TGFBI-promoted Adhesion, Migration and Invasion of Human Renal Cell Carcinoma Depends on Inactivation of von Hippel-Lindau Tumor Suppressor

The Role of the PAX Genes in Renal Cell Carcinoma

Renal cell carcinoma (RCC) is a significant oncological challenge due to its heterogeneous nature and limited treatment options. The PAX developmental gene family encodes nine highly conserved transcription factors that play crucial roles in embryonic development and organogenesis, which have been implicated in the occurrence and development of RCC. This review explores the molecular landscape of RCC, with a specific focus on the role of the PAX gene family in RCC tumorigenesis and disease progression. Of the various RCC subtypes, clear cell renal cell carcinoma (ccRCC) is the most prevalent, characterized by the loss of the von Hippel-Lindau (VHL) tumor suppressor gene. Here, we review the published literature on the expression patterns and functional implications of PAX genes, particularly PAX2 and PAX8, in the three most common RCC subtypes, including ccRCC, papillary RCC (PRCC), and chromophobe RCC (ChRCC). Further, we review the interactions and potential biological mechanisms involving PAX genes and VHL loss in driving the pathogenesis of RCC, including the key signaling pathways mediated by VHL in ccRCC and associated mechanisms implicating PAX. Lastly, concurrent with our update regarding PAX gene research in RCC, we review and comment on the targeting of PAX towards the development of novel RCC therapies.

Apolipoprotein L1 is a tumor suppressor in clear cell renal cell carcinoma metastasis

The 5-year survival rate of kidney cancer drops dramatically from 93% to 15% when it is metastatic. Metastasis constitutes for 30% of kidney cancer cases, in which clear cell renal cell carcinoma (ccRCC) is the most prominent subtype. By sequencing mRNA of ccRCC patient samples, we found that apolipoprotein L1 (APOL1) was highly expressed in tumors compared to their adjacent normal tissues. This gene has been previously identified in a large body of kidney disease research and was reported as a potential prognosis marker in many types of cancers. However, the molecular function of APOL1 in ccRCC, especially in metastasis, remained unknown. In this study, we modulated the expression of APOL1 in various renal cancer cell lines and analyzed their proliferative, migratory, and invasive properties. Strikingly, APOL1 overexpression suppressed ccRCC metastasis both in vitro and in vivo. We then explored the mechanism by which APOL1 alleviated ccRCC malignant progression by investigating its downstream pathways. APOL1 overexpression diminished the activity of focal adhesive molecules, Akt signaling pathways, and EMT processes. Furthermore, in the upstream, we discovered that miR-30a-3p could inhibit APOL1 expression. In conclusion, our study revealed that APOL1 play a role as a tumor suppressor in ccRCC and inhibit metastasis, which may provide novel potential therapeutic approaches for ccRCC patients.

Pick-up single-cell proteomic analysis for quantifying up to 3000 proteins in a Mammalian cell

The shotgun proteomic analysis is currently the most promising single-cell protein sequencing technology, however its identification level of ~1000 proteins per cell is still insufficient for practical applications. Here, we develop a pick-up single-cell proteomic analysis (PiSPA) workflow to achieve a deep identification capable of quantifying up to 3000 protein groups in a mammalian cell using the label-free quantitative method. The PiSPA workflow is specially established for single-cell samples mainly based on a nanoliter-scale microfluidic liquid handling robot, capable of achieving single-cell capture, pretreatment and injection under the pick-up operation strategy. Using this customized workflow with remarkable improvement in protein identification, 2449-3500, 2278-3257 and 1621-2904 protein groups are quantified in single A549 cells (n = 37), HeLa cells (n = 44) and U2OS cells (n = 27) under the DIA (MBR) mode, respectively. Benefiting from the flexible cell picking-up ability, we study HeLa cell migration at the single cell proteome level, demonstrating the potential in practical biological research from single-cell insight.

TGFBI as a candidate biomarker for non-invasive diagnosis of early-stage endometriosis

STUDY QUESTION

Can cartilage oligomeric matrix protein (COMP) and transforming growth factor-β-induced protein ig-h3 (TGFBI) alone or in combination with cancer antigen 125 (CA-125) be considered as potential blood biomarkers of endometriosis?

SUMMARY ANSWER

The results of this study indicate that COMP has no diagnostic value. TGFBI has potential as a non-invasive biomarker of the early stages of endometriosis, while TGFBI together with CA-125 has similar diagnostic characteristics as CA-125 alone for all stages of endometriosis.

WHAT IS KNOWN ALREADY

Endometriosis is a common, chronic gynecological disease that significantly affects patient quality of life by causing pain and infertility. The gold standard for diagnosis is visual inspection of pelvic organs by laparoscopy, therefore there is an urgent need for discovery of non-invasive biomarkers for endometriosis to reduce diagnostic delays and allow earlier treatment of patients. The potential biomarkers for endometriosis evaluated in this study (COMP and TGFBI) were previously identified by our proteomic analysis of peritoneal fluid samples.

STUDY DESIGN, SIZE, DURATION

This is a case-control study divided into a discovery (n = 56 patients) and a validation phase (n = 237 patients). All patients were treated between 2008 and 2019 in a tertiary medical center.

PARTICIPANTS/MATERIALS, SETTING, METHOD

Patients were stratified based on the laparoscopic findings. The discovery phase included 32 endometriosis patients (cases) and 24 patients with confirmed absence of endometriosis (controls). The validation phase included 166 endometriosis and 71 control patients. Concentrations of COMP and TGFBI were measured by ELISA in plasma samples, whereas concentration of CA-125 was measured using a clinically validated assay for serum samples. Statistical and receiver operating characteristic (ROC) curve analyses were performed. The classification models were built using the linear support vector machine (SVM) method with the SVM built-in feature ranking method.

MAIN RESULTS AND THE ROLE OF CHANCE

The discovery phase revealed significantly increased concentration of TGFBI, but not COMP, in plasma samples of patients with endometriosis compared to controls. In this smaller cohort, univariate ROC analysis showed fair diagnostic potential of TGFBI, with an AUC value of 0.77, sensitivity of 58%, and specificity of 84%. The classification model built using linear SVM and combining TGFBI and CA-125 showed an AUC value of 0.91, sensitivity of 88% and specificity of 75% in distinguishing patients with endometriosis from controls. The validation phase results revealed similar diagnostic characteristics of the SVM model combining TGFBI and CA-125, with an AUC value of 0.83, sensitivity of 83% and specificity of 67% and CA-125 alone with AUC value of 0.83, sensitivity of 73% and specificity of 80%. TGFBI exhibited good diagnostic potential for early-stage endometriosis (revised American Society for Reproductive Medicine stage I-II), with an AUC value of 0.74, sensitivity of 61% and specificity of 83% compared to CA-125, which had an AUC value of 0.63, sensitivity of 60% and specificity of 67%. An SVM model combining TGFBI and CA-125 showed a high AUC value of 0.94 and sensitivity of 95% for diagnosing moderate-to-severe endometriosis.

LIMITATIONS, REASONS FOR CAUTION

The diagnostic models were built and validated from a single endometriosis center, and thus further validation and technical verification in a multicenter study with a larger cohort is needed. Additional limitation was lack of histological confirmation of disease for some patients in the validation phase.

WIDER IMPLICATIONS OF THE FINDINGS

This study revealed for the first time increased concentration of TGFBI in plasma samples of patients with endometriosis, particularly those with minimal-to-mild endometriosis, compared to controls. This is the first step in considering TGFBI as a potential non-invasive biomarker for the early stages of endometriosis. It also opens a path for new basic research to investigate the importance of TGFBI in the pathophysiology of endometriosis. Further studies are needed to confirm the diagnostic potential of a model based on TGFBI and CA-125 for the non-invasive diagnosis of endometriosis.

STUDY FUNDING/COMPETING INTEREST(S)

The preparation of this manuscript was supported by grant J3-1755 from the Slovenian Research Agency to T.L.R and EU H2020-MSCA-RISE project TRENDO (grant 101008193). All authors declare that they have no conflicts of interest.

TRIAL REGISTRATION NUMBER

NCT0459154.

Integrative analysis of transcriptomic landscape and urinary signature reveals prognostic biomarkers for clear cell renal cell carcinoma

Background

Clear cell renal cell carcinoma (ccRCC) patients with venous tumor thrombus (VTT) have poor prognosis. We aimed to reveal features of ccRCC with VTT and develop a urine-based prognostic classifier to predict ccRCC prognosis through integrative analyses of transcriptomic landscape and urinary signature.

