人前列腺癌组织雌激素受体α、β亚单位基因mRNA的表达

目的　了解雌激素受体α(ERα)、β(ERβ)mRNA在人前列腺癌 (PCa)组织中的表达状况。方法　采用半定量逆转录 聚合酶链反应 (RT PCR)技术检测 32例PCa、32例良性前列腺增生患者、12例正常前列腺组织者中ERα、ERβmRNA的表达并进行基因测序。 结果　与良性前列腺增生组织相比 ,PCa组织ERαmRNA表达明显增强 ,而ERβmRNA表达明显减弱 (均P <0 0 1)。中晚期、低分化PCa组织ERαmRNA表达明显高于早期、中高分化PCa,而ERβmRNA则相反 (均P <0 0 1)。激素抵抗型PCaERαmRNA表达增强 ,而ERβmRNA表达明显降低 (均P <0 0 5 )。 结论　ERα、ERβ在PCa组织中的不同表达状况可能与PCa组织病理生物学特性有关。对ER特别是ERβ的研究 ,有助于对PCa特别是激素抵抗型PCa的生物学特性判断和治疗。     

Semiquantitative reverse transcription-polymerase chain reaction analysis of syndecan-1 and -4 messages in cartilage and cultured chondrocytes from osteoarthritic joints

OBJECTIVE: To determine the steady-state of messenger RNA (mRNA) levels of syndecan-1 and syndecan-4 in cartilage samples and chondrocytes derived from human osteoarthritic knee joints. METHODS: Steady-state levels of gene-specific mRNA (relative to beta-actin) were measured by semiquantitative polymerase chain reaction (PCR). RESULTS: RT-PCR allowed detection of syndecan-1 (for the first time) and syndecan-4 in both cartilage samples and articular chondrocytes cultured as primary monolayers. The mRNA levels of syndecan-1 were reduced in cartilage tissue from heavily damaged compared to normal-looking areas whereas those of syndecan-4 were significantly increased. In contrast, the expression of syndecan-1 was higher in cultured chondrocytes derived from the fibrillated osteoarthritic cartilage than in cells obtained from intact cartilage, while the syndecan-4 message levels did not differ between the two sites. CONCLUSION: The expression of the cell-surface syndecans 1 and 4 is altered during the osteoarthritic degradative process of the knee joint. The discoordinate syndecan gene expression, which is probably related to the chondrocyte proliferation and clustering, may contribute to the disorganization of the cartilage and the development of OA processes. Isolation and culturing the chondrocytes as monolayers dramatically change the expression of these genes and cannot reflect the in situ condition.     

Expression analysis of different collagens and cytokines in cartilage cells derived from arthrotic hip and knee joints

AIM: Osteoarthritis (OA) is characterized by an irreversible destruction of articular cartilage. This is associated with a multiplicity of factors, causing an increased catabolic metabolism in cartilage. However, the prevalence of the OA is very variable in different joints. Therefore , we conducted a comparative analysis of chondrocytes derived from knee and hip joints with respect to their expression of inflammatory factors, such as IL-1beta, IL-1beta-receptorantagonist, iNOS, components of cartilage matrix (collagen I, II, and VI) as well as vimentin. METHODS: Different cytokines and proteins were detected by immune-histochemical staining of cartilage samples ex vivo. Further, chondrocytes were isolated from OA knee and hip joints, expanded in vitro and gene expression patterns were investigated by quantitative RT-PCR. RESULTS: Chondrocytes from knee and hip joints of OA patients express collagenes I, II and VI, IL-1beta and IL-1beta-RA, iNOS as well as Vimentin. A significant difference in gene expression patterns was not found in chondrocytes from the hip joints versus the knee joint ex vivo or in primary culture cells in vitro. However, in vitro the expression of type I collagen exceeded the expression of type II collagen. The IL-1beta-expression was high ex vivo, remained low during primary culture but was significantly elevated after primary culture in hip chondrocytes. CONCLUSION: Osteoarthritic gene expression patterns in cells derived from hip or knee joints ex vivo and in primary culture were not significantly different. We conclude that the rather frequent occurrence of OA in these joints in comparison to the ankle joint may be associated with a close physiological relation of cells in these joints. However, future studies which will include ankle cartilage must be investigated in further detail.     

