Matrix Gla protein repression by miR-155 promotes oncogenic signals in breast cancer MCF-7 cells

Thrombospondin 2, matrix Gla protein and digital analysis identified distinct fibroblast populations in fibrostenosing Crohn's disease

Fibrosis is an important complication in inflammatory bowel diseases. Previous studies suggest an important role of matrix Gla protein (MGP) and thrombospondin 2 (THBS2) in fibrosis in various organs. Our aim was to analyse their expression together with regulatory miRNAs in submucosal and subserosal fibroblasts in ulcerative colitis (UC) and Crohn's disease (CD) using immunohistochemistry and qPCR. Digital pathology was used to compare collagen fibre characteristics of submucosal and subserosal fibrosis. Immunohistochemistry showed expression of MGP, but not THBS2 in submucosa in UC and CD. In the subserosa, there was strong staining for both proteins in CD but not in UC. qPCR showed significant upregulation of THBS2 and MGP genes in CD subserosa compared to the submucosa. Digital pathology analysis revealed higher proportion of larger and thicker fibres that were more tortuous and reticulated in subserosal fibrosis compared to submucosal fibrosis. These results suggest distinct fibroblast populations in fibrostenosing CD, and are further supported by image analysis showing significant differences in the morphology and architecture of collagen fibres in submucosal fibrosis in comparison to subserosal fibrosis. Our study is the first to describe differences in submucosal and subserosal fibroblast populations, contributing to understanding of the pathogenesis of fibrostenosis in CD.

Assessment of MGP gene expression in cancer and contribution to prognosis

Matrix Gla protein (MGP) was first identified as a calcification physiological inhibitor and the causal agent of the Keutel syndrome. MGP has been suggested to play a role in development, cell differentiation, and tumorigenesis. This study aimed to compare MGP expression and methylation status in different tumors and adjacent tissues, using The Cancer Genome Atlas (TCGA) data repository. We investigated if changes in MGP mRNA expression were correlated to cancer progression and whether the correlation coefficients could be used for prognosis. Strong correlations were observed between altered MGP levels and disease progression in breast, kidney, liver, and thyroid cancers, suggesting that it could be used to complement current clinical biomarker assays, for early cancer diagnosis. We have also analyzed MGP methylation and identified CpG sites in its promoter and first intron with clear differences in methylation status between healthy and tumoral tissue providing evidence for epigenetic regulation of MGP transcription. Furthermore, we demonstrate that these alterations correlate with the overall survival of the patients suggesting that its assessment can serve as an independent prognostic indicator of patients' survival.

MicroRNA Dysregulation in Early Breast Cancer Diagnosis: A Systematic Review and Meta-Analysis

Breast cancer continues to be the leading cause of death in women worldwide. Mammography, which is the current gold standard technique used to diagnose it, presents strong limitations in early ages where breast cancer is much more aggressive and fatal. MiRNAs present in numerous body fluids might represent a new line of research in breast cancer biomarkers, especially oncomiRNAs, known to play an important role in the suppression and development of neoplasms. The aim of this systematic review and meta-analysis was to evaluate dysregulated miRNA biomarkers and their diagnostic accuracy in breast cancer. Two independent researchers reviewed the included studies according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. A protocol for this review was registered in PROSPERO with the registration number "CRD42021256338". Observational case-control-based studies analyzing concentrations of microRNAs which have been published within the last 10 years were selected, and the concentrations of miRNAs in women with breast cancer and healthy controls were analyzed. Random-effects meta-analyses of miR-155 were performed on the studies which provided enough data to calculate diagnostic odds ratios. We determined that 34 microRNAs were substantially dysregulated and could be considered biomarkers of breast cancer. Individually, miR-155 provided better diagnostic results than mammography on average. However, when several miRNAs are used to screen, forming a panel, sensitivity and specificity rates improve, and they can be associated with classic biomarkers such us CA-125 or CEA. Based on the results of our meta-analysis, miR-155 might be a promising diagnostic biomarker for this patient population.

