Lack of ephrin receptor A1 is a favorable independent prognostic factor in clear cell renal cell carcinoma

Immunohistochemical expression of ephrin receptors in neuroendocrine neoplasms: a case-series of gastroenteropancreatic neuroendocrine neoplasms and a systematic review of the literature

PURPOSE

Erythropoietin-producing hepatocellular (EPH) receptors are the largest known family of tyrosine kinases receptors (TKR) in humans, implicated in cell proliferation, adhesion, migration, tumor angiogenesis, invasion and metastasis. The aim of the present study is to assess the expression of EPHs in neuroendocrine neoplasms (NENs).

METHODS

Immunohistochemical staining of specimens of 30 patients with gastroenteropancreatic and lung NENs was performed for EPH-A1, EPH-A2, EPH-A4, EPH-A5 protein expression, in addition to ki-67 multiplication index and programmed death-ligand 1. Additionally, we performed a systematic review of the available literature in three different databases reporting on the expression of EPH in all neuroendocrine neoplasms.

RESULTS

Positive expression was seen in 16/19 (84%) specimens for EPH-A1, 15/23 (65%) for EPH-A2, 21/24 (88%) for EPH-A4, 24/26 (92%) for EPH-A5. EPH-A1 was expressed in 9/9 pancreatic, 3/4 small intestine, but not in one lung NEN, EPH-A2 in 5/10 pancreatic, 3/4 small intestine and lung, and in one of each of gastric, appendix, colorectal, and cervical NENs, respectively. EPH-A4 showed positive expression in 9/11 pancreatic, 4/4 small intestine, 3/3 lung specimens and EPH-A5 in 10/11, 4/4 and 4/4, respectively. Data retrieved from the systematic review of the literature in combination with the data from the present study are suggestive of a frequent EPH expression in pituitary, thyroid, lung and gastroenteropancreatic NENs, yet, with varying expressions of the single receptor subtypes.

CONCLUSION

EPHs may have a role in NEN tumorigenesis, prognosis as well as a role in the evolving molecular-targeted therapies.

The diagnostic value of serum Ephrin-A1 in patients with colorectal cancer

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide, with a high incidence rate and mortality. The analysis of serum biomarkers for colorectal cancer diagnosis has attracted more and more attention because of its low cost, repeatability, and quantification. This study was aimed to evaluate the diagnostic performance of serum Ephrin-A1 in patients with CRC. We retrospectively analyzed CRC cases in a test cohort (121 patients and 108 controls) and validated them in a validation cohort (119 patients and 118 controls). The concentration of Ephrin-A1 in serum was detected by Enzyme-linked immunosorbent assay (ELISA) and the diagnostic performance of serum Ephrin-A1 was evaluated by receiver operating characteristic (ROC) analysis. In the test cohort, serum Ephrin-A1 levels in patients with all-stage CRC and early-stage CRC were significantly higher than those in healthy controls. The area under the ROC curve (AUC), sensitivity and specificity of all-stage CRC and early-stage CRC were 0.709 (95% CI 0.644-0.775) and 0.660 (95% CI 0.530-0.790), 48.76% and 45.00%, 81.48% and 81.48%, respectively. Similar results were observed in the validation cohort. Serum Ephrin-A1 might be served as a potential biomarker in the diagnosis of CRC.

Exploration of the shared pathways and common biomarkers in cervical and ovarian cancer using integrated bioinformatics analysis

OBJECTIVE

Searching for potential biomarkers and therapeutic targets for early diagnosis of gynecological tumors to improve patient survival.

METHODS

Microarray datasets of cervical cancer (CC) and ovarian cancer (OC) were downloaded from the Gene Expression Omnibus (GEO) database, then, differential gene expression between cancerous and normal tissues in the datasets was analyzed. Weighted gene co-expression network analysis (WGCNA) was performed to screen for co-expression modules associated with CC and OC. The screened shared genes were then further analyzed for functional pathway enrichment. Next, the least absolute shrinkage and selection operator (LASSO) with tenfold cross validation is used to further screened for common diagnostic biomarkers for the two diseases, and further validation is performed using two independent GEO datasets. Finally, the CIBERSORT algorithm was used to estimate the immune infiltration levels of CC and OC, and the correlation between immune cell infiltration and common biomarkers was explored.

