Decorin mRNA Research Articles

Effects of mechanical stretching on the morphology of extracellular polymers and the mRNA expression of collagens and small leucine-rich repeat proteoglycans in vaginal fibroblasts from women with pelvic organ prolapse.

To determine the effect of mechanical stretching load and the efficacy of postmenopausal estrogen therapy (ET) on pelvic organ prolapse (POP), vaginal fibroblasts isolated from postmenopausal women with or without POP were subjected to 0.1-Hz uniaxial cyclic mechanical stretching (CS) with 10% elongation and 10−8 M 17-β-estradiol (E2) treatment. We investigated the morphological characteristics of extracellular polymers using scanning electron microscopy (SEM) and monitored the mRNA expression of type I collagen (COL I) and type III collagen (COL III) as well as the small leucine-rich proteoglycan (SLRP) family members decorin (DCN), biglycan (BGN), fibromodulin (FMO), and lumican (LUM), using real-time quantitative polymerase chain reaction (RT-PCR). Using SEM, certain viscoelastic polymers were found to be randomly distributed among fibroblasts, which for normal fibroblasts formed clusters of plum flower-like patterns under static-culture conditions and resembled stretched strips when stretched in culture, whereas polymers among POP fibroblasts resembled stretched strips under static-cultured conditions and presented broken networks when stretched in culture. RT-PCR revealed that COL I, DCN, BGN, FMO, and LUM mRNA expression was significantly higher in POP than in normal fibroblasts under static-culture condition. Following CS, COL I and BGN mRNA expression was significantly up-regulated in normal fibroblasts, and DCN and FMO mRNA expression was down-regulated in POP fibroblasts. Following concomitant CS and E2 treatment, significantly elevated COL I and DCN mRNA expression was observed in normal fibroblasts, and significantly elevated COL I and BGN mRNA expression was observed in POP fibroblasts. COL III mRNA expression was not significantly different between the POP and normal group, and CS did not significantly affect expression in either group, though COL III was down-regulated in normal fibroblasts concomitantly treated with E2 and CS. We conclude that the morphological distribution of extracellular polymers in POP fibroblasts exhibited higher sensitivity and lower tolerance to stretching loads than do normal fibroblasts. These mechanical properties were further reflected in the transcription of COL I. Defects in the compensatory function of BGN for DCN and LUM for FMO exist in POP fibroblasts, which further affect the structure and function of COL I in response to stretching load, ultimately resulting in abnormal reconstruction of pelvic supportive connective tissues and the occurrence of POP. ET can maintain stretching-induced elevations in COL I and DCN transcription in healthy women and improve stretching-induced COL I, DCN, BGN, and FMO transcriptional changes in POP women to prevent and improve POP. Only down-regulated COL III transcription was observed upon concomitant CS and E2 treatment in normal fibroblasts, which suggests that the tensile strength, not the elasticity, of the supportive connective tissues is damaged in POP and that the higher tensile strength induced by ET in healthy fibroblasts prevents POP. These findings confirm the role of higher sensitivity and lower tolerance to mechanical stretching in the pathogenesis of POP and further provide evidence supporting the use of ET to prevent and inhibit POP in postmenopausal women.

Biglycan and Decorin Expression and Distribution in Palatal Adhesion

Previous studies demonstrated that chondroitin sulfate proteoglycans (CSPGs) on apical surfaces of palatal medial edge epithelial (MEE) cells were necessary for palatal adhesion. In this study, we identified 2 proteoglycans, biglycan and decorin, that were expressed in the palatal shelves prior to adhesion. In addition, we established that these proteoglycans were dependent on transforming growth factor β (TGFβ) signaling. Laser capture microdissection was used to collect selected palatal epithelial cells from embryonic mouse embryos at various palate development stages. The expression of specific messenger RNA (mRNA) for biglycan and decorin was determined with quantitative real-time polymerase chain reaction. The TGFβrI kinase inhibitor (SB431542) was used in palatal organ cultures to determine if blocking TFGβ signaling changed biglycan and decorin distribution. Immunohistochemistry of both biglycan and decorin revealed expression on the apical and lateral surfaces of MEE cells. Biglycan protein and mRNA levels peaked as the palatal shelves adhered. Decorin was less abundant on the apical epithelial surface and also had reduced mRNA levels compared to biglycan. Their proteins were not expressed on MEE cells of palates treated with SB431542, an inhibitor of TGFβ signaling. The temporal expression of biglycan and decorin on the apical surface of MEE, combined with the evidence that these proteins were regulated through the TGFβ pathway, indicated that they may be important for adhesion.

