BACKGROUND: There is growing evidence that 5-fluorouracil (5-FU) combined with therapeutic trauma can effectively induce skin repigmentation in vitiligo patients who are unresponsive to conventional treatments. Previous studies have mainly focused on identifying the antimitotic activity of 5-FU for the treatment of skin cancer, but few studies have investigated its extra-genotoxic actions favoring melanocyte recruitment. METHODS: We utilized the full thickness excisional skin wound model in Dct-LacZ transgenic mice to dynamically assess the migration of melanocytes in the margins of wounds treated with or without 5-FU. The in-situ expression of CXCL12 was examined in the wound beds using immunofluorescence staining. Quantitative real-time polymerase chain reaction and Western blotting analyses were performed to detect the expression levels of CXCL12 mRNA and protein in primary mouse dermal fibroblasts treated with or without 5-FU. Transwell assays and fluorescein isothiocyanate (FITC)-phalloidin staining were used to observe cell migration and filamentous actin (F-actin) changes of melan-a murine melanocytes. RESULTS: Whole mount and cryosection X-gal staining showed that the cell numbers of LacZ-positive melanocytes were much higher in the margins of dorsal and tail skin wounds treated with 5-FU compared with the controls. Meanwhile, CXCL12 immunostaining was significantly increased in the dermal compartment of wounds treated with 5-FU (control vs. 5-FU, 22.47 ± 8.85 vs. 44.69 ± 5.97, P < 0.05). Moreover, 5-FU significantly upregulated the expression levels of CXCL12 mRNA (control vs. 5-FU, 1.00 ± 0.08 vs. 1.54 ± 0.06, P < 0.05) and protein (control vs. 5-FU, 1.00 ± 0.06 vs. 2.93 ± 0.10, P < 0.05) in cultured fibroblasts. Inhibition of the CXCL12/CXCR4 axis suppressed melanocyte migration in vitro using a CXCL12 small interfering RNA (siRNA) or a CXCR4 antagonist (AMD3100). CONCLUSION 5-FU possesses a pro-pigmentary activity through activation of the CXCL12/CXCR4 axis to drive the chemotactic migration of melanocytes.
Animals ; Cell Movement ; Cell Proliferation ; Chemokine CXCL12/genetics* ; Fibroblasts ; Fluorouracil/therapeutic use* ; Humans ; Mice ; RNA, Messenger ; Receptors, CXCR4

OBJECTIVE: To investigate the role of IL-17A in promoting the activation of lung fibroblasts and the secretion of chemokine CXCL12, and to explore the possible mechanism. METHODS: Lung tissues of BALB/c mice were collected after intraperitoneal injection of recombinant mouse IL-17A (rmIL-17A). Real-time RT-PCR and Western blotting were used to detect the expression levels of α-smooth muscle actin (α-SMA) and collagen I in lung tissues, and immunohistochemical staining and real-time RT-PCR were used to determine the expression of CXCL12. Normal mouse primary lung fibroblasts were isolated and cultured, and identified by immunofluorescence staining with optical microscopy. Cells and supernatant of culture medium were collected after stimulation with rmIL-17A at different concentrations. mRNA levels of α-SMA, collagen I, and CXCL12 in the cells were determined by real-time RT-PCR, and the levels of collagen I and CXCL12 in the supernatant of culture medium were determined by ELISA. RESULTS: The mRNA and protein levels of α-SMA and collagen I in the lung tissue of mice injected with rmIL-17A were significantly increased compared with the control group (all CONCLUSIONS s: IL-17A can promote the activation of lung fibroblasts and translation into myofibroblast. The secretion of collagen is increased, which promote the deposition of extracullular matrix, and leads to the occurrence and development of lung fibrosis. CXCL12, a chemokine secreted by activated fibroblasts, may be involved in this process.
Actins/genetics* ; Animals ; Cells, Cultured ; Chemokine CXCL12/metabolism* ; Fibroblasts/metabolism* ; Interleukin-17/pharmacology* ; Lung/metabolism* ; Mice ; Mice, Inbred BALB C

