Tumor-stroma interactions: their role in the control of tumor cell invasion

The role of thrombin in the paradoxical interplay of cancer metastasis and the vascular system: A driving dynamic

The coagulation system plays a complex role in cancer therapy. Endothelial damage and tissue factor increased by chemotherapy initiate the coagulation cascade, producing active FXa and releasing thrombin. Thrombin triggers tumor growth and metastasis, leading to severe thromboembolic events in cancer patients. Direct thrombin inhibitors do not have the expected anti-metastatic effect as PAR-2 remains active and increases the risk of bleeding. Therefore, dual inhibition of thrombin by FXa inhibition and plasmin inhibition, which converts fibrin to fibrinogen, is targeted. Clinical studies show that the use of tranexamic acid in patients on NOAC therapy may be beneficial without increasing the risk of bleeding. This approach offers a promising strategy to provide an anti-metastatic effect in cancer treatment.

Comprehensive Analysis of ADAMTS Gene Family in Renal Clear Cell Carcinoma and ADAMTS10 Research Combining Magnetic Resonance Imaging

Clear cell renal carcinoma (ccRCC) is one of the cancers that posed a severe threat to human life on a global scale. The ADAMTS family has been proven to be involved in a number of tumor types, although it is yet unknown how they relate to ccRCC. The mRNA expression matrix and other clinically relevant information of 607 ccRCC were sourced from TCGA database. The role of ADAMTS family genes in ccRCC was determined by differential gene expression analysis and gene set enrichment analysis (GSEA). Employing stage grading, gene mutation, and survival analysis, the genes most linked to the prognosis of ccRCC were identified. The influence of genes on the pathway was determined by Kyoto Encyclopedia of Genes and Genes (KEGG) analysis. Following that, the gene's impact on ccRCC was verified by qRT-PCR, WB, MTT, Transwell detection, and a wound healing assay. Bioinformatics analysis showed that ADAMTS10 was overexpressed in cancerous tissues of people with ccRCC and its expression increased with tumor grade. Mutation analysis showed that the main cause of mutation in the ADAMTS family gene was amplification. The prognosis and survival of the ADAMTS10 elevated expression group were lower than those of the poorly expressed group, as demonstrated by a survival analysis. On the basis of the findings of MRI, we examined 60 clinical patients and collected their cancer along with the surrounding tissues. The results of qPCR detection showed that the expression of ADAMTS10 was considerably higher in cancerous regions of 60 clinical users than it was in the tissues nearby. Inhibiting ADAMTS10 development prevents cancer cells from proliferating, invading, and migrating. The KEGG analysis links ADAMTS10 to the NF-κB signal pathway. WB experiment confirmed that inhibiting ADAMTS10 expression can inhibit the activation of the NF-κB signal pathway. ADAMTS10 may be a promising prognostic marker for ccRCC that can be employed independently.

New insight into the role of the ADAM protease family in breast carcinoma progression

Protease and adhesion molecules play a very emphasized role in the occurrence or progression of metastasis in many types of cancers. In this context, a molecule that contains both protease and adhesion functions play a crucial role in metastasis. ADAMs (a disintegrin and metalloprotease) are molecules with this special characteristic. Recently, a lot of attention has been attracted to various ADAM molecules and researchers have tried to elucidate the role of ADAMs in breast cancer occurrence and progression. Disrupting ADAMs protease and adhesion capabilities can lead to the discovery of worthy therapeutic targets in breast cancer treatment. In this review, we intend to discuss the mechanism of action of various ADAM molecules, their relation to pathogenic processes of breast cancer, and their potential as possible targets for breast cancer treatment.

Pharmacogenomic and epigenomic approaches to untangle the enigma of IL-10 blockade in oncology

The host immune system status remains an unresolved mystery among several malignancies. An immune-compromised state or smart immune-surveillance tactics orchestrated by cancer cells are the primary cause of cancer invasion and metastasis. Taking a closer look at the tumour-immune microenvironment, a complex network and crosstalk between infiltrating immune cells and cancer cells mediated by cytokines, chemokines, exosomal mediators and shed ligands are present. Cytokines such as interleukins can influence all components of the tumour microenvironment (TME), consequently promoting or suppressing tumour invasion based on their secreting source. Interleukin-10 (IL-10) is an interlocked cytokine that has been associated with several types of malignancies and proved to have paradoxical effects. IL-10 has multiple functions on cellular and non-cellular components within the TME. In this review, the authors shed the light on the regulatory role of IL-10 in the TME of several malignant contexts. Moreover, detailed epigenomic and pharmacogenomic approaches for the regulation of IL-10 were presented and discussed.

Classification of IDH wild-type glioblastoma tumorspheres into low- and high-invasion groups based on their transcriptional program

BACKGROUND

Glioblastoma (GBM), one of the most lethal tumors, exhibits a highly infiltrative phenotype. Here, we identified transcription factors (TFs) that collectively modulate invasion-related genes in GBM.

METHODS

The invasiveness of tumorspheres (TSs) were quantified using collagen-based 3D invasion assays. TF activities were quantified by enrichment analysis using GBM transcriptome, and confirmed by cell-magnified analysis of proteome imaging. Invasion-associated TFs were knocked down using siRNA or shRNA, and TSs were orthotopically implanted into mice.

RESULTS

After classifying 23 patient-derived GBM TSs into low- and high-invasion groups, we identified active TFs in each group-PCBP1 for low invasion, and STAT3 and SRF for high invasion. Knockdown of these TFs reversed the phenotype and invasion-associated-marker expression of GBM TSs. Notably, MRI revealed consistent patterns of invasiveness between TSs and the originating tumors, with an association between high invasiveness and poor prognosis. Compared to controls, mice implanted with STAT3- or SRF-downregulated GBM TSs showed reduced normal tissue infiltration and tumor growth, and prolonged survival, indicating a therapeutic response.

CONCLUSIONS

Our integrative transcriptome analysis revealed three invasion-associated TFs in GBM. Based on the relationship among the transcriptional program, invasive phenotype, and prognosis, we suggest these TFs as potential targets for GBM therapy.

An artificial intelligence prediction model based on extracellular matrix proteins for the prognostic prediction and immunotherapeutic evaluation of ovarian serous adenocarcinoma

Background: Ovarian Serous Adenocarcinoma is a malignant tumor originating from epithelial cells and one of the most common causes of death from gynecological cancers. The objective of this study was to develop a prediction model based on extracellular matrix proteins, using artificial intelligence techniques. The model aimed to aid healthcare professionals to predict the overall survival of patients with ovarian cancer (OC) and determine the efficacy of immunotherapy. Methods: The Cancer Genome Atlas Ovarian Cancer (TCGA-OV) data collection was used as the study dataset, whereas the TCGA-Pancancer dataset was used for validation. The prognostic importance of 1068 known extracellular matrix proteins for OC were determined by the Random Forest algorithm and the Lasso algorithm establishing the ECM risk score. Based on the gene expression data, the differences in mRNA abundance, tumour mutation burden (TMB) and tumour microenvironment (TME) between the high- and low-risk groups were assessed. Results: Combining multiple artificial intelligence algorithms we were able to identify 15 key extracellular matrix genes, namely, AMBN, CXCL11, PI3, CSPG5, TGFBI, TLL1, HMCN2, ESM1, IL12A, MMP17, CLEC5A, FREM2, ANGPTL4, PRSS1, FGF23, and confirm the validity of this ECM risk score for overall survival prediction. Several other parameters were identified as independent prognostic factors for OC by multivariate COX analysis. The analysis showed that thyroglobulin (TG) targeted immunotherapy was more effective in the high ECM risk score group, while the low ECM risk score group was more sensitive to the RYR2 gene-related immunotherapy. Additionally, the patients with low ECM risk scores had higher immune checkpoint gene expression and immunophenoscore levels and responded better to immunotherapy. Conclusion: The ECM risk score is an accurate tool to assess the patient's sensitivity to immunotherapy and forecast OC prognosis.