Decorin expression is decreased in first trimester placental tissue from pregnancies with small for gestation age infants at birth

Fetal growth restriction (FGR) is a leading cause of perinatal morbidity and mortality. FGR pregnancies are often associated with histological evidence of placental vascular thrombosis. The proteoglycans are important components and regulators of vascular homeostasis. Previous studies from our laboratory highlighted mRNA and protein expression differences in placental proteoglycan decorin (DCN), within a clinically well-characterised cohort of third-trimester idiopathic FGR compared with gestation-matched uncomplicated control pregnancies. We also showed that decorin contributes to abnormal angiogenesis and increased thrombin generation in vitro. These observations suggest that DCN gene expression may contribute to the etiology of FGR. Small for gestational age (SGA) is frequently used as a proxy for FGR and is defined as a birth weight below the 10th percentile of a birth weight curve. We therefore made use of a unique resource of first trimester tissues obtained via chorionic villus sampling during the first trimester to investigate the temporal relationship between altered DCN expression and any subsequent development of SGA. We hypothesized that placental DCN expression is decreased early in gestation in SGA pregnancies. Surplus chorionic villus specimens from 15 women subsequently diagnosed with FGR and 50 from women with uncomplicated pregnancies were collected. DCN mRNA and DCN protein were determined using real-time PCR and immunoblotting, respectively. Both DCN mRNA and protein were significantly decreased in placentae from first-trimester SGA-pregnancies compared with controls (p < 0.05). This is the first study to report a temporal relationship between altered placental DCN expression and subsequent development of SGA.

Influences of human dermis derived mesenchymal stem cells on α-SMA and DCN expressions of hypertrophic scars fibroblasts

To preliminarily explore the effects of human dermis derived mesenchymal stem cells (hDMSCs) on expressions of α-smooth muscle actin (α-SMA) and decorin (DCN) in hypertrophic scars fibroblasts (HSFB) at different periods,and to explore the feasibility of MSCs in prevention and treatment of HSFBs. hDMSCs were cultured with mechanical method combined with enzyme digestion.The cells of the third generation which were well grown were taken,and flow cytometry (FCM) was used to detect CD molecules in hDMSCs.Immunocytochemistry was used to detect cytokeratin 19 (CK19) and vimentin and identify the separated cells.The cells were differentiated into lipoblasts,chondroblasts and osteoblasts.According to the formation course of hypertrophic scar,the scar specimens were divided into 6-month,l-year,and 2-year group with three cases in each group.HSFBs from different groups were co-cultured with well-adherent hDMSCs of the third generation in non-contact transwell co-culture system for 21 days. And HSFBs from the corresponding groups were cultured in normal six-well plate as the controls.Real-time fluorescent-polymerase chain reaction (RT-PCR) and Western Blot were used to detect the expressions of mRNA and proteins of α-SMA and DCN in HSFBs from different groups. hDMSCs highly expressed the surface markers including CD73,CD105,CD44 and CD90,etc.,but did not express hematopoietic stem cell surface markers including CD 14,CD34 and CD45.They positively expressed vimentin but not CK19.The cells can be differentiated into lipoblasts,chondroblasts and osteoblasts,which was in line with the minimum identification standards of mesenchymal stem cells.For HSFB cultured in normal six-well plates,α-SMA mRNA and protein expressions of HSFB in the 6-month,1-year and 2-year groups were 198.20 ± 15.46/0.29 ± 0.070,175.24 ± 17.04/0.38 ± 0.110,and 125.73 ± 6.99/0.33 ±0.085,respectively;while DCN mRNA and protein expressions of HSFB in the corresponding groups were 61.30 ± 9.79/0.015 ± 0.003,70.89 ± 11.29/0.020 ± 0.007,and 77.31 ± 4.80/0.023 ± 0.003,respectively.For HSFB co-cultured with 5 × 104 hDMSCs, oα-SMA mRNA and protein expressions of HSFB in the 6-month,1-year and 2-year groups were 48.40 ± 6.42/ 0.100 ± 0.020,192.16 ± 11.37/0.110 ± 0.014,and 73.33 ± 6.29/0.110 ± 0.016,respectively;while DCN mRNA and protein expressions of HSFB in the corresponding groups were 156.92 ± 14.91/0.049 ±0.015,154.42 ± 18.17/0.033 ± 0.008,and 140.82 ± 7.32/0.030 ± 0.004,respectively.Compared with the control group(Cultured in normal six-well plates), mRNA and protein expressions of α-SMA in HSFBs were decreased after co-culture with 5 × 104 hDMSCs, mRNA and protein expressions of DCN were increased. Furthermore, it suggested that hypertrophic scar changed significantly in the early formation stage namely in the 6-month group. hDMSCs can down-regulate α-SMA mRNA and protein expressions of HSFBs and up-regulate mRNA and protein expressions of DCN in the in-vitro culture system.Those effects were particularly obvious on fibroblasts at the early formation of hyperplastic scar.Anti fibrosis role of hDMSCs is expected to be used in increasing the healing quality of the wound and in the prevention and treatment of pathological scars.

