The multifaceted role of periostin in priming the tumor microenvironments for tumor progression

The dual role of POSTN in maintaining glioblastoma stem cells and the immunosuppressive phenotype of microglia in glioblastoma

BACKGROUND

Glioblastoma (GBM) is an immunosuppressive, universally lethal cancer driven by glioblastoma stem cells (GSCs). The interplay between GSCs and immunosuppressive microglia plays crucial roles in promoting the malignant growth of GBM; however, the molecular mechanisms underlying this crosstalk are unclear. This study aimed to investigate the role of POSTN in maintaining GSCs and the immunosuppressive phenotype of microglia.

METHODS

The expression of POSTN in GBM was identified via immunohistochemistry, quantitative real-time PCR, and immunoblotting. Tumorsphere formation assay, Cell Counting Kit-8 assay and immunofluorescence were used to determine the key role of POSTN in GSC maintenance. ChIP-seq and ChIP-PCR were conducted to confirm the binding sequences of β-catenin in the promoter region of FOSL1. Transwell migration assays, developmental and functional analyses of CD4+ T cells, CFSE staining and analysis, enzyme-linked immunosorbent assays and apoptosis detection tests were used to determine the key role of POSTN in maintaining the immunosuppressive phenotype of microglia and thereby promoting the immunosuppressive tumor microenvironment. Furthermore, the effects of POSTN on GSC maintenance and the immunosuppressive phenotype of microglia were investigated in a patient-derived xenograft model and orthotopic glioma mouse model, respectively.

RESULTS

Our findings revealed that POSTN secreted from GSCs promotes GSC self-renewal and tumor growth via activation of the αVβ3/PI3K/AKT/β-catenin/FOSL1 pathway. In addition to its intrinsic effects on GSCs, POSTN can recruit microglia and upregulate CD70 expression in microglia through the αVβ3/PI3K/AKT/NFκB pathway, which in turn promotes Treg development and functionality and supports the formation of an immunosuppressive tumor microenvironment. In both in vitro models and orthotopic mouse models of GBM, POSTN depletion disrupted GSC maintenance, decreased the recruitment of immunosuppressive microglia and suppressed GBM growth.

CONCLUSION

Our findings reveal that POSTN plays critical roles in maintaining GSCs and the immunosuppressive phenotype of microglia and provide a new therapeutic target for treating GBM.

Cancer-associated fibroblast-derived periostin promotes papillary thyroid tumor growth through integrin-FAK-STAT3 signaling

Background: Periostin (POSTN) is a critical extracellular matrix protein in various tumor microenvironments. However, the function of POSTN in thyroid cancer progression remains largely unknown. Methods: Postn and Rag1 knock-out mice and orthotopic mouse models were used to determine the role of POSTN on papillary thyroid tumor progression. Immunofluorescence, cell co-culture, fluorescence in situ hybridization, chromatin immunoprecipitation assay, recombinant protein and inhibitor treatment were performed to explore the underlying mechanisms of POSTN-promoted papillary thyroid tumor growth. Results: POSTN is up-regulated in papillary thyroid tumors and negatively correlates with the overall survival of patients with thyroid cancer. Cancer-associated fibroblast (CAF)-derived POSTN promotes papillary thyroid tumor growth in vivo and in vitro. POSTN deficiency in CAFs significantly impairs CAF-promoted papillary thyroid tumor growth. POSTN promotes papillary thyroid tumor cell proliferation and IL-4 expression through integrin-FAK-STAT3 signaling. In turn, tumor cell-derived IL-4 induces the activation of CAFs and stimulates POSTN expression by activating STAT6. We reveal the crucial role of CAF-derived POSTN and tumor cell-derived IL-4 in driving the development of papillary thyroid tumors through the POSTN-integrin-FAK-STAT3-IL-4 pathway in tumor cells and IL-4-STAT6-POSTN signaling in CAFs. Conclusion: Our findings underscore the significance of POSTN and IL-4 as critical molecular mediators in the dynamic interplay between CAFs and tumor cells, ultimately supporting the growth of papillary thyroid tumors.

Tumor microenvironment of cancer stem cells: Perspectives on cancer stem cell targeting

There are few tumor cell subpopulations with stem cell characteristics in tumor tissue, defined as cancer stem cells (CSCs) or cancer stem-like cells (CSLCs), which can reconstruct neoplasms with malignant biological behaviors such as invasiveness via self-renewal and unlimited generation. The microenvironment that CSCs depend on consists of various cellular components and corresponding medium components. Among these factors existing at a variety of levels and forms, cytokine networks and numerous signal pathways play an important role in signaling transduction. These factors promote or maintain cancer cell stemness, and participate in cancer recurrence, metastasis, and resistance. This review aims to summarize the recent molecular data concerning the multilayered relationship between CSCs and CSC-favorable microenvironments. We also discuss the therapeutic implications of targeting this synergistic interplay, hoping to give an insight into targeting cancer cell stemness for tumor therapy and prognosis.

UTX inhibition suppresses proliferation and promotes apoptosis in patient-derived glioblastoma stem cells by modulating periostin expression

Glioblastoma stem cells (GSCs) exert a crucial influence on glioblastoma (GBM) development, progression, resistance to therapy, and recurrence, making them an attractive target for drug discovery. UTX, a histone H3K27 demethylase, participates in regulating multiple cancer types. However, its functional role in GSCs remains insufficiently explored. This study aims to investigate the role and regulatory mechanism of UTX on GSCs. Analysis of TCGA data revealed heightened UTX expression in glioma, inversely correlating with overall survival. Inhibiting UTX suppressed GBM cell growth and induced apoptosis. Subsequently, we cultured primary GSCs from three patients, observing that UTX inhibition suppressed cell proliferation and induced apoptosis. RNA-seq was performed to analyze the gene expression changes after silencing UTX in GSCs. The results indicated that UTX-mediated genes were strongly correlated with GBM progression and regulatory tumor microenvironment. The transwell co-cultured experiment showed that silencing UTX in the transwell chamber GSCs inhibited the well plate cell proliferation. Protein-protein interaction analysis revealed that periostin (POSTN) played a role in the UTX-mediated transcriptional regulatory network. Replenishing POSTN reversed the effects of UTX inhibition on GSC proliferation and apoptosis. Our study demonstrated that UTX inhibition hindered POSTN expression by enhancing the H3K27me2/3 level, eventually resulting in inhibiting proliferation and promoting apoptosis of patient-derived GSCs. Our findings may provide a novel and effective strategy for the treatment of GBM.

Single-cell and spatial transcriptomics reveal POSTN+ cancer-associated fibroblasts correlated with immune suppression and tumour progression in non-small cell lung cancer

BACKGROUND

Cancer-associated fibroblasts (CAFs) are potential targets for cancer therapy. Due to the heterogeneity of CAFs, the influence of CAF subpopulations on the progression of lung cancer is still unclear, which impedes the translational advances in targeting CAFs.

METHODS

We performed single-cell RNA sequencing (scRNA-seq) on tumour, paired tumour-adjacent, and normal samples from 16 non-small cell lung cancer (NSCLC) patients. CAF subpopulations were analyzed after integration with published NSCLC scRNA-seq data. SpaTial enhanced resolution omics-sequencing (Stereo-seq) was applied in tumour and tumour-adjacent samples from seven NSCLC patients to map the architecture of major cell populations in tumour microenvironment (TME). Immunohistochemistry (IHC) and multiplexed IHC (mIHC) were used to validate marker gene expression and the association of CAFs with immune infiltration in TME.

RESULTS

A subcluster of myofibroblastic CAFs, POSTN+ CAFs, were significantly enriched in advanced tumours and presented gene expression signatures related to extracellular matrix remodeling, tumour invasion pathways and immune suppression. Stereo-seq and mIHC demonstrated that POSTN+ CAFs were in close localization with SPP1+ macrophages and were associated with the exhausted phenotype and lower infiltration of T cells. POSTN expression or the abundance of POSTN+ CAFs were associated with poor prognosis of NSCLC.

CONCLUSIONS

Our study identified a myofibroblastic CAF subpopulation, POSTN+ CAFs, which might associate with SPP1+ macrophages to promote the formation of desmoplastic architecture and participate in immune suppression. Furthermore, we showed that POSTN+ CAFs associated with cancer progression and poor clinical outcomes and may provide new insights on the treatment of NSCLC.