Altered electrophysiological responses to mechanical stimulation and abnormal signalling through alpha5beta1 integrin in chondrocytes from osteoarthritic cartilage

OBJECTIVE: To establish whether chondrocytes from normal and osteoarthritic human articular cartilage recognize and respond to pressure induced mechanical strain in a similar manner.DESIGN: Chondrocytes, extracted from macroscopically normal and osteoarthritic human articular cartilage obtained from knee joints at autopsy, were grown in monolayer culture and subjected to cyclical pressure-induced strain (PIS) in the absence or presence of anti-integrin antibodies, agents known to block ion channels and inhibitors of key molecules involved in the integrin-associated signalling pathways. The response of the cells to mechanical stimulation was assessed by measuring changes in membrane potential. RESULTS: Unlike chondrocytes from normal articular cartilage, which showed a membrane hyperpolarization response to PIS, chondrocytes from osteoarthritic cartilage responded by membrane depolarization. The mechanotransduction pathway involves alpha5beta1 integrins, stretch-activated ion channels, tyrosine kinases and phospholipase C but the actin cytoskeleton and protein kinase C, which are important in the membrane hyperpolarization response in normal chondrocytes, are not necessary for membrane depolarization in osteoarthritic chondrocytes in response to PIS. CONCLUSION: Chondrocytes derived from osteoarthritic cartilage show a different signalling pathway via alpha5beta1 integrin in response to mechanical stimulation which may be of importance in the production of phenotypic changes recognized to be present in diseased cartilage.     

Expression of NG2/human melanoma proteoglycan in human adult articular chondrocytes

OBJECTIVE: NG2 is a transmembrane chondroitin sulfate (CS) rich proteoglycan originally identified in rats. It has recently been shown to be identical to human melanoma proteoglycan (HMPG). In rats NG2 has a limited distribution in adult tissues, being expressed predominantly by neuronal and glial cells whereas during development it is also expressed in developing mesenchyme including cartilage. NG2/HMPG has putative roles in interactions between glial and melanoma cells with extracellular matrix (ECM) molecules. This study was undertaken to assess whether NG2/HMPG was expressed by normal and osteoarthritic human articular chondrocytes. DESIGN: Cryostat sections of human fetal knee joints and normal and osteoarthritic articular cartilage were immunostained with antibodies against rat NG2 (N143.8) and HMPG (M28B5, 9.2.27). Immunoprecipitation and Western blotting was carried out on protein extracts of chondrocytes from normal and osteoarthritic cartilage. Immunofluorescence of NG2 and potential ligands was carried out in vitro on cells from normal and osteoarthritic cartilage. RESULTS: Fetal and both normal and osteoarthritic adult cartilage showed strong immunoreactivity for NG2/HMPG. Western blotting showed a smeared component of molecular weight greater than 400 kDa and a faint band at 250 kDa which became predominant upon digestion with chondroitinase ABC. Immunofluorescence of chondrocytes in vitro showed NG2 to be distributed in a punctate pattern without co-localization of actin or several ECM proteins including fibronectin and type VI collagen. CONCLUSION: NG2/HMPG is expressed by human fetal and adult chondrocytes and in adult articular chondrocytes the core protein is chondroitin sulfated. The function of this molecular in human articular cartilage remains to be defined.     