Promalignant effects of antiangiogenics in the tumor microenvironment

Antiangiogenic therapies are considered a promising strategy against solid tumors. Their aim is to inhibit the formation of new blood vasculature, thereby reducing the oxygen and nutrient supply to prevent further tumor growth and spreading. However, the strategy has seen limitations, as survival benefits are modest and often accompanied with increased tumor aggressiveness in form of invasion and metastasis. Antiangiogenic induced changes in the tumor microenvironment, such as hypoxia, mechanical stress or extracellular acidification can activate different receptors of tumoral and stromal cells and induce an extensive remodeling of the entire tumor microenvironment, with the overall goal to invade nearby tissues and regain access to the vasculature. In this regard, receptor tyrosine kinases have been studied intensively and especially the inhibition of c-Met has given promising results, characterized by a reduction in invasiveness and prolonged survival. Receptors that sense changes in the extracellular matrix like integrins or proteoglycans can also induce downstream signaling that stimulates the expression of remodeling factors such as new matrix components, enzymes or chemoattractants. Targeting multiple receptors and sensors of cancer cells simultaneously might represent an effective second line treatment that prevents the formation of malignant side effects.

Personalized models of heterogeneous 3D epithelial tumor microenvironments: Ovarian cancer as a model

Intractable human diseases such as cancers, are context dependent, unique to both the individual patient and to the specific tumor microenvironment. However, conventional cancer treatments are often nonspecific, targeting global similarities rather than unique drivers. This limits treatment efficacy across heterogeneous patient populations and even at different tumor locations within the same patient. Ultimately, this poor efficacy can lead to adverse clinical outcomes and the development of treatment-resistant relapse. To prevent this and improve outcomes, it is necessary to be selective when choosing a patient's optimal adjuvant treatment. In this review, we posit the use of personalized, tumor-specific models (TSM) as tools to achieve this remarkable feat. First, using ovarian cancer as a model disease, we outline the heterogeneity and complexity of both the cellular and extracellular components in the tumor microenvironment. Then we examine the advantages and disadvantages of contemporary cancer models and the rationale for personalized TSM. We discuss how to generate precision 3D models through careful and detailed analysis of patient biopsies. Finally, we provide clinically relevant applications of these versatile personalized cancer models to highlight their potential impact. These models are ideal for a myriad of fundamental cancer biology and translational studies. Importantly, these approaches can be extended to other carcinomas, facilitating the discovery of new therapeutics that more effectively target the unique aspects of each individual patient's TME. STATEMENT OF SIGNIFICANCE: In this article, we have presented the case for the application of biomaterials in developing personalized models of complex diseases such as cancers. TSM could bring about breakthroughs in the promise of precision medicine. The critical components of the diverse tumor microenvironments, that lead to treatment failures, include cellular- and extracellular matrix- heterogeneity, and biophysical signals to the cells. Therefore, we have described these dynamic components of the tumor microenvironments, and have highlighted how contemporary biomaterials can be utilized to create personalized in vitro models of cancers. We have also described the application of the TSM to predict the dynamic patterns of disease progression, and predict effective therapies that can produce durable responses, limit relapses, and treat any minimal residual disease.

COL11A1 activates cancer-associated fibroblasts by modulating TGF-β3 through the NF-κB/IGFBP2 axis in ovarian cancer cells

Ovarian cancer has a unique tumor microenvironment (TME) that enables cancer-associated fibroblasts (CAFs) to interact with cellular and matrix constituents and influence tumor development and migration into the peritoneal cavity. Collagen type XI alpha 1 (COL11A1) is overexpressed in CAFs; therefore this study examines its role during CAF activation in epithelial ovarian cancer (EOC). Coculturing human ovarian fibroblasts (HOFs) with high COL11A1-expressing EOC cells or exposure to the conditioned medium of these cells prompted the expression of COL11A1 and CAF phenotypes. Conversely, coculturing HOFs with low COL11A1-expressing EOC cells or COL11A1-knockdown abrogated COL11A1 overexpression and secretion, in addition to CAF activation. Increased p-SP1 expression attributed to COL11A1-mediated extracellular signal-regulated kinase activation (ERK) induced p65 translocation into the nucleus and augmented its binding to the insulin-like growth factor binding protein 2 (IGFBP2) promoter, ultimately inducing TGF-β3 activation. The CAF-cancer cell crosstalk triggered interleukin-6 release, which in turn promoted EOC cell proliferation and invasiveness. These in vitro results were confirmed by in vivo findings in a mouse model, showing that COL11A1 overexpression in EOC cells promoted tumor formation and CAF activation, which was inhibited by TGF-β3 antibody. Human tumors with high TGF-β3 levels showed elevated expression of COL11A1 and IGFBP2, which was associated with poor survival. Our findings suggest the possibility that anti-TGF-β3 treatment strategy may be effective in targeting CAFs in COL11A1-positive ovarian tumors.

Tumour-derived substrate-adherent cells promote neuroblastoma survival through secreted trophic factors

Neuroblastoma (NB) is the most common extracranial solid tumour in children. NB is highly heterogeneous and is comprised of a mixture of neuroblastic cancer cells and stromal cells. We previously reported that N‐type cells (neuroblastic cells) and S‐type cells (substrate‐adherent cells) in the SK‐N‐SH cell line shared almost identical genetic backgrounds. Sublines of N‐ and S‐type cells were isolated from an early passage (P35) of SK‐N‐SH. Sequencing analysis revealed that all sublines harboured the anaplastic lymphoma kinase (ALK) F1174L mutation, indicating that they were tumour derived. Surprisingly, over 74% resembled S‐type cells. In coculture experiments, S‐type cells protected N‐type cells from apoptosis induced by the oncogenic ALK inhibitor TAE684. Western blotting analyses showed that ALK, protein kinase A (AKT) and STAT3 signalling were stimulated in the cocultures. Furthermore, the conditioned medium from S‐type cells activated these downstream signalling molecules in the N‐type cells. The activation of STAT3 in the N‐type cells was ALK‐independent, while AKT was regulated by the ALK activation status. To identify the responsible soluble factors, we used a combination of transcriptomic and proteomic analysis and found that plasminogen activator inhibitor 1, secreted protein acidic and cysteine rich, periostin and galectin‐1 were potential mediators of STAT3 signalling. The addition of recombinant proteins to the tumour cells treated with the ALK inhibitor partially enhanced cell viability. Overall, the tumour‐derived S‐type cells prevented apoptosis in the N‐type cells via ALK‐independent STAT3 activation triggered by secreted factors. The inhibition of these factors in combination with ALK inhibition could provide a new direction for targeted therapies to treat high‐risk NB.

