Relationship and prognostic significance of SPARC and VEGF protein expression in colon cancer

Effects of Exercise-Induced Changes in Myokine Expression on the Tumor Microenvironment

In this narrative review, we summarize the direct and indirect effects that myokines have on the tumor microenvironment. We took studies of various cancer types and species into account. Systematic reviews and meta-analyses that matched the search terms were also considered. We searched databases for six months. As a narrative approach was chosen, no data was analyzed or reanalyzed. The goal of this narrative review is to create an overview on the topic to identify research gaps and answer the questions as to whether myokine expression may be relevant in cancer research in regard to the tumor microenvironment. Six commonly known myokines were chosen. We found strong links between the influence exercise has on interleukin-6, oncostatin M, secreted protein acidic and rich in cysteine, and irisin in the context of tumor progression and inhibition via interactions with the tumor microenvironment. It became clear that the effects of myokines on the tumor microenvironment can vary and contribute to disease progression or regression. Interactions among myokines and immune cells must also be considered and require further investigation. To date, no study has shown a clear connection, while multiple studies suggest further investigation of the topic, similar to the effects of exercise on myokine expression.

Nuclear localization of TET2 requires β-catenin activation and correlates with favourable prognosis in colorectal cancer

Mutation-induced malfunction of ten-eleven translocation methylcytosine dioxygenase 2 (TET2) is widely reported in haematological malignancies. However, the role of TET2 in solid cancers, including colorectal cancer (CRC), is unclear. Here, we found that TET2 malfunction in CRC is mostly due to decreased nuclear localization and that nuclear localization of TET2 is correlated with better survival of patients. To explore the underlying mechanisms, 14 immortalized solid tumour cell lines and 12 primary CRC cell lines were used. TET2 was mostly detected in the nucleus, and it induced significant DNA demethylation and suppressed cell growth by demethylating RORA and SPARC in cell lines like SW480. While in cell lines like SW620, TET2 was observed in the cytosol and did not affect DNA methylation or cell growth. Further examination with immunoprecipitation-mass spectrometry illustrated that β-catenin activation was indispensable for the nuclear localization and tumour suppression effects of TET2. In addition, the β-catenin pathway activator IM12 and the TET2 activator vitamin C were used simultaneously to enhance the effects of TET2 under low-expression conditions, and synergistic inhibitory effects on the growth of cancer were observed both in vitro and in vivo. Collectively, these data suggest that β-catenin-mediated nuclear localization of TET2 is an important therapeutic target for solid tumours.

Clinicopathological and prognostic significance of SPARC expression in gastric cancer: A meta‑analysis and bioinformatics analysis

Secreted protein acidic and rich in cysteine (SPARC) is a member of the extracellular matrix glycoprotein family that binds to calcium ions. It may bind to a variety of proteins in the extracellular matrix and also compete with cell membrane surface receptors for growth. In the present study, the relationship between SPARC expression in gastric cancer tissues and the clinicopathological characteristics and prognosis of patients with gastric cancer were systematically evaluated. A meta-analysis and bioinformatics analysis were performed using the PubMed, Chinese National Knowledge Infrastructure, Kaplan-Meier (KM)-plotter, The Cancer Genome Atlas (TCGA), Gene Expression Profiling Interactive Analysis (GEPIA), University of ALabama at Birmingham CANcer (UALCAN), Human Protein Atlas (HPA) and Timer databases. SPARC was mainly expressed in tumor mesenchymal cells. The meta-analysis indicated that SPARC expression was higher in gastric cancer tissues than in normal tissues. SPARC was associated with the degree of differentiation and distant metastasis. K-M plotter results indicated that high SPARC expression was negatively associated with overall survival, post-progression survival and progression-free survival rates of patients. According to the Oncomine, GEPIA, UALCAN and HPA databases, SPARC mRNA and protein expression was upregulated in gastric cancer vs. normal tissues and was negatively associated with poor patient prognosis. In the TCGA database, univariate analysis indicated that lymph node metastasis and distant metastasis were associated with the prognosis of patients with gastric cancer. Cox multifactorial analysis suggested that high SPARC expression, age and distant metastasis were important factors affecting the survival time of patients with gastric cancer. Analysis with the Timer database indicated that SPARC was closely associated with the proportion of 7 immune-cell infiltrates in gastric cancer. These findings indicated that high expression of SPARC may be a potential marker of tumorigenesis and metastasis in patients with gastric cancer.

Angiogenesis regulators S100A4, SPARC and SPP1 correlate with macrophage infiltration and are prognostic biomarkers in colon and rectal cancers

Introduction

Increasing evidence suggests that it is necessary to find effective and robust clinically validated prognostic biomarkers that can identify "high-risk" colorectal cancer (CRC) patients. Currently, available prognostic factors largely include clinical-pathological parameters and focus on the cancer stage at the time of diagnosis. Among cells of tumor microenvironment (TME) only Immunoscore classifier based on T lymphocytes showed high predictive value.

Methods

In the present study, we performed the complex analysis of mRNA and protein expression of crucial regulators of tumor angiogenesis and tumor progression, expressed by tumor-associated macrophages (TAMs): S100A4, SPP1 and SPARC. Colon and rectal cancer patients were investigated independently and in a combined cohort (CRC). For mRNA expression, we analyzed RNA sequencing data obtained from TCGA (N=417) and GEO (N=92) cohorts of colorectal cancer patients. For protein expression, we performed IHC digital quantification of tumor tissues obtained from 197 patients with CRC treated in the Department of abdominal oncology in Clinics of Tomsk NRMC.

Results

High S100A4 mRNA expression accurately predicted poor survival for patients with CRC independently of cancer type. SPARC mRNA level was independent prognostic factors for survival in colon but not in rectal cancer. SPP1 mRNA level had significant predictive value for survival in both rectal and colon cancers. Analysis of human CRC tissues revealed that S100A4, SPP1 and SPARC are expressed by stromal compartments, in particular by TAMs, and have a strong correlation with macrophage infiltration. Finally, our results indicate that chemotherapy-based treatment can change the predictive direction of S100A4 for rectal cancer patients. We found that S100A4 stromal levels were higher in patients with better response to neoadjuvant chemotherapy/chemoradiotherapy, and S100A4 mRNA levels predicted better DFS among non-responders.

Discussion

These findings can help improve the prognosis of patients with CRC based on S100A4, SPP1 and SPARC expression levels.

Modeling extracellular matrix through histo-molecular gradient in NSCLC for clinical decisions

Lung cancer still represents a global health problem, being the main type of tumor responsible for cancer deaths. In this context, the tumor microenvironment, and the extracellular matrix (ECM) pose as extremely relevant. Thus, this study aimed to explore the prognostic value of epithelial-to-mesenchymal transition (EMT), Wnt signaling, and ECM proteins expression in patients with non-small-cell lung carcinoma (NSCLC) with clinical stages I-IIIA. For that, we used 120 tissue sections from patients and evaluated the immunohistochemical, immunofluorescence, and transmission electron microscopy (TEM) to each of these markers. We also used in silico analysis to validate our data. We found a strong expression of E-cadherin and β-catenin, which reflects the differential ECM invasion process. Therefore, we also noticed a strong expression of chondroitin sulfate (CS) and collagens III and V. This suggests that, after EMT, the basal membrane (BM) enhanced the motility of invasive cells. EMT proteins were directly associated with WNT5A, and collagens III and V, which suggests that the WNT pathway drives them. On the other hand, heparan sulfate (HS) was associated with WNT3A and SPARC, while WNT1 was associated with CS. Interestingly, the association between WNT1 and Col IV suggested negative feedback of WNT1 along the BM. In our cohort, WNT3A, WNT5A, heparan sulfate and SPARC played an important role in the Cox regression model, influencing the overall survival (OS) of patients, be it directly or indirectly, with the SPARC expression stratifying the OS into two groups: 97 months for high expression; and 65 for low expression. In conclusion, the present study identified a set of proteins that may play a significant role in predicting the prognosis of NSCLC patients with clinical stages I-IIIA.

Identification of potential hub genes of gastric cancer

BACKGROUND

Gastric cancer (GC) is a malignant tumor originated from gastric mucosa epithelium. It is the third leading cause of cancer mortality in China. The early symptoms are not obvious. When it is discovered, it has developed to the advanced stage, and the prognosis is poor. In order to screen for potential genes for GC development, this study obtained GSE118916 and GSE109476 from the gene expression omnibus (GEO) database for bioinformatics analysis.

METHODS

First, GEO2R was used to identify differentially expressed genes (DEG) and the functional annotation of DEGs was performed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The Search Tool for the Retrieval of Interacting Genes (STRING) tool was used to construct protein-protein interaction (PPI) network and the most important modules and hub genes were mined. Real time quantitative polymerase chain reaction assay was performed to verify the expression level of hub genes.

RESULTS

A total of 139 DEGs were identified. The functional changes of DEGs are mainly concentrated in the cytoskeleton, extracellular matrix and collagen synthesis. Eleven genes were identified as core genes. Bioinformatics analysis shows that the core genes are mainly enriched in many processes related to cell adhesion and collagen.

CONCLUSION

In summary, the DEGs and hub genes found in this study may be potential diagnostic and therapeutic targets.