The composition of normal and osteoarthritic articular cartilage from human knee joints. With special reference to unicompartmental replacement and osteotomy of the knee

The articular cartilage from nineteen osteoarthritic and fourteen normal control adult human knee joints was analyzed for changes in water content, proteoglycan composition and structure, glycosaminoglycan synthesis rates, and cell content. We found no significant differences between visually intact cartilage from osteoarthritic knee joints and cartilage from control joints for any of the parameters studied. In osteoarthritic specimens in which the cartilage surface was not intact the biochemical changes depended on the degree of fibrillation. Surface-fibrillated specimens had a higher water content in the surface layers but no change in the content or synthesis rate of glycosaminoglycan. Deeply fibrillated cartilage, however, had an increased water content through its full depth, and there was a decrease in both the rate of synthesis and the content of glycosaminoglycans. Clinical Relevance: The results of this study suggest that degenerative changes in osteoarthritic knees are focal in origin and that corrective osteotomy or unicompartmental joint replacement might be rational procedures for knees in which the cartilage in all of one compartment is visually intact.     

Activation of annexin II and V expression, terminal differentiation, mineralization and apoptosis in human osteoarthritic cartilage

OBJECTIVE: To test the hypothesis that terminal differentiation of chondrocytes in human osteoarthritic cartilage might lead to the failure of repair mechanisms and might cause progressive loss of structure and function of articular cartilage. DESIGN: Markers for terminally differentiated chondrocytes, such as alkaline phosphatase, annexin II, annexin V and type X collagen, were detected by immunohistochemical analysis of human normal and osteoarthritic knee cartilage from medial and lateral femoral condyles. Apoptosis in these specimens was detected using the TUNEL labeling. Mineralization and matrix vesicles were detected by alizarin red S staining and electron microscopic analysis. RESULTS: Alkaline phosphatase, annexin II, annexin V and type X collagen were expressed by chondrocytes in the upper zone of early stage and late stage human osteoarthritic cartilage. However, these proteins, which are typically expressed in hypertrophic and calcifying growth plate cartilage, were not detectable in the upper, middle and deep zones of healthy human articular cartilage. TUNEL labeling of normal and osteoarthritic human cartilage sections provided evidence that chondrocytes in the upper zone of late stage osteoarthritic cartilage undergo apoptotic changes. In addition, mineral deposits were detected in the upper zone of late stage osteoarthritic cartilage. Needle-like mineral crystals were often associated with matrix vesicles in these areas, as seen in calcifying growth plate cartilage. CONCLUSION: Human osteoarthritic chondrocytes adjacent to the joint space undergo terminal differentiation, release alkaline phosphatase-, annexin II- and annexin V-containing matrix vesicles, which initiate mineral formation, and eventually die by apoptosis. Thus, these cells resume phenotypic changes similar to terminal differentiation of chondrocytes in growth plate cartilage culminating in the destruction of articular cartilage in osteoarthritis.     

Estrogen receptor beta/alpha ratio predicts response of pancreatic cancer cells to estrogens and phytoestrogens

BACKGROUND: Reports on hormone receptor expression of pancreatic cancer (PaCa) cells and treatment responses to antihormonal therapy are conflicting. We examined estrogen receptor (ER) expression in PaCa cells and investigated its function in estrogen-mediated cell proliferation. METHODS: Protein levels of ERalpha and ERbeta in 8 human PaCa lines were detected by Western blot analysis. Cell proliferation was measured by sulforhodamine B analysis. ER modulators included diethylstilbestrol (DES), estradiol (E2), 4-hydroxytamoxifen (Tam), genistein (Gen), and Coumestrol (Coum). RESULTS: ERalpha levels were detected in all eight, and ERbeta in seven cell lines. ERbeta/ERalpha ratio ranged from 0.4 to 111 (median: 6.4, >5 in seven lines). Median maximal growth stimulation (in %, observed at 20 to 200 nM) was 19 (DES), 39 (E2), 20 (Tam), 22 (Gen), and -9 (Coum); median maximal inhibition (at 40 to 60 microM) was 59 (DES), 36 (E2), 25 (Tam), 43 (Gen), and 50 (Coum). The extent of E2 and Gen stimulatory effects correlated with the ERbeta/ERalpha ratio (Kendall's tau: 0.714, P = 0.024), but not ERalpha or ERbeta levels alone. Only Coum-induced inhibition correlated with the ERbeta/ERalpha ratio (P = 0.006) and with ERalpha expression (r = 0.753, P = 0.03). Gemcitabine-induced PaCa cytotoxicity (at IC(40)) was significantly reduced by E2, Gen, and Coum. CONCLUSIONS: PaCa proliferation in vitro is highly estrogen sensitive, and in contrast to other reports, ERs are frequently expressed. In 7/8 cell lines, ERbeta expression outweighs ERalpha expression. The impact of the ERbeta/ERalpha ratio on estrogen-mediated growth stimulation and reduced cytotoxicity at physiological concentrations may have clinical implications on PaCa therapy.     