Methods

RNA sequencing was performed in five patients with ccRCC thrombus-tumor-normal tissue triples, while mass spectrometry was performed for urine samples from 12 ccRCC and 11 healthy controls. A urine-based classifier consisting of three proteins was developed to predict patients' survival and validated in an independent cohort.

Results

Transcriptomic analysis identified 856 invasion-associated differentially expressed genes (DEGs). Furthermore, proteomic analysis showed 133 differentially expressed proteins (DEPs). Integration of transcriptomic landscape and urinary signature reveals 6 urinary detectable proteins (VSIG4, C3, GAL3ST1, TGFBI, AKR1C3, P4HB) displaying abundance changes consistent with corresponding genes in transcriptomic profiling. According to TCGA database, VSIG4, TGFBI, and P4HB were significantly overexpressed in patients with shorter survival and might be independent prognostic factors for ccRCC (all p<0.05). A prognostic classifier consisting of the three DEPs highly associated with survival performed satisfactorily in predicting overall survival (HR=2.0, p<0.01) and disease-free survival (HR=1.6, p<0.001) of ccRCC patients. The ELISA analysis of urine samples from an independent cohort confirmed the satisfied predictive power of the classifier for pathological grade (AUC=0.795, p<0.001) and stage (AUC=0.894, p<0.001).

Conclusion

Based on integrative analyses of transcriptomic landscape and urinary signature, the urine-based prognostic classifier consisting of VSIG4, TGFBI, and P4HB has satisfied predictive power of ccRCC prognosis and may facilitate ccRCC molecular subtyping and treatment.

The Extracellular Matrix Environment of Clear Cell Renal Cell Carcinoma

Simple Summary

The extracellular matrix (ECM) controls fundamental properties of tumors, including growth, blood vessel investment, and invasion. The ECM defines rigidity of tumor tissue and individual ECM proteins have distinct biological effects on tumor cells. This article reviews the composition and biological functions of the ECM of clear cell renal cell carcinoma (ccRCC). The most frequent initiating genetic mutation in ccRCC inactivates the VHL gene, which plays a direct role in organizing the ECM. This is predicted to result in local ECM modification, which promotes the growth of tumor cells and the invasion of blood vessels. Later in tumor growth, connective tissue cells are recruited, which are predicted to produce large amounts of ECM, affecting the growth and invasive behaviors of tumor cells. Strategies to therapeutically control the ECM are under active investigation and a better understanding of the ccRCC ECM will determine the applicability of ECM-modifying drugs to this type of cancer.

Abstract

The extracellular matrix (ECM) of tumors is a complex mix of components characteristic of the tissue of origin. In the majority of clear cell renal cell carcinomas (ccRCCs), the tumor suppressor VHL is inactivated. VHL controls matrix organization and its loss promotes a loosely organized and angiogenic matrix, predicted to be an early step in tumor formation. During tumor evolution, cancer-associated fibroblasts (CAFs) accumulate, and they are predicted to produce abundant ECM. The ccRCC ECM composition qualitatively resembles that of the healthy kidney cortex in which the tumor arises, but there are important differences. One is the quantitative difference between a healthy cortex ECM and a tumor ECM; a tumor ECM contains a higher proportion of interstitial matrix components and a lower proportion of basement membrane components. Another is the breakdown of tissue compartments in the tumor with mixing of ECM components that are physically separated in healthy kidney cortex. Numerous studies reviewed in this work reveal effects of specific ECM components on the growth and invasive behaviors of ccRCCs, and extrapolation from other work suggests an important role for ECM in controlling ccRCC tumor rigidity, which is predicted to be a key determinant of invasive behavior.

Multi-Omics Profiling to Assess Signaling Changes upon VHL Restoration and Identify Putative VHL Substrates in Clear Cell Renal Cell Carcinoma Cell Lines

The inactivation of von Hippel–Lindau (VHL) is critical for clear cell renal cell carcinoma (ccRCC) and VHL syndrome. VHL loss leads to the stabilization of hypoxia-inducible factor α (HIFα) and other substrate proteins, which, together, drive various tumor-promoting pathways. There is inadequate molecular characterization of VHL restoration in VHL-defective ccRCC cells. The identities of HIF-independent VHL substrates remain elusive. We reinstalled VHL expression in 786-O and performed transcriptome, proteome and ubiquitome profiling to assess the molecular impact. The transcriptome and proteome analysis revealed that VHL restoration caused the downregulation of hypoxia signaling, glycolysis, E2F targets, and mTORC1 signaling, and the upregulation of fatty acid metabolism. Proteome and ubiquitome co-analysis, together with the ccRCC CPTAC data, enlisted 57 proteins that were ubiquitinated and downregulated by VHL restoration and upregulated in human ccRCC. Among them, we confirmed the reduction of TGFBI (ubiquitinated at K676) and NFKB2 (ubiquitinated at K72 and K741) by VHL re-expression in 786-O. Immunoprecipitation assay showed the physical interaction between VHL and NFKB2. K72 of NFKB2 affected NFKB2 stability in a VHL-dependent manner. Taken together, our study generates a comprehensive molecular catalog of a VHL-restored 786-O model and provides a list of putative VHL-dependent ubiquitination substrates, including TGFBI and NFKB2, for future investigation.

The role of the extracellular matrix protein TGFBI in cancer

The secreted extracellular protein, transforming growth factor beta induced (TGFBI or βIGH3), has roles in regulating numerous biological functions, including cell adhesion and bone formation, both during embryonic development and during the pathogenesis of human disease. TGFBI has been most studied in the context of hereditary corneal dystrophies, where mutations in TGFBI result in accumulation of TGFBI in the cornea. In cancer, early studies focused on TGFBI as a tumor suppressor, in part by promoting chemotherapy sensitivity. However, in established tumors, TGFBI largely has a role in promoting tumor progression, with elevated levels correlating to poorer clinical outcomes. As an important regulator of cancer progression, TGFBI expression and function is tightly regulated by numerous mechanisms including epigenetic silencing through promoter methylation and microRNAs. Mechanisms to target TGFBI have potential clinical utility in treating advanced cancers, while assessing TGFBI levels could be a biomarker for chemotherapy resistance and tumor progression.

SPARC is a key mediator of TGF-β-induced renal cancer metastasis

Aberrant expression of transforming growth factor-β1 (TGF-β1) is associated with renal cell carcinoma (RCC) progression by inducing cancer metastasis. However, the downstream effector(s) in TGF-β signaling pathway is not fully characterized. In the present study, the elevation of secreted protein acidic and rich in cysteine (SPARC) as a TGF-β regulated gene in RCC was identified by applying differentially expressed gene analysis and microarray analysis, we further confirmed this result in several RCC cell lines. Clinically, the expression of these two genes is positively correlated in RCC patient specimens. Furthermore, elevated SPARC expression is found in all the subtypes of RCC and positively correlated with the RCC stage and grade. In contrast, SPARC expression is inversely correlated with overall and disease-free survival of patients with RCC, suggesting SPARC as a potent prognostic marker of RCC patient survival. Knocking down SPARC significantly inhibits RCC cell invasion and metastasis both in vitro and in vivo. Similarly, in vitro cell invasion can be diminished by using a specific monoclonal antibody. Mechanistically, SPARC activates protein kinase B (AKT) pathway leading to elevated expression of matrix metalloproteinase-2 that can facilitate RCC invasion. Altogether, our data support that SPARC is a critical role of TGF-β signaling network underlying RCC progression and a potential therapeutic target as well as a prognostic marker.

Prognostic Molecular Signatures for Metastatic Potential in Clinically Low-Risk Stage I and II Clear Cell Renal Cell Carcinomas

Introduction: For patients with localized node-negative (Stage I and II) clear cell renal cell carcinomas (ccRCC), current clinicopathological staging has limited predictive capability because of their low risk. Analyzing molecular signatures at the time of nephrectomy can aid in understanding future metastatic potential.

Objective: Develop a molecular signature that can stratify patients who have clinically low risk ccRCC, but have high risk genetic changes driving an aggressive metastatic phenotype.

Patients, Materials, and Methods: Presented is the differential expression of mRNA and miRNA in 44 Stage I and Stage II patients, 21 who developed metastasis within 5 years of nephrectomy, compared to 23 patients who remained disease free for more than 5 years. Extracted RNA from nephrectomy specimens preserved in FFPE blocks was sequenced using RNAseq. MiRNA expression was performed using the TaqMan OpenArray qPCR protocol.