Periostin secreted by cancer-associated fibroblasts promotes cancer progression and drug resistance in non-small cell lung cancer

Cancer-associated fibroblasts (CAFs) are important components in the tumor microenvironment, and we sought to identify effective therapeutic targets in CAFs for non-small cell lung cancer (NSCLC). In this study, we established fibroblast cell lines from the cancerous and non-cancerous parts of surgical lung specimens from patients with NSCLC and evaluated the differences in behaviors towards NSCLC cells. RNA sequencing analysis was performed to investigate the differentially expressed genes between normal fibroblasts (NFs) and CAFs, and we identified that the expression of periostin (POSTN), which is known to be overexpressed in various solid tumors and promote cancer progression, was significantly higher in CAFs than in NFs. POSTN increased cell proliferation via NSCLC cells' ERK pathway activation and induced epithelial-mesenchymal transition (EMT), which improved migration in vitro. In addition, POSTN knockdown in CAFs suppressed these effects, and in vivo experiments demonstrated that the POSTN knockdown improved the sensitivity of EGFR-mutant NSCLC cells for osimertinib treatment. Collectively, our results showed that CAF-derived POSTN is involved in tumor growth, migration, EMT induction, and drug resistance in NSCLC. Targeting CAF-secreted POSTN could be a potential therapeutic strategy for NSCLC. KEY MESSAGES: • POSTN is significantly upregulated in CAFs compared to normal fibroblasts in NCSLC. • POSTN increases cell proliferation via activation of the NSCLC cells' ERK pathway. • POSTN induces EMT in NSCLC cells and improves the migration ability. • POSTN knockdown improves the sensitivity for osimertinib in EGFR-mutant NSCLC cells.

Matrix stiffening facilitates the collective invasion of breast cancer through the periostin-integrin mechanotransduction pathway

Matrix rigidity is a critical contributor to tumor progression; however, whether and how matrix stiffness modulates the collective invasion of tumor cells remain unknown. Here we demonstrate that increased matrix stiffness activates YAP to promote the secretion of periostin (POSTN) in cancer-associated fibroblasts, which in turn augments the matrix rigidity of mammary glands and breast tumor tissues by facilitating collagen crosslinking. Moreover, decreased tissue stiffening resulted from the POSTN deficiency impairs peritoneal metastatic potential of orthotopic breast tumors. Increased matrix stiffness also promotes three-dimensional (3D) collective breast tumor cell invasion via multicellular cytoskeleton remodeling. POSTN triggers the integrin/FAK/ERK/Cdc42/Rac1 mechanotransduction pathway during 3D collective invasion of breast tumor. Clinically, high POSTN expression correlates with high collagen levels in breast tumors and cooperatively determines the metastatic recurrence potential in breast cancer patients. Collectively, these findings indicate that matrix rigidity promotes 3D collective invasion of breast tumor cells via the YAP-POSTN-integrin mechanotransduction signaling.

The functional role and the clinical application of periostin in chronic rhinosinusitis

INTRODUCTION

Chronic rhinosinusitis (CRS) comprises several heterogenous groups, now classified based on endotype more often than on phenotype. A number of studies aimed at finding a useful biomarker for type 2 CRS suggest that periostin is a promising surrogate.

AREAS COVERED

A comprehensive overview of the clinical significance of tissue periostin expression and serum periostin in CRS patients is provided. The effects of comorbid asthma on serum periostin and samples other than serum in which periostin can be detected in CRS patients are also discussed. Moreover, the functional roles of periostin in CRS pathogenesis are summarized.

EXPERT OPINION

The position of periostin as a signature biomarker of type 2 CRS has been well established, enabling us to classify CRS patients by endotyping. Serum periostin is useful not only for endotyping CRS patients, but also for estimating disease severity, comorbidity, prognosis, and response to treatment, and in particular, predicting recurrence after surgery. However, it remains to be addressed how we apply serum periostin to using biologics for CRS patients. Further studies aimed at showing periostin to be a therapeutic target for CRS are awaited.

Weaving the nest: extracellular matrix roles in pre-metastatic niche formation

The discovery that primary tumors condition distant organ sites of future metastasis for seeding by disseminating tumor cells through a process described as the pre-metastatic niche (PMN) formation revolutionized our understanding of cancer progression and opened new avenues for therapeutic interventions. Given the inherent inefficiency of metastasis, PMN generation is crucial to ensure the survival of rare tumor cells in the otherwise hostile environments of metastatic organs. Early on, it was recognized that preparing the "soil" of the distal organ to support the outgrowth of metastatic cells is the initiating event in PMN development, achieved through the remodeling of the organ's extracellular matrix (ECM). Remote restructuring of ECM at future sites of metastasis under the influence of primary tumor-secreted factors is an iterative process orchestrated through the crosstalk between resident stromal cells, such as fibroblasts, epithelial and endothelial cells, and recruited innate immune cells. In this review, we will explore the ECM changes, cellular effectors, and the mechanisms of ECM remodeling throughout PMN progression, as well as its impact on shaping the PMN and ultimately promoting metastasis. Moreover, we highlight the clinical and translational implications of PMN ECM changes and opportunities for therapeutically targeting the ECM to hinder PMN formation.

Reciprocal Regulation of Cancer-Associated Fibroblasts and Tumor Microenvironment in Gastrointestinal Cancer: Implications for Cancer Dormancy

Gastrointestinal (GI) cancers remain a major cause of cancer-related deaths worldwide. Despite the progress made in current treatments, patients with GI cancers still have high recurrence rates after initial treatment. Cancer dormancy, which involves the entry and escape of cancer cells from dormancy, is linked to treatment resistance, metastasis, and disease relapse. Recently, the role of the tumor microenvironment (TME) in disease progression and treatment has received increasing attention. The crosstalk between cancer-associated fibroblasts (CAF)-secreted cytokines/chemokines and other TME components, for example, extracellular matrix remodeling and immunomodulatory functions, play crucial roles in tumorigenesis. While there is limited direct evidence of a relationship between CAFs and cancer cell dormancy, this review explores the potential of CAF-secreted cytokines/chemokines to either promote cancer cell dormancy or awaken dormant cancer cells under different conditions, and the therapeutic strategies that may be applicable. By understanding the interactions between cytokines/chemokines released by CAFs and the TME, and their impact on the entry/escape of cancer dormancy, researchers may develop new strategies to reduce the risk of therapeutic relapse in patients with GI cancers.

Targeting TGF-β/periostin signaling by sesamol ameliorates pulmonary fibrosis and improves lung function and survival

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive disorder that severely impairs lung function, by increasing lung stiffness. Sesamol, a phenolic Phyto-molecule isolated from sesame seeds, possess a rich source of protein and is known to have extensive nutritional and health effects. Here we investigated the effect of sesamol on TGF-β/periostin-induced fibroblast differentiation in in vitro and bleomycin-induced pulmonary fibrosis in an in vivo model. Our results demonstrated that activation of (DHLF, LL29, NHLF and A549) cells with TGF-β, elevates the epithelial to mesenchymal, extracellular matrix, and collagen deposition and periostin signaling marker's expression, further treatment with sesamol attenuated these markers significantly. In addition, sesamol treatment improved the TGF-β-induced contraction and migration of cells. Mechanistic studies showed that activation of IPF cells with periostin increased the TGF-β signaling and treatment with sesamol significantly abrogated the periostin-induced TGF-β activation and its downstream fibrotic marker's expression. In in vivo, sesamol treatment attenuated the lung inflammation, infiltration of cells, wall thickening and the formation of fibrous bands significantly in BLM-induced fibrosis rats. Molecular studies revealed that sesamol treatment reduced the bleomycin-induced fibrotic, inflammatory, apoptotic marker's expression by modulating the TGF-β/periostin crosstalk signaling in a dose-dependent manner. Further, treatment with sesamol dramatically improved lung function and decreased mortality. Our study first time reports the sesamol's inhibitory effects on periostin signalling. Collectively, our study demonstrated that periostin and TGF-β seem to work in a positive-feedback loop, inducing the other, therefore, targeting TGF-β/periostin signaling may provide a better therapeutic approach against IPF and other fibrotic disorders.