Novel cartilage-specific splice variants of fibronectin

OBJECTIVE: To determine the nature of alternatively spliced isoforms of fibronectin expressed in healthy bovine articular cartilage and cartilage derived from human osteoporotic and osteoarthritic joints. DESIGN: Our study focused on a single alternatively spliced region of the fibronectin gene, the variable region. Bovine cartilage samples were obtained within 12h of slaughter and human cartilage samples were obtained within 8h of the time of joint replacement surgery. RNA was extracted and alternatively spliced isoforms of fibronectin were amplified using RT-PCR. RESULTS: Two novel alternatively spliced forms of fibronectin designated (V+I-10)(-) and (V+III-15)(-) were identified in bovine articular cartilage. Fibronectin is composed of multiple repeats of three types of homologous units and these two novel isoforms specifically splice out single individual repeating units. Expression of all these isoforms was dependent upon the presence of an extracellular matrix. In the human samples the expression profiles obtained with osteoporotic hip and osteoarthritic knee cartilage was not uniform. The (V+C)(-) isoform was present in all samples and the (V+I-10)(-) isoform was distributed between both osteoporotic and osteoarthritic cartilage. However, the (V+III-15)(-) isoform was shown to be associated with osteoarthritic cartilage with statistical significance (P< 0.015 ). In addition a third novel splice variant was identified and designated as III-15X. Translation of the III-15X isoform results in a truncated form of fibronectin lacking a significant portion of the C-terminus. Further RT-PCR analysis of several other tissue types suggests that these variants are cartilage specific. CONCLUSION: Our results demonstrate the existence of three new cartilage specific isoforms of fibronectin and indicate that expression of one or more may be associated with osteoarthritis.Copyright 2002 OsteoArthritis Research Society International. Published by Elsevier Science Ltd. All rights reserved.     

Cartilage-derived morphogenetic protein-1 and -2 are endogenously expressed in healthy and osteoarthritic human articular chondrocytes and stimulate matrix synthesis

OBJECTIVE: We investigated whether chondrocytes derived from osteoarthritic cartilage may lose their responsiveness to cartilage-derived morphogenetic protein-1, -2 (CDMP-1, -2) and osteogenic protein-1 (OP-1) compared with healthy cells, thus leading to an impaired maintenance of matrix integrity. DESIGN: Chondrocytes were isolated from articular cartilage from patients with and without osteoarthritic lesions. Cells were grown as monolayer cultures for 7 days in a chemically defined serum-free basal medium (BM) in the presence of recombinant CDMP-1, -2, and OP-1. Glycosaminoglycan synthesis was measured by [35S]Sulfate incorporation into newly synthesized macromolecules. Cell proliferation was investigated by [3H]Thymidine incorporation. The endogenous gene expression of CDMPs/OP-1 and their respective type I and type II receptors was examined using RT-PCR. The presence of CDMP proteins in tissue and cultured cells was detected by Western immunoblots. RESULTS: mRNAs coding for CDMPs and their respective receptors are endogenously expressed not only in healthy, but also in osteoarthritic cartilage. CDMP proteins are present in both normal and osteoarthritic articular cartilage and cultured chondrocytes. CDMP-1, CDMP-2 and OP-1 markedly increased glycosaminoglycan synthesis in both healthy (P< 0.01) and osteoarthritic (P< 0.05) human articular chondrocytes. A comparison of the glycosaminoglycan biosynthetic activity between healthy and osteoarthritic samples revealed no detectable difference, neither in stimulated nor in unstimulated cultures. [(3)H]Thymidine incorporation showed that CDMPs/OP-1 did not affect cell proliferation in vitro. CONCLUSION: CDMPs and OP-1 exert their anabolic effects on both healthy and osteoarthritic chondrocytes indicating no loss in responsiveness to these growth factors in OA. The endogenous expression of CDMPs/OP-1 and their receptors suggest an important role in cartilage homeostasis.     