Metalloprotease ADAMTS-1 decreases cell migration and invasion modulating the spatiotemporal dynamics of Cdc42 activity

ADAMTSs (A Disintegrin And Metalloproteinase with ThromboSpondin motifs) are secreted proteases dependent on Zn2+/Ca2+, involved in physiological and pathological processes and are part of the extracellular matrix (ECM). Here, we investigated if ADAMTS-1 is required for invasion and migration of cells and the possible mechanism involved. In order to test ADAMTS-1's role in ovarian cancer cells (CHO, NIH-OVCAR-3 and ES2) and NIH-3 T3 fibroblasts, we modified the levels of ADAMTS-1 and compared those to parental. Cells exposed to ADAMTS-1-enriched medium exhibited a decline in cell migration and invasion when compared to controls with or without a functional metalloproteinase domain. The opposite was observed in cells when ADAMTS-1 was deleted via the CRISPR/Cas9 approach. The decline in ADAMTS-1 levels enhanced the phosphorylated form of Src and FAK. We also evaluated the activities of cellular Rho GTPases from cell lysates using the GLISA® kit. The Cdc42-GTP signal was significantly increased in the CRISPR ADAMTS-1 ES-2 cells. By a Förster resonance energy transfer (FRET) biosensor for Cdc42 activity in ES-2 cells we demonstrated that Cdc42 activity was strongly polarized at the leading edge of migrating cells with ADAMTS-1 deletion, compared to the wild type cells. As conclusion, ADAMTS-1 inhibits proliferation, polarization and migration.

Role of extra cellular proteins in gastric cancer progression and metastasis: an update

Background

Gastric cancer (GC) is one of the most common cancers in the world with a high ratio of mortality. Regarding the late diagnosis, there is a high ratio of distant metastasis among GC cases. Despite the recent progresses in therapeutic modalities, there is not still an efficient therapeutic method to increase survival rate of metastatic GC cases.

Main body

Apart from the various intracellular signaling pathways which are involved in tumor cell migration and metastasis, the local microenvironment is also a critical regulator of tumor cell migration. Indeed, the intracellular signaling pathways also exert their final metastatic roles through regulation of extra cellular matrix (ECM). Therefore, it is required to assess the role of extra cellular components in biology of GC.

Conclusion

In the present review, we summarize 48 of the significant ECM components including 17 ECM modifying enzymes, seven extracellular angiogenic factors, 13 cell adhesion and cytoskeletal organizers, seven matricellular proteins and growth factors, and four proteoglycans and extra cellular glycoproteins. This review paves the way of determination of a specific extra cellular diagnostic and prognostic panel marker for the GC patients.

Characterization and distribution of sialic acids in human testicular seminoma

Aberrant content of sialic acids (Sias) has been observed in various human cancer types in different organs. Sias have been implicated in cancerous transformation, invasiveness and metastasis, and in the escaping of cancer cells from immune surveillance. Indeed, Sias are commonly regarded as important biomarkers to distinguish cancer cells from their healthy counterparts. However, scarce and not exhaustive investigations have been performed on Sia content in testicular cancers and, in particular, in seminoma, one of the most common malignant testicular tumors. Hence, the aim of this study was to investigate the content and distribution of Sias with different glycosidic linkage, namely α2,3 and α2,6 galactose- or N-acetyl-galactosamine-linked Sias and polymeric Sia (polySia), in the germinal and stromal components of human testes affected by seminoma compared to normal testicular tissue. Structural changes in seminoma tissue were examined using hematoxylin-eosin staining. α2,3 and α2,6 linked Sias were evaluated by lectin histochemistry (Maackia amurensis agglutinin (MAA) and Sambucus nigra agglutinin (SNA)), while confocal immunofluorescence was used for polySia detection. Histopathological findings in seminoma tissue included loss of seminiferous tubules replaced by clusters of uniform polygonal cells with a clear cytoplasm, bundles of fibrotic tissue, numerous microvessels and some atrophic tubules. The content of α2,3 and α2,6 linked Sias was lost in almost all seminoma components respect to normal tissue, with the exception of microvessels in which it was higher. On the contrary, polySia level was increased in all the seminoma components compared to normal testicular tissue. Our findings suggest that an aberrant content of different Sias might have important and differential roles in seminoma development and progression. In particular, polySia might be implicated in seminoma progression by promoting cancer invasiveness and regulating the cross-talk between cancer cells, reactive stroma and vessels. Thus, the possibility that polySia might represent an important biomarker for seminoma deserves further investigation.

Changes in the telocyte/CD34+ stromal cell and α-SMA+ myoid cell networks in human testicular seminoma

Telocytes (TCs), also known as CD34+ stromal/interstitial cells, have recently been identified within the connective tissue of a variety of organs including the normal human testis. Testicular TCs appear to constitute a widespread reticular network distributed either in the peritubular or in the intertubular stromal spaces where they have been suggested to play different roles, such as participation to testis morphogenesis, postnatal preservation of the normal tissue/organ three-dimensional structure, and regulation of spermatogenesis and androgen hormone secretion and release. Although increasing evidence indicates that TCs may be involved in the pathophysiology of various diseases, no study has yet reported possible changes in these cells within the stromal compartment of seminoma, one of the most frequent malignant testicular cancers in humans. Therefore, here we carried out the first investigation of the presence and tissue distribution of TCs/CD34+ stromal cells in human testicular seminoma in comparison with normal human testis using either CD34 immunohistochemistry or CD34/CD31 and CD34/α-smooth muscle actin (α-SMA) double immunofluorescence analyses. In seminoma tissue sections, we observed an overall loss of TCs (CD34+/CD31- stromal cells) accompanying a severe degeneration of the normal architecture of seminiferous tubules and stromal tissue associated with dense cellularity increase and presence of interstitial fibrosis. Noteworthy, in the seminoma tissue the disappearance of TCs was paralleled by an expansion of α-SMA+ myoid cells. Moreover, the CD34+/CD31+ blood vessel network was greatly expanded, while steroidogenic Leydig cells were undetectable in seminoma specimens. Since TCs are emerging as important regulators of tissue and organ homeostasis, collectively the present findings indicate that the possible pathophysiologic implications of the loss of TCs in human testicular seminoma should not be further overlooked.

Preferential Tumor Accumulation of Polyglycerol Functionalized Nanodiamond Conjugated with Cyanine Dye Leading to Near-Infrared Fluorescence In Vivo Tumor Imaging

Preferential accumulation of nanoparticles in a tumor is realized commonly by combined effects of active and passive targeting. However, passive targeting based on an enhanced permeation and retention (EPR) effect is not sufficient to observe clear tumor fluorescence images in most of the in vivo experiments using tumor-bearing mice. Herein, polyglycerol-functionalized nanodiamonds (ND-PG) conjugated with cyanine dye (Cy7) are synthesized and it is found that the resulting ND-PG-Cy7 is preferentially accumulated in the tumor, giving clear fluorescence in in vivo and ex vivo fluorescence images. One of the plausible reasons is the longer in vivo blood circulation time of ND-PG-Cy7 (half-life: 58 h determined by the pharmacokinetic analysis) than that of other nanoparticles (half-life: <20 h in most of the previous reports). In a typical example, the fluorescence intensity of tumors increases due to continuous tumor accumulation of ND-PG-Cy7, even more than one week postinjection. This may be owing to the stealth effect of PG that was reported previously, avoiding recognition and excretion by reticuloendothelial cells, which are abundant in liver and spleen. In fact, the fluorescence intensities from the liver and spleen is similar to those from other organs, while the tumor exhibits much stronger fluorescence in the ex vivo image.

