Renal Cell Carcinoma Cell Invasion Research Articles

Hypermethylation of BRM promoter plays oncogenic roles in development of clear cell renal cell carcinoma.

Although the inactivation of BRM plays oncogenic roles in tumorigenesis, regulation mechanism is rarely studied in clear cell renal cell carcinoma (RCC). Thus, we aimed to investigate the mechanism of BRM inactivation and explore the tumor suppressing roles of BRM in the development of clear cell RCC. We verified that hypermethylation of the BRM promoter was correlated with decreased expression of BRM by multi-omics analysis based on the TCGA database. This result was further confirmed in our own tumor tissues. Moreover, BRM inhibited the ability of proliferation and invasion of RCC cells in vitro. Consistent with this, BRM overexpressing virtually inhibited the xenograft tumor growth of ACHN cells in vivo. Finally we found that BRM promoted cell apoptosis and cellular cycle arrest in G2/M. In conclusion, our study confirms that the hypermethylation of BRM promoters plays oncogenic roles by the transcription inhibition of BRM in RCC, and the tumor suppressor gene BRM inhibits RCC cell vitality in vitro and in vivo.

FBXO22 Suppresses Metastasis in Human Renal Cell Carcinoma via Inhibiting MMP-9-Mediated Migration and Invasion and VEGF-Mediated Angiogenesis.

F-box only protein 22 (FBXO22), a substrate receptor of the SKP1-Cullin 1-F-box protein (SCF) E3 ubiquitin ligase that targets key regulators of cellular activities for ubiquitylation and degradation, plays important roles in the progression of human cancer. However, little is known about the role of FBXO22 in renal cell carcinoma (RCC). This study aims to explore the biological function of FBXO22 in RCC progression and its specific regulation mechanism. We performed immunohistochemistry analysis and found that the expression level of FBXO22 was significantly lower in RCC tissues than in normal renal tissues. Reduced FBXO22 expression in RCC tissues is related to tumor size and TNM stage and to worse overall and disease-free survival. Through an in vitro assay, we demonstrated that FBXO22 has no effect on renal cancer cells proliferation, whereas FBXO22 remarkably restricted RCC cell migration and invasion, thereby reversing EMT transition and elevating the activity of tissue inhibitor of matrix metalloproteinase-1, which subsequently inhibited metalloproteinase-9 (MMP-9) expression and activity in vitro. We also found that FBXO22 suppresses tube formation by disrupting the secretion of vascular endothelial growth factor. Meanwhile, in vivo studies verified that FBXO22 suppresses RCC metastasis. These findings suggested that FBXO22 is a novel prognostic indicator and plays an important role in RCC metastasis.

MiR-31-5p acts as a tumor suppressor in renal cell carcinoma by targeting cyclin-dependent kinase 1 (CDK1)

Background: Renal cell carcinoma (RCC) accounts for more than 90% of cancers in the kidney. RCC is often asymptomatic, as a result people with RCC generally have advanced disease by the time it is discovered and has a poor prognosis compared to other cancers. Therefore, it is necessary to explore its pathogenesis and identify some reliable prognostic biomarker of RCC. miRNAs are emerging as important players in the development and progression of RCC. miR-31-5p has been reported to act as a tumor suppressor in hepatocellular carcinoma (HCC). The aim of this study is to determine the detailed molecular mechanism of miR-31-5p in the progression of RCC and to investigate its potential clinical value.Methods: In this study, RT-qPCR, EdU assay, CCK-8 assay, wound scratch assay, transwell assay, flow cytometry assay and cell cycle assay were performed to detect miR-31-5p expression and its functions in RCC. Moreover, 42 formalin-fixed paraffin-embedded (FFPE) RCC samples were used to analyze the relationship between miR-31-5p expression and patients’ overall survival. Finally, luciferase reporter assay, RT-qPCR assay and western blot were used to explore the association between miR-31-5p and its potential targets.Results: miR-31-5p was significantly down-regulated in RCC tissues and RCC cell lines compared with paired adjacent normal tissues and normal cell lines. miR-31-5p downregulation was associated with poor prognosis in RCC patients. Overexpression of miR-31-5p inhibited RCC cell proliferation, migration and invasion and cell cycle. Conversely, down-regulation of miR-31-5p promoted cell proliferation, migration and invasion. Furthermore, cyclin-dependent kinasec1 (CDK1), a key player in cell cycle regulation, was identified as a functional target of miR-31-5p.Conclusions: Our results suggest that miR-31-5p serves as a tumor suppressor in RCC and is expected to be a molecular biomarker for poor prognosis of RCC.

