Expression Promotes Cell Growth Research Articles

CircRNA-SFMBT2 orchestrates ERα activation to drive tamoxifen resistance in breast cancer cells

Dysregulated ERα signaling is responsible for endocrine resistance and eventual relapse in patients with estrogen receptor-positive (ER+) breast cancer. Thus, identifying novel ERα regulators is necessary to fully understand the mechanisms of endocrine resistance. Here, we identified circRNA-SFMBT2 to be highly expressed in ER+ breast cancer cells in comparison to ER− cells and found that high circRNA-SFMBT2 levels were related to larger tumor size and poor prognosis in patients with ER+ breast cancer. In vitro and in vivo experiments confirmed that the circRNA-SFMBT2 level was positively correlated with the ERα protein level, implying a regulatory role for circRNA-SFMBT2 in ERα signaling. Moreover, we found that circRNA-SFMBT2 biogenesis could be facilitated via RNA-binding protein quaking (QKI), and biologically elevated circRNA-SFMBT2 expression promoted cell growth and tamoxifen resistance in ER+ breast cancer. Mechanistically, circRNA-SFMBT2 exhibits a specific tertiary structure that endows it with a high binding affinity for ERα and allows it to interact with the AF2 and DBD domains of ERα, enforcing recruitment of RNF181 to the AF1 domain of ERα. Furthermore, the circRNA-SFMBT2/RNF181 axis differentially regulated K48-linked and K63-linked ubiquitination of ERα to enhance ERα stability, resulting in increased expression of ERα target genes and tumor progression. In summary, circRNA-SFMBT2 is an important regulator of ERα signaling, and antagonizing circRNA-SFMBT2 expression may constitute a potential therapeutic strategy for breast cancer.

GID2 Interacts With CDKN3 and Regulates Pancreatic Cancer Growth and Apoptosis

Dysregulation of deubiquitinase or ubiquitinase-mediated protein expression contributes to various diseases, including cancer. In the present study, we identified GID2, a subunit of the glucose-induced degradation-deficient (GID) complex that functions as an E3 ubiquitin ligase, as a potential key candidate gene in pancreatic cancer (PC) progression. The functional role and potential mechanism of GID2 in PC progression were investigated. Integrated bioinformatics analysis was performed to identify differentially expressed genes in PC based on the Gene Expression Profiling Interactive Analysis data sets. We found that GID2 was upregulated in PC tissues and that a high level of GID2 expression in clinical PC samples was positively associated with tumor stage and poor survival. Functional assays elucidated that GID2 expression promoted cell growth in vitro and accelerated tumor growth in vivo. GID2 knockdown effectively attenuated the malignant behaviors of PC cells and tumor formation. Furthermore, the protein network that interacted with the GID2 protein was constructed based on the GeneMANIA website. Cyclin-dependent kinase inhibitor 3 (CDKN3), a cell cycle regulator, was identified as a potential target of the GID2 protein. We revealed that GID2 positively regulated CDKN3 expression and inhibited CDKN3 ubiquitination. Furthermore, CDKN3 downregulation reversed the promoting effects of GID2 on PC progression. Therefore, the present study demonstrated that GID2 might regulate PC progression by maintaining the stability of the CDKN3 protein. These findings highlight the potential roles of the GID2/CDKN3 axis as a potential therapeutic target in PC.

Correction to Expression of Concern on: Reduced CTGF expression promotes cell growth, migration, and invasion in nasopharyngeal carcinoma

[This corrects the article DOI: 10.1371/journal.pone.0231520.].

Expression of concern: Reduced CTGF expression promotes cell growth, migration, and invasion in nasopharyngeal carcinoma.

Expression of concern: Reduced CTGF expression promotes cell growth, migration, and invasion in nasopharyngeal carcinoma.

MiR-639 Expression Is Silenced by DNMT3A-Mediated Hypermethylation and Functions as a Tumor Suppressor in Liver Cancer Cells.