RETRACTED ARTICLE: Down-regulation of lncRNA FEZF1-AS1 mediates regulatory T cell differentiation and further blocks immune escape in colon cancer

Statement of RetractionWe, the Editors and Publisher of the journal Expert Review of Molecular Diagnostics, have retracted the following article:Sen Hong, Zhenkun Yan, YuMei Song, MiaoMiao Bi & Shiquan Li. Down-regulation of lncRNA FEZF1-AS1 mediates regulatory T cell differentiation and further blocks immune escape in colon cancer. Expert Review of Molecular Diagnostics. 2021. DOI: 10.1080/14737159.2022.2012157Since publication, significant concerns have been raised about the integrity of the data and reported results in the article. When approached for an explanation, the authors did not provide their original data or any necessary supporting information. As verifying the validity of published work is core to the integrity of the scholarly record, we are therefore retracting the article. The corresponding author listed in this publication has been informed.We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions.The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as 'Retracted'.

Formulation and Characterization of Doxycycline-Loaded Polymeric Nanoparticles for Testing Antitumor/Antiangiogenic Action in Experimental Colon Cancer in Mice

Nanotherapeutics can enhance the characteristics of drugs, such as rapid systemic clearance and systemic toxicities. Polymeric nanoparticles (PRNPs) depend on dispersion of a drug in an amorphous state in a polymer matrix. PRNPs are capable of delivering drugs and improving their safety. The primary goal of this study is to formulate doxycycline-loaded PRNPs by applying the nanoprecipitation method. Eudragit S100 (ES100) (for DOX-PRNP1) and hydroxypropyl methyl cellulose phthalate HP55 (for DOX-PRNP2) were tested as the drug carrying polymers and the DOX-PRNP2 showed better characteristics and drug release % and was hence selected to be tested in the biological study. Six different experimental groups were formed from sixty male albino mice. 1,2,-Dimethylhydrazine was used for 16 weeks to induce experimental colon cancer. We compared the oral administration of DOX-PRNP2 in doses of 5 and 10 mg/kg with the free drug. Results indicated that DOX-PRNP2 had greater antitumor activity, as evidenced by an improved histopathological picture for colon specimens as well as a decrease in the tumor scores. In addition, when compared to free DOX, the DOX-PRNP2 reduced the angiogenic indicators VEGD and CD31 to a greater extent. Collectively, the findings demonstrated that formulating DOX in PRNPs was useful in enhancing antitumor activity and can be used in other models of cancers to verify their efficacy and compatibility with our study.

Secreted Protein Acidic and Rich in Cysteine Mediates the Development and Progression of Diabetic Retinopathy

BACKGROUNDS

Diabetic retinopathy (DR) is one of the most severe microvascular complications of diabetes mellitus (DM). Secreted protein acidic and rich in cysteine (SPARC) has been found to play an important role in many diseases, but its role and mechanism in DR remain unknown.

METHODS

We studied the role of SPARC and integrin β1 in vascular pathophysiology and identified potential therapeutic translation. The SPARC levels were tested in human serum and vitreous by ELISA assay, and then the Gene Expression Omnibus (GEO) dataset was used to understand the key role of the target gene in DR. In human retinal capillary endothelial cells (HRCECs), we analyzed the mRNA and protein level by RT-PCR, immunohistochemistry, and Western blotting. The cell apoptosis, cell viability, and angiogenesis were analyzed by flow cytometry, CCK-8, and tube formation.

RESULTS

In this study, we investigated the role of SPARC in the development and progression of human DR and high glucose-induced HRCEC cells and found that the SPARC-ITGB1 signaling pathway mimics early molecular and advanced neurovascular pathophysiology complications of DR. The result revealed that DR patients have a high-level SPARC expression in serum and vitreous. Knockdown of SPARC could decrease the expressions of inflammatory factors and VEGFR, inhibit cell apoptosis and angiogenesis, and increase cell viability by regulating integrin β1 in HRCECs.

CONCLUSION

SPARC promotes diabetic retinopathy via the regulation of integrin β1. The results of this study can provide a potential therapeutic application for the treatment of DR.

In-Depth Molecular Characterization of Neovascular Membranes Suggests a Role for Hyalocyte-to-Myofibroblast Transdifferentiation in Proliferative Diabetic Retinopathy

Background

Retinal neovascularization (RNV) membranes can lead to a tractional retinal detachment, the primary reason for severe vision loss in end-stage disease proliferative diabetic retinopathy (PDR). The aim of this study was to characterize the molecular, cellular and immunological features of RNV in order to unravel potential novel drug treatments for PDR.

Methods

A total of 43 patients undergoing vitrectomy for PDR, macular pucker or macular hole (control patients) were included in this study. The surgically removed RNV and epiretinal membranes were analyzed by RNA sequencing, single-cell based Imaging Mass Cytometry and conventional immunohistochemistry. Immune cells of the vitreous body, also known as hyalocytes, were isolated from patients with PDR by flow cytometry, cultivated and characterized by immunohistochemistry. A bioinformatical drug repurposing approach was applied in order to identify novel potential drug options for end-stage diabetic retinopathy disease.

Results

The in-depth transcriptional and single-cell protein analysis of diabetic RNV tissue samples revealed an accumulation of endothelial cells, macrophages and myofibroblasts as well as an abundance of secreted ECM proteins such as SPARC, FN1 and several types of collagen in RNV tissue. The immunohistochemical staining of cultivated vitreal hyalocytes from patients with PDR showed that hyalocytes express α-SMA (alpha-smooth muscle actin), a classic myofibroblast marker. According to our drug repurposing analysis, imatinib emerged as a potential immunomodulatory drug option for future treatment of PDR.

Conclusion

This study delivers the first in-depth transcriptional and single-cell proteomic characterization of RNV tissue samples. Our data suggest an important role of hyalocyte-to-myofibroblast transdifferentiation in the pathogenesis of diabetic vitreoretinal disease and their modulation as a novel possible clinical approach.

Mesenchymal stem cells induce tumor stroma formation and epithelial‑mesenchymal transition through SPARC expression in colorectal cancer

Tumor-stroma interactions serve a crucial role in the development of colorectal cancer (CRC), in which secreted protein acidic and rich in cysteine (SPARC) has been implicated. Due to interactions between cancer and stromal cells [mesenchymal stem cells (MSCs)], SPARC gene expression is markedly upregulated in CRC cells. The present study investigated the role of SPARC in CRC development and its potential as a biomarker. Specifically, the present study examined the association between SPARC expression and clinicopathological characteristics in 42 cases of CRC. SPARC expression in cancer cells was associated with T grade, N grade (TNM classification), stage and poor prognosis. Furthermore, the area of fibroblast-activating protein-positive staining around the cancer cells was increased in SPARC-positive compared with SPARC-negative cases. Proliferation and wound healing assays in SPARC-silenced KM12SM cells [short hairpin RNA SPARC (shSPARC)], the reduced SPARC expression of which was demonstrated by reverse transcription-quantitative PCR, revealed that the proliferative and migratory capacity of shSPARC cells did not differ from that of wild-type (WT) cells. However, it was markedly reduced when co-cultured with MSCs. Furthermore, in vivo, immunohistological analysis and RNA sequencing were conducted in an orthotopic implanted mouse model. Tumor growth and lymph node metastasis were markedly suppressed in shSPARC-transplanted tumors compared with WT-transplanted tumors, with a more marked suppression observed following shSPARC co-transplantation with MSCs. Immunohistological examination further revealed that the stromal reaction and epithelial-mesenchymal transition (EMT) were markedly suppressed in tumors co-transplanted with shSPARC and MSCs, and these results were consistent with RNA sequencing using RNA extracted from orthotopic tumors. Overall, these results suggested that SPARC expression in CRC cells is dependent on the interaction between cancer cells and stromal cells to induce EMT and promote stromal formation in the tumor microenvironment, suggesting its suitability as a novel target molecule for CRC treatment.

Risk stratification model based on VEGF and International Prognostic Index accurately identifies low-risk diffuse large B-cell lymphoma patients in the rituximab era

Vascular endothelial growth factor affects the invasiveness of solid tumors by regulating angiogenesis. However, it is not clear whether VEGF could be used to predict the prognosis of DLBCL in the era of rituximab-based immunotherapy. We conducted a retrospective study to explore response to therapy and the prognostic value of VEGF on DLBCL in the rituximab era. The subjects were 65 patients with a histological diagnosis of DLBCL from the Affiliated Hospital of Xuzhou Medical University. Kaplan-Meier analysis was performed to estimate the cumulative survival rate of patients with different VEGF and IPI levels, and comparisons between groups were made using the log-rank test. DLBCL patients with elevated VEGF were more likely to have extranodal involvement, advanced stage, Myc/Bcl-2 double expression, and a higher Ki-67 score. Elevated VEGF was associated with poor therapeutic response and survival. When patients were divided into low, low-intermediate, high-intermediate and high-risk groups using the V-IPI model based on VEGF and IPI, PFS rates were 94.4, 74.1, 40.6 and 14.8%, respectively. This model better identified low-risk patients than IPI (85.9, 88.9, 37 and 7.8%). Our results demonstrate that VEGF predicts therapeutic response in DLBCL and the V-IPI model accurately predicts PFS of low-risk DLBCL in the rituximab era.

