Decorin Concentrations Research Articles

Decorin, an exercise-induced secretory protein, is associated with improved prognosis in breast cancer patients but does not mediate anti-tumorigenic tissue crosstalk in mice

BackgroundRegular exercise can reduce incidence and progression of breast cancer, but the mechanisms for such effects are not fully understood. MethodsWe used a variety of rodent and human experimental model systems to determine whether exercise training can reduce tumor burden in breast cancer and to identify mechanism associated with any exercise training effects on tumor burden. ResultsWe show that voluntary wheel running slows tumor development in the mammary specific polyomavirus middle T antigen overexpression (MMTV-PyMT) mouse model of breast cancer but only when mice are not housed alone. We identify the proteoglycan decorin as a contraction-induced secretory factor that systemically increases in patients with breast cancer immediately following exercise. Moreover, high expression of decorin in tumors is associated with improved prognosis in patients, while treatment of breast cancer cells in vitro with decorin reduces cell proliferation. Notwithstanding, when we overexpressed decorin in murine muscle or injected recombinant decorin systemically into mouse models of breast cancer, elevated plasma decorin concentrations did not result in higher tumor decorin levels and tumor burden was not improved. ConclusionExercise training is anti-tumorigenic in a mouse model of luminal breast cancer, but the effect is abrogated by social isolation. The proteoglycan decorin is an exercise-induced secretory protein, and tumor decorin levels are positively associated with improved prognosis in patients. The hypothesis that elevated plasma decorin is a mechanism by which exercise training improves breast cancer progression in humans is not, however, supported by our pre-clinical data since elevated circulating decorin did not increase tumor decorin levels in these models.

The decorin and myostatin response to acute whole body vibration: impact of adiposity, sex, and race.

Traditional forms of exercise affect immune, metabolic, and myokine responses and contribute to a multitude of health benefits. Whole body vibration (WBV) has recently emerged as an exercise mimetic that may be more tolerable for those individuals that cannot perform traditional exercise. However, the myokines response to acute WBV in humans has yet to be fully elucidated. To characterize the decorin and myostatin response to acute whole body vibration (WBV) and determine the impact of adiposity, sex, and race. One hundred twenty-nine adults (32.8 ± 0.4 years, 66.7% female, 53.5% non-Hispanic Black) were recruited as part of an ongoing, longitudinal twin cohort parent study. Participants were classified into three groups: those with obesity (OB: ≥30 kg/m2), those who are overweight (OW: ≥25 and <30 kg/m2), or those with normal weight (NW: <25 kg/m2) based on BMI. Blood was collected at baseline (PRE), immediately post (POST), and 1 h (1H), 3 h (3H), and 24 h (24H) post WBV. The acute WBV protocol consisted of 10 cycles of 1 min of vibration exercise followed by 30 s of standing rest. The response was similar between NW and OW, so these groups were combined for analysis (NW/OW: BMI < 30 kg/m2). Overall, circulating concentrations of decorin were higher (p < 0.001) POST (8.80 ± 0.19 pg/mL) and significantly lower (p's ≤ 0.005) at 1H (8.66 ± 0.19 pg/mL) and 3H (8.68 ± 0.19 pg/mL), compared to PRE (8.71 ± 0.19 pg/mL). Decorin POST was greater (p = 0.016) in the OB group (8.82 ± 0.18 pg/mL) compared to the NW/OW group (8.77 ± 0.20 pg/mL). Overall, myostatin was higher (p = 0.002) POST (54.93 ± 1.04 pg/mL) and lower (p < 0.001) at 24H (49.13 ± 1.04 pg/mL) compared to PRE (53.49 ± 1.04 pg/mL). The myostatin response was lower (p's ≤ 0.001) in female and non-Hispanic White individuals compared to male and non-Hispanic Black individuals, respectively. A single bout of WBV can facilitate the release of decorin and myostatin into circulation, a similar response to traditional exercise. Additionally, adiposity, sex and race should be considered when evaluating the myokines response to WBV.

Comparative Analysis of Myokines and Bone Metabolism Markers in Prepubertal Vegetarian and Omnivorous Children.

