Upregulated miR-125b mitigates inflammation, astrocyte activation, and dysfunction of spinal cord injury by inactivating the MAPK pathway.

BACKGROUND: Since the abnormal expression of miR-125b in spinal cord injury (SCI) and the regulatory effect of miR-125b on the MAPK pathway have been expounded, we attempt to investigate whether miR-125b exerts a regulatory effect on SCI by modulating the MAPK pathway. METHOD: A SCI rat model was established. The rats were treated with miR-125b antagomir or agomir, and their motor function affected by miR-125b was further detected by Basso-Beattie-Bresnahan (BBB) scoring. The histopathological changes and neuronal loss in the spinal cord were evaluated using hematoxylin-eosin and Nissl staining. Microglia-conditioned medium (MCM) was prepared and further used to treat the astrocytes, the activation of which was evaluated via immunofluorescence staining. The expressions of miR-125b, inflammation-related factors (IL-6, IL-1ß, TNF-α, and IL-10), and MAPK pathway-related proteins (p38, ERK1/2, and JNK1/2 as well as their phosphorylated (p) forms) in the spinal cord, serum, and MCM-treated astrocytes of rats were determined by reverse-transcription quantitative polymerase chain reaction (RT-qPCR), enzyme-linked immunosorbent assay, and Western blot. RESULT: MiR-125b was lowly expressed in SCI-modeled rats. MiR-125b downregulation aggravated the impaired motor function, the disorder within the tissue, astrocyte activation, and neuron loss in the spinal cord tissues of SCI-modeled rats, while miR-125b upregulation did oppositely. MiR-125b downregulation enhanced the levels of IL-6, IL-1ß, TNF-α, p38, p-p38, p-ERK1/2, and p-JNK1/2, whilst reducing that of IL-10. Contrarily, miR-125b upregulation exerted the opposite effects in SCI-modeled rats and MCM-treated astrocytes. CONCLUSION: Up-regulation of miR-125b mitigates inflammation, astrocyte activation, and dysfunction in SCI by inactivating the MAPK pathway.

Human Peripheral Nerve-Derived Pluripotent Cells Can Be Stimulated by In Vitro Bone Morphogenetic Protein-2.

We have recently identified a population of cells within the peripheral nerves of adult rodent animals (mice and rats) that can respond to Bone Morphogenetic Protein-2 (BMP-2) exposure or physical injury to rapidly proliferate. More importantly, these cells exhibited embryonic differentiation potentials that could be induced into osteoblastic and endothelial cells in vitro. The current study examined human nerve specimens to compare and characterize the cells after BMP-2 stimulation. Fresh pieces of human nerve tissue were minced and treated with either BMP-2 (750 ng/mL) or a PBS vehicle for 12 h at 37 °C, before being digested in 0.2% collagenase and 0.05% trypsin-EDTA. Isolated cells were cultured in a restrictive stem cell medium. Significantly more cells were obtained from the nerve pieces with the BMP-2 treatment in comparison with the PBS vehicle controls. Cell colonies started to form at Day 3. Expressions of the four transcription factors, namely, Klf4, c-Myc, Sox2, and Oct4, were confirmed at both the transcriptional and translational levels. The cells can be maintained in the stem cell culture medium for at least 6 weeks without changing their morphology. When the cells were transferred to a fibroblast growth medium, dispersed spindle-shaped motile cells were noted and became fibroblast activated protein-α (FAP) positive with immunocytochemistry staining. The data suggest that human peripheral nerve tissue also contains a population of cells that can respond to BMP-2 and express Klf4, Sox2, cMyc, and Oct4-the four transcription factors driving cell pluripotency. These cells are able to differentiate into FAP-positive fibroblasts. In summary, in human peripheral nerves also reside a population of quiescent cells with pluripotency potential that may be the same cells as rodent nerve-derived adult stem (NEDAPS) cells. It is proposed that these cells are possibly at the core of a previously unknown natural mechanism for healing an injury.

Inconsistency of Bone Mineral Density Between Femoral Head and Proximal Femur After Femoral Neck Fracture Surgery Indicates Great Possibility of Femoral Head Necrosis.