SPARC promotes pancreatic cancer cell proliferation and migration through autocrine secretion into the extracellular milieu

SPARC is a secreted glycoprotein that plays a complex and multifaceted role in tumour formation and progression. However, whether SPARC is an oncogene or a tumour suppressor is still unclear. Moreover, SPARC demonstrates potential in clinical pancreatic adenocarcinoma (PAAD) treatment, although it has been identified as an oncogene in some studies and a tumor suppressor in others. In the present study, a pan-cancer analysis of SPARC was carried out using The Cancer genome Atlas data, which demonstrated that SPARC was an oncogene in most cancer types and a cancer suppressor in others. In addition, SPARC expression was significantly upregulated in PAAD and associated with poor prognosis. SPARC also promoted the proliferation and migration of PANC-1 and SW1990 cell lines in vitro. SPARC was detected in the culture supernatant of PAAD cells and pancreatic acinar AR42J cells. SPARC regulated PAAD cell proliferation only when secreted into the extracellular milieu, thus explaining why the prognosis of patients with PAAD is correlated with the SPARC expression of both tumour cells and stromal cells. Collectively, the present findings demonstrated that the function of SPARC was associated with tumour type and that SPARC may represent an important oncogene in PAAD that merits further study.

Low Levels of SPARC are Associated with Tumor Progression and Poor Prognosis in Human Endometrial Carcinoma

Background

SPARC (secreted protein acidic and rich in cysteine), also known as osteonectin, BM-40, and 43 K protein, is a matricellular protein associated with various tumor progressions. The aim of this research was to investigate the prognostic value of SPARC in endometrial carcinoma (EC) and its function in cancer cell invasion and metastasis.

Methods

From both mRNA and protein levels, SPARC expression in normal endometrial tissue and EC tissue, normal endometrial cells and 4 EC cell lines (KLE, HEC-1A, HEC-1B, Ishikawa) were evaluated by immunohistochemistry (IHC) or immunocytochemistry (ICC), quantitative real-time PCR (qRT-PCR) and Western blotting. RNA interference mediated by lentivirus was performed to get the stable SPARC down-expressing cells. The functional analysis techniques in vitro and in vivo were used to detect the effects of SPARC knockdown on EC cell proliferation, apoptosis, invasion and metastasis.

Results

The expressions of SPARC in EC tissues and cells were much lower than those in normal endometrial cells and tissues; meanwhile, its low expression was closely related to the malignant clinicopathological characteristics of EC. SPARC knockdown could inhibit apoptosis, promote the process of EMT and improve the proliferation and invasion capacities of EC cells in vitro and in vivo.

Conclusion

The low expression of SPARC was detected in EC tissues and cells, which was positively correlated with the poor prognosis of EC patients. SPARC acted as a tumor suppressor gene that hindered EC progression, which proposed a new therapeutic strategy for EC treatment.

VEGF Expression in Colorectal Cancer Metastatic Lymph Nodes: Clinicopathological Correlation and Prognostic Significance

Background: Angiogenesis plays an important role in colorectal cancer (CRC) tumorigenesis and metastatic progression. Methods: The present series consisted of CRC lymph node metastasis (LNM) tissue samples from 210 patients. Archival paraffin embedded LNM tissue were used to build up tissue microarray blocks and VEGF expression was immunohistochemically assessed. Results: VEGF-A and VEGF-C are overexpressed in LNM. VEGF-A was associated with patient age (p < 0.001), and VEGFR-2 and VEGFR-3 with CRC relapse (p = 0.032; p = 0.030, respectively). VEGF-C positivity was associated with VEGFR-3 positivity (p = 0.031), and VEGF-D with VEGFR-2 and VEGFR-3 (p ≤ 0.001). Matching the expression in LNM with CRC, in CRC VEGF-A positivity associates with VEGF-A, VEGF-C, VEGF-D, VEGF-R2, VEGF-R3 positivity in LNM; CRC VEGF-C with VEGF-D, VEGFR-2, VEGFR-3; CRC VEGFR-2 with VEGF-A, VEGF-C, VEGF-D, VEGFR-2, VEGFR-3; CRC VEGFR-3 with VEGF-A, VEGF-C, VEGF-D, VEGFR-2, VEGFR-3 in LNM. Conclusion: This study provides new information, revealing that VEGF family expression is increased in LNM. The association between the expression of VEGFR-2 and VEGFR-3 in LNM with CRC relapse reveals its impact on patient prognosis. Interesting data were found when the relationship between these proteins in primary tumor and their metastasis, were analyzed; VEGFA positivity in primary tumor is positively related to VEGF-A, VEGF-C, VEGF-D, VEGFR-2 and VEGFR-3 in their respective LNM suggesting mutual influence.

SPARC-p53: The double agents of cancer

Cancer is a complex disease with high incidence and mortality rates. The important role played by the tumor microenvironment in regulating oncogenesis, tumor growth, and metastasis is by now well accepted in the scientific community. SPARC is known to participate in tumor-stromal interactions and impact cancer growth in ambiguous ways, which either enhance or suppress cancer aggressiveness, in a context-dependent manner. p53 transcription factor, a well-established tumor suppressor, has been reported to promote tumor growth in certain situations, such as hypoxia, thus displaying a duality in its action. Although both proteins are being tested in clinical trials, the synergistic relation between them is yet to be explored in clinical practice. In this review, we address the controversial roles of SPARC and p53 as double agents in cancer, briefly summarizing the interaction found between these two molecules and its importance in cancer.

Prognostic role of secreted protein acidic and rich in cysteine in patients with solid tumors

OBJECTIVES

To analyze the heterogeneous functions of secreted protein acidic and rich in cysteine (SPARC) from different origins and in different tumor microenvironments with the purpose of determining its clinical significance. Methods: The PubMed, CINAHL, Cochrane, Web of Science and Embase databases were utilized. Studies that focused on the effects of SPARC expression on solid tumor progression and clinical implications were used. The different outcomes including overall survival and disease-free survival were analyzed to evaluate their relations with tumor- and stroma-derived SPARC expression. Results: A total of 26 studies including 5,939 patients were enrolled in the present meta-analysis. Tumor-derived SPARC overexpression was significantly related with poor overall survival (hazard ratio: 1.478; 95% CI: 1.143-1.910; p=0.003), and a similar tendency was also observed in disease-free survival (hazard ratio: 1.476; 95% CI: 0.993-2.195; p=0.054). However, the hazard ratios for overall survival and disease-free survival did not present a statistical trend in stromal SPARC overexpression. Tumor type subgroup analysis revealed marked heterogeneity among outcomes. In pancreatic cancer, SPARC overexpression in the stroma was significantly associated with poorer overall survival and disease-free survival. In colorectal cancer, SPARC overexpression in the stroma was associated with better disease-free survival. Conclusion: For the majority of solid tumors, SPARC in cancer cells may be an unfavorable indicator for long-term survival for patients. As for stromal expression, SPARC indicates a poorer prognosis in pancreatic cancer, but a better disease-free survival in colorectal cancer. Secreted protein acidic and rich in cysteine might be a potential biomarker for solid tumor prognosis.

LINC00261 suppresses human colon cancer progression via sponging miR-324-3p and inactivating the Wnt/β-catenin pathway

Growing evidence indicates long noncoding RNAs (lncRNAs) are significant regulators in the progression of various malignant tumors including colon cancer. Dysregulation of lncRNA LINC00261 has been identified in many cancers. Investigations on LINC00261 function have revealed that LINC00261 could act as a crucial tumor suppressor in various cancers. But, the biological involvement of LINC00261 in colon cancer is still barely known. Here, we found LINC00261 was reduced in colon cancer cells. Meanwhile, overexpressed LINC00261 repressed colon cancer cell viability and proliferation capacity. In addition, colony cancer cell colony formation was inhibited and apoptosis was enhanced by upregulation of LINC00261. Also, colon cancer cell migration and invasion both were restrained by LINC00261. miR-324-3p can exert important functions in several carcinomas, but its role in colon cancer is uninvestigated. In the current study, miR-324-3p was examined and miR-324-3p was greatly increased in colon cancer cells. Moreover, the association between miR-324-3p and LINC00261 was confirmed via performing RNA immunoprecipitation and RNA-pull-down experiments. In cancer biology, aberrant modulation of the Wnt signaling pathway remains a prevalent theme. Overexpression of LINC00261 obviously impaired colon cancer progression via inactivating the Wnt pathway. Furthermore, in the xenograft model assay, an increase of LINC00261 could suppress colon tumor growth via sponging miR-324-3p and inactivating the Wnt pathway. Overall, our results showed that LINC00261 repressed colon cancer progression via regulating miR-324-3p and the Wnt pathway. LINC00261 could be established as a novel therapeutic target for colon cancer.

Downregulation of SPARC Is Associated with Epithelial-Mesenchymal Transition and Low Differentiation State of Biliary Tract Cancer Cells

BACKGROUND

Biliary tract cancers (BTCs) have a poor prognosis. BTCs are characterized by a prominent desmoplastic reaction which possibly contributes to the aggressive phenotype of this tumor. The desmoplastic reaction includes excessive production and deposition of extracellular matrix proteins such as periostin, secreted protein acidic and rich in cysteine (SPARC), thrombospondin-1, as well as accumulation of α-smooth muscle actin-positive cancer-associated fibroblasts and immune cells, secreting growth factors and cytokines including transforming growth factor (TGF)-β. In the present study, we investigated the expression of SPARC in BTC as well as its possible regulation by TGF-β.

