2, and TLR4, were induced by MTS culture. RAGE, TLR2, and TLR4 shRNA inhibited MTS growth, supporting the idea that RAGE/TLR2/TLR4 play critical roles in MTS growth. They also prevented MTS culture-induced Snail expression, pointing to RAGE/TLR2/TLR4-dependent Snail expression. RAGE, TLR2, and TLR4 shRNA suppressed the MTS-induced EMT. In human cancer tissues, high levels of RAGE, TLR2, and TLR4 were detected. These findings demonstrated that the HMGB-RAGE/TLR2/TLR4-Snail axis played a crucial role in the growth of the MTS and MTS culture-induced EMT.

• BMB Reports
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• v.52 no.3
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• pp.196-201
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• 2019

The Alu element, the most abundant transposable element, is transcribed to Alu RNA. We hypothesized that the PIWI protein regulates the expression of Alu RNA in retinal pigment epithelial (RPE) cells, where accumulated Alu RNA leads to macular degeneration. Alu transcription was induced in RPE cells treated with $H_2O_2$. At an early stage of oxidative stress, PIWIL4 was translocated into the nucleus; however, subsequently it was sequestered into cytoplasmic stress granules, resulting in the accumulation of Alu RNA. An elevated amount of Alu RNA was positively correlated with the disruption of the epithelial features of RPE via induction of mesenchymal transition. Therefore, we suggest that oxidative stress causes Alu RNA accumulation via PIWIL4 sequestration into the cytoplasmic stress granules.

• Tuberculosis and Respiratory Diseases
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• v.79 no.3
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• pp.143-152
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• 2016

Background: Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal lung disease characterized by the accumulation of excessive fibroblasts and myofibroblasts in the extracellular matrix. The transforming growth factor ${\beta}1$ (TGF-${\beta}1$)-induced epithelial-to-mesenchymal transition (EMT) is thought to be a possible source of fibroblasts/myofibroblasts in IPF lungs. We have previously reported that apolipoprotein A1 (ApoA1) has anti-fibrotic activity in experimental lung fibrosis. In this study, we determine whether ApoA1 modulates TGF-${\beta}1$-induced EMT in experimental lung fibrosis and clarify its mechanism of action. Methods: The A549 alveolar epithelial cell line was treated with TGF-${\beta}1$ with or without ApoA1. Morphological changes and expression of EMT-related markers, including E-cadherin, N-cadherin, and ${\alpha}$-smooth muscle actin were evaluated. Expressions of Smad and non-Smad mediators and TGF-${\beta}1$ receptor type 1 ($T{\beta}RI$) and type 2 ($T{\beta}RII$) were measured. The silica-induced lung fibrosis model was established using ApoA1 overexpressing transgenic mice. Results: TGF-${\beta}1$-treated A549 cells were changed to the mesenchymal morphology with less E-cadherin and more N-cadherin expression. The addition of ApoA1 inhibited the TGF-${\beta}1$-induced change of the EMT phenotype. ApoA1 inhibited the TGF-${\beta}1$-induced increase in the phosphorylation of Smad2 and 3 as well as that of ERK and p38 mitogen-activated protein kinase mediators. In addition, ApoA1 reduced the TGF-${\beta}1$-induced increase in $T{\beta}RI$ and $T{\beta}RII$ expression. In a mouse model of silica-induced lung fibrosis, ApoA1 overexpression reduced the silica-mediated effects, which were increased N-cadherin and decreased E-cadherin expression in the alveolar epithelium. Conclusion: Our data demonstrate that ApoA1 inhibits TGF-${\beta}1$-induced EMT in experimental lung fibrosis.