On clinical observation, it was found that the bone mineral density (BMD) of the femoral head and proximal femur was not consistent in some patients with femoral neck fracture after surgery. The current study was performed to explore whether this phenomenon was associated with femoral head necrosis after surgery for femoral neck fracture. Bone mineral density inconsistency is when the difference of the sum of pixel values on both sides of the fracture line has exceeded 30%. Statistical analysis was performed on the clinical characteristics of 271 patients who had received the operation for femoral neck fracture. Chi-square test, Spearman rank correlation, independent sample t test, Kaplan-Meier method, and log-rank test, as well as univariate Cox regression and multivariate Cox regression, were used to analyze the potential relationship among related factors. It was revealed that the incidence of inconsistency in BMD between the femoral head and proximal femur was significantly increased in patients with femoral head necrosis after surgery for femoral neck fracture, and that the consistency was considerably high between BMD inconsistency and femoral head necrosis. The inconsistent BMD occurred 11.1 months earlier than the necrosis of the femoral head. Cox multivariate regression analysis indicated that the inconsistency in BMD between the femoral head and proximal femur after surgery for femoral neck fracture was an independent prognostic factor affecting femoral head necrosis. The inconsistent changes in BMD between the femoral head and proximal femur after surgery for femoral neck fracture indicate a great possibility of femoral head necrosis. [Orthopedics. 2021;44(2):e223-e228.].

Ginkgolide B improves multiterritory perforator flap survival by inhibiting endoplasmic reticulum stress and oxidative stress.

BACKGROUND: The therapeutics used to promote perforator flap survival function induces vascular regeneration and inhibit apoptosis. The present study aimed to explore the potential mechanism of the angiogenesis effects of Ginkgolide B (GB) in perforator flaps. Methods: A total of 72 rats were divided into three groups and treated with saline, GB, or GB + tunicamycin (TM; ER stress activator) for seven consecutive days, respectively. Apoptosis was assayed by determining the Bax/Bcl-2 ratio and caspase-3 level. Endoplasmic reticulum (ER) stress markers (CHOP, GRP78, and caspase-12) were detected by Western blot analysis. Oxidative stress was assessed by measuring the superoxide dismutase activity (SOD) and malondialdehyde (MDA), heme oxygenase-1(HO-1), and nuclear factor erythroid-2-related factor 2 (Nrf2) mRNA levels in the flaps. The percentage flap survival area and blood flow were assessed on postoperative day (POD) 7. Angiogenesis was visualized by hematoxylin and eosin and CD34 staining on POD 7. Results: GB increased the survival of perforator flaps, the flap survival area of GB, GB + TM, and control groups was 90.83 ± 1.93%, 70.93 ± 4.13%, and 62.97 ± 6.50%. GB decreased the Bax/Bcl-2 ratio and caspase-3 level. ER stress-related proteins were downregulated by GB. GB also decreased the MDA level and increased SOD activity, HO-1 and Nrf2 mRNA levels in the flaps. Further, GB induced regeneration of vascular vessels in comparison with saline or GB + TM. Conclusions: GB increased angiogenesis and alleviated oxidative stress by inhibiting ER stress, which increased the survival of perforator flaps. In contrast, GB + TM alleviated angiogenesis and induced oxidative stress by activating ER stress and decreasing the survival of perforator flaps.

The Effect of Leonurine on Multiterritory Perforator Flap Survival in Rats.

BACKGROUND: Leonurine (Leo), a natural active compound of Leonurus cardiaca, has been shown to possess various biological activities. However, it is not known whether Leo promotes perforator flap survival. METHODS: In this study, a perforator flap was outlined in the rat dorsum. The rats that survived surgery were divided randomly to control and Leo groups (n = 36 per group). Flap viability, flap perfusion, and level of protein linked with oxidative stress, cell apoptosis, and angiogenesis were evaluated. RESULTS: Relative to control group, the Leo group showed significantly higher the flap survival percentage (70.5% versus 90.2%, P < 0.05) and blood perfusion (197.1 versus 286.3, P < 0.05). Leo also increased 1.8-fold mean vessel density and upregulated 2.1-fold vascular endothelial growth factor protein expression compared with the control group, both of which indicate increased angiogenesis. Moreover, it significantly inhibited apoptosis by lowering caspase-3 activity. Superoxide dismutase expression was remarkably elevated in Leo group compared with the control group (56.0 versus 43.2 U/mg/protein, P < 0.01), but malondialdehyde quantities were significantly lower in the Leo group compared with control group (41.9 versus 57.5 nmol/mg/protein, P < 0.05). CONCLUSIONS: Leo may serve as an effective drug for improving perforator flap survival in rats via antioxidant and antiapoptotic mechanisms and promotion of angiogenesis.