Periostin Protects Against Alcohol-related Liver Disease by Activating Autophagy by Interacting With Protein Disulfide Isomerase

BACKGROUND & AIMS

The matricellular protein periostin plays a critical role in liver inflammation, fibrosis, and even carcinoma. Here, the biological function of periostin in alcohol-related liver disease (ALD) was investigated.

METHODS

We used wild-type (WT), Postn-null (Postn^-/-) mice and Postn^-/- mice with periostin recovery to investigate the biological function of periostin in ALD. Proximity-dependent biotin identification analysis identified the protein that interacted with periostin, and coimmunoprecipitation analysis validated the interaction between protein disulfide isomerase (PDI) and periostin. Pharmacological intervention and genetic knockdown of PDI were used to investigate the functional correlation between periostin and PDI in ALD development.

RESULTS

Periostin was markedly upregulated in the livers of mice that were fed ethanol. Interestingly, periostin deficiency severely aggravated ALD in mice, whereas the recovery of periostin in the livers of Postn^-/- mice significantly ameliorated ALD. Mechanistic studies showed that the upregulation of periostin alleviated ALD by activating autophagy through inhibition of the mechanistic target of rapamycin complex 1 (mTORC1) pathway, which was verified in murine models treated with the mTOR inhibitor rapamycin and the autophagy inhibitor MHY1485. Furthermore, a protein interaction map of periostin was generated by proximity-dependent biotin identification analysis. Interaction profile analysis identified PDI as a key protein that interacted with periostin. Intriguingly, periostin-mediated enhancement of autophagy by inhibiting the mTORC1 pathway in ALD depended on its interaction with PDI. Moreover, alcohol-induced periostin overexpression was regulated by transcription factor EB.

CONCLUSIONS

Collectively, these findings clarify a novel biological function and mechanism of periostin in ALD and the periostin-PDI-mTORC1 axis is a critical determinant of ALD.

Association between serum periostin levels and the severity of arsenic-induced skin lesions

Arsenic is a potent environmental toxicant and human carcinogen. Skin lesions are the most common manifestations of chronic exposure to arsenic. Advanced-stage skin lesions, particularly hyperkeratosis have been recognized as precancerous diseases. However, the underlying mechanism of arsenic-induced skin lesions remains unknown. Periostin, a matricellular protein, is implicated in the pathogenesis of many forms of skin lesions. The objective of this study was to examine whether periostin is associated with arsenic-induced skin lesions. A total of 442 individuals from low- (n = 123) and high-arsenic exposure areas (n = 319) in rural Bangladesh were evaluated for the presence of arsenic-induced skin lesions (Yes/No). Participants with skin lesions were further categorized into two groups: early-stage skin lesions (melanosis and keratosis) and advanced-stage skin lesions (hyperkeratosis). Drinking water, hair, and nail arsenic concentrations were considered as the participants' exposure levels. The higher levels of arsenic and serum periostin were significantly associated with skin lesions. Causal mediation analysis revealed the significant effect of arsenic on skin lesions through the mediator, periostin, suggesting that periostin contributes to the development of skin lesions. When skin lesion was used as a three-category outcome (none, early-stage, and advanced-stage skin lesions), higher serum periostin levels were significantly associated with both early-stage and advanced-stage skin lesions. Median (IQR) periostin levels were progressively increased with the increasing severity of skin lesions. Furthermore, there were general trends in increasing serum type 2 cytokines (IL-4, IL-5, IL-13, and eotaxin) and immunoglobulin E (IgE) levels with the progression of the disease. The median (IQR) of IL-4, IL-5, IL-13, eotaxin, and IgE levels were significantly higher in the early-and advanced-stage skin lesions compared to the group of participants without skin lesions. The results of this study suggest that periostin is implicated in the pathogenesis and progression of arsenic-induced skin lesions through the dysregulation of type 2 immune response.

Periostin as a Biomarker in the Setting of Glomerular Diseases-A Review of the Current Literature

Chronic kidney disease (CKD) is a highly prevalent and potential progressive condition with life-threatening consequences. Glomerular diseases (glomerulopathies) are causes of CKD that are potentially amenable by specific therapies. Significant resources have been invested in the identification of novel biomarkers of CKD progression and new targets for treatment. By using experimental models of kidney diseases, periostin has been identified amongst the most represented matricellular proteins that are commonly involved in the inflammation and fibrosis that characterize progressive kidney diseases. Periostin is highly expressed during organogenesis, with scarce expression in mature healthy tissues, but it is upregulated in multiple disease settings characterized by tissue injury and remodeling. Periostin was the most highly expressed matriceal protein in both animal models and in patients with glomerulopathies. Given that periostin is readily secreted from injury sites, and the variations in its humoral levels compared to the normal state were easily detectable, its potential role as a biomarker is suggested. Moreover, periostin expression was correlated with the degree of histological damage and with kidney function decline in patients with CKD secondary to both inflammatory (IgA nephropathy) and non-inflammatory (membranous nephropathy) glomerulopathies, while also displaying variability secondary to treatment response. The scope of this review is to summarize the existing evidence that supports the role of periostin as a novel biomarker in glomerulopathies.

Periostin- and podoplanin-positive cancer-associated fibroblast subtypes cooperate to shape the inflamed tumor microenvironment in aggressive pancreatic adenocarcinoma

Cancer-associated fibroblasts (CAFs) are orchestrators of the pancreatic ductal adenocarcinoma (PDAC) microenvironment. Previously we described four CAF subtypes with specific molecular and functional features. Here, we have refined our CAF subtype signatures using RNAseq and immunostaining with the goal of defining bioinformatically the phenotypic stromal and tumor epithelial states associated with CAF diversity. We used primary CAF cultures grown from patient PDAC tumors, human data sets (in-house and public, including single-cell analyses), genetically engineered mouse PDAC tissues, and patient-derived xenografts (PDX) grown in mice. We found that CAF subtype RNAseq signatures correlated with immunostaining. Tumors rich in periostin-positive CAFs were significantly associated with shorter overall survival of patients. Periostin-positive CAFs were characterized by high proliferation and protein synthesis rates and low α-smooth muscle actin expression and were found in peri-/pre-tumoral areas. They were associated with highly cellular tumors and with macrophage infiltrates. Podoplanin-positive CAFs were associated with immune-related signatures and recruitment of dendritic cells. Importantly, we showed that the combination of periostin-positive CAFs and podoplanin-positive CAFs was associated with specific tumor microenvironment features in terms of stromal abundance and immune cell infiltrates. Podoplanin-positive CAFs identified an inflammatory CAF (iCAF)-like subset, whereas periostin-positive CAFs were not correlated with the published myofibroblastic CAF (myCAF)/iCAF classification. Taken together, these results suggest that a periostin-positive CAF is an early, activated CAF, associated with aggressive tumors, whereas a podoplanin-positive CAF is associated with an immune-related phenotype. These two subpopulations cooperate to define specific tumor microenvironment and patient prognosis and are of putative interest for future therapeutic stratification of patients. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Role of the Hypoxic-Secretome in Seed and Soil Metastatic Preparation

During tumor growth, the delivery of oxygen to cells is impaired due to aberrant or absent vasculature. This causes an adaptative response that activates the expression of genes that control several essential processes, such as glycolysis, neovascularization, immune suppression, and the cancer stemness phenotype, leading to increased metastasis and resistance to therapy. Hypoxic tumor cells also respond to an altered hypoxic microenvironment by secreting vesicles, factors, cytokines and nucleic acids that modify not only the immediate microenvironment but also organs at distant sites, allowing or facilitating the attachment and growth of tumor cells and contributing to metastasis. Hypoxia induces the release of molecules of different biochemical natures, either secreted or inside extracellular vesicles, and both tumor cells and stromal cells are involved in this process. The mechanisms by which these signals that can modify the premetastatic niche are sent from the primary tumor site include changes in the extracellular matrix, recruitment and activation of different stromal cells and immune or nonimmune cells, metabolic reprogramming, and molecular signaling network rewiring. In this review, we will discuss how hypoxia might alter the premetastatic niche through different signaling molecules.