RESULTS

After crossing the common DEGs detected by "Limma" R package with the common module genes identified by WGCNA, 44 shared genes were obtained. Functional enrichment indicates that these shared genes are mainly related to DNA synthesis pathways. Lasso regression analysis revealed that EFNA1, TYMS, and WISP2 were co-diagnostic markers for CC and OC, and then based on their expression levels and diagnostic efficacy, EFNA1 was selected as the best co-marker for CC and OC. Immune infiltration analysis shows that the immune environment has a significant impact on the occurrence and development of CC and OC, and the expression of EFNA1 is related to changes in immune cells. Gene-drug interaction analyses identified 27 common drug compounds that interact with candidate genes.

CONCLUSION

This study adopted bioinformatics methods to investigate the common pathways and identify diagnostic markers between CC and OC, suggesting that DNA synthesis and immune environment are closely related to the occurrence and development of CC and OC. EFNA1 may be a potential diagnostic indicator and therapeutic target for patients with CC and OC.

Single-cell RNA sequencing unveils tumor heterogeneity and immune microenvironment between subungual and plantar melanoma

Acral melanoma (AM) is a subtype of melanoma with high prevalence in East Asians. AM is characterized by greater aggressiveness and lower survival rates. However, there are still fewer studies on immune mechanisms of AM especially subungual melanoma (SM) versus non-subungual melanoma (NSM). In order to explore tumor heterogeneity and immune microenvironment in different subtypes of AM, we applied single-cell RNA sequencing to 24,789 single cells isolated from the SM and plantar melanoma (PM) patients. Aspects of tumor heterogeneity, melanocytes from PM and SM had significant differences in gene expression, CNV and pathways in which tumor-associated such as NF-kb and Wnt were involved. Regarding the immune microenvironment, PM contained more fibroblasts and T/NK cells. The EPHA3-EFNA1 axis was expressed only in cancer-associated fibroblast (CAF) and melanocytes of PM, and the TIGIT-NECTIN2 axis was expressed in both AM subtypes of T/NK cells and melanocytes. Altogether, our study helps to elucidate the tumor heterogeneity in AM subpopulations and provides potential therapeutic targets for clinical research.

Optogenetic Regulation of EphA1 RTK Activation and Signaling

Eph receptors are ubiquitous class of transmembrane receptors that mediate cell-cell communication, proliferation, differentiation, and migration. EphA1 receptors specifically play an important role in angiogenesis, fetal development, and cancer progression; however, studies of this receptor can be challenging as its ligand, ephrinA1, binds and activates several EphA receptors simultaneously. Optogenetic strategies could be applied to circumvent this requirement for ligand activation and enable selective activation of the EphA1 subtype. In this work, we designed and tested several iterations of an optogenetic EphA1 - Cryptochrome 2 (Cry2) fusion, investigating their capacity to mimic EphA1-dependent signaling in response to light activation. We then characterized the key cell signaling target of MAPK phosphorylation activated in response to light stimulation. The optogenetic regulation of Eph receptor RTK signaling without the need for external stimulus promises to be an effective means of controlling individual Eph receptor-mediated activities and creates a path forward for the identification of new Eph-dependent functions.

EphrinB2: Expression of a novel potential target in renal cell carcinoma

Introduction

Renal cell carcinoma (RCC) is primarily managed by surgery with the use of systemic targeted therapy in a metastatic setting. Newer targeted therapeutic options are evolving; Eph-ephrin is a potential new pathway. The therapeutic potential of targeting the EphB4-EphrinB2 pathway has been demonstrated in many solid tumors; however, its expression in RCC has only been evaluated in a few studies with limited cases. We herein determine the immunohistochemical expression of EphrinB2 in RCC.