Molecular cloning, expression analysis, and function of decorin in goat ovarian granulosa cells

Decorin (DCN), a component of the extracellular matrix (ECM), participates in ECM assembly and influences cell proliferation and apoptosis in many mammalian tissues and cells. However, expression and function of DCN in the ovary remain unclear. This study cloned the full-length cDNA of goat DCN obtained from the ovary of an adult goat. Sequence analysis revealed that the putative DCN protein shared a highly conserved amino acid sequence with known mammalian homologs. The tissue distribution of DCN mRNA expression was evaluated by real-time PCR, and the results showed that DCN was widely expressed in the tissues of adult goat. Immunohistochemistry results suggested that DCN protein existed in the granulosa cells and oocytes from all types of follicles and theca cells of antral follicles. Moreover, hCG-induced DCN mRNA expression was significantly reduced by the inhibitors of protein kinase A, PI3K, or p38 kinase (P < 0.05), which are key mediators involved in hCG-induced DCN expression. Overexpression of DCN significantly increased apoptosis and blocked cell cycle progression in cultured granulosa cells (P < 0.05). Western blot analysis also showed that overexpression of DCN upregulated the expression levels of p21 protein (P < 0.05), whereas no effects were observed on the expression of Bax and Bcl-2 and on Bcl-2/Bax ratio (P > 0.05). These findings suggested that DCN regulates the apoptosis and cell cycle of granulosa cells.

Proteoglycans in Leiomyoma and Normal Myometrium: Abundance, Steroid Hormone Control, and Implications for Pathophysiology.

Uterine leiomyoma are a common benign pelvic tumors composed of modified smooth muscle cells and a large amount of extracellular matrix (ECM). The proteoglycan composition of the leiomyoma ECM is thought to affect pathophysiology of the disease. To test this hypothesis, we examined the abundance (by immunoblotting) and expression (by quantitative real-time polymerase chain reaction) of the proteoglycans biglycan, decorin, and versican in leiomyoma and normal myometrium and determined whether expression is affected by steroid hormones and menstrual phase. Leiomyoma and normal myometrium were collected from women (n = 17) undergoing hysterectomy or myomectomy. In vitro studies were performed on immortalized leiomyoma (UtLM) and normal myometrial (hTERT-HM) cells with and without exposure to estradiol and progesterone. In leiomyoma tissue, abundance of decorin messenger RNA (mRNA) and protein were 2.6-fold and 1.4-fold lower, respectively, compared with normal myometrium. Abundance of versican mRNA was not different between matched samples, whereas versican protein was increased 1.8-fold in leiomyoma compared with myometrium. Decorin mRNA was 2.4-fold lower in secretory phase leiomyoma compared with proliferative phase tissue. In UtLM cells, progesterone decreased the abundance of decorin mRNA by 1.3-fold. Lower decorin expression in leiomyoma compared with myometrium may contribute to disease growth and progression. As decorin inhibits the activity of specific growth factors, its reduced level in the leiomyoma cell microenvironment may promote cell proliferation and ECM deposition. Our data suggest that decorin expression in leiomyoma is inhibited by progesterone, which may be a mechanism by which the ovarian steroids affect leiomyoma growth and disease progression.

Restraint of Trophoblast Invasion of the Uterus by Decorin: Role in Pre-eclampsia.

Decorin (DCN) is a leucine-rich, TGF-β binding proteoglycan produced by mesenchymal cells including chondrocytes, dermal fibroblasts, and uterine decidual cells. It exerts multiple physiological functions including collagen fibrillogenesis, myogenesis, angiostasis, and restraining placental invasiveness. We discovered that decidua-derived DCN restrains proliferation, migration, and invasion of extravillous trophoblast (EVT) cells of the human placenta in a TGF-β-independent manner. These functions were differentially mediated by binding of DCN to multiple tyrosine kinase receptors (TKR) including EGFR, IGFR1, and VEGFR2. DCN blocked VEGFR-2 dependent EVT cell migration and endovascular differentiation by inhibiting P38MAPK and ERK1/2 pathways.We identified the avid VEGFR2 binding site in DCN protein as a 12 amino acids (LGTNPLKSSGIE) span in the Leucine-rich-repeat (LRR) 5 region of domain III. A single amino acid mutation (substitution of K to A) of DCN at this site abrogated VEGFR-2- dependent DCN actions. Also, DCN mRNA expression, measured with in situ hybridization, was selectively upregulated in decidual cells in placentas from mothers suffering from pre-eclampsia (PE), whereas the expression levels remained unchanged in chorionic villus mesenchymal cells. This difference between PE and control placentas was present at all gestational ages, indicating the pathogenic role of DCN in PE. We hypothesize that increased blood DCN levels could be a candidate biomarker for PE.