Potential of the Stromal Matricellular Protein Periostin as a Biomarker to Improve Risk Assessment in Prostate Cancer

Prostate cancer (PCa) ranges from indolent to aggressive tumors that may rapidly progress and metastasize. The switch to aggressive PCa is fostered by reactive stroma infiltrating tumor foci. Therefore, reactive stroma-based biomarkers may potentially improve the early detection of aggressive PCa, ameliorating disease classification. Gene expression profiles of PCa reactive fibroblasts highlighted the up-regulation of genes related to stroma deposition, including periostin and sparc. Here, the potential of periostin as a stromal biomarker has been investigated on PCa prostatectomies by immunohistochemistry. Moreover, circulating levels of periostin and sparc have been assessed in a low-risk PCa patient cohort enrolled in active surveillance (AS) by ELISA. We found that periostin is mainly expressed in the peritumoral stroma of prostatectomies, and its stromal expression correlates with PCa grade and aggressive disease features, such as the cribriform growth. Moreover, stromal periostin staining is associated with a shorter biochemical recurrence-free survival of PCa patients. Interestingly, the integration of periostin and sparc circulating levels into a model based on standard clinico-pathological variables improves its performance in predicting disease reclassification of AS patients. In this study, we provide the first evidence that circulating molecular biomarkers of PCa stroma may refine risk assessment and predict the reclassification of AS patients.

Elevated serum periostin levels among arsenic-exposed individuals and their associations with the features of asthma

Chronic exposure to arsenic via drinking water is a serious public health issue in many countries. Arsenic causes not only cancers but also non-malignant diseases, including asthma. We have previously reported that arsenic exposure increases the risk of Th2-mediated allergic asthma. The serum level of periostin, an extracellular matrix protein activated by Th2 cytokines, is recognized as a biomarker for Th2-mediated eosinophilic asthma and contributes to enhanced airway inflammation and remodeling. However, the role of periostin in arsenic-related asthma is unknown. Therefore, this study was designed to explore the associations of serum periostin levels with arsenic exposure and the features of asthma in 442 individuals in Bangladesh who participated in our previous study. Exposure levels of the participants were determined by measuring the arsenic concentrations in drinking water, hair, and nails through inductively coupled plasma mass spectroscopy. Periostin levels in serum were assessed by immunoassay. In this study, we found that serum periostin levels of the participants were increased with increasing exposure to arsenic. Notably, even the participants with 10.1-50 μg/L arsenic in drinking water had significantly higher levels of periostin than participants with <10 μg/L of water arsenic. Elevated serum periostin levels were positively associated with serum levels of Th2 mediators, such as interleukin (IL)-4, IL-5, IL-13, and eotaxin. Each log increase in periostin levels was associated with approximately eight- and three-fold increases in the odds ratios (ORs) for reversible airway obstruction (RAO) and asthma symptoms, respectively. Additionally, causal mediation analyses revealed that arsenic exposure metrics had both direct and indirect (periostin-mediated) effects on the risk of RAO and asthma symptoms. Thus, the results suggested that periostin may be involved in the arsenic-related pathogenesis of Th2-mediated asthma. The elevated serum periostin levels may predict the greater risk of asthma among the people living in arsenic-endemic areas.

Establishment of a novel ELISA system for measuring periostin independently of formation of the IgA complex

BACKGROUND

Periostin, a matricellular protein that modulates cell functions having various pathophysiological roles, has the potential to be a useful biomarker for various diseases. We recently found that periostin forms a complex with IgA in human serum, which may affect the periostin measurement.

METHODS

We investigated (1) whether the formation of the periostin-IgA complex affects the original periostin ELISA system, decreasing the values of serum periostin? (2) bow each domain of periostin affects periostin measurement by the original periostin ELISA system? (3) whether we can establish a novel ELISA system that is not affected by formation of the IgA complex?

RESULTS

The periostin value at the reducing condition was significantly higher than that of the non-reducing condition, demonstrating that formation of the IgA complex affects periostin measurement. The monoclonal antibodies (mAbs) for periostin recognizing the EMI and R1 domains immunoprecipitated serum periostin in the reducing condition more than in the non-reducing condition, whereas the mAbs recognizing the R2 or R3 domain immunoprecipitated comparable amounts of serum periostin in the reducing and non-reducing conditions, suggesting the EMI and R1 domains contribute to formation of the complex with IgA. Using SS16A recognizing the R3 domain combined with SS17B recognizing the R4 domain, we established an ELISA system that was able to measure periostin independently of the IgA complex.

CONCLUSIONS

We have established a novel ELISA system that measures periostin independently of the IgA complex. This system is promising in identifying periostin as a biomarker for various diseases.

Genome Instability-Associated Long Non-Coding RNAs Reveal Biomarkers for Glioma Immunotherapy and Prognosis

Genome instability is a hallmark of tumors and is involved in proliferation, invasion, migration, and treatment resistance of many tumors. However, the relationship of genome instability with gliomas remains unclear. Here, we constructed genome instability-derived long non-coding RNA (lncRNA)-based gene signatures (GILncSig) using genome instability-related lncRNAs derived from somatic mutations. Multiple platforms were used to confirm that the GILncSig were closely related to patient prognosis and clinical characteristics. We found that GILncSig, the glioma microenvironment, and glioma cell DNA methylation-based stemness index (mDNAsi) interacted with each other to form a complex regulatory network. In summary, this study confirmed that GILncSig was an independent prognostic indicator for patients, distinguished high-risk and low-risk groups, and affected immune-cell infiltration and tumor-cell stemness indicators (mDNAsi) in the tumor microenvironment, resulting in tumor heterogeneity and immunotherapy resistance. GILncSig are expected to provide new molecular targets for the clinical treatment of patients with gliomas.

Periostin in lymph node pre-metastatic niches governs lymphatic endothelial cell functions and metastatic colonization

Although lymph node (LN) metastasis is an important prognostic parameter in cervical cancer, the tissue remodeling at a pre-metastatic state is poorly documented in LNs. We here identified periostin (POSTN) as a component of non-metastatic LNs by applying proteomic analyses and computerized image quantifications on LNs of patients with cervical cancer. We provide evidence for remarkable modifications of POSTN and lymphatic vessel distributions and densities in non-metastatic sentinel and metastatic human LNs, when compared to distant non-metastatic LNs. POSTN deposition at a pre-metastatic stage was demonstrated in a pre-clinical murine model (the ear sponge assay). Its expression by fibroblastic LN cells was assessed by in situ hybridization and in vitro cultures. In vitro, POSTN promoted lymphatic endothelial cell functions and tumor cell proliferation. Accordingly, the in vivo injection of recombinant POSTN together with VEGF-C boosted the lymphangiogenic response, while the metastatic potential of tumor cells was drastically reduced using a POSTN blocking antibody. This translational study also supports the existence of an unprecedented dialog “in cascade”, between the primary tumor and the first pelvic nodal relay in early cervical cancer, and subsequently from pelvic LN to para-aortic LNs in locally advanced cervical cancers. Collectively, this work highlights the association of POSTN deposition with lymphangiogenesis in LNs, and provides evidence for a key contribution of POSTN in promoting VEGF-C driven lymphangiogenesis and the seeding of metastatic cells.

miRNAs-mediated overexpression of Periostin is correlated with poor prognosis and immune infiltration in lung squamous cell carcinoma

Lung cancer is one of the most common malignancies with a high mortality rate worldwide. POSTN has been shown to be strongly correlated with the poor prognosis of lung cancer patients. However, the function and mechanism of action of POSTN in lung cancer remain unclear. Here, we carried out a pan-cancer analysis to assess the clinical prognostic value of POSTN based on the TCGA, TIMER, Oncomine, Kaplan-Meier, and UALCAN databases. We found that upregulated POSTN can be a promising biomarker to predict the prognosis of patients with lung cancer. High levels of POSTN correlated with immune cell infiltration in lung cancer, especially lung squamous cell carcinoma (LUSC), which was further confirmed based on the results from the TISIDB database. Moreover, the expression analysis, correlation analysis, and survival analysis revealed that POSTN-targeted miRNAs, downregulation of has-miR-144-3p and has-miR-30e-3p, were significantly linked to poor prognosis in patients with LUSC. Taken together, we identified that POSTN can act as a novel biomarker for determining the prognosis related to immune infiltration in patients with LUSC and deserves further research.

The extracellular matrix of hematopoietic stem cell niches

•

Comprehensive overview of different classes of ECM molecules in the HSC niche.

•

Overview of current knowledge on role of biophysics of the HSC niche.

•

Description of approaches to create artificial stem cell niches for several application.