Methods

A tissue microarray comprising 110 cases of different histological subtypes of RCC and 10 normal kidney tissues were stained with monoclonal anti-EphrinB2 antibody (Abcam, AB201512). The tumor and endothelial cells expressing the EphrinB2 were examined and its expression was correlated with sex, histological subtypes, and tumor nodes metastasis (TNM) stage.

Results

Twenty cases of urothelial carcinoma and two unsatisfactory conventional clear cell RCC cases were excluded, and EphrinB2 expression was interpreted in the remaining 88 tumors. EphrinB2 was expressed in 42 out of 88 tumors (47.7%) and was negative in the normal renal parenchyma. There was a statistically significant difference in the expression of EphrinB2 in males (55%) and females (32%). However, no such difference of expression was noted for the histological subtypes and the stages. Half (51%) of Stage 1 (n = 30) and Stage 2 (n = 11) tumors showed EphrinB2 positivity.

Conclusions

EphrinB2 is expressed in approximately half of RCC cases. EphrinB2 expression in the early stage cancer might indicate its induction as an early event.

A genome-wide association study with tissue transcriptomics identifies genetic drivers for classic bladder exstrophy

Classic bladder exstrophy represents the most severe end of all human congenital anomalies of the kidney and urinary tract and is associated with bladder cancer susceptibility. Previous genetic studies identified one locus to be involved in classic bladder exstrophy, but were limited to a restrict number of cohort. Here we show the largest classic bladder exstrophy genome-wide association analysis to date where we identify eight genome-wide significant loci, seven of which are novel. In these regions reside ten coding and four non-coding genes. Among the coding genes is EFNA1, strongly expressed in mouse embryonic genital tubercle, urethra, and primitive bladder. Re-sequence of EFNA1 in the investigated classic bladder exstrophy cohort of our study displays an enrichment of rare protein altering variants. We show that all coding genes are expressed and/or significantly regulated in both mouse and human embryonic developmental bladder stages. Furthermore, nine of the coding genes residing in the regions of genome-wide significance are differentially expressed in bladder cancers. Our data suggest genetic drivers for classic bladder exstrophy, as well as a possible role for these drivers to relevant bladder cancer susceptibility.

A genome-wide association study on classic bladder exstrophy reveals eight genome-wide significant loci, most of which contained genes expressed in embryonic developmental bladder stages.

RNA-Seq transcriptome analysis reveals Maackia amurensis leukoagglutinin has antitumor activity in human anaplastic thyroid cancer cells

Background

Lectins are carbohydrate-binding molecules that can bind specifically to the sugar residues of glycoconjugates and are found in almost all organisms. Plant lectins subjected to many studies reported exhibiting anti-cancer activity. This study aimed to investigate the possible molecular mechanisms of Maackia amurensis leukoagglutinin II (MAL-II) treated ATCCs.

Methods and results

We tested the effects of MAL-II, which is isolated from Amur seeds, on cancerous features of 8505C human anaplastic thyroid cancer cells (ATCCs) on a large scale using RNA-Seq. Transcriptome analysis was performed using Illumina next-generation sequencing technology by using cDNA libraries obtained from total RNA isolates of ATCCs treated with 0.25 µM MAL-II for 24 h. Gene ontology and pathway enrichment analysis were performed for the systematic analysis of gene functions. Moreover, we validated RNA-Seq findings using qPCR. Our results showed that many cancer-related genes such as TENM4, STIM2, SYT12, PIEZO2, ABCG1, SPNS2, ARRB1, and IRX5 were downregulated and many anticancer genes such as HSPA6, G0S2, TNFAIP3, GEM, GADD45G, RND1, SERPINB2, and IL24 were upregulated. Also, pathway enrichment analysis showed that differentially expressed genes were found to be associated with Ras, p53, and apoptosis signaling pathways, which are some important signal transduction pathways in development, proliferation, stem cell control, and carcinogenesis.