MicroRNA-372 functions as a tumor suppressor in cell invasion, migration and epithelial-mesenchymal transition by targeting ATAD2 in renal cell carcinoma.

In recent years, renal cell carcinoma (RCC) has exhibited an increasing incidence and mortality rate worldwide. Accumulating evidence has identified that microRNAs (miRNAs) function as negative or positive regulators of many malignant tumors; however, the roles of miR-372 in RCC remain unclear. The focus of the present study was the functions of miR-372 in RCC metastasis and EMT. Data revealed that miR-372 expression levels were significantly downregulated in RCC tissue samples and cells. Moreover, the decreased expression levels were strongly associated with the poor survival rates and adverse clinical characteristics of RCC patients. Accordingly, miR-372 overexpression markedly inhibited RCC cell invasion, migration and EMT. In terms of the potential mechanisms, ATAD2, the expression of which was inversely correlated with miR-372 expression in RCC, was identified as a direct functional target of miR-372. Notably, ATAD2 silence exerted suppressive functions in RCC cells, being similar to the effects of miR-372 overexpression. In conclusion, findings of this study indicate that miR-372 repressed RCC EMT and metastasis via targeting ATAD2, suggesting that the miR-372/ATAD2 axis may be therapeutic biomarkers for RCC.

Long non-coding RNA HOTTIP affects renal cell carcinoma progression by regulating autophagy via the PI3K/Akt/Atg13 signaling pathway.

Renal cell carcinoma (RCC) is the most common malignancy of the urinary system, and it is a serious threat to human health. HOXA transcript at the distal tip (HOTTIP), located at the 5' end of the HOXA locus, is a long non-coding RNA that has been newly discovered in recent years. It has been reported to promote the development of several types of tumors. Moreover, accumulating evidence has indicated that autophagy plays an important role in tumor cell survival or death. However, whether HOTTIP affects RCC development by regulating autophagy remains unknown. In this study, we first measured HOTTIP expression in 42 paired RCC and adjacent non-tumor tissues, as well as in 4 RCC cell lines and 1 normal renal tubular epithelial cell line. Then, we selected 2 RCC cell lines to silence HOTTIP expression and 1 RCC cell line to overexpress HOTTIP, and we measured their proliferation, migration and invasion, as well as autophagy, after pretreatment with an autophagy inhibitor or inducer. In addition, we assessed the growth, metastasis and autophagy of tumors in nude mice and explored the mechanism involved. The results showed that HOTTIP expression was significantly upregulated in the RCC tissues and cell lines, and it was closely associated with TNM stage, histological grade, lymph node metastasis and patient prognosis. The in vitro and in vivo assays indicated that HOTTIP silencing inhibited RCC cell proliferation, migration and invasion and induced autophagy, and 3-MA (an autophagy inhibitor) reversed these effects. In contrast, HOTTIP overexpression and rapamycin (an autophagy inducer) yielded the opposite results. Further research revealed that HOTTIP modification could affect RCC cell autophagy via the PI3K/Akt/Atg13 signaling pathway. Our study will help in finding a potential marker for RCC diagnosis and supply a target molecule for RCC treatment.

Low expression of PDK1 inhibits renal cell carcinoma cell proliferation, migration, invasion and epithelial mesenchymal transition through inhibition of the PI3K-PDK1-Akt pathway

