Adjacent Normal Renal Tissues Research Articles

ERBB2 is a potential diagnostic and prognostic biomarker in renal clear cell carcinoma

Renal clear cell carcinoma (ccRCC) is a common parenchymal tumor of the kidney, and the discovery of biomarkers for early and effective diagnosis of ccRCC can improve the early diagnosis of patients and thus improve long-term survival. Erb-b2 receptor tyrosine kinase 2 (ERBB2) mediates the processes of cell proliferation, differentiation, and apoptosis inhibition. The purpose of this study was to investigate the diagnostic and prognostic role of ERBB2 in ccRCC. We analyzed the expression levels of ERBB2 in various cancers from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. RNA-seq data were analyzed using R packages to identify differentially expressed genes between the high and low ERBB2 expression groups in the TCGA-KIRC dataset. Spearman correlation analysis was performed to determine the correlation between ERBB2 expression and immune cell infiltration, immune checkpoint expression, and PTEN expression. DNA methylation changes and genetic alterations in ERBB2 were assessed using the MethSurv and cBioPortal databases. Logistic regression analysis was performed to determine the correlation between ERBB2 expression and the clinicopathological characteristics of ccRCC patients. The diagnostic and prognostic value of ERBB2 was assessed using Kaplan‒Meier (K‒M) survival curves, diagnostic ROC curves, time-dependent ROC curves, nomogram models, and Cox regression models. The expression level of ERBB2 is lower in tumor tissues of ccRCC patients than in the corresponding control tissues. Differentially expressed genes associated with ERBB2 were significantly enriched in the pathways “BMP2WNT4FOXO1 pathway in primary endometrial stromal cell differentiation” and “AMAN pathway”. In ccRCC tissues, ERBB2 expression levels were associated with immune cell infiltration, immune checkpoints, and PTEN. The DNA methylation status of 10 CpG islands in the ERBB2 gene was associated with the prognosis of ccRCC. ERBB2 expression levels in ccRCC tissues were associated with race, sex, T stage, M stage, histological grade, and pathological stage. Cox regression analysis showed that ERBB2 was a potential independent predictor of overall survival (OS), disease-specific survival (DSS), and progression-free interval (PFI) in ccRCC patients. ROC curve analysis showed that the expression level of ERBB2 could accurately distinguish between ccRCC tissue and adjacent normal renal tissue. Our study showed that ERBB2 expression in ccRCC tissues can be of clinical importance as a potential diagnostic and prognostic biomarker.

HADH suppresses clear cell renal cell carcinoma progression through reduced NRF2-dependent glutathione synthesis

BackgroundClear cell renal cell carcinoma (ccRCC) is a serious threat to human life. It is very important to clarify the pathogenesis of ccRCC. In this study we evaluated the clinical value of HADH and explored its role and mechanism in the malignant progression of ccRCC. MethodsHADH expression and its relationship with prognosis were analyzed using bioinformatics database. RT-PCR, Western blot and immunohistochemistry were used to examine the expression of HADH in ccRCC tissues and tissue microarrays. To examine the cell proliferation, apoptosis, migration and invasion ability, ccRCC cells with HADH overexpressed were constructed. Xenograft experiments were performed to determine the role of HADH. Non-target metabolomics was applied to explore the potential metabolic pathway by which HADH inhibited ccRCC progression. Plasmid pcDNA3.1-NRF2 was used to confirm whether HADH inhibited the process of ccRCC cells through NRF2-related glutathione (GSH) synthesis. ResultsBioinformatics database analysis showed that HADH expression was significantly decreased in ccRCC tissues, and its low expression predicted a poor prognosis. Both ccRCC tissues and tissue microarrays exhibited a significantly decreased HADH level compared with adjacent normal renal tissues. HADH overexpression inhibited the malignant behaviors of ccRCC cells. Furthermore, HADH overexpression attenuated GSH synthesis and induced oxidative stress damage. Exogenously increased NRF2 effectively attenuated the inhibitive effect of HADH overexpression on ccRCC cells. ConclusionOur data revealed that HADH suppressed the malignant behaviors of ccRCC cells by attenuating GSH synthesis through inhibition of NRF2 nuclear translocation, and HADH might be a novel therapeutic target for ccRCC treatment.

