Renal Cell Carcinoma Cell Viability Research Articles

Poria acid inhibit the growth and metastasis of renal cell carcinoma by inhibiting the PI3K/akt/NF-κb signaling pathway

BackgroundPoria acid (PAC) is a triterpene compound found in Poria cocos, a traditional Chinese medicine (TCM). The current study aims to explore the therapeutic effects and potential mechanisms of PAC on the migration and proliferation of human renal cell carcinoma (RCC) cells as well as tumor growth in animal model. MethodsCell viability and proliferative capacity of normal renal cells and RCC cells were investigated by MTT assay. In addition, 786-O cells were divided into four groups and treated with different concentrations of PAC (0, 20, 40, and 60 μM) for 48 h. Cell scratch test and cell invasion assay were performed to evaluate the effects of PAC on the invasion and migration of RCC cells, respectively. The effects of PAC on apoptosis of RCC cells and expression levels of PI3K/Akt/NF-kB signaling pathway-related biomarkers were investigated using TUNEL staining and Western blotting methods, respectively. Effects of PAC on the inhibitory activity of RCC tumor in mice were evaluated in a 786-O CDX model. ResultsThe study found that PAC inhibited the viability of RCC cells in a dose-dependent manner, as demonstrated by in vitro cell assays (p < 0.05). However, PAC showed no significant inhibitory effect on normal renal cells (p > 0.05). PAC also significantly inhibited the migration and invasion of RCC via EMT/MMP signaling pathways (p < 0.05). Immunofluorescence and immunoblotting results showed that PAC induced the apoptosis of RCC, which was accompanied by changes in the expression levels of apoptosis-related proteins (p < 0.05). Moreover, PAC significantly downregulated the PI3K/Akt/NF-kB signaling pathway in a concentration-dependent manner (p < 0.05). The effect of PAC on RCC apoptosis was dramatically reversed by 740Y–P (PI3K agonist) (p < 0.05) but significantly enhanced in the presence of LY294002 (PI3K inhibitor) (p < 0.05). The results of in vivo experiment also demonstrated that the antitumor activity of PAC was achieved by affecting the PI3K/Akt/NF-kB signaling pathway. ConclusionsPAC can effectively suppress the proliferation, invasion and migration of RCC cells, and exhibit anti-tumor effects in RCC model by inhibiting the PI3K/Akt/NF-kB signaling pathway.

Ropivacaine suppresses the progression of renal cell carcinoma through regulating the lncRNA RMRP/EZH2/CCDC65 axis.

Renal cell carcinoma (RCC) is a common malignancy. Local anesthetics were displayed powerful effects against various cancers. This study aims to probe the functions and molecular mechanism of ropivacaine in RCC. Different concentrations of ropivacaine were performed to administrate RCC cells including 786-O and Caki-1 cells. Cell viability and cell apoptosis were examined using CCK-8 and flow cytometry, respectively. Cell migration and invasion were determined by transwell assay. RMRP and CCDC65 expression was firstly predicted using TCGA dataset and further validated in RCC cells using qRT-PCR and western blot. The interactions among RMRP, EZH2 and CCDC65 were verified by RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP) assays. Ropivacaine effectively suppressed RCC cell viability, migration and invasion and enhanced cell apoptosis rate. Aberrantly elevated RMRP expression in RCC tissues was predicted by TCGA database. Interestingly, overexpressed RMRP observed in RCC cells could be also blocked upon the administration of ropivacaine. Likewise, RMRP knockdown further strengthened ropivacaine-mediated tumor suppressive effects on RCC cells. In terms of mechanism, RMRP directly interacted with EZH2, thereby modulating the histone methylation of CCDC65 to silence its expression. Moreover, ropivacaine inhibited tumor growth in mice bearing RCC tumor through regulating RMRP/EZH2/CCDC65 axis. In sum up, our work revealed that ropivacaine suppressed capacities of RCC cell viability, migration and invasion through modulating the RMRP/EZH2/CCDC65 axis, which laid the experimental foundation of ropivacaine for clinical application in the future.