New insights into vitamin K biology with relevance to cancer

Phylloquinone (vitamin K1) and menaquinones (vitamin K2 family) are essential for post-translational γ-carboxylation of a small number of proteins, including clotting factors. These modified proteins have now been implicated in diverse physiological and pathological processes including cancer. Vitamin K intake has been inversely associated with cancer incidence and mortality in observational studies. Newly discovered functions of vitamin K in cancer cells include activation of the steroid and xenobiotic receptor (SXR) and regulation of oxidative stress, apoptosis, and autophagy. We provide an update of vitamin K biology, non-canonical mechanisms of vitamin K actions, the potential functions of vitamin K-dependent proteins in cancer, and observational trials on vitamin K intake and cancer.

Expression level of miR-155, miR-15a and miR-19a in peripheral blood of ductal carcinoma breast cancer patients: Possible bioindicators for cellular inherent radiosensitivity

Examination of cellular radiosensitivity (RS) helps prevent the adverse side-effects of Radiotherapy in exposed patients. We aim to study whether miRNA-155 (miR-155), miR-19a and miR-15a can predict inherent RS according to cellular RS in breast cancer (BC) patients. This study was done on the blood samples of 40 invasive ductal carcinoma (IDC) BC patients and 15 healthy women. G2 assay was performed to evaluate cellular RS. To study the expression level of these miRNAs in blood, qRT-PCR was used. The sensitivity and specificity of the studied miRNAs were assessed by the receiver operating characteristic (ROC) curve. The yield of spontaneous (SY) and radiation-induced (RIY) chromatid breaks (CBs) was significantly different between control and patient groups (p < 0.0001). A cut-off value was specified to make distinct the patients with cellular RS to those without. Expression of miR-15a was significantly downregulated (p < 0.0001) in BC patients. However, miR-19a showed upregulation in the blood of BC patients. It was also found the expression level of miR-155 and miR-19a were significantly associated with frequency of CBs (FCB) (p < 0.05). ROC curve analysis manifested that the miR-15a and miR-19a differentiate BC patients and healthy women with 0.91 and 0.68 yielding an area under the ROC curve, respectively. miR-155 and miR-19a discriminate between BC patients with and without cellular RS with area under the ROC curve 0.98 and 0.68. Our findings uncovered miR-155 and miR-19a could be applied as a bioindicator to predict cellular radiosensitivity of BC patients.

GGCX variants leading to biallelic deficiency to γ-carboxylate GRP cause skin laxity in VKCFD1 patients

γ-Glutamyl carboxylase (GGCX) catalyzes the γ-carboxylation of 15 different vitamin K dependent (VKD) proteins. Pathogenic variants in GGCX cause a rare hereditary bleeding disorder called Vitamin K dependent coagulation factor deficiency type 1 (VKCFD1). In addition to bleedings, some VKCFD1 patients develop skin laxity and skeletal dysmorphologies. However, the pathophysiological mechanisms underlying these non-hemorrhagic phenotypes remain elusive. Therefore, we have analyzed 20 pathogenic GGCX variants on their ability to γ-carboxylate six non-hemostatic VKD proteins in an in vitro assay, where GGCX variants were expressed in GGCX^-/- cells and levels of γ-carboxylated co-expressed VKD proteins were detected by a functional ELISA. We observed that GGCX variants causing markedly reduced γ-carboxylation of Gla rich protein (GRP) in vitro were reported in patients with skin laxity. Reduced levels of γ-carboxylated Matrix gla protein (MGP) are not exclusive for causing skeletal dysmorphologies in VKCFD1 patients. In silico docking of vitamin K hydroquinone on a GGCX model revealed a binding site, which was validated by in vitro assays. GGCX variants affecting this site result in disability to γ-carboxylate VKD proteins and hence are involved in the most severe phenotypes. This genotype-phenotype analysis will help to understand the development of non-hemorrhagic phenotypes and hence improve treatment in VKCFD1 patients.