TIGIT expression in renal cell carcinoma infiltrating T cells is variable and inversely correlated with PD-1 and LAG3

PurposeImmune checkpoint inhibitors have revolutionized the treatment of renal cell carcinoma (RCC), but many patients do not respond to therapy and the majority develop resistant disease over time. Thus, there is increasing need for alternative immunomodulating agents. The co-inhibitory molecule T-cell immunoglobulin and ITIM domain (TIGIT) may play a role in resistance to approved immune checkpoint inhibitors and is being investigated as a potential therapeutic target. The purpose of this study was to quantify TIGIT positivity in tumor-infiltrating T cells in RCC.MethodsWe employed tissue microarrays containing specimens from primary RCC tumors, adjacent normal renal tissue, and RCC metastases to quantify TIGIT within tumor-infiltrating CD3+ T cells using quantitative immunofluorescent analysis. We also compared these results to TIGIT+ CD3+ levels in four other tumor types (melanoma, non-small cell lung, cervical, and head and neck cancers).ResultsWe did not observe significant differences in TIGIT positivity between primary RCC tumors and patient-matched metastatic samples. We found that the degree of TIGIT positivity in RCC is comparable to that in lung cancer but lower than that in melanoma, cervical, and head and neck cancers. Correlation analysis comparing TIGIT positivity to previously published, patient-matched spatial proteomic data by our group revealed a negative association between TIGIT and the checkpoint proteins PD-1 and LAG3.ConclusionOur findings support careful evaluation of TIGIT expression on T cells in primary or metastatic RCC specimens for patients who may be treated with TIGIT-targeting antibodies, as increased TIGIT positivity might be associated with a greater likelihood of response to therapy.

Correlation between methylation of interferon regulatory factor 6 gene promoter in renal tissues and overall survival of patients with Kidney renal clear cell carcinoma

To assess the prognostic value of methylation of interferon regulatory factor 6 (IRF6) gene promoter in patients diagnosed with Kidney renal clear cell carcinoma (KIRC). The primary lesions of fifty KIRC patients who were diagnosed at the First Affiliated Hospital of Nanjing Medical University from January 2016 to January 2020 were collected. The expression of IRF6 protein was determined with an immunohistochemical method. The correlation between the level of IRF6 expression and survival and/or metastasis status was analyzed. The mRNA and protein levels of the IRF6 in KIRC and normal renal tissues were compared by using bioinformatic tools. The difference in the methylation rate of the IRF6 gene promoter between tumor and adjacent tissues was analyzed by searching the online databases. Statistical analysis was carried out for the methylation status of the IRF6 gene promoter region to select those negatively correlated with the overall survival (OS) among the patients. In vitro experiments were conducted with cell lines to verify the correlation between the status of promoter methylation and transcription level of the IRF6 gene. The mRNA and protein levels of the IRF6 gene in KIRC tissues were significantly lower than those of the normal controls, and this was more prominent in patients who had died or developed metastasis. The extent of IRF6 gene promoter methylation in the KIRC tissues was much higher compared with that of the adjacent normal renal tissues. There was a significant negative correlation between the methylation of the IRF6 gene promoter and mRNA level of the IRF6 (R = -0.52). The higher methylation degree in the IRF6 gene promoter regions cg12034118 and cg16030177, the shorter the OS and worse prognosis in the patients. Only twenty CpG sites in cg12034118 were confirmed to be highly methylated in KIRC cell lines. The transcription level of the IRF6 gene was upregulated in a time- and dose-dependent manner after the treatment with demethylation reagent 5-azadeoxycytidine. The methylation of IRF6 gene promoter in the renal tissues of KIRC patients is closely correlated with the OS. Cg12034118 may provide a promising biomarker for laboratory detection, and its high methylation rate has certain reference value for the prognosis.

RUNX1 predicts poor prognosis and correlates with tumor progression in clear cell renal carcinoma