Venetoclax Synergizes Sunitinib in Renal Cell Carcincoma through Inhibition of Bcl-2.

More effective treatment options for patients with renal cell carcinoma (RCC) are needed, in particular advanced RCC. Sunitinib, a multitarget tyrosine kinase inhibitor, is a first-line treatment of metastatic RCC. However, the management of sunitinib-induced adverse events and resistance is complex. In hematological malignancies, effective targeting of anti-apoptotic proteins such as Bcl-2 has been achieved, but limited progress has been made in solid tumors. This work systematically investigated the therapeutic potential of the combination of sunitinib and venetoclax, a Bcl-2 inhibitor, in preclinical RCC models. Quantitative analysis of drug interactions was performed. Cell viability was examined after drug treatment or Bcl-2 siRNA depletion. RCC xenograft mouse model was applied to validate the efficacy of sunitinib and venetoclax. A strong synergistic interaction between sunitinib and venetoclax was observed across a range of different dose levels in all tested RCC cell lines. Sequential treatment studies show that the sequential addition of venetoclax and then sunitinib is superior to concurrent treatment and the sequential addition of sunitinib and then venetoclax in decreasing RCC cell viability. The sensitivity of RCC cell lines to venetoclax treatment negatively correlates with their Bcl-2 levels. Specific depletion of Bcl-2 mimics the synergistic effects of venetoclax with sunitinib. Treatment of mice implanted with high Bcl-2-expressing RCC cells reveals that a combination of venetoclax and sunitinib at a non-toxic dose displays complete regression of tumor growth throughout the whole duration of treatment. Our work demonstrates that inhibiting Bcl-2 by venetoclax synergistically enhances sunitinib's efficacy in RCC. Venetoclax holds great potential as a viable option for clinical use.

Enhanced synergy of pacritinib with temsirolimus and sunitinib in preclinical renal cell carcinoma model by targeting JAK2/STAT pathway

Pacritinib is an oral medication that inhibits several kinases including JAK2, FLT3, IRAK and STAT3. It has been recently approved to treat patients with thrombocytopenia and myelofibrosis. Studies are currently exploring the potential use of pacritinib in treating other types of cancer such as leukaemia, breast cancer and prostate cancer. Our study aimed to investigate the effects of pacritinib alone and its combination with standard of care in renal cell carcinoma (RCC). We showed that pacritinib dose-dependently decreased viability of RCC cells, with IC50 at nanomolar or low micromolar concentration rage. Pacritinib inhibited cell proliferation, decreased colony formation, and increased apoptosis. Interestingly, pacritinib exhibited synergistic effects when combined with temsirolimus and sunitinib, but antagonistic effects when combined with doxorubicin, in a panel of RCC cell lines. We also confirmed that the combination of pacritinib with temsirolimus and sunitinib resulted in synergistic effects in RCC mouse models, with complete inhibition of tumour growth throughout the treatment period. Mechanistic studies indicated that the inhibition of JAK2, but not IRAK, was the main contributor to the anti-RCC activity of pacritinib. Our study is the first to demonstrate that pacritinib shows promise as a treatment option for RCC and underscores the therapeutic potential of targeting the JAK2/STAT signalling pathway in RCC.

Overcoming the compensatory increase in NRF2 induced by NPL4 inhibition enhances disulfiram/copper-induced oxidative stress and ferroptosis in renal cell carcinoma