The role of bone and muscle as endocrine organs may be important contributing factors for children's growth and development. Myokines, secreted by muscle cells, play a role in regulating bone metabolism, either directly or indirectly. Conversely, markers of bone metabolism, reflecting the balance between bone formation and bone resorption, can also influence myokine secretion. This study investigated a panel of serum myokines and their relationships with bone metabolism markers in children following vegetarian and omnivorous diets. A cohort of sixty-eight healthy prepubertal children, comprising 44 vegetarians and 24 omnivores, participated in this study. Anthropometric measurements, dietary assessments, and biochemical analyses were conducted. To evaluate the serum concentrations of bone markers and myokines, an enzyme-linked immunosorbent assay (ELISA) was used. The studied children did not differ regarding their serum myokine levels, except for a higher concentration of decorin in the vegetarian group (p = 0.020). The vegetarians demonstrated distinct pattern of bone metabolism markers compared to the omnivores, with lower levels of N-terminal propeptide of type I procollagen (P1NP) (p = 0.001) and elevated levels of C-terminal telopeptide of type I collagen (CTX-I) (p = 0.018). Consequently, the P1NP/CTX-I ratio was significantly decreased in the vegetarians. The children following a vegetarian diet showed impaired bone metabolism with reduced bone formation and increased bone resorption. Higher levels of decorin, a myokine involved in collagen fibrillogenesis and essential for tissue structure and function, may suggest a potential compensatory mechanism contributing to maintaining bone homeostasis in vegetarians. The observed significant positive correlations between myostatin and bone metabolism markers, including P1NP and soluble receptor activator of nuclear factor kappa-B ligand (sRANKL), suggest an interplay between muscle and bone metabolism, potentially through the RANK/RANKL/OPG signaling pathway.

Silk protein sericin: a promising therapy for Achilles tendinopathy-evidence from an experimental rat model.

This study investigated the efficacy of sericin in treating experimental Achilles tendinopathy (AT) in rats via the transforming growth factor-beta (TGF-β)/mothers against decapentaplegic (Smad) pathway compared with diclofenac sodium (DS). An AT model was induced in rats using collagenase enzyme type I and divided into 5 groups: C (control), AT (diseased control), ATS (AT treated with sericin), ATN (AT treated with DS), and ATSN (AT treated with sericin and DS). Sericin injection was given on the 3rd and 6th days by intratendinous injection (0.8 g/kg/mL), and DS was administered for 14 days by oral gavage (1.1 mg/kg/day). Serum concentrations of total oxidant-antioxidant status (TOS-TAS), TGF-β1, decorin, Smad2, and connective tissue growth factor (CTGF) were measured. Histopathologic and immunohistochemical (IHC) studies were conducted on Achilles tendon samples. The TOS, oxidative stress index (OSI), TGF-β1, Smad2, CTGF, and decorin serum concentrationswere significantly higher in AT than in C and significantly lower in ATS than in AT (P<0.05). Histopathological examination revealed that irregular fibers, degeneration, and round cell nuclei were significantly elevated in AT. Spindle-shaped fibers were similar to those in C, and degeneration was reduced in ATS. TGF-β1 and Smad2/3 expression was increased, and collagen type I alpha-1 (Col1A1) expression was decreased in AT vs. C (P=0.001). In the ATS, TGF-β1 and Smad2/3 expression decreased, and Col1A1 expression increased. The Bonar score significantly increased in the AT group (P =0.001) and significantly decreased in the ATS group (P =0.027). Sericin shows potential efficacy in reducing oxidative stress and modulating the TGF-β/Smad pathway in experimental AT models in rats. It may be a promising therapeutic agent for AT, warranting further clinical studies for validation. Key Points • This study revealed that sericin mitigates AT-induced damagethrough the TGF-β/Smad pathway in an AT rat model. • ELISA and IHC investigations corroborated the effectiveness ofsericin via the pivotal TGF-β/Smad pathway in tissue repair. • Evidence indicates that sericin enhances collagen synthesis,shapes tendon fiber structure, and diminishes histopathologicaldegeneration. • Sericin's antioxidant properties were reaffirmed in its AT treatmentapplication.

