High-level S100A6 promotes metastasis and predicts the outcome of T1-T2 stage in clear cell renal cell carcinoma

The Role of S100A6 in Human Diseases: Molecular Mechanisms and Therapeutic Potential

S100A6, also known as calcyclin, is a low-molecular-weight Ca2+-binding protein from the S100 family that contains two EF-hands. S100A6 is expressed in a variety of mammalian cells and tissues. It is also expressed in lung, colorectal, pancreatic, and liver cancers, as well as other cancers such as melanoma. S100A6 has many molecular functions related to cell proliferation, the cell cycle, cell differentiation, and the cytoskeleton. It is not only involved in tumor invasion, proliferation, and migration, but also the pathogenesis of other non-neoplastic diseases. In this review, we focus on the molecular mechanisms and potential therapeutic targets of S100A6 in tumors, nervous system diseases, leukemia, endometriosis, cardiovascular disease, osteoarthritis, and other related diseases.

A transcriptional metastatic signature predicts survival in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common type of kidney cancer in adults. When ccRCC is localized to the kidney, surgical resection or ablation of the tumor is often curative. However, in the metastatic setting, ccRCC remains a highly lethal disease. Here we use fresh patient samples that include treatment-naive primary tumor tissue, matched adjacent normal kidney tissue, as well as tumor samples collected from patients with bone metastases. Single-cell transcriptomic analysis of tumor cells from the primary tumors reveals a distinct transcriptional signature that is predictive of metastatic potential and patient survival. Analysis of supporting stromal cells within the tumor environment demonstrates vascular remodeling within the endothelial cells. An in silico cell-to-cell interaction analysis highlights the CXCL9/CXCL10-CXCR3 axis and the CD70-CD27 axis as potential therapeutic targets. Our findings provide biological insights into the interplay between tumor cells and the ccRCC microenvironment.

Curcuminoids as Modulators of EMT in Invasive Cancers: A Review of Molecular Targets With the Contribution of Malignant Mesothelioma Studies

Curcuminoids, which include natural acyclic diarylheptanoids and the synthetic analogs of curcumin, have considerable potential for fighting against all the characteristics of invasive cancers. The epithelial-to-mesenchymal transition (EMT) is a fundamental process for embryonic morphogenesis, however, the last decade has confirmed it orchestrates many features of cancer invasiveness, such as tumor cell stemness, metabolic rewiring, and drug resistance. A wealth of studies has revealed EMT in cancer is in fact driven by an increasing number of parameters, and thus understanding its complexity has now become a cornerstone for defining future therapeutic strategies dealing with cancer progression and metastasis. A specificity of curcuminoids is their ability to target multiple molecular targets, modulate several signaling pathways, modify tumor microenvironments and enhance the host’s immune response. Although the effects of curcumin on these various parameters have been the subject of many reviews, the role of curcuminoids against EMT in the context of cancer have never been reviewed so far. This review first provides an updated overview of all EMT drivers, including signaling pathways, transcription factors, non-coding RNAs (ncRNAs) and tumor microenvironment components, with a special focus on the most recent findings. Secondly, for each of these drivers the effects of curcumin/curcuminoids on specific molecular targets are analyzed. Finally, we address some common findings observed between data reported in the literature and the results of investigations we conducted on experimental malignant mesothelioma, a model of invasive cancer representing a useful tool for studies on EMT and cancer.

Biomarkers of tumor invasiveness in proteomics (Review)

Over the past two decades, quantitative proteomics has emerged as an important tool for deciphering the complex molecular events involved in cancers. The number of references involving studies on the cancer metastatic process has doubled since 2010, while the last 5 years have seen the development of novel technologies combining deep proteome coverage capabilities with quantitative consistency and accuracy. To highlight key findings within this huge amount of information, the present review identified a list of tumor invasive biomarkers based on both the literature and data collected on a biocollection of experimental cell lines, tumor models of increasing invasiveness and tumor samples from patients with colorectal or breast cancer. Crossing these different data sources led to 76 proteins of interest out of 1,245 mentioned in the literature. Information on these proteins can potentially be translated into clinical prospects, since they represent potential targets for the development and evaluation of innovative therapies, alone or in combination. Herein, a systematical review of the biology of each of these proteins, including their specific subcellular/extracellular or multiple localizations is presented. Finally, as an important advantage of quantitative proteomics is the ability to provide data on all these molecules simultaneously in cell pellets, body fluids or paraffin‑embedded sections of tumors/invaded tissues, the significance of some of their interconnections is discussed.