Decorin in Human Colon Cancer

Decorin is generally recognized as a tumor suppressing molecule. Nevertheless, although decorin has been shown to be differentially expressed in malignant tissues, it has often remained unclear whether, in addition to non-malignant stromal cells, cancer cells also express it. Here, we first used two publicly available databases to analyze the current information about decorin expression and immunoreactivity in normal and malignant human colorectal tissue samples. The analyses demonstrated that decorin expression and immunoreactivity may vary in cancer cells of human colorectal tissues. Therefore, we next examined decorin expression in normal, premalignant and malignant human colorectal tissues in more detail using both in situ hybridization and immunohistochemistry for decorin. Our results invariably demonstrate that malignant cells within human colorectal cancer tissues are devoid of both decorin mRNA and immunoreactivity. Identical results were obtained for cells of neuroendocrine tumors of human colon. Using RT-qPCR, we showed that human colon cancer cell lines are also decorin negative, in accordance with the above in vivo results. Finally, we demonstrate that decorin transduction of human colon cancer cell lines causes a significant reduction in their colony forming capability. Thus, strategies to develop decorin-based adjuvant therapies for human colorectal malignancies are highly rational.

Effect of decorin gene overexpression on cell cycle and apoptosis of QBC939 cells

Objective To investigate the effects of decorin(DCN)gene overexpression on cell cycle and apoptosis of human cholangiocarcinoma cells. Methods The pEGFP-DCN plasmids and pEGFP-N1 control plasmids were transfected into the QBC939 cells using Lipofectamine 2000. The mRNA and protein expression of decorin in QBC939 cells transfected with plasmid overexpressing decorin was detected by real-time reverse transcriptase-polymerase chain reaction(RT-qPCR) and Western blotting respectively. The growth of QBC939 cells was detected by using colony-forming growth assays. Cell proliferation activity was detected by methyl thiazol tetrazolium(MTT). Cell cycle and apoptosis of cells were analyzed by flow cytometry(FCM). The expression of apoptosis-related protein, cysteinyl aspartate-specific protease-3(Caspase-3)and B cell lymphoma/leukemia-2(bcl-2) was detected by Western blotting. Results Compared to the control plasmids, RT-qPCR showed the mRNA expression of decorin in the pEGFP-DCN plasmids was increased by 32.34 fold.Western blotting showed the protein expression of decorin was increased by 2 fold. The growth of QBC939 cells was inhibited in cells transfected with pEGFP-DCN as compared to the empty vector. MTT assay showed a decrease of QBC939 cells proliferation in cells transfected with pEGFP- DCN as compared to the empty vector. Cell cycle analysis presented an obvious cell- cycle arrest at the G1-G0 phase and a decreased G2- S phase in cells transfected with pEGFP- DCN as compared to the negative control group. Flow cytometry detected an increase of the apoptotic cells in cells treated with pEGFP-DCN as compared to the empty vector.Western blotting identified that cleaved Caspase- 3 was significantly increased,and bcl- 2 was decreased in cells transfected with pEGFP- DCN(0.787±0.068 vs.1.276±0.157). Conclusion The overexpression of DCN gene could significantly promote the proliferation of cholangiocarinoma cells, which may be associated with the overexpression of Caspase-3 and downexpression of bcl-2. Key words: Cholangiocarcinoma; Decorin; Cell cycle; Apoptosis

Decorin is responsible for progression of non-small-cell lung cancer by promoting cell proliferation and metastasis.