Results: One hundred thirty one genes and 2 miRNA were differentially expressed between the two groups. Canonical correlation (CC) analysis was applied and four CCs (CC32, CC20, CC9, and CC7) have an AUC > 0.65 in our dataset with similar predictive power in the TCGA-KIRC dataset. Gene set enrichment showed CC9 as kidney development/adhesion, CC20 as oxidative phosphorylation pathway, CC32 as RNA binding/spindle and CC7 as immune response. In a multivariate Cox model, the four CCs were able to identify high/low risk groups for metastases in the TCGA-KIRC (p < 0.05) with odds ratios of CC32 = 5.7, CC20 = 4.4, CC9 = 3.6, and CC7 = 2.7.

Conclusion: These results identify molecular signatures for more aggressive tumors in clinically low risk ccRCC patients who have a higher potential of metastasis than would be expected.

A pathogenic variant in the transforming growth factor beta I (TGFBI) in four Iranian extended families segregating granular corneal dystrophy type II: A literature review

OBJECTIVES

Granular and lattice corneal dystrophies (GCDs & LCDs) are autosomal dominant inherited disorders of the cornea. Due to genetic heterogeneity and large genes, unraveling the mutation is challenging.

MATERIALS AND METHODS

Patients underwent comprehensive clinical examination, and targeted next-generation sequencing (NGS) was used for mutation detection. Co-segregation and in silico analysis was accomplished.

RESULTS

Patients suffered from GCD. NGS disclosed a known pathogenic variant, c.371G>A (p.R124H), in exon 4 of TGFBI. The variant co-segregated with the phenotype in the family. Homozygous patients manifested with more severe phenotypes. Variable expressivity was observed among heterozygous patients.

CONCLUSION

The results, in accordance with previous studies, indicate that the c.371G>A in TGFBI is associated with GCD. Some phenotypic variations are related to factors such as modifier genes, reduced penetrance and environmental effects.

TGF-β1 enhanced myocardial differentiation through inhibition of the Wnt/β-catenin pathway with rat BMSCs

OBJECTIVES

To investigate and test the hypotheses that TGF-β1 enhanced myocardial differentiation through Wnt/β-catenin pathway with rat bone marrow mesenchymal stem cells (BMSCs).

MATERIALS AND METHODS

Lentiviral vectors carrying the TGF-β1 gene were transduced into rat BMSCs firstly. Then several kinds of experimental methods were used to elucidate the related mechanisms by which TGF-β1 adjusts myocardial differentiation in rat BMSCs.

RESULTS

Immunocytochemistry revealed that cTnI and Cx43 expressed positively in the cells that were transduced with TGF-β1. The results of Western blot (WB) test showed that the levels of intranuclear β-catenin and total β-catenin were all significantly decreased. However, the cytoplasmic β-catenin level was largely unchanged. Moreover, the levels of GSK-3β were largely unchanged in BMSCs, whereas phosphorylated GSK-3β was significantly decreased in BMSCs. When given the activator of Wnt/β-catenin pathway (lithium chloride, LiCl) to BMSCs transducted with TGF-β1, β-catenin was increased, while phosphorylated β-catenin was decreased. In addition, cyclinD1, MMP-7, and c-Myc protein in BMSCs transducted with Lenti-TGF-β1-GFP were significantly lower.

CONCLUSION

These results indicate that TGF-β1 promotes BMSCs cardiomyogenic differentiation by promoting the phosphorylation of β-catenin and inhibiting cyclinD1, MMP-7, and c-Myc expression in Wnt/β-catenin signaling pathway.

Tumor-associated macrophages promote ovarian cancer cell migration by secreting transforming growth factor beta induced (TGFBI) and tenascin C

A central and unique aspect of high-grade serous ovarian carcinoma (HGSC) is the extensive transcoelomic spreading of tumor cell via the peritoneal fluid or malignant ascites. We and others identified tumor-associated macrophages (TAM) in the ascites as promoters of metastasis-associated processes like extracellular matrix (ECM) remodeling, tumor cell migration, adhesion, and invasion. The precise mechanisms and mediators involved in these functions of TAM are, however, largely unknown. We observed that HGSC migration is promoted by soluble mediators from ascites-derived TAM, which can be emulated by conditioned medium from monocyte-derived macrophages (MDM) differentiated in ascites to TAM-like asc-MDM. A similar effect was observed with IL-10-induced alternatively activated m2c-MDM but not with LPS/IFNγ-induced inflammatory m1-MDM. These observations provided the basis for deconvolution of the complex TAM secretome by performing comparative secretome analysis of matched triplets of different MDM phenotypes with different pro-migratory properties (asc-MDM, m2c-MDM, m1-MDM). Mass spectrometric analysis identified an overlapping set of nine proteins secreted by both asc-MDM and m2c-MDM, but not by m1-MDM. Of these, three proteins, i.e., transforming growth factor beta-induced (TGFBI) protein, tenascin C (TNC), and fibronectin (FN1), have been associated with migration-related functions. Intriguingly, increased ascites concentrations of TGFBI, TNC, and fibronectin were associated with short progression-free survival. Furthermore, transcriptome and secretome analyses point to TAM as major producers of these proteins, further supporting an essential role for TAM in promoting HGSC progression. Consistent with this hypothesis, we were able to demonstrate that the migration-inducing potential of asc-MDM and m2c-MDM secretomes is inhibited, at least partially, by neutralizing antibodies against TGFBI and TNC or siRNA-mediated silencing of TGFBI expression. In conclusion, the present study provides the first experimental evidence that TAM-derived TGFBI and TNC in ascites promote HGSC progression.

TGF-β and microRNA Interplay in Genitourinary Cancers

Genitourinary cancers (GCs) include a large group of different types of tumors localizing to the kidney, bladder, prostate, testis, and penis. Despite highly divergent molecular patterns, most GCs share commonly disturbed signaling pathways that involve the activity of TGF-β (transforming growth factor beta). TGF-β is a pleiotropic cytokine that regulates key cancer-related molecular and cellular processes, including proliferation, migration, invasion, apoptosis, and chemoresistance. The understanding of the mechanisms of TGF-β actions in cancer is hindered by the "TGF-β paradox" in which early stages of cancerogenic process are suppressed by TGF-β while advanced stages are stimulated by its activity. A growing body of evidence suggests that these paradoxical TGF-β actions could result from the interplay with microRNAs: Short, non-coding RNAs that regulate gene expression by binding to target transcripts and inducing mRNA degradation or inhibition of translation. Here, we discuss the current knowledge of TGF-β signaling in GCs. Importantly, TGF-β signaling and microRNA-mediated regulation of gene expression often act in complicated feedback circuits that involve other crucial regulators of cancer progression (e.g., androgen receptor). Furthermore, recently published in vitro and in vivo studies clearly indicate that the interplay between microRNAs and the TGF-β signaling pathway offers new potential treatment options for GC patients.

TGFBI Protein Is Increased in the Urine of Patients with High-Grade Urothelial Carcinomas, and Promotes Cell Proliferation and Migration

Here, we discovered TGFBI as a new urinary biomarker for muscle invasive and high-grade urothelial carcinoma (UC). After biomarker identification using antibody arrays, results were verified in urine samples from a study population consisting of 303 patients with UC, and 128 urological and 58 population controls. The analyses of possible modifying factors (age, sex, smoking status, urinary leukocytes and erythrocytes, and history of UC) were calculated by multiple logistic regression. Additionally, we performed knockdown experiments with TGFBI siRNA in bladder cancer cells and investigated the effects on proliferation and migration by wound closure assays and BrdU cell cycle analysis. TGFBI concentrations in urine are generally increased in patients with UC when compared to urological and population controls (1321.0 versus 701.3 and 475.6 pg/mg creatinine, respectively). However, significantly increased TGFBI was predominantly found in muscle invasive (14,411.7 pg/mg creatinine), high-grade (8190.7 pg/mg) and de novo UC (1856.7 pg/mg; all p < 0.0001). Knockdown experiments in vitro led to a significant decline of cell proliferation and migration. In summary, our results suggest a critical role of TGFBI in UC tumorigenesis and particularly in high-risk UC patients with poor prognosis and an elevated risk of progression on the molecular level.