•

Importance of considering ECM in drug development and testing.

Hematopoietic stem cells (HSCs) are the life-long source of all types of blood cells. Their function is controlled by their direct microenvironment, the HSC niche in the bone marrow. Although the importance of the extracellular matrix (ECM) in the niche by orchestrating niche architecture and cellular function is widely acknowledged, it is still underexplored. In this review, we provide a comprehensive overview of the ECM in HSC niches. For this purpose, we first briefly outline HSC niche biology and then review the role of the different classes of ECM molecules in the niche one by one and how they are perceived by cells. Matrix remodeling and the emerging importance of biophysics in HSC niche function are discussed. Finally, the application of the current knowledge of ECM in the niche in form of artificial HSC niches for HSC expansion or targeted differentiation as well as drug testing is reviewed.

Diagnostic value of periostin in lung cancer-related malignant pleural effusion

BACKGROUND

Periostin (POSTN) is an extracellular matrix protein that is overexpressed in lung cancer and is considered an effective diagnostic and prognostic biomarker for lung cancer. The purpose of this study was to investigate the diagnostic performance of POSTN and to further evaluate the diagnostic value of POSTN combined with carcinoembryonic antigen (CEA) and cancer ratio [CR: serum lactate dehydrogenase (LDH)/pleural effusion adenosine deaminase (PE ADA)] in lung cancer-related malignant PE (MPE).

METHODS

A total of 108 patients with PE, including 54 with lung cancer and 54 with benign lung disease, were enrolled in this study. The POSTN levels of PE and serum were detected using an enzyme-linked immunosorbent assay. Information on the expression of PE and serum CEA, serum LDH, and PE ADA was collected from medical records.

RESULTS

The levels of PE POSTN in MPE of patients with lung cancer were significantly higher than those in patients with benign PE (p < 0.0001). The receiver operating characteristic (ROC) curve indicated that the diagnostic sensitivity and specificity of PE POSTN for lung cancer-related MPE were respectively 77.78% and 68.52% when the cutoff value was determined to be 53.45 ng/ml. The ROC curve analysis demonstrated that PE POSTN has a high diagnostic value in MPE associated with lung cancer [area under the curve (AUC) = 0.764], and the combination of PE POSTN, PE CEA, and CR can improve the diagnostic accuracy of lung cancer-related MPE (AUC = 0.948).

CONCLUSION

POSTN can be used as a potential marker for lung cancer-related MPE diagnosis.

Periostin secreted by activated fibroblasts in idiopathic pulmonary fibrosis promotes tumorigenesis of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) patients with idiopathic pulmonary fibrosis (IPF) show poor prognosis. Periostin is an extracellular matrix protein highly expressed in the lung tissues of IPF. This study aimed to investigate the possibility that periostin secreted by fibroblasts derived from IPF lung might affect proliferation of NSCLC cells. Periostin was more highly expressed and secreted by fibroblasts from diseased human lung with IPF (DIPF) than by normal human lung fibroblasts (NHLF). Cocultivation of NSCLC cells with conditioned media (CM) from DIPF increased proliferation of NSCLC cells through pErk signaling, with this proliferation attenuated by periostin-neutralizing antibodies. Knockdown of integrin β3, a subunit of the periostin receptor, in NSCLC cells suppressed proliferation of NSCLC cells promoted by recombinant human periostin and CM of DIPF. On in vivo examination, DIPF promoted tumor progression more than NHLF, and knockdown of integrin β3 in NSCLC cells suppressed tumor progression promoted by DIPF. Fibroblasts derived from surgical specimens from IPF patients also increased secretion of periostin compared to those from non-IPF patients. Periostin secreted from IPF-activated fibroblasts plays critical roles in the proliferation of NSCLC cells. The present study provides a solid basis for considering periostin-targeted therapy for NSCLC patients with IPF.

Periostin deficiency reduces diethylnitrosamine-induced liver cancer in mice by decreasing hepatic stellate cell activation and cancer cell proliferation

Periostin is a critical extracellular regulator in the pathogenesis of liver disorders such as hepatosteatosis, non-alcoholic steatohepatitis, inflammation, and fibrosis. Periostin is also involved in the progression of hepatocellular carcinoma (HCC). However, the molecular mechanisms of periostin in hepatic stellate cell (HSC) activation and tumor cell proliferation in the pathogenesis of HCC remain largely unknown. We demonstrate that periostin is markedly upregulated in diethylnitrosamine (DEN)-induced mouse HCC tissues and that periostin knockout impairs DEN-induced HCC development. Periostin is predominantly derived from activated HSCs and periostin deficiency in HSCs impairs HSC activation and inhibits HSC-promoted HCC cell proliferation in vitro and tumor growth in vivo. Mechanistically, periostin promotes HSC activation through the integrin-FAK-STAT3-periostin pathway and augments HCC cell proliferation by activating ERK. There are positive correlations between periostin and HSC activation and cell proliferation in HCC clinical samples. Collectively, our findings demonstrate that HSC-derived periostin promotes HCC development by enhancing HSC activation through an autocrine periostin-integrin-FAK-STAT3-periostin circuit and by augmenting HCC cell proliferation via the ERK pathway in a paracrine manner. Thus, periostin is a multifaceted extracellular regulator in the development of HCC. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

A positive feedback loop between Periostin and TGFβ1 induces and maintains the stemness of hepatocellular carcinoma cells via AP-2α activation

Background

Liver cancer stem cells (LCSCs) play key roles in the metastasis, recurrence, and chemotherapeutic resistance of hepatocellular carcinoma (HCC). Our previous research showed that the POSTN gene is closely related to the malignant progression and poor prognosis of HCC. This study aimed to elucidate the role of POSTN in generating LCSCs and maintaining their stemness as well as the underlying mechanisms.

Methods

Human HCC tissues and matched adjacent normal tissues were obtained from 110 patients. Immunohistochemistry, western blotting (WB), and RT-PCR were performed to detect the expression of POSTN and stemness factors. The roles of transforming growth factor (TGF)-β1 and AP-2α in the POSTN-induced stemness transformation of HCC cells were explored in vitro and in vivo using LCSCs obtained by CD133⁺ cell sorting.

Results

The high expression of POSTN was correlated with the expression of various stemness factors, particularly CD133, in our HCC patient cohort and in TCGA and ICGC datasets. Knockdown of POSTN expression decreased the abilities of HCC cell lines to form tumours in xenograft mouse models. Knockdown of POSTN expression also suppressed cell viability and clone formation, invasion, and sphere formation abilities in vitro. Knockdown of AP-2α attenuated the generation of CD133⁺ LCSCs and their malignant behaviours, indicating that AP-2α was a critical factor that mediated the POSTN-induced stemness transformation and maintenance of HCC cells. The role of AP-2α was verified by using a specific αvβ3 antagonist, cilengitide, in vitro and in vivo. Activation of POSTN could release TGFβ1 from the extracellular matrix and initiated POSTN/TGFβ1 positive feedback signalling. Furthermore, we found that the combined use of cilengitide and lenvatinib suppressed the growth of HCC cells with high POSTN expression more effectively than the use of lenvatinib alone in the patient-derived xenograft (PDX) mouse model.

Conclusions

The POSTN/TGFβ1 positive feedback pathway regulates the expression of stemness factors and the malignant progression of HCC cells by regulating the transcriptional activation of AP-2α. This pathway may serve as a new target for targeted gene therapy in HCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02011-8.

Functions of Matricellular Proteins in Dental Tissues and Their Emerging Roles in Orofacial Tissue Development, Maintenance, and Disease

Matricellular proteins (MCPs) are defined as extracellular matrix (ECM) associated proteins that are important regulators and integrators of microenvironmental signals, contributing to the dynamic nature of ECM signalling. There is a growing understanding of the role of matricellular proteins in cellular processes governing tissue development as well as in disease pathogenesis. In this review, the expression and functions of different MP family members (periostin, CCNs, TSPs, SIBLINGs and others) are presented, specifically in relation to craniofacial development and the maintenance of orofacial tissues, including bone, gingiva, oral mucosa, palate and the dental pulp. As will be discussed, each MP family member has been shown to have non-redundant roles in development, tissue homeostasis, wound healing, pathology and tumorigenesis of orofacial and dental tissues.