As the most commonly occurring form of primary renal tumor, renal cell carcinoma (RCC) is a malignancy accompanied by a high mortality rate. 3-phosphoinositide-dependent protein kinase 1 (PDK1) has been established as a protein target and generated considerable interest in both the pharmaceutical and academia industry. The aim of the current study was to investigate the effect of si-PDK1 on the RCC cell apoptosis, proliferation, migration, invasion and epithelial mesenchymal transition (EMT) in connection with the PI3K-PDK1-Akt pathway. Microarray analysis from the GEO database was adopted to identify differentially expressed genes (DEGs) related to RCC, after which the positive expression of the PDK1 protein in tissue was determined accordingly. The optimal silencing si-RNA was subsequently selected and RCC cell lines 786-O and A498 were selected and transfected with either a si-PDK1 or activator of the PI3K-PDK1-Akt pathway for grouping purposes. The mRNA and protein expressions of PDK1, the PI3K-PDK1-Akt pathway-, EMT- and apoptosis-related genes were then evaluated. The effect of si-PDK1 on cell proliferation, apoptosis, invasion and migration was then analyzed. Through microarray analysis of GSE6344, GSE53757, GSE14762 and GSE781, PDK1 was examined. PDK1 was determined to be highly expressed in RCC tissues. Si-PDK1 exhibited marked reductions in relation to the mRNA and protein expression of PDK1, PI3K, AKT as well as Vimentin while elevated mRNA and protein expressions of E-cadherin were detected, which ultimately suggested that cell migration, proliferation and invasion had been inhibited coupled with enhanced levels of cell apoptosis. While a notable observation was made highlighting that the PI3K-PDK1-Akt pathway antagonized the effect of PDK1 silencing. Taken together, the key observations of this study provide evidence suggesting that high expressions of PDK1 are found in RCC, while highlighting that silencing PDK1 could inhibit RCC cell proliferation, migration, invasion and EMT by repressing the PI3K-PDK1-Akt pathway.

Sunitinib-suppressed miR-452-5p facilitates renal cancer cell invasion and metastasis through modulating SMAD4/SMAD7 signals

PurposeAlthough microRNAs (miRNAs) were revealed as crucial modulators in tumor metastasis and target therapy, our understanding of their roles in metastatic renal cell carcinoma (mRCC) and Sunitinib treatment was limited. Here we sought to identify human miRNAs that acted as key regulators in renal cancer metastasis and Sunitinib treatment.Experimental designWe focused on 2 published microarray data to select out our anchored miRNA and then explored the roles of miR-452-5p both in vitro and in vivo, which was downregulated after Sunitinib treatment while upregulated in metastasis renal cell carcinoma (RCC) tissues.ResultsHere, we discovered that treating with Sunitinib, the targeted receptor tyrosine kinase inhibitor (TKI), inhibited renal cancer cell migration and invasion via attenuating the expression of miR-452-5p. The novel identified miR-452-5p was upregulated and associated with poor prognosis in RCC. Preclinical studies using multiple RCC cells and xenografts model illustrated that miR-452-5p could promote RCC cell migration and invasion in vitro and in vivo. Mechanistically, P65 could directly bind to the miR-452-5p promoter and thus transcriptionally induce miR-452-5p expression, which led to post-transcriptionally abrogate SMAD4 expression, thus inhibition of its downstream gene SMAD7.ConclusionOur study presented a road map for targeting this newly identified miR-452-5p and its SMAD4/SMAD7 signals pathway, which imparted a new potential therapeutic strategy for mRCC treatment.

Targeting newly identified ERβ/TGF-β1/SMAD3 signals with the FDA-approved anti-estrogen Faslodex or an ERβ selective antagonist in renal cell carcinoma.

Renal cell carcinoma (RCC) has the third highest mortality rate among urological tumors, and 20–30% of RCC patients present with metastatic RCC at the time of diagnosis. Although recent studies have indicated that estrogen receptor β (ERβ) could play promoting roles in RCC progression, the detailed mechanisms remain to be clarified. In the present study, we found that expression of ERβ, but not ERα, increases with tumor stage and grade, and also observed that modification of ERβ signals using estrogens/anti‐estrogens, shRNA knockdown of ERβ and overexpression of ERβ using ectopic cDNA affects RCC cell proliferation, migration and invasion. Mechanism analysis revealed that ERβ can promote RCC cell invasion via an increase in transforming growth factor β1 (TGF‐β1)/SMAD3 signals, and interrupting TGF‐β1/SMAD3 signals with a TGFβR1 inhibitor can reverse/block ERβ‐increased RCC cell migration. Importantly, preclinical analyses using in vivo mouse models of RCC revealed that targeting of this newly identified ERβ/TGF‐β1/SMAD3 pathway with either the FDA‐approved anti‐estrogen ICI182,780 (Faslodex) or a selective ERβ antagonist 4‐[2‐phenyl‐5,7 bis(trifluoromethyl)pyrazolo[1,5‐a]pyrimidin‐3‐yl]phenol can significantly reduce RCC tumor growth and invasion, which may be suitable as the basis for novel therapies to more effectively suppress metastatic RCC.