Comparative proteomes change and possible role in different pathways of microRNA-21a-5p in a mouse model of spinal cord injury.

Our previous study found that microRNA-21a-5p (miR-21a-5p) knockdown could improve the recovery of motor function after spinal cord injury in a mouse model, but the precise molecular mechanism remains poorly understood. In this study, a modified Allen's weight drop was used to establish a mouse model of spinal cord injury. A proteomics approach was used to understand the role of differential protein expression with miR-21a-5p knockdown, using a mouse model of spinal cord injury without gene knockout as a negative control group. We found that after introducing miR-21a-5p knockdown, proteins that played an essential role in the regulation of inflammatory processes, cell protection against oxidative stress, cell redox homeostasis, and cell maintenance were upregulated compared with the negative control group. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis identified enriched pathways in both groups, such as the oxidative phosphorylation pathway, which is relevant to Parkinson's disease, Huntington's disease, Alzheimer's disease, and cardiac muscle contraction. We also found that miR-21a-5p could be a potential biomarker for amyotrophic lateral sclerosis, as miR-21a-5p becomes deregulated in this pathway. These results indicate successful detection of some important proteins that play potential roles in spinal cord injury. Elucidating the relationship between these proteins and the recovery of spinal cord injury will provide a reference for future research of spinal cord injury biomarkers. All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Shandong University of China on March 5, 2014.

Knockdown of MicroRNA-21 Promotes Neurological Recovery After Acute Spinal Cord Injury.

To assess the therapeutic effects of microRNA-21 (miR-21) knockdown (KD) for acute thoracic spinal cord contusion using a mouse model. Forty C57/BL6 mice were randomly divided into four groups: mice in the sham-operated (Sham) group received surgical procedure without spinal cord contusion; the spinal cord injury (SCI) group mice underwent spinal cord contusion without treatment; mice in the miR-21 KD group underwent spinal cord contusion followed by a single dose subdural injection of miR-21 KD vectors (1 × 107 TU); and the negative control (NC) group mice were given subdural injection of comparable amount of NC vectors (1 × 107 TU) after spinal cord contusion. The Basso Mouse Scale (BMS) was employed to assess hindlimb motor functions. Hematoxylin-eosin and Luxol fast blue staining were performed to evaluate pathologic changes in spinal cord tissues. Peripheral blood serum levels of tumor necrosis factor α (TNFα), transforming growth factor ß (TGF-ß) and interleukin-1ß (IL-1ß) were determined by the enzyme-linked immunosorbent assay, and mRNA expression of Brain derived neurotrophic factor (BDNF) was examined by reverse transcription-polymerase chain reaction (RT-PCR). Western blotting was performed to analyze the AKT signaling pathway. KD of miRNA-21 effectively improved the BMS scores at day 14 post-surgery compared with the SCI group (p < 0.01). The spinal cord tissue in the miR-21 KD group displayed the most overt histologic signs of recovery, with axonal regeneration and the recovery of neuronal morphology at day 14 post-surgery. Significantly alleviation of TGF-ß1, TNF-α and IL-1ß was also found in sera from the miR-21 inhibition group in comparison to others, whereas BDNF gene expression was upregulated following miR-21 KD (p < 0.01). Further, significantly decreased AKT phosphorylation activity was illustrated in the miR-21 KD group (p < 0.001). The data suggest that miR-21 KD significantly reduces the inflammatory response at the damaged spinal cord site and promotes motor functional recovery. The treatment also elevated expression of BDNF, a neurotrophin participating in nerve regeneration.