Decorin, a member of the small leucine-rich proteoglycans family, exists and plays multifunctional roles in stromal and epithelial cells. Emerging evidences showed that decorin is dysregulated expression in a wide variety of human tumors and affects a broad biology process of cancer cells, including growth, metastasis, and angiogenesis. Recent studies demonstrated that decorin could affect A549 proliferation though decreasing TGF-β1, cycling D1 expression and increasing P53 and P21 expression. However, limited data are available on the effect of decorin on metastasis of non-small-cell lung cancer (NSCLC) cell lines and how decorin impacts metastasis is still unknown. In this study, we identified decorin mRNA expression through Oncomine database and verified the expression of decorin mRNA and protein in 50 patients who underwent primary surgical resection of a NSCLC in the Department of Thoracic Surgery, Jinling Hospital, Nanjing University School of Medicine, China, between September 2013 and March 2014 by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blot. Also, the correlationship between decorin and the NSCLC patients' clinical characteristics or survival ( www.kmplot.com ) was analyzed. Via ectopic expression analyses and Western blot, the roles of decorin in proliferation, metastasis, and the underline mechanism for decorin expression were further explored. We found that decorin was downregulated in NSCLC tissues compared with the adjacent normal lung tissues or normal tissues. Additionally, the expression of decorin was correlated with tumor size, lymph node metastasis, tumor stage, and prognosis. We also showed that overexpression of decorin could inhibit NSCLC cell lines proliferation and metastasis. Through Western blot analysis, we identified that E-cadherin and vascular endothelial growth factor (VEGF) are two key factors responsible for the growth arrest and metastasis inhibition induced by decorin in NSCLC. Our results indicated that decorin plays crucial roles in NSCLC against carcinogenesis and progression. Decorin might be a predictive factor and an attractive therapeutic target for NSCLC patients.

Reciprocity in breast cancer progression.

Reciprocity in breast cancer progression.

Proteoglycan Expression Is Influenced by Mechanical Load in TMJ Discs

The expression and assembly of the extracellular matrix are profoundly associated with adaptive and pathological responses of the temporomandibular joint (TMJ). To better understand the adaptive responses of the TMJ disc to mechanical loading, we examined the expression of 2 modular proteoglycans and 10 small leucine-rich proteoglycans (SLRPs) at the mRNA and protein levels and determined the contents of proteoglycan-related glycosaminoglycans (GAGs) in rat TMJ discs in response to altered mechanical loading caused by an incisal bite plane. One hundred thirty 7-week-old male Wistar rats were assigned to control and bite plane groups. TMJ disc thickness and the intensity of toluidine blue staining of metachromasia increased in the posterior band after 2 weeks of wearing the bite plane. GAG content increased significantly in the bite plane group after 2 weeks. Quantitative real-time RT-PCR (reverse transcription polymerase chain reaction) analysis indicated that biglycan and chondroadherin mRNA levels increased after 2 weeks and that the level of decorin mRNA increased at 4 weeks. Versican mRNA levels increased after 3 weeks, particularly for the V0 and V1 versican isoforms, which carry more GAG attachment sites than do the V2 and V3 isoforms. Western analysis demonstrated a corresponding increase in the levels of versican, biglycan, and decorin core proteins at 4 weeks in the bite plane group. These results indicate that mechanical loading differentially influences proteoglycan mRNA expression and protein accumulation in the TMJ disc. The change in proteoglycan mRNA and protein levels may lead to the modulation of matrix–matrix and cell–matrix interactions and has important biological significance for adaptation to complicated biomechanical requirements and for tissue maintenance in the TMJ disc.

Expression of decorin throughout the murine hair follicle cycle: hair cycle dependence and anagen phase prolongation.

Decorin is a prototypical member of the small leucine-rich proteoglycan (SLRP) family, which is involved in numerous biological processes. The role of decorin, as a representative SLRP, in hair follicle morphogenesis has not been elucidated. We present our initial findings on decorin expression patterns during induced murine hair follicle (HF) cycles. It was found that decorin expression is exclusively restricted to the epidermis, outer root sheath and sebaceous glands during the anagen phase, which correlates with the upregulation of decorin mRNA and protein expression in depilated murine dorsal skin. Furthermore, we used a functional approach to investigate the effects of recombinant human decorin (rhDecorin) via cutaneous injection into HFs at various murine hair cycle stages. The local injection of rhDecorin (100 μg/ml) into the hypodermis of depilated C57BL/6 mice at anagen delayed catagen progression. In contrast, rhDecorin injection during the telogen phase caused the premature onset of anagen, as demonstrated by the assessment of the following parameters: (i) hair shaft length, (ii) follicular bulbar diameter, (iii) hair follicle cycling score and (iv) follicular phase percentage. Taken together, our results suggest that decorin may modulate follicular cycling and morphogenesis. In addition, this study also provides insight into the molecular control mechanisms governing hair follicular epithelial-mesenchymal interactions.