Conclusion

Collectively, our results show that MAL-II treatment reveals significant antitumor activity by changing the expression of many cancer-related genes and implies that MAL-II treatment might be a potential candidate molecule to inhibit the malignancy of human anaplastic thyroid cancer.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11033-022-07759-6.

Kinase activity profiling in renal cell carcinoma, benign renal tissue and in response to four different tyrosine kinase inhibitors

Kinase activity is frequently altered in renal cell carcinoma (RCC), and tyrosine kinase inhibitors (TKIs) are part of the standard treatment strategy in patients with metastatic disease. However, there are still no established biomarkers to predict clinical benefits of a specific TKI. Here, we performed protein tyrosine kinase (PTK) profiling using PamChip^® technology. The aim of this study was to identify differences in PTK activity between normal and malignant kidney tissue obtained from the same patient, and to investigate the inhibitory effects of TKIs frequently used in the clinics: sunitinib, pazopanib, cabozantinib and tivozanib. Briefly, our results showed that 36 kinase substrates differs (FDR < 0.05) between normal and cancer kidney tissue, where members of the Src family kinases and the phosphoinositide-3-kinase (PI3K) pathway exhibit high activity in renal cancer. Furthermore, ex vivo treatment of clear cell RCC with TKIs revealed that pathways such as Rap1, Ras and PI3K pathways were strongly inhibited, whereas the neurotrophin pathway had increased activity upon TKI addition. In our assay, tivozanib and cabozantinib exhibited greater inhibitory effects on PTK activity compared to sunitinib and pazopanib, implying they might be better suitable as TKIs for selected RCC patients.

Effects of EFNA1 on cell phenotype and prognosis of esophageal carcinoma

Background

To investigate the expression and clinical significance of EFNA1 in broad-spectrum tumors, and to evaluate its relationship with prognosis and biological functions of esophageal carcinoma (ESCA).

Methods

EFNA1 expression in various cancers was analyzed according to the data in the TCGA database. The clinical data were integrated, to analyze the relationship with ESCA clinical parameters and prognosis, and EFNA1 expression in ESCA tissue samples was detected by immunohistochemistry (IHC). Based on bioinformatics, the functional background of EFNA1 overexpression was analyzed. EFNA1 knockout cell model was established by EFNA1-shRNA transfecting ESCA cells, and the effect of knocking down EFNA1 on the proliferation of ESCA cells was detected by MTT.

Results

Among 7563 samples from TCGA, the EFNA1 gene highly expressed in 15 samples with common cancers and endangered the prognosis of patients with tumors. Its overexpression in ESCA and its influence on the prognosis were most significant. EFNA1 expression in 80 samples with ESCA and their paired samples was tested by IHC to verify its high expression (paired t test, P < 0.001) in ESCA tissues. It was found that EFNA1 expression was related to clinical factors (TNM staging, P = 0.031; lymph node metastasis, P = 0.043; infiltration, P = 0.016). Meanwhile, EFNA1 was found to be an independent risk factor based on the COX multi-factor analysis. And to further explore the importance of EFNA1 in tumors, EC-9706 and ECA109 cells were screened from 8 ESCA-related cell lines to build EFNA1 knockdown cell models. The results showed that EFNA1 knockdown significantly inhibited the proliferation of tumor cells (P < 0.05). In terms of molecular mechanism, EFNA1 related genes were significantly enriched in the proliferative pathway according to the pathway enrichment analysis. It was found that knocking down EFNA1 did inhibit cell proliferation based on cell experiments.

Conclusions

EFNA1 overexpression in ESCA tissue is related to the prognosis of patients. Knocking down EFNA1 can significantly inhibit the proliferation of ESCA cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02362-8.