CancerSEA: a cancer single-cell state atlas

High functional heterogeneity of cancer cells poses a major challenge for cancer research. Single-cell sequencing technology provides an unprecedented opportunity to decipher diverse functional states of cancer cells at single-cell resolution, and cancer scRNA-seq datasets have been largely accumulated. This emphasizes the urgent need to build a dedicated resource to decode the functional states of cancer single cells. Here, we developed CancerSEA (http://biocc.hrbmu.edu.cn/CancerSEA/ or http://202.97.205.69/CancerSEA/), the first dedicated database that aims to comprehensively explore distinct functional states of cancer cells at the single-cell level. CancerSEA portrays a cancer single-cell functional state atlas, involving 14 functional states (including stemness, invasion, metastasis, proliferation, EMT, angiogenesis, apoptosis, cell cycle, differentiation, DNA damage, DNA repair, hypoxia, inflammation and quiescence) of 41 900 cancer single cells from 25 cancer types. It allows querying which functional states are associated with the gene (or gene list) of interest in different cancers. CancerSEA also provides functional state-associated PCG/lncRNA repertoires across all cancers, in specific cancers, and in individual cancer single-cell datasets. In summary, CancerSEA provides a user-friendly interface for comprehensively searching, browsing, visualizing and downloading functional state activity profiles of tens of thousands of cancer single cells and the corresponding PCGs/lncRNAs expression profiles.

Changes in Serum and Salivary Proteins in Canine Mammary Tumors

The aim of this study was to evaluate changes in serum and saliva proteomes in canine mammary tumors (CMT) using a high-throughput quantitative proteomic analysis in order to potentially discover possible biomarkers of this disease. Proteomes of paired serum and saliva samples from healthy controls (HC group, n = 5) and bitches with CMT (CMT group, n = 5) were analysed using a Tandem Mass Tags-based approach. Twenty-five dogs were used to validate serum albumin as a candidate biomarker in an independent sample set. The proteomic analysis quantified 379 and 730 proteins in serum and saliva, respectively. Of those, 35 proteins in serum and 49 in saliva were differentially represented. The verification of albumin in serum was in concordance with the proteomic data, showing lower levels in CMT when compared to the HC group. Some of the modulated proteins found in the present study such as haptoglobin or S100A4 have been related to CMT or human breast cancer previously, while others such as kallikrein-1 and immunoglobulin gamma-heavy chains A and D are described here for the first time. Our results indicate that saliva and serum proteomes can reflect physiopathological changes that occur in CMT in dogs and can be a potential source of biomarkers of the disease.

Integrative Radiogenomics Approach for Risk Assessment of Post-Operative Metastasis in Pathological T1 Renal Cell Carcinoma: A Pilot Retrospective Cohort Study