The Expression of miR-155-5p and Local Matrix Gla Protein in Meningiomas

Meningiomas are classified by the World Health Organization (WHO) in three grades, based on morphological features. Independent of this grading, the presence of calcification in meningiomas influences their growth rate. The messenger RNA of matrix Gla protein (MGP), an extra-hepatic protein with different conformations involved in the homeostasis of ectopic calcification has been found in meningiomas and was shown to be regulated in breast cancer by miR-155-5p, a specific micro RNA. Therefore, we investigated the expression of miR-155-5p and its relationship with local MGP conformations in different grade meningiomas. According to the WHO classification, our 41 samples of meningiomas were stratified in groups WHO I and WHO II. Using real time polymerase chain reaction, we observed a higher miR-155-5p expression in group WHO I versus group WHO II [with a fold change (FC) of 3.83, p=0.027)]. Moreover, the expression of miR-155-5p was higher in calcified tumors compared to non-calcified tumors in all samples (FC=3.01, p=0.047) and in group WHO I (FC=3.65, p=0.048). Utilizing immunohistochemistry, we determined the concurrent presence of all MGP conformations in calcified meningiomas. This study was the first to establish higher miR-155-5p expression in grade WHO I and calcified meningiomas, which could improve molecular classification and targeted therapy and also the presence of all MGP conformations in calcified meningiomas, confirming the existence of an anti-calcification mechanism in meningiomas..

Keutel Syndrome, a Review of 50 Years of Literature

Keutel syndrome (KS) is a rare autosomal recessive genetic disorder that was first identified in the beginning of the 1970s and nearly 30 years later attributed to loss-of-function mutations in the gene coding for the matrix Gla protein (MGP). Patients with KS are usually diagnosed during childhood (early onset of the disease), and the major traits include abnormal calcification of cartilaginous tissues resulting in or associated with malformations of skeletal tissues (e.g., midface hypoplasia and brachytelephalangism) and cardiovascular defects (e.g., congenital heart defect, peripheral pulmonary artery stenosis, and, in some cases, arterial calcification), and also hearing loss and mild developmental delay. While studies on Mgp -/- mouse, a faithful model of KS, show that pathologic mineral deposition (ectopic calcification) in cartilaginous and vascular tissues is the primary cause underlying many of these abnormalities, the mechanisms explaining how MGP prevents abnormal calcification remain poorly understood. This has negative implication for the development of a cure for KS. Indeed, at present, only symptomatic treatments are available to treat hypertension and respiratory complications occurring in the KS patients. In this review, we summarize the results published in the last 50 years on Keutel syndrome and present the current status of the knowledge on this rare pathology.

Indoxyl sulfate promotes osteogenic differentiation of vascular smooth muscle cells by miR-155-5p-dependent downregulation of matrix Gla protein via ROS/NF-κB signaling

Vascular calcification (VC) is a major risk factor for increasing cardiovascular morbidity and mortality in patients with chronic kidney disease (CKD). Indoxyl sulfate (IS), a representative uremic toxin, is closely associated with VC in CKD patients. Matrix Gla protein (MGP) plays pivotal role in VC as a calcification inhibitor. The aim of this work was to explore whether MGP was involved in IS-induced VC. Here, we demonstrated the role of MGP in the IS-induced osteogenic differentiation of human aortic smooth muscle cells (HASMCs). The methods included Von Kossa staining, immunohistochemistry, Alizarin Red staining, quantitative real-time PCR and western blotting. MGP was decreased in calcified arteries both in CKD patients and rats. In vitro, IS suppressed MGP expression in HASMCs by activating ROS/NF-κB signaling in parallel with osteogenic differentiation, which was mitigated by inhibiting ROS and NF-κB with diphenyleneiodonium and Bay11-7082. Further investigation showed that IS induced NF-κB-responsive microRNA (miR)-155-5p mediating MGP downregulation. Overexpression of miR-155-5p with mimics aggravated IS-induced MGP reduction and osteogenic differentiation. In contrast, these conditions were diminished by silencing miR-155-5p. We demonstrate that IS promotes the HASMCs phenotype switch by suppressing MGP expression via ROS/NF-κB/miR-155-5p signaling and provide a new insight for the pathogenesis of IS-induced VC.