Renal cell carcinoma (RCC) is the most common type of kidney cancer, and it appears to be highly susceptible to ferroptosis. Disulfiram, an alcoholism drug, has been shown to have anticancer properties in various studies, including those on RCC. However, the mechanism of the anticancer effect of disulfiram/copper on RCC remains unclear. In this study, we investigated the impact of disulfiram/copper on RCC treatment using both RCC cells and mouse subcutaneous tumor models. Our findings demonstrate that disulfiram/copper treatment reduced the viability of RCC cells, inhibited their invasion and migration, and disrupted mitochondrial homeostasis, ultimately leading to oxidative stress and ferroptosis. Mechanistically, disulfiram/copper treatment prolonged the half-life of NRF2 and reduced its degradation, but had no effect on transcription, indicating that the disulfiram/copper-induced increase in NRF2 was not related to transcription. Furthermore, we observed that disulfiram/copper treatment reduced the expression of NPL4, a ubiquitin protein-proteasome system involved in NRF2 degradation, while overexpression of NPL4 reversed NRF2 levels and enhanced disulfiram/copper-induced oxidative stress and ferroptosis. These results suggest that overcoming the compensatory increase in NRF2 induced by NPL4 inhibition enhances disulfiram/copper-induced oxidative stress and ferroptosis in RCC. In addition, our in vivo experiments revealed that disulfiram/copper synergized with sorafenib to inhibit the growth of RCC cells and induce ferroptosis. In conclusion, our study sheds light on a possible mechanism for disulfiram/copper treatment in RCC and provides a potential synergistic strategy to overcome sorafenib resistance.

CircZBTB44 promotes renal carcinoma progression by stabilizing HK3 mRNA structure

CircZBTB44 (hsa_circ_0002484) has been identified to be upregulated in renal cell carcinoma (RCC) tissues, while its role and contribution in RCC remain elusive. We confirmed the overexpression of circZBTB44 in RCC cells compared to normal kidney cell HK-2. CircZBTB44 knockdown suppressed the viability, proliferation, and migration of RCC cells and inhibited tumorigenesis in xenograft mouse models. Heterogeneous Nuclear Ribonucleoprotein C (HNRNPC) and Insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) are two RNA binding proteins of circZBTB44. HNRNPC facilitated the translocation of circZBTB44 from nuclei to cytoplasm via m6A modification, facilitating the interaction of IGF2BP3 and circZBTB44 in the cytoplasm of RCC cells. Furthermore, circZBTB44 upregulated Hexokinase 3 (HK3) expression by binding to IGF2BP3 in RCC cells. HK3 exerted oncogenic effects on RCC cell malignant behaviors and tumor growth. In the co-culture of RCC cells with macrophages, circZBTB44 promoted M2 polarization of macrophages by up-regulating HK3. In summary, HNRNPC mediated circZBTB44 interaction with IGF2BP3 to up-regulate HK3, promoting the proliferation and migration of RCC cells in vitro and tumorigenesis in vivo. The results of the study shed new light on the targeted therapy of RCC.

Zinc Oxide Nanoparticle Inhibits Tumorigenesis of Renal Cell Carcinoma by Modulating Lipid Metabolism Targeting miR-454-3p to Repressing Metabolism Enzyme ACSL4.

Background Renal cell carcinoma (RCC) affects the life quality of patients with advanced diseases despite good prognosis and exhibits abnormal lipid metabolism. Zinc oxide nanoparticles (ZONs) are metal oxide nanoparticles that are regarded as promising therapeutic candidate for multiple diseases. This study was for exploring the function of ZONs in RCC. Methods We established in vitro cell model and in vivo xenograft model to determine the antitumor effect of ZONs. Cell viability and proliferation were evaluated via the cell counting kit-8 (CCK-8), colony formation, and 5-ethynyl-2'-deoxyuridine (EDU) assay. Protein and RNA levels were checked by using immunohistochemistry (IHC) and qRT-PCR assay. ROS, malondialdehyde (MDA), triglyceride, and total cholesterol were quantified to assess lipid oxidation and synthesis. Oil red O staining was performed to check lipid droplets accumulation. The ACSL4 and miR-454-3p expression in tumor samples and normal tissues were evaluated. The luciferase reporter gene assay was performed for checking the interaction between miR-454-3p and ACSL4 3'UTR region. Results ZONs suppressed the proliferation and viability of RCC cells both in vitro and in vivo. ZONs suppressed accumulation of ROS, MDA, triglyceride, total cholesterol, and lipid droplets in RCC cells, along with upregulated miR-454-3p. miR-454-3p targeted the 3'UTR region to suppress its expression. In patient samples, ACSL4 expression was notably elevated and indicated poor prognosis of RCC patients. Conclusion ZONs treatment notably impeded proliferation, lipid accumulation, and oxidation in RCC cells, through upregulating miR-454-3p to suppression the function of ACSL4. Our data suggested that ZONs are promising and effective agent for RCC treatment.