Interference of the long noncoding RNA CDKN2B-AS1 upregulates miR-181a-5p/TGFβI axis to restrain the metastasis and promote apoptosis and senescence of cervical cancer cells

Long noncoding RNA (lncRNA) CDKN2B-AS1 has been shown to play a crucial role in the development as well as in the prognosis of various human cancers, including cervical cancer. However, the underlying mechanisms need to be further explored between CDKN2B-AS1 and cervical cancer. In the present study, RT-PCR showed that the mRNA level of CDKN2B-AS1 was significantly upregulated while the miR-181a-5p was downregulated in cervical cancer cell lines. In addition, the interference of CDKN2B-AS1 by shRNA resulted in the suppression of cell proliferation, invasion, migration and promotion of apoptosis and senescence, and either CDKN2B-AS1 overexpression or miR-181a-5p showed reversed results. Further studies demonstrated that CDKN2B-AS1 could directly interact with miR-181a-5p, and that there was an inverse correlation between miR-181a-5p and CDKN2B-AS1. In addition, we found that TGFβI was a target of miR-181a-5p and could be downregulated by CDKN2B-AS1 knockdown. Moreover, the in vivo experiments further demonstrated the contribution of CDKN2B-AS1 in cervical cancer including tumor growth, apoptosis inhibition and senescence inhibition, and CDKN2B-AS1 knockdown could inhibit the aforementioned activities. In summary, our study demonstrated that the CDKN2B-AS1/miR-181a-5p/TGFβI axis might play a vital role in cervical cancer development.

SMAD proteins directly suppress PAX2 transcription downstream of transforming growth factor-beta 1 (TGF-β1) signalling in renal cell carcinoma

Canonical TGF-β1 signalling promotes tumor progression by facilitating invasion and metastasis, whereby release of TGF-β1, by (for example) infiltrating immune cells, induces epithelial to mesenchymal transition (EMT). PAX2, a member of the Paired box family of transcriptional regulators, is normally expressed during embryonic development, including in the kidney, where it promotes mesenchymal to epithelial transition (MET). PAX2 expression is silenced in many normal adult tissues. However, in contrast, PAX2 is expressed in several cancer types, including kidney, prostate, breast, and ovarian cancer. While multiple studies have implicated TGF-β superfamily members in modulating expression of Pax genes during embryonic development, few have investigated direct regulation of Pax gene expression by TGF-β1. Here we have investigated direct regulation of PAX2 expression by TGF-β1 in clear cell renal cell carcinoma (CC-RCC) cell lines. Treatment of PAX2-expressing 786-O and A498 CC-RCC cell lines with TGF-β1 resulted in inhibition of endogenous PAX2 mRNA and protein expression, as well as expression from transiently transfected PAX2 promoter constructs; this inhibition was abolished in the presence of expression of the inhibitory SMAD, SMAD7. Using ChIP-PCR we showed TGF-β1 treatment induced SMAD3 protein phosphorylation in 786-O cells, and direct SMAD3 binding to the human PAX2 promoter, which was inhibited by SMAD7 over-expression. Overall, these data suggest that canonical TGF-β signalling suppresses PAX2 transcription in CC-RCC cells due to the direct binding of SMAD proteins to the PAX2 promoter. These studies improve our understanding of tumor progression and epithelial to mesenchyme transition (EMT) in CC-RCC and in other PAX2-expressing cancer types.

Biologic Response of Colorectal Cancer Xenograft Tumors to Sequential Treatment with Panitumumab and Bevacizumab

Recent studies in RAS wild-type (WT) metastatic colorectal cancer (mCRC) suggest that the survival benefits of therapy using anti-epidermal growth factor receptor (anti-EGFR) and anti-vascular endothelial growth factor (anti-VEGF) antibodies combined with chemotherapy are maximized when the anti-EGFR antibody is given as first-line, followed by subsequent anti-VEGF antibody therapy. We report reverse-translational research using LIM1215 xenografts of RAS WT mCRC to elucidate the biologic mechanisms underlying this clinical observation. Sequential administration of panitumumab then bevacizumab (PB) demonstrated a stronger tendency to inhibit tumor growth than bevacizumab then panitumumab (BP). Cell proliferation was reduced significantly with PB (P < .01) but not with BP based on Ki-67 index. Phosphoproteomic analysis demonstrated reduced phosphorylation of EGFR and EPHA2 with PB and BP compared with control. Western blotting showed reduced EPHA2 expression and S897-phosphorylation with PB; RSK phosphorylation was largely unaffected by PB but increased significantly with BP. In quantitative real-time PCR analyses, PB significantly reduced the expression of both lipogenic (FASN, MVD) and hypoxia-related (CA9, TGFBI) genes versus control. These results suggest that numerous mechanisms at the levels of gene expression, protein expression, and protein phosphorylation may explain the improved clinical activity of PB over BP in patients with RAS WT mCRC.

Epirubicin suppresses proliferative and metastatic potential by downregulating transforming growth factor-β-induced expression in urothelial carcinoma

Transforming growth factor‐β‐induced (TGFΒI) is considered to be a vital gene in several carcinomas. In this study we determined the effect of TGFBI on the proliferative and metastatic potential of human urothelial carcinoma (UC) cells as well as its mRNA and protein expression, which were detected by RT‐PCR and western blot, respectively. UC cell proliferation was analyzed by WST‐1 assay and Hoechst 33258 staining. The effect of TGFBI on UC cell metastasis was analyzed using adhesion, migration and invasion assays. We found that TGFBI increased the proliferation of UC cells. Moreover, TGFBI enhanced the adhesion, migration and invasion of UC cells by upregulating MMP‐2, MMP‐9 and calpain‐2 expression. We evaluated the effect of Epirubicin (EPI) on the regulation of TGFBI expression and found that TGFBI acts as a downstream target of EPI and is suppressed by EPI in UC cells. EPI is more effective in inhibiting the proliferation and metastasis of UC cells with high TGFBI expression. This study demonstrates that TGFBI might lead to tumorigenesis and progression of UC and those cells with high TGFBI expression may be vulnerable to relapse. EPI could prove to be a therapeutic option in patients with high TGFBI expressing UC cells.

Transforming growth factor beta induced (TGFBI) is a potential signature gene for mesenchymal subtype high-grade glioma

Previous study revealed that higher expression of transforming growth factor beta induced (TGFBI) is correlated to poorer cancer-specific survival and higher proportion of tumor necrosis and Fuhrman grades III and IV in clear cell renal cell carcinomas. However, the relationships between TGFBI expression and malignant phenotypes of gliomas remain unclear. We downloaded and analyzed data from seven GEO datasets (GSE68848, GSE4290, GSE13041, GSE4271, GSE83300, GSE34824 and GSE84010), the TCGA database and the REMBRANDT database to investigate whether TGFBI could be a biomarker of glioma. From microarray data (GSE68848, GSE4290) and RNA-seq data (TCGA), TGFBI expression levels were observed to correlate positively with pathological grade, and TGFBI expression levels were significantly higher in gliomas than in normal brain tissues. Furthermore, in GSE13041, GSE4271 and the TCGA cohort, TGFBI expression in the mesenchymal (Mes) subtype high-grade glioma (HGG) was significantly higher than that in the proneural subtype. Kaplan-Meier survival analysis of GBM patients in the GSE83300 dataset, REMBRANDT and TCGA cohort revealed that patients in the top 50% TGFBI expression group survived for markedly shorter periods than those in the bottom 50%. Analysis of grade III gliomas showed that the median survival time was significantly shorter in the TGFBI high expression group than in the TGFBI low expression group. In addition, we found that TGFBI expression levels might relate to several classical molecular characterizations of glioma, such as, IDH mutation, TP53 mutation, EGFR amplification, etc. These results suggest that TGFBI expression positively correlates with glioma pathological grades and that TGFBI is a potential signature gene for Mes subtype HGG and a potential prognostic molecule.