Decorin Concentrations in Aqueous Humor of Patients with Diabetic Retinopathy.

Diabetic retinopathy (DR) is a microvascular complication of diabetes in the retina. Chronic hyperglycemia damages retinal microvasculature embedded into the extracellular matrix (ECM), causing fluid leakage and ischemic retinal neovascularization. Current treatment strategies include intravitreal anti-vascular endothelial growth factor (VEGF) or steroidal injections, laser photocoagulation, or vitrectomy in severe cases. However, treatment may require multiple modalities or repeat treatments due to variable response. Though DR management has achieved great success, improved, long-lasting, and predictable treatments are needed, including new biomarkers and therapeutic approaches. Small-leucine rich proteoglycans, such as decorin, constitute an integral component of retinal endothelial ECM. Therefore, any damage to microvasculature can trigger its antifibrotic and antiangiogenic response against retinal vascular pathologies, including DR. We conducted a cross-sectional study to examine the association between aqueous humor (AH) decorin levels, if any, and severity of DR. A total of 82 subjects (26 control, 56 DR) were recruited. AH was collected and decorin concentrations were measured using an enzyme-linked immunosorbent assay (ELISA). Decorin was significantly increased in the AH of DR subjects compared to controls (p = 0.0034). AH decorin levels were increased in severe DR groups in ETDRS and Gloucestershire classifications. Decorin concentrations also displayed a significant association with visual acuity (LogMAR) measurements. In conclusion, aqueous humor decorin concentrations were found elevated in DR subjects, possibly due to a compensatory response to the retinal microvascular changes during hyperglycemia.

Nordic Walking Rather Than High Intensity Interval Training Reduced Myostatin Concentration More Effectively in Elderly Subjects and the Range of This Drop Was Modified by Metabolites of Vitamin D.

The COVID-19 pandemic and subsequent self-isolation exacerbated the problem of insufficient amounts of physical activity and its consequences. At the same time, this revealed the advantage of vitamin D. Thus, there was a need to verify the effects of those forms of training that can be performed independently. In this study, we examined the effects of Nordic walking (NW) and high intensity interval training (HIIT) with regard to the impact of the metabolite vitamin D. We assigned 32 overweight adults (age = 61 ± 12 years) to one of two training groups: NW = 18 and HIIT = 14. Body composition assessment and blood sample collection were conducted before starting the training programs and a day after their completion. NW training induced a significant decrease in myostatin (p = 0.05) concentration; however, the range was dependent on the baseline concentrations of vitamin D metabolites. This drop was accompanied by a significant negative correlation with the decorin concentration. Unexpectedly, NW caused a decrement in both forms of osteocalcin: undercarboxylated (Glu-OC) and carboxylated-type (Gla-OC). The scope of Glu-OC changes was dependent on a baseline concentration of 25(OH)D2 (r = −0.60, p = 0.01). In contrast, the HIIT protocol did not induce any changes. Overall results revealed that NW diminished the myostatin concentration and that this effect is more pronounced among adults with a sufficient concentration of vitamin D metabolites.

Plasma Levels of Decorin Increased in Patients during the Progression of Breast Cancer.

Decorin (DCN), an extracellular matrix proteoglycan found in tumor surrounding tissues, is a natural inhibitor of tumor cell proliferation and invasion. We conducted a cross-sectional observation study to evaluate the association of the pathological stage with the levels of DCN in plasma or tumor surrounding tissue. Among 118 patients who underwent breast surgery, 35 were designated as carcinoma in situ (Stage 0), 39 were Stage I, and 44 were Stage II or III. The stromal expression of DCN was quantified using a semiquantitative digital image analysis after immunohistochemical staining. The concentration of DCN was evaluated with a specific ELISA. As we have previously shown, stromal DCN expression was attenuated in the patients with Stage I, whereas stromal and plasma DCN was elevated paradoxically in those with Stage II/III. The elevated plasma DCN is an independent predictive factor of Stage II/III by the multivariate logistic regression analysis. The plasma level of DCN was negatively correlated with stromal DCN expression only in patients with advanced disease (Stage II/III). The plasma level of DCN could become a useful biomarker for patients in the advanced stages. Extensive studies and further assessments are warranted for evaluating the prognostic significance and tumor characteristics to understand the clinical significances of stromal and systemic DCN.