Targeting the tumour stroma to improve cancer therapy

Cancers are not composed merely of cancer cells alone; instead, they are complex 'ecosystems' comprising many different cell types and noncellular factors. The tumour stroma is a critical component of the tumour microenvironment, where it has crucial roles in tumour initiation, progression, and metastasis. Most anticancer therapies target cancer cells specifically, but the tumour stroma can promote the resistance of cancer cells to such therapies, eventually resulting in fatal disease. Therefore, novel treatment strategies should combine anticancer and antistromal agents. Herein, we provide an overview of the advances in understanding the complex cancer cell-tumour stroma interactions and discuss how this knowledge can result in more effective therapeutic strategies, which might ultimately improve patient outcomes.

Association between tumor-stroma ratio and prognosis in solid tumor patients: a systematic review and meta-analysis

Tumor-related stroma plays an active role in tumor invasion and metastasis. The tumor–stroma ratio (TSR) in the pathologic specimen has drawn increasing attention from the field of predicting tumor prognosis. However, the prognostic value of TSR in solid tumors necessitates further elucidation. We conducted a meta-analysis on 14 studies with 4238 patients through a comprehensive electronic search on databases updated on May 2016 to explore the relationship between TSR and prognosis of solid tumors. The overall hazard ratio showed that rich stroma in tumor tissue was associated with poor overall survival (OS) (14 studies, 4238 patients) and disease-free survival (DFS) (9 studies, 2235 patients) of patients with solid tumors. The effect of low TSR on poor OS was observed among various cancer types, but not in the early stage of cervical caner. A significant relationship between low TSR and poor OS was also observed in the subgroup analyses based on study region, blinding status, and Newcastle–Ottawa Scale (NOS) score. Subgroup analyses indicated that cancer type, clinical stage, study region, blinding status, and NOS score did not affect the prognostic value of TSR for DFS. Moreover, low TSR was significantly correlated with the serious clinical stage, advanced depth of invasion, and positive lymph node metastasis. These findings indicate that a high proportion of stroma in cancer tissue is associated with poor clinical outcomes in cancer patients, and TSR may serve as an independent prognostic factor for solid tumors.

The Potential Roles of MELF-Pattern, Microvessel Density, and VEGF Expression in Survival of Patients with Endometrioid Endometrial Carcinoma: A Morphometrical and Immunohistochemical Analysis of 100 Cases

Background

In this study, we hypothesized that microcystic, elongated, fragmented (MELF)-pattern, vascular endothelial growth factor (VEGF) expression by cancer cells and microvessel density of cancer stroma may be associated with progression of endometrioid adenocarcinoma.

Methods

The study used data from the Belarus Cancer Registry and archival histological material of 100 patients with retrospectively known good (survival) and poor (disease progression and death) outcomes. All cases were immunohistochemically stained for CD34 and VEGF. Two independent samples were compared for the characteristics of signs, and obtained results were analyzed by receiver operating characteristic analysis, Mann-Whitney U test, χ² test (Yates correction), and Mantel-Cox test. Multivariate Cox hazard analysis and Spearman correlation test were used. A p-value of less than .05 was considered statistically significant.

Results

The observed survival rate of patients with endometrioid adenocarcinoma was significantly lower (p = .002) in MELF-pattern positive patients when compared with MELF-pattern negative patients. The overall survival rate of patients whose tumors had more than 114 vessels/mm² of tissue was significantly low (p < .001). Interestingly, a similar observation was found in patients with increased vessel area, evidenced by VEGF expression in the glandular tumor component.

Conclusions

Our study suggests, for the first time, that these criteria may be used as risk factors of endometrioid adenocarcinoma progression during 5 years after radical surgical treatment. However, a large independent cohort of samples should be considered in the future to validate our findings.

The Oncogenic Role of COL23A1 in Clear Cell Renal Cell Carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common adult renal neoplasm and its incidence continues to increase. Collagen is the most abundant extracellular matrix protein in stroma, and contributes to the development and progression of ccRCC. We examined the human collagen type XXIII α1 chain (COL23A1) expression in ccRCC and the relationship between COL23A1 and patients' survival. We found COL23A1 mRNA was elevated in tumor compared with adjacent normal tissues, which was further validated by TCGA cohort. IHC results from 151 ccRCC cases suggested that high COL23A1 expression correlated with larger tumor size (P = 0.017) and advanced T stage (P = 0.011). The overall survival (OS) was shorter for ccRCC patients with high COL23A1 expression (P = 0.002). In multivariate analysis, high COL23A1 expression was an independent prognostic factor of OS (HR: 3.024, P = 0.017). Furthermore, COL23A1 knockdown repressed proliferation of ccRCC cell lines by blocking cell cycle progression. Cell adhesion and migration capacity was also downregulated by knockdown of COL23A1. Our data indicate that COL23A1 may be a novel prognostic indicator in ccRCC and might be a specific and accessible biomarker as well as a potential new target for clinical diagnosis of ccRCC.

Silencing of TGF-β1 in tumor cells impacts MMP-9 in tumor microenvironment

Transforming growth factor (TGF)-β1 contributes to autocrine and paracrine functions in the tumor microenvironment (TME). The present study examined the effects of TGF-β1 crosstalk in TME and its role in mediating tumor formation and progression by targeted abrogation of TGF-β1 expression in metastatic cells in situ. Using species-specific primers, we found a significant increase in MMP-9 gene expression in the tumor-reactive stroma during late-stage metastasis in the lung. This effect was also confirmed in cancer-associated fibroblasts (CAFs) when co-cultured with the tumor cells. Knockdown of TGF-β1 expression in the tumor cells negatively affected matrix metalloproteinase (MMP)-9 gene expression. Fibroblasts, cultured in the presence of tumor cells with intact TGF-β1, showed a significant increase in proliferation rate, as well as expression of VEGF, bFGF, and SDF-1, which was not seen when TGF-β1 expression was abrogated in tumor cells. Absence of TGF-β1 in tumor cells also failed to result in myofibroblast differentiation. Co-implantation of CAFs and tumor cells with either intact TGF-β1 expression or devoid of TGF-β1 in vivo showed a significant increase in tumor growth kinetics in both cell types, suggesting a possible activation TGF-β receptor signaling in tumor cells in response to TGF-β from the TME.