The fate of chondrocyte in osteoarthritic cartilage of transgenic mice expressing bovine GH

OBJECTIVE: The aim of the present study was to demonstrate whether bGH transgenic mice develop OA. We therefore studied in this animal model the structural features of cartilage and the subchondral bone changes of the knee joints that may be associated with osteoarthritic lesion. METHOD: Degenerative changes in the knee joints of bGH transgenic female mice (N = 11) and control mice (N = 11) were histologically analyzed at the age of 7 months. Histochemical and stereological studies were conducted. Immunohistochemistry on cell cyclin activity (assessed by anti-PCNA labeling) and cell viability (assessed by bcl-2 expression), as well as ribosomal activity (AgNOR), TNF-alpha expression and apoptosis (TUNEL technique) were performed. In ten 7-month-old female mice (Tg+ N = 5; control N = 5) the knee articular cartilages were studied with electron microscopy techniques. RESULTS: Disruption of the articular surface (18.2%), cleft (63.7%), cloning (81.8%), hypocellularity of chondrocytes (18.2%), moderate (54.6%) to severe (45.4%) loss of safranin-O staining, and duplication and rupture of the tidemark (54.5%) were some of the main features observed in articular cartilage chondrocytes of bGH transgenic mice. Furthermore, cell cyclin activity and cell viability decreased, while TNF-alpha expression and TUNEL+ cells increased. These chondrocytes also showed an increase in the number of black dots per cell, as revealed by the AgNOR technique. CONCLUSION: Our results show that bGH transgenic mice develop a lesion of the articular cartilage consistent with that described in osteoarthritis.     

Increased expression and activation of cathepsin K in human osteoarthritic cartilage and synovial tissues

Few studies have analyzed Cathepsin K (CatK) expression in human osteoarthritic tissues. We investigated CatK expression and activation in human articular cartilage using clinical specimens. Human osteoarthritic cartilage was obtained during surgery of total hip arthroplasty (n = 10), and control cartilage was from that of femoral head replacement for femoral neck fracture (n = 10). CatB, CatK, CatL, CatS, and Cystatin C (CysC) expressions were evaluated immunohistochemically and by real‐time PCR. Intracellular CatK protein was quantified by ELISA. Intracellular CatK activity was also investigated. Osteoarthritis (OA) chondrocytes were strongly stained with CatK, particularly in the superficial layer and more damaged areas. CatB, CatL, CatS, and CysC were weakly stained. CatK mRNA expression was significantly higher in OA group compared to that in control group (p = 0.043), whereas those of CatB, CatL, CatS, and CysC did not differ significantly. Mean CatK concentration (4.83 pmol/g protein) in OA chondrocytes was higher than that (3.91 pmol/g protein) in control chondrocytes (p = 0.001). CatK was enzymatically more activated in OA chondrocytes as compared with control chondrocytes. This study, for the first time, revealed increased CatK expression and activation in human OA cartilage, suggesting possible crucial roles for it in the pathogenesis of osteoarthritic change in articular cartilage. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:127–134, 2016.     