BackgroundRunt-related transcription factor 1 (RUNX1), also called acute myeloid leukaemia 1, is a member of RUNX family of transcription factors. This family is composed of evolutionarily conserved transcription factors that function as critical lineage determinants in various tissues, however its function in cancer development and clinical significance in RCC are still unknown. MethodsWe used paraffin-embedded tumor tissues from 100 patients and fresh-harvested and paired adjacent normal renal tissues from 15 RCC patients who underwent primary surgical resection in Xijing Hospital between 2018 and 2022. The expression level of RUNX1 was evaluated by immunohistochemistry and Western Blot. RUNX1 promoted tumor cells proliferation, migration and invasion were verified by CCK-8, wound-healing and transwell assays. Finally, we constructed a xenografts model of the 786-O cell lines to observe the effect of RUNX1 on tumorigenesis in vivo. ResultsTCGA database showed higher RUNX1 expression levels in KIRC (kidney renal clear cell carcinoma). In overall survival analysis, RCC patients with higher RUNX1 expression level would have a shorter survival period than those with lower expression. Similarly, immunohistochemical results of our cohort also showed that RUNX1 was over-expression in cancer tissues than in corresponding non-cancer tissues. We also proved this result at protein level by western-blot. Meanwhile, prognostic and OS analyses of our cohort showed that the RUNX1 expression level was an individual prognostic factor in RCC patients. CCK-8, wound-healing and transwell assays proved that the overexpression of RUNX1 in Caki-1 cells promoted the proliferation, migration and invasion of the cells. Knocking down RUNX1 in 786-O cells inhibited the proliferation, migration and invasion of cells. The experimental results of xenografts model in nude mice showed that the knockdown of RUNX1 in 786-O cells slowed down the growth of tumor. ConclusionRUNX1 is a poor prognostic factor of clear cell renal carcinoma, which may provide a novel therapeutic target for ccRCC.

A novel prognostic signature for clear cell renal cell carcinoma constructed using necroptosis-related miRNAs

BackgroundThis work aims to analyze the relationship between necroptosis-related microRNAs (miRNAs) and the prognosis of clear cell renal cell carcinoma (ccRCC).MethodsThe miRNAs expression profiles of ccRCC and normal renal tissues from The Cancer Genome Atlas (TCGA) database were used to construct a matrix of the 13 necroptosis-related miRNAs. Cox regression analysis was used to construct a signature to predict the overall survival of ccRCC patients. The genes targeted by the necroptosis-related miRNAs in the prognostic signature were predicted using miRNA databases. Gene Ontology (Go) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were used to investigate the genes targeted by the necroptosis-related miRNAs. The expression levels of selected miRNAs in 15 paired samples (of ccRCC tissues and adjacent normal renal tissues) were investigated using reverse transcriptase quantitative polymerase chain reaction (RT-qPCR).ResultsSix necroptosis-related miRNAs were found to differentially expressed between ccRCC and normal renal tissues. A prognostic signature consisting of miR-223-3p, miR-200a-5p, and miR-500a-3p was constructed using Cox regression analysis and risk scores were calculated. Multivariate Cox regression analysis showed that the hazard ratio was 2.0315 (1.2627–3.2685, P = 0.0035), indicating that the risk score of the signature was an independent risk factor. The receiver operating characteristic (ROC) curve showed that the signature has a favorable predictive capacity and the Kaplan-Meier survival analysis indicated that ccRCC patients with higher risk scores had worse prognoses (P < 0.001). The results of the RT-qPCR verified that all three miRNAs used in the signature were differentially expressed between ccRCC and normal tissues (P < 0.05).ConclusionThe three necroptosis-related-miRNAs used in this study could be a valuable signature for the prognosis of ccRCC patients. Necroptosis-related miRNAs should be further explored as prognostic indicators for ccRCC.

Low EGR1 expression predicts poor prognosis in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is resistant to conventional therapy due to the deletion of the von Hippel-Lindau (VHL) gene, and novel treatment options are urgently needed. Here, using tissue microarray analysis of 445 cancer tissues and 326 adjacent normal renal tissues obtained from patients with ccRCC, we present the early growth response-1 (EGR1) protein levels are significantly decreased in ccRCC cancer tissues. Consistently, the EGR1 mRNA expression also decreased in cancer tissues based on the transcriptomic data for 599 tumor and normal samples from The Cancer Genome Atlas. Moreover, Patients with ccRCC presenting low EGR1 expression are more prone to exhibit metastasis and a poor prognosis than those with high EGR1 expression. By multivariate Cox regression analysis, EGR1 is determined to serve as an independent prognostic factor for patients with ccRCC. Further cellular biochemical function analyses show that EGR1 may inhibit proliferation, invasion and metastasis of ccRCC. These findings will deepen our understanding of EGR1 function and shed light on precise treatment for ccRCC patients.

Siglec-15 promotes progression of clear renal cell carcinoma.

Siglec-15 promotes progression of clear renal cell carcinoma.

USP22 promotes proliferation in renal cell carcinoma by stabilizing survivin.