Biglycan stimulates VEGF expression in endothelial cells by activating the TLR signaling pathway

Biglycan (BGN) is an important component of the extracellular matrix (ECM) that is implicated in a variety of human cancers. In our previous study, we reported that BGN was overexpressed in gastric cancer (GC) tissues and promoted cancer metastasis. Moreover, the tubular formation capacity in HUVECs was promoted by stimulation with culture media from BGN-overexpressing GC cells, but the exact underlying mechanism is still unknown. The purpose of this study was to determine the role and molecular mechanism of BGN in VEGF expression in endothelial cells. We found that BGN stimulation of endothelial cells increased the interaction between NF-kB and the HIF-1α promoter, leading to enhanced promoter activity and increased HIF-1α mRNA levels, as well as augmented HIF-1 activity that resulted in VEGF expression. All of this was dependent on the interaction of BGN with its receptors, TLR2 and TLR4. Moreover, we found that BGN enhanced endothelial cell migration and proliferation, as well as tube formation, in a TLR signaling pathway-dependent manner. In addition, endothelial cell-derived VEGF in turn was found to act on GC cells and promotes their migration. The combined findings of our current and previous studies suggest that BGN secreted from GC cells into the tumor stroma promotes GC development, as well as its progression, potentially through the chronic activation of tumor angiogenesis.

The Beta Subunit of Hemoglobin (HBB2/HBB) Suppresses Neuroblastoma Growth and Metastasis

Soluble pulmonary factors have been reported to be capable of inhibiting the viability of cancer cells that metastasize to the lung, but the molecular identity was obscure. Here we report the isolation and characterization of the beta subunit of hemoglobin as a lung-derived antimetastatic factor. Peptide mapping in the beta subunit of human hemoglobin (HBB) defined a short C-terminal region (termed Metox) as responsible for activity. In tissue culture, both HBB and murine HBB2 mediated growth arrest and apoptosis of lung-metastasizing neuroblastoma cells, along with a variety of other human cancer cell lines. Metox acted similarly and its administration in human tumor xenograft models limited the development of adrenal neuroblastoma tumors as well as spontaneous lung and bone marrow metastases. Expression studies in mice indicated that HBB2 is produced by alveolar epithelial and endothelial cells and is upregulated in mice bearing undetectable metastasis. Our work suggested a novel function for HBB as a theranostic molecule: an innate antimetastasis factor with potential utility as an anticancer drug and a biomarker signaling the presence of clinically undetectable metastasis. Cancer Res; 77(1); 14-26. ©2016 AACR.

Prognostic significance of Versican expression in gastric adenocarcinoma

Gastric cancer (GC) is the leading malignancy in the digestive system. Versican is a ubiquitous component of the extracellular matrix and has a role in tumor progression. We aim to examine the expression of Versican in GC and the relationship between Versican levels and patient survival. We detected the mRNA expression of Versican in tumorous pairs and adjacent normal tissues (ANTs) of 78 GC patients by quantitative real-time polymerase chain reaction. The protein expression of Versican in 101 cases of matched GC and ANT, as well as in 27 intraepithelial neoplastic (IN) samples, was evaluated by immunohistochemistry. We analyzed the correlation between Versican levels and clinical outcomes. Finally, we performed CCK-8 cell counting assay and transwell assay in GC cell lines. Versican mRNA expression was significantly greater in tumor tissues (P<0.001) than in ANT. Versican was majorly expressed in the stroma surrounding tumor epithelium and minorly some areas of tumor epithelium. The Versican expression level was higher in GC than in ANT (P=0.004), but no significant difference was observed between ANT and IN (P=0.517). The Versican mRNA and protein levels were consistent in GC. High Versican mRNA and protein expression correlated with greater tumor invasion depth (P=0.030, P=0.027). Univariate and multivariate analysis revealed that patients with high Versican mRNA expression exhibited poor disease-specific survival (P<0.001). In vitro experiments showed that Versican overexpression promoted cell proliferation and invasion. Our data indicate that Versican may be a novel prognostic indicator in GC and may be a potential target for clinical diagnosis.

The Extracellular Matrix in Epithelial Ovarian Cancer - A Piece of a Puzzle

Epithelial ovarian cancer is the fifth leading cause of cancer-related deaths in women and the most lethal gynecological malignancy. Extracellular matrix (ECM) is an integral component of both the normal and tumor microenvironment. ECM composition varies between tissues and is crucial for maintaining normal function and homeostasis. Dysregulation and aberrant deposition or loss of ECM components is implicated in ovarian cancer progression. The mechanisms by which tumor cells induce ECM remodeling to promote a malignant phenotype are yet to be elucidated. A thorough understanding of the role of the ECM in ovarian cancer is needed for the development of effective biomarkers and new therapies.

Fibroblasts support migration of monocyte-derived dendritic cells by secretion of PGE2 and MMP-1

The outcome of a cutaneous immune response is critically dependent upon the ability of dendritic cells (DC) to migrate from skin to the draining lymph nodes - a process that is influenced by the cutaneous tissue microenvironment. Here, the role of fibroblasts - a major component of the dermal microenvironment - on the migratory capacity of monocyte-derived DC (MoDC) was investigated in a 3D collagen I matrix. Indeed, dermal fibroblasts supported the migration of pre-activated MoDC through a 3D collagen I matrix. Activation of human MoDC resulted in the release of TNFα and IL-1β that in turn stimulated MMP-1 (human collagenase) and PGE2 secretion by human dermal fibroblasts. Transmigration assays confirmed the importance of fibroblast-derived MMP-1 and PGE2 for the migration of MoDC through a 3D collagen I matrix. Finally, in mice initiation of inflammation by induction of an irritant contact dermatitis or a psoriasis-like skin inflammation, the expression of the PGE2 generating cox-2 and the mouse collagen I degrading enzyme matrix metalloproteinases (MMP)-13 was strongly up-regulated. Our study indicates that MoDC are able to instruct dermal fibroblasts resulting in enhanced migratory capability of MoDC, thus highlighting the role of a crosstalk of DC with their stromal microenvironment for the control of cutaneous immune responses.

Human mesenchymal stem cells enhance cancer cell proliferation via IL-6 secretion and activation of ERK1/2

Human mesenchymal stem cells (hMSC) are frequently used in tissue engineering. Due to their strong tumor tropism, hMSC seem to be a promising vehicle for anticancer drugs. However, interactions between hMSC and cancer are ambiguous. Particularly the cytokines and growth factors seem to play an important role in cancer progression and metastasis. The present study evaluated the effects of hMSC on head and neck squamous cell carcinoma (HNSCC) cell lines (FaDu and HLaC78) in vitro. hMSC released several cytokines and growth factors. FaDu and HLaC78 showed a significant enhancement of cell proliferation after cultivation with hMSC-conditioned medium as compared to control. This proliferation improvement was inhibited by the addition of anti-IL-6. The western blot showed an activation of Erk1/2 in FaDu and HLaC78 by hMSC-conditioned medium. HNSCC cell lines expressed EGFR. The current study confirms the importance of cytokines secreted by hMSC in cancer biology. Especially IL-6 seems to play a key role in cancer progression. Thus, the use of hMSC as a carrier for cancer therapy must be discussed critically. Future studies should evaluate the possibility of generating genetically engineered hMSC with, for example, the absence of IL-6 secretion.