The Clinical Impact of the EPH/Ephrin System in Cancer: Unwinding the Thread

Erythropoietin-producing human hepatocellular receptors (EPHs) compose the largest known subfamily of receptor tyrosine kinases (RTKs). They bind and interact with the EPH family receptor interacting proteins (ephrins). EPHs/ephrins are implicated in a variety of physiological processes, as well as in cancer pathogenesis. With neoplastic disease remaining a leading cause of death world-wide, the development of novel biomarkers aiding in the field of diagnosis, prognosis, and disease monitoring is of utmost importance. A multitude of studies have proven the association between the expression of members of the EPH/ephrin system and various clinicopathological parameters, including disease stage, tumor histologic grade, and patients' overall survival. Besides their utilization in timely disease detection and assessment of outcome, EPHs/ephrins could also represent possible novel therapeutic targets. The aim of the current review of the literature was to present the existing data regarding the association between EPH/ephrin system expression and the clinical characteristics of malignant tumors.

Comprehensive analysis of the expression and prognosis for TNFAIPs in head and neck cancer

Head and neck cancer (HNC) tumorigenesis involves a combination of multiple genetic alteration processes. Tumour necrosis factor-alpha-induced proteins (TNFAIPs) are involved in tumour development and progression, but few studies have been conducted on these factors in HNC. We aimed to analyse TNFAIPs and assess their potential as prognostic biomarkers and therapeutic targets using the Oncomine, UALCAN, Human Protein Atlas, LinkedOmics, cBioPortal, GeneMANIA, Enrichr, and Tumor IMmune Estimation Resource databases. We found that the transcript levels of TNFAIP1, TNFAIP3, EFNA1, TNFAIP6 and TNFAIP8 were increased, while those of TNFAIP8L3 and STEAP4 were reduced in HNC tissues versus normal tissues. The EFNA1, TNFAIP8 and TNFAIP8L3 expression levels were significantly correlated with the pathological stage. In HNC patients, high PTX3 and TNFAIP6 transcript levels were significantly associated with shorter overall survival (OS). Moreover, genetic alterations in TNFAIP1, TNFAIP6, and STEAP4 resulted in poorer disease-free survival, progression-free survival, and OS, respectively. TNFAIPs may mediate HNC tumorigenesis by regulating PI3K-Akt, Ras and other signalling pathways. TNFAIPs are also closely correlated with the infiltration of immune cells, including B cells, CD8⁺ T cells, CD4⁺ T cells, etc. The data above indicate that TNFAIPs may be potential biomarkers and therapeutic targets for HNC.

EFNA1 is a potential key gene that correlates with immune infiltration in low-grade glioma

EFNA1 is a key gene that is associated with the pathogenesis of several human cancers. However, the prognostic role of EFNA1 in many cancers and the relationship between EFNA1 and tumor-infiltrating lymphocytes in different cancers remain unclear.The expression levels of EFNA1 in 33 types of cancer in the TCGA (The Cancer Genome Atlas) database were collected via the UCSC Xena browser. The clinical data of LGG (low grade glioma) patients were downloaded from the TCGA database. The glioma data from the CGGA (Chinese Glioma Genome Atlas) database were also downloaded to verify the results. Kaplan-Meier and Cox regression analyses were used to investigate the prognostic value of EFNA1 in different cancers using R software. We verified the differential expression of EFNA1 in glioma and normal brain tissue via gene expression profiling interactive analysis. We evaluated the relationship between the expression level of EFNA1 and the clinicopathological features of LGG patients via the Wilcoxon signed-rank test. The immune infiltration levels were evaluated via tumor immune estimation resource (TIMER) and CIBERSORT, and the correlations between EFNA1 and immune cell levels were investigated via TIMER. Finally, we conducted gene set enrichment analysis (GSEA) to explore the potential mechanisms.Data from the TCGA database showed that EFNA1 was differentially expressed in many kinds of cancers when compared with normal tissues. Upregulated EFNA1 expression in esophageal carcinoma (ESCA), cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC), and LGG correlated with shorter patient overall survival (OS) times. The Cox regression analysis revealed that the expression of EFNA1 was also a risk factor for the disease-specific survival (DSS) and progression-free interval (PFI) of LGG patients. The multiple Cox regression analysis revealed that EFNA1 was an independent prognostic factor for LGG patients. In addition, EFNA1 expression was increased in the WHO grade III group and the 1p19q non-codeletion group. Moreover, EFNA1 expression was positively correlated with the levels of infiltrating CD4+ T cells, myeloid dendritic cells and neutrophils in LGG. GSEA suggested that several GO and kyoto encyclopedia of genes and genomes (KEGG) items associated with nervous system function and apoptotic pathway were significantly enriched in the EFNA1-low and EFNA1-high expression phenotypes.EFNA1 may play a pivotal role in the development of LGG and may serve as a potential marker for LGG prognosis and therapy.