Long Noncoding RNA MMP2-AS1 Contributes to Progression of Renal Cell Carcinoma by Modulating miR-34c-5p/MMP2 Axis.

Renal cell carcinoma (RCC) serves as a prevalent malignancy of urinary system and presents severe mortality and increasing incidence. Long noncoding RNAs (lncRNAs) have demonstrated critical roles in RCC development. Here, we were interested in the function of MMP2-AS1 during RCC progression. We observed that MP2-AS1 localized in both nucleus and cytoplasm of RCC cells using fluorescent in situ hybridization (FISH). The cell viability, proliferation, invasion, and migration of RCC cells were reduced by the depletion of MMP2-AS1. The MMP2-AS1 depletion-inhibited viability, proliferation, migration, and invasion of RCC cells were rescued by the overexpression of MMP2 in vitro. Consistently, the tumor growth of RCC cells was repressed by the depletion of MMP2-AS1 in the nude mice, while the overexpression of MMP2 could reverse this effect in vivo. Mechanically, we predicted the potential interaction of miR-34c-5p with both MMP2-AS1 and MMP2. The treatment of miR-34c-5p mimic reduced the luciferase activity of MMP2-AS1 and MMP2 3′UTR. The depletion of MMP2-AS1 enhanced miR-34c-5p expression and the expression of MMP2 was inhibited by miR-34c-5p in RCC cells. The protein levels of MMP2 were downregulated by MMP2-AS1 knockdown, while the inhibitor of miR-34c-5p rescued the expression of MMP2 in the cells. The treatment of miR-34c-5p mimic attenuated the cell viability, proliferation, invasion, and migration of RCC cells, in which MMP2 overexpression restored the phenotypes. MMP2-AS1 depletion-attenuated viability, proliferation, migration, and invasion of RCC cells were reversed by miR-34c-5p inhibitor. We concluded that MMP2-AS1 contributed to progression of renal cell carcinoma by modulating miR-34c-5p/MMP2 axis.

CX3CL1 in the red bone marrow promotes renal cell carcinoma to metastasize to the spine by involving the Src-related pathway.

Spinal metastasis (SM) frequently occurs in renal cell carcinoma (RCC) patients. Our preliminary work showed that CX3CL1 plays a positive role in SM. The objective of the present study was to verify whether CX3CL1 activates the downstream pathway by binding to CX3CR1 in RCC cells, ultimately promoting RCC to metastasize to the spine. The expression of CX3CL1 and CX3CR1 in tissue samples was detected by immunohistochemistry and western blotting. ELISA was used to quantify the concentration of CX3CL1 in the serum. The expression level of CX3CR1 in RCC cell lines was also detected. The CellTiter-Glo assay and flow cytometry were used to analyze cell viability and apoptosis of RCC cells. Transwell and wound healing assay were used to analyze the effect of CX3CL1 on the invasion and migration ability of RCC cells. Specific inhibitors were used to interfere with key molecules in the signaling pathway to further explore the signal transduction in RCC cells after CX3CL1 stimulation. The expression of CX3CR1 in SM from RCC was higher than that in limb bone metastases. Among the five RCC cell lines, 786O cells expressed the highest level of CX3CR1. CX3CL1 neither inhibited the proliferation of 786O cells nor promoted the apoptosis of 786O cells. However, it promoted the migration and invasion of RCC cells. After CX3CL1 stimulation, Src and Focal adhesion kinase (FAK) phosphorylation levels increased in RCC cells. Bosutinib and PF-00562271 inhibited Src/FAK phosphorylation and cell motility and invasion triggered by CX3CL1 stimulation. CX3CL1 in the red bone marrow of spinal cancellous bone enhances migration and invasion abilities of RCC cells, thereby promoting RCC metastasize to the spine. The migration and invasion of RCC cells activated by CX3CL1 are at least partially dependent on Src/FAK activation.