Despite the increasing incidence of pathological stage T1 renal cell carcinoma (pT1 RCC), postoperative distant metastases develop in many surgically treated patients, causing death in certain cases. Therefore, this study aimed to create a radiomics model using imaging features from multiphase computed tomography (CT) to more accurately predict the postoperative metastasis of pT1 RCC and further investigate the possible link between radiomics parameters and gene expression profiles generated by whole transcriptome sequencing (WTS). Four radiomic features, including the minimum value of a histogram feature from inner regions of interest (ROIs) (INNER_Min_hist), the histogram of the energy feature from outer ROIs (OUTER_Energy_Hist), the maximum probability of gray-level co-occurrence matrix (GLCM) feature from inner ROIs (INNER_MaxProb_GLCM), and the ratio of voxels under 80 Hounsfield units (Hus) in the nephrographic phase of postcontrast CT (Under80HURatio), were detected to predict the postsurgical metastasis of patients with pathological stage T1 RCC, and the clinical outcomes of patients could be successfully stratified based on their radiomic risk scores. Furthermore, we identified heterogenous-trait-associated gene signatures correlated with these four radiomic features, which captured clinically relevant molecular pathways, tumor immune microenvironment, and potential treatment strategies. Our results of accurate surrogates using radiogenomics could lead to additional benefit from adjuvant therapy or postsurgical metastases in pT1 RCC.

S100A6 activates EGFR and its downstream signaling in HaCaT keratinocytes

Epidermal growth factor receptor (EGFR) is a central transmitter of mitogenic signals in epithelial cells; enhanced EGFR activity is observed in many tumors of epithelial origin. S100A6 is a small calcium-binding protein, characteristic mainly of epithelial cells and fibroblasts, strongly implicated in cell proliferation and upregulated in tumors. In this study, using biochemical assays along with immunohistochemical and immunocytochemical analysis of organotypic and standard cultures of HaCaT keratinocytes with S100A6 overexpression or knock-down, we have examined the effect of S100A6 on EGFR activity and downstream signaling. We found that HaCaT cells overexpressing S100A6 had enhanced EGFR, phospho EGFR, and phospho extracellular signal-regulated kinase 1/2 (pERK1/2) staining intensity and level coupled to higher signal transducer and activator of transcription 3 (STAT3) activity. Conversely, S100A6 knockdown cells had impaired EGFR signaling that could be enhanced by addition of recombinant S100A6 to the culture media. Altogether the results show that S100A6 may exert its proproliferative effects through activating EGFR.

DNA methylation associates with survival in non-metastatic clear cell renal cell carcinoma

Background

Clear cell renal cell carcinoma (ccRCC) is the most common subtype among renal cancer and is associated with poor prognosis if metastasized. Up to one third of patients with local disease at diagnosis will develop metastasis after nephrectomy, and there is a need for new molecular markers to identify patients with high risk of tumor progression. In the present study, we performed genome-wide promoter DNA methylation analysis at diagnosis to identify DNA methylation profiles associated with risk for progress.

Method

Diagnostic tissue samples from 115 ccRCC patients were analysed by Illumina HumanMethylation450K arrays and methylation status of 155,931 promoter associated CpGs were related to genetic aberrations, gene expression and clinicopathological parameters.

Results

The ccRCC samples separated into two clusters (cluster A/B) based on genome-wide promoter methylation status. The samples in these clusters differed in tumor diameter (p < 0.001), TNM stage (p < 0.001), morphological grade (p < 0.001), and patients outcome (5 year cancer specific survival (pCSS_5yr) p < 0.001 and cumulative incidence of progress (pCIP_5yr) p < 0.001. An integrated genomic and epigenomic analysis in the ccRCCs, revealed significant correlations between the total number of genetic aberrations and total number of hypermethylated CpGs (R = 0.435, p < 0.001), and predicted mitotic age (R = 0.407, p < 0.001). We identified a promoter methylation classifier (PMC) panel consisting of 172 differently methylated CpGs accompanying progress of disease. Classifying non-metastatic patients using the PMC panel showed that PMC high tumors had a worse prognosis compared with the PMC low tumors (pCIP_5yr 38% vs. 8%, p = 0.001), which was confirmed in non-metastatic ccRCCs in the publically available TCGA-KIRC dataset (pCIP_5yr 39% vs. 16%, p < 0.001).

Conclusion

DNA methylation analysis at diagnosis in ccRCC has the potential to improve outcome-prediction in non-metastatic patients at diagnosis.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5291-3) contains supplementary material, which is available to authorized users.