Methylated +58CpG site decreases DCN mRNA expression and enhances TGF-β/Smad signaling in NSCLC cells with high metastatic potential

Decorin (DCN) has been suggested to display an anti-metastatic role by antagonizing bioactive TGF-β in advanced human cancers. However, the epigenetic mechanisms by which defective expression of DCN causes cancer metastasis remain unclear. We focused on non-small cell lung cancer (NSCLC) cell lines with low metastatic potential (95C) and high metastatic potential (95D), which share a similar genetic background. Quantitative PCR and clonal bisulfite sequencing indicated that the methylation levels of the +58CpG site in the DCN 5'-UTR region was significantly higher in 95D cells with low expression of DCN mRNA compared to 95C cells with high expression of DCN mRNA. In silico prediction and ChIP assay showed a correlation between +58CpG site and AhR, which was reported as a transcriptional activator. Importantly, EMSA and luciferase reporter gene assays suggested that +58CpG methylation specifically diminished the recruitment of AhR to DCN 5'-UTR sequence and caused a reduction of approximately50% in transcriptional activity. At baseline, 95D cells exhibited higher p-Smad3 levels and lower E-cadherin expression when compared with 95C cells. The demethylating agent 5-Aza significantly led to restoration of DCN expression, reduced level of p-Smad3, increased expression of E-cadherin in 95D cells. Taken together, we identified the methylated +58CpG in DCN 5'-UTR associated with reduced expression of DCN mRNA, and revealed that +58CpG methylation may be one of the mechanisms accounting for reduced recruitment of the transcriptional activator AhR to DCN 5'-UTR, and suggest that this mechanism promotes TGF-β/Smad signaling by enhancing the phosphorylation of Smad3, thereby downregulating E-cadherin in NSCLC cells with high metastatic potential.

Role Of Decorin In Multiple Myeloma (MM) Bone Marrow Microenvironment

Decorin is a small leucine rich proteoglycan found in the extracellular matrix of various connective tissues with potential effective tumor suppressor properties. Recently, it has been shown that decorin decreases in multiple myeloma (MM) patients compared to healthy volunteers, and also in patients with osteolytic bone lesions than non-osteolytic lesions. By using a cytokine array analysis we showed that decorin is down regulated in patients withdrawn from aminobisphosphanates for six months. These results led us to focus on decorin and its role in the bone marrow micro environment.We looked at the expression of decorin in MM cell lines. The mRNA expression of decorin in MM cells (OPM1, OPM2, RPMI, INA6, U266, KMS18 and KMS20) was not detectable when compared to MG63, an osteosarcoma cell line that constitutively produces decorin. Consistent with the mRNA expression, decorin protein secretion was also very low in the MM cell lines as demonstrated by ELISA. A 48 hour MTT assay on OPM1, OPM2, RPMI, MM1.S and CD138+ patient myeloma cells with increasing concentrations (0, 5, 10, 20 and 40μg/ml) of exogenous decorin did not show a significant decrease in cell viability. These results indicate that decorin is not produced by MM cells and does not have a direct effect on MM cell viability.Having looked at decorin in the tumor, we then observed its expression in the stromal compartment. We investigated decorin mRNA and protein expression in bone marrow stromal cells (BMSC), osteoclasts (OC) and osteoblats (OB) differentiated from MM patients. BMSC and OB, differentiated for 4 and 7 days, showed a significantly higher expression of decorin compared to the OC. Decorin secretion was more pronounced by differentiating OB than BMSCs. Consistent with previously reported data, we also found that decorin protein levels were higher in BMSCs and OB differentiated for 4 and 7 days from healthy volunteers than MM patients. Moreover, addition of exogenous decorin (at 5 and 10 μg/ml) to OB increased OB differentiation as seen by increased mRNA expression for markers of OB differentiation (alkaline phosphatase and RUNX2) suggesting that decorin plays a role in OB differentiation.Given the significance of the interaction between the MM tumor and its micro-environment we next evaluated the effect of decorin in the stroma when co-cultured with MM cells. Decorin mRNA levels were down regulated when OPM2 cells were co-cultured without direct cell contact with BMSC and OB differentiated for 4 and 7 days suggesting that MM cells decreased decorin and the effect is probably cytokine mediated.Having studied the effect of decorin on OB in the stromal compartment, we then focused on the OCs. When exogenous decorin was added at 5 and 10mg/ml to peripheral blood mononuclear cells from MM patients in OC differentiation media for 7, 14 and 21 days of differentiation, there was a significant decrease in OC number as observed by TRAP staining (80% decrease in OC number in 5mg/ml and 95% decrease in 10mg/ml compared to control). Decorin at the same concentrations greatly decreased the area of pits as compared to the control (43% decrease in area of pit in 5mg/ml and 67% decrease in 10mg/ml compared to control) suggesting that exogenous decorin inhibited OC differentiation and function. TRAP staining and MTT assays on 14 day mature OCs with decorin treated for 48 hours after maturation, did not show a decrease in cell number and viability of OC indicating that decorin does not affect mature OCs.In conclusion, our data suggests that decorin secreted by stromal cells and in particular differentiating OBs, does not directly affect the viability of MM cells. It inhibits OC differentiation and function and promotes OB differentiation. Importantly, decorin levels decreased significantly in the BMSC and OB when co-cultured with MM cells. We speculate that this decrease is a result of decreased OB differentiation by MM cells. Since, all the above lines of evidence point to decorin modulating the myeloma microenvironment with potential indirect anti-tumor effects without acting as a direct antagonist to the tumor, ongoing studies that understand mechanisms to stimulate decorin secretion can prove to be useful with respect to MM microenvironment interactions. Disclosures:Raje:Celgene: Consultancy, Research Funding; Millenium: Consultancy, Research Funding; Onyx: Consultancy, Research Funding; Amgen: Consultancy; Acetylon: Consultancy, Research Funding; Eli Lilly: Research Funding.