Renal cell carcinoma (RCC) is one of the commonest urological tumors. The incidence of RCC ranks third among urological tumors, after prostate cancer and bladder tumors. However, the etiology of RCC remains unclear. Ubiquitin-specific protease 22 (USP22), a potential marker of cancer stem cells, is associated with the occurrence and progression of numerous tumors. However, the roles of USP22 in RCC have not yet been investigated. Survivin is a member of the inhibitor of apoptotic protein family involved in RCC progression. The present study first detected the expression of USP22 and survivin in RCC tissues using immunohistochemistry and western blotting. It was revealed that the protein levels of USP22 and survivin in RCC tissues were higher than those in adjacent normal renal tissue. Subsequently, it was demonstrated that USP22 knockdown inhibited the growth of an RCC cell line ACHN and downregulated the protein level of survivin, accompanied by an increased level of cleaved-caspase-3. By contrast, overexpression of USP22 promoted the growth of ACHN cells, upregulated the expression of survivin and decreased the level of cleaved-caspase-3. Notably, the changes in USP22 expression did not affect the SURVIVIN mRNA level. Finally, it was confirmed that USP22 interacted with survivin and stabilized it by downregulating its ubiquitination. The present results indicate that USP22 may regulate survivin via deubiquitination, thereby promoting the proliferation of RCC cells. The results of the current study suggest that USP22 may represent a novel therapeutic target for patients with RCC.

Abstract 1311: Inter- and intra-tumor heterogeneity of genetic and immune profiles in hereditary clear cell renal cell carcinoma

Abstract [Background] Von Hippel-Lindau (VHL) disease is an autosomal dominant hereditary cancer syndrome attributed to germline VHL mutation. Patients with this disease are at risk of developing multiple independent clear cell renal carcinomas (ccRCCs), which offers a unique opportunity to analyze inter- and intra-tumor heterogeneity of genetic and immune profiles in the same patient. [Method] We selected seven patients with clinically diagnosed VHL disease who underwent one or two surgeries, in each of which two to five ccRCC tumors (total, n = 25) were removed. We harvested one to six regions from each tumor (total, n = 48), and performed whole-exome sequencing on them, together with normal blood (n = 7), cyst (n = 3), and adjacent normal renal tissue (n = 7) specimens from these patients. In addition, we carried out RNA-sequencing (for 20 tumors and 3 adjacent tissues) and digital multiplexed gene expression analysis using the NanoString nCounter system with Human Immunology V2 panel (for 36 tumors and 5 adjacent tissues) to clarify their immune profiles. [Result] Germline VHL mutations were confirmed in all seven patients. A total of 1,141 non-silent somatic mutations (8-44 mutations per patient) were detected, including 22 mutations affecting previously reported driver genes (such as BAP1, PBRM1, PTEN, PIK3CA, and SETD2). In consistent with previous reports, tumors arising in this context are clonally independent and harbor distinct secondary events, including mutations and copy number alterations (as exemplified by loss of heterozygosity of 3p). By contrast, multiple specimens from the same tumor showed almost the same genetic alterations, although several subclonal mutations were observed. Unsupervised hierarchical clustering of gene expression data discovered two robust subsets with distinct immune-related signatures. Particularly, the subset with high immune signature (n = 29) showed increased antigen presentation machinery genes (B2M, TAP1 and TAP2) and cytotoxic T lymphocyte genes (CD8, PRF1, and GZMA) than that with low immune signature (n = 19), suggesting a higher cytolytic activity in the former subset. Pathway analysis revealed the enrichment of cytokine interaction, JAK-STAT signaling and Toll-like receptor signaling. Interestingly, specimens from the same tumor invariably showed a similar immune signature, whereas different tumors frequently exhibit different immune signatures despite the identical immune background, suggesting a greater difference of immune status across tumors than within a tumor. [Conclusion] This study delineates inter- and intra-tumor heterogeneity of genetic and immune profiles in hereditary clear cell renal cell carcinoma. Our findings demonstrate more profound inter-tumor than intra-tumor heterogeneity in immune status, suggesting that tumor factors have a greater impact on immune microenvironment than host factors. Citation Format: Mariko Tabata, Yusuke Sato, Yasunori Kogure, Marni B. McClure, Yuji Kumade, Yuki Saito, Sumito Shingaki, Kota Yoshifuji, Junji Koya, Kazushi Yoshida, Takashi Kohno, Kenichi Chiba, Ai Okada, Yuichi Shiraishi, Haruki Kume, Keisuke Kataoka. Inter- and intra-tumor heterogeneity of genetic and immune profiles in hereditary clear cell renal cell carcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1311.