Role of EFNA1 in tumorigenesis and prospects for cancer therapy

Cancer is one of the major threats to human health. It is of vital importance to reveal the mechanisms of tumorigenesis, identify effective biomarkers and develop novel treatments to improve patient outcome. EFNA1 (ephrinA1) is a member of the EFN family, and it has been studied extensively since its discovery in 1990. Increasing evidence indicates that EFNA1 plays a pivotal role in the pathogenesis of tumors. We provide a detailed overview of the expression and prognostic value of EFNA1 in different types of human malignancies. We briefly discuss the mechanisms of EFNA1 induction in hypoxic environments and its pro-angiogenic function in different cancer cells. We describe the effects of EFNA1 on tumor growth, invasiveness and metastasis. We summarize recent advances in EFNA1-associated cancer therapeutics with emphasis on the prospect of novel anti-tumor methods based on EFNA1.

Overexpressed gene signature of EPH receptor A/B family in cancer patients-comprehensive analyses from the public high-throughput database

Although a previous study suggested that erythropoietin-producing hepatoma (EPH) receptors play important roles in tumor progression and the overexpression of EPHs in cancer patients is related to poor prognoses, high-throughput gene expression profiling of EPH family members in different types and subtypes of cancers has so far not been conducted. We herein carried out a series of bioinformatic analyses on expressive profiles of every EPH member across 21 different types of clinical cancers versus matched normal tissues gathered from the Oncomine platform. We validated these results by protein expression study of all EPHs family members by The Human Protein Atlas repository. Our results uncovered the overexpression of most EPH subunits in numerous cancer types, especially the dramatic overexpression of six EPHs members, namely EPHA1, EPHA2, EPHA3, EPHA4 and EPHB1, EPHB2, EPHB3, EPHB4 in bladder, colorectal, esophageal, gastric, and prostate cancers. Furthermore, EPHB2 was specifically highly expressed in cervical cancer, EPHA3 in liver cancer, and EPHB1 in uterine cancer. Collectively, expressive profiles of these EPHs were confirmed and correlated with different cancer subtypes as potential biomarkers. This study provides useful information for further studies on cancer development and clinical treatments.

Cancer-associated fibroblasts promote gastric tumorigenesis through EphA2 activation in a ligand-independent manner

PURPOSE

Under physiologic conditions, the binding of erythropoietin-producing hepatocellular (Eph) A2 receptor and its ligand ephrinA1 results in decreased EphA2 level and tumor suppression. However, EphA2 and ephrinA1 are highly expressed in human cancers including gastric adenocarcinoma. In this study, we tested our hypothesis that cancer-associated fibroblasts (CAFs) promote gastric tumorigenesis through EphA2 signaling in a ligand-independent manner.

METHODS

Expression of EphA2 protein in primary tumor tissues of 91 patients who underwent curative surgery for gastric adenocarcinoma was evaluated by immunohistochemistry and western blotting. Conditioned medium of cancer-associated fibroblasts (CAF-CM) was used to evaluate the tumorigenic effect of CAFs on gastric cancer cell lines. Epithelial-mesenchymal transition (EMT), cell proliferation, migration, and invasion were assessed. EphrinA1-Fc ligand was used to determine the suppressor role of EphA2 receptor-ligand binding.