Lack of Decorin Expression by Human Bladder Cancer Cells Offers New Tools in the Therapy of Urothelial Malignancies

Decorin, a multifunctional small leucine-rich extracellular matrix proteoglycan, has been shown to possess potent antitumour activity. However, there is some uncertainty whether different cancer cells express decorin in addition to non-malignant stromal cells. In this study we clarified decorin expression by human bladder cancer cells both in vivo and in vitro. In addition, the effect of adenovirus-mediated decorin expression on human bladder cancer cells in vitro was examined. We first demonstrated using the publicly available GeneSapiens databank that decorin gene expression is present in both normal and malignant human bladder tissues. However, when we applied in situ hybridization with digoxigenin-labeled RNA probes for decorin on human bladder carcinoma tissue samples derived from a large radical cystectomy patient cohort (n = 199), we unambiguously demonstrated that invasive and non-invasive bladder carcinoma cells completely lack decorin mRNA. The cancer cells were also negative for decorin immunoreactivity. Instead, decorin expression was localized solely to original non-malignant stromal areas of bladder tissue. In accordance with the aforementioned results, human bladder cancer cells in vitro were also negative for decorin expression as shown by RT-qPCR analyses. The lack of decorin expression by bladder cancer cells was shown not to be due to the methylation of the proximal promoter region of the decorin gene. When bladder cancer cells were transfected with a decorin adenoviral vector, their proliferation was significantly decreased. In conclusion, we have shown that human bladder cancer cells are totally devoid of decorin expression. We have also shown that adenovirus-mediated decorin gene transduction of human bladder cancer cell lines markedly inhibits their proliferation. Thus, decorin gene delivery offers new potential therapeutic tools in urothelial malignancies.

Human renal stem/progenitor cells repair tubular epithelial cell injury through TLR2-driven inhibin-A and microvesicle-shuttled decorin

Acute kidney injury (AKI) is emerging as a worldwide public health problem. Recent studies have focused on the possibility of using human adult renal stem/progenitor cells (ARPCs) to improve the repair of AKI. Here we studied the influence of ARPCs on the healing of cisplatin-injured renal proximal tubular epithelial cells. Tubular, but not glomerular, ARPCs provided a protective effect promoting proliferation of surviving tubular cells and inhibiting cisplatin-induced apoptosis. The recovery effect was specific to tubular ARPCs, occurred only after damage sensing, and was completely cancelled by TLR2 blockade on tubular ARPCs. Moreover, tubular, but not glomerular, ARPCs were resistant to the apoptotic effect of cisplatin. Tubular ARPCs operate mainly through the engagement of TLR2, the secretion of inhibin-A protein, and microvesicle-shuttled decorin, inhibin-A, and cyclin D1 mRNAs. These factors worked synergistically and were essential to the repair process. The involvement of tubular ARPC-secreted inhibin-A and decorin mRNA in the pathophysiology of AKI was also confirmed in transplant patients affected by delayed graft function. Hence, identification of this TLR2-driven recovery mechanism may shed light on new therapeutic strategies to promote the recovery capacity of the kidney in acute tubular damage. Use of these components, derived from ARPCs, avoids injecting stem cells.