BACKGROUND: The epidermal growth factor receptor (EFGR) mutation was closely related to the invasion and metastasis of lung adenocarcinoma and the biological axis of CXCR4/CXCL12 (chemokine receptor 4/chemokine ligand 12) played an important role in the organ-specific metastasis of the tumor. It was a question surrounding whether there is interaction between them in the process of lung adenocarcinoma metastasis. To investigate the potential molecular mechanisms of EGFR over-expression and EFGR-mutations effects on cell proliferation, migration and invasion, we constructed EGFR over-expression and three EFGR-mutant human lung adenocarcinoma H1299 cell sublines. METHODS: EGFR over-expression and three EFGR-mutant (EGFR-E746-A750del, EGFR-T790M and EGFR-L858R) plasmid were designed and transfected H1299 cells with Lipofectamine 2000. H1299 cells transfected with empty vector were negative control (NC), and H1299 cells without transfection were set as blank control (BC). The effects of EGFR over-expression and mutations on the proliferation, migration and invasion of H1299 cells were detected by cell cloning assay, wound healing assay and Transwell assay. The mRNA and protein expression levels of MMP-2, MMP-9, CXCR4 and CXCL12 were detected by RT-PCR and Western blot. RESULTS: Compared with negative control group and blank control group, EGFR over-expression and EGFR-E746-A750 deletion have significantly higher colony formation (28±2, 28.33±4.16; respectively) (P<0.05) and the cell migration and invasion ability were significantly increased (P<0.05). RT-PCR and Western blot assay showed that the mRNA and protein expression of MMP-2, MMP-9, CXCR4 and CXCL12 in EGFR over-expression and EGFR-E746-A750 deletion group were remarkably higher than that in negative control and blank control group (P<0.05). CONCLUSIONS EGFR over-expression and 19 exon deletion can promote the expression of MMP-2 and MMP-9 by up-regulating CXCR4/CXCL12 signaling pathway, leading to the change of tumor biological characteristics such as higher proliferation, migration and invasion ability.
Adenocarcinoma ; pathology ; Adenocarcinoma of Lung ; Cell Line, Tumor ; Cell Movement ; genetics ; Chemokine CXCL12 ; metabolism ; ErbB Receptors ; genetics ; Gene Expression Regulation, Neoplastic ; Humans ; Lung Neoplasms ; pathology ; Mutation ; Neoplasm Invasiveness ; Receptors, CXCR4 ; metabolism ; Signal Transduction ; genetics

Chemokine 12 (CXCL12), also known as stromal cell derived factor-1 (SDF-1) and a member of the CXC chemokine subfamily, is ubiquitously expressed in many tissues and cell types. It interacts specifically with the ligand for the transmembrane G protein-coupled receptors CXCR4 and CXCR7. The CXCL12/CXCR4 axis takes part in a series of physiological, biochemical, and pathological process, such as inflammation and leukocyte trafficking, cancer-induced bone pain, and postsurgical pain, and also is a key factor in the cross-talking between tumor cells and their microenvironment. Aberrant overexpression of CXCR4 is critical for tumor survival, proliferation, angiogenesis, homing and metastasis. In this review, we summarized the role of CXCL12/CXCR4 in cancer, CXCR4 inhibitors under clinical study, and natural product CXCR4 antagonists. In conclusion, the CXCL12/CXCR4 signaling is important for tumor development and targeting the pathway might represent an effective approach to developing novel therapy in cancer treatment.
Animals ; Antineoplastic Agents ; chemical synthesis ; chemistry ; pharmacology ; Biological Products ; chemistry ; pharmacology ; Chemokine CXCL12 ; genetics ; metabolism ; Humans ; Molecular Targeted Therapy ; Neoplasms ; drug therapy ; genetics ; metabolism ; Receptors, CXCR4 ; antagonists & inhibitors ; genetics ; metabolism

OBJECTIVE: To investigate the association of CXCL12 and CXCR4 polymorphisms with the genetic risk and severity of coronary stenosis in patients with coronary artery disease (CAD). METHODS: Competitive allele specific PCR(KASP) was performed to identify the genotypes of rs2297630 and rs2322864 polymorphisms in 302 CAD patients and 302 age-and gender-matched healthy controls. The severity of CAD patients was assessed by the Gensini scoring system according to the results of coronary arteriography. The association of rs2297630 and rs2322864 polymorphisms with genetic risk of CAD and Gensini scores were analyzed by unconditional logistic regression and multivariate linear regression respectively. RESULTS: There were significant differences in the genotype and allele frequencies of both rs2297630 and rs2322864 between the CAD group and healthy control (all <0.01). Regression analysis showed that rs2297630 polymorphism was associated with genetic risk of CAD and Gensini scores (all <0.01). People who carried the AA genotype suffered higher risk of CAD susceptibility and more serious coronary stenosis (all <0.01), compared with GG genotype carriers. There was also significant association between rs2322864 polymorphism and genetic risk of CAD (<0.01); those who carried the CT genotype had higher risk of CAD (<0.01), compared with TT genotype carriers. However, rs2322864 polymorphism was not associated with the severity of coronary stenosis (>0.05). CONCLUSIONS Gene polymorphism of CXCL12 rs2297630 is associated with the genetic risk of CAD and the severity of coronary stenosis. Moreover, the gene polymorphism of CXCR4 rs2322864 is associated with genetic risk of CAD, but not with the severity of coronary stenosis.
Chemokine CXCL12 ; genetics ; Coronary Angiography ; Coronary Artery Disease ; complications ; Coronary Stenosis ; complications ; genetics ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Polymorphism, Genetic ; Receptors, CXCR4 ; genetics ; Risk Factors