Emerging evidence has indicated that abnormal methylation of DNA contributes to hepatocarcinogenesis. However, the regulatory mechanisms are not well known. Here, we revealed that microRNA-639 (miR-639) expression is downregulated in liver cancer tissues and cells. The repression of miR-639 expression was attributed to hypermethylation in its promoter region, and DNA methyltransferase (DNMT3A) was found to mediate this hypermethylation. Repression of miR-639 expression promoted cell growth and migration/invasion invitro and the growth of tumors in xenograft mouse models. Furthermore, miR-639 bound to the 3' UTR of both MYST2 and ZEB1 and suppressed their expression. MYST2 promoted the growth of liver cancer cells and ZEB1 facilitated the migration/invasion of liver cancer cells. Ectopic expression of MYST2 and ZEB1 counteracted the repression of malignancy induced by miR-639, which coincided with the reciprocal correlation between miR-639 and MYST2 and ZEB1 expression in clinical hepatocellular carcinoma (HCC) tissues. Thus, DNMT3A-mediated hypermethylation suppressed miR-639 expression, derepressing the expression of MSYT2 and ZEB1, which promoted tumorigenesis of liver cancer. These findings may shed light on the mechanism of abnormal expression of miRNAs involved in the malignancy of liver cancer and provide new biomarkers for liver cancer.

LncRNA CASC9 interacts with CPSF3 to regulate TGF-\u03b2 signaling in colorectal cancer

BackgroundColorectal cancer (CRC) is the third most frequent cancer and the second leading cause of cancer-related death worldwide. Increasing evidence indicates that the deregulation of long noncoding RNAs (lncRNAs) contributes to tumor initiation and progression; however, little is known about the biological role of cancer susceptibility candidate 9 (CASC9) in CRC.MethodsNovel lncRNAs potentially involved in CRC tumorigenesis were identified from datasets downloaded from The Cancer LncRNome Atlas and The Atlas of Noncoding RNAs in Cancer. The CRC cell lines HCT-116, HCT-116 p53−/−, SW620, SW480, HT-29, LoVo, LS-174T, and RKO were used. Colony-formation, MTS, cell-cycle, apoptosis, and in-vivo tumorigenesis assays were used to determine the role of CASC9 in CRC cell growth in vitro and in vivo. Potential interaction between CASC9 and cleavage and polyadenylation specificity factor subunit 3 (CPSF3) was evaluated using RNA immunoprecipitation and RNA-protein pull-down assays. RNA-sequencing was performed to analyze gene expression following CASC9 knockdown. RT-qPCR, western blotting, and mRNA decay assays were performed to study the mechanisms involved.ResultsCASC9 was frequently upregulated in CRC, which was correlated with advanced TNM stage, and higher CASC9 levels were associated with poor patient outcomes. Knockdown of CASC9 inhibited growth and promoted apoptosis in CRC cells, whereas ectopic CASC9 expression promoted cell growth in vitro and in vivo. We demonstrated that CPSF3 is a CASC9-interacting protein, and knockdown of CPSF3 mimicked the effects of CASC9 knockdown in CRC cells. Furthermore, we found that CASC9 exerts its oncogenic activity by modulating TGFβ2 mRNA stability and upregulating the levels of TGFβ2 and TERT, resulting in an increase in phosphorylated SMAD3 and activation of TGF-β signaling, and enhanced TERT complex function in CRC cells. Finally, CPSF3 was significantly upregulated in CRC tissues as compared with adjacent or non-adjacent normal colon tissues, and CASC9, CPSF3, and TGFβ2 levels in human CRC tissues were positively correlated.ConclusionsCASC9 is a promising prognostic predictor for patients with CRC and the CASC9-CPSF3-TGFβ2 axis is a potential therapeutic target for CRC treatment.

Increased SPK1 expression promotes cell growth by activating the ERK1/2 signaling in non-small-cell lung cancer.

