OBJECTIVE: To evaluate the change of cell surface CXC chemokine receptor 4 (CXCR4) expression of stem cells from apical papilla (SCAP) after the inhibition of endocytotic pathway, thus to provide experimental basis for the mechanism of SCAP migration. METHODS: The immunofluorescence analysis was conducted to examine the co-expression of CXCR4 and endocytotic compartments, including early endosomes, recycling endosomes and lysosomes in SCAP. Several Rab proteins were applied as markers of organelles in the endocytotic pathway, including Rab5 for early endosomes, Rab11A for recycling endosomes, and Lamp1 for lysosomes. The co-localization of CXCR4 with these endodontic compartments was further observed by proximity ligation assay (PLA). SCAP was treated with two kinds of endocytotic inhibitors, Blebbistatin and Dynasore, at a concentration of 80 μmol/L, respectively. The conditioning time was 1 hour. Flow cytometry was carried out to evaluate the proportion of SCAP that expressed CXCR4 on cell surface. The data were analysed by analysis of variance (ANOVA). RESULTS: The red staining of CXCR4 on immunofluorescence confocal microscopy predominantly overlapped with the green staining of Rab5 and Rab11A, and partly overlapped with Lamp1. It indicated that most CXCR4 molecules were located in early endosomes and recycling endosomes, and some were located in lysosomes. The PLA results revealed that the co-localizaiton of CXCR4 with endocytotic compartments could be observed in early endosomes, recycling endosomes and lysosomes. According to the results of flow cytometry, the proportion of SCAP that expressed CXCR4 on cell surface was as low as 0.13%±0.10%. After the inhibition of endocytosis by pretreating the cells with the following two inhibitors, Blebbistatin and Dynasore, the percentage of SCAP that positively expressed CXCR4 on cell surface was significantly increased to 13.34%±1.31% in Blebbistatin group and 4.03%±0.92% in Dynasore group (F=16.721, P<0.001). Moreover, the number of SCAP that expressed CXCR4 on cell surface in Blebbistatin group was significantly higher than that in Dynasore group (P<0.001). CONCLUSION The inhibition of endocytotic pathway could increase the number of SCAP that expressed CXCR4 on cell surface, and provide potency for the migration of SCAP.
Endocytosis ; Endosomes ; Lysosomes ; Receptors, CXCR4 ; Stem Cells

AMD3100 (Plerixafor) is an antagonist of CXCR4, receptor for stromal cell-derived factor-1 (SDF-1).It disrupts binding of SDF-1 to CXCR4 by competing binding site, thus blocking the physiological function of SDF-1/CXCR4 axis. SDF-1/CXCR4 axis has been shown to play critical roles in stem cell mobilization, migration and homing, and in immunoregulation, inflammatory disease, autoimmune disorder, embryonic development, and tumor cell proliferation, migration and location. AMD3100 has been confined effective for the mobilization of HSC and MSC, inhibition of carcinoma growth and metastasis, suppression of some inflammatory and autoimmune disorder. Therefore, further research on AMD3100 will be helpful to understand the effects of bone marrow microenvironment on the pathogenesis of neoplasm, and to restore the traumatic tissues by mobilizing HSC effectively, that might provide a new idea and measure for the treatment of certain neoplasms. Some research progress of basic research and application on AMD3100 are summarized in this review.
Heterocyclic Compounds ; pharmacology ; Receptors, CXCR4 ; antagonists & inhibitors

Chemokine CXCL12 ; Child ; Humans ; Neoplasm Metastasis ; Neoplasms ; pathology ; Receptors, CXCR4