Many studies have reported the relationship between CXCL12 G801A polymorphism and cancer risk, with conflicting results. In this study, we tried to clarify the possibility that this polymorphism may increase cancer risk by conducting an updated meta-analysis. PubMed and EMbase were searched for case-control studies regarding the association of the gene polymorphism and cancer risk. Data were extracted and odds ratios (ORs) with 95% confidence intervals (95% CIs) were used to assess the strength of the association. Heterogeneity among articles and publication bias was also assessed. Significantly increased risk for cancer was found (A vs. G: OR=1.26, 95% CI=1.13-1.40, P<0.01; AA+AG vs. GG: OR=1.33, 95% CI=1.16-1.52, P<0.01). In subgroup analysis, statistically elevated cancer risk was found in both Asian and Caucasian populations (for Asian, AA+AG vs. GG: OR=1.74, 95% CI=1.22-2.47, P<0.01; for Caucasian, AA+AG vs. GG: OR=1.24, 95% CI=1.09-1.42, P<0.01). Our result indicated that CXCL12 G801A polymorphism is a risk factor for cancer. To validate the finding, further large-size case-control studies are warranted.
Asian Continental Ancestry Group ; genetics ; Chemokine CXCL12 ; genetics ; European Continental Ancestry Group ; genetics ; Genetic Predisposition to Disease ; Humans ; Neoplasms ; ethnology ; genetics ; pathology ; Odds Ratio ; Polymorphism, Single Nucleotide

OBJECTIVETo study the effect of Buyang Huanwu decoction (BYHWD) inducing angiogenesis on the neuroblast migration from the subventricular zone and its mechanisms after focal cerebral ischemia.

METHODThe middle cerebral artery occlusion (MCAO) was performed to mice for 30 minutes to establish the model. The rats were divided into sham group, model group, BYHWD group and endostatin group. BYHWD (20 g x kg(-1), ig) and endostatin (10 μg, sc) were administered 24 h after ischemia once a day for consecutively 14 days. At 14 d after ischemia, the density of micro-vessel and the number of neuroblasts in the ischemia border zone were determined by immunofluorescence staining. The mRNA and protein expression of cell-derived factor-1 (SDF-1) and brain-derived neurotrophic (BDNF) were examined by real-time PCR and Western blot.

RESULTCompared with the model group, BYHWD significantly increased the density of micro-vessel and the number of DCX positive cells in the ischemia border zone (P < 0.01), and significantly increased the SDF-1 and BDNF mRNA and protein expression (P < 0.01). Compared with BYHWD group, endostatin significantly reduced the density of micro-vessel and the number of DCX positive cells in the ischemia border zone (P < 0.01), as well as the SDF-1, BDNF mRNA and protein expression (P < 0.01).

CONCLUSIONBYHWD could promote the neuroblast migration from the subventricular zone via inducing angiogenesis after cerebral ischemia, the mechanism may be correlated with up-regulating the expression of SDF-1 and BDNF.

Angiogenesis Inducing Agents ; pharmacology ; Animals ; Brain Ischemia ; pathology ; physiopathology ; Brain-Derived Neurotrophic Factor ; analysis ; genetics ; Cell Movement ; drug effects ; Cerebral Ventricles ; pathology ; Chemokine CXCL12 ; analysis ; genetics ; Drugs, Chinese Herbal ; pharmacology ; Male ; Mice ; Mice, Inbred ICR ; Neurons ; drug effects ; physiology