Berberine Inhibits the Expression of SCT through miR-214-3p Stimulation in Breast Cancer Cells

In this study, we aimed to evaluate the suppressive abilities of berberine (BBR) on MCF-7 and MDA-MB-231 cells and confirm its underlying mechanisms on miR-214-3p. We first built a panel of 18 miRNAs and 9 lncRNAs that were reported to participate in the mechanism of breast cancer. The RT-qPCR results suggested that BBR illustrated a dosage-dependent pattern in the stimulation to miR-214-3p in both MCF-7 and MDA-MB-231 cells. Then, we performed gain-and-lose function tests to validate the role of miR-214-3p contributing to the anticancer effects of BBR. Both BBR and miR-214-3p mimic reduced the cell viability, repressed migration and invasion capacities, increased rates of total apoptotic cells and ratio of Bax/Bcl-2, and increased the percentage of G2/M cells of MCF-7 and MDA-MB-231 cells by colony formation and CKK8 assay, scratch wound healing and gelatin-based 3D conformation assay, transwell invasion assay, and cell cycle analysis, respectively. However, miR-214-3p inhibitor counteracted all these effects of BBR. Based on the bioinformatics analysis and dual-luciferase reporter test, we identified binding sites between SCT and miR-214-3p. We further confirmed that BBR massively and dose-dependently reduced the mRNA expression and protein levels of SCT in both MCF-7 and MDA-231 cells. We testified that both miR-214-3p mimic and BBR could decrease the mRNA expression and protein levels of SCT, while miR-214-3p inhibitor weakened these reductions. In conclusion, BBR suppressed MCF-7 and MDA-MB-231 breast cancer cells by upregulating miR-214-3p and increasing its inhibition to SCT.

Unique cartilage matrix-associated protein inhibits the migratory and invasive potential of triple-negative breast cancer

Triple-negative breast cancer (TNBC) that lacks expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) is a breast cancer subtype with very aggressive metastasis and poor prognosis. Unique cartilage matrix-associated protein (UCMA) is a vitamin K-dependent protein (VKDP) with a high-density γ-carboxyglutamic acid (Gla) domain due to the action of vitamin K. UCMA promotes osteoblast differentiation and mineral deposition in bone and suppresses calcification in vessels. However, correlation between UCMA and TNBC is unknown. This study investigated the inhibitory effect of UCMA on TNBC cell in vitro migration, invasion, and colony formation in addition to in vivo tumorigenesis. Cell migration and invasion significantly decreased in Ucma-overexpressing MDA-MB-231 and 4T1 cells compared to the mock control cells. Also, colony formation and the number of colonies significantly decreased in Ucma-overexpressing MDA-MB-231 and 4T1 cells. These results indicate that UCMA significantly inhibits the migration, invasion, and colony formation of TNBC cells. In an in vivo xenograft mouse model, tumor growth significantly decreased in mice bearing Ucma-overexpressing TNBC cells compared to the mock control cells, indicating that UCMA reduced in vivo tumor growth, similar to the inhibitory role of UCMA in vitro. Survival analysis using publicly available database showed that high UCMA expression significantly correlated with favorable relapse-free survival in TNBC patients compared to those with the other VKDPs, matrix Gla protein (MGP) and osteocalcin (OCN). Collectively, this study suggests that UCMA is a promising new therapeutic agent for TNBC.

Silencing of tumor-suppressive NR_023387 in renal cell carcinoma via promoter hypermethylation and HNF4A deficiency