Lung cancer remains the leading cause of cancer-associated mortality in China and the world. Increasing numbers of studies have reported that sphingosine kinase 1 (SPK1) is frequently highly expressed in tumors of various origins, including lung cancer, and its high expression contributes toward tumor progression. However, the clinical significance of SPK1 and its role in the growth and metastasis of non-small-cell lung cancer (NSCLC) remain unclear. In the present study, we found that SPK1 expression was expressed highly in NSCLC tissues and cell lines. Knockdown of SPK1 suppressed cell growth, proliferation, migration, and invasion and increased apoptosis. Moreover, knocking down SPK1 expression inhibited the growth of tumors in nude mice. Mechanistically, silencing the expression of SPK1 inhibited the expression of p-extracellular signal-regulated kinase (ERK). Moreover, the ERK-specific inhibitor U0126 suppressed the expression of the epithelial-mesenchymal transition of lung cancer cells. Together, our findings indicated that SPK1 enhanced tumor growth in lung cancer and induced metastasis by activating the ERK1/2 signaling pathway, indicating its potential application in NSCLC diagnosis and therapy.

Reduced Klotho expression contributes to poor survival rates in human patients with ovarian cancer, and overexpression of Klotho inhibits the progression of ovarian cancer partly via the inhibition of systemic inflammation in nude mice.

Klotho is a recently discovered anti‑aging gene, which has been reported as a tumor suppressor in numerous human malignancies; however, the role of Klotho in human ovarian cancer remains to be elucidated. The aim of the present study was to detect the expression of Klotho and evaluate its association with the progression of human ovarian cancer. A clinical follow‑up study of 120patients with ovarian cancer and 78normal controls was conducted. The expression levels of Klotho were determined by western blotting and immunohistochemistry. The results demonstrated that high Klotho expression levels were detected in all normal controls, whereas the positive rate of Klotho was 61.6% in the ovarian cancer group, which was significantly decreased compared with in the control group (P<0.01). Furthermore, reduced Klotho expression was significantly correlated with decreased survival rates in patients with ovarian cancer (P=0.025). Subsequently, Klotho levels were detected in seven human ovarian cancer cell lines by western blotting. The results demonstrated that the highest levels of Klotho were detected in CaOV3 cells, medium levels of Klotho were detected in CaOV4 and SKOV‑3 cells, and almost no Klotho was detected in the other four cell lines: OVCA432, OVCAR‑5, OVCAR‑8 and A2780 cells. The association between Klotho levels and cell proliferation was determined by MTT assay, and the results indicated that higher levels of Klotho inhibited the proliferation of A2780 and OVCAR‑5 cells, whereas reduced Klotho expression promoted cell growth of CaOV3 and SKOV‑3 cells. In addition, the plasma levels of inflammatory cytokines in tumor‑bearing mice and normal control mice were detected by enzyme‑linked immunosorbent assay, and plasma interleukin (IL)‑6 and IL‑1β levels were elevated in all tumor‑bearing mice. Notably, the mRNA expression levels of IL‑6 were significantly higher in the liver, ovaries and kidneys of Klotho‑/‑ mice compared with in wild type mice (P<0.01), thus indicating that aberrant Klotho expression may contribute to systemic inflammation in Klotho‑/‑ mice. Finally, the invivo antitumor role of aberrant Klotho expression was determined in a nude mice model. A2780 cells were transfected with pCMV6‑Klotho and the stably transfected cells were screened; the mice were injected with the stably transfected cells. The results indicated that tumor volume and tumor weight were significantly decreased in the pCMV6‑Klotho group compared with in the pCMV6 vector group (P<0.01). These findings suggest that overexpression of Klotho may suppress tumor growth in animal models. In conclusion, Klotho was demonstrated to act as a potent tumor suppressor in human ovarian cancer cells. Reduced Klotho expression was detected in the specimens of patients with ovarian cancer, and overexpression of Klotho significantly inhibited cell proliferation of human ovarian cancer cells. Therefore, Klotho may be considered a useful key target for the molecular therapy of human ovarian cancer.

Reduced PDCD4 Expression Promotes Cell Growth Through PI3K/Akt Signaling in Non-Small Cell Lung Cancer.