Distinct prognostic roles of S100 mRNA expression in gastric cancer

BACKGROUND

The S100 protein family is implicated in tumor invasion and metastasis, but its prognostic roles in gastric cancer (GC) has not been elucidated.

MATERIALS AND METHODS

In the current study, Kaplan-Meier plotter (KM plotter) database integrated the expression data and survival information of 1065 GC patients were downloaded from the Gene Expression Omnibus (GEO) (GSE22377, GSE14210 and GSE51105) that published by the three major cancer centers (Berlin, Bethesda and Melbourne). Then this database was used to explore the prognostic values of mRNA expression of each individual S100 in GC patients. We further assessed the prognostic value of S100 in different Lauren classifications, clinicopathological features and clinical treatment of gastric cancer.

RESULTS

Expression of 12 members of the S100 family correlated with overall survival (OS) for all GC patients. Increased expression of S100A3, S100A5, S100A7, S100A7A, S100A11, S100A13, S100Z and S100 G were found to be strongly associated with worse survival, while S100A8, S100A9, S100B and S100 P were correlated with better prognosis in all GC patients. Further assessment of prognostic values of S100 in gastric cancer with different clinical features indicated that different S100 members may interact with different signaling pathways and exerted different functions in gastric cancer development.

CONCLUSIONS

Although the results should be further testified in clinical studies, our findings offer new insights into the contribution of S100 members to GC progression and might promote development of S100 targeted reagents for treating GC.

S100A6 promotes proliferation of intrahepatic cholangiocarcinoma cells via the activation of the p38/MAPK pathway

Aim: We explored the expression of S100A6 and its role in intrahepatic cholangiocarcinoma (ICC). Methods: The expression of S100A6 in ICC samples was detected by immunohistochemistry. In vitro experiments, we silenced and overexpressed S100A6 to investigate its role in cell functions. Results: The expression of S100A6 was markedly increased in ICC tissues and cell lines. S100A6 overexpression was an independent risk factor for patients’ survival. Silencing S100A6 resulted in a suppression of proliferation and p38/MAPK activity, while overexpressing S100A6 caused a promotion of proliferation and p38/MAPK. Discussion: S100A6 participated in the proliferation of ICC cells and correlated with a more aggressive behavior of ICC. Conclusion: S100A6 may serve as a novel prognostic marker and a potential therapeutic target for ICC patients.

"Stealth dissemination" of macrophage-tumor cell fusions cultured from blood of patients with pancreatic ductal adenocarcinoma

Here we describe isolation and characterization of macrophage-tumor cell fusions (MTFs) from the blood of pancreatic ductal adenocarcinoma (PDAC) patients. The MTFs were generally aneuploidy, and immunophenotypic characterizations showed that the MTFs express markers characteristic of PDAC and stem cells, as well as M2-polarized macrophages. Single cell RNASeq analyses showed that the MTFs express many transcripts implicated in cancer progression, LINE1 retrotransposons, and very high levels of several long non-coding transcripts involved in metastasis (such as MALAT1). When cultured MTFs were transplanted orthotopically into mouse pancreas, they grew as obvious well-differentiated islands of cells, but they also disseminated widely throughout multiple tissues in "stealth" fashion. They were found distributed throughout multiple organs at 4, 8, or 12 weeks after transplantation (including liver, spleen, lung), occurring as single cells or small groups of cells, without formation of obvious tumors or any apparent progression over the 4 to 12 week period. We suggest that MTFs form continually during PDAC development, and that they disseminate early in cancer progression, forming "niches" at distant sites for subsequent colonization by metastasis-initiating cells.