Dysregulation of the epigenetic status of long noncoding RNAs (lncRNAs) has been linked to diverse human diseases including human cancers. However, the landscape of the whole-genome methylation profile of lncRNAs and the precise roles of these lncRNAs remain elusive in renal cell carcinoma (RCC). We first examined lncRNA expression profiles in RCC tissues and corresponding adjacent normal tissues (NTs) to identify the lncRNA signature of RCC, then lncRNA Promoter Microarray was performed to depict the whole-genome methylation profile of lncRNAs in RCC. Combined analysis of the lncRNAs expression profiles and lncRNAs Promoter Microarray identified a series of downregulated lncRNAs with hypermethylated promoter regions, including NR_023387. Quantitative real-time polymerase chain reaction (RT-PCR) implied that NR_023387 was significantly downregulated in RCC tissues and cell lines, and lower expression of NR_023387 was correlated with shorter overall survival. Methylation-specific PCR, MassARRAY, and demethylation drug treatment indicated that hypermethylation in the NR_023387 promoter contributed to its silencing in RCC. Besides, HNF4A regulated the expression of NR_023387 via transcriptional activation. Functional experiments demonstrated NR_023387 exerted tumor-suppressive roles in RCC via suppressing the proliferation, migration, invasion, tumor growth, and metastasis of RCC. Furthermore, we identified MGP as a putative downstream molecule of NR_023387, which promoted the epithelial-mesenchymal transition of RCC cells. Our study provides the first whole-genome lncRNA methylation profile in RCC. Our combined analysis identifies a tumor-suppressive and prognosis-related lncRNA NR_023387, which is silenced in RCC via promoter hypermethylation and HNF4A deficiency, and may exert its tumor-suppressive roles by downregulating the oncogenic MGP.

Evaluation of MGP gene expression in colorectal cancer

PURPOSE

Matrix Gla protein (MGP) is a vitamin K-dependent, γ-carboxylated protein that was initially found to be a physiological inhibitor of ectopic calcifications affecting mainly cartilage and the vascular system. Mutations in the MGP gene were found to be responsible for a human pathology, the Keutel syndrome, characterized by abnormal calcifications in cartilage, lungs, brain and vascular system. MGP was recently implicated in tumorigenic processes such as angiogenesis and shown to be abnormally regulated in several tumors, including cervical, ovarian, urogenital and breast. This fact has triggered our interest in analyzing the expression of MGP and of its regulator, the transcription factor runt related transcription factor 2 (RUNX2), in colorectal cancer (CRC).

METHODS

MGP and RUNX2 expression were analyzed in cancer and non-tumor biopsies samples from 33 CRC patients and 9 healthy controls by RT-qPCR. Consequently, statistical analyses were performed to evaluate the clinical-pathological significance of MGP and RUNX2 in CRC. MGP protein was also detected by immunohistochemical analysis.

RESULTS

Showed an overall overexpression of MGP in the tumor mucosa of patients at mRNA level when compared to adjacent normal mucosa and healthy control tissues. In addition, analysis of the expression of RUNX2 mRNA demonstrated an overexpression in CRC tissue samples and a positive correlation with MGP expression (Pearson correlation coefficient 0.636; p ≤ 0.01) in tumor mucosa. However correlations between MGP gene expression and clinical-pathological characteristics, such as gender, age and pathology classification did not provide relevant information that may shed light towards the differences of MGP expression observed between normal and malignant tissue.

CONCLUSIONS

We were able to associate the high levels of MGP mRNA expression with a worse prognosis and survival rate lower than five years. These results contributed to improve our understanding of the molecular mechanism underlying MGP deregulation in cancer.

BONE MARKERS IN ARTHROPATHIES

Bone endures a lifelong course of construction and destruction, with bone marker (BM) molecules released during this cycle. The field of measuring BM levels in synovial fluid and peripheral blood is a cardinal part of bone research within modern clinical medicine and has developed extensively in the last years. The purpose of our work was to convey an up-to-date overview on synovial fluid and serum BMs in the most common arthropathies.