BACKGROUND: Tumor associated macrophages (TAMs) and CXC chemokine receptor 4 (CXCR4) have emerged as potential biomarkers in various human cancers. The aims of this study were to investigate the clinical characteristics of anaplastic thyroid cancer (ATC) patients according to the TAM numbers in the tumor tissue, and to evaluate the associations between CXCR4 expressions and macrophage densities in ATC tumor microenvironment. METHODS: Total 14 ATC samples from thyroid tissue microarray were used. Immunohistochemical staining was performed using anti-CD163 and anti-CXCR4 antibodies. According to the immunoreactivity of CD163, all subjects were divided into two groups: low-CD163 (n=8) and high-CD163 (n=6) groups. RESULTS: The mean diagnostic age was 65±7 years and the median tumor size was 4.3 cm, ranging 2.5 to 15 cm. Clinicopathological characteristics were not significantly different between low-CD163 and high-CD163 groups, while age of diagnosis was younger in high-CD163 group than that of low-CD163 group with marginal significance (56.9±5.5 years vs. 67.5±6.8 years, P=0.09). However, overall survival was significantly reduced in high-CD163 group (5.5 months [range, 1 to 10]) compared with low-CD163 groups (8.8 months [range, 6 to 121); log-rank test, P=0.0443). Moreover, high-CD163 group showed strong CXCR4 expressions in both cancer and stromal compartments, while low-CD163 group showed relatively weak, stromal-dominant CXCR4 expressions. Additionally, CD163 and CXCR4 expressions showed a strong positive correlation (γ²=0.432, P=0.013). CONCLUSION: Increased number of TAMs showed poor overall survival in ATC, suggesting TAMs are potentially a prognostic biomarker for ATC. CXCR4 expression was significantly correlated with CD163-positive TAM densities, which suggest the possible role of CXCR4 in TAM recruitments.
Antibodies ; Biomarkers ; Diagnosis ; Humans ; Macrophages* ; Receptors, CXCR* ; Receptors, CXCR4* ; Thyroid Carcinoma, Anaplastic* ; Thyroid Gland ; Tumor Microenvironment

BACKGROUND AND OBJECTIVES: Follicular tumors can present a difficult diagnostic challenge for cytological evaluation and ultrasound findings. Therefore, new methods which could help distinguish follicular adenoma from follicular carcinoma simply and accurately are greatly desired. This study investigated the usefulness of immnunohistochemical expression of CXC chemokine receptor 4 (CXCR4) and galectin-3 as marker of differentiated thyroid carcinomas. MATERIALS AND METHODS: Expression of CXCR4 and galectin-3 were examined immunohistochemically in the 60 paraffin embedded tissues which were already diagnosed as follicular adenoma (n=20), follicullar carcinoma (n=20), and papillary carcinoma (n=20) of thyroid. RESULTS: Galatin-3 was expressed significantly high in follicular carcinoma than follicular adenoma (p=0.022). CXCR4 was also expressed significantly high in follicular carcinoma than follicular adenoma (p=0.027). The sensitivity of CXCR4 and galectin-3 was 70% and 80% and specificity, 65% and 60% for differential diagnosis of follicular tumors. CONCLUSION: An immunohistochemical panel, including galatin-3 and CXCR4, could be useful in the differential diagnosis between follicular adenoma from follicular carcinoma.
Adenoma ; Carcinoma, Papillary ; Diagnosis, Differential ; Galectin 3 ; Paraffin ; Receptors, CXCR ; Receptors, CXCR4 ; Sensitivity and Specificity ; Thyroid Gland

PURPOSE: Experimental studies have suggested that the stromal-derived factor-1 (SDF-1)/CXCR4 axis is associated with tumor aggressiveness and metastasis in several malignancies. We performed a meta-analysis to elucidate the relationship between CXCR4 expression and the clinicopathological features of prostate cancer. MATERIALS AND METHODS: Data were collected from studies comparing Gleason score, T stage, and the presence of metastasis with CXCR4 levels in human prostate cancer samples. The studies were pooled, and the odds ratio (OR) of CXCR4 expression for clinical and pathological variables was calculated. RESULTS: Five articles were eligible for the current meta-analysis. We found no relationship between CXCR4 expression and Gleason score (<7 vs. > or =7). The forest plot using the fixed-effects model indicated an OR of 1.585 (95% confidence interval [CI]: 0.793~3.171; p=0.193). Further, CXCR4 expression was not associated with the T stage ( or =T3), and the relevant meta-analysis showed OR=1.803 (95% CI: 0.756~4.297, p=0.183). However, increased CXCR4 expression was strongly associated with metastatic disease with a fixed-effects pooled OR of 7.459 (95% CI: 2.665~20.878, p<0.001). CONCLUSIONS: Our meta-analysis showed that the higher CXCR4 protein expression in prostate cancer specimens is significantly associated with the presence of metastatic disease. This supports previous experimental data supporting the role played by the SDF-1/CXCR4 axis in metastasis.
Axis, Cervical Vertebra ; Humans ; Neoplasm Grading ; Neoplasm Metastasis* ; Odds Ratio ; Prostatic Neoplasms* ; Receptors, CXCR4