RESULTS

CAF-CM-induced EMT and promoted cancer cell motility even without cell-cell interaction. Treatment with a selective EphA2 inhibitor (ALW-II-41-27) or EphA2-targeted siRNA markedly reduced CAF-CM-induced gastric tumorigenesis. EphrinA1-Fc ligand treatment showing ligand-dependent tumor suppression diminished the EphA2 expression and EMT progression. In contrast, ephrinA1-targeted siRNA did not significantly affect CAF-CM-mediated increases in EphA2 expression and EMT progression. Treatment with VEGF showed effects like CAF-CM in terms of EphA2 activation and EMT progression.

CONCLUSION

CAFs may contribute to gastric tumorigenesis by activating EphA2 signaling pathway in a ligand-independent manner. Our results suggest that ligand-independent activation of EphA2 was triggered by VEGF released from CAF-CM. Our result may partially explain why ligand-dependent tumor suppressor roles of EphA2 are not evident in gastric cancer despite the prominent level of ephrinA1.

Tumor-suppressing effects of microRNA-429 in human renal cell carcinoma via the downregulation of Sp1

MicroRNA (miR)-429 has been frequently reported to be downregulated in various tumors, including renal cell carcinoma (RCC), nasopharyngeal carcinoma, Ehrlich ascites tumor cells, gastric cancer, non-small cell lung cancer and endometrial endometrioid carcinoma. The present study investigated the effects of miR-429 on human RCC A498 and 786-O cells. Following transfection of cells with miR-429 mimics and scrambled control, MTT, cell migration, cell invasion and luciferase assays were performed. In addition, western blotting was performed in order to assess the expression of specificity protein 1 (Sp1), which was predicted to be a target of miR-429 by TargetScan. The present results revealed that miR-429 inhibited cell proliferation, migration and invasion of 786-O and A498 cells. In addition, the present results demonstrated that miR-429 overexpression downregulated Sp1 protein expression, which provides evidence that miR-429 may directly target Sp1 in RCC. These results suggest that miR-429 may be investigated for use as a predictive marker for early detection of tumor metastasis and blocking RCC cells from becoming invasive.

Unusual Suspects in the Twilight Zone Between the Hsp90 Interactome and Carcinogenesis

The molecular chaperone Hsp90 has attracted a lot of interest in cancer research ever since cancer cells were found to be more sensitive to Hsp90 inhibition than normal cells. Why that is has remained a matter of debate and is still unclear. In addition to increased Hsp90 dependence for some mutant cancer proteins and modifications of the Hsp90 machinery itself, a number of other characteristics of cancer cells probably contribute to this phenomenon; these include aneuploidy and overall increased numbers and levels of defective and mutant proteins, which all contribute to perturbed proteostasis. Work over the last two decades has demonstrated that many cancer-related proteins are Hsp90 clients, and yet only few of them have been extensively investigated, selected either on the basis of their obvious function as cancer drivers or because they proved to be convenient biomarkers for monitoring the effects of Hsp90 inhibitors. The purpose of our review is to go beyond these "usual suspects." We established a workflow to select poorly studied proteins that are related to cancer processes and qualify as Hsp90 clients. By discussing and taking a fresh look at these "unusual suspects," we hope to stimulate others to revisit them as novel therapeutic targets or diagnostic markers.

The effect of ephrin-A1 on resistance to Photofrin-mediated photodynamic therapy in esophageal squamous cell carcinoma cells

Esophageal squamous cell carcinoma (ESCC), the most prevalent cell type of esophageal cancer, remains a dismal disease with poor prognosis. Photodynamic therapy (PDT) is a minimally invasive treatment option for early esophageal cancer. To explore possible factors involved in resistance to PDT in esophageal cancer cells, we selected PDT-resistant subcell lines by repeated treatment of CE48T/VGH (CE48T) ESCC cells with Photofrin-PDT and then analyzed the global gene modulations in the PDT-resistant cells by whole-genome microarray. More than 700 genes reached a fold change greater than 1.5 in each of the PDT-resistant cells compared to parental cells. Among these genes, both tumor necrosis factor (TNF) and EFNA1 genes were significantly upregulated in resistant cell lines. However, they were significantly downregulated in Photofrin-PDT-treated cells compared to untreated cells. The observations made in the microarray analysis were further confirmed by quantitative PCR. We observed that recombinant tumor necrosis factor alpha (TNF-α) activated the gene expression of EFNA1 at both the messenger RNA (mRNA) level and the protein level in CE48T cells. Functional analysis showed that when incubated with oligomeric and monomeric ephrin-A1 simultaneously, ESCC cells became significantly resistant to Photofrin-PDT. Functional analysis further suggested that transmembrane and soluble ephrin-A1 may cooperate to enhance resistance to Photofrin-PDT in ESCC cells.