Plasma Activin A and Decorin in Exercised Purebred Arabian Horses – Preliminary Study

Development of the musculoskeletal system occurs, in part, through an impact on regulatory proteins, such as activin A and decorin. Activin A induces atrophic effects on skeletal muscle, and decorin regulates the formation of connective tissue proteins like collagen and elastin in tendons and ligaments. The aim of this study was to evaluate the influence of different intensities of exercise on blood plasma activin A and decorin concentrations in horses. Ten young purebred Arabian horses were subjected to routine training sessions on a racetrack, and another 11 adult horses of the same breed participated in endurance rides. Race horses were examined during gallop tests over a distance of 1200 m and endurance horses at distances from 20 to 80 km. Blood samples were collected at rest and after exercise to determine plasma concentrations of activin A, decorin and cortisol. Despite differences in the intensity of exercise, the plasma decorin concentration remained unchanged, and activin A tended to decrease in endurance horses only. The exercise-induced changes in plasma activin A concentrations correlated with the covered distance (r = -0.43; P < .05), but not with the changes in cortisol values. Further studies are needed to confirm the usefulness of plasma activin A as a potential indicator of a horse's endurance performance.

Decorin concentrations in canine normal and neoplastic mammary gland tissues.

In the present study, the concentration of decorin in canine normal and neoplastic mammary gland tissues was examined to understand the potential role of decorin in development and progression of canine mammary tumours. The homogenates of 48 mammary gland tumours (10 benign and 38 malignant) and 10 samples of normal canine mammary gland tissue were used in the study. The presence and quantification of decorin was examined in the homogenates using Western blot and specific canine ELISA. Western blotting confirmed the presence of decorin both in the normal mammary gland tissues and in the mammary gland tumours. The concentration of decorin was significantly higher (p<.05) in the benign tumours and non-metastatic malignant tumours than in the normal mammary gland. The concentration of decorin was significantly lower (p<.05) in the malignant tumours with metastasis to regional lymph nodes compared with benign tumours and non-metastatic malignant tumours. No significant differences were found in the level of decorin between the benign and the non-metastatic malignant tumours. Both the histological type of malignant tumours and the histological grade did not significantly affect the concentration of decorin. These findings suggest that neoplastic transformation in the canine mammary gland leads to increase in the decorin protein synthesis. The reducing decorin concentration in canine malignant mammary tumours appears to facilitate the metastatic spread of these tumours.

Age-related changes of tendon fibril micro-morphology and gene expression.

Aging is hypothesized to be associated with changes in tendon matrix composition which may lead to alteration of tendon material properties and hence propensity to injury. Altered gene expression may offer insights into disease pathophysiology and thus open new perspectives toward designing pathophysiology‐driven therapeutics. Therefore, the current study aimed at identifying naturally occurring differences in tendon micro‐morphology and gene expression of newborn, young and old horses. Age‐related differences in the distribution pattern of tendon fibril thickness and in the expression of the tendon relevant genes collagen type 1 (Col1), Col3, Col5, tenascin‐C, decorin, tenomodulin, versican, scleraxis and cartilage oligomeric matrix protein were investigated. A qualitative and quantitative gene expression and collagen fibril diameter analysis was performed for the most frequently injured equine tendon, the superficial digital flexor tendon, in comparison with the deep digital flexor tendon. Most analyzed genes (Col1, Col3, Col5, tenascin‐C, tenomodulin, scleraxis) were expressed at a higher level in foals (age ≤ 6 months) than in horses of 2.75 years (age at which flexor tendons become mature in structure) and older, decorin expression increased with age. Decorin was previously reported to inhibit the lateral fusion of collagen fibrils, causing a thinner fibril diameter with increased decorin concentration. The results of this study suggested that reduction of tendon fibril diameters commonly seen in equine tendons with increasing age might be a natural age‐related phenomenon leading to greater fibril surface areas with increased fibrillar interaction and reduced sliding at the fascicular/fibrillar interface and hence a stiffer interfascicular/interfibrillar matrix. This may be a potential reason for the higher propensity to tendinopathies with increasing age.