Long noncoding RNA TUG1 promotes renal cell carcinoma cell proliferation, migration and invasion by downregulating microRNA‑196a.

Long noncoding RNA taurine upregulated gene1 (lncRNA TUG1) and microRNA‑196a (miR‑196a) have been reported to serve important roles in the development of renal cell carcinoma (RCC). However, their potential mechanisms have not been completely elucidated. The aim of the present study was to clarify the biological functions of lncRNA‑TUG1 and miR‑196a, in addition to investigating the interaction between lncRNA‑TUG1 and microRNA‑196a, providing a novel insight into RCC tumorigenesis. The present study comprised two parts. In the first part, lncRNA‑TUG1 was confirmed as an oncogene, via reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) analysis, MTT assay, flow cytometry analysis, and migration and invasion assays. In the second part, the association between lncRNA‑TUG1 and miR‑196a, and the molecular mechanism, was illustrated via RT‑qPCR analysis, MTT assay, dual luciferase reporter assay and western blotting. The results of the present study demonstrated that lncRNA‑TUG1 was able to promote RCC cell proliferation, migration and invasion invitro by suppressing miR‑196a. Additionally, lncRNA‑TUG1 achieved its biological functions by regulating the expression levels of RAC‑α serine/threonine‑protein kinase, mitogen‑activated protein kinase and extracellular signal‑regulated kinase via inhibition of miR‑196a. In conclusion, the present findings proposed a novel potential therapeutic target, the lncRNA‑TUG1‑miR‑196a axis, which may be applicable to the treatment of RCC.

LINC00961 restrains cancer progression via modulating epithelial-mesenchymal transition in renal cell carcinoma.

Recently, long noncoding RNA have been identified as new gene regulators and prognostic biomarkers in various cancers, including renal cell carcinoma (RCC). The expression and biological roles of LINC00961 have been reported in many human cancers. However, up to date, no study of LINC00961 has been shown in RCC. Currently, we aimed to investigate the function of LINC00961 in RCC progression. Interestingly, we observed that LINC00961 could act as a novel biomarker in predicting the diagnosis of RCC. Then, we found that LINC00961 was greatly downregulated in RCC cell lines (Caki-1, Caki-2, 786-O, A498, and ACHN cells) compared with normal renal cell lines (HK-2 cells). Then, 786-O cells and ACHN cells were infected with LV-LINC00961. As displayed in our current study, LINC00961 overexpression could obviously suppress the proliferation and survival of RCC cells in vitro. In addition, RCC cell apoptosis was greatly induced and cell cycle progression was blocked in G1 phase by upregulation of LINC00961 in 786-O cells and ACHN cells. Subsequently, we found that LV-LINC00961 was able to restrain RCC cell migration and cell invasion capacity. Meanwhile, the messenger RNA and protein expression levels of epithelial-mesenchymal transition (EMT)-associated markers Slug and N-cadherin in RCC cell lines were dramatically inhibited by overexpressing LINC00961. Finally, the in vivo experiment was carried out and we observed that LINC00961 could inhibit RCC development through modulating EMT process. Taken these together, it was indicated in our study that LINC00961 was involved in RCC progression through targeting EMT pathway.