METHODS

Expression levels of Sparc, TGF-β1 and its receptor ALK5 were evaluated by quantitative real-time PCR in 6 biliary tract cell lines as well as 1 immortalized cholangiocyte cell line (MMNK-1). RNAs from tumor samples of 7 biliary tract cancer patients were analyzed for expression of Sparc, TGF-β type II receptor (TbRII) as well as Twist and ZO-1. MMNK-1 cells were stimulated with TGF-β for 24 h, and Sparc, ZO-1 and E-Cadherin expressions were determined. The presence of SPARC protein was analyzed by immunohistochemistry in tumor specimens from 10 patients.

RESULTS

When comparing basal Sparc transcript levels in diverse BTC cell lines to MMNK-1 cells, we found that it was strongly downregulated in all cancer cell lines. The remaining expression levels were higher in highly differentiated cell lines (CCSW1, MZChA1, MZChA2 and TFK-1) than in less differentiated and undifferentiated ones (BDC, SKChA1). Expression of Sparc in BTC patient samples showed a significant positive correlation with expression of the epithelial marker ZO-1. In contrast, the mesenchymal marker Twist and the TbRII showed a trend of negative correlation with expression of Sparc in these samples. TGF-β exposure significantly downregulated Sparc expression in MMNK-1 cholangiocytes in vitro in parallel to downregulation of epithelial markers (E-Cadherin and ZO-1). Finally, SPARC immunostaining was performed in 10 patient samples, and the correlation between absence of SPARC and survival times was analyzed.

CONCLUSIONS

These data imply that a decrease in SPARC expression is correlated with dedifferentiation of BTC cells resulting in enhanced EMT being possibly mediated by TGF-β. Thereby SPARC levels might be a marker for individual prognosis of a patient, and strategies aiming at inhibition of SPARC downregulation might have potential for new future therapies.

Evaluation of the Biological Behavior of a Gold Nanocore-Encapsulated Human Serum Albumin Nanoparticle (Au@HSANP) in a CT-26 Tumor/Ascites Mouse Model after Intravenous/Intraperitoneal Administration

Colorectal cancer is one of the major causes of cancer-related death in Taiwan and worldwide. Patients with peritoneal metastasis from colorectal cancer have reduced overall survival and poor prognosis. Hybrid protein-inorganic nanoparticle systems have displayed multifunctional applications in solid cancer theranostics. In this study, a gold nanocore-encapsulated human serum albumin nanoparticle (Au@HSANP), which is a hybrid protein-inorganic nanoparticle, and its radioactive surrogate ¹¹¹In-labeled Au@HSANP (¹¹¹In-Au@HSANP), were developed and their biological behaviors were investigated in a tumor/ascites mouse model. ¹¹¹In-Au@HSANP was injected either intravenously (iv) or intraperitoneally (ip) in CT-26 tumor/ascites-bearing mice. After ip injection, a remarkable and sustained radioactivity retention in the abdomen was noticed, based on microSPECT images. After iv injection, however, most of the radioactivity was accumulated in the mononuclear phagocyte system. The results of biodistribution indicated that ip administration was significantly more effective in increasing intraperitoneal concentration and tumor accumulation than iv administration. The ratios of area under the curve (AUC) of the ascites and tumors in the ip-injected group to those in the iv-injected group was 93 and 20, respectively. This study demonstrated that the ip injection route would be a better approach than iv injections for applying gold-albumin nanoparticle in peritoneal metastasis treatment.

Bioinformatics Analysis Reveals Most Prominent Gene Candidates to Distinguish Colorectal Adenoma from Adenocarcinoma

Colorectal cancer (CRC) is one of the leading causes of death by cancer worldwide. Bowel cancer screening programs enable us to detect early lesions and improve the prognosis of patients with CRC. However, they also generate a significant number of problematic polyps, e.g., adenomas with epithelial misplacement (pseudoinvasion) which can mimic early adenocarcinoma. Therefore, biomarkers that would enable us to distinguish between adenoma with epithelial misplacement (pseudoinvasion) and adenoma with early adenocarcinomas (true invasion) are needed. We hypothesized that the former are genetically similar to adenoma and the latter to adenocarcinoma and we used bioinformatics approach to search for candidate genes that might be potentially used to distinguish between the two lesions. We used publicly available data from Gene Expression Omnibus database and we analyzed gene expression profiles of 252 samples of normal mucosa, colorectal adenoma, and carcinoma. In total, we analyzed 122 colorectal adenomas, 59 colorectal carcinomas, and 62 normal mucosa samples. We have identified 16 genes with differential expression in carcinoma compared to adenoma: COL12A1, COL1A2, COL3A1, DCN, PLAU, SPARC, SPON2, SPP1, SULF1, FADS1, G0S2, EPHA4, KIAA1324, L1TD1, PCKS1, and C11orf96. In conclusion, our in silico analysis revealed 16 candidate genes with different expression patterns in adenoma compared to carcinoma, which might be used to discriminate between these two lesions.

Angiodrastic Chemokines in Colorectal Cancer: Clinicopathological Correlations

Aim

To study the expression of angiodrastic chemokines in colorectal tumors and correlate findings with clinicopathological parameters and survival.

Methods

The proangiogenic factor VEGF, the angiogenic chemokines CXCL8 and CXCL6, and the angiostatic chemokine CXCL4 were measured by ELISA in tumor and normal tissue of 35 stage II and III patients and correlated with the histopathology markers Ki67, p53, p21, bcl2, EGFR, and MLH1 and 5-year survival. The Wilcoxon and chi-square tests were used for statistical comparisons.

Results

There was a significant increase of CXCL6 (p = 0.005) and VEGF (p = 0.003) in cancerous tissue compared to normal. Patients with lower levels of CXCL8 and CXCL4 lived significantly longer. Patients with loss of EGFR expression had higher levels of CXCL8 while p21 loss was associated with higher levels of CXCL6. Chemokine levels were not correlated with TNM or Dukes classification. Strong expression of p53 was accompanied by decreased survival.

Conclusions

(1) The angiogenic factors CXCL6 and VEGF are increased in colorectal cancer tissue with no association with the clinical stage of the disease or survival. (2) However, increased levels of tissue CXCL8 and CXCL4 are associated with poor survival. (3) Strong expression of p53 is found in patients with poor survival.

LncRNA MALAT1 induces colon cancer development by regulating miR-129-5p/HMGB1 axis

Recent studies have exhibited significant roles of lncRNAs in various tumors' development, including colon cancer. Our study focused on the biological roles of lncRNA MALAT1 in colon cancer. In our study, it was demonstrated that MALAT1 was upregulated in human colon cancer cell lines including Lovo, HCT116, SW480, and HT29 cells compared to the normal human intestinal epithelial HIEC cells. Moreover, we observed that miR-129-5p was downregulated in colon cancer cells with a significant increase of HMGB1 expression. Inhibition of MALAT1 can inhibit the proliferation of colon cancer SW480 and HCT116 cells and next, bioinformatics analysis was used to predict the target microRNA of MALAT1. miR-129-5p was identified and confirmed as a direct regulator of MALAT1 and it was shown that miR-129-5p mimics were able to restrain the progression of colon cancer cells. In addition, high motility group box protein 1 (HMGB1), was predicted as a mRNA target of miR-129-5p. Furthermore, we found that MALAT1 exerted its biological functions through regulating HMGB1 by sponging miR-129-5p in vitro. Silencing MALAT1 greatly inhibited HMGB1 expression which can be reversed by miR-129-5p inhibitors. It was indicated in our investigation that MALAT1 may serve as a competing endogenous lncRNA (ceRNA) to mediate HMGB1 by sponging miR-129-5p in colon cancer. Taken together, our results indicated that MALAT1/miR-129-5p/HMGB1 axis could be provided as an important prognostic biomarker in colon cancer development.

SPARC: As a prognostic biomarker in rectal cancer patients treated with chemo-radiotherapy

BACKGROUND

The aim of this study is to search the prognostic value of SPARC expression in rectum cancer cases receiving postoperative radiotherapy.

METHODS

Forty three rectal cancer patients are recruited to this retrospective study. All patients received postoperative radiotherapy which the median dose was 5040 cGy and concomitant chemotherapy. Samples taken from their paraffin blocks were examined with immunohistochemical procedures.

RESULTS

When the association between SPARC expression and the clinicopathological feature was examined, there was a significant association between age and expression levels. Overall survival of patients with low expression was found to be 67 months whereas the overall survival of the patients with high expression was 32 months and the difference was statistically significant. Time to local recurrence of patients with low expression was found to be 74 months whereas time to local recurrence of the patients with high expression was 31 months. Progression free survival of the patients with low expression and high expression were 67 months and 32 months, respectively. In multivariate Cox regression analyses, high expression of SPARC was found to be associated with a statistically significant shorter overall survival and progression free survival.

CONCLUSIONS

High expression of SPARC is related to worse prognosis in rectal cancer patients.