PAPP-A functions as a tumor suppressor and is downregulated in renal cell carcinoma.

Pregnancy‐associated plasma protein A (PAPP‐A) is a proteolytic enzyme produced by the placenta. The expression and role of PAPP‐A in renal cell carcinoma (RCC) remain elusive. The aim of this study was to investigate the role and the molecular mechanisms of PAPP‐A in RCC. Initially, we evaluated the expression of PAPP‐A in samples from patients with RCC and cell lines by quantitative PCR, western blot and immunohistochemical staining, and examined the role of PAPP‐A in RCC cells by cell viability, colony formation and Transwell assays. Next, we investigated the molecular mechanisms regulating the tumor suppressor function of PAPP‐A. Our results demonstrated that PAPP‐A is expressed at low levels in RCC tissues and cells. Clinical data analysis revealed a significant correlation between PAPP‐A expression and RCC‐related death (P < 0.0115). Overexpression of PAPP‐A inhibited viability, proliferation, migration and invasion of RCC cells. Furthermore, PAPP‐A overexpression significantly increased phosphorylation of c‐Jun N‐terminal kinase and decreased the expression of cyclin D1, phosphorylated glycogen synthase kinase‐3β and β‐catenin. This study is the first to report that downregulation of PAPP‐A is associated with poor prognosis in patients with RCC. In conclusion, PAPP‐A may serve as a novel prognostic marker and potentially as a therapeutic target in patients with RCC.

Simvastatin suppresses renal cell carcinoma cells by regulating DDX5/DUSP5

Objectives Renal cell carcinoma (RCC) has the highest mortality rate of genitourinary cancers and the incidence of RCC has risen steadily. Simvastatin has been reported to exhibit anti-tumor activity in a variety of cancers; however, its roles and molecular mechanisms in RCC remain unclear. Our aim was to evaluate the inhibitory effect of simvastatin on RCC. Methods We used a variety of methods to test the changes of RCC cell lines’ viability, migration, invasion, cell cycle and apoptosis after treatment with simvastatin. Results We found that simvastatin not only inhibited RCC cell viability, migration, and invasion, but also regulated the cell cycle and induced apoptosis. We also observed abnormal expression of DDX5 and DUSP5 in RCC cell lines. Mechanistic investigation showed that simvastatin significantly suppressed DDX5 and promoted DUSP5 expression. Conclusion Together, these results provide a novel mechanism underlying simvastatin-induced inhibition of RCC via regulation of the DDX5/DUSP5 axis.

Suppressive effects of RASAL2 on renal cell carcinoma via SOX2/ERK/p38 MAPK pathway.

Metastatic renal cell carcinoma (RCC) is associated with poor prognosis. Ras protein activator like 2 (RASAL2) protein has been previously demonstrated to serves as a tumor suppressor in a variety of malignancies. Therefore, the aim of the present study was to investigate the role of RASAL2 in RCC. Reverse transcription-quantitative PCR, western blot analysis and immunohistochemistry were performed to measure mRNA and protein expression in RCC tissues, whilst immunofluorescence and western blotting were performed to evaluate protein expression in RCC cells. A Cell Counting Kit-8 and 5-bromo-2'-deoxyuridine staining were applied to determine cell viability, and Transwell assays were conducted to measure RCC cell invasion and migration. RASAL2 expression was identified to be downregulated in RCC tissues, which associate negatively with RCC pathological grade. Sox2 expression, in addition to ERK1/2 and p38 MAPK phosphorylation, were demonstrated to be increased in RCC tissues. In RCC cells, RASAL2 overexpression decreased the expression of Sox2 and the activation of ERK1/2 and p38 MAPK. Physiologically, RASAL2 overexpression decreased RCC cell viability, invasion and migration. The expression of metalloproteinase-2/9 and tissue inhibitor of metalloproteinase 1 were also identified to be decreased and increased by RASAL2 overexpression, respectively. By contrast, RASAL2 knockdown exerted opposite effects on RCC cells compared with those observed following RASAL2 overexpression. RASAL2 expression decreased RCC cell viability, migration and invasion, which was demonstrated to be associated with the inactivation of SOX2/ERK1/2/p38 MAPK signaling. These results suggest that RASAL2 may potentially serve as a potential target for the development of novel therapeutic intervention strategies against RCC.