It is largely recognized that PDCD4 is frequently lost in tumors of various origins, including lung cancer, and its loss contributes to tumor progression. However, its role and molecular mechanism remain largely unexplored in non-small cell lung cancer (NSCLC). In this study, downregulated PDCD4 mRNA expression was found in NSCLC tissues compared to their corresponding paracarcinoma tissues and distal paracarcinoma tissues. Induced expression of PDCD4 inhibited cell growth and proliferation and cell cycle transition in vitro. Conversely, knocking down PDCD4 expression promoted cell growth and proliferation. Mechanistically, PDCD4 inactivated PI3K/Akt signaling and its downstream cell cycle factors CCND1 and CDK4 to regulate cell growth in NSCLC. Additionally, PI3K-specific inhibitor Ly294002 suppressed the expression of pPI3K (Tyr458), pAkt (Ser473), CCND1, and CDK4 in PC9-shPDCD4 and A549-shPDCD4 cells. Furthermore, Akt-specific inhibitor MK2206 inhibited the expression of pAkt (Ser473), CCND1, and CDK4 in PC9-shPDCD4 and A549-shPDCD4 cells. Taken together, our study provides evidence that PDCD4 inhibits cell growth through PI3K/Akt signaling in NSCLC and may be a potential therapeutic target for NSCLC.

An increase in integrin-linked kinase non-canonically confers NF-κB-mediated growth advantages to gastric cancer cells by activating ERK1/2.

BackgroundIncreased activity or expression of integrin-linked kinase (ILK), which regulates cell adhesion, migration, and proliferation, leads to oncogenesis. We identified the molecular basis for the regulation of ILK and its alternative role in conferring ERK1/2/NF-κB-mediated growth advantages to gastric cancer cells.ResultsInhibiting ILK with short hairpin RNA or T315, a putative ILK inhibitor, abolished NF-κB-mediated the growth in the human gastric cancer cells AGS, SNU-1, MKN45, and GES-1. ILK stimulated Ras activity to activate the c-Raf/MEK1/2/ERK1/2/ribosomal S6 kinase/inhibitor of κBα/NF-κB signaling by facilitating the formation of the IQ motif-containing GTPase-activating protein 1 (IQGAP1)–Ras complex. Forced enzymatic ILK expression promoted cell growth by facilitating ERK1/2/NF-κB signaling. PI3K activation or decreased PTEN expression prolonged ERK1/2 activation by protecting ILK from proteasome-mediated degradation. C-terminus of heat shock cognate 70 interacting protein, an HSP90-associated E3 ubiquitin ligase, mediated ILK ubiquitination to control PI3K- and HSP90-regulated ILK stabilization and signaling. In addition to cell growth, the identified pathway promoted cell migration and reduced the sensitivity of gastric cancer cells to the anticancer agents 5-fluorouracil and cisplatin. Additionally, exogenous administration of EGF as well as overexpression of EGFR triggered ILK- and IQGAP1-regulated ERK1/2/NF-κB activation, cell growth, and migration.ConclusionAn increase in ILK non-canonically promotes ERK1/2/NF-κB activation and leads to the growth of gastric cancer cells.Electronic supplementary materialThe online version of this article (doi:10.1186/s12964-014-0069-3) contains supplementary material, which is available to authorized users.

The use of keratin‐based wound products on refractory wounds

Keratin proteins have been shown to play a key role in wound healing. Controlled keratin gene (KRT) expression promotes cell growth, migration and differentiation, and as an example of the importance of keratin proteins, absence of KRT17 has been shown to delay wound closure. In addition, downregulation of KRT6 and KRT16 in non-healing chronic venous ulcers suggests that deregulation of keratin expression contributes to non-healing phenotype. A sample of 45 chronic wounds of mixed aetiologies presenting in 31 patients were treated with keratin-based novel topical wound healing products. Thirty-seven wounds or 82% of wounds were either healed or reduced in size of >50% during treatment, with 29 (64%) healing completely and an additional 8 wounds experiencing 50% wound size reduction or greater. Of the wounds that responded, 15 required antimicrobial treatment during their course of treatment, suggesting that keratin dressing treatment should be interrupted briefly and then restarted when wound infection occur.