MiR-363 suppresses the proliferation, migration and invasion of clear cell renal cell carcinoma by downregulating S1PR1

BackgroundMicroRNAs (miRNAs) serve as important regulators of the tumorigenesis and progression of many human cancers. Therefore, we evaluated the biological function and underlying mechanism of miR-363 in clear cell renal cell carcinoma (ccRCC).MethodsThe expression of miR-363 in ccRCC tissues compared with adjacent normal renal tissues was detected by quantitative real-time polymerase chain reaction, and the association between miR-363 levels and prognosis of ccRCC patients was analyzed. The candidate target gene of miR-363 was determined by in silico analysis and luciferase reporter assays. The effects of miR-363 on the proliferation, migration and invasion of ccRCC cells in vitro were determined by MTS assay, colony formation assay, Transwell assay and wound healing assay. We also investigated the roles of miR-363 in vivo by a xenograft tumour model. The mechanism of miR-363 on the proliferation, migration and invasion of ccRCC was determined by gain- and loss-of-function analyses.Resultswe demonstrated that miR-363 expression was obviously downregulated in ccRCC tissues and that reduced miR-363 expression was correlated with poor disease-free survival (DFS) in ccRCC patients after surgery. S1PR1 expression was inversely correlated with the level of miR-363 in human ccRCC samples. Luciferase reporter assays suggested that S1PR1 was a direct functional target of miR-363. miR-363 downregulated S1PR1 expression and suppressed the proliferation, migration and invasion abilities of ccRCC cells in vitro and suppressed xenograft tumour growth in vivo. Importantly, miR-363 exerted its biological function by inhibiting S1PR1 expression in ccRCC cells, leading to the repression of ERK activation. Moreover, we found that the levels of downstream effectors of ERK, including PDGF-A, PDGF-B, and epithelial-mesenchymal transition (EMT)-related genes, were decreased after miR-363 overexpression.ConclusionsOur results suggest that miR-363 acts as a tumour suppressor by directly targeting S1PR1 in ccRCC and may be a potential new therapeutic target for ccRCC.

MiR-206 suppresses proliferation and epithelial-mesenchymal transition of renal cell carcinoma by inhibiting CDK6 expression.

Increasing evidence indicates that miRNAs are involved in tumorigenesis of human renal cell carcinoma (RCC). However, the role of miR-206 is still unknown. This study aimed to investigate the possible mechanism of miR-206 in progression of RCC. Here, compared with adjacent normal renal tissues and HK-2 cells, miR-206 level was markedly decreased, whereas CDK6 level was obviously increased in RCC tissues and cell lines. MiR-206 was inversely associated with lymph node metastasis and TNM stage, and acted as an independent prognostic factor in RCC. MiR-206 effectively caused apoptosis and cell cycle arrest at G0/G1 phase, and affected the growth of xenograft tumor of nude mice. MiR-206 also inhibited migration and invasion of RCC cells by modulating the expressions of EMT-related genes. Dual-luciferase assay demonstrated CDK6 was a direct target of miR-206. CDK6 silencing aggravated the inhibition effects of miR-206. In conclusion, miR-206 suppresses proliferation and EMT of RCC by inhibiting CDK6 expression. The miR-206/CDK6 axis may provide a novel insight into tumorigenesis of RCC.

MicroRNA-92b-3p is a prognostic oncomiR that targets TSC1 in clear cell renal cell carcinoma.

Although several studies have reported that microRNA (miR)‐92b‐3p is involved in various cellular processes related to carcinogenesis, its physiological role in clear cell renal cell carcinoma (ccRCC) remains unclear. To clarify the role of miR‐92b‐3p in ccRCC, we compared miR‐92b‐3p expression levels in ccRCC tissues and adjacent normal renal tissues. Significant upregulation of miR‐92b‐3p was observed in ccRCC tissues. Overexpression of miR‐92b‐3p using a miRNA mimic promoted proliferation, migration, and invasion activities of ACHN cells. Functional inhibition of miR‐92b‐3p by a hairpin miRNA inhibitor suppressed Caki‐2 cell growth and invasion activities in vitro. Mechanistically, it was found that miR‐92b‐3p directly targeted the TSC1 gene, a known upstream regulator of mTOR. Overexpression of miR‐92b‐3p decreased the protein expression of TSC1 and enhanced the downstream phosphorylation of p70S6 kinase, suggesting that the mTOR signaling pathway was activated by miR‐92b‐3p in RCC cells. Importantly, a multivariate Cox proportion hazard model, based on TNM staging and high levels of miR‐92b‐3p, revealed that miR‐92b‐3p expression (high vs. low hazard ratio, 2.86; 95% confidence interval, 1.20‐6.83; P = .018) was a significant prognostic factor for overall survival of ccRCC patients with surgical management. Taken together, miR‐92b‐3p was found to act as an oncomiR, promoting cell proliferation by downregulating TSC1 in ccRCC.