The inhibitory effect of decorin on apoptosis of human lens epithelial cells under high glucose condition and its mechanism

Objective To investigate the effects of decorin (DCN) on apoptosis and oxidative stress in human lens epithelial cells (LECs) under high glucose condition. Methods HLE-B3 cells were cultured in vitro and the effect of DCN with different concentrations on HLE-B3 viability was determined by using cell counting kit-8 (CCK-8). The cultured cells were divided into normal control group, DCN group, high glucose group and DCN + high glucose group.Flow cytometry was used to detect the apoptosis rate and the expression of reactive oxygen species (ROS) in the cells.Microplate spectrophotometer was used to measure total superoxide dismutase (SOD) enzyme activity and the radio of glutathione (GSH)/glutathione disulfide (GSSG). Western blot was used to detect the expressions of bax and bcl-2 proteins. Results HLE-B3 cells were spindle shaped, with centered and clearly visible nuclei and neatly cell arrangment.According to CCK-8 method, survival rates of HLE-B3 in all groups were more than 90%.Different concentrations of DCN showed no significant effect on HLE-B3 survival rate (all at P>0.05). After 48 hours of cell culture, the apoptosis rate of high glucose group was significantly higher than that of normal control group, and the apoptosis rate of DCN+ high glucose group was significantly lower than that of high glucose group (both at P=0.000). The mean fluorescence intensity of intracellular ROS in the high-glucose group was significantly higher than that in the normal control group, and the mean fluorescence intensity of ROS in the DCN group was significantly higher than that in the high glucose group (both at P=0.000). The total SOD activity in the high glucose group was significantly lower than that in the normal control group and DCN group (P=0.007, 0.004). The GSH/GSSG ratio of the high-glucose group was significantly lower than that of the normal control group and DCN group (both at P=0.000). Conclusions DCN can inhibit the apoptosis and oxidative stress of HLE-B3 under high glucose, which provides the basis for the treatment of diabetic cataract. Key words: Decorin; Human lens epithelial cell; High glucose condition; Oxidative stress; Apoptosis; Inhibitory effect; Mechanism

Association of matrix metalloproteinase-9 and decorin expression with the infiltration of cervical cancer.

Matrix metalloproteinase-9 (MMP9) has been recognized to be an important factor in cancer invasion and metastasis. In contrast, decorin has been revealed to inhibit primary tumor development. The aim of the present study was to investigate the function of MMP9 and decorin in cervical cancer. Three experiments were performed to analyze the function of MMP9 and decorin in the invasion of cervical cancer by: i) Analyzing the expression of MMP9 and decorin by immunohistochemistry in 100 cervical specimens; ii) determining the concentration of decorin by an enzyme-linked immunosorbent assay (ELISA) using the human squamous cervical cancer cell line CaSki and human endometrial stromal cell line CRL4003 and iii) evaluating the invasion ability of CaSki cells in a cervical invasion model by an invasion assay. Immunohistochemistry revealed that MMP9 was overexpressed in microinvasive carcinoma (100.0%) but was less strongly expressed in normal or pre-malignant squamous epithelium (0-41.9%). In contrast, the activity of decorin in stroma adjacent to neoplastic cells was lower in microinvasive carcinoma (9.1%) compared with in normal or pre-malignant lesions (74.2-100.0%). An ELISA revealed that MMP9 released from CaSki cells resolved the decorin released from CRL4003 cells. An invasion assay demonstrated that the invasive ability of CaSki cells was suppressed by an MMP inhibitor, and decorin was released from CRL4003 cells. These data suggested that decorin prevented the invasion of malignant cells in uterine cervical cancer; however, MMP9 promotes cell invasion by destroying decorin.

Altered Decorin Biology in Proliferative Vitreoretinopathy: A Mechanistic and Cohort Study.