An increase in integrin-linked kinase non-canonically confers NF-¿B-mediated growth advantages to gastric cancer cells by activating ERK1/2

BackgroundIncreased activity or expression of integrin-linked kinase (ILK), which regulates cell adhesion, migration, and proliferation, leads to oncogenesis. We identified the molecular basis for the regulation of ILK and its alternative role in conferring ERK1/2/NF-κB-mediated growth advantages to gastric cancer cells.ResultsInhibiting ILK with short hairpin RNA or T315, a putative ILK inhibitor, abolished NF-κB-mediated the growth in the human gastric cancer cells AGS, SNU-1, MKN45, and GES-1. ILK stimulated Ras activity to activate the c-Raf/MEK1/2/ERK1/2/ribosomal S6 kinase/inhibitor of κBα/NF-κB signaling by facilitating the formation of the IQ motif-containing GTPase-activating protein 1 (IQGAP1)-Ras complex. Forced enzymatic ILK expression promoted cell growth by facilitating ERK1/2/NF-κB signaling. PI3K activation or decreased PTEN expression prolonged ERK1/2 activation by protecting ILK from proteasome-mediated degradation. C-terminus of heat shock cognate 70 interacting protein, an HSP90-associated E3 ubiquitin ligase, mediated ILK ubiquitination to control PI3K- and HSP90-regulated ILK stabilization and signaling. In addition to cell growth, the identified pathway promoted cell migration and reduced the sensitivity of gastric cancer cells to the anticancer agents 5-fluorouracil and cisplatin. Additionally, exogenous administration of EGF as well as overexpression of EGFR triggered ILK- and IQGAP1-regulated ERK1/2/NF-κB activation, cell growth, and migration.ConclusionAn increase in ILK non-canonically promotes ERK1/2/NF-κB activation and leads to the growth of gastric cancer cells.

Reduced CTGF Expression Promotes Cell Growth, Migration, and Invasion in Nasopharyngeal Carcinoma

BackgroundThe role of CTGF varies in different types of cancer. The purpose of this study is to investigate the involvement of CTGF in tumor progression and prognosis of human nasopharyngeal carcinoma (NPC).Experimental designCTGF expression levels were examined in NPC tissues and cells, nasopharynx (NP) tissues, and NP69 cells. The effects and molecular mechanisms of CTGF expression on cell proliferation, migration, invasion, and cell cycle were also explored.ResultsNPC cells exhibited decreased mRNA expression of CTGF compared to immortalized human nasopharyngeal epithelial cell line NP69. Similarly, CTGF was observed to be downregulated in NPC compared to normal tissues at mRNA and protein levels. Furthermore, reduced CTGF was negatively associated with the progression of NPC. Knocking down CTGF expression enhanced the colony formation, cell migration, invasion, and G1/S cell cycle transition. Mechanistic analysis revealed that CTGF suppression activated FAK/PI3K/AKT and its downstream signals regulating the cell cycle, epithelial-mesenchymal transition (EMT) and MMPs. Finally, DNA methylation microarray revealed a lack of hypermethylation at the CTGF promoter, suggesting other mechanisms are associated with suppression of CTGF in NPC.ConclusionOur study demonstrates that reduced expression of CTGF promoted cell proliferation, migration, invasion and cell cycle progression through FAK/PI3K/AKT, EMT and MMP pathways in NPC.

Stanniocalcin1 (STC1) Inhibits Cell Proliferation and Invasion of Cervical Cancer Cells

STC1 is a glycoprotein hormone involved in calcium/phosphate (Pi) homeostasis. There is mounting evidence that STC1 is tightly associated with the development of cancer. But the function of STC1 in cancer is not fully understood. Here, we found that STC1 is down-regulated in Clinical tissues of cervical cancer compared to the adjacent normal cervical tissues (15 cases). Subsequently, the expression of STC1 was knocked down by RNA interference in cervical cancer CaSki cells and the low expression promoted cell growth, migration and invasion. We also found that STC1 overexpression inhibited cell proliferation and invasion of cervical cancer cells. Moreover, STC1 overexpression sensitized CaSki cells to drugs. Further, we showed that NF-κB p65 protein directly bound to STC1 promoter and activated the expression of STC1 in cervical cancer cells. Thus, these results provided evidence that STC1 inhibited cell proliferation and invasion through NF-κB p65 activation in cervical cancer.