Transforming growth factor-β promotes aggressiveness and invasion of clear cell renal cell carcinoma

The molecular mechanisms whereby transforming growth factor-β (TGF-β) promotes clear cell renal cell carcinoma (ccRCC) progression is elusive. The cell membrane bound TGF-β type I receptor (ALK5), was recently found to undergo proteolytic cleavage in aggressive prostate cancer cells, resulting in liberation and subsequent nuclear translocation of its intracellular domain (ICD), suggesting that ALK5-ICD might be a useful cancer biomarker. Herein, the possible correlation between ALK5 full length (ALK5-FL) and ALK5-ICD protein, phosphorylated Smad2/3 (pSmad2/3), and expression of TGF-β target gene PAI-1, was investigated in a clinical ccRCC material, in relation to tumor grade, stage, size and cancer specific survival. Expression of ALK5-FL, ALK5-ICD, pSmad2/3 and PAI-1 protein levels were significantly higher in higher stage and associated with adverse survival. ALK5-ICD, pSmad2/3 and PAI-1 correlated with higher grade, and ALK5-FL, pSmad2/3 and PAI-1 protein levels were significantly correlated with larger tumor size. Moreover, the functional role of the TGF-β - ALK5-ICD pathway were investigated in two ccRCC cell lines by treatment with ADAM/MMP2 inhibitor TAPI-2, which prevented TGF-β-induced ALK5-ICD generation, nuclear translocation, as well as cell invasion. The present study demonstrated that canonical TGF-β Smad2/3 pathway and generation of ALK5-ICD correlates with poor survival and invasion of ccRCC in vitro.

Restoration of type 1 iodothyronine deiodinase expression in renal cancer cells downregulates oncoproteins and affects key metabolic pathways as well as anti-oxidative system

Type 1 iodothyronine deiodinase (DIO1) contributes to deiodination of 3,5,3’,5’-tetraiodo-L-thyronine (thyroxine, T4) yielding of 3,5,3’-triiodothyronine (T3), a powerful regulator of cell differentiation, proliferation, and metabolism. Our previous work showed that loss of DIO1 enhances proliferation and migration of renal cancer cells. However, the global effects of DIO1 expression in various tissues affected by cancer remain unknown. Here, the effects of stable DIO1 re-expression were analyzed on the proteome of renal cancer cells, followed by quantitative real-time PCR validation in two renal cancer-derived cell lines. DIO1-induced changes in intracellular concentrations of thyroid hormones were quantified by L-MS/MS and correlations between expression of DIO1 and potential target genes were determined in tissue samples from renal cancer patients. Stable re-expression of DIO1, resulted in 26 downregulated proteins while 59 proteins were overexpressed in renal cancer cells. The ‘downregulated’ group consisted mainly of oncoproteins (e.g. STAT3, ANPEP, TGFBI, TGM2) that promote proliferation, migration and invasion. Furthermore, DIO1 re-expression enhanced concentrations of two subunits of thyroid hormone transporter (SLC7A5, SLC3A2), enzymes of key pathways of cellular energy metabolism (e.g. TKT, NAMPT, IDH2), sex steroid metabolism and anti-oxidative response (AKR1C2, AKR1B10). DIO1 expression resulted in elevated intracellular concentration of T4. Expression of DIO1-affected genes strongly correlated with DIO1 transcript levels in tissue samples from renal cancer patients as well as with their poor survival. This first study addressing effects of deiodinase re-expression on proteome of cancer cells demonstrates that induced DIO1 re-expression in renal cancer robustly downregulates oncoproteins, affects key metabolic pathways, and triggers proteins involved in anti-oxidative protection. This data supports the notion that suppressed DIO1 expression and changes in local availability of thyroid hormones might favor a shift from a differentiated to a more proliferation-prone state of cancer tissues and cell lines.

The pVHL172 isoform is not a tumor suppressor and up-regulates a subset of pro-tumorigenic genes including TGFB1 and MMP13

The von Hippel-Lindau (VHL) tumor suppressor gene is often deleted or mutated in ccRCC (clear cell renal cell carcinoma) producing a non-functional protein. The gene encodes two mRNA, and three protein isoforms (pVHL₂₁₃, pVHL₁₆₀ and pVHL₁₇₂). The pVHL protein is part of an E3 ligase complex involved in the ubiquitination and proteasomal degradation of different proteins, particularly hypoxia inducible factors (HIF) that drive the transcription of genes involved in the regulation of cell proliferation, angiogenesis or extracellular matrix remodelling. Other non-canonical (HIF-independent) pVHL functions have been described. A recent work reported the expression of the uncharacterized protein isoform pVHL₁₇₂ which is translated from the variant 2 by alternative splicing of the exon 2. This splice variant is sometimes enriched in the ccRCCs and the protein has been identified in the respective samples of ccRCCs and different renal cell lines. Functional studies on pVHL have only concerned the pVHL₂₁₃ and pVHL₁₆₀ isoforms, but no function was assigned to pVHL₁₇₂. Here we show that pVHL₁₇₂ stable expression in renal cancer cells does not regulate the level of HIF, exacerbates tumorigenicity when 786-O-pVHL₁₇₂ cells were xenografted in mice. The pVHL₁₇₂-induced tumors developed a sarcomatoid phenotype. Moreover, pVHL₁₇₂ expression was shown to up regulate a subset of pro-tumorigenic genes including TGFB1, MMP1 and MMP13. In summary we identified that pVHL₁₇₂ is not a tumor suppressor. Furthermore our findings suggest an antagonistic function of this pVHL isoform in the HIF-independent aggressiveness of renal tumors compared to pVHL₂₁₃.

AHNAK2 is a Novel Prognostic Marker and Oncogenic Protein for Clear Cell Renal Cell Carcinoma

Integrative database analysis was performed to identify novel candidate oncogene AHNAK2 overexpressed in clear cell renal cell carcinoma (ccRCC). However, the function of AHNAK2 in cancer cells is currently unknown. In this study, we first confirmed the upregulation of AHNAK2 in ccRCC tissues compared with adjacent normal tissues in 15 pairs of samples. Then we analyzed AHNAK2 expression in a large cohort of ccRCC patient samples (n = 355), and found that up-regulation of AHNAK2 was positively correlated with tumor progression and poor survival (p = 0.032). Knockdown of AHNAK2 inhibited cancer cell proliferation, colony formation and migration in vitro and tumorigenic ability in vivo. Meanwhile, knockdown of AHNAK2 impaired the cell oncologic-metabolism by inhibiting lipid synthesis. Moreover, we observed that expression of AHNAK2 was greatly upregulated, at least in part, by hypoxia in cancer cells. By using chromatin immune-precipitation (CHIP) and promoter-luciferase reporter assays, we identified that upregulation of AHNAK2 induced by hypoxia was hypoxia-inducible factor-1α (HIF1α)-dependent. Knockdown of AHNAK2 impaired hypoxia-induced epithelial-mesenchymal transition (EMT) and stem cell-like properties. Considered together, we reveal that AHNAK2 is upregulated in cancer cells and hypoxic upregulation of AHNAK2 can drive tumorigenesis and progression by supporting EMT and cancer cell stemness. Thus, AHNAK2 is a novel prognostic marker and an oncogenic protein for ccRCC.

Induction of type 1 iodothyronine deiodinase expression inhibits proliferation and migration of renal cancer cells

Type 1 iodothyronine deiodinase (DIO1) regulates peripheral metabolism of thyroid hormones that control cellular proliferation, differentiation and metabolism. The significance of DIO1 in cancer is unknown. In this study we hypothesized that diminished expression of DIO1, observed in renal cancer, contributes to the carcinogenic process in the kidney. Here, we demonstrate that ectopic expression of DIO1 in renal cancer cells changes the expression of genes controlling cell cycle, including cyclin E1 and E2F5, and results in inhibition of proliferation. The expression of genes encoding collagens (COL1A1, COL4A2, COL5A1), integrins (ITGA4, ITGA5, ITGB3) and transforming growth factor-β-induced (TGFBI) is significantly altered in renal cancer cells with induced expression of DIO1. Finally, we show that overexpression of DIO1 inhibits migration of renal cancer cells. In conclusion, we demonstrate for the first time that loss of DIO1 contributes to renal carcinogenesis and that its induced expression protects cells against cancerous proliferation and migration.

Identification of two novel mutations in the cornea-specific TGFBI gene causing unique phenotypes in patients with corneal dystrophies

The purpose of this study was to report on two novel missense mutations of the cornea-specific TGFBI gene in one single patient and in two generations of a family diagnosed with unique corneal dystrophy (CD) phenotypes. Ophthalmologic examination, in several cases ocular coherence tomography of the anterior segment (AS-OCT), was performed in 21 affected patients and in two unaffected members of one affected family. Coding regions of the TGFBI gene were direct sequenced in all 23 individuals. The two novel mutations were verified by RFLP analysis. A novel mutation c.1640T > G (p.Phe574Cys) in exon 12 of the TGFBI gene was detected in one single patient with recurrent granular intrastromal deposits comparable to a type of granular dystrophy. In AS-OCT, the deposit pattern reached up to the Descemet's layer. A further novel mutation c.393G > T(p.Glu131Asp) in exon 4 of the TGFBI gene was detected in all three affected members of one family with superficial cloud- and honeycomb-like opacifications, comparable to a Schnyder corneal dystrophy. Two unaffected members did not carry this alteration. The two identified novel mutations add other two phenotypes in patients suffering from TGFBI-linked CD to those reported so far. In one case, clinical finding indicates a Schnyder corneal dystrophy-like phenotype due to its superficial crystalline shape, and in the second one, granular deposits who reach Descemet's layer indicate a granular CD subtype. Molecular genetic analysis may help to distinguish those subtypes and to decide for specific treatment in time of a wide variation of corneal surgical techniques.