Degalactotigonin Exerts Effective Inhibition on the Growth, Metastasis and Sunitinib-Resistance of Renal Cell Carcinoma Through Inactivating YAP Signaling

Background: The pervasive progression and drug-resistance of renal cell carcinoma (RCC) after treatments demands for more effective drugs with little side effects. Recently, extracts from natural resources have been reported to effectively suppress the progression of certain tumors. In this study, we examined the effects of degalactotigonin extracted from Solanum nigrum L. on the progression and sunitinib-resistance of RCC, and the underlying mechanisms. Methods: The in vitro effects of degalactotigonin on the proliferation, apoptosis, invasion, migration and sunitinib-resistance were assessed by CCK-8, flow cytometry, Western blot, Matrigel invasion and transwell migration assays. The in vivo effects were evaluated in murine models of subcutaneous and in situ tumor and lung metastasis. The related molecular characteristics were delineated by RNA-sequencing. Findings: Degalactotigonin induced apoptosis and suppressed proliferation, invasion, migration, and sunitinib-resistance of RCC cells in vitro in a dose-dependent manner. Furthermore, degalactotigonin effectively inhibited the tumorigenicity and lung metastasis of RCC cells in vivo. Mechanistically, RNA-sequencing revealed that inactivation of YAP signaling occurred in degalactotigonin-treated RCC cells with reduced expression of YAP and its target genes. We also observed that degalactotigonin activated p-LATS1/2 to phosphorylate YAP, which induced more YAP retention in the cytoplasm but less YAP entering the nucleus of RCC cells. Moreover, re-expressed YAP in degalactotigonin-treated RCC cells mediated the anti-tumor activities of degalactotigonin on RCC. Furthermore, degalactotigonin ameliorated sunitinib-resistance in an orthotopic RCC model. Interpretation: Degalactotigonin is an effective therapeutic agent in inhibiting the growth, progression and sunitinib-resistance of RCC. Funding Statement: National Natural Science Foundation of China (No. 81773154, 81772747 and 81301861), Shanghai Natural Science Foundation of China (No. 13ZR1450700), the Shanghai Medical Guidance (Chinese and Western Medicine) Science and Technology Support Project (No. 17411960200). Declaration of Interests: The authors declare no potential conflicts of interest. Ethics Approval Statement: All experimental animal procedures were approved by the Animal Care and Use Committee of the Second Military Medical University (Shanghai, China).

886P - Adiponectin-AdipoR1 axis in renal cell carcinoma plays a pivotal role in tumor progression and drug resistance

Background: It is well established that renal cell carcinoma (RCC) is an obesity-associated cancer. Adiponectin, a major adipocyte-secreted adipokine, plays anti-tumor properties in many malignancies, but exerted paradoxical actions on RCC. Herein, we investigated the effects of adiponectin on RCC progression and resistance to sunitinib, and to exploit this molecular mechanism. Methods: Tissues were collected from 126 patients with metastatic renal cell carcinoma (mRCC) treated with tyrosine kinase inhibitor (TKI) therapy. Tumor Adiponectine receptor 1 (AdipoR1) and Adiponectine receptor 2 (AdipoR2) were detected by immunohistochemistry. Assays with RCC cell lines were used to examine the signal transduction pathways of adiponectin in RCC. Results: AdipoR2 was generally lower expressed than AdipoR1 in mRCC tumor (15.6% vs 89.1%, p < 0.001). AdipoR1 expression, but not AdipoR2, was a significant independent predictor of favorable responding to TKI and good survival outcomes. In cultured RCC cells adiponectin inhibited migration and invasion of RCC cells and sensitized cells to killing by sunitinib. Mechanistic investigations of ligand–receptor interactions revealed that AdipoR1 could hinder migration and invasion of RCC cells by blocking GSK3β and β-Catenin pathway and increase cells sensitivity to sunitinib through inhibiting AKT and NF-κB pathway. However, AdipoR2 was not associated with the tumor-limiting properties of adiponectin. Conclusions: These results show that AdipoR1 is a potential prognostic marker for favorable outcomes of mRCC patients. Adiponectin-AdipoR1 axis could be a plausible target to impede tumor progression and sensitize tumors to TKI therapy. Legal entity responsible for the study: Guangxi Sun. Funding: National Natural Science Foundation of China (NSFC 81672547, 81402110), the Science and Technology Support Program of Sichuan Province (2015SZ0230-3) and 1.3.5 project for disciplines of excellence, West China Hospital, Sichuan University. Disclosure: All authors have declared no conflicts of interest.