Aplasia ras homolog member I is downregulated in gastric cancer and silencing its expression promotes cell growth in vitro

Aplasia ras homolog member I (ARHI) is a maternally imprinted tumor suppressor gene. ARHI protein is widely expressed in many types of human tissues; however, its expression is frequently reduced or absent in various tumors and plays a tumor suppressor role for in vitro study. In this study, we investigated the expression level of ARHI in gastric cancer in order to investigate the function of ARHI and signaling pathways that might be linked during gastric cancer development. ARHI mRNA and protein expression levels were analyzed in primary gastric cancer tissues, adjacent noncancerous gastric tissues and gastric cancer cell lines using semi-quantitative polymerase chain reaction, western blotting and immunohistochemistry, respectively. Our results showed that both mRNA and protein expression levels of the ARHI gene were significantly downregulated (P < 0.05) in gastric cancer tissues and cell lines compared to the corresponding normal control groups. The protein expression level of ARHI was not associated with age, gender, location of tumor, tumor size or metastasis in patients with gastric cancer. However, a significant correlation between the level of ARHI protein expression and the degree of tumor differentiation and Tumor-Node-Metastasis stage was observed (P < 0.05). Furthermore, results of the methyl thiazolyl tetrazolium and Transwell assays and flow cytometric analysis showed increased cell proliferation, migration and anti-apoptotic capacities in the well-differentiated gastric cancer MKN-28 cell line, which has stably silenced ARHI protein expression. Our data indicate that ARHI expression is downregulated in human gastric cancer and it may be a novel tumor suppressive target for gastric cancer therapy.

Expression and clinical significance of miR-23a and metastasis suppressor 1 in colon carcinoma

To investigate the expression of miR-23a and metastasis suppressor 1 (MTSS1) and their clinical significance in colon carcinoma. A total of 92 cases of colon carcinomas were collected with both the tumor and paired normal tissue samples for the study. The miR-23a targeting MTSS1 was evaluated by luciferase reporter vector. Cell invasion potential was evaluated by trans-well invasion assay. In-situ hybridization and immunohistochemistry were used to detect miR-23a and MTSS1 expression. MiR-23a downregulated the expression of MTSS protein and enhanced the invasiveness of colon carcinoma. The expression rates of miR-23a and MTSS1 were 87.0% (80/92) and 17.4% (16/92) in colon carcinoma cases, respectively (P < 0.01). The up-regulation of miR-23a expression was associated with an advanced clinical stage (P = 0.029) and depth of invasion (P = 0.000). The expression of miR-23a was higher in the tumors with lymph node metastasis than those without (P = 0.041). Down-regulation of MTSS1 expression was associated with an advanced clinical stage (P = 0.027) and depth of invasion (P = 0.017). The expression of MTSS1 was lower in the tumors with lymph node metastasis than those without (P = 0.009). The expression of miR-23a had significantly negative correlation with that of MTSS1 (r = -0.594, P = 0.013). MiR-23a expression promotes colon carcinoma cell growth, invasion and metastasis through inhibition of MTSS gene. Both the low expression of MTSS1 and high expression of miR-23a may serve as important biological markers for the malignant phenotypes of colon cancer, such as invasion and metastasis.

A Key Role for Tumor Suppressor BTG1 In the Regulation of Metabolic Stress Responses: Implications for Asparaginase Resistance In Pediatric Acute Lymphoblastic Leukemia.

AbstractAbstract 1028 Background:L-Asparaginase (ASNase) is a key component of multi-agent chemotherapy regimens used in the treatment of pediatric Acute Lymphoblastic Leukemia (ALL). This bacterially-derived enzyme lowers blood asparagine levels by catalyzing the hydrolysis of L-asparagine, leading to specific killing of leukemic blasts. However, relapses and associated therapy resistance occur in about 20% of the patients. Although the molecular mechanisms that contribute to ASNase resistance are not well understood, increased expression of asparagine synthethase (ASNS), the enzyme responsible for asparagine synthesis, has been linked to ASNase resistance both in ALL cell lines and in primary leukemias. We recently reported that micro-deletions affecting the B-cell translocation gene 1 (BTG1) occur in about 10% of pediatric pre-B ALL cases. Here we show that BTG1 loss contributes to ASNase resistance by up-regulation of ASNS. Results:Using RNA interference, we show that loss of BTG1 expression promotes cell growth and renders pre-B ALL cells completely refractory to ASNase induced cell death. Resistance to ASNase in the BTG1 knockdown cells is accompanied by increased expression of ASNS, while knockdown of this metabolic enzyme is sufficient to reverse therapy resistance, indicating that upregulation of ASNS is required for the observed resistance phenotype. We further show that BTG1 associates with and regulates the activity of the transcription factor ATF4, a key regulator of metabolic stress responses and a central component in the regulatory network that controls ASNS expression. Conclusion:Together, our experiments identify BTG1 as an important regulator of ASNS expression which acts by modulating ATF4 function. We expect that a detailed molecular understanding of how BTG1 loss contributes to ASNase resistance, will lead to the identification of pharmacological targets that can be used to improve treatment responses in therapy-resistant ALL. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Abstract 2355: Role of secreted frizzled-related protein 3 (sFRP3) in human renal cell carcinoma