Long noncoding RNA maternally expressed gene 3 knockdown alleviates lipopolysaccharide-induced inflammatory injury by up-regulation of miR-203 in ATDC5 cells.

BACKGROUND: Osteoarthritis (OA) is a common degenerative joint disease, which seriously impacts the health of elderly. However, there is no effective treatment for curing this disease until now. Numerous studies reported that long noncoding RNAs (lncRNAs) are closely related to the pathogenesis of OA. Therefore, the study aims to investigate the effect of maternally expressed gene 3 (MEG3) on lipopolysaccharide (LPS)-induced inflammatory injury of ATDC5 cells. METHODS: Different concentrations (0, 1, 5, and 10 µg/ml) of LPS were used to induce ATDC5 cells injury. The specific expressing vectors were then transfected into ATDC5 cells to alter MEG3, Sirt1 and miR-203 expressions. Flow cytometry, luciferase reporter, qRT-PCR and western blot assays were used to detect cell viability, apoptosis, and the expressions of apoptosis-related proteins and pro-inflammatory factors (IL-1ß, IL-6, IL-8 and TNF-α). Meanwhile, ELISA was used for analyzing the concentrations of inflammatory cytokines in culture supernatant. Besides, the key pathways of PI3K/AKT and NF-κB were examined by western blot. RESULTS: LPS decreased cell viability, increased cell apoptosis, promoted the release of pro-inflammatory factors, and down-regulated MEG3 expression, Moreover, MEG3 knockdown alleviated LPS-induced inflammatory injury. MEG3 acted as a competing endogenous RNAs (ceRNA) for miR-203, and MEG3 knockdown reduced inflammatory injury by regulating miR-203. Furthermore, miR-203 positively regulated Sirt1 expression, and Sirt1 alleviated LPS-induced inflammatory injury via mediating PI3K/AKT and NF-κB pathways. CONCLUSION: This study showed that MEG3 knockdown alleviated LPS-induced inflammatory injury in ATDC5 cells by regulating miR-203 expression. Hence, the findings may offer a potential treatment perspective of OA.

Surgically­induced mouse models in the study of bone regeneration: Current models and future directions (Review).

Bone regeneration has been extensively studied over the past several decades. The surgically­induced mouse model is the key animal model for studying bone regeneration, of the various research strategies used. These mouse models mimic the trauma and recovery processes in vivo and serve as carriers for tissue engineering and gene modification to test various therapies or associated genes in bone regeneration. The present review introduces a classification of surgically induced mouse models in bone regeneration, evaluates the application and value of these models and discusses the potential development of further innovations in this field in the future.

ß-Aescin shows potent antiproliferative activity in osteosarcoma cells by inducing autophagy, ROS generation and mitochondrial membrane potential loss.

PURPOSE: Osteosarcoma is one of the frequent bone tumor affecting mainly children and is associated with considerable mortality. The limited availability of anticancer drugs and less efficacious treatment options have led to poor survival rates of patients with osteosarcoma. Therefore, there is need to look for more viable treatment options and against this backdrop, natural products may prove handy. Therefore the aim of the present study was to evaluate the anticancer activity of a natural product of plant origin, ß-aescin, against U2OS human osteosarcoma cells. METHODS: U205 human osteosarcoma cell line was used in this study. Antiproliferative activity was determined by MTT assay. Reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were evaluated by flow cytometry. Autophagy was detected by monodansylcadaverine (MDC) staining and immunofluorescence. Protein expression was examined by western blotting. RESULTS: The results indicated that ß-aescin showed significant anticancer activity against U2OS human osteosarcoma cells and exhibited an IC50 of 40 µM. ß-aescin treatment caused significant increase in ROS and decrease in the MMP. The anticancer effect of ß-aescin was found to be due mainly to autophagic cell death as evidenced from MDC staining and immunofluorescence. Moreover, ß-aescin caused significant increase in the expression levels of LC3- II protein in U2OS osteosarcoma cells in a time and dosedependent manner. CONCLUSION: Taken together we propose that ß-aescin may prove a lead molecule in the management of osteosarcoma and deserves further research efforts.