Distinct prognostic values of S100 mRNA expression in breast cancer

S100 family genes encode low molecular weight, acidic-Ca²⁺ binding proteins implicating in a wide spectrum of biological processes. S100 family contains at least 20 members, most of which are frequently dysregulated in human malignancies including breast cancer. However, the prognostic roles of each individual S100, especially the mRNA level, in breast cancer patients remain elusive. In the current study, we used "The Kaplan-Meier plotter" (KM plotter) database to investigate the prognostic values of S100 mRNA expression in breast cancer. Our results indicated that high mRNA expression of S100A8, S100A9, S100A11 and S100P were found to be significantly correlated to worse outcome, while S100A1 and S100A6 were associated with better prognosis in all breast cancer patients. We further assessed the prognostic value of S100 in different intrinsic subtypes and clinicopathological features of breast cancer. The associated results will elucidate the role of S100 in breast cancer and may further lead the research to explore the S100-targeting reagents for treating breast cancer patients.

Increased expression of S100A6 promotes cell proliferation in gastric cancer cells

S100A6 is involved in regulating the progression of cancer. S100A6 can regulate the dynamics of cytoskeletal constituents, cell growth and differentiation by interacting with binding or target proteins. The present study investigated whether S100A6 affects cell proliferation in gastric cancer cells by stimulating several downstream factors. Firstly, the expression and localization of S100A6 were investigated using immunohistochemical staining, an immunoelectron microscopy and laser confocal scanning. A ChIP-Chip assay was performed to determine the downstream factors of S100A6 using promoter Chip analysis, including approximately the −800 to +200 regions around the transcription starting point. Polymerase chain reaction analysis was performed to confirm this. It was found that the intensity of S100A6 staining was markedly higher in the cytoplasm and nucleus, and its expression level correlated with that of the Ki67 protein. The overexpression of S100A6 also promoted cell proliferation in AGS and BGC823 cell lines, detected using a Cell Counting-Kit 8 assay. In cells overexpressing S100A6, the expression levels of interleukin (IL)-8, cyclin-dependent kinase (CDK)5, CDK4, minichromosome maintenance complex component 7 (MCM7) and B-cell lymphoma 2 (Bcl2) were noticeably increased. In conclusion, the increased expression of S100A6 promoted cell proliferation by regulating the expression levels of IL-8, CDK5, CDK4, MCM7 and Bcl2 in gastric cancer cells.

Serum levels of S100A6 are unaltered in patients with resectable cholangiocarcinoma

Background

Elevated expression levels of S100A6, a calcium-binding low-molecular-weight protein, were demonstrated in various malignancies. Moreover, increased serum levels of S100A6 were suggested as a novel biomarker for various inflammatory and malignant diseases including lung and gastric cancer. However, up to now, serum concentrations of S100A6 have not been analyzed in patients with cholangiocarcinoma (CCA).

Methods

S100A6 mRNA expression levels were analyzed in human and murine CCA tumor samples, using semi-quantitative reverse transcriptase PCR. S100A6 serum concentrations were measured using an enzyme-linked immunosorbent assay in 112 patients with CCA referred to surgery for curative resection and were compared to those of 42 healthy controls. Results were correlated with clinical data.

Results

S100A6 mRNA expression levels were significantly up-regulated in tumor samples of CCA patients and in tumor tissue of a CCA mouse model. In contrast, serum levels of S100A6 were not significantly altered in patients with CCA compared to healthy controls. Whereas no differences became apparent within the different clinical subgroups of CCA, patients with primary sclerosing cholangitis (PSC)-based CCA displayed higher levels of S100A6 compared to the other patients. Nevertheless, patients with higher S100A6 serum concentrations showed a trend towards an impaired prognosis compared to patients with lower levels. Finally, within our cohort of patients both the diagnostic and prognostic potentials of S100A6 were similar to those of the clinically established biomarkers CEA and CA19-9.

Conclusion

Although S100A6 was expressed at significantly higher levels in human and murine CCA tumor samples, S100A6 serum levels were not regulated in patients with CCA and are thus not suitable for diagnosis of CCA. However, CCA-patients with elevated S100A6 displayed a trend toward an impaired prognosis compared to patients with lower S100A6 levels, supporting its further evaluation as a prognostic biomarker in CCA.

Electronic supplementary material

The online version of this article (doi:10.1186/s40169-016-0120-7) contains supplementary material, which is available to authorized users.