An Immune Gene-Related Five-lncRNA Signature for to Predict Glioma Prognosis

Background

The tumor immune microenvironment is closely related to the malignant progression and treatment resistance of glioma. Long non-coding RNA (lncRNA) plays a regulatory role in this process. We investigated the pathological mechanisms within the glioma microenvironment and potential immunotherapy resistance related to lncRNAs.

Method

We downloaded datasets derived from glioma patients and analyzed them by hierarchical clustering. Next, we analyzed the immune microenvironment of glioma, related gene expression, and patient survival. Coexpressed lncRNAs were analyzed to generate a model of lncRNAs and immune-related genes. We analyzed the model using survival and Cox regression. Then, univariate, multivariate, receiver operating characteristic (ROC), and principle component analysis (PCA) methods were used to verify the accuracy of the model. Finally, GSEA was used to evaluate which functions and pathways were associated with the differential genes.

Results

Normal brain tissue maintains a low-medium immune state, and gliomas are clearly divided into three groups (low to high immunity). The stromal, immune, and estimate scores increased along with immunity, while tumor purity decreased. Further, human leukocyte antigen (HLA), programmed cell death-1 (PDL1), T cell immunoglobulin and mucin domain 3 (TIM-3), B7-H3, and cytotoxic T lymphocyte-associated antigen-4 (CTLA4) expression increases concomitantly with immune state, and the patient prognosis worsens. Five immune gene-related lncRNAs (AP001007.1, LBX-AS1, MIR155HG, MAPT-AS1, and LINC00515) were screened to construct risk models. We found that risk scores are related to patient prognosis and clinical characteristics, and are positively correlated with PDL1, TIM-3, and B7-H3 expression. These lncRNAs may regulate the tumor immune microenvironment through cytokine-cytokine receptor interactions, complement, and coagulation cascades, and may promote CD8 + T cell, regulatory T cell, M1 macrophage, and infiltrating neutrophils activity in the high-immunity group. In vitro, the abnormal expression of immune-related lncRNAs and the relationship between risk scores and immune-related indicators (PDL1, CTLA4, CD3, CD8, iNOS) were verified by q-PCR and immunohistochemistry (IHC).

Conclusion

For the first time, we constructed immune gene-related lncRNA risk models. The risk score may be a new biomarker for tumor immune subtypes and provide molecular targets for glioma immunotherapy.

The extracellular matrix: A key player in the pathogenesis of hematologic malignancies

Hematopoietic stem and progenitor cells located in the bone marrow lay the foundation for multiple lineages of mature hematologic cells. Bone marrow niches are architecturally complex with specific cellular, physiochemical, and biomechanical factors. Increasing evidence suggests that the bone marrow microenvironment contributes to the pathogenesis of hematological neoplasms. Numerous studies have deciphered the role of genetic mutations and chromosomal translocations in the development hematologic malignancies. Significant progress has also been made in understanding how the cellular components and cytokine interactions within the bone marrow microenvironment promote the evolution of hematologic cancers. Although the extracellular matrix is known to be a key player in the pathogenesis of various diseases, it's role in the progression of hematologic malignancies is less understood. In this review, we discuss the interactions between the extracellular matrix and malignant cells, and provide an overview of the role of extracellular matrix remodeling in sustaining hematologic malignancies.

Periostin+ cancer-associated fibroblasts promote lymph node metastasis by impairing the lymphatic endothelial barriers in cervical squamous cell carcinoma

Lymph node metastasis (LNM), a critical prognostic determinant in cancer patients, is critically influenced by the presence of numerous heterogeneous cancer‐associated fibroblasts (CAFs) in the tumor microenvironment. However, the phenotypes and characteristics of the various pro‐metastatic CAF subsets in cervical squamous cell carcinoma (CSCC) remain unknown. Here, we describe a CAF subpopulation with elevated periostin expression (periostin⁺CAFs), located in the primary tumor sites and metastatic lymph nodes, that positively correlated with LNM and poor survival in CSCC patients. Mechanistically, periostin⁺CAFs impaired lymphatic endothelial barriers by activating the integrin‐FAK/Src‐VE‐cadherin signaling pathway in lymphatic endothelial cells and consequently enhanced metastatic dissemination. In contrast, inhibition of the FAK/Src signaling pathway alleviated periostin‐induced lymphatic endothelial barrier dysfunction and its related effects. Notably, periostin^‐CAFs were incapable of impairing endothelial barrier integrity, which may explain the occurrence of CAF‐enriched cases without LNM. In conclusion, we identified a specific periostin⁺CAF subset that promotes LNM in CSCC, mainly by impairing the lymphatic endothelial barriers, thus providing the basis for potential stromal fibroblast‐targeted interventions that block CAF‐dependent metastasis.

Prognostic Significance of Stromal Periostin Expression in Non-Small Cell Lung Cancer

Background: The microenvironment of solid tumours is significant in cancer development and progression. The aim of this study was to determine periostin (POSTN) expression by cancer-associated fibroblasts (CAFs) in non-small-cell lung cancer (NSCLC), as well as to assess associations with clinicopathological factors and prognosis. Materials and Methods: Immunohistochemical analysis of POSTN expression was performed on NSCLC (N = 700) and non-malignant lung tissue (NMLT) (N = 110) using tissue microarrays. Laser capture microdissection (LCM) for isolation of stromal and cancer cells of NSCLC was employed, and subsequently, POSTN mRNA expression was detected by real-time PCR. Immunofluorescence reaction and colocalisation analysis were performed by confocal microscopy. Results: Expression of POSTN in CAFs was significantly higher in NSCLC and in the adenocarcinoma (AC) and squamous cell carcinoma (SCC) subtypes compared to NMLT. POSTN expression in CAFs increased with clinical cancer stage, grades (G) of malignancy, and lymph node involvement in NSCLC. Higher POSTN expression in CAFs was an independent prognostic factor for overall survival (OS). LCM confirmed significantly higher POSTN mRNA expression in the stromal cells (CAFs) compared to the lung cancer cells. Conclusions: POSTN produced by CAFs might be crucial for NSCLC progression and can be an independent negative prognostic factor in NSCLC.

Integrative Analysis of Periostin in Primary and Advanced Prostate Cancer

Periostin (POSTN) is an extracellular matrix protein associated with tumor progression and shorter survival in prostate cancer (PCa). Here, we performed an integrative analysis of POSTN's role in patients with PCa. Clinical and POSTN data from large-scale datasets were analyzed. POSTN cutoffs were identified with X-Tile, and STRING was used for protein-protein interaction analysis. In a cohort of 48 patients with metastatic castration-resistant prostate cancer (mCRPC), we used the AdnaTest platform to isolate circulating tumor cells and extract POSTN mRNA. Plasma samples were also tested for POSTN protein expression by dot blot assay. Data from large-scale datasets did not reveal any association between POSTN genetic alterations and outcome. In primary tumors, we found a significant correlation between POSTN mRNA overexpression, worse baseline prognostic features, and shorter disease-free survival. POSTN was overexpressed in mCRPC and correlated with aggressive features. In our cohort of mCRPC patients, we found a positive correlation between POSTN plasma levels and androgen-receptor variant 7 positivity and an association with shorter overall survival. Our integrative analysis shows that POSTN is associated with poor clinical features and worse outcome in patients with PCa. Further studies are warranted to uncover the function of POSTN in PCa progression and to validate the prognostic significance of POSTN in mCRPC.