To determine if vitreous levels of the pro-fibrotic cytokine transforming growth factor beta2 (TGF-β2) and its opposing regulator decorin predict subsequent proliferative vitreoretinopathy (PVR) development in patients with rhegmatogenous retinal detachment (RRD). We examined the effect of TGF-β2 and decorin on epithelial-mesenchymal transition (EMT) and collagen expression in vitro using ARPE-19 cells, and we analyzed extracellular matrix marker expression in PVR membrane and internal limiting membrane patient samples. We performed a prospective noninterventional cohort study, recruiting 125 patients undergoing vitrectomy for RRD and macular hole surgery, measured vitreous levels of TGF-β2 and decorin by ELISA, and followed them up for 6 months. Patients who did not develop PVR were compared to those who did, in order to determine whether vitreous TGF-β2 and decorin levels predicted PVR development. In vitro, TGF-β2 induced EMT and collagen production. Decorin strongly inhibited EMT and collagen production at high levels. PVR membranes expressed high levels of fibrosis-associated proteins, consistent with EMT. Vitreous TGF-β2 levels were unchanged between patients with macular holes and RRD who did or did not subsequently develop PVR. Average decorin levels were higher in the vitreous of RRD patients who subsequently developed PVR compared to those who did not, but at the measured vitreous concentrations (1-2 μg/mL), decorin did not demonstrate an in vitro inhibitory effect on EMT. In vitro, high concentrations of decorin inhibited EMT and fibrosis. At the levels seen in human vitreous, decorin did not prevent fibrosis or EMT in vitro, and higher initial vitreous decorin levels were associated with the development of postoperative PVR after vitrectomy to treat RRD, but did not reliably predict the outcome.

Preliminary results of the placental decorin profile in bovine pregnancy and parturition

Decorin is a small leucine-rich proteoglycan which is involved in multiple biological functions mainly as a structural and signaling molecule. Due to its biological properties in connective tissue, decorin may participate in remodeling of ECM during attachment and detachment of placenta within the course of pregnancy and at parturition in cows. The aim of the study was to detect the presence of decorin protein in bovine placental tissues and to evaluate its profile during pregnancy and at parturition. Placental tissues from healthy pregnant cows (2–5 month) were collected in abattoir (n = 10), while parturient tissues were obtained during caesarian section at physiological term (n = 6). Maternal and fetal parts were separated manually and subjected to homogenization and to quantitative ELISA and verification by Western blotting with anti-decorin antibodies. ELISA test showed that the concentration of decorin during pregnancy was higher in the fetal part of placenta compared with the maternal part (p < 0.001). Similar pattern was noted regarding to maternal and fetal samples derived from parturient cows. Our preliminary results demonstrate that the concentration of decorin is gestation time-dependent in healthy bovine placenta. Possible confirmation of the involvement of decorin in early pregnancy attachment and detachment of the placenta during parturition requires further research.

Clinical utility of decorin in follicular fluid as a biomarker of oocyte potential

This study investigated the concentration of decorin (DCN) in mature follicular fluid and the existence in the granulosa cells. It also investigated whether DCN is useful as a biomarker for outcomes of assisted reproductive technology (ART). A retrospective cohort study was performed involving 130 oocytes of 88 patients treated with ART because of unexplained infertility. The concentration of DCN in the follicular fluid (F-DCN) was 39.26ng/ml (median value); it was higher than that in serum. F-DCN of the oocytes fertilized by intracytoplasmic sperm injection (ICSI) was significantly lower than that of oocytes that were not fertilized (33.24ng/ml vs 40.18ng/ml; P=0.043). When a cut-off level of 34.5ng/ml was set according to the receiver-operating characteristic curve, the fertilization rate of the oocytes from the follicles in which F-DCN was lower than the cut-off level tended to be good compared to that of the oocytes with F-DCN higher than the cut-off level (P=0.052). DCN is less likely to be produced by the granulosa cells (GCs), because it was not detected in GCs by immunostaining and Western blot analysis. F-DCN has a possibility to be a biomarker indicating the quality of oocytes collected from the corresponding follicle.

Decorin, a growth hormone-regulated protein in humans.