OBJECTIVE: To investigate the effect of chronic emotional stimulation induced by empty bottle stimulation on CXCL12/CXCR4-mediated inflammatory response in rats with acute myocardial infarction (AMI). METHODS: Rat models of anxiety were established by a 21-day stimulation with uncertain empty bottle drinking water, and myocardial infarction was induced by ligating the left anterior descending branch of the coronary artery; compound models were established by performing myocardial infarction operation on the 15th day of anxiety modeling. The rats were randomly divided into 4 groups: shamoperated group (=6), myocardial infarction group (=6), compound model group (with myocardial infarcted and anxiety; = 6), and inhibitor group (compound models treated daily with 1 mg/kg AMD3100 for 6 days; =7). Echocardiography was used to examine the LVEF and LVFS to evaluate the cardiac function of the rats. Elevated maze test and open field test were used to evaluate the behaviors of the rats. The expressions of CXCL12, CXCR4, IL-1β, IL-18 and neutrophil active protease (NE) in the myocardial tissues and blood samples were detected with ELISA and immunohistochemistry. RESULTS: The LVEF and LVFS were lower in the compound model group than in the sham group and myocardial infarction group ( < 0.05), and were higher in inhibitor group than in the compound model group ( < 0.05). LVID; d and LVID; s were lower in the inhibitor group than in the compound model group ( < 0.05). Compared to those in the sham group and myocardial infarction group, the rats in the compound model group more obviously preferred to stay in the closed arm ( < 0.05) in EPM; the rats in the inhibitor group had more times of entering and staying in the open arm than the compound model rats ( < 0.05); the horizontal and vertical movements were less in the compound model rats than in those in the sham group and the myocardial infarction group ( < 0.05) in OFT, and the vertical movement of the rats in inhibitor group was higher than those in the compound model group ( < 0.05). The expression of CXCR4 in the marginal zone of myocardial infarction was significantly higher in the compound model group than in the sham-operated group, myocardial infarction group and inhibitor group ( < 0.05). The expressions of IL-1β, IL-18 and NE in the inhibitor group were significantly lower than those in the compound model group ( < 0.05). Compared with at in the sham-operated group, the number of Nissl bodies in the compound model group decreased significantly ( < 0.01). CONCLUSIONS Chronic emotional stress induced by empty bottle stimulation can lead to dysfunction of the CXCL12/CXCR4 axis, which causes inflammatory cascade after myocardial infarction to worsen myocardial cell necrosis, cardiac function and hippocampal neuronal damage after the infarction.
Animals ; Chemokine CXCL12 ; Coronary Vessels ; Emotions ; Myocardial Infarction ; Myocardium ; Psychological Distress ; Rats ; Receptors, CXCR4 ; Signal Transduction

OBJECTIVE: To explore the effect of CXCR4 on the treatment response and prognosis of Carfilzomib (CFZ) in multiple myeloma. METHODS: Dataset GSE69078 based on microarray data from two CFZ-resistant MM cell lines and their corresponding parental cell lines (KMS11-KMS11/CFZ and KMS34-KMS34/CFZ) were downloaded from Gene Expression Omnibus (GEO). Differentially expressed genes (DEGs) were identified, and Protein-protein interaction (PPI) network was established to identify the key genes involved in CFZ resistance acquisition. Finally, the prognostic roles of the CFZ risistance key genes in MM using MMRF-CoMMpass data study was verified. RESULTS: 44 up-regulated and 46 down-regulated DEGs were identified. Top 10 hub genes (CCND1, CXCR4, HGF, PECAM1, ID1, HEY1, TCF4, HIST1H4J, HIST1H2BD and HIST1H2BH) were identified via Protein-protein interaction (PPI) network analysis. The CoMMpass data showed that high CXCR4 expression showed correlation to relative higher relapse and progress rates and the overall survival was significant decreased in high CXCR4 patients (P=0.013). CONCLUSION CXCR4 perhaps plays a crucial role in CFZ acquired resistance, which might help identifying potential CFZ-sensitive patients before treatment and providing a new therapeutic target in CFZ-resistant MM.
Histones ; Humans ; Multiple Myeloma/genetics* ; Neoplasm Recurrence, Local ; Oligopeptides/therapeutic use* ; Prognosis ; Receptors, CXCR4