Regulatory roles of microRNA-21 in fibrosis through interaction with diverse pathways (Review).

MicroRNA-21 (miR-21) is a small, non-coding RNA which can regulate gene expression at the post­transcriptional level. While the fibrogenic process is vital in tissue repair, proliferation and transition of fibrogenic cells combined with an imbalance of secretion and degradation of the extracellular matrix results in excessive tissue remodeling and fibrosis. Recent studies have indicated that miR­21 is overexpressed during fibrosis and can regulate the fibrogenic process in a variety of organs and tissues via diverse pathways. The present review summarized the significant roles of miR-21 in fibrosis and discussed the underlying key pathways.

Macrophage Polarization in IL-10 Treatment of Particle-Induced Inflammation and Osteolysis.

This study investigated the therapeutic influence and potential mechanism of IL-10 in ameliorating orthopedic debris particle-induced inflammation and osteolysis. A murine air pouch with bone implantation and polyethylene particles was also used to evaluate the therapeutic effects of IL-10. The data suggested that the particle challenges significantly promoted macrophage activation and osteoclastogenesis, with dramatically increased macrophage infiltration into the pouch membranes and elevated tartrate-resistant acid phosphatase-positive cell deposition. Immunohistochemical stains revealed a significantly higher ratio of induced nitric oxide synthase-expressing cells in the particle-challenged group; treatment with IL-10 resulted in marked switching to CD163(+) cells. Also, IL-10 effectively reduced tartrate-resistant acid phosphatase-positive stained cells in the pouch membranes, and minimized the bone mineral density loss compared with untreated samples. Real-time PCR and Western blot examination indicated that IL-10 treatment significantly diminished the particle-induced IL-1ß expression but promoted expression of CD163, transforming growth factor-ß1, and CCR2. Furthermore, IL-10 significantly inhibited the ultra-high-molecular-weight polyethylene particle-elevated phospho-STAT1 and phospho-NF-κB p65 productions, and promoted phospho-STAT3 expression. Overall, the data indicate the pivotal effects of IL-10 on macrophage polarization. The effects of IL-10 in ameliorating local inflammation and osteolysis may be associated with macrophage polarization through the up-regulation of the Janus activating kinase/STAT3 signaling pathway, and the down-regulation of NF-κB and Janus activating kinase/STAT1 expression.

Microarray based analysis of gene regulation by microRNA in intervertebral disc degeneration.

The present study aimed to explore the underlying mechanism of the development of intervertebral disc degeneration (IDD) by bioinformatics based on microarray datasets. GSE 19943 and GSE 34095 datasets downloaded from Gene Expression Omnibus data were used to screen the differentially expressed genes (DEGs) in IDD. The correlation between microRNAs and target genes was investigated using different algorithms. The underlying molecular mechanisms of the target genes were then explored using Kyoto Encyclopedia of Genes and Genomes pathway and Gene Ontology function enrichment analysis. A total of 9 differentially expressed microRNAs, including 3 down­ and 6 upregulated microRNAs and 850 DEGs were identified in tissue from patients with IDD. Two regulation networks of the target genes by microRNAs were constructed, including 33 upregulated microRNA­target gene pairs and 4 downregulated microRNA­target gene pairs. Certain target genes had been demonstrated to be involved in IDD progression via various pathways, including in the cell cycle and pathways in cancer. In addition, two important microRNAs (microRNA­222 and microRNA­589) were identified that were pivotal for the development of IDD, and their target genes, CDKNAB and SMAD4. In conclusion, a comprehensive miRNA­target gene regulatory network was constructed, which was found to be important in IDD progression.

Antigen-specific tolerogenic dendritic cells ameliorate the severity of murine collagen-induced arthritis.