ARID1A knockdown triggers epithelial-mesenchymal transition and carcinogenesis features of renal cells: role in renal cell carcinoma.

Down-regulation/mutation of AT-rich interactive domain 1A (ARID1A), a novel tumor suppressor gene, has been reported in various cancers. Nevertheless, its role in renal cell carcinoma (RCC) remained unclear and underinvestigated. We thus evaluated carcinogenesis effects of ARID1A knockdown in nonmalignant Madin-Darby canine kidney (MDCK) renal cells using small interfering RNA (siRNA) against ARID1A (siARID1A). The siARID1A-transfected cells had decreased cell death, increased cell proliferation, and cell cycle shift (from G0/G1 to G2/M) compared with those transfected with controlled siRNA (siControl). Additionally, the siARID1A-transfected cells exhibited epithelial-mesenchymal transition (EMT) shown by greater spindle index, increased mesenchymal markers (fibronectin/vimentin), and decreased epithelial markers (E-cadherin/zonula occludens-1). Moreover, the siARID1A-transfected cells had increases in migratory activity, nuclear size, self-aggregated multicellular spheroid size, invasion capability, chemoresistance (to docetaxel), Snail family transcriptional repressor 1 expression, and TGF-β1 secretion. All of these siARID1A-knockdown effects on the carcinogenic features were reproducible in malignant RCC (786-O) cells, which exhibited a higher degree of carcinogenic phenotypes compared with the nonmalignant MDCK cells. Finally, immunohistochemistry showed obvious decrease in ARID1A protein expression in human RCC tissues (n = 23) compared with adjacent normal renal tissues (n = 23). These data indicate that ARID1A down-regulation triggers EMT and carcinogenesis features of renal cells in vitro, and its role in RCC could be proven in human tissues.-Somsuan, K., Peerapen, P., Boonmark, W., Plumworasawat, S., Samol, R., Sakulsak, N., Thongboonkerd, V. ARID1A knockdown triggers epithelial-mesenchymal transition and carcinogenesis features of renal cells: role in renal cell carcinoma.

The clinical significance of PYCR1 expression in renal cell carcinoma.

Pyrroline-5-carboxylate reductase 1 (PYCR1) is an enzyme involved in cell metabolism and is upregulated in cancer. However, the correlations of PYCR1 expression with the clinicopathological features and prognosis of renal cell carcinoma (RCC) remain unclear. The purpose of this study was to identify the expression of PYCR1 and its clinical relevance in RCC patients.PYCR1 mRNA expression differences between RCC and the adjacent normal renal tissues were assessed using the Cancer Genome Atlas database (TCGA). Subsequently, the expression of PYCR1 mRNA and protein were evaluated by quantitative real-time polymerase chain reaction, Western blot, and immunochemistry using 30 paired frozen samples of RCC and the adjacent normal renal tissues. The protein expression of PYCR1 was evaluated by immunostaining formalin-fixed, paraffin-embedded sections of RCC samples from 96 patients who underwent radical nephrectomy, and its relationship with clinical features were analyzed. Nonpaired t tests were used to statistically analyze the differences between the 2 groups. Cox univariable and multivariable analyses of overall survival (OS) among RCC patients were performed.The expression of PYCR1 mRNA was significantly upregulated in RCC tissues compared to adjacent normal renal tissues in the TCGA database (P < .01). The area under the receiver operating characteristic curve value was 0.748. The expression of PYCR1 mRNA and protein was significantly upregulated in RCC compared with that in paired normal renal tissues (P < .01). Higher PYCR1 levels were associated with metastasis (P < .01). Kaplan–Meier survival curves indicated that higher PYCR1 expression was correlated with poorer OS. Therefore, PYCR1 may act as a novel prognostic marker and therapeutic target in the diagnosis and treatment of RCC.

MiR-106b promotes proliferation and invasion by targeting Capicua through MAPK signaling in renal carcinoma cancer.