• Journal of Life Science
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• v.29 no.8
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• pp.904-915
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• 2019

Prostate cancer (PCa) is one of the most metastatic tumor. Although hormone therapy or surgical castration is mostly conducted to treat PCa, it has a lot of side effects. Recently, many researchers have been exploring the tumor microenvironment to remedy these circumstances. Immune cells, especially macrophages, are an important composition of the tumor microenvironment. Under normal conditions, macrophages exhibit mild tumoricidal activity against tumors. However, once activated by interferon gamma or lipopolysaccharides, macrophages can kill cancer cells directly or indirectly by secreting cytokines and chemokines. In this study, murine macrophage RAW 264.7 cells were treated with Phellinus linteus extract. To analyze their pro-inflammatory phenotype, we were used several assays such as a real-time polymerase chain reaction, an enzyme-linked immunosorbent and nitric oxide assay. Prostate cancer cells were treated with the RAW 264.7-conditioned media, which was identified as a pro-inflammatory nature, for 48 h, and the expression of epithelial-mesenchymal transition (EMT)-related genes was determined. Not only N-cadherin, Snail, Twist, Slug, and Cadherin 11, which are mechenchymal-related proteins, were decrease, but epithelial marker of E-cadherin was increased. In addition, the mRNA level of vimentin, ccl2, and vegfa were decreased, as the EMT is closely related to the migration and invasion of cancer cells. In conclusion, the RAW 264.7-conditioned media stimulated with P. linteus extract inhibited migration and invasion and regulated the EMT pathway in human prostate cancer cells.

• BMB Reports
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• v.55 no.2
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• pp.87-91
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• 2022

Aurora kinase is a family of serine/threonine kinases intimately associated with mitotic progression and the development of human cancers. Studies have shown that aurora kinases are important for the protein kinase C (PKC)-induced invasion of colon cancer cells. Recent studies have shown that aurora kinase A promotes distant metastasis by inducing epithelial-to-mesenchymal transition (EMT) in colon cancer cells. However, the role of aurora kinase A in colon cancer metastasis remains unclear. In this study, we investigated the effects of aurora kinase A on PKC-induced cell invasion, migration, and EMT in human SW480 colon cancer cells. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) changed the expression levels of EMT markers, increasing α-SMA, vimentin, and MMP-9 expression and decreasing E-cadherin expression, with changes in cell morphology. TPA treatment induced EMT in a PKC-dependent manner. Moreover, the inhibition of aurora kinase A by siRNAs and inhibitors (reversine and VX-680) suppressed TPA-induced cell invasion, migration, and EMT in SW480 human colon cells. Inhibition of aurora kinase A blocked TPA-induced vimentin and MMP-9 expression, and decreased E-cadherin expression. Furthermore, the knockdown of aurora kinase A decreased the transcriptional activity of NF-κB and AP-1 in PKC-stimulated SW480 cells. These findings indicate that aurora kinase A induces migration and invasion by inducing EMT in SW480 colon cancer cells. To the best of our knowledge, this is the first study that showed aurora kinase A is a key molecule in PKC-induced metastasis in colon cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1037-1047
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• 2016

HOX transcription factors are evolutionarily conserved in many different species and are involved in important cellular processes such as morphogenesis, differentiation, and proliferation. They have also recently been implicated in carcinogenesis, but their precise role in cancer, especially in cervical cancer (CC), remains unclear. In this work, using microarray assays followed by the quantitative polymerase chain reaction (qPCR), we found that the expression of 25 HOX genes was downregulated in CC derived cell lines compared with non-tumorigenic keratinocytes. In particular, the expression of HOXA9 was observed as down-modulated in CC-derived cell lines. The expression of HOXA9 has not been previously reported in CC, or in normal keratinocytes of the cervix. We found that normal CC from women without cervical lesions express HOXA9; in contrast, CC cell lines and samples of biopsies from women with CC showed significantly diminished HOXA9 expression. Furthermore, we found that methylation at the first exon of HOXA9 could play an important role in modulating the expression of this gene. Exogenous restoration of HOXA9 expression in CC cell lines decreased cell proliferation and migration, and induced an epithelial-like phenotype. Interestingly, the silencing of human papilloma virus (HPV) E6 and E7 oncogenes induced expression of HOXA9. In conclusion, controlling HOXA9 expression appears to be a necessary step during CC development. Further studies are needed to delineate the role of HOXA9 during malignant progression and to afford more insights into the relationship between downmodulation of HOXA9 and viral HPV oncoprotein expression during cercical cancer development.