VDR in salivary gland homeostasis and cancer

The vitamin D receptor (VDR) and its ligand 1,25(OH)₂D₃ (1,25D) impact differentiation and exert anti-tumor effects in many tissues, but its role in salivary gland has yet to be defined. Using immunohistochemistry (IHC), we have detected strong VDR expression in murine and human salivary gland ducts. Compared to normal gland, VDR protein expression was retained in differentiated human pleomorphic adenoma (PA) but was undetectable in undifferentiated PA and in carcinomas, suggesting deregulation of VDR during salivary cancer progression. To gain insight into the potential role of VDR in salivary cancer, we assessed the effects of vitamin D in vivo and in vitro. Despite the presence of VDR in salivary gland, chronic dietary vitamin D restriction did not alter morphology of the salivary epithelium in C57/Bl6 mice. The localization of VDR in ductal epithelium prompted us to examine the effects of 1,25D in an established cell line (mSGc) derived from normal murine submandibular gland (SMG). This previously characterized cell line consists of multiple stem, progenitor and differentiated cell types as determined by mutually exclusive cellular expression of basal, ductal and myoepithelial markers. We demonstrated VDR expression and regulation of VDR target genes Vdr and Postn by 1,25D in mSGc, indicating functional ligand-mediated transcriptional activity. The effect of VDR signaling on epithelial differentiation markers was assessed by qPCR and IHC in mSGc cells treated with 1,25D. We found that 1,25D reduced mRNA expression of the basal cell progenitor marker keratin 5 (K5) and increased expression of the differentiated ductal cell marker keratin 7 (K7). Further, we found that 1,25D significantly decreased the number of proliferating cells, including proliferating K5⁺ cells. Characterization of cell cycle by Muse cytometry indicated 1,25D treatment decreased cells in S, G₂, and M phase. The inhibition of K5⁺ cell proliferation by 1,25D is of particular interest because K5⁺ basal cells contribute to a wide variety of salivary tumor types. Our studies suggest that 1,25D alters cancer-relevant progenitor and differentiation markers in the salivary gland.

Bone Marrow Mesenchymal Stromal Cell-Derived Periostin Promotes B-ALL Progression by Modulating CCL2 in Leukemia Cells

Periostin (POSTN) is a multifunctional extracellular component that regulates cell-matrix interactions and cell-cell crosstalk. POSTN deletion significantly decreases leukemia burden in mice; however, the underlying mechanisms by which POSTN promotes B cell acute lymphoblastic leukemia (B-ALL) progression remain largely unknown. Here, we demonstrate that bone marrow (BM)-derived mesenchymal stromal cells (BM-MSCs) express higher levels of POSTN when co-cultured with B-ALL cells in vitro and in vivo. POSTN deficiency in BM-MSCs significantly decreases CCL2 expression in co-cultured B-ALL cells in vitro and in vivo. Moreover, POSTN treatment increases expression of CCL2 in B-ALL cells by activating the integrin-ILK-NF-κB pathway. Conversely, CCL2 treatment upregulates expression of POSTN in BM-MSCs via STAT3 activation. Furthermore, there is a positive correlation between POSTN expression and CCL2 level in the BM of mice and patients with B-ALL. These findings suggest that B-ALL cell-derived CCL2 contributes to the increased leukemia burden promoted by BM-MSC-derived POSTN.

Revisiting Cancer Stem Cells as the Origin of Cancer-Associated Cells in the Tumor Microenvironment: A Hypothetical View from the Potential of iPSCs

The tumor microenvironment (TME) has an essential role in tumor initiation and development. Tumor cells are considered to actively create their microenvironment during tumorigenesis and tumor development. The TME contains multiple types of stromal cells, cancer-associated fibroblasts (CAFs), Tumor endothelial cells (TECs), tumor-associated adipocytes (TAAs), tumor-associated macrophages (TAMs) and others. These cells work together and with the extracellular matrix (ECM) and many other factors to coordinately contribute to tumor growth and maintenance. Although the types and functions of TME cells are well understood, the origin of these cells is still obscure. Many scientists have tried to demonstrate the origin of these cells. Some researchers postulated that TME cells originated from surrounding normal tissues, and others demonstrated that the origin is cancer cells. Recent evidence demonstrates that cancer stem cells (CSCs) have differentiation abilities to generate the original lineage cells for promoting tumor growth and metastasis. The differentiation of CSCs into tumor stromal cells provides a new dimension that explains tumor heterogeneity. Using induced pluripotent stem cells (iPSCs), our group postulates that CSCs could be one of the key sources of CAFs, TECs, TAAs, and TAMs as well as the descendants, which support the self-renewal potential of the cells and exhibit heterogeneity. In this review, we summarize TME components, their interactions within the TME and their insight into cancer therapy. Especially, we focus on the TME cells and their possible origin and also discuss the multi-lineage differentiation potentials of CSCs exploiting iPSCs to create a society of cells in cancer tissues including TME.

Fibronectin and Periostin as Prognostic Markers in Ovarian Cancer

Previously, based on a DNA microarray experiment, we identified a 96-gene prognostic signature associated with the shorter survival of ovarian cancer patients. We hypothesized that some differentially expressed protein-coding genes from this signature could potentially serve as prognostic markers. The present study was aimed to validate two proteins, namely fibronectin (FN1) and periostin (POSTN), in the independent set of ovarian cancer samples. Both proteins are mainly known as extracellular matrix proteins with many important functions in physiology. However, there are also indications that they are implicated in cancer, including ovarian cancer. The expression of these proteins was immunohistochemically analyzed in 108 surgical samples of advanced ovarian cancer (majority: high-grade serous) and additionally on tissue arrays representing different stages of the progression of ovarian and fallopian tube epithelial tumors, from normal epithelia, through benign tumors, to adenocarcinomas of different stages. The correlation with clinical, pathological, and molecular features was evaluated. Kaplan-Meier survival analysis and Cox-proportional hazards models were used to estimate the correlation of the expression levels these proteins with survival. We observed that the higher expression of fibronectin in the tumor stroma was highly associated with shorter overall survival (OS) (Kaplan-Meier analysis, log-rank test p = 0.003). Periostin was also associated with shorter OS (p = 0.04). When we analyzed the combined score, calculated by adding together individual scores for stromal fibronectin and periostin expression, Cox regression demonstrated that this joint FN1&POSTN score was an independent prognostic factor for OS (HR = 2.16; 95% CI: 1.02-4.60; p = 0.044). The expression of fibronectin and periostin was also associated with the source of ovarian tumor sample: metastases showed higher expression of these proteins than primary tumor samples (χ² test, p = 0.024 and p = 0.032). Elevated expression of fibronectin and periostin was also more common in fallopian cancers than in ovarian cancers. Our results support some previous observations that fibronectin and periostin have a prognostic significance in ovarian cancer. In addition, we propose the joint FN1&POSTN score as an independent prognostic factor for OS. Based on our results, it may also be speculated that these proteins are related to tumor progression and/or may indicate fallopian-epithelial origin of the tumor.

Overcoming the challenges of cancer drug resistance through bacterial-mediated therapy

Despite tremendous efforts to fight cancer, it remains a major public health problem and a leading cause of death worldwide. With increased knowledge of cancer pathways and improved technological platforms, precision therapeutics that specifically target aberrant cancer pathways have improved patient outcomes. Nevertheless, a primary cause of unsuccessful cancer therapy remains cancer drug resistance. In this review, we summarize the broad classes of resistance to cancer therapy, particularly pharmacokinetics, the tumor microenvironment, and drug resistance mechanisms. Furthermore, we describe how bacterial-mediated cancer therapy, a bygone mode of treatment, has been revitalized by synthetic biology and is uniquely suited to address the primary resistance mechanisms that confound traditional therapies. Through genetic engineering, we discuss how bacteria can be potent anticancer agents given their tumor targeting potential, anti-tumor activity, safety, and coordinated delivery of anti-cancer drugs.

Periostin: An emerging biomarker for allergic diseases

Periostin is a matricellular protein as well as an extracellular matrix (ECM) protein belonging to the fasciclin family. Periostin plays important roles as a matricellular protein in the setting of allergic diseases by binding to several integrins on various cells. Since periostin is induced mainly by IL-4 and IL-13, signature type 2 cytokines, and it is highly expressed in the subepithelial regions of many chronic allergic diseases, periostin has emerged as a novel biomarker reflecting type 2 inflammation in allergic diseases. It has, moreover, been revealed that periostin has characteristics different from other type 2 biomarkers such as eosinophil count and fractional exhaled nitric oxide (FeNO), reflecting fibrosis or tissue remodeling. From this, we may say that serum periostin is a "chronic" type 2 biomarker, whereas FeNO and possibly the eosinophil count are "acute" type 2 biomarkers. In contrast, it is still uncertain how we can apply periostin measurement to the use of biologics for allergic diseases. By examining the roles of periostin in allergy and the utility and potential of periostin in developing diagnostics against allergic diseases, it is hoped that in the near future, we can develop a new strategy to treat allergic patients.