Salinomycin suppresses cancer cell stemness and attenuates TGF-β-induced epithelial-mesenchymal transition of renal cell carcinoma cells

Metastatic Renal cell carcinoma (RCC) remains a difficult oncologic challenge. Salinomycin is a monocarboxylic polyether antibiotic, which has been proved to possess anti-tumor activities in multiple types of cancer cells. However, its effects on RCC cells remains unclear. In our study, salinomycin could inhibit the proliferation and viability of RCC cell lines 786-O and ACHN. The TUNEL assay revealed that treatment with salinomycin induced DNA breaking in RCC cells. Consistently, Western blotting showed up-regulation of pro-apoptotic biomarkers (cleaved caspase3/9 and cleaved PARP1) and down-regulation of anti-apoptotic biomarker (survivin) in RCC cells after salinomycin treatment, suggesting that salinomycin could induce RCC cell apoptosis. salinomycin treatment also suppressed the sphere formation ability of RCC cells and decreased the expressions of CD105, ALDH1 and CD44, biomarkers for reflecting the stemness of RCC cells. salinomycin treatment effectively down-regulated SMO and Gli1, two key proteins in Hedghog signaling pathway, in a dose-dependent manner. Moreover, salinomycin could suppress the invasion and migration of RCC cells in the presence of TGF-β1, as observed in wound-healing and Transwell assays. salinomycin treatment attenuated TGF-β1-induced epithelial-mesenchymal transition (EMT), as evidenced by its ability to increase E-cadherin expression and decrease N-cadherin, Snail and MMP-2 expressions in RCC cells. Finally, salinomycin inhibited the tumorigenecity of RCC cells in vivo. Our study provides the evidence that salinomycin possess multiple anti-tumor activities against RCC, as it, in particular, suppressed the cancer stem cell properties and attenuated TGF-β-induced EMT. Therefore, it may serve as a potentially therapeutic candidate for metastatic RCC and improve the prognosis of RCC patients.

LINC01510 suppresses cell proliferation and invasion by inhibiting Wnt/β-catenin signaling in renal cell carcinoma

The role of long non-coding RNA in Renal cell carcinoma (RCC) tumorigenesis and progression remains largely unknown. Here, we found that LINC01510 functions as a tumor suppressor in RCC tumorigenesis. We screened TCGA database and then found that LINC01510 is significantly down-regulated in malignant RCC tissues, and the lower expression of LINC01510 predicts poor prognosis. Moreover, the down-regulated LINC01510 was further confirmed in our fresh tissues and cell lines. Biological functions assays shown that Ectopic expression of LINC01510 not only inhibits RCC cell proliferation both in vitro and in vivo, but also impairs cell invasion ability. Moreover, we found overexpression of LINC01510 inhibits the expression of CCND1 and CCNE1, as well as MMPs (MMP2, MMP7 and MMP9), and thus affecting RCC cell cycle and invasion. Meanwhile, Western blot assays revealed that the expression of β-catenin is regulated by LINC01510; overexpression of β-catenin could partly rescue the cell viability and invasion ability caused by ectopic expression of LINC01510. Taken together, we found that LINC01510 regulates cell proliferation and invasion by modulating Wnt/β-catenin signaling in RCC.

Scutellarin inhibits human renal cancer cell proliferation and migration via upregulation of PTEN

BackgroundScutellarin is a naturally flavone glycoside that has been shown to exhibit anti-proliferative and anti-apoptotic activities among various human malignancies. However, the anti-cancer effect of Scutellarin in Renal cell carcinoma (RCC) and the underlying mechanism remains unclear. Methods and materialsRCC cell lines ACHN and 786-O were treated with different concentrations (0–210 μM) of Scutellarin in vitro. Cell viability and proliferation were investigated by MTT and colony formation assays. Cell invasion and migration were detected by Transwell assays. Cell apoptosis and cell cycle distribution was measured by flow cytometry. Western blot was used to investigate the expression levels of crucial proteins. Xenograft tumor model was established to evaluate tumor growth in vivo. ResultsScutellarin significantly inhibited RCC cell proliferation in a dose- and time- dependent manner. Treatment of RCC cells with Scutellarin (30, 60, and 90 μM) markedly induced apoptosis and cell cycle arrested at G0/G1 phase in a concentration-dependent characteristic. Cell invasion and migration capacities of RCC cells were also dose-dependently suppressed by Scutellarin treatment. Western blot assays revealed that the crucial proteins including cyclin D1, CDK2, Bcl2, MMP-2, and MMP-9 were significantly reduced while Bax, cleaved caspase 3 and p21 were increased by Scutellarin in RCC cells. In vivo assay indicated that Scutellarin possessed anti-cancer effect on xenograft without triggering toxic effect. Mechanically, Scutellarin dramatically increased the protein level of phosphatase and tensin homologue (PTEN) and inhibited the activity of P13K/AKT/mTOR signaling. Ectopic expression of PTEN enhanced the inhibitory effect of Scutellarin on RCC proliferation while knockdown of PTEN abrogated it through regulating its downstream P13K/AKT/mTOR signaling pathway. ConclusionScutellarin inhibited RCC cell proliferation and invasion partially by enhancing the expression of PTEN through inhibition of P13K/AKT/mTOR pathway, suggesting that Scutellarin might serve as a potential therapeutic agent in RCC treatment.