TGFβ3-mediated induction of Periostin facilitates head and neck cancer growth and is associated with metastasis

The matrix-specific protein periostin (POSTN) is up-regulated in human cancers and associated with cancer growth, metastasis and angiogenesis. Although the stroma of cancer tissues is the main source of POSTN, it is still unclear how POSTN plays a role to facilitate the interplay between cancer cells and cancer-associated fibroblasts (CAFs) in head and neck cancer (HNC), thereby promoting tumorigenesis via modifying the tumor microenvironment. Herein, we have performed studies to investigate POSTN and its role in HNC microenvironment. Our results indicated that POSTN was significantly up-regulated in HNCs, especially in the tissues with lymph node metastasis. Moreover, POSTN was highly enriched in the stroma of cancer tissues and produced mainly by CAFs. More importantly, we have pinpointed TGF-β3 as the major upstream molecular that triggers the induction of POSTN in CAFs. As such, during the interaction between fibroblasts and cancer cells, the increased stromal POSTN induced by TGF-β3 directly accelerated the growth, migration and invasion of cancer cells. Hence, our study has provided a novel modulative role for POSTN on HNC progression and further reveals POSTN as an effective biomarker to predict metastasis as well as a potential cancer therapeutic target.

Ganglioside, disialosyl globopentaosylceramide (DSGb5), enhances the migration of renal cell carcinoma cells

About one third of renal cell carcinoma (RCC) patients exhibit metastasis upon initial presentation. However, the molecular basis for RCC metastasis is not fully understood. A ganglioside, disialosyl globopentaosylceramide (DSGb5), was originally isolated from RCC tissue extracts, and its expression is correlated with RCC metastatic potential. DSGb5 is synthesized by GalNAc α2,6-sialyltransferase VI (ST6GalNAcVI) and is expressed on the surface of RCC cells. Importantly, DSGb5 binds to sialic acid-binding Ig-like lectin-7 (Siglec-7) expressed on natural killer (NK) cells, thereby inhibiting NK-cell cytotoxicity. However, the role of DSGb5 in RCC progression remains obscure. To address this issue, we used ACHN cells derived from malignant pleural effusion of a patient with metastatic RCC. Using the limiting dilution method, we isolated three independent clones with different DSGb5 expression levels. Comparison of these clones indicated that the cloned cells with high DSGb5 expression levels exhibited greater migration potential, compared to the clone with low DSGb5 expression levels. In contrast, DSGb5 expression levels exerted no significant effect on cell proliferation. We then established the ACHN-derived cell lines that stably expressed siRNA against ST6GalNAcVI mRNA or control siRNA. Importantly, the ST6GalNAcVI-knockdown cells expressed low levels of DSGb5. We thus demonstrated the significantly decreased migration potential of the ST6GalNAcVI-knockdown cells with low DSGb5 expression levels, compared to the control siRNA-transfected cells expressing high DSGb5 levels, but no significant difference in the cell proliferation. Thus, DSGb5 expression may ensure the migration of RCC cells. We propose that DSGb5 expressed on RCC cells may determine their metastatic capability.

Expression of Genes Involved in Cellular Adhesion and Extracellular Matrix Remodeling Correlates with Poor Survival of Patients with Renal Cancer

PURPOSE

Renal cell carcinoma is the most common highly metastatic kidney malignancy. Adhesion has a crucial role in the metastatic process. TGF (transforming growth factor)-β1 is a pleiotropic cytokine that influences cancerous transformation. We hypothesized that 1) changes in the expression of adhesion related genes may influence survival rate of patients with renal cell carcinoma and 2) TGF-β1 may contribute to changed expression of adhesion related genes.

MATERIALS AND METHODS

Two-step quantitative real-time polymerase chain reaction arrays were used to analyze the expression of adhesion related genes in 77 tumors and matched pair controls. The prognostic significance of genes was evaluated in TCGA (The Cancer Genome Atlas) data on 468 patients with renal cell carcinoma. Quantitative real-time polymerase chain reaction and Western blot were applied for TGF-β1 analysis. TGF-β1 mediated regulation of gene expression was analyzed by TGF-β1 supplementation of Caki-2 cells and quantitative real-time polymerase chain reaction.

RESULTS

The expression of 19 genes related to adhesion and extracellular matrix remodeling was statistically significantly disturbed in renal cell carcinoma compared with controls. The 10-gene expression signature (COL1A1, COL5A1, COL11A1, FN1, ICAM1, ITGAL, ITGAM, ITGB2, THBS2 and TIMP1) correlated with poor survival (HR 2.85, p = 5.7e-10). TGF-β1 expression was 22 times higher in renal cell carcinoma than in controls (p <0.0001). TGF-β1 induced expression of TGFBI, COL1A1, COL5A1, COL8A1, FN1, ITGA5, ITGAM and TIMP1 in a renal cell carcinoma derived cell line.

CONCLUSIONS

Disturbed expression of genes involved in adhesion and extracellular matrix remodeling develops early during renal cell carcinoma carcinogenesis and correlates with poor survival. TGF-β1 contributes to changed expression of extracellular matrix and adhesion related genes. Bioinformatic analysis performed on a broad panel of cancers of nonkidney origin suggests that disturbed expression of genes related to extracellular matrix and adhesion may be a universal feature of cancerous progression.

Myt3 Mediates Laminin-V/Integrin-β1-Induced Islet-Cell Migration via Tgfbi

Myt3 is a prosurvival factor in pancreatic islets; however, its role in islet-cell development is not known. Here, we demonstrate that myelin transcription factor 3 (Myt3) is expressed in migrating islet cells in the developing and neonatal pancreas and thus sought to determine whether Myt3 plays a role in this process. Using an ex vivo model of islet-cell migration, we demonstrate that Myt3 suppression significantly inhibits laminin-V/integrin-β1-dependent α- and β-cell migration onto 804G, and impaired 804G-induced F-actin and E-cadherin redistribution. Exposure of islets to proinflammatory cytokines, which suppress Myt3 expression, had a similar effect, whereas Myt3 overexpression partially rescued the migratory ability of the islet cells. We show that loss of islet-cell migration, due to Myt3 suppression or cytokine exposure, is independent of effects on islet-cell survival or proliferation. Myt3 suppression also had no effect on glucose-induced calcium influx, F-actin remodeling or insulin secretion by β-cells. RNA-sequencing (RNA-seq) analysis of transduced islets showed that Myt3 suppression results in the up-regulation of Tgfbi, a secreted diabetogenic factor thought to impair cellular adhesion. Exposure of islets to exogenous transforming growth factor β-induced (Tgfbi) impaired islet-cell migration similar to Myt3 suppression. Taken together, these data suggest a model by which cytokine-induced Myt3 suppression leads to Tgfbi de-repression and subsequently to impaired islet-cell migration, revealing a novel role for Myt3 in regulating islet-cell migration.

Decreased expression of protein tyrosine phosphatase non-receptor type 12 is involved in the proliferation and recurrence of bladder transitional cell carcinoma

Protein tyrosine phosphatase non-receptor type 12 (PTPN12) has been shown to be involved in the development of a number of types of carcinoma. However, the effect of PTPN12 on the proliferation and recurrence of human bladder transitional cell carcinoma (TCC) is unclear. The present study aimed to investigate the expression and function of PTPN12 in human TCC. Samples from 164 patients with TCC, in addition to 146 patients undergoing bladder surgery for indications other than TCC, were examined. PTPN12 protein expression was examined using immunohistochemistry and western blotting, and PTPN12 mRNA expression was examined using reverse transcription-quantitative polymerase chain reaction. PTPN12 expression was increased following transfection with the PTPN12-expressing, pcDEF3 vector, and PTPN12 expression was decreased by RNA interference, in four TCC cell lines. The proliferation of TCC cells was analyzed by a WST-1 assay and in xenografts on BALB/C nude mice. The effect of PTPN12 on tumor recurrence was analyzed by adhesion, migration and invasion assays in TCC cell lines. PTPN12 expression was significantly decreased in TCC tissues compared with that in normal urothelium, and the level of PTPN12 expression was negatively correlated with tumor size, pathological grade, clinical stage and tumor recurrence. Furthermore, decreased expression of PTPN12 significantly enhanced the proliferation of TCC cells in vitro and in vivo. TCC cells with lower levels of PTPN12 exhibited greater adhesion, migration and invasion. In conclusion, PTPN12 expression is downregulated in human TCC. Restoring PTPN12 activity may represent a novel therapeutic strategy for this disease.