LINC02738 Participates in the Development of Kidney Cancer Through the miR-20b/Sox4 Axis.

BackgroundLong non-coding RNAs (lncRNAs) can affect tumorigenesis. Data from The Cancer Genome Atlas (TCAG) suggest that LINC02783 is highly expressed in renal cell carcinoma (RCC) and is expected to be a potential biological target. We conducted this study to verify this.Patients and MethodsWe conducted this study to verify the opinion that “LINC02783 is highly expressed in renal cell carcinoma (RCC) and is expected to be a potential biological target”. We employed quantitative real-time polymerase chain reaction (qRT-PCR) to test LINC02783 expression in RCC tissues, CKK-8 assay and transwell assay to assess the viability and invasion of RCC cells, Western blot to quantify Sox-4 expression, dual-luciferase reporter (DLR) assay and RNA immunoprecipitation (RIP) assay to analyze the interaction between LINC02783 and miR-20b, in vivo experiments to test tumor formation.ResultsWe detected high LINC02783 expression in RCC patients. Patients with higher LINC02783 levels had a markedly poorer prognosis. In vitro and in vivo, the down-regulation of LINC02783 suppressed the viability and invasion of RCC cells. The DLR assay results revealed that LINC02783 enhanced Sox-4 expression by regulating miR-20b. LINC02783 can act as a sponge for miR-20b to inhibit Sox-4 expression.ConclusionLINC02783 is highly expressed in RCC patients and indicates a poor prognosis. LINC02783 can affect the occurrence and progression of RCC through the miR-20b/Sox-4 axis, making it a promising target for the treatment of RCC.

MiR-4461 Inhibits Tumorigenesis of Renal Cell Carcinoma by Targeting PPP1R3C.

Background: Renal cell carcinoma (RCC) is one of the most common and malignant tumors in the urinary system. The aim of this research was to investigate the mechanism and clinical significance of miR-4461 in the RCC progression. Materials and Methods: Twenty-eight (28) paired RCC tissue samples and adjacent nontumor tissue samples, as well as RCC cell lines were used to measure the expression of miR-4461 and protein phosphatase 1 regulatory subunit 3C (PPP1R3C) transcript by real-time quantitative PCR. The target relationship between miR-4461 and PPP1R3C was predicted by TargetScan and further verified by dual-luciferase reporter gene assay and RNA pull-down assay. Cell Counting Kit-8 (CCK-8) assay and BrdU ELISA assay were performed to measure RCC cell viability and proliferation. In addition, caspase-3 activity assay and cell adhesion assay were implemented to measure RCC cell apoptosis and adhesion. Results: MiR-4461 was lowly expressed both in RCC tissues and cells, while upregulated PPP1R3C was tested in RCC tissues and cells. In addition, miR-4461 was validated to directly target PPP1R3C, thereby negatively regulating PPP1R3C. Particularly, miR-4461 exerted a clear inhibitory effect on the malignant phenotypes of RCC cells by binding and inhibiting PPP1R3C. Conclusion: MiR-4461, which served as a tumor suppressor, inhibited RCC progression by targeting and downregulating PPP1R3C.

TBOPP enhances the anticancer effect of cisplatin by inhibiting DOCK1 in renal cell carcinoma