Study on the diagnosis of rabbit VX2 esophageal cancer and stent-therapy efficacy based on multiphoton microscopy

Histopathology is the gold standard for diagnosis of esophageal carcinoma. Based on two photon excited fluorescence (TPEF) and second harmonic generation (SHG), multiphoton microscopy (MPM) has become a novel optical tool adjunct to current histopathological techniques without any exogenous contrast agents. We thus investigated the potential of using TPEF and SHG techniques for differentiating cancer tissues from cancer tissues after paclitaxel-eluting stent implantation and normal esophageal tissues which are fresh and unstained without dying from the VX2 esophageal carcinoma rabbit models. Comparisons were made between MPM imaging and gold standard sections for each specimen stained with hematoxylin-eosin (H&E). Our results indicated that the MPM imaging technique could identify and distinguish among normal esophageal tissues, cancer tissues, as well as cancer tissues after stent implantation. Therefore, MPM potentially offers a powerful tool to not only diagnose esophageal cancer but also monitor stent-therapy efficacy.

HGF/c-MET Axis in Tumor Microenvironment and Metastasis Formation

Tumor metastases are responsible for approximately 90% of all cancer-related deaths. Metastasis formation is a multistep process that requires acquisition by tumor cells of a malignant phenotype that allows them to escape from the primary tumor site and invade other organs. Each step of this mechanism involves a deep crosstalk between tumor cells and their microenvironment where the host cells play a key role in influencing metastatic behavior through the release of many secreted factors. Among these signaling molecules, Hepatocyte Growth Factor (HGF) is released by many cell types of the tumor microenvironment to target its receptor c-MET within the cells of the primary tumor. Many studies reveal that HGF/c-MET axis is implicated in various human cancers, and genetic and epigenetic gain of functions of this signaling contributes to cancer development through a variety of mechanisms. In this review, we describe the specific types of cells in the tumor microenvironment that release HGF in order to promote the metastatic outgrowth through the activation of extracellular matrix remodeling, inflammation, migration, angiogenesis, and invasion. We dissect the potential use of new molecules that interfere with the HGF/c-MET axis as therapeutic targets for future clinical trials in cancer disease.

Combined targeting of TGF-β1 and integrin β3 impairs lymph node metastasis in a mouse model of non-small-cell lung cancer

Background

Transforming Growth Factor beta (TGF-β) acts as a tumor suppressor early in carcinogenesis but turns into tumor promoter in later disease stages. In fact, TGF-β is a known inducer of integrin expression by tumor cells which contributes to cancer metastatic spread and TGF-β inhibition has been shown to attenuate metastasis in mouse models. However, carcinoma cells often become refractory to TGF-β-mediated growth inhibition. Therefore identifying patients that may benefit from anti-TGF-β therapy requires careful selection.

Methods

We performed in vitro analysis of the effects of exposure to TGF-β in NSCLC cell chemotaxis and adhesion to lymphatic endothelial cells. We also studied in an orthotopic model of NSCLC the incidence of metastases to the lymph nodes after inhibition of TGF-β signaling, β3 integrin expression or both.

Results

We offer evidences of increased β3-integrin dependent NSCLC adhesion to lymphatic endothelium after TGF-β exposure. In vivo experiments show that targeting of TGF-β and β3 integrin significantly reduces the incidence of lymph node metastasis. Even more, blockade of β3 integrin expression in tumors that did not respond to TGF-β inhibition severely impaired the ability of the tumor to metastasize towards the lymph nodes.

Conclusion

These findings suggest that lung cancer tumors refractory to TGF-β monotherapy can be effectively treated using dual therapy that combines the inhibition of tumor cell adhesion to lymphatic vessels with stromal TGF-β inhibition.

Stromal alterations as quantitative optical biomarkers of epithelial tumor progression

Stroma plays an important role during epithelial tumor progression. Probing stroma alteration may become an intrinsic indicator for evaluating epithelial tumor progression. In this review, we summarize our recent works on stromal alterations as quantitative optical biomarkers of epithelial tumor progression by use of nonlinear optical microscopy.

Fibroblasts protect melanoma cells from the cytotoxic effects of doxorubicin

Melanoma is the most aggressive form of skin cancer and until recently, it was extremely resistant to radio-, immuno-, and chemotherapy. Despite the latest success of BRAF V600E-targeted therapies, responses are typically short lived and relapse is all but certain. Furthermore, a percentage (40%) of melanoma cells is BRAF wild type. Emerging evidence suggests a role for normal host cells in the occurrence of drug resistance. In the current study, we compared a variety of cell culture models with an organotypic incomplete skin culture model (the "dermal equivalent") to investigate the role of the tissue microenvironment in the response of melanoma cells to the chemotherapeutic agent doxorubicin (Dox). In the dermal equivalent model, consisting of fibroblasts embedded in type I collagen matrix, melanoma cells showed a decreased cytotoxic response when compared with less complex culture conditions, such as seeding on plastic cell culture plate (as monolayers cultures) or on collagen gel. We further investigated the role of the microenvironment in p53 induction and caspase 3 and 9 cleavage. Melanoma cell lines cultured on dermal equivalent showed decreased expression of p53 after Dox treatment, and this outcome was accompanied by induction of interleukin IL-6, IL-8, and matrix metalloproteinases 2 and 9. Here, we show that the growth of melanoma cells in the dermal equivalent model inflects drug responses by recapitulating important pro-survival features of the tumor microenvironment. These studies indicate that the presence of stroma enhances the drug resistance of melanoma in vitro, more closely mirroring the in vivo phenotype. Our data, thus, demonstrate the utility of organotypic cell culture models in providing essential context-dependent information critical for the development of new therapeutic strategies for melanoma. We believe that the organotypic model represents an improved screening platform to investigate novel anti-cancer agents, as it provides important insights into tumor-stromal interactions, thus assisting in the elucidation of chemoresistance mechanisms.

Decreased expression of the FOXO3a gene is associated with poor prognosis in primary gastric adenocarcinoma patients

Background

FOXO3a, a member of the forkhead class ‘O’ (FOXO) transcription factor family, controls a wide spectrum of biological processes, such as DNA damage repair, apoptosis, and cell cycle regulation. FOXO3a has been shown to be a tumor suppressor in various cancers. This study investigated the expression of FOXO3a in primary gastric adenocarcinomas and its prognostic value for primary gastric adenocarcinoma patients.

Methods

Real-time quantitative RT-PCR (qRT-PCR), western blotting, and immunohistochemical staining were used to detect FOXO3a expression in primary gastric cancerous surgical specimens and adjacent non-tumorous tissues.

Results

Our data showed that the expression of FOXO3a mRNA (p = 0.03) and protein (p = 0.019) was lower in cancerous tissues compared with their adjacent non-tumorous tissues. In addition, the chi-square test revealed that low FOXO3a expression was significantly correlated with larger tumor size (p = 0.007), poor histopathological classification (p = 0.029), depth of invasion (p = 0.049), local lymph node metastasis (p = 0.013), distant metastasis (p = 0.013) and AJCC staging (p<0.001). Kaplan-Meier survival analysis demonstrated that low expression of FOXO3a was significantly correlated with a poor prognosis for gastric cancer patients (p<0.001). The multivariate analysis showed that FOXO3a expression was an independent prognostic factor of the overall survival rate of patients with primary gastric adenocarcinoma.

Conclusion

Our study suggested that decreased FOXO3a expression may play an important role in the progression of gastric cancer. FOXO3a could be a valuable prognostic marker as well as a potential molecular therapy target for gastric cancer patients.