Stromal cells provide a crucial microenvironment for overlying epithelium. Here we investigated the expression and function of a stromal cell-specific protein, stromal cell-derived factor-1 (SDF-1), in normal human skin and in the tissues of diseased skin. Immunohistology and laser capture microdissection (LCM)-coupled quantitative real-time RT-PCR revealed that SDF-1 is constitutively and predominantly expressed in dermal stromal cells in normal human skin in vivo. To our surprise, an extremely high level of SDF-1 transcription was observed in the dermis of normal human skin in vivo, evidenced by much higher mRNA expression level than type I collagen, the most abundant and highly expressed protein in human skin. SDF-1 was also upregulated in the tissues of many human skin disorders including psoriasis, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC). Double immunostaining for SDF-1 and HSP47 (heat shock protein 47), a marker of fibroblasts, revealed that fibroblasts were the major source of stroma-cell-derived SDF-1 in both normal and diseased skin. Functionally, SDF-1 activates the ERK (extracellular-signal-regulated kinases) pathway and functions as a mitogen to stimulate epidermal keratinocyte proliferation. Both overexpression of SDF-1 in dermal fibroblasts and treatment with rhSDF-1 to the skin equivalent cultures significantly increased the number of keratinocyte layers and epidermal thickness. Conversely, the stimulative function of SDF-1 on keratinocyte proliferation was nearly completely eliminated by interfering with CXCR4, a specific receptor of SDF-1, or by knock-down of SDF-1 in fibroblasts. Our data reveal that extremely high levels of SDF-1 provide a crucial microenvironment for epidermal keratinocyte proliferation in both physiologic and pathologic skin conditions.
Adult ; Cell Proliferation ; Chemokine CXCL12 ; genetics ; Epidermal Cells ; Epidermis ; pathology ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Fibroblasts ; metabolism ; Gene Expression Regulation ; Humans ; Keratinocytes ; cytology ; pathology ; Signal Transduction ; Skin Diseases ; genetics ; pathology

This study was purposed to establish the mesenchymal stem cells (MSCs) stably overexpressing mouse CXC chemokine receptor type 4 (CXCR4) gene and to explore their function. The recombinant lentiviral vector LV-CXCR4-IRES-EGFP with packaging plasmid pSPAX2 and envelope plasmid pMD.2G were co-transfected into 293FT packaging cell line using lipofectamine 2000 to produce the recombinant lentiviral vectors. The recombinant viruses were harvested and concentrated by using ultracentrifugation. Mouse bone marrow MSC were infected with the viral supernatants. Variable methods were used to optimize the transduction condition. EGFP expression was visualized using fluorescence microscope and efficiency of infection was determined by flow cytometry (FCM). Proliferation and apoptosis were detected by proliferation curve and FCM, respectively. Migration capacity was assessed by a chemotaxis assay using transwell. Expression of EGFP were detected by fluorescence microscopy in MSCs after infection. The results showed that through optimization of infection condition, the recombination lentiviral vectors had higher infection efficacy; after infection for 72 h, the higher expression of EGFP could be observed under fluorescence microscope; the expression of CXCR4 protein on MSC surface in CXCR4-MSC group significantly increased compared with those in the control group. Meanwhile, over-expression of CXCR4 had no effect on their capacity of proliferation and did not induce apoptosis. Moreover, CXCR4 enhanced the migration of cells in the transwell induced by SDF-1 gradient compared with the EGFP control group. It is concluded that the lentiviral vector can not only infect mouse MSCs efficiently, but also can make CXCR4 express stably in MSC.
Animals ; Apoptosis ; Cell Line ; Chemokine CXCL12 ; Flow Cytometry ; Genetic Vectors ; Lentivirus ; Mesenchymal Stromal Cells ; metabolism ; Mice ; Plasmids ; Receptors, CXCR4 ; genetics ; Transfection

OBJECTIVEThis review focuses on the state-of-the-art of CXCL12/CXCR4 signaling axis in pancreatic cancer and its role in tumor progression.

DATA SOURCESRelevant articles published in English were identified by searching in Pubmed from 1997 to 2013, with keywords "CXCL12", "CXCR4" and "pancreatic cancer". Important references from selected articles were also retrieved.

STUDY SELECTIONArticles about CXCL12/CXCR4 signaling axis in pancreatic cancer and relevant mechanisms were selected.

RESULTSPancreatic cancer has been one of the most lethal human malignancies, with median survival less than one year and overall 5-year survival only 6%. Tumor cells from pancreatic cancer express high level of CXCR4. CXCL12, the ligand for CXCR4, is extensively secreted by neighboring stromal cells and other distant organs. CXCL12 primarily binds to CXCR4, induces intracellular signaling through several divergent pathways, which are involved in progression and metastasis of pancreatic cancer.

CONCLUSIONSCXCL12/CXCR4 signaling axis may play an important role in the communication between pancreatic cancer cells and their microenvironment, which may have effect on tumor proliferation, invasion, angiogenesis, metastasis and chemoresistance. CXCL12/CXCR4 signaling axis may serves as a novel therapeutic target for pancreatic cancer.

Chemokine CXCL12 ; genetics ; metabolism ; Humans ; Pancreatic Neoplasms ; genetics ; metabolism ; Receptors, CXCR4 ; genetics ; metabolism ; Signal Transduction ; genetics ; physiology