Presence of pannus-like tissue on osteoarthritic cartilage and its histological character

OBJECTIVE: To investigate and characterize pannus-like tissue which is often present on osteoarthritic articular cartilage. DESIGN: Cartilage specimens from 15 knee and five hip joints of patients with osteoarthritis (OA) undergoing arthroplasty were stained for HE and Safranin-O. They were also immunostained by antitype I collagen, type II collagen, CD68, IL-1beta and MMP3 antibodies. RESULTS: Ninety percent of joints have pannus-like tissue on the articular surface, preferentially in a marginal area. The articular cartilage was divided into three regions according to the location: the marginal zone, the intermediate zone and the paraeburnated zone. Pannuslike tissue in OA knee joint occurred 45.9%, 27.5% and 11.1% of the surface of each region respectively. Histologically, pannus-like tissue could be classified into the vascular type and the fibrous type. Extracellular matrix of both types of tissues were negative for Safranin-O and type II collagen, but positive for type I collagen. IL-1beta and MMP3 expressing cells are predominant in pannus-like tissue, whereas CD68 positive cells were infiltrated in only a few samples. Vascular type tissue kept continuity with bone marrow suggesting mesenchymal origin. CONCLUSION: Pannus-like tissue exists in advanced OA cartilage, preferentially in the marginal zone. It expressed IL-1beta and MMP3, which strongly suggests that it contributes to cartilage degradation.     

Chondrocyte cultures from human proximal interphalangeal finger joints

Osteoarthritis (OA) of the hand is a common disease resulting in pain and impaired function. The pathogenesis of hand OA (HOA) is elusive and models to study it have not been described. Chondrocyte culture has been essential to understand cartilage degeneration, which is a hallmark of OA. We investigated the feasibility of human chondrocyte culture derived from proximal interphalangeal (PIP) finger joints. Hyaline cartilage of the PIP and knee joints was obtained from human cadavers. Chondrocytes harvested up to 236 h after death of the donors were viable and expressed chondrocyte‐specific genes. Gene expression comparing chondrocytes from PIP and knee joints using Affymetrix GeneChip arrays resulted in a unique PIP‐specific gene expression pattern. Genes involved in developmental processes including the WNT pathway were differentially expressed between the joints. These findings suggest that our knowledge on chondrocyte biology derived mainly from knee and hip joints may not apply to chondrocytes of the PIP joints and some of the distinctive features of HOA may be caused by the specific properties of PIP chondrocytes. Chondrocyte culture of PIP cartilage is a novel tool to study cartilage degeneration in HOA. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1569–1575, 2016.     

Abnormal occurrence of a large chondroitin sulfate proteoglycan, PG-M/versican in osteoarthritic cartilage

The expression of PG-M in osteoarthritic cartilage was investigated. Cartilage from five hip joints with osteoarthritis (OA) and control cartilage from five knee joints with post-traumatic injury were obtained and analyzed with anti-PG-M antibodies. Control cartilage showed no staining, but in osteoarthritic cartilage there was strong staining of the cytoplasm of chondrocytes with abnormal morphology. The cytoplasm of inflammatory cells invading the osteoarthritic cartilage matrix was also strongly stained which led to determining the sequence of PG-M core protein. The deduced amino acid sequence and homology analysis indicated that PG-M had a complement regulatory protein-like domain, a lectin-like domain, two EGF-like domains from the carboxyl-terminal with an extremely high homology to the respective domains of versican, a large proteoglycan expressed by human fibroblasts. The anti-PG-M antibodies cross-reacted with Ver-27b fusion protein which was expressed by a cDNA clone coding the N-terminal portion of versican core protein. Thus, the immunological and sequencing data suggest that PG-M is a molecule similar to or identical with human versican, and that the material in cartilage reactive to the anti-PG-M antibodies is versican. These findings suggest the PG-M/versican is expressed in osteoarthritic cartilage.