Label-free detection of breast masses using multiphoton microscopy

Histopathology forms the gold standard for the diagnosis of breast cancer. Multiphoton microscopy (MPM) has been proposed to be a potentially powerful adjunct to current histopathological techniques. A label-free imaging based on two- photon excited fluorescence and second-harmonic generation is developed for differentiating normal breast tissues, benign, as well as breast cancer tissues. Human breast biopsies (including human normal breast tissues, benign as well as breast cancer tissues ) that are first imaged (fresh, unfixed, and unstained) with MPM and are then processed for routine H-E histopathology. Our results suggest that the MPM images, obtained from these unprocessed biopsies, can readily distinguish between benign lesions and breast cancers. In the tissues of breast cancers, MPM showed that the tumor cells displayed marked cellular and nuclear pleomorphism. The tumor cells, characterized by irregular size and shape, enlarged nuclei, and increased nuclear-cytoplasmic ratio, infiltrated into disrupted connective tissue, leading to the loss of second-harmonic generation signals. For breast cancer, MPM diagnosis was 100% correct because the tissues of breast cancers did not have second-harmonic generation signals in MPM imaging. On the contrary, in benign breast masses, second-harmonic generation signals could be seen easily in MPM imaging. These observations indicate that MPM could be an important potential tool to provide label-free noninvasive diagnostic impressions that can guide surgeon in biopsy and patient management.

Carcinoma-associated fibroblasts, its implication in head and neck squamous cell carcinoma: a mini review

The communication between tumor stromal and parenchymal cells provides an insight to tumor progression. One of the main elements of the stroma, a major contributor to the extracellular environment of tumors, is carcinoma-associated fibroblasts. They can originate from either normal fibroblasts in the immediate vicinity of the tumor or from circulating bone marrow-derived mesenchymal stem cells. These myofibroblasts can arise locally from an endothelial-mesenchymal transformation at the invasive edge of the cancer and are physically associated with carcinoma cells, that is, in the development of high-grade malignancies and poor prognosis. These carcinoma-associated fibroblasts feed the epithelial tumor cells in a host-parasite relationship establishing its role in head and neck squamous cell carcinoma progression.

Vitamin D: metabolism, molecular mechanisms, and mutations to malignancies

The potential protective effects of vitamin D against cutaneous carcinogenesis are still poorly understood. The inhibition, by vitamin D, of various cancers in in vitro and in vivo models has triggered detailed investigation of vitamin D effects on neoplastic behavior. Recent studies highlight that such neoplastic features as the tumor microenvironment, angiogenesis, DNA mutagenesis, and apoptosis are all connected to vitamin D metabolic pathways. This review discusses these connections. Vitamin D modulation of the cell cycle, DNA repair and apoptosis via its receptors (VDRs) may have a suppressive effect on skin cancer as some studies suggest. The regulation of multiple tumor signaling pathways by vitamin D may have an implication in cutaneous carcinogenesis and tumor progression to malignancy.

Malignant melanoma induces migration and invasion of adult mesenchymal stem cells

OBJECTIVES/HYPOTHESIS

To determine if melanoma cells secrete chemotactic factors that result in the migration of multipotent stem cells.

STUDY DESIGN

In vitro cell culture.

METHODS

Chemotaxis and invasion of human mesenchymal stem cells (hMSCs) was determined using the modified Boyden chamber assay. Quantification of growth factors secreted by melanoma cells (A375) was determined using enzyme-linked immunosorbent assay.

RESULTS

Conditioned A375 melanoma media caused significant migration and invasion of hMSCs compared to serum-free controls and conditioned media from normal melanocytes (P < .0001). The migratory effect appeared maximal after the A375 media was conditioned for 48 hours. Physiologically relevant concentrations of fibroblast growth factor-2 (FGF2) (90 pg/mL) secreted by A375 melanoma cells caused significant migration of hMSCs (P < .001) compared to serum-free and normal melanocyte controls. Neutralization of FGF2 inhibited the migration of hMSCs to that of the negative controls (conditioned media from normal melanocytes).

CONCLUSIONS

The melanoma tumor microenvironment may be maintained through chemotaxis and invasion of multipotent hMSCs, and this migratory effect appears to be mediated in part through secretion of FGF2 by melanoma cells.

Myofibroblast keratinocyte growth factor reduces tight junctional integrity and increases claudin-2 levels in polarized Caco-2 cells

The colonic epithelium is composed of a polarized monolayer sheathed by a layer of pericryptal myofibroblasts (PCMFs). We mimicked these cellular compartments in vitro to assess the effects of paracrine-acting PCMF-derived factors on tight junction (TJ) integrity, as measured by transepithelial electrical resistance (TER). Coculture with 18Co PCMFs, or basolateral administration of 18Co conditioned medium, significantly reduced TER of polarized Caco-2 cells. Among candidate paracrine factors, only keratinocyte growth factor (KGF) reduced Caco-2 TER; basolateral KGF treatment led to time- and concentration-dependent increases in claudin-2 levels. We also demonstrate that amphiregulin (AREG), produced largely by Caco-2 cells, increased claudin-2 levels, leading to epidermal growth factor receptor-mediated TER reduction. We propose that colonic epithelial TJ integrity can be modulated by paracrine KGF and autocrine AREG through increased claudin-2 levels. KGF-regulated claudin-2 induction may have implications for inflammatory bowel disease, where both KGF and claudin-2 are upregulated.

Human tumor cells induce angiogenesis through positive feedback between CD147 and insulin-like growth factor-I

Tumor angiogenesis is a complex process based upon a sequence of interactions between tumor cells and endothelial cells. Previous studies have shown that CD147 was correlated with tumor angiogenesis through increasing tumor cell secretion of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). In this study, we made a three-dimensional (3D) tumor angiogenesis model using a co-culture system of human hepatocellular carcinoma cells SMMC-7721 and humanumbilical vein endothelial cells (HUVECs) in vitro. We found that CD147-expressing cancer cells could promote HUVECs to form net-like structures resembling the neo-vasculature, whereas the ability of proliferation, migration and tube formation of HUVECs was significantly decreased in tumor conditioned medium (TCM) of SMMC-7721 cells transfected with specific CD147-siRNA. Furthermore, by assaying the change of pro-angiogenic factors in TCM, we found that the inhibition of CD147 expression led to significant decrease of VEGF and insulin-like growth factor-I (IGF-I) secretion. Interestingly, we also found that IGF-I up-regulated the expression of CD147 in both tumor cells and HUVECs. These findings suggest that there is a positive feedback between CD147 and IGF-I at the tumor-endothelial interface and CD147 initiates the formation of an angiogenesis niche.