Growth hormone (GH) stimulates connective tissue and muscle growth, an effect that is potentiated by testosterone. Decorin, a myokine and a connective tissue protein, stimulates connective tissue accretion and muscle hypertrophy. Whether GH and testosterone regulate decorin in humans is not known. To determine whether decorin is stimulated by GH and testosterone. Randomized, placebo-controlled, double-blind study. 96 recreationally trained athletes (63 men, 33 women) received 8 weeks of treatment followed by a 6-week washout period. Men received placebo, GH (2 mg/day), testosterone (250 mg/week) or combination. Women received either placebo or GH (2 mg/day). Serum decorin concentration. GH treatment significantly increased mean serum decorin concentration by 12.7 ± 4.2%; P < 0.01. There was a gender difference in the decorin response to GH, with greater increase in men than in women (∆ 16.5 ± 5.3%; P < 0.05 compared to ∆ 9.4 ± 6.5%; P = 0.16). Testosterone did not significantly change serum decorin. Combined GH and testosterone treatment increased mean decorin concentration by 19.5 ± 3.7% (P < 0.05), a change not significantly different from GH alone. GH significantly increases circulating decorin, an effect greater in men than in women. Decorin is not affected by testosterone. We conclude that GH positively regulates decorin in humans in a gender-dimorphic manner.

Decorin over-expression by decidual cells in preeclampsia: a potential blood biomarker

Decorin, a leucine-rich proteoglycan that is produced by decidual cells, limits invasion and endovascular differentiation of extravillous trophoblast cells during early placentation by binding to multiple tyrosine kinase receptors, in particular, vascular endothelial growth factor receptor-2. Because many studies have reported an association between poor trophoblast invasion and endovascular differentiation with preeclampsia, the studies reported here tested (1) whether decorin over-expression in the chorionic villi and/or basal decidua is associated with preeclampsia and, if so, (2) whether this association results in a hypoinvasive placenta, and (3) whether elevated plasma decorin concentration in the second trimester is a predictive biomarker for preeclampsia. Decorin messenger RNA expression was measured with quantitative polymerase chain reaction at the tissue level and with in situ hybridization at the cellular level using (35)S-labeled antisense complimentary RNA probe in placentas from healthy control subjects and subjects with preeclampsia (14 each, 23-40 weeks of gestation). Tissue sections of the same placentas were also immunostained for decorin protein. A decorin over-expressing human endometrial stromal cell line was tested for invasion-regulatory effects on an invasive first-trimester extravillous trophoblast cell line HTR-8/SVneo plated in cocultures that were separated by a semipermeable membrane. Furthermore, we conducted retrospective measurements of plasma decorin levels during the second trimester (15-18 weeks of gestation) in a cohort of 28 body mass index-matched pairs of control subjects and subjects with preeclampsia before the onset of clinical disease. First, decorin messenger RNA expression at the cellular level measured with in situ hybridization exhibited profoundly higher expression levels in basal plate decidual cells within the placentas from preeclamptic subjects than those from control subjects at all gestational ages, whereas no difference between the 2 subject groups was noted in villus mesenchymal cells. Similarly decorin messenger RNA expression at the tissue level in chorionic villi (primarily resulting from fetally derived mesenchymal cells) did not differ significantly between control and preeclampsia placentas. These findings were validated with immunostaining for decorin protein. Second, knocking down decorin gene in a decorin over-expressing endometrial cell line (used as an invitro surrogate of decorin over-expressing decidual cells) in cocultures with extravillous trophoblast cells abrogated its invasion-restraining actions on trophoblast cells, which indicated paracrine contribution of decorin over-expressing decidua to the poor trophoblast invasiveness in situ. Finally, retrospective measurement of plasma decorin levels during the second trimester in 28 body mass index-matched pairs of control subjects and subjects with preeclampsia revealed elevated plasma decorin levels in all subjects with preeclampsia in all body mass index groups. A receiver operating characteristic curve analysis revealed strong diagnostic performance of plasma decorin in the prediction of preeclampsia status. Although there was no significant gestational age-related change in decorin levels during the second trimester in control or subjects with preeclampsia, we found that plasma decorin had a significant inverse relationship with body mass index or bodyweight. We conclude that decorin over-expression by basal decidual cells is associated with hypoinvasive phenotype and poor endovascular differentiation of trophoblast cells in preeclampsia and that elevated plasma decorin concentration is a potential predictive biomarker for preeclampsia before the onset of clinical signs.