Upregulation of microRNA-204 inhibits cell proliferation, migration and invasion in human renal cell carcinoma cells by downregulating SOX4

MicroRNA-204 (miR-204) has been reported to be frequently downregulated in various types of cancer, including renal, brain, ovary, hematological and colon cancer. The present study, investigated the effects of miR‑204 on renal cell carcinoma. Following transfection of miR‑204, an MTT assay, cell migration assay, cell invasion assay, western blot analysis and luciferase assay were performed in renal cell carcinoma cell lines. It was demonstrated that miR‑204 inhibits cell proliferation, migration and invasion in 786‑O and A498 cells. To the best of our knowledge, this study is the first to demonstrate that miR‑204 directly targets SOX4 in renal cell carcinoma. These results suggested that miR-204 may have value as a marker for the early detection of tumor metastasis and a therapeutic target preventing the invasion of renal cell carcinoma.

Signaling involved in stem cell reprogramming and differentiation

Stem cell differentiation is regulated by multiple signaling events. Recent technical advances have revealed that differentiated cells can be reprogrammed into stem cells. The signals involved in stem cell programming are of major interest in stem cell research. The signaling mechanisms involved in regulating stem cell reprogramming and differentiation are the subject of intense study in the field of life sciences. In this review, the molecular interactions and signaling pathways related to stem cell differentiation are discussed.

Prognostic role of EphA2 in various human carcinomas: a meta-analysis of 23 related studies

The prognostic role of EphA2 in human carcinomas remains controversial. We systematically reviewed the evidence of assessment of EphA2 expression in cancers to help clarify this issue. PubMed, Embase and Web of Science databases were searched to identify eligible studies to evaluate the association of EphA2 expression and overall survival (OS) of cancers. Hazard ratios (HRs) were pooled to estimate the effect. EphA2 overexpression was significantly correlated with poor OS of patients with cancer (HR: 1.94, 95% confidence interval [CI]: 1.65-2.28). Subgroup analysis also indicated a significant relation between EphA2 overexpression and OS in gastric cancer (HR: 1.95, 95% CI: 1.48-2.59). However, there was no significant relation between EphA2 overexpression and OS in lung cancer (HR: 1.30, 95% CI: 0.93-1.83). Our analyses demonstrate that EphA2 overexpression was effectively predictive of worse prognosis in various human carcinomas. For certain cancers, EphA2 might be a marker of poor prognosis in patients with cancer, except for lung cancer.

Eph family co-expression patterns define unique clusters predictive of cancer phenotype

The Eph genes are the largest sub-family of receptor tyrosine kinases; however, it is most likely the least understood and the arena for many conflicting reports. In this tribute to Prof. Martin Lackmann and Prof. Tony Pawson, we utilized The Cancer Genome Atlas resources to shed new light on the understanding of this family. We found that mutation and expression analysis define two clusters of co-expressed Eph family genes that relate to aggressive phenotypes across multiple cancer types. Analysis of signal transduction pathways using reverse-phase protein arrays revealed a network of interactions, which associates cluster-specific Eph genes with epithelial-mesenchymal transition, metabolism, DNA-damage repair and apoptosis. Our findings support the role of the Eph family in modulating cancer progression and reveal distinct patterns of Eph expression, which correlate with disease outcome. These observations provide further rationale for seeking cancer therapies, which target the Eph/ephrin system.