Novel insights into the complex architecture of osteoporosis molecular genetics

Osteoporosis is a prevalent osteodegenerative disease and silent killer linked to a decrease in bone mass and decline of bone microarchitecture, due to impaired bone matrix mineralization, raising the risk of fracture. Nevertheless, the process of bone matrix mineralization is still an unsolved mystery. Osteoporosis is a polygenic disorder associated with genetic and environmental risk factors; however, the majority of genes associated with osteoporosis remain largely unknown. Several signaling pathways regulate bone mass; therefore, dysregulation of a single signaling pathway leads to metabolic bone disease owing to high or low bone mass. Parathyroid hormone, core-binding factor α-1 (Cbfa1), Wnt/β-catenin, the receptor activator of the nuclear factor kappa-B (NF-κB) ligand (RANKL), myostatin, and osteogenic exercise signaling pathways play pivotal roles in the regulation of bone mass. The myostatin signaling pathway increases bone resorption by activating the RANKL signaling pathway, whereas osteogenic exercise inhibits myostatin and sclerostin while inducing irisin that consequentially activates the Cbfa1 and Wnt/β-catenin bone formation pathways. The aims of this review are to summarize what is known about osteoporosis-related signaling pathways; define the role of these pathways in osteoporosis drug discovery; focus light on the link between bone, muscle, pancreas, and adipose integrative physiology and osteoporosis; and underline the emerging role of osteogenic exercise in the prevention of, and care for, osteoporosis, obesity, and diabetes.

Novel Targets for Therapy of Renal Fibrosis

Renal fibrosis is an important component of chronic kidney disease, an incurable pathology with increasing prevalence worldwide. With a lack of available therapeutic options, end-stage renal disease is currently treated with renal replacement therapy through dialysis or transplantation. In recent years, many efforts have been made to identify novel targets for therapy of renal diseases, with special focus on the characterization of unknown mediators and pathways participating in renal fibrosis development. Using experimental models of renal disease and patient biopsies, we identified four novel mediators of renal fibrosis with potential to constitute future therapeutic targets against kidney disease: discoidin domain receptor 1, periostin, connexin 43, and cannabinoid receptor 1. The four candidates were highly upregulated in different models of renal disease and were localized at the sites of injury. Subsequent studies showed that they are centrally involved in the underlying mechanisms of renal fibrosis progression. Interestingly, inhibition of either of these proteins by different strategies, including gene deletion, antisense administration, or specific blockers, delayed the progression of renal disease and preserved renal structure and function, even when the inhibition started after initiation of the disease. This review will summarize the current findings on these candidates emphasizing on their potential to constitute future targets of therapy.

Reversal of EGFR inhibitors' resistance by co-delivering EGFR and integrin αvβ3 inhibitors with nanoparticles in non-small cell lung cancer

Purpose: Tumor cells, with drug resistance, are associated with failed treatment and poor prognosis. Our aim was to explore potential strategy to overcome the epidermal growth factor receptor (EGFR) inhibitors resistance in non-small cell lung cancer (NSCLC).Materials and methods: Flow cytometry was used to examine and sort cells. Using MTT assay, we detected the cell viability under different conditions. Using RT-qPCR and Western blot, we determined the targeted gene expression in mRNA and protein levels. The morphology of the prepared nanoparticles was pictured by transmission electron microscopy. We also performed immunohistochemistry (IHC) and immunofluorescence (IF) to detect the proteins expression. Subcutaneous cancer models in nude mice were constructed to evaluate the anti-cancer effects in vivo Results: Here, we observed enhanced expression of integrin αvβ3 in tumor tissues from EGFR inhibitors resistant patients. Also, integrin αvβ3-positive NSCLC cells revealed significant EGFR inhibitors resistance, resulting from the activation of Galectin-3/KRAS/RalB/TBK1/NF-κB signaling pathway. Co-encapsulating integrin αvβ3 inhibitor and EGFR inhibitor further improved the drug delivery system, leading to superior anti-cancer effects and reduced systemic toxicity.Conclusion: Our results demonstrated that co-encapsulation of erlotinib and cilengitide by MPEG-PLA (Erlo+Cilen/PP) nanoparticles revealed enhanced tumor suppression along with reduced organ damages, providing an innovative approach for NSCLC treatment.

Attenuation of periostin in retinal Müller glia by TNF-α and IFN-γ

AIM

To investigate the regulation and mechanisms of periostin expression in retinal Müller glia, and to explore the relevance to retinal neovascularization.

METHODS

The oxygen-induced retinopathy (OIR) mouse model and the human Moorfield/Institute of Ophthalmology-Müller 1 (MIO-M1) cell line were used in the study. Immunofluorescence staining was used to determine the distribution and expression of periostin and a Müller glial cell marker glutamine synthetase (GS). Cytokines TNF-α and IFN-γ were added to stimulate the MIO-M1 cells. ShRNA was used to knockdown periostin expression in MIO-M1 cells. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) was conducted to assess the mRNA expression of periostin.

RESULTS

Immunofluorescence staining showed that periostin was expressed by MIO-M1 Müller glia. GS-positive Müller glia and periostin increased in OIR retinas, and were partially overlaid. The stimulation of TNF-α and IFN-γ reduced the mRNA expression of periostin significantly and dose-dependently in MIO-M1 cells. Knockdown of periostin reduced mRNA expression of vascular endothelial growth factor A (VEGFA) in MIO-M1 cells, while VEGFA expression was not changed in periostin knock-out OIR retinas.

CONCLUSION

Müller glia could be one of the main sources of periostin in the retina, and might contribute to the pathogenesis of retinal neovascularization. Proinflammatory cytokines TNF-α and IFN-γ attenuate the periostin expression in retinal Müller glia, which provides a potential and novel method in treating retinal neovascular diseases.

The C-Terminal Intact Forms of Periostin (iPTN) Are Surrogate Markers for Osteolytic Lesions in Experimental Breast Cancer Bone Metastasis

Periostin is an extracellular matrix protein that actively contributes to tumor progression and metastasis. Here, we hypothesized that it could be a marker of bone metastasis formation. To address this question, we used two polyclonal antibodies directed against the whole molecule or its C-terminal domain to explore the expression of intact and truncated forms of periostin in the serum and tissues (lung, heart, bone) of wild-type and periostin-deficient mice. In normal bones, periostin was expressed in the periosteum and specific periostin proteolytic fragments were found in bones, but not in soft tissues. In animals bearing osteolytic lesions caused by 4T1 cells, C-terminal intact periostin (iPTN) expression disappeared at the invasive front of skeletal tumors where bone-resorbing osteoclasts were present. In vitro, we found that periostin was a substrate for osteoclast-derived cathepsin K, generating proteolytic fragments that were not recognized by anti-periostin antibodies directed against iPTN. In vivo, using an in-house sandwich immunoassay aimed at detecting iPTN only, we observed a noticeable reduction of serum periostin levels (- 26%; P < 0.002) in animals bearing osteolytic lesions caused by 4T1 cells. On the contrary, this decrease was not observed in women with breast cancer and bone metastases when periostin was measured with a human assay detecting total periostin. Collectively, these data showed that mouse periostin was degraded at the bone metastatic sites, potentially by cathepsin K, and that the specific measurement of iPTN in serum should assist in detecting bone metastasis formation in breast cancer.

Periostin secreted by cancer-associated fibroblasts promotes cancer stemness in head and neck cancer by activating protein tyrosine kinase 7

Protein tyrosine kinase 7 (PTK7) and cancer-associated fibroblasts (CAFs) play important roles in cancer stemness, respectively. However, little is known about interaction between CAFs and PTK7 in cancers. In this study, we showed that PTK7 was significantly correlated with the Wnt/β-Catenin pathway and aggressive clinicopathologic features in human head and neck squamous cell carcinoma (HNSCC). Meanwhile, animal experiments showed that PTK7 enhanced chemoresistance and lung metastasis of HNSCC in vivo. In addition, co-immunoprecipitation (co-IP) assay demonstrated that POSTN secreted by CAFs was a potential upstream ligand of PTK7 which might act as a receptor. Further analysis revealed that POSTN promoted the cancer stem cell (CSC)-like phenotype via PTK7-Wnt/β-Catenin signaling, including the proliferation and invasion of HNSCC cells in vitro, as well as tumor initiation and progression in vivo. Collectively, our study proved that CAF-derived POSTN might promote cancer stemness via interacting with PTK7 in HNSCC, suggesting that the combination of POSTN and PTK7 might be a potential prognostic and diagnostic indicator and a  promising therapeutic target.