Multi-unit sustained vibration loading platform for biological tissues: Design, validation and experimentation

The relationships between mechanical inputs and resulting biological tissue structure, composition, and metabolism are critical to detailing the nuances of tissue mechanobiology in both healthy and injured tissues. Developing a model system to test the mechanobiology of tissues ex-vivo is a complex task, as controlling chemical and mechanical boundary layers in-vitro are difficult to replicate. A novel multi-unit vibration loading platform for intervertebral discs was designed and validated with both independent electronic data and experimental loading of 6 bovine intervertebral discs (IVDs) and an equal number of unloaded controls. Sustained vibration was applied using closed-loop positional control of pushrods within four independent bioreactors with circulating phosphate buffered saline. The bioreactors were designed to be modular with removable components allowing for easy cleaning and replacement. The loading regime was chosen to maximize target mRNA expression as reported in previous research. Aggrecan, decorin, and versican mRNA all reported statistically significant increases above control levels. Biglycan, collagen type I and II showed no significant difference from the control group. Further study is required to determine the resulting effect of increased mRNA expressions on long-term disc health. However these results indicate that this research is past the proof of concept stage, supporting future studies of mechanobiology utilizing this new device. The next stage in developing this novel loading platform should consider modifying the tissue grips to explore the effects of different directional loading on different gene expression, and also loading different types of tissues.

Expression of small leucine-rich proteoglycans in rat anterior pituitary gland

Proteoglycans are components of the extracellular matrix and comprise a specific core protein substituted with covalently linked glycosaminoglycan chains. Small leucine-rich proteoglycans (SLRPs) are a major family of proteoglycans and have key roles as potent effectors in cellular signaling pathways. Research during the last two decades has shown that SLRPs regulate biological functions in many tissues such as skin, tendon, kidney, liver, and heart. However, little is known of the expression of SLRPs, or the characteristics of the cells that produce them, in the anterior pituitary gland. Therefore, we have determined whether SLRPs are present in rat anterior pituitary gland. We have used real-time reverse transcription with the polymerase chain reaction to analyze the expression of SLRP genes and have identified the cells that produce SLRPs by using in situ hybridization with a digoxigenin-labeled cRNA probe. We have clearly detected the mRNA expression of SLRP genes, and cells expressing decorin, biglycan, fibromodulin, lumican, proline/arginine-rich end leucine-rich repeat protein (PRELP), and osteoglycin are located in the anterior pituitary gland. We have also investigated the possible double-staining of SLRP mRNA and pituitary hormones, S100 protein (a marker of folliculostellate cells), desmin (a marker of capillary pericytes), and isolectin B4 (a marker of endothelial cells). Decorin, biglycan, fibromodulin, lumican, PRELP, and osteoglycin mRNA have been identified in S100-protein-positive and desmin-positive cells. Thus, we conclude that folliculostellate cells and pericytes produce SLRPs in rat anterior pituitary gland.

Adverse cardiac remodelling in spontaneously hypertensive rats: acceleration by high aerobic exercise intensity

In the present study it was hypothesized that voluntary aerobic exercise favours a pro-fibrotic phenotype and promotes adverse remodelling in hearts from spontaneously hypertensive rats (SHRs) in an angiotensin II-dependent manner. To test this, female SHRs at the age of 1 year were started to perform free running wheel exercise. Captopril was used to inhibit the renin-angiotensin system (RAS). Normotensive rats and SHRs kept in regular cages were used as sedentary controls. Training intensity, expressed as mean running velocity, was positively correlated with the left ventricular mRNA expression of TGF-β(1), collagen-III and biglycan but negatively correlated with the ratio of sarcoplasmic reticulum Ca(2+)-ATPase (SERCA)2a to Na(+)-Ca(2+) exchanger (NCX). A pro-fibrotic phenotype was verified by Picrosirius red staining. Sixty-seven per cent of SHRs performing free running wheel exercise died either spontaneously or had to be killed during a 6 month follow-up. In the presence of captopril, aerobic exercise did not show a similar positive correlation between training intensity and the expression of fibrotic markers. Moreover, in SHRs receiving captopril and performing free running wheel exercise, a training intensity-dependent reverse remodelling of the SERCA2a-to-NCX ratio was observed. None of these rats died spontaneously or had to be killed. In captopril-treated SHRs performing exercise, expression of mRNA for decorin, a natural inhibitor of TGF-β(1), was up-regulated. Despite these differences between SHR-training groups with and without captopril, positive training effects (lower resting heart rate and no progression of hypertension) were found in both groups. In conclusion, high aerobic exercise induces an angiotensin II-dependent adverse remodelling in chronic pressure overloaded hearts. However, high physical activity can potentially induce reverse remodelling in the presence of RAS inhibition.