Periostin, a stroma-associated protein, correlates with tumor invasiveness and progression in nasopharyngeal carcinoma

Recently, the tumor microenvironment is increasingly recognized as playing an important role in cancer proliferation, invasion, and metastasis. To screen stroma-associated proteins involved in nasopharyngeal carcinoma (NPC) carcinogenesis, laser capture microdissection (LCM) and quantitative proteomic analysis were employed to assess different protein expression of the stroma between NPC and normal nasopharyngeal mucosa (NNM). In this study, periostin was identified to be significantly up-regulated in NPC stroma compared with NNM stroma and the result was further confirmed by Western blotting. Immunohistochemistry showed that over-expression of periostin was frequently observed in the stroma of NPC and matched lymph node metastases (LNM) compared with the stroma of NNM. Statistical analysis showed over-expression of periostin was significantly associated with advanced clinical stage (P < 0.001) and lymph node metastasis (P < 0.001) and decreased overall survival (P < 0.001) in NPC. Cox regression analysis indicated over-expression of periostin was an independent prognostic factor. Furthermore, ectopic expression of periostin was used to examine its effect on invasiveness of NPC cell in vitro and the result showed that periostin was able to promote invasiveness of NPC cell. In conclusion, periostin expression is correlated with tumor stage, lymph node metastasis, and patient survival. Periostin is a potential biomarker for the differentiation and prognosis of NPC, and it might play an important role in the progression of NPC.

Cytoplasmic NANOG-positive stromal cells promote human cervical cancer progression

Tumor development has long been known to resemble abnormal embryogenesis. The embryonic stem cell gene NANOG, a divergent homeodomain transcription factor that is independent of leukemia inhibitory factor, has been reported to be expressed in germ cells and in several tumor types. However, the short-term expression and role of NANOG in cervical cancer remain unclear. In the present study, we demonstrate that NANOG exhibits cellular shuttling behavior and increasing stromal distribution during the progression of cervical cancer. Our molecular data using RT-PCR and restriction enzyme digestion show that NANOG is mainly transcribed from the NANOG gene in cervical cancer. In addition, IHC using confocal microscopy suggests that mesenchymal stem cells (MSCs) are one type of cytoplasmic NANOG-positive cells in cervical cancer stroma. Co-culture of cervical cancer-derived MSCs with SiHa cells showed increased proliferation characteristics in vitro and enhanced tumor growth in vivo. Our results show, for the first time to our knowledge, that MSCs are a source of cytoplasmic NANOG expression in the cervical cancer stroma and that they participate in the progression of cervical cancer both in vitro and in vivo. Our study provides evidence that NANOG is a cervical cancer progression marker and also serves as a starting point for a more extensive exploration of the cellular translocation of NANOG and the multifunctionality of the stromal microenvironment.

Stromal fibroblast-specific expression of ADAM-9 modulates proliferation and apoptosis in melanoma cells in vitro and in vivo

ADAMs are members of the zinc metalloproteinase superfamily characterized by the presence of disintegrin and metalloprotease domains. In human melanoma, ADAM-9 is expressed in focalized areas of the tumor-stroma border in both melanoma and stromal cells. However, the role of ADAM-9 in melanoma progression remains elusive. To analyze the role of stromal-derived ADAM-9 for the growth and survival of melanoma cells, we have used in vitro coculture systems of melanoma cells and ADAM-9(-/-) fibroblasts. Coculture of melanoma cells in the presence of ADAM-9(-/-) fibroblasts led to increased melanoma cell proliferation and reduced apoptosis as compared with control cocultures. We identified TIMP-1 and sTNFRI as the two relevant factors expressed in increased amounts in culture supernatants from ADAM-9(-/-) fibroblasts. TIMP-1 was associated with induced melanoma cell proliferation, whereas soluble TNFR1 mediated the reduced cellular apoptosis in vitro. In vivo, injection of murine melanoma cells into the flank of ADAM-9(-/-) animals resulted in the development of significantly larger tumors than in wild-type animals as a result of increased proliferation and decreased apoptosis of melanoma cells. Taken together, stromal expression of ADAM-9 during melanoma development modulates the expression of TIMP-1 and sTNFR1, which in turn affect tumor cell proliferation and apoptosis.

Mast cells in tumor microenvironment promotes the in vivo growth of pancreatic ductal adenocarcinoma

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer death. No effective therapy is currently available for PDAC because of the lack of understanding of the mechanisms leading to its growth and development. Inflammatory cells, particularly mast cells, have been shown to play key roles in some cancers. We carried out this study to test the hypothesis that mast cells in the tumor microenvironment are essential for PDAC tumorigenesis.

EXPERIMENTAL DESIGN

The presence of inflammatory cells at various stages of PDAC development was determined in a spontaneous mouse model of PDAC (K-ras(G12V)). The importance of mast cells was determined using orthotopically implanted PDAC cells in mast cell-deficient Kit(w-sh/w-sh) mice and further confirmed by reconstitution of wild-type bone marrow-derived mast cells. Clinical relevance was assessed by correlating the presence of mast cells with clinical outcome in patients with PDAC.

RESULTS

In the spontaneous mouse model of PDAC (K-ras(G12V)), there was an early influx of mast cells to the tumor microenvironment. PDAC tumor growth was suppressed in mast cell-deficient Kit(w-sh/w-sh) mice, but aggressive PDAC growth was restored when PDAC cells were injected into mast cell-deficient mice reconstituted with wild-type bone marrow-derived mast cells. Mast cell infiltration into the tumor microenvironment was predictive of poor prognosis in patients with PDAC.

CONCLUSIONS

Mast cells play an important role in PDAC growth and development in mouse models and are indicative of poor prognosis in humans, which makes them a potential novel therapeutic target.

The role of tumor stroma in cancer progression and prognosis: emphasis on carcinoma-associated fibroblasts and non-small cell lung cancer

Maintenance of both normal epithelial tissues and their malignant counterparts is supported by the host tissue stroma. The tumor stroma mainly consists of the basement membrane, fibroblasts, extracellular matrix, immune cells, and vasculature. Although most host cells in the stroma possess certain tumor-suppressing abilities, the stroma will change during malignancy and eventually promote growth, invasion, and metastasis. Stromal changes at the invasion front include the appearance of carcinoma-associated fibroblasts (CAFs). CAFs constitute a major portion of the reactive tumor stroma and play a crucial role in tumor progression. The main precursors of CAFs are normal fibroblasts, and the transdifferentiation of fibroblasts to CAFs is driven to a great extent by cancer-derived cytokines such as transforming growth factor-β. During recent years, the crosstalk between the cancer cells and the tumor stroma, highly responsible for the progression of tumors and their metastasis, has been increasingly unveiled. A better understanding of the host stroma contribution to cancer progression will increase our knowledge about the growth promoting signaling pathways and hopefully lead to novel therapeutic interventions targeting the tumor stroma. This review reports novel data on the essential crosstalk between cancer cells and cells of the tumor stroma, with an emphasis on the role played by CAFs. Furthermore, it presents recent literature on relevant tumor stroma- and CAF-related research in non-small cell lung cancer.

Role of versican, hyaluronan and CD44 in ovarian cancer metastasis

There is increasing evidence to suggest that extracellular matrix (ECM) components play an active role in tumor progression and are an important determinant for the growth and progression of solid tumors. Tumor cells interfere with the normal programming of ECM biosynthesis and can extensively modify the structure and composition of the matrix. In ovarian cancer alterations in the extracellular environment are critical for tumor initiation and progression and intra-peritoneal dissemination. ECM molecules including versican and hyaluronan (HA) which interacts with the HA receptor, CD44, have been shown to play critical roles in ovarian cancer metastasis. This review focuses on versican, HA, and CD44 and their potential as therapeutic targets for ovarian cancer.