Really interesting new gene finger protein 121 is a tumor suppressor of renal cell carcinoma

Really interesting new gene finger protein (RING) finger protein 121 (RNF-121) is an E3 ubiquitin ligase involved in the regulation of several signaling pathways. Among those signaling pathways, nuclear factor-κB (NF-κB) signaling pathway is known to play a critical role in tumorigenesis. However, the relevance between RNF121 and cancer development remains poorly understood. In this study, we found that RNF121 was less expressed in tumor tissues than adjacent normal tissues of renal cell carcinoma (RCC) patients. Overexpression of RNF121 inhibited the growth of human RCC cells (768-O cell line) in vivo. Moreover, RNF121 impeded the proliferation, migration and invasion of human RCC cells in vitro. In addition, we found that RNF121 activated NF-κB signaling pathway via promoting IκBα degradation in human RCC cells. Our findings reveal a previously unrecognized role of RNF121 in RCC development, and provide new insights into RCC prognosis and therapy.

Oncogene miR-154-5p regulates cellular function and acts as a molecular marker with poor prognosis in renal cell carcinoma

AimsIn adult population, the renal cell carcinoma (RCC) is one of the most common urological malignancies. It is meaningful to research for the molecular markers which are involved in the occurrence and development of RCC. Therefore, we concentrate on illuminating the role of microRNA-154-5p in progression of RCC and explore its prognostic values. Main methodsThe real-time quantitative polymerase chain reaction (RT-qPCR) was applied to determine expression level of miR-154-5p in tissues. Afterwards, the transfected cell lines ACHN and 786-O were used for the CCK-8 assay, MTT assay, wound healing assay, transwell assay and flow cytometric assay to explore the role of miR-154-5p in regulating cellular function. In addition, formalin-fixed paraffin-embedded (FFPE) renal cancer samples were used for detecting the relationship between expression level of miR-154-5p and clinical information. Furthermore, univariate and multivariate Cox proportional-hazards regression analyses, and the Kaplan-Meier survival curves were performed to evaluate the prognostic value of miR-154-5p in RCC. Key findingsThe RT-qPCR indicated that miR-154-5p is up-regulated in RCC pathologic specimens and cell lines. Results of study also demonstrated that upregulation of miR-154-5p reduced cell apoptosis and promoted cell proliferation, viability, migration as well as invasion in RCC cells. The prognosis analyses indicated that the expression level of miR-154-5p is associated with the prognosis of renal cancer, and the overall survival of patients with low expression is longer. SignificanceThe present study revealed that the oncogene miR-154-5p regulates cellular function and acts as a molecular marker with poor prognosis in renal cell carcinoma.

Long noncoding RNA HOTAIR promotes renal cell carcinoma malignancy through alpha-2, 8-sialyltransferase 4 by sponging microRNA-124.