Upregulation of MGP by HOXC8 promotes the proliferation, migration, and EMT processes of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype which accounts for 15%-20% of all breast cancer cases. The management of TNBC has remained a challenge due to its lack of targeted therapy. Previously, we reported that homeobox C8 (HOXC8) was involved in metastasis and migration of breast cancer cells. By chromatin immunoprecipitation and luciferase assays, we found that HOXC8 functioned as a transcription factor to activate the transcription of matrix Gla protein (MGP) gene, leading to an increase in the proliferation, anchorage-independent growth, and migration of TNBC cells. We further demonstrated that MGP expression promoted the epithelial-mesenchymal transition (EMT) process of TNBC cells, but not the other subtypes of breast cancer, suggesting that MGP induced EMT to promote proliferation and migration of TNBC cells. Moreover, we found that MGP was upregulated in clinical breast specimens compared to normal breast tissues and high MGP expression was statistically associated with poor, relapse-free survival for TNBC patients, indicating that MGP is probably a novel biomarker or therapeutic target for TNBC patients. Together, our results showed that the HOXC8-MGP axis played an important role in the tumorigenesis of TNBC and might be a promising therapeutic target for TNBC treatment.

Downregulation of matrix Gla protein is a biomarker for tamoxifen-resistant and radioresistant breast cancer

Aim: To establish downregulated biomarkers for cross-resistance for radiotherapy (RT) in tamoxifen (TAM)-resistant breast cancer cells. Materials & methods: RNA sequencing was performed on TAM and RT-resistant breast cancer cells. Breast cancer patient cohorts were queried in silico for associations between genes of interest and outcome after TAM treatment or irradiation. Results: 20 genes showed decreased expression in both TAM-resistant and RT-resistant breast cancer cells. Only matrix Gla protein in the primary tumor was associated with outcome after TAM treatment or RT in breast cancer patients. Conclusion: Matrix Gla protein is a biomarker for therapy sensitivity in breast cancer.

Single-cell RNA sequencing reveals novel gene expression signatures of trastuzumab treatment in HER2+ breast cancer: A pilot study

Human epidermal growth factor receptor 2-positive (HER2+) breast cancer accounts for ∼20% of invasive breast cancers and is associated with poor prognostics. The recent outcome of HER2+ breast cancer treatment has been vastly improved owing to the application of antibody-targeted therapies. Trastuzumab (Herceptin) is a monoclonal antibody designed to target HER2+ breast cancer cells. In addition to improved survival in the adjuvant treatment of HER2+ breast cancer, trastuzumab treatment has also been associated with cardiotoxicity side effect. However, the molecular mechanisms of trastuzumab action and trastuzumab-mediated cardiotoxicity are still not fully understood. Previous research utilized bulk transcriptomics analysis to study the underlining mechanisms, which relied on averaging molecular signals from bulk tumor samples and might have overlooked key expression features within breast cancer tumor. In contrast to previous research, we compared the single cancer cell level transcriptome profile between trastuzumab-treated and nontreated patients to reveal a more in-depth transcriptome profile. A total of 461 significantly differential expressed genes were identified, including previously defined and novel gene expression signatures. In addition, we found that trastuzumab-enhanced MGP gene expression could be used as prognostics marker for longer patient survival in breast invasive carcinoma patients, and validated our finding using TCGA (The Cancer Genome Atlas) breast cancer dataset. Moreover, our study revealed a 48-gene expression signature that is associated with cell death of cardiomyocytes, which could be used as early biomarkers for trastuzumab-mediated cardiotoxicity. This work is the first study to look at single cell level transcriptome profile of trastuzumab-treated patients, providing a new understanding of the molecular mechanism(s) of trastuzumab action and trastuzumab-induced cardiotoxicity side effects.

miR-155 in cancer drug resistance and as target for miRNA-based therapeutics

Small non-coding microRNAs (miRNAs) are instrumental in physiological processes, such as proliferation, cell cycle, apoptosis, and differentiation, processes which are often disrupted in diseases like cancer. miR-155 is one of the best conserved and multifunctional miRNAs, which is mainly characterized by overexpression in multiple diseases including malignant tumors. Altered expression of miR-155 is found to be associated with various physiological and pathological processes, including hematopoietic lineage differentiation, immune response, inflammation, and tumorigenesis. Furthermore, miR-155 drives therapy resistance mechanisms in various tumor types. Therefore, miR-155-mediated signaling pathways became a potential target for the molecular treatment of cancer. In this review, we summarize the current findings of miR-155 in hematopoietic lineage differentiation, the immune response, inflammation, and cancer therapy resistance. Furthermore, we discuss the potential of miR-155-based therapeutic approaches for the treatment of cancer.