Background: miR-106b has been reported to play a vital role in pathogenesis of some types of cancer, whilst the role of miR-106b in renal carcinoma cancer (RCC) remains unknown.Purpose: The objective of this study was to identify the mechanism of miR-106b regulating the progression of renal carcinoma.Method: The expression of miR-106b was analyzed in RCC cell lines, RCC and adjacent normal renal tissues through qRT-PCR assays. Target mRNA of miR-106b was predicted with databases and verified by luciferase reporter assays. And the effects of miR-106b or targeted mRNA on cell proliferation, invasion, the process of epithelial-mesenchymal transitions (EMTs) were assessed in vitrothrough CCK-8, transwell cell invasion assays, qRT-PCR and Western blotting assays respectively. In addition, the effects of miR-106b on the growth of xenografts mice were analyzedin vivo.Results: The results demonstrated that miR-106b was significantly increased both in RCC tissues and cell lines. Luciferase reporter assays revealed that miR-106b inhibited Capicua expression by targeting its 3ʹ-UTR sequence. And miR-106b promoted cell proliferation, invasion, EMT progression in RCC cellin vitro, as well as promoted the tumor growth of 786-O cells derived xenografts mice. Additionally, loss of Capicua promoted the activation of MAPK signaling pathway.Conclusion: The study suggested that miR-106b regulated RCC progression through MAPK signaling pathway partly by targeting Capicua, which might provide valuable evidence for therapeutic target development of RCC.

Androgen receptor regulates ASS1P3/miR-34a-5p/ASS1 signaling to promote renal cell carcinoma cell growth

Recent studies have demonstrated that the androgen receptor (AR) could play important roles to promote renal cell carcinoma (RCC) cell proliferation, and other studies have also indicated that suppressing the argininosuccinate synthase 1 (ASS1) could promote proliferation of various tumors. The potential of AR promoting cell proliferation in RCC via altering ASS1, however, remains unclear. Here we found that the expression of ASS1 was lower in RCC tissues than in adjacent normal renal tissues, and a lower ASS1 expression was linked to a worse prognosis in RCC patients. Mechanism dissection showed that AR could decrease ASS1 expression to promote RCC cell proliferation via ASS1P3, a pseudogene of ASS1. The results of RIP assay and AGO2 assay revealed that AR could bind ASS1P3 to increase RCC cell proliferation via altering miR-34a-5p function, which could bind to the 3′UTR of ASS1 to suppress its protein expression. ASS1P3 could function as a miRNA decoy for miR-34a-5p to regulate ASS1 in RCC. Preclinical study also supports the in vitro data. Together, these results demonstrated that ASS1P3 could function as a competing endogenous RNA to suppress RCC cell progression, and targeting this newly identified AR-mediated ASS1P3/miR-34a-5p/ASS1 signaling might help in blocking proliferation.

The Nrf2/HO-1 axis can be a prognostic factor in clear cell renal cell carcinoma.

ObjectiveTo study the protein expression level of Nrf2/HO-1 in clear cell renal cell carcinoma (ccRCC) and adjacent normal tissue and to explore its relationship with clinicopathological characteristics and prognosis in ccRCC patients.Materials and methodsIn total, 152 ccRCC patients with available follow-up and clinical data were enrolled, and sample microarrays were prepared for immunohistochemistry studies. The human ccRCC cell lines 786-O, OS-RC-2, A498, and ACHN were cultured for immunofluorescence. The protein concentrations of five ccRCC patients’ tumor and adjacent normal renal tissues were prepared for Western blotting. Chi-squared tests, Fisher’s exact test, Kaplan–Meier analyses, log-rank tests, and Cox regression were performed for statistical analyses.ResultsThe immunoreactivity results showed that the Nrf2 and HO-1 proteins were found in consistent locations in vitro and were expressed both in ccRCC and adjacent normal tissues. The two proteins were localized in the cytoplasm and nucleus of RCC tumor cells and in adjacent normal tissue cells. The expression levels of Nrf2 and HO-1 were significantly higher in ccRCC tissues than in the adjacent normal tissues. The Nrf2 protein level was found to be significantly correlated with the tumor size. Additionally, higher protein expression levels of Nrf2 and HO-1 were also correlated with worse overall survival outcomes and could potentially be used to predict the prognosis of ccRCC patients.ConclusionOur study provides an important theoretical basis for evaluating the clinical prognosis of ccRCC patients, which implies that the Nrf2/HO-1 axis can be a prognostic factor in ccRCC.