Matricellular proteins and survival in patients with pancreatic cancer: A systematic review

Extracellular matrix (ECM) plays a fundamental role in tissue architecture and homeostasis and modulates cell functions through a complex interaction between cell surface receptors, hormones, several bioeffector molecules, and structural proteins like collagen. These components are secreted into ECM and all together contribute to regulate several cellular activities including differentiation, apoptosis, proliferation, and migration. The so-called "matricellular" proteins (MPs) have recently emerged as important regulators of ECM functions. The aim of our review is to consider all different types of MPs family assessing the potential relationship between MPs and survival in patients with pancreatic ductal adenocarcinoma (PDAC). A systematic computer-based search of published articles, according to the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) Statement issued in 2009 was conducted through Ovid interface, and literature review was performed in May 2017. The search text words were identified by means of controlled vocabulary, such as the National Library of Medicine's MESH (Medical Subject Headings) and Keywords. Collected data showed an important role of MPs in carcinogenesis and in PDAC prognosis even though the underlying mechanisms are still largely unknown and data are not univocal. Therefore, a better understanding of MPs role in regulation of ECM homeostasis and remodeling of specific organ niches may suggest potential novel extracellular targets for the development of efficacious therapeutic strategies.

A novel role for OATP2A1/SLCO2A1 in a murine model of colon cancer

Prostaglandin E₂ (PGE₂) is associated with proliferation and angiogenesis in colorectal tumours. The role of prostaglandin transporter OATP2A1/SLCO2A1 in colon cancer tumorogenesis is unknown. We evaluated mice of various Slco2a1 genotypes in a murine model of colon cancer, the adenomatous polyposis (APC) mutant (Apc^∆716/+) model. Median lifespan was significantly extended from 19 weeks in Slco2a1^+/+/Apc^Δ716/+ mice to 25 weeks in Slco2a1^−/−/Apc^Δ716/+ mice. Survival was directly related to a reduction in the number of large polyps in the Slco2a1^−/−/Apc^∆716/+ compared to the Slco2a1^+/+/Apc^Δ716/+ or Slco2a1^+/−/Apc^Δ716/+mice. The large polyps from the Slco2a1^−/−/Apc^∆716/+ mice had significant reductions in microvascular density, consistent with the high expression of Slco2a1 in the tumour-associated vascular endothelial cells. Chemical suppression of OATP2A1 function significantly reduced tube formation and wound-healing activity of PGE₂ in human vascular endothelial cells (HUVECs) although the amount of extracellular PGE₂ was not affected by an OATP2A1 inhibitor. Further an in vivo model of angiogenesis, showed a significant reduction of haemoglobin content (54.2%) in sponges implanted into Slco2a1^−/−, compared to wildtype mice. These studies indicate that OATP2A1 is likely to promote tumorogenesis by PGE₂ uptake into the endothelial cells, suggesting that blockade of OATP2A1 is an additional pharmacologic strategy to improve colon cancer outcomes.

SPARC suppresses lymph node metastasis by regulating the expression of VEGFs in ovarian carcinoma

Lymph node metastasis is one of the most valuable determinants for the prognosis of ovarian cancer. However, the molecular mechanisms underlying lymphangiogenesis in ovarian cancer is still poorly understood. Secreted protein acidic and rich in cysteine (SPARC), a Ca2+-binding matricellular glycoprotein that modulates cell adhesion, migration and differentiation, is thought to play a decisive role in tumor metastasis. Vascular endothelial growth factor (VEGF)-C and VEGF-D contributes to tumor-associated lymphatic vessel growth, enhancing the metastatic spread of tumor cells to lymph nodes. The aim of the present study was to investigate the relationship among SPARC, VEGFs and lymph node metastasis in ovarian cancer. We found that SKOV3 cells expressed high-level SPARC, much more than SKOV3-PM4 cells (a subline with high directional lymphatic metastatic potentials established from the metastatic lymph node generated by human ovarian carcinoma cell line SKOV3 in nude mice) did at both mRNA and protein levels. A SPARC-overexpressed SKOV3-PM4 cell line was constructed and it was found that upregulation of SPARC expression suppressed the growth, migration and invasion of SKOV3-PM4 cells as well as markedly reduced the expression of VEGF-D at both mRNA and protein level by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assay. In 47 of ovarian malignant tissues, the expression of SPARC, VEGF-C and VEGF-D were determined by immunohistochemistry. Lymphatic microvessel density (LVD) and microvessel density (MVD) were evaluated by immunostaining with CD34 and D2-40 antibodies, respectively. We found that SPARC expression was significantly lower in tissues with lymph node metastasis as compared to tissues without lymph node metastasis. SPARC expression was inversely associated with the degree of malignancy and it had a negative correlation with VEGF-C expression, VEGF-D expression, LVD and MVD which were actually higher for advanced tumors than for non-advanced tumors. These results suggest SPARC might function as a tumor suppressor inhibiting angiogenesis and lymphangiogenesis in ovarian cancer by reducing the expression of VEGF-C and VEGF-D.

The relationship between stromal cell derived SPARC in human gastric cancer tissue and its clinicopathologic significance

Background

We aimed to investigate the cellular source of secreted protein acidic and rich in cysteine (SPARC) in gastric cancer tissues and the relationship between SPARC expression and its prognostic significance.

Methods

The expression of SPARC in 365 primary advanced gastric adenocarcinomas and 39 non-cancerous tissues was evaluated by immunohistochemical staining. Double-immunofluorescence staining was used to reveal the cellular source of SPARC in tumor tissues. Western blotting and immunofluorescence staining were applied for verifying the endogenous expression of SPARC in human cell lines of gastric cancer and fibroblast.

Results

Higher positivity of SPARC was observed in gastric cancer tissues than non-cancerous gastric tissues (P=0.000). The positivity of SPARC was related to age (P=0.032), tumor location (P=0.018), depth of tumor invasion (P=0.011), nodal metastasis (P=0.023), TNM stage (P=0.034), the differentiation degree (P=0.006) and pathological type (P=0.002) of gastric cancer. SPARC in gastric cancer tissues was mainly expressed by cancer-associated fibroblasts. SPARC also appeared in neovascular endothelial cells and a few tumor-associated macrophages. The endogenous expression of SPARC in fibroblasts was suppressed by mucus-producing gastric adenocarcinoma cells(MKN-45). Increased SPARC expression in gastric cancer tissue was suggestive of a shorter cumulative survival in the patients with gastric adenocarcinoma, though this difference was not statistically significant(P>0.05).

Conclusion

SPARC in human gastric cancer tissue was derived from the stromal cells and was mainly produced by cancer-associated fibroblasts. Production of SPARC in fibroblasts was reduced by the mucus-producing gastric adenocarcinoma cells.

Colon cancer recurrence‑associated genes revealed by WGCNA co‑expression network analysis

The present study aimed to identify the recurrence-associated genes in colon cancer, which may provide theoretical evidence for the development of novel methods to prevent tumor recurrence. Colon cancer and matched normal samples microarray data (E-GEOD-39582) were downloaded from ArrayExpress. Genes with significant variation were identified, followed by the screening of differentially expressed genes (DEGs). Subsequently, the co-expression network of DEGs was constructed using the weighted correlation network analysis (WGCNA) method, which was verified using the validation dataset. The significant modules associated with recurrence in the network were subsequently screened and verified in another independent dataset E-GEOD-33113. Function and pathway enrichment analyses were also conducted to determine the roles of selected genes. Survival analysis was performed to identify the association between these genes and survival. A total of 434 DEGs were identified in the colon samples, and stress-associated endoplasmic reticulum protein family member 2 (SERP2) and long non-coding RNA-0219 (LINC0219) were determined to be the vital DEGs between all the three sub-type groups with different clinical features. The brown module was identified to be the most significant module in the co-expression network associated with the recurrence of colon cancer, which was verified in the E-GEOD-33113 dataset. Top 10 genes in the brown module, including EGF containing fibulin like extracellular matrix protein 2 (EFEMP2), fibrillin 1 (FBN1) and secreted protein acidic and cysteine rich (SPARC) were also associated with survival time of colon cancer patients. Further analysis revealed that the function of cell adhesion, biological adhesion, extracellular matrix (ECM) organization, pathways of ECM-receptor interaction and focal adhesion were the significantly changed terms in colon cancer. In conclusion, SERP2, EFEMP2, FBN1, SPARC, and LINC0219 were revealed to be the recurrence-associated molecular and prognostic indicators in colon cancer by WGCNA co-expression network analysis.

Epigenetic effects of inhibition of heat shock protein 90 (HSP90) in human pancreatic and colon cancer

Silencing of tumor suppressor and DNA repair genes through methylation plays a role in cancer development, growth and response to therapy in colorectal and pancreatic cancers. Heat shock protein 90 (HSP90) regulates transcription of DNA methyltransferase enzymes (DNMT). In addition, DNMTs are client proteins of HSP90. The aim of this study is to evaluate the effects of HSP90 inhibition on DNA methylation in colorectal and pancreatic cancer cell lines. Our data shows that inhibition of HSP90 using ganetespib resulted in downregulation of mRNA and protein expression of DNMT1, DNMT3A, and DNMT3B in HT-29 and MIA PaCa-2 cell lines. This in turn was associated with a drop in the fraction of methylated cytosine residues and re-expression of silenced genes including MLH-1, P16 and SPARC. These effects were validated in HT-29 tumors implanted subcutaneously in mice following in vivo administration of ganetespib. This work demonstrates the effectiveness of ganetespib, an HSP90 inhibitor in modulating DNA methylation through downregulation of DNMT expression.