Dendritic cells (DCs) play important roles in initiation of the pathogenic processes of autoimmune disorders, such as rheumatoid arthritis (RA). Tolerogenic dendritic cells (tolDCs) are generated from naïve DCs and induce T cell tolerance; thus, they represent a promising strategy for specific cellular therapy for autoimmune diseases. In this study, we generated green fluorescent protein (GFP)-labeled tolDCs and confirmed their phenotypes and biological functions. We found that tolDCs suppressed the memory lymphocyte response and exhibited strong tolerogenic potential; thus, these cells show promise for the treatment of autoimmune diseases. Additionally, a collagen-induced arthritis (CIA) mouse model was used to test the role of tolDCs in vivo. The results of a further mechanistic experiment revealed that tolDCs suppressed inflammatory arthritis at least partially by up-regulating regulatory T (Treg) cells. Collectively, our data suggest that tolDCs may be used as a promising alternative therapy for inflammatory arthritis.

Biological responses of preosteoblasts to particulate and ion forms of Co-Cr alloy.

This study compared the particulate and ion forms of a cobalt-chrome (Co-Cr) alloy on the differentiation/activation of preosteoblasts. Mouse preosteoblasts (MC3T3-E1) were cultured in an osteoblast-induction medium in the presence of particulate and ion forms of a Co-Cr alloy, followed by cell proliferation and cytotoxicity evaluations. The maturation and function of osteoblasts were assessed by alkaline phosphatase (ALP) assay and related gene expressions. Both particulate and ion forms of the metals significantly reduced the proliferation of MC3T3-E1 cells in a dose-dependent manner. Similarly, cells challenged with high concentrations of particles and ions exhibited a marked cytotoxic effect and diminished expression of ALP. Real-time (RT) polymerase chain reaction (PCR) data have suggested that cells with Co-Cr particles dramatically promoted over-expression of monocyte chemo-attractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6), whereas Co(2+) ions treatment predominately up-regulated expressions of receptor activator of nuclear factor kappa-B ligand (RANKL), nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), and down-regulated expression of osteoprotegerin (OPG) and Osterix (Osx). Overall, this study provides evidence that both Co-Cr alloy particles and metal ions interfered with the MC3T3-E1 cells for their growth, maturation, and functions. Further, Co-Cr particles exhibited stronger effects on inflammatory mediators, while metal ions showed more influence on inhibition of osteoblast differentiation and promotion of osteoclastogenesis.

Progranulin knockout accelerates intervertebral disc degeneration in aging mice.

Intervertebral disc (IVD) degeneration is a common degenerative disease, yet much is unknown about the mechanisms during its pathogenesis. Herein we investigated whether progranulin (PGRN), a chondroprotective growth factor, is associated with IVD degeneration. PGRN was detectable in both human and murine IVD. The levels of PGRN were upregulated in murine IVD tissue during aging process. Loss of PGRN resulted in an early onset of degenerative changes in the IVD tissue and altered expressions of the degeneration-associated molecules in the mouse IVD tissue. Moreover, PGRN knockout mice exhibited accelerated IVD matrix degeneration, abnormal bone formation and exaggerated bone resorption in vertebra with aging. The acceleration of IVD degeneration observed in PGRN null mice was probably due to the enhanced activation of NF-κB signaling and ß-catenin signaling. Taken together, PGRN may play a critical role in homeostasis of IVD, and may serve as a potential molecular target for prevention and treatment of disc degenerative diseases.

Genetic polymorphisms of interleukin-16 are associated with susceptibility to primary knee osteoarthritis.

Interleukin-16 (IL-16) polymorphisms have been associated with various disease states, and its activity is dysregulated in synovial fibroblasts of individuals with rheumatoid arthritis. Here, the association between genetic polymorphisms in the gene encoding IL-16 and susceptibility to primary knee osteoarthritis was investigated in the Chinese Han population. The study included 228 unrelated patients, half of whom presented with primary knee osteoarthritis (OA); the remainder was healthy individuals. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to examine single nucleotide polymorphisms (SNPs) in IL16 in these patients. Statistical analysis was performed using the chi-square goodness-of-fit test, Hardy-Weinberg (H-W) equilibrium, linkage disequilibrium analysis, and logistic regression analysis. The genotype distributions of three IL16 SNPs, rs11556218, rs4778889, and rs4072111, were found to be in line with Hardy-Weinberg equilibrium criteria (P > 0.05). The single-factor logistic regression analysis showed that, compared with the T/T genotype, the T/G genotype decreased the risk of primary knee OA in rs11556218 (OR = 0.37, 95% CI = 0.18~0.82) and, compared with the C/C genotype, the C/T genotype increased the risk of primary knee OA in rs4072111 (OR = 1.83, 95% CI = 1.07~3.59). There was linkage disequilibrium between rs4778889 and rs11556218 (D= 0.592, r(2) = 0.213). Finally, logistic regression analysis showed that compared to haplotype TTC, the TTT haplotype was associated with an increased risk of primary knee OA (OR = 2.10, 95% CI = 1.09-4.98); however, the GCC haplotype was associated with a reduced risk of primary knee OA (OR = 0.36, 95% CI = 0.12-0.93). Thus, the genetic polymorphisms rs11556218, rs4778889, and rs4072111 in the gene encoding IL-16 are associated with primary knee OA in Chinese Han population.