Chorioamniontis in preterm delivery is associated with degradation of decorin and biglycan and depletion of hyaluronan in fetal membranes

ObjectiveThe proteoglycan decorin stabilizes collagen whereas biglycan and hyaluronan disrupt well-organized collagen. The aim was to determine the concentrations of these constituents in fetal membranes in relation to gestational age, preterm labour, PPROM and chorioamnionitis. Study designPreterm fetal membranes (24–34 weeks gestation) were obtained from elective caesarean deliveries (N = 4), from PPROM (N = 14), and from preterm labour (N = 14). Term fetal membranes from elective caesarean deliveries (N = 9) and spontaneous vaginal deliveries (N = 11) were used for comparison. Chorioamnionitis was assessed histologically. The proteoglycans were analysed using alcian blue precipitation, SDS-PAGE and immunostaining. Hyaluronan was estimated by a radioimmunoassay. ResultsPreterm amniotic membranes with chorioamnionitis displayed a 8-fold decrease in hyaluronan concentration as well as a pronounced (88%) degradation of decorin and biglycan (p < 0.05).The amnion from preterm elective caesarean sections had higher decorin (3.2 vs. 1.7 μg/mg, p < 0.05) and lower biglycan (0.4 vs. 1.0 μg/mg, p < 0.05) concentrations as compared to similar term amnion (p < 0.05), whereas the hyaluronan concentrations were not associated with gestational age. Also the chorio-decidua from preterm caesarean sections had higher decorin concentrations (1.8 vs. 1.0 μg/mg, p < 0.05) whereas the biglycan concentration was unchanged. Labour (term as well as preterm) was characterized by increased hyaluronan and biglycan concentrations in the amnion (not statistically significant). ConclusionThe biglycan/decorin balance increases during third trimester of pregnancy and during active labour. This relation might contribute to mechanical weakening of the membranes. Chorioamnionitis induces dramatic degradation of both proteoglycans and hyaluronan, which can explain the decreased biomechanical strength.

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.

Decorin is down‐regulated in multiple myeloma and MGUS bone marrow plasma and inhibits HGF‐induced myeloma plasma cell viability and migration

Decorin is a stromal-produced small leucine-rich proteoglycan known to attenuate tumour pro-survival, migration, proliferation and angiogenic signalling pathways. Recent studies have shown that decorin interacts with the hepatocyte growth factor (HGF) receptor c-Met, a potential key pathway in multiple myeloma (MM). Decorin levels in paired peripheral blood and bone marrow plasma samples from healthy volunteers (HV) (n=23), and patients with monoclonal gammopathy of undetermined significance (MGUS) (n=41) and MM (n=19) were determined by ELISA. Further, the ability of decorin to inhibit HGF-induced effects on MM cell lines were analysed in vitro using cell viability and Transwell migration assays. We found that decorin concentrations were significantly higher (P<0.05) in bone marrow (BM) plasma from HVs (median 35.2ng/mL; range, 15.3-99.1) compared with MGUS (median 22.5ng/mL; range, 11.1-59.5) and patients with MM (median 21.5ng/mL; range, 10.6-35.9). Decorin levels were higher in BM plasma than in peripheral blood in all groups, with a BM/PB ratio of 3.9, 3.4 and 2.5 for HV, MGUS and MM, respectively. A positive correlation (Spearman's ρ=0.51, P<0.05) was found between simultaneously measured levels of HGF and decorin in BM plasma in HVs, but not in MGUS or MM samples. Functionally, decorin inhibited HGF-induced migration and viability of INA-6 and ANBL-6 MM cell lines, independent of c-Met down-regulation. Our results show that decorin is down-regulated in MGUS and MM bone marrow plasma and that it inhibits HGF-induced viability and migration of myeloma cell lines in vitro.