Self-Targeting, Immune Transparent Plasma Protein Coated Nanocomplex for Noninvasive Photothermal Anticancer Therapy

Cancer cells exhibit specific physiological differences compared to normal cells. Most surface membranes of cancer cells are characterized by high expression of given protein receptors, such as albumin, transferrin, and growth factors that are also present in the plasma of patients themselves, but are lacking on the surface of normal cells. These distinct features between cancer and normal cells can serve as a niche for developing specific treatment strategies. Near-infrared (NIR)-light-triggered therapy platforms are an interesting novel avenue for use in clinical nanomedicine. As a photothermal agent, conducting polymer nanoparticles, such as polypyrrole (PPy), of great NIR light photothermal effects and good biocompatibility, show promising applications in cancer treatments through the hyperthermia mechanism. Autologous plasma proteins coated PPy nanoparticles for hyperthermia therapy as a novel core technology platform to treat cancers through secreted protein acid and rich in cysteine targeting are developed here. This approach can provide unique features of specific targeting toward cancer cell surface markers and immune transparency to avoid recognition and attack by defense cells and achieve prolonged circulation half-life. This technology platform unveils new clinical options for treatment of cancer patients, supporting the emergence of innovative clinical products.

Supervised Clustering of Adipokines and Hormonal Receptors Predict Prognosis in a Population of Obese Women with Type 1 Endometrial Cancer

Obesity is a major risk factor for endometrial cancer (EC). Yet, its impact on prognosis is controversial. Obesity is associated with metabolic and hormonal dysregulation as well as adipokines increase. The aim of this study was to characterize the expression of biological factors related to obesity within the tumor and evaluate their impact on prognosis. One hundred and thirty-six patients, including 55 obese patients, with endometrioid type I EC operated by total hysterectomy were included in this retrospective study conducted in a Tertiary teaching hospital between 2000 and 2013. Immunohistochemistry (IHC) study was performed on type I EC tumor samples using five adipokines (SPARC, RBP4 (Retinol Binding Protein 4), adiponectin, TNF α, IL-6) and hormonal receptors (estrogen receptor and progesterone receptor). Supervised clustering of immunohistochemical markers was performed to identify clusters that could be associated with prognostic groups. The prognosis of the obese population was not different from the prognosis of the general population. Adipokine expression within tumors was not different in these two populations. In obese population, we found three clusters where co-expression was associated with a recurrence group in comparison with a non-recurrence group and four clusters where co-expression was associated with the high risk FIGO (International Federation of Gynecology and Obstetrics) stage I group in comparison of low risk FIGO stage I group. While obesity does not appear as a prognostic factor in endometrioid type I EC, the co-expression of biological factors in IHC on hysterectomy specimens allowed to distinguish two prognostic groups in obese population.

Novel Palladium(II) Complexes that Influence Prominin-1/CD133 Expression and Stem Cell Factor Release in Tumor Cells

New Pd(II) complexes of 1,7-bis(2-methoxyphenyl)hepta-1,6-diene-3,5-dione were synthesized and structurally characterized. The complexes were tested in vitro on human colon and hepatic carcinoma cell lines, normal hepatic cells and hematopoietic progenitor cells. Biological tests proved that Pd(II) complexes 1 and 2 (containing a curcumin derivative) exhibit a strong in vitro antitumor effect against the cells derived from human colorectal carcinoma and the hepatic metastasis of a colorectal carcinoma. Complex 1 has an outstanding inhibitory effect against BRAF-mutant colon carcinoma and hepatocarcinoma cell growth; 1 and 2 are both more active than the free ligand and have the capacity to trigger early apoptotic processes. By flow cytometric measurements, an important decrease of prominin-1 (CD133) molecule expression on tumor cells membrane was identified in cell populations subjected to 1 and 2. Quantitative immune enzymatic assay proved restrictions in stem cell factor (SCF) release by treated tumor cells. Although less cytotoxic, the free ligand inhibits the surface marker CD133 expression in hepatocarcinoma cells, and in HT-29 colon carcinoma. The new synthesized Pd(II) complexes 1 and 2 exhibit an important potential through their selective cytotoxic activity and by targeting the stem-like tumor cell populations, which leads to the tumor growth arrest and prevention of metastasis.

Cell Competition During Growth and Regeneration

Tissue growth and regeneration are autonomous, stem-cell-mediated processes in which stem cells within the organ self-renew and differentiate to create new cells, leading to new tissue. The processes of growth and regeneration require communication and interplay between neighboring cells. In particular, cell competition, which is a process in which viable cells are actively eliminated by more competitive cells, has been increasingly implicated to play an important role. Here, we discuss the existing literature regarding the current landscape of cell competition, including classical pathways and models, fitness fingerprint mechanisms, and immune system mechanisms of cell competition. We further discuss the clinical relevance of cell competition in the physiological processes of tissue growth and regeneration, highlighting studies in clinically important disease models, including oncological, neurological, and cardiovascular diseases.

Extracellular matrix gene expression profiling using microfluidics for colorectal carcinoma stratification

In cancer, biomarkers have many potential applications including generation of a differential diagnosis, prediction of response to treatment, and monitoring disease progression. Many molecular biomarkers have been put forward for different diseases but most of them do not possess the required specificity and sensitivity. A biomarker with a high sensitivity has a low specificity and vice versa. The inaccuracy of the biomarkers currently in use has led to a compelling need to identify more accurate markers with diagnostic and prognostic significance. The aim of the present study was to use a novel, droplet-based, microfluidic platform to evaluate the prognostic value of a panel of thirty-four genes that regulate the composition of extracellular matrices in colorectal carcinoma. Our method is a novel approach as it uses using continuous-flowing Polymerase Chain Reaction for the sensitive detection and accurate quantitation of gene expression. We identified a panel of relevant extracellular matrix genes whose expression levels were measured by real-time quantitative polymerase chain reaction using Taqman^® reagents in twenty-four pairs of matched colorectal cancer tumour and associated normal tissue. Differential expression patterns occurred between the normal and malignant tissue and correlated with histopathological parameters and overall surgical staging. The findings demonstrate that a droplet-based microfluidic quantitative PCR system enables biomarker classification. It was further possible to sub-classify colorectal cancer based on extracellular matrix protein expressing groups which in turn correlated with prognosis.

Predictive Significance of VEGF and HIF-1α Expression in Patients with Metastatic Colorectal Cancer Receiving Chemotherapy Combinations with Bevacizumab

BACKGROUND

There is no suggested molecular indicator for the determination of which patients will benefit from anti-angiogenetic treatment in metastatic colorectal cancers.

MATERIALS AND METHODS

In this study, VEGF and HIF-1α expression and their clinical significance were studied in tumor tissues of patients with colorectal cancer receiving bevacizumab-based treatment. VEGF and HIF-1α were assessed by immunohistochemistry in the primary tumors of 53 metastatic colorectal cancer patients receiving chemotherapy in combination with first line bevacizumab.

RESULTS

The clinical benefit rate in the low-VEGF expression group was 38%, while it was 62% in the high expression group. While the median progression-free survival (PFS) was 10 months in the high-VEGF expression group, it was 8 months in the low-VEGF expression group (p = 0.009). The median overall survival (OS) was found to be 26 months vs 15 months. Thus, when VEGF was strongly expressed it was in favor of that group and the difference was statistically significant (p = 0.03). High VEGF expression rate was an independent factor that correlated with OS or PFS (p=0.016 and 0.009, respectively).

CONCLUSIONS

The data showed that VEGF may have predictive value for determining the treatment of CRC.

Exenatide suppresses 1,2-dimethylhydrazine-induced colon cancer in diabetic mice: Effect on tumor angiogenesis and cell proliferation

Colon cancer is the third leading cause of cancer mortality worldwide, which results from interactions of different factors. It is frequently a pathological consequence of persistent inflammation. Diabetes affects several cancers and is positively correlated with the incidence of colon cancer. This study aimed to study the effect of exenatide in ameliorating inflammation, angiogenesis and cell proliferation in 1,2-dimethyl hydrazine (DMH) induced colorectal carcinoma in diabetic mice. Mice were randomly allocated into six groups, 8 mice each. Group 1: vehicle control group. Group 2: diabetic control group. Group 3: DMH control group: diabetic mice treated with DMH (20mg/kg/week,s.c.) for 15 week. Group 4: DMH-cisplatin group: mice received cisplatin (4mg/kg/week, i.p.). Groups 5 & 6: DMH-exenatide (10 and 20μg/kg) group: mice received exenatide (10 or 20μg/kg/day,s.c.), respectively. The present results highlighted an increase in angiogenic markers and cell proliferation in the DMH-diabetic group in comparison with the control group with greater expression of endothelial marker (CD34) and Ki-67 in colon tissue. Monotherapy with cisplatin or exenatide (10 and 20μg/kg) downregulated these markers to different extents. The current results provided evidence that exenatide represents a promising chemopreventive effect against DMH-induced colon carcinogenesis in diabetic mice, at least in part, attributed to its anti-angiogenic and anti-proliferative mechanisms.

SPARC Expression Is Selectively Suppressed in Tumor Initiating Urospheres Isolated from As+3- and Cd+2-Transformed Human Urothelial Cells (UROtsa) Stably Transfected with SPARC

BACKGROUND

This laboratory previously analyzed the expression of SPARC in the parental UROtsa cells, their arsenite (As(+3)) and cadmium (Cd(+2))-transformed cell lines, and tumor transplants generated from the transformed cells. It was demonstrated that SPARC expression was down-regulated to background levels in Cd(+2)-and As(+3)-transformed UROtsa cells and tumor transplants compared to parental cells. In the present study, the transformed cell lines were stably transfected with a SPARC expression vector to determine the effect of SPARC expression on the ability of the cells to form tumors in immune-compromised mice.