Fighting against kidney diseases with small interfering RNA: opportunities and challenges

The significant improvements in siRNA therapy have been achieved, which have great potential applications in humans. The kidney is a comparatively easy target organ of siRNA therapy due to its unique structural and functional characteristics. Here, we reviewed recent achievements in siRNA design, delivery and application with focuses on kidney diseases, in particular kidney transplant-related injuries. In addition, the strategy for increasing serum stability and immune tolerance of siRNA was also discussed. At last, the future challenges of siRNA therapy including organ/tissue/cell-specific delivery and time-controlled silence, as well as selecting therapeutic targets, were addressed as well.

TGF-beta induced RBL2 expression in renal cancer cells by down-regulating miR-93

PURPOSE

TGF-beta can induce G1 arrest via many mechanisms including up-regulating p21, p27, and Rb. However, as the member of Rb family, whether RBL2 is induced by TGF-beta treatment remains exclusive.

METHODS

The expression of RBL2 and miR-93 after TGF-beta treatment was determined by quantitative real-time PCR and western blot. The growth of renal cancer cells was determined by CCK-8 assays and cell cycle was determined by PI staining. The binding of miR-93 on RBL2 3'-UTR was determined by double luciferase system.

RESULTS

In renal cancer cells, TGF-beta treatment induced expression of RBL2 in a time- and concentration-dependent manner, and RBL2 mediated TGF-beta induced growth inhibition and cell cycle arrest in renal cancer cells. Furthermore, we found that miR-93 directly targeted RBL2 by binding to its 3'-UTR in renal cancer cells. Over-expression of miR-93 significantly reduced the expression of RBL2, whereas knock down of miR-93 up-regulated the expression of RBL2. More importantly, TGF-beta treatment inhibited miR-93 expression, which resulted in up-regulation of RBL2 after TGF-beta treatment.

CONCLUSION

TGF-beta induced RBL2 expression through down-regulating miR-93 in renal cancer cells. The newly identified TGF-beta/miR-93/RBL2 signal pathway reveals a new mechanism of TGF-beta induced growth arrest in renal cancer.

lncRNA H19/miR-675 axis represses prostate cancer metastasis by targeting TGFBI

Prostate cancer is a leading cause of cancer-related mortality in men worldwide and there is a lack of effective treatment options for advanced (metastatic) prostate cancer. Currently, limited knowledge is available concerning the role of long non-coding RNAs in prostate cancer metastasis. In this study, we found that long non-coding RNA H19 (H19) and H19-derived microRNA-675 (miR-675) were significantly downregulated in the metastatic prostate cancer cell line M12 compared with the non-metastatic prostate epithelial cell line P69. Upregulation of H19 in P69 and PC3 cells significantly increased the level of miR-675 and repressed cell migration; however, ectopic expression of H19 in M12 cells could not increase the level of miR-675 and therefore had no effect on cell migration. Furthermore, we found that the expression level of either H19 or miR-675 in P69 cells was negatively associated with the expression of transforming growth factor β induced protein (TGFBI), an extracellular matrix protein involved in cancer metastasis. Dual luciferase reporter assays showed that miR-675 directly bound with 3'UTR of TGFBI mRNA to repress its translation. Taken together, we show for the first time that the H19-miR-675 axis acts as a suppressor of prostate cancer metastasis, which may have possible diagnostic and therapeutic potential for advanced prostate cancer.

Identification and validation of TGFBI as a promising prognosis marker of clear cell renal cell carcinoma

OBJECTIVE

To identify prognostic biomarkers in clear cell renal cell carcinoma (ccRCC) using a proteomic approach.

MATERIAL AND METHODS

We performed a comparative proteomic profiling of ccRCC and normal renal tissues from 9 different human specimens. We assessed differential protein expression by iTRAQ (isobaric tagging reagent for absolute quantify) labeling with regard to tumor aggressiveness according to the stage, size, grade, and necrosis (SSIGN) score and confirmed our results using Western blot (9 patients) and immunohistochemistry (135 patients) analysis.

RESULTS

After proteomic analysis, 928 constitutive proteins were identified. Among these proteins, 346 had a modified expression in tumor compared with that of normal tissue. Pathway and integrated analyses indicated the presence of an up-regulation of the pentose phosphate pathway in aggressive tumors. In total, 14 proteins were excreted and could potentially become biomarkers. Overexpression of transforming growth factor, beta-induced (TGFBI) in ccRCC was confirmed using Western blot and immunohistochemistry analysis. A significant association was found between the presence of TGFBI expression with tumor category T3-4 (P<0.0001), Fuhrman grades III and IV (P<0.0001), tumor size>4cm (P<0.0001), presence of tumor necrosis (P<0.0001), nodal involvement (n = 0.009), metastasis (P = 0.012), SSIGN score≥5 (P<0.0001), cancer progression (P<0.0001), and cancer-specific death (P<0.0001). Cancer-specific survival was significantly better for patients with no cytoplasmic TGFBI expression (1-, 3-, 5-y cancer-specific survival of 94.7%, 87.8%, and 73.4% vs. 92.9%, 71.2%, and 49.8%, respectively; P<0.0001).

CONCLUSION

We identified 346 proteins involved in renal carcinogenesis and confirmed the presence of a metabolic shift in aggressive tumors. TGFBI was overexpressed in tumors with high SSIGN scores and was significantly associated with oncologic outcomes.

Overexpression of flotillin-1 is involved in proliferation and recurrence of bladder transitional cell carcinoma

Flotillin-1 (FLOT1) is known to have a role in tumorigenesis; however, the effect of FLOT1 on proliferation and recurrence of human transitional cell carcinoma (TCC) is unclear. Samples from 156 TCC patients and 142 patients undergoing open bladder surgery for indications other than TCC were used in the present study. FLOT1 protein expression was determined by immunohistochemistry and western blot analysis, and mRNA expression was detected by RT-PCR and real-time PCR. A FLOT1-expressing pcDEF3 vector was stably transfected into 4 TCC cell lines and FLOT1 expression was decreased by RNAi. Proliferative analysis of TCC cells was detected by the WST-1 assay and a xenograft model using BALB/C nude mice. The association between FLOT1 expression and TCC recurrence was also analyzed by adhesion, migration and invasion assays. FLOT1 expression in TCC was significantly overexpressed compared to normal urothelial tissue, and the level of FLOT1 expression was significantly correlated with tumor size, pathologic grade, clinical stage and recurrence. In addition, FLOT1 significantly increased the proliferative ability of TCC cells in vitro and in vivo. TCC cells with a high level of FLOT1 expression exhibited a higher level of adhesion, migration and invasion. FLOT1 expression was shown to be upregulated in human TCC. These findings suggest that FLOT1 plays an important role in the proliferation and recurrence of TCC and that silencing FLOT1 expression might be a novel therapeutic strategy.

Stage-dependent prognostic impact of molecular signatures in clear cell renal cell carcinoma

Purpose

To enhance prognostic information of protein biomarkers for clear cell renal cell carcinomas (ccRCCs), we analyzed them within prognostic groups of ccRCC harboring different tumor characteristics of this clinically and molecularly heterogeneous tumor entity.

Methods

Tissue microarrays from 145 patients with primary ccRCC were immunohistochemically analyzed for VHL (von Hippel-Lindau tumor suppressor), Ki67 (marker of proliferation 1), p53 (tumor protein p53), p21 (cyclin-dependent kinase inhibitor 1A), survivin (baculoviral IAP repeat containing 5), and UEA-1 (Ulex europaeus agglutinin I) to assess microvessel-density.