The treatment of renal cell carcinoma (RCC) with chemotherapy remains a challenge; therefore, improving the knowledge of the molecular mechanisms underlying RCC chemoresistance and developing novel therapeutic strategies is important. Dedicator of cytokinesis 1 (DOCK1), the first member of the DOCK family to be discovered, displays various roles during tumorigenesis; however, its role during RCC progression is not completely understood. Therefore, the present study aimed to clarify the function of DOCK1 and 1-[2-(3′-(trifluoromethyl)-(1,1′-biphenyl)-4-yl)-2-oxoethyl]-5-pyrrolidinylsulfonyl-2 (1H)-pyridone (TBOPP), a DOCK1-sensitive inhibitor, during RCC development and chemoresistance. The results of CCK-8 and EdU assay indicated that TBOPP decreased RCC cell viability and proliferation compared with the control group, and sensitized RCC cells to cisplatin. Moreover, RCC cells with high DOCK1 expression levels displayed increased resistance to cisplatin, whereas DOCK1 knockdown enhanced the lethal effects of cisplatin on RCC cells. Furthermore, the results determined by western blotting, CCK-8 and cell apoptosis assay indicated that TBOPP effectively reduced DOCK1 expression levels compared with the control group, and the TBOPP-mediated cisplatin sensitizing effect was mediated by DOCK1 inhibition. The present study suggests that DOCK1 plays a vital role in RCC cell chemoresistance to cisplatin; therefore, TBOPP may serve as a novel therapeutic agent for RCC chemoresistance.

LncRNA RP11-567G11.1 accelerates the proliferation and invasion of renal cell carcinoma through activating the Notch pathway.

In recent years, the death number of renal cell carcinoma (RCC) has been enhanced annually. The crucial function of long non-coding RNA (lncRNA) in the occurrence and progression of cancer is of great significance. However, the specific role of lncRNAs in the pathogenesis and prognosis of RCC has not been fully elucidated. Therefore, the aim of this study was to uncover the role of lncRNA RP11-567G11.1 in regulating the progression of RCC. Relative expression level of RP11-567G11.1 in RCC tissues and cells was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The influences of RP11-567G11.1 on proliferative and invasive abilities of RCC cells were assessed. Subsequently, regulatory effects of RP11-567G11.1 on the viability and apoptosis of DDP-induced RCC cells were examined. Furthermore, the mRNA and protein levels of Notch pathway-related genes Jagged1/HES5/HEY1 in RCC were detected by qRT-PCR and Western blot, respectively. RP11-567G11.1 expression was significantly up-regulated in RCC tissues and cells. Meanwhile, RP11-567G11.1 was highly expressed in RCC patients with advanced stage. Knockdown of RP11-567G11.1 significantly attenuated proliferative and invasive abilities of 786-O and 769-P cells. Silence of RP11-567G11.1 attenuated viability, while it induced apoptosis in DDP-induced RCC cells. In addition, knockdown of RP11-567G11.1 remarkably down-regulated both mRNA and protein levels of Jagged1, HES5, and HEY1 in RCC. RP11-567G11.1 accelerates the proliferative and invasive abilities of RCC through activating the Notch pathway. Our findings suggest that it may be a new therapeutic target for RCC.

Ginkgolic acid inhibits the growth of renal cell carcinoma cells via inactivation of the EGFR signaling pathway.

Renal cell carcinoma (RCC) is one of the most common urological malignancies occurring in adult human kidneys worldwide. Recent research on antitumor drugs has focused on plant extracts, a class of compounds that play critical roles in cancer treatment. The present study aimed to investigate the potential antitumor effect of ginkgolic acid (GA) in RCC. Transwell invasion assay, cell counting kit-8 assay and flow cytometry were used to measure cell migration, cell viability and apoptosis, respectively. A network pharmacology approach was applied to identify pathway information, combining molecular docking techniques to screen for key target information. In the present study, GA inhibited the viability and proliferation of RCC cells (786-O and A498), both in vitro and in vivo, via G1 arrest. GA also reduced RCC cell invasion and migration. In addition, the epidermal growth factor receptor (EGFR) was identified as a critical target protein of GA, which significantly inactivated EGFR signaling in RCC (P<0.05). Collectively, the present study provided evidence that GA exerts its anticancer function by directly targeting the EGFR signaling pathway, revealing the potential of GA therapy for RCC.