Accumulating evidence demonstrated that the long noncoding RNA (lncRNA) HOTAIR (Hox transcript antisense intergenic RNA) plays key role in renal cell carcinoma (RCC) malignancy, while microRNA-124 (miR-124) is a tumour suppressor in RCC. The aim of this work was to assess the biological function of HOTAIR and to explore underlying mechanism involved in HOTAIR/miR-124/alpha-2, 8-sialyltransferase 4 (ST8SIA4) axis-regulated progression in RCC. Real-time PCR analyses and western blots were performed to the levels of HOTAIR, miR-124 and ST8SIA4 expression in human RCC tissues and RCC cell lines (ACHN and 786-O). Bioinformatics analysis and dual-luciferase reporter assay were used to illustrate relationship between HOTAIR and miR-124 in RCC. Colony formation assays, EdU assays, Ki67 assays and apoptosis assays were taken to evaluate cell proliferation. Tumour xenograft was created to explore the functions of HOTAIR and ST8SIA4 in tumorigenesis in vivo. Migration assays, invasion assays and cell adhesion assays and were also taken to analyse the carcinoma progression. In this study, HOTAIR level was confirmed to be significantly upregulated in RCC samples and RCC cell lines compared with those in the paired adjacent tissues and normal renal cell line. Overexpression of HOTAIR promoted the capability of proliferation, migration and invasion in RCC cell lines. HOTAIR directly bound to miR-124, while miR-124 mediated the expression of ST8SIA4 in RCC cell lines. ST8SIA4 was upregulated in RCC tissues and RCC cell lines. Ectopic expression of ST8SIA4 modulated the proliferation, migration and invasion of RCC cells. Further results indicated that HOTAIR promoted the proliferation and metastasis as a competing endogenous RNA to regulate ST8SIA4 expression by sponging miR-124 in RCC. Our results demonstrated that HOTAIR mediated RCC progression in part through miR-124/ST8SIA4 axis, which functioned as a new prognostic biomarker in RCC.

RNAa and Vector-Mediated Overexpression of DIRAS1 Suppresses Tumor Growth and Migration in Renal Cell Carcinoma

The downregulation of DIRAS1 has been suggested to potentially contribute to tumor development and progression in several human cancers. However, the role of DIRAS1 in renal cell carcinoma (RCC) remains elusive. In this study, we examined the DIRAS1 expression level in RCC cell lines and tissues. Both RNA activation (RNAa) and vector transfection methods were used to upregulate the expression of DIRAS1 in RCC cells. Expression analysis revealed that DIRAS1 was significantly downregulated in RCC cell lines and tissues compared with nontumorigenic renal cells and adjacent nontumor tissues individually. Promoter methylation analysis indicated that the reduced DIRAS1 expression might be partly mediated by epigenetic modulation. The RNAa-mediated overexpression of DIRAS1 inhibited cell proliferation and tumorigenicity in vitro and in vivo. The re-activation of DIRAS1 also promoted apoptosis and suppressed migration and invasion in RCC cells. The ectopic expression of DIRAS1 via an expression vector recapitulated the RNAa results. These results reveal that DIRAS1, functioning as a putative tumor suppressor in RCC cells, could potentially be a therapeutic target and RNAa could be a therapeutic strategy for RCC.

HMGB1/RAGE axis mediates the apoptosis, invasion, autophagy, and angiogenesis of the renal cell carcinoma

BackgroundHigh mobility group box 1 protein (HMGB1) is a sort of non-histone protein in chromatin, which plays an important role in tumor proliferation, invasion, and immune escape. HMGB1-RAGE (receptor for advanced glycation end products) interactions have been reported to be important in a number of cancers.MethodsCCK8, flow cytometry and qRT-PCR were used to detected cell viability, apoptosis and gene expression, respectively.ResultsIn the present study, we demonstrated that HMGB1/RAGE axis regulated the cell proliferation, apoptosis, and invasion of the renal cell carcinoma (RCC). Further, we discovered that HMGB1/RAGE axis increased the expression of autophagic proteins LC3 and Beclin-1 in RCC. Finally, we used a coculture model of human umbilical vein endothelial cells with RCC cell lines to find out that HMGB1 also increased the expression of VEGF and VEGFR2 in human umbilical vein endothelial cells. An in vivo study further confirmed that HMGB1 knockdown inhibited RCC tumor growth.ConclusionOur results illustrated that HMGB1/RAGE axis mediated RCC cell viability, apoptosis, invasion, autophagy, and angiogenesis, which provides a novel theoretical basis for using HMGB1 as the target in RCC.