Results

When analyzing all patients, nuclear staining of Ki67 (hazard ratio [HR] 1.08, 95% confidence interval [CI] 1.04–1.12) and nuclear survivin (nS; HR 1.04, 95% CI 1.01–1.08) were significantly associated with disease-specific survival (DSS). In the cohort of patients with advanced localized or metastasized ccRCC, high staining of Ki67, p53 and nS predicted shorter DSS (Ki67: HR 1.07, 95% CI 1.02–1.11; p53: HR 1.05, 95% CI 1.01–1.09; nS: HR 1.08, 95% CI 1.02–1.14). In organ-confined ccRCC, patients with high p21-staining had a longer DSS (HR 0.96, 95% CI 0.92–0.99). In a multivariate model with stepwise backward elimination, tumor size and p21-staining showed a significant association with DSS in patients with “organ-confined” ccRCCs. The p21-staining increased the concordance index of tumor size from 0.75 to 0.78. In patients with “organ-confined” ccRCC, no disease-related deaths occurred in the group with p21-expression below the threshold of 32.5% p21-positive cells (log rank test: P=0.002).

Conclusion

The prognostic information of the studied protein biomarkers depended on anatomic tumor stages, which displayed different acquired biological tumor characteristics. Analysis of prognostic factors within different clinical ccRCC groups could help to enhance their prognostic power. The p21-staining was an independent prognostic factor and increased prognostic accuracy in a predictive model in “organ-confined” ccRCC.

Anticancer effect of salidroside on A549 lung cancer cells through inhibition of oxidative stress and phospho-p38 expression

Oxidative stress is important in carcinogenesis and metastasis. Salidroside, a phenylpropanoid glycoside isolated from Rhodiola rosea L., shows potent antioxidant properties. The aim of the present study was to investigate the roles of salidroside in cell proliferation, the cell cycle, apoptosis, invasion and epithelial-mesenchymal transition (EMT) in A549 cells. The human alveolar adenocarcinoma cell line, A549, was incubated with various concentrations of salidroside (0, 1, 5, 10 and 20 μg/ml) and cell proliferation was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Propidium iodide (PI) staining was used to determine the cell cycle by flow cytometry. Cell apoptosis was detected by Annexin V-fluorescein isothiocyanate and PI double-staining, and tumor invasion was detected by Boyden chamber invasion assay. Western blot analysis was performed to detect the expression of EMT markers, Snail and phospho-p38. The results showed that salidroside significantly reduced the proliferation of A549 cells, inhibited cell cycle arrest in the G0/G1 phase and induced apoptosis. Salidroside inhibited transforming growth factor-β-induced tumor invasion and suppressed the protein expression of Snail. As an antioxidant, salidroside inhibited the intracellular reactive oxygen species (ROS) formation in a dose-dependent manner in A549 cells, and depletion of intracellular ROS by vitamin C suppressed apoptosis by salidroside treatment. Salidroside was also found to inhibit the expression of phospho-p38 in A549 cells. In conclusion, salidroside inhibits cell proliferation, the cell cycle and metastasis and induces apoptosis, which may be due to its interference in the intracellular ROS generation, thereby, downregulating the ROS-phospho-p38 signaling pathway.

Transforming growth factor beta 1 induces CXCL16 and leukemia inhibitory factor expression in osteoclasts to modulate migration of osteoblast progenitors

The processes of bone resorption and bone formation are tightly coupled in young adults, which is crucial to maintenance of bone integrity. We have documented that osteoclasts secrete chemotactic agents to recruit osteoblast lineage cells, contributing to coupling. Bone formation subsequent to bone resorption becomes uncoupled with aging, resulting in significant bone loss. During bone resorption, osteoclasts release and activate transforming growth factor beta 1 (TGF-β1) from the bone matrix; thus, elevated bone resorption increases the level of active TGF-β in the local environment during aging. In this study, we examined the influences of TGF-β1 on the ability of osteoclasts to recruit osteoblasts. TGF-β1 increased osteoclast expression of the chemokine CXCL16 to promote osteoblast migration. TGF-β1 also directly stimulated osteoblast migration; however, this direct response was blocked by conditioned medium from TGF-β1-treated osteoclasts due to the presence of leukemia inhibitory factor (LIF) in the medium. CXCL16 and LIF expression was dependent on TGF-β1 activation of Smad2 and Smad3. These results establish that TGF-β1 induces CXCL16 and LIF production in osteoclasts, which modulate recruitment of osteoblasts to restore the bone lost during the resorptive phase of bone turnover.

Protein tyrosine phosphatase ζ enhances proliferation by increasing β-catenin nuclear expression in VHL-inactive human renal cell carcinoma cells

OBJECTIVE

We investigated the role of protein tyrosine phosphatase ζ (Ptprz1) in human renal cell carcinoma (RCC) cells' proliferation and associations between Ptprz1 expression and von Hippel-Lindau (VHL) activation.

METHODS

A normal human renal cell line and four human RCC cell lines were used in this study. VHL or Ptprz1 expression in RCC cells was increased by transfection with a VHL or Ptprz1 vector. VHL or Ptprz1 expression was decreased in these cells by siRNA using Lipofectamine 2000. Cells' proliferative activity was assessed by WST-1 assay.

RESULTS

Our results suggested that Ptprz1 was a target of VHL, and a loss of VHL activation increased Ptprz1 expression in RCC cells. Ptprz1 enhanced β-catenin protein expressions in the nuclear fractions of RCC cells and participated in regulating proliferation by activating β-catenin and its downstream genes. In addition, a loss of VHL activity may enhance the proliferative activity of RCC cells by increasing Ptprz1 expression.

CONCLUSION

Ptprz1-enhanced RCC cells' proliferation depends on VHL inactivation, and the Ptprz1/β-catenin pathway may be a potential target for treating RCC with inactive VHL.

The impact of TGF-β1 on the mRNA expression of TβR I, TβR II, Smad4 and the invasiveness of the JEG-3 placental choriocarcinoma cell line

Human choriocarcinoma is one of the most aggressive malignant tumors characterized by early hematogenous spread to lung and brain tissues, and may be a cause of death in patients. Choriocarcinoma may occur following pregnancy and during implantation; however, trophoblastic invasion in human pregnancy is tightly regulated. The transforming growth factor-beta 1 (TGF-β1) has been suggested to play a role in controlling this process. In this study, we investigated the impact of TGF-β1 on invasion, as well as its sites of action in the TGF-β1/Smad pathway using a JEG-3 choriocarcinoma cell line. Following the treatment of cells with different doses of TGF-β1, cell invasion was observed. We also detected the expression of TGF-β receptor type I (TβR I) and TGF-β receptor type II (TβR II), Smad4, matrix metalloprotease (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 in JEG-3 cells. Our data demonstrated that TGF-β1 promoted the invasive capability of JEG-3 cells depending on the downregulation of TβR I, TβR II, Smad4 and the upregulation of MMP-9 and TIMP-1. These observations suggest that TGF-β1 may play a critical role in the initiation of the trophoblastic invasion process.

Gene expression profiling of the synergy of 5-aza-2'-deoxycytidine and paclitaxel against renal cell carcinoma

Background

Renal cell carcinoma (RCC) is one of the most common kidney cancers and is highly resistant to chemotherapy. We previously demonstrated that 5-aza-2^′-deoxycytidine (DAC) could significantly increase the susceptibility of renal cell carcinoma (RCC) cells to paclitaxel (PTX) treatment in vitro, and showed the synergy of DAC and PTX against RCC. The purpose of this study is to investigated the gene transcriptional alteration and investigate possible molecular mechanism and pathways implicated in the synergy of DAC and PTX against RCC.

Methods

cDNA microarray was performed and coupled with real-time PCR to identify critical genes in the synergistic mechanism of both agents against RCC cells. Various patterns of gene expression were observed by cluster analysis. IPA software was used to analyze possible biological pathways and to explore the inter-relationships between interesting network genes.

Results

We found that lymphoid enhancer-binding factor 1 (LEF1), transforming growth factor β-induced (TGFBI), C-X-C motif ligand 5 (CXCL5) and myelocytomatosis viral related oncogene (c-myc) may play a pivotal role in the synergy of DAC and PTX. The PI3K/Akt pathway and other pathways associated with cyclins, DNA replication and cell cycle/mitotic regulation were also associated with the synergy of DAC and PTX against RCC.

Conclusion

The activation of PI3K/Akt-LEF1/β-catenin pathway could be suppressed synergistically by two agents and that PI3K/Akt-LEF1/β-catenin pathway is participated in the synergy of two agents.