Pulmonary fibrosis is an irreversible interstitial lung disease characterized by lung parenchyma remodeling and collagen deposition. In recent years, the incidence and mortality of pulmonary fibrosis caused by unknown causes have risen. However, its pathogenesis is still unclear. C-X-C motif chemokine ligand 12 (CXCL12)/C-X-C chemokine receptor 4 (CXCR4)/CXCR7 signal axis plays a critical regulatory role in pulmonary fibrosis disease. In addition, the signal axis has been shown to regulate recruitment and migration of circulating fibrocytes, mesenchymal stem cells to the damage lung tissue, the migration of endothelial cells, the proliferation and differentiation of fibroblasts and endothelial cells, which further affects the occurrence and progression of pulmonary fibrosis. In this review, we summarized the pathogenesis and treatment research progress of CXCL12 and its receptor CXCR4/CXCR7 in the occurrence and progression of pulmonary fibrosis.
Chemokine CXCL12 ; Endothelial Cells/pathology* ; Humans ; Ligands ; Lung/pathology* ; Pulmonary Fibrosis/pathology* ; Receptors, CXCR4

OBJECTIVE: To explore the improvement effect of CXC chemokine receptor 4 (Cxcr4) gene-modified bone marrow mesenchymal stem cell (BMSC)-derived exosomes on aplastic anemia (AA), and make a preliminary exploration of the mechanism. METHODS: Mouse BMSCs were isolated and cultured, then infected by recombinant lentivirus carrying Cxcr4 gene. The expression of green fluorescence was observed through fluorescence microscope, the expression of Cxcr4 mRNA was detected by real-time fluorescence quantitative PCR, and the BMSC-derived exosomes modified with Cxcr4 gene were extracted. Mouse models of AA were constructed, and control group, model group (AA), AA+BMSC group, AA+NC-BMSC group, AA+Cxcr4-BMSC group were set up. Except control group and model group, the other three groups of mice were injected 400 μl exosomes from different sources via the tail vein, after 2 weeks, the routine blood indices and the number of bone marrow nucleated cells were detected, the pathological changes of bone marrow were observed by HE staining, and the expression level of Treg cells was detected by flow cytometry. RESULTS: Mouse BMSCs were successfully isolated, and BMSCs with high expression of Cxcr4 and their exosomes were obtained. Compared with the control group, the number of red blood cell (RBC), white blood cell (WBC), and platelet (PLT), the hemoglobin (Hb) content and proportion of Treg cells in the peripheral blood of mice in the model group significantly decreased (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01). The proliferation level of nucleated cells was low, and the medullary cavity was filled with a large number of fat cells. Compared with the model group, the number of RBC, WBC, PLT, the Hb content and proportion of Treg cells in the peripheral blood of mice in the AA+BMSC group, AA+NC-BMSC group, and AA+Cxcr4-BMSC group significantly increased (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01), and pathological changes of bone marrow were improved. In addition, the number of RBC, WBC, PLT, the Hb content and proportion of Treg cells in the peripheral blood of mice in the AA+Cxcr4-BMSC group were significantly higher than those in the AA+BMSC group (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01). CONCLUSION Injection of Cxcr4 gene-modified BMSC-derived exosomes has a certain improvement effect on AA mice, and the mechanism may be related to an increase of the proportion of Treg cells.
Anemia, Aplastic/metabolism* ; Animals ; Bone Marrow Cells ; Exosomes/metabolism* ; Humans ; Mesenchymal Stem Cells ; Mice ; Receptors, CXCR4