Functional Role of Matrix gla Protein in Glioma Cell Migration

Glioblastoma multiforme (GBM) is the most common and aggressive brain tumor subtype. Despite that metastasis of GBM beyond the central nervous system (CNS) is rare, its malignancy is attributed to the highly infiltration trait, leading to the difficulty of complete surgical excision. Matrix gla protein (MGP) is a vitamin K-dependent small secretory protein, and functions as a calcification inhibitor. The involvement of MGP function in glioma cell dynamics remains to be clarified. The study showed that a low proliferative rat C6 glioma cell line named as C6-2 exhibited faster migratory and invasive capability compared to that observed in a high tumorigenic rat C6 glioma cell line (called as C6-1). Interestingly, C6-2 cells expressed higher levels of MGP molecules than C6-1 cells did. Lentivirus-mediated short hairpin RNA (shRNA) against MGP gene expression (MGP-KD) in C6-2 cells or lentivirus-mediated overexpression of MGP transcripts in C6-1 cells resulted in the morphological alteration of the two cell lines. Moreover, MGP-KD caused a decline in cell migration and invasion ability of C6-2 cells. In contrast, increased expression of MGP in C6-1 cells promoted their cell migration and invasion. The observations were further verified by the results from the implantation of C6-1 and C6-2 cells into ex vivo brain slice and in vivo rat brain. Thus, our results demonstrate that the manipulation of MGP expression in C6 glioma cells can mediate glioma cell migratory activity. Moreover, our findings indicate the possibility that high proliferative glioma cells expressing a high level of MGP may exist and contribute to tumor infiltration and recurrence.

Implication of a novel vitamin K dependent protein, GRP/Ucma in the pathophysiological conditions associated with vascular and soft tissue calcification, osteoarthritis, inflammation, and carcinoma

Gla-rich protein (GRP) or unique cartilage matrix-associated protein (Ucma), the newest member of vitamin K dependent proteins, carries exceptionally high number of γ-carboxyglutamic acid (Gla) residues which contributes to its outstanding capacity of binding with calcium in the extracellular environment indicating its potential role as a global calcium modulator. Recent studies demonstrated a critical function of GRP in the regulation of different pathophysiological conditions associated with vascular and soft tissue calcification including cardiovascular diseases, osteoarthritis, inflammation, and skin and breast carcinomas. These findings established an important relationship between γ-carboxylation of GRP and calcification associated disease pathology suggesting a critical role of vitamin K in the pathophysiological features of various health disorders. This review for the first time summarizes all of the updated findings related to the functional activities of GRP in the pathogenesis of several diseases associated with vascular and soft tissue mineralization, osteoarthritis, inflammation, and carcinoma. The outcome of this review will improve the understanding about the role of GRP in the pathogenesis of tissue calcification and its associated health disorders, which should in turn lead to the design of clinical interventions to improve the condition of patients associated with these health disorders.

Exosome-mediated breast cancer chemoresistance via miR-155 transfer

Breast cancer remains the most prevalent cause of cancer mortality in woman worldwide due to the metastatic process and therapy resistance. Resistance against cancer therapy is partially attributed to cancer stem cells (CSCs). These cells arise from epithelial cells undergoing epithelial-to-mesenchymal transition (EMT) and might be responsible for tumor recurrence. In this study, we reported the relevance of miR-155 upregulation in chemoresistant cells associated with EMT. Notably, we found miR-155 induction in exosomes isolated from CSCs and resistant cells, followed by resistant cells’ exosome transfer to the recipient sensitive cells. Functionally, miR-155 mimic assay showed an enrichment in miR-155 from exosome concomitant with miR-155 exosome transfer to breast cancer cells. In parallel to these effects, we also observed EMT change in miR-155 transfected cells. The chemoresistance phenotype transfer to sensitive cells and the migration capability was analyzed by MTT and scratch assays and our results suggest that exosomes may intermediate resistance and migration capacity to sensitive cells partly through exosome transfer of miR-155. Taken together, our findings establish the significance of exosome-mediate miR-155 chemoresistance in breast cancer cells, with implications for targeting miR-155 signaling as a possible therapeutic strategy.