Overexpression of COL5A1 promotes tumor progression and metastasis and correlates with poor survival of patients with clear cell renal cell carcinoma.

Background and aimsCOL5A1 has been identified to be involved in metastasis of clear cell renal cell carcinoma (ccRCC) by bioinformatic analysis. This study aimed to investigate COL5A1 expression and its clinical significance in ccRCC. The function of COL5A1 in ccRCC was further investigated.MethodsCOL5A1 expression was examined in 256 ccRCC tissues and paired adjacent normal renal tissues by immunohistochemistry and real-time quantitative PCR. The clinical significance of COL5A1 expression was evaluated. Downregulation of COL5A1 was achieved using siRNA. The effects of COL5A1 silencing on cell proliferation, apoptosis, migration, invasion in vitro, and tumor growth in vivo were investigated.ResultsCOL5A1 expression was upregulated in the majority of the ccRCC tissues at both protein and mRNA levels. COL5A1 expression was significantly correlated with tumor diameter, tumor stage, tumor grade, distant metastasis, recurrence, necrosis, and sarcomatoid (all P<0.05). COL5A1 expression was also significantly associated with overall survival of ccRCC patients (HR 1.876; P=0.027) and recurrence-free survival of localized ccRCC patients (HR 4.751; P<0.001). The accuracy of TNM, University of California Los Angeles Integrated Staging System, and Mayo clinic stage, size, grade, and necrosis prognostic models was improved when COL5A1 expression was added.ConclusionCOL5A1 knockdown significantly inhibited cell proliferation, induced cell apoptosis, inhibited cell migration and invasion in vitro, and inhibited tumor growth in vivo. Therefore, COL5A1 may be a novel prognostic biomarker and a promising therapeutic target for ccRCC.

Novel long noncoding RNA OTUD6B-AS1 indicates poor prognosis and inhibits clear cell renal cell carcinoma proliferation via the Wnt/\u03b2-catenin signaling pathway

BackgroundThe long noncoding RNA (lncRNA) OTUD6B antisense RNA 1 (OTUD6B-AS1) is oriented in an antisense direction to the protein-coding gene OTUD6B on the opposite DNA strand. TCGA database data show that the expression of the lncRNA OTUD6B-AS1 is downregulated and that OTUD6B-AS1 acts as an antioncogene in a variety of tumors. However, the expression and biological functions of the lncRNA OTUD6B-AS1 are still unknown in tumors, including clear cell renal cell carcinoma (ccRCC).MethodsThe expression level of OTUD6B-AS1 was measured in 75 paired human ccRCC tissue and corresponding adjacent normal renal tissue samples. The correlations between the OTUD6B-AS1 expression level and clinicopathological features were evaluated using the chi-square test. The effects of OTUD6B-AS1 on ccRCC cells were determined via MTT assay, clone formation assay, transwell assay, and flow cytometry. Furthermore, the impact of OTUD6B-AS1 overexpression on the activation of the Wnt/β-catenin signaling pathway was investigated. Finally, ACHN cells with OTUD6B-AS1 overexpression were subcutaneously injected into nude mice to evaluate the influence of OTUD6B-AS1 on tumor growth in vivo.ResultsIn this study, we found that the expression of the lncRNA OTUD6B-AS1 was downregulated in ccRCC tissue samples and that patients with low OTUD6B-AS1 expression had shorter overall survival than patients with high OTUD6B-AS1 expression, which showed that the different expression level of OTUD6B-AS1 indirectly correlated with survival of patients. Lentivirus-mediated OTUD6B-AS1 overexpression significantly decreased the proliferation of ccRCC cells and promoted the apoptosis of the cells. Furthermore, OTUD6B-AS1 overexpression partly inhibited cell migration and invasion. The overexpression of OTUD6B-AS1 decreased the activity of the Wnt/β-catenin pathway and suppressed the expression of epithelial-to-mesenchymal transition (EMT)-related proteins (E-cadherin, N-cadherin and Snail) in ccRCC cells. In addition, compared with the parental ACHN cells, OTUD6B-AS1-overexpressing ACHN cells injected into nude mice exhibited decreased tumor growth in vivo.ConclusionsTaken together, our findings present a road map for targeting the newly identified lncRNA OTUD6B-AS1 to suppress ccRCC progression in cell lines, and these results elucidate a novel potential therapeutic target for ccRCC treatment.