METHODS

Real time PCR, western blotting, immunohistochemistry, and immunofluorescence were used to define the expression of SPARC in the As(+3)-and Cd(+2)-transformed cell lines, and urospheres isolated from these cell lines, following their stable transfection with an expression vector containing the SPARC open reading frame (ORF). Transplantation of the cultured cells into immune-compromised mice by subcutaneous injection was used to assess the effect of SPARC expression on tumors generated from the above cell lines and urospheres.

RESULTS

It was shown that the As(+3)-and Cd(+2)-transformed UROtsa cells could undergo stable transfection with a SPARC expression vector and that the transfected cells expressed both SPARC mRNA and secreted protein. Tumors formed from these SPARC-transfected cells were shown to have no expression of SPARC. Urospheres isolated from cultures of the SPARC-transfected As(+3)-and Cd(+2)-transformed cell lines were shown to have only background expression of SPARC. Urospheres from both the non-transfected and SPARC-transfected cell lines were tumorigenic and thus fit the definition for a population of tumor initiating cells.

CONCLUSIONS

Tumor initiating cells isolated from SPARC-transfected As(+3)-and Cd(+2)-transformed cell lines have an inherent mechanism to suppress the expression of SPARC mRNA.

Reprogramming energy metabolism and inducing angiogenesis: co-expression of monocarboxylate transporters with VEGF family members in cervical adenocarcinomas

Background

Deregulation of cellular energetic metabolism was recently pointed out as a hallmark of cancer cells. This deregulation involves a metabolic reprogramming that leads to a high production of lactate. Lactate efflux, besides contributing for the glycolytic flux, also acts in the extracellular matrix, contributing for cancer malignancy, by, among other effects, induction of angiogenesis. However, studies on the interplay between cancer metabolism and angiogenesis are scarce. Therefore, the aim of the present study was to evaluate the metabolic and vascular molecular profiles of cervical adenocarcinomas, their co-expression, and their relation to the clinical and pathological behavior.

Methods

The immunohistochemical expression of metabolism-related proteins (MCT1, MCT4, CD147, GLUT1 and CAIX) as well as VEGF family members (VEGF-A, VEGF-C, VEGF-D, VEGFR-1, VEGFR-2 and VEGFR-3) was assessed in a series of 232 cervical adenocarcinomas. The co-expression among proteins was assessed and the expression profiles were associated with patients’ clinicopathological parameters.

Results

Among the metabolism-related proteins, MCT4 and CAIX were the most frequently expressed in cervical adenocarcinomas while CD147 was the less frequently expressed protein. Overall, VEGF family members showed a strong and extended expression with VEGF-C and VEGFR-2 as the most frequently expressed and VEGFR-1 as the less expressed member. Co-expression of MCT isoforms with VEGF family members was demonstrated. Finally, MCT4 was associated with parametrial invasion and HPV18 infection, CD147 and GLUT1 with distant metastasis, CAIX with tumor size and HPV18 infection, and VEGFR-1 with local and lymphnode metastasis.

Conclusions

The results herein presented provide additional evidence for a crosstalk between deregulating cellular energetics and inducing angiogenesis. Also, the metabolic remodeling and angiogenic switch are relevant to cancer progression and aggressiveness in adenocarcinomas.

Comparison of (18)F-fluorodeoxyglucose PET/CT findings with vascular endothelial growth factors and receptors in colorectal cancer

The purpose of this study was to evaluate the association of (18)F-fluorodeoxyglucose (FDG)-PET/CT findings with the vascular endothelial growth factor (VEGF) family and its receptor (VEGFR) levels in metastatic and nonmetastatic colorectal cancer (CRC). Fluorine-18 FDG-PET/CT scans were performed for initial staging and restaging of patients with CRC. FDG-PET/CT findings of tumor (such as the presence of a primary tumor, the lymphatic or distance metastases, and the maximum standardized uptake value (SUVmax) of the primary tumor), serum VEGF A-C-D-E levels, and serum VEGF receptor 1-2-3 levels were analyzed. A total of 63 patients were included into the study (35 males, mean age 61.3 ± 11.9 years). Patients were divided into two groups, based on positive and negative PET/CT findings. Patients were also categorized according to the presence of metastasis. All evaluated parameters were significantly higher in the PET/CT-positive group than the PET/CT-negative group (p < 0.001). All those parameters were also positively correlated with each other. The highest correlation for SUVmax of primary tumor was found with VEGFR-3 (p < 0.001, r = 0.665). Patients with metastases had high levels of VEGF-D, VEGF-A, VEGF-C, VEGF-E, and VEGFR-3 than those without metastases. These parameters had better specificity and sensitivity values than the SUVmax of the primary tumor for detection of metastases. However, VEGF-D was the best indicator of metastasis in all of those parameters (VEGF-D vs SUVmax; sensitivity 100 vs 100 %; specificity 76 vs 76 %; AUC 0.903 vs 0.835; p < 0.001, respectively). Vascular endothelial growth factor family and its receptors were significantly higher in metastatic CRC patients. VEGF-D was the best indicator of metastasis than all VEGF family, VEGFR-3, and primary tumor SUVmax. VEGF family (A-C-D-E) and VEGFR-3 may help to determine the prognosis and management of CRC.

Deletion of SPARC Enhances Retinal Vaso-Obliteration in Mouse Model of Oxygen-Induced Retinopathy

BACKGROUND

Secreted Protein Acidic and Rich in Cysteine (SPARC) is a matricellular protein which is implicated in regulation of angiogenesis.

PURPOSE

To characterize the changes in SPARC expression and effect of its deletion in a mouse model Oxygen Induced Retinopathy (OIR).

MATERIALS AND METHODS

Wild type (wt) and SPARC-deficient mice were subjected to high oxygen (75%) for 5 days (p7-p12) before room air for additional 5 days (p12-p17). Retinas from both groups were flat mounted and retinal vessels were labeled with Isolectin-B4. Areas of Retinal Neovascularization (RNV) and vaso-obliteration were measured by Image-J and normalized to total retinal areas. SPARC expression was analyzed in both groups at p14 and p17 in retinal homogenates and sections by Western Blotting (WB) and immunofluorescence respectively. Human Retinal Endothelial Cells (HRECs) were exposed to hypoxia (1% O2) for 6 hours then SPARC was measured in cell lysate and condition medium by WB and ELISA. Moreover, HRECs were treated with VEGF or SPARC to study their mutual regulatory effect.

RESULTS

SPARC-deficient mice demonstrated significant increase in the vaso-obliteration (p=0.03) and modest increase in RNV compared to the wt control. Retinal levels of SPARC was significantly decreased during OIR at p14 (p=0.01) and partially restored to normal level by p17. Moreover, hypoxia significantly reduced SPARC expression and secretion in HRECs (p=0.001). We noticed a mutual positive regulatory feedback between SPARC and VEGF.

CONCLUSION

SPARC deletion enhances ischemic retinopathy, thus modulation of SPARC expression could be a novel therapeutic approach to prevent pathological RNV.

SPARC is associated with carcinogenesis of oral squamous epithelium and consistent with cell competition

The matricellular protein, secreted protein acidic and rich in cysteine (SPARC) is thought to be involved in cell competition. The objective of this study is to investigate the role of SPARC in cancerization of oral squamous epithelium. Clinical specimens from 57 pre- and early cancerous lesion, 66 invasive squamous cell carcinoma (SCC) and controls were immunostained with SPARC. Clinical features and SPARC expression were evaluated. Furthermore, effects of SPARC knockdown and overexpression were examined in oral cancer and keratinocyte cell lines. Leukoplakia, carcinoma in situ, and early invasive SCC had more SPARC-positive cells than normal mucous epithelium. However, there were no significant differences between leukoplakia, carcinoma in situ, and early SCC, and there were no correlations between SPARC immunoreactivity and prognosis of invasive oral SCCs. Cell proliferation was down-regulated by SPARC siRNA, and enhanced by SPARC transformed keratinocytes. But SPARC overexpression did not enhance cell migration activity. SPARC is induced by dysplastic cells in the early stage of cancerization, and may improve survival capability, but is not involved in malignancy. SPARC may act to escape from elimination by cell competition.

Re-sensitization of 5-FU resistance by SPARC through negative regulation of glucose metabolism in hepatocellular carcinoma

Secreted protein, acidic and rich in cysteine (SPARC), a calcium-binding matricellular glycoprotein, is implicated in the progression of many cancers. Currently, there is growing evidence for important functions of SPARC in a variety of cancers and its role in cancer depends on tumor types. In this study, we reported SPARC negatively regulated glucose metabolism in hepatocellular carcinoma (HCC). Overexpression of SPARC inhibited glucose uptake and lactate product through downregulation of key enzymes of glucose metabolism. On the other hand, knock down of SPARC reversed the phenotypes. Meanwhile, exogenous expression of SPARC in HepG2 cells resulted in tolerance to low glucose and was correlated with AMPK pathway. Interestingly, the 5-fluorouracil (5-FU)-resistant HepG2 cells showed increased glucose metabolism and downregulated SPARC levels. Finally, we reported the overexpression of SPARC re-sensitize 5-FU-resistant cells to 5-FU through inhibition of glycolysis both in vitro and in vivo. Our study proposed a novel function of SPARC in the regulation of glucose metabolism in hepatocellular carcinoma and will facilitate the development of therapeutic strategies for the treatments of liver tumor patients.