MiR-155 Promotes Uveal Melanoma Cell Proliferation and Invasion by Regulating NDFIP1 Expression

MicroRNAs refer to small RNA molecules that destroy the messenger RNA by binding on them inhibiting the production of protein. However, the role of miR-155 in uveal melanoma metastasis remains largely unknown. In this study, we found that miR-155 was upregulated in both uveal melanoma cells and tissues. Transfection of miR-155 mimic into uveal melanoma cells led to an increase in cell growth and invasion; in contrast, inhibition of miR-155 resulted in opposite effects. Also, we identified Nedd4-family interacting protein 1 as a direct target of miR-155, and the expression of Nedd4-family interacting protein 1 was inhibited by miR-155. Furthermore, ectopic expression of Nedd4-family interacting protein 1 restored the effects of miR-155 on cell proliferation and invasion of uveal melanoma cells. In conclusion, miR-155 acts as a tumor promotor in uveal melanoma through increasing cell proliferation and invasion. Thus, miR-155 might serve as a potential therapeutic target in patients with uveal melanoma.

Vitamin K and cancer

Subclinical vitamin K deficits refer to carboxylation defects of different types of vitamin K-dependent hepatic and extrahepatic so-called Gla proteins without prolongation of the prothrombin time. This condition has been reported in different clinical situations due to insufficient supply or malabsorption of vitamin K as well as drug interactions. This review discusses the effects of different vitamin K subspecies on tumour growth and the possible anti-tumour effects of increased vitamin K intake. Blocking carboxylation of vitamin K-dependent proteins with warfarin anticoagulation - what are the risks/benefits for carcinogenesis? Previous studies on both heparin and low molecular weight heparin blocking of the vitamin K-dependent factors X and II have shown tumour suppressive effects. Vitamin K has anti-inflammatory effects that could also impact carcinogenesis, but little data exists on this subject.

MicroRNA-155 regulates the proliferation, cell cycle, apoptosis and migration of colon cancer cells and targets CBL

MicroRNA-155 (miR-155) is a well-studied miR and acts as an oncomiR in numerous cancer types. However, the biological functions of miR-155 in colon cancer as well as its target genes have remained to be fully elucidated. In order to investigate the biological functions of miR-155, MTT, colony formation and wound healing assays, cell cycle analysis and detection of apoptosis were performed. The results demonstrated that miR-155 promoted the proliferation of colon cancer cells and enhanced their colony formation capacity, promoted their cell cycle progression and inhibited apoptosis. miR-155 also promoted the migration of colon cancer cells. In the present study, casitas B-lineage lymphoma was identified as a novel target of miR-155. The present study suggested that miR-155 functions as an oncomiR in colon cancer cells and may become a promising therapeutic target for colon cancer therapy.

A single gene connects stiffness in glaucoma and the vascular system

Arterial calcification results in arterial stiffness and higher systolic blood pressure. Arterial calcification is prevented by the high expression of the Matrix-Gla gene (MGP) in the vascular smooth muscle cells (VSMC) of the arteries' tunica media. Originally, MGP, a gene highly expressed in cartilage and VSMC, was found to be one of the top expressed genes in the trabecular meshwork. The creation of an Mgp-lacZ Knock-In mouse and the use of mouse genetics revealed that in the eye, Mgp's abundant expression is localized and restricted to glaucoma-associated tissues from the anterior and posterior segments. In particular, it is specifically expressed in the regions of the trabecular meshwork and of the peripapillary sclera that surrounds the optic nerve. Because stiffness in these tissues would significantly alter outflow facility and biomechanical scleral stress in the optic nerve head (ONH), we propose MGP as a strong candidate for the regulation of stiffness in glaucoma. MGP further illustrates the presence of a common function affecting key glaucomatous parameters in the front and back of the eye, and thus offers the possibility for a sole therapeutic target for the disease.