VHL enhances 9-cis-retinoic acid treatment by down-regulating retinoid X receptor α in renal cell carcinomas

Renal cell carcinoma (RCC) is the most common malignant kidney tumors in adults. Von Hippel-Lindau (VHL) gene is deficient in >50% of RCC cases, but the role of VHL as a potential therapeutic target in RCC has not been well established. In the present study, 9-cis-Retinoic acid, which is a potent natural agonist of retinoid X receptors (RXRs), was found to decrease the viability of VHL-proficient RCC cells, but had little effect on VHL-deficient RCC cells. In addition, it was demonstrated that VHL transcriptionally regulated RXRα in a hypoxia-inducible factor-α independent manner. Moreover, a negative correlation was observed between the expressions of VHL and RXRα in RCC tissues. Collectively, these data indicate that VHL-proficient RCC patients may be more sensitive to treatment with 9-cis-retinoic acid, which acts by regulating RXRα expression, compared with VHL-deficient RCC patients. The findings of the present study demonstrate a novel function of VHL and highlight the potential of VHL expression as a therapeutic modality for the optimized treatment of RCC patients.

Hypoxia-responsive miR-346 promotes proliferation, migration, and invasion of renal cell carcinoma cells via targeting NDRG2.

Renal cell carcinoma (RCC) is the most common malignant tumor of the kidney. In this study, we investigated the role of miR-346 in RCC cells under hypoxia. OS-RC-2 and 786-O cells were cultured in 1% O2 or normal oxygen. Cell proliferation, migration, and invasion abilities were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, transwell migration, and invasion assays, respectively. Quantitative real-time PCR (qRT-PCR) was performed to detect the expression of miR-346 and N-myc downstream-regulated gene 2 (NDRG2). Then bioinformatics analysis, dual-luciferase reporter assay, and RNA immunoprecipitation were carried out to determine the relationship between miR-346 and NDRG2. The protein expression of NDRG2 was detected by western blot assay. Hypoxia promoted cell proliferation, migration, and invasion in OS-RC-2 and 786-O cells. Meanwhile, we found that miR-346 was upregulated in RCC cells under hypoxia as relative to normoxia. miR-346 deletion could decrease the viability, migration, and invasion abilities of RCC cells under hypoxia. Besides, our data demonstrated that NDRG2 was a target gene of miR-346. The expression of NDRG2 in OS-RC-2 and 786-O cells was lower under hypoxia than under normal oxygen conditions. Moreover, NDRG2 overexpression could inhibit cell proliferation, migration, and invasion in RCC cells under hypoxia. And NDRG2 silencing reversed the inhibitory effects of the miR-346 inhibitor on the viability, migration, and invasion abilities of RCC cells in hypoxia conditions. miR-346 promoted the viability, migration, and invasion of RCC cells under hypoxia by targeting NDRG2.

PLEKHO1 knockdown inhibits RCC cell viability in vitro and in vivo, potentially by the Hippo and MAPK/JNK pathways.

Renal cell carcinoma (RCC) is the most common type of kidney cancer. By analysing The Cancer Genome Atlas (TCGA) database, 16 genes were identified to be consistently highly expressed in RCC tissues compared with the matched para-tumour tissues. Using a high-throughput cell viability screening method, it was found that downregulation of only two genes significantly inhibited the viability of 786-O cells. Among the two genes, pleckstrin homology domain containing O1 (PLEKHO1) has never been studied in RCC, to the best of our knowledge, and its expression level was shown to be associated with the prognosis of patients with RCC in TCGA dataset. The upregulation of PLEKHO1 in RCC was first confirmed in 30 paired tumour and para-tumour tissues. Then, the effect of PLEKHO1 on cell proliferation and apoptosis was assessed in vitro. Additionally, xenograft tumour models were established to investigate the function of PLEKHO1 in vivo. The results showed that PLEKHO1 knockdown significantly inhibited cell viability and facilitated apoptosis in vitro and impaired tumour formation in vivo. Thus, PLEKHO1 is likely to be associated with the viability of RCC cells in vitro and in vivo. Further gene expression microarray and co-expression analyses showed that PLEKHO1 may be involved in the serine/threonine-protein kinase hippo and JNK signalling pathways. Together, the results of the present study suggest that PLEKHO1 may contribute to the development of RCC, and therefore, further study is needed to explore its potential as a therapeutic target.