Abstract Wnt/beta-catenin signaling is involved in renal cancer. Among Wnt antagonist families, sFRP3 is generally thought to be an inhibitor of Wnt signaling in several cancers. Here we reported the functional significance of sFRP3 in renal cell carcinoma. We performed immunohistochemistry on kidney tissue microarray and confirmed the expression level of sFRP3 in normal kidney and renal cancer cell lines (primary and metastatic). We transfected sFRP3 to the primary renal cancer cell lines and performed several functional analysis (MTS, colony formation, apoptosis, cell cycle, invasion, angiogenesis, and in vivo study). We also knocked down sFRP3 mRNA in metastatic cell lines using siRNA technique and performed several functional analysis. We found the level of sFRP3 protein was high in normal kidney, low in primary renal cancer tissues and high in metastatic renal cancer tissues. We performed dual sFRP3 mRNA expression experiments to determine the role of sFRP3 using primary and metastatic renal cancer cell lines. Functional analysis showed increased numbers of viable and invaded cells, tube formation and decreased numbers of apoptotic cells in sFRP3 transfected A498 cells. Promotion of tumor growth was also observed in nude mice injected with sFRP3 transfected A498 cells. In contrast, the number of viable cells and invasive cells was decreased in sFRP3 mRNA knocked down metastatic cells (ACHN and Hs891.T). To investigate the mechanism of sFRP3 function, we performed microarray analysis to see which genes were up or down regulated by sFRP3 expression. Among these genes, MMP-3 and ANGPT1 were significantly up-regulated in sFRP3 transfected cells. This is the first report to show that sFRP3 expression promotes cell growth, invasion, and inhibition of apoptosis in renal cancer cells. Furthermore, our results suggest that sFRP3 may play a role in invasion and angiogenesis by enhancing MMP-3 and ANGPT1 expression. The changes in sFRP3 expression levels in normal, primary cancer, and metastatic renal cancer tissues suggest that sFRP3 may play dual roles as a tumor suppressor gene and an oncogene during renal cancer progression. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2355.