Vascular Endothelial Growth Factor in Colonic Cancer, Ulcerative Colitis and Colonic Adenoma: An Immunohistochemical Study

BACKGROUND: Colon cancer is one of the most common malignancies worldwide. Colonic adenoma and ulcerative colitis (UC) are important precancerous lesions. Vascular Endothelial Growth Factor (VEGF) is a well-known pro-angiogenic factor plays important role in physiologic and pathologic conditions and in neovascularization in cancer and hence becomes a potential target for anti-angiogenic cancer therapy.AIM: This study investigated VEGF immunohistochemical expression in colon cancer and its precancerous lesions. MATERIAL AND METHODS:  Paraffin blocks from two hospitals were collected in a year: Colon cancer: 20 cases, colonic adenoma: 15 cases, UC: 15 cases and 5 controls from normal mucosa. VEGF was assessed immunohistochemically using a primary anti-VEGF antibody (VG1, Dako, Denemark).RESULTS: Median age was 49 years (range 31-52) in cancer, 40 years (range 31-52) in adenomas and 33 years (range 27-43) in UC. VEGF expression was negative in control, significantly strongly positive in 90% of colonic adenocarcinoma (p= 0.001), significantly positive in adenomas (p= 0.002) - the weak positivity significantly seen in mild dysplasia (p= 0.001) - and significantly positive in 73.3% of UC cases (p=0.022).CONCLUSION: The significant increase in positivity of VEGF in precancerous to cancerous lesions may point to its potential role in the pathogenesis and progression of colonic neoplasia.

SPARC expression is negatively correlated with clinicopathological factors of gastric cancer and inhibits malignancy of gastric cancer cells

Secreted protein acidic and rich in cysteine (SPARC) is a glycoprotein which plays multiple roles in different types of cancer. Our previous study showed that SPARC overexpression inhibited the growth and angiogenesis of tumors, and reduced expression of vascular endothelial growth factor (VEGF). However, the relationship between SPARC expression and clinicopathological factors of gastric cancer (GC) is controversial, and the role of SPARC in GC remains unclear. We evaluated expression of SPARC in 65 human GC tissues using immunohistochemistry (IHC). The results indicated that SPARC expression was negatively correlated with clinicopathological factors of GC. In vitro assay showed that SPARC overexpression decreased proliferation and clonogenicity by suppressing CD44 expression. In addition, SPARC overexpression inhibited VEGF induced proliferation and arrested cell cycle of GC cells by reducing the activation of VEGFR2, ERK1/2 and AKT signaling pathways. SPARC suppressed the invasion and migration of GC by reducing MMP-7, MMP-9, N-cadherin, Sp1 and p-ERK1/2 expression. In the in vivo assay, cancer metastasis mouse models were established by tail vein injection. The results revealed that the lung metastases of SPARC-overexpressing GC cells in the mice were much fewer than those of control cells.

Relationships of alpha-SMA-positive fibroblasts and SDF-1-positive tumor cells with neoangiogenesis in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is one of the most prevalent malignant tumors with poor prognosis in Southern China and Southeast Asia. Angiogenesis-related molecules can be promising therapeutic targets in NPC. To investigate the relationships of cancer-associated fibroblasts (CAFs) and chemokine-related molecules with neoangiogenesis, we compared immunohistochemical analyses of alpha-smooth-muscle actin (α-SMA), stroma-derived factor-1 (SDF-1), and its receptor CXCR4 in primary NPC specimens and chronic nasopharyngitis tissues. In addition, we examined the expression of vascular endothelial growth factor (VEGF-A), and CD133- and VEGF- receptor-2 (VEGFR-2) double positive cells, as endothelial progenitor cells (EPCs). We also assessed CD34-positive microvessels. Significantly higher expression of α-SMA was observed in fibroblasts in NPC stroma. The immunoreactive intensities of SDF-1 and CXCR4 were significantly higher in NPC cells. CXCR4-positive cells and CD133/VEGFR-2- double positive cells were observed in the stroma surrounding cancer nests, and VEGF was detected in both cancer and stromal cells. Microvessel density was significantly higher in the stroma of NPC tissues compared to chronic nasopharyngitis tissues. Our data suggest that CAFs and NPC tumor cells may enhance neoangiogenesis in a VEGF- and SDF-1-dependent manner by recruiting EPCs from the bone marrow into tumor stroma.

Can vascular endothelial growth factor and microvessel density be used as prognostic biomarkers for colorectal cancer? A systematic review and meta-analysis

Background. Vascular endothelial growth factor (VEGF) and microvessel density (MVD) are associated with greater incidence of metastases and decreased survival. Whether they can be used as prognostic indicators of colorectal cancer (CRC) is still controversial. Methods. The authors performed a meta-analysis using the results of a literature search of databases of PubMed and EMBASE, and the references of articles included in the analysis. Meta-analysis was performed using random effects model and hazard ratios (HRs) and 95% confidence intervals (CIs) as effect measures. Results. Twenty studies contributed to the analysis of VEGF, of which 16 were used for overall survival (OS) and 9 for disease-free survival (DFS). High VEGF levels has a relationship with unfavorable survival (OS: HR = 1.98, 95% CI: 1.30–3.02; DFS: HR = 2.10, 95% CI: 1.26–3.49) and a 4.22-fold increase in the rate of distant metastases. Analysis was performed on 18 studies for MVD; the results showed that patients with high MVD expression in tumors appeared to have poorer overall survival (HR = 1.39, 95% CI: 1.22–1.58) and were at a greater risk of having unfavorable clinical characteristics related to prognosis. Corresponding results were obtained from quantitative and/or qualitative analysis of clinicopathological. Conclusions. The meta-analysis demonstrates that VEGF and MVD can be used as prognostic biomarkers for CRC patients.

SPARC promotes leukemic cell growth and predicts acute myeloid leukemia outcome

Aberrant expression of the secreted protein, acidic, cysteine-rich (osteonectin) (SPARC) gene, which encodes a matricellular protein that participates in normal tissue remodeling, is associated with a variety of diseases including cancer, but the contribution of SPARC to malignant growth remains controversial. We previously reported that SPARC was among the most upregulated genes in cytogenetically normal acute myeloid leukemia (CN-AML) patients with gene-expression profiles predictive of unfavorable outcome, such as mutations in isocitrate dehydrogenase 2 (IDH2-R172) and overexpression of the oncogenes brain and acute leukemia, cytoplasmic (BAALC) and v-ets erythroblastosis virus E26 oncogene homolog (ERG). In contrast, SPARC was downregulated in CN-AML patients harboring mutations in nucleophosmin (NPM1) that are associated with favorable prognosis. Based on these observations, we hypothesized that SPARC expression is clinically relevant in AML. Here, we found that SPARC overexpression is associated with adverse outcome in CN-AML patients and promotes aggressive leukemia growth in murine models of AML. In leukemia cells, SPARC expression was mediated by the SP1/NF-κB transactivation complex. Furthermore, secreted SPARC activated the integrin-linked kinase/AKT (ILK/AKT) pathway, likely via integrin interaction, and subsequent β-catenin signaling, which is involved in leukemia cell self-renewal. Pharmacologic inhibition of the SP1/NF-κB complex resulted in SPARC downregulation and leukemia growth inhibition. Together, our data indicate that evaluation of SPARC expression has prognosticative value and SPARC is a potential therapeutic target for AML.

Proangiogenic tumor proteins as potential predictive or prognostic biomarkers for bevacizumab therapy in metastatic colorectal cancer

Tumor biomarkers to more accurately predict a patient's response to a given therapy are much needed in oncology practice. For metastatic colorectal cancer the anti-vascular endothelial growth factor (VEGF) monoclonal antibody bevacizumab is now commonly included in first-line therapy regimens and has led to modest but significant improvements in patient outcomes compared with chemotherapy. Given the modest gains there is a pressing need for predictive biomarkers to better identify patients who would benefit from this targeted therapy. We used a multiplex protein assay to determine the tumor expression levels of the proangiogenic proteins IL-6, IL-8, bFGF, PDGF-BB and VEGF-A in formalin-fixed paraffin-embedded tumors from the MAX clinical trial patients with available tissue samples. Patients were dichotomized into "low" vs. "high" expression subgroups based on median baseline levels to correlate with objective response rate (ORR), progression-free survival (PFS) and overall survival (OS). "Low" tumor VEGF-A level was predictive of better ORR for bevacizumab [ORR (low) 53% vs. (high) 19%, interaction p = 0.03] but not for PFS [hazard ratio, HR (low) 0.73 vs. (high) 0.62, interaction p = 0.68] in the comparison of capecitabine (C) versus C and bevacizumab (CB) and CB plus mitomycin (M). When analyzed as a dichotomized variable, "high" VEGF-A was prognostic for shorter PFS (unadjusted HR 1.34, p = 0.06; adjusted HR 1.55, p = 0.008). The other four proteins were neither predictive of bevacizumab benefits nor prognostic for ORR, PFS or OS. "Low" tumor VEGF-A was associated with longer PFS after adjustment for other baseline factors. Proangiogenic proteins were not predictive of benefit with bevacizumab for PFS.