Molecular mechanism underlying the tumor-promoting functions of carcinoma-associated fibroblasts.

Tumor microenvironment is composed of all the untransformed elements in the vicinity of tumor, mainly including a large number of stromal cells and extracellular matrix proteins, which play an active role in most solid tumor initiation and progression. Carcinoma-associated fibroblasts (CAFs), one of the most common stromal cell types in the tumor microenvironment, have been demonstrated to be involved in tumor growth, invasion, and metastasis. Therefore, they are becoming a promising target for anti-cancer therapies. In this review, we firstly summarize the current understandings of CAFs' molecular biology, including the heterogeneous cellular origins and molecular markers, and then, we focus on reviewing their various tumor-promoting phenotypes involved in complex mechanisms, which can be summarized to the CAF-conveyed paracrine signals in tumor cells, cancer stem cells, and metastasis-initiating cancer cells, as well as the CAF-enhanced extrinsic tumor-promoting processes including angiogenesis, extracellular matrix remodeling, and tumor-related inflammation; finally, we describe the available directions of CAF-based target therapy and suggest research areas which need to be further explored so as to deepen the understanding of tumor evolution and provide new therapeutic targets for cancer treatment.

Expression of hepatocyte growth factor and c-Met in non-small-cell lung cancer and association with lymphangiogenesis.

Previous experimental studies have demonstrated that hepatocyte growth factor (HGF) and its receptor c­Met serve an important function in lymphangiogenesis, but their biological functions in malignant tumors have remained elusive. The present study aimed to investigate the expression patterns of HGF­α and c­Met and their association with vascular endothelial growth factor (VEGF)­C, lymphatic vessel density and lymph node metastasis in non­small­cell lung cancer (NSCLC). In the present study, the lymphatic microvessel density (LMVD) and the expression levels of HGF­α, its receptor c­Met and VEGF­C were determined in 113 human NSCLC tissues and 113 normal lung tissue samples, using immunohistochemical staining. As a result, it was determined that the expression levels of HGF­α, c­Met and VEGF­C were significantly higher in NSCLC tissues than those in normal lung tissues (HGF­α, 67.3 vs. 20.4%, P<0.001; c­Met, 74.3 vs. 23.0%, P<0.001; and VEGF­C, 65.5 vs. 23.9%, P<0.001). HGF­α expression was observed to be significantly associated with that of VEGF­C (r=0.234, P=0.012) or c­Met (r=0.648, P<0.001). In addition, there was a positive correlation between the expression levels of VEGF­C and c­Met (r=0.224, P=0.017). In NSCLC tissues, the expression of HGF­α, c­Met or VEGF­C was significantly correlated with the LMVD (P=0.045, 0.002 and 0.001, respectively), and lymph node metastasis was more common in HGF­α, c­Met or VEGF­C­positive groups (P=0.020, 0.020 and 0.009, respectively). In addition, the HGF­α or VEGF­C­positive groups presented shorter survival time periods. In conclusion, the expression of HGF­α or c­Met was closely correlated with VEGF­C, LMVD and metastases of lymph nodes, indicating that HGF­α, c­Met and VEGF­C may perform important and collaborative actions in lymphangiogenesis and lymphatic metastasis of primary NSCLC.