362 ROLE OF SECRETED FRIZZLED-RELATED PROTEIN 3 (SFRP3) IN HUMAN RENAL CELL CARCINOMA

You have accessJournal of UrologyKidney Cancer: Basic Research III1 Apr 2010362 ROLE OF SECRETED FRIZZLED-RELATED PROTEIN 3 (SFRP3) IN HUMAN RENAL CELL CARCINOMA Hiroshi Hirata, Yuji Hinoda, Koji Ueno, Shahana Majid, Sharanjot Saini, Peter Carroll, and Rajvir Dahiya Hiroshi HirataHiroshi Hirata San Francisco, CA More articles by this author , Yuji HinodaYuji Hinoda Ube, Japan More articles by this author , Koji UenoKoji Ueno San Francisco, CA More articles by this author , Shahana MajidShahana Majid San Francisco, CA More articles by this author , Sharanjot SainiSharanjot Saini San Francisco, CA More articles by this author , Peter CarrollPeter Carroll San Francisco, CA More articles by this author , and Rajvir DahiyaRajvir Dahiya San Francisco, CA More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.429AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Wnt/beta-catenin signaling is involved in renal cancer. Canonical Wnt ligands bind to frizzled (FZD) family receptors and the LRP5/LRP6 co-receptor, which stabilize beta-catenin. Among Wnt antagonist families, sFRP3 is generally thought to be an inhibitor of Wnt signaling in several cancers. However, sFRP2, which is also a member of the sFRP family, has been previously reported to be involved in oncogenic function in human glioma cells. Here we reported the functional significance of sFRP3 in renal cell carcinoma. METHODS We performed immunohistochemistry on kidney tissue microarray and confirmed the expression level of sFRP3 in normal kidney and renal cancer cell lines (primary and metastatic). We transfected sFRP3 to the primary renal cancer cell lines and performed several functional analysis (MTS, colony formation, apoptosis, cell cycle, invasion, angiogenesis, and in vivo study). We also knocked down sFRP3 mRNA in metastatic cell lines using siRNA technique and performed several functional analysis. Besides we profiled cell cycle, apoptosis, and invasion related genes with microarray. RESULTS We found the level of sFRP3 protein was high in normal kidney, low in primary renal cancer tissues and high in metastatic renal cancer tissues. We performed dual sFRP3 mRNA expression experiments to determine the role of sFRP3 using primary and metastatic renal cancer cell lines. Functional analysis showed increased numbers of viable and invaded cells, tube formation and decreased numbers of apoptotic cells in sFRP3 transfected A498 cells. Promotion of tumor growth was also observed in nude mice injected with sFRP3 transfected A498 cells. In contrast, the number of viable cells and invasive cells was decreased in sFRP3 mRNA knocked down metastatic cells (ACHN and Hs891.T). To investigate the mechanism of sFRP3 function, we performed microarray analysis to see which genes were up or down regulated by sFRP3 expression. Among these genes, MMP-3 and ANGPT1 were significantly up-regulated in sFRP3 transfected cells. CONCLUSIONS This is the first report to show that sFRP3 expression promotes cell growth, invasion, and inhibition of apoptosis in renal cancer cells. Furthermore, our results suggest that sFRP3 may play a role in invasion and angiogenesis by enhancing MMP-3 and ANGPT1 expression. The changes in sFRP3 expression levels in normal, primary cancer, and metastatic renal cancer tissues suggest that sFRP3 may play dual roles as a tumor suppressor gene and an oncogene during renal cancer progression. © 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e143-e144 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Hiroshi Hirata San Francisco, CA More articles by this author Yuji Hinoda Ube, Japan More articles by this author Koji Ueno San Francisco, CA More articles by this author Shahana Majid San Francisco, CA More articles by this author Sharanjot Saini San Francisco, CA More articles by this author Peter Carroll San Francisco, CA More articles by this author Rajvir Dahiya San Francisco, CA More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Role of Secreted Frizzled-Related Protein 3 in Human Renal Cell Carcinoma

The secreted frizzled-related protein (sFRP) family plays an important role in the inhibition of the Wnt signaling pathway in various cancers. The functional significance of Wnt antagonist sFRP3 has not been investigated in renal cancer. We performed tissue microarray and found that the level of sFRP3 protein was high in normal kidney, low in primary renal cancer tissues, and high in metastatic renal cancer tissues. Therefore, we hypothesized that sFRP3 may play an important role in metastatic renal cancer. To test this hypothesis, we performed a series of experiments to determine the role of sFRP3 using primary and metastatic renal cancer cell lines. Functional analysis showed increased numbers of viable and invaded cells and tube formation and decreased numbers of apoptotic cells in the sFRP3-transfected renal cancer cell line A498. Promotion of tumor growth was also observed in nude mice injected with sFRP3-transfected A498 cells. In contrast, the number of viable cells and invasive cells was decreased in sFRP3 mRNA knockdown metastatic cells (ACHN and Hs891.T). To investigate the mechanism of sFRP3 function, we performed microarray analysis to see which genes were upregulated or downregulated by sFRP3 expression. Among these genes, MMP-3 and ANGPT1 were significantly upregulated in sFRP3-transfected cells. In conclusion, this is the first report to show that sFRP3 expression promotes cell growth, invasion, and inhibition of apoptosis in renal cancer cells.