Retraction: Knockdown of Urothelial Carcinoma-Associated 1 Suppressed Cell Growth and Migration Through Regulating miR-301a and CXCR4 in Osteosarcoma MHCC97 Cells

Following the publication,concerns have been raised about a number of figures in this article.The western blots in this article were presented with atypical,unusually shaped and possibly anomalous protein bands in many cases.The authors were contacted and invited to comment on the concerns raised and to provide the original,unmodified figures,but did not respond.The Editors-in-Chief therefore no longer have confidence in the integrity of the data in this article and decided to retract this article.

Crosstalk between androgen signaling and the chemokine receptor CXCR4:a novel strategy to promote myelin regeneration

Multiple sclerosis(MS)is the most common chronic disease of the central nervous system(CNS)in young adults and represents the first cause of severe handicap,originally non-traumatic(Oh et al.,2018).MS is chara cterized by the infiltration of auto reactive lymphocytes specific to myelin through the blood-brain barrier,which results in the appearance of inflammatory demyelinating lesions caused by the death of the central nervous system myelinating cells,oligodendrocytes(Oh et al.,2018).There is a prevalence sexual with a ratio of three times more affected women than men.

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological recovery.However,the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear.In this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 expression.However,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial activation.In agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice.Notably,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head injury.In conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry,thereby promoting induced neural stem cell–mediated improvement of neuronal injury,cerebral edema,and neurological disorders following closed head injury.

Targeting CXCR4 and EDN1 for the treatment of recurrent miscarriage using stearic acid from traditional Chinese medicine

Background:Recurrent miscarriage(RM)affects an estimated 1-3%of couples attempting to conceive,and its molecular components stay ineffectively caught on.This study aims to explore potential therapeutic targets for RM by examining gene expression patterns and biological pathways in both mouse and human RM models.Meanwhile,explore relevant traditional Chinese medicine(TCM)components targeting potential therapeutic targets.Methods:We utilized the GSE211251 mouse and the GSE26787 human datasets,employing gene set enrichment analysis and gene metaphysics analysis to examine differentially expressed genes and enriched pathways.Single-cell RNA analysis uncovered cellular heterogeneity and arranged pharmacology-mapped potential drug-target intelligence.We employed molecular docking strategies to assess the affinity of TCM components for key proteins.Results:In the mouse model,genes such as Ly6f1 and Gpr26 were upregulated,while Stc5a and Galca exhibited downregulation.Gene set enrichment analysis identified key pathways,including the tumor necrosis factor-mediated signaling pathway.In human samples,Gene Ontology analysis highlighted processes such as apoptosis and cell adhesion.Single-cell RNA analysis revealed distinct cellular populations between normal and RM samples.Systems pharmacology identified C-X-C motif chemokine receptor 4(CXCR4)and endothelin 1(EDN1)as potential key targets,and molecular docking confirmed that stearic acid from TCM appears to regulate these proteins.Conclusion:This study presents a comprehensive analysis of the genetic and cellular underpinnings of RM,identifying CXCR4 and EDN1 as promising therapeutic targets.Stearic acid from TCM could provide targeted treatment by modulating these key proteins,paving the way for new RM treatment strategies.

RhoC、CXCR4基因与宫颈癌生物学行为的关系

目的:探讨宫颈癌和正常宫颈组织中RhoC、CXCR4 mRNA的表达及意义。方法:采用逆转录多聚酶链反应(RT-PCR)技术分析宫颈癌(36例)和正常宫颈组织(30例)中RhoC、CXCR4 mRNA的表达。结果:RhoC、CX-CR4 mRNA在宫颈癌中表达增高,其表达与宫颈癌的临床分期、淋巴结转移有关,而与癌细胞分化程度无关。结论:RhoC、CXCR4基因的过量表达与宫颈癌的发生发展和转移密切相关。

子宫内膜癌组织中趋化因子CXCL12及其受体 CXCR4表达水平研究

目的：观察子宫内膜癌组织中趋化因子 CXCL12及其受体 CXCR4表达水平，探讨其与子宫内膜癌患者临床病理特征相关性。方法收集2012年1月～2014年12月间入院接受手术的子宫内膜癌患者52例病理标本，年龄55.6±19.2岁，以正常子宫内膜26例为对照组，年龄52.3±16.5岁。采用免疫组化技术检测趋化因子 CXCL12及其受体 CX-CR4在子宫内膜癌组织中的表达情况，并分析它们与 FIGO 分期、细胞分化程度、淋巴结转移和病理类型等临床病理特征的关系。结果CXCL12和 CXCR4在子宫内膜癌组织中阳性表达率分别为76.92％和69.23％，而在正常子宫内膜组织中则分别为34.62％和30.77％，差异具有统计学意义（χ2＝11.826，P ＜0.01）。CXCR4的表达与子宫内膜癌细胞分化程度存在差异，有统计学意义（均 P ＜0.05），且与分化高低呈正相关（r＝0.386，P ＜0.05）。在子宫内膜癌组织中，除 CXCR4表达与细胞分化程度呈正相关外，CXCL12和 CXCR4表达与临床分期、淋巴结转移和病理类型无相关性（P ＞0.05）。结论CXCL12和 CXCR4在子宫内膜癌组织中表达明显升高，这可能在子宫内膜癌发生发展过程中发挥重要生物学作用。

Transfusion of CXCR4-priming endothelial progenitor cells reduces cerebral ischemic damage and promotes angiogenesis and neurogenesis in db/db diabetic mice

Previous studies suggest that reduction and dysfunction of circulating endothelial progenitor cells(EPCs),and dysregulation in stromal cell derived factor-1/CXC-chemokine receptor 4(SDF-1/ CXCR4) axis in diabetes could be therapeutic targets for diabetic ischemic stroke.This study investigated the efficacy of CXCR4-priming EPCs on cerebral repair following ischemic stroke in db/db diabetic mice.Bone marrow derived EPCs from db/+ control mice were transfected with adenovirus(1×10~7 IU) carrying CXCR4(Ad-CXCR4-EPCs)or null(Ad- null-EPCs).The db/db mice were divided into three groups for EPCs injection(2×10~5 cells/100μl): Ad-CXCR4-EPCs,Ad-null-EPCs or saline(vehicle), via tail vein 2 hrs after middle cerebral artery occlusion (MCAO) surgery.Cerebral blood flow(CBF) was measured with laser Doppler flowmeter.Mice were sacrificed at 2 or 7 days thereafter.Level of circulating EPCs was measured by flow cytometry. Ischemic damage,cerebral microvascular density (MVD),angiogenesis and neurogenesis were determined by histological staining with Fluoro-J,CD31, CD31 +BrdU,NeuN +BrdU,GFAP+BrdU,respectively. Results(table) showed:1) Levels of CXCR4 expression were reduced in the brain and EPCs of db/db mice as measured by real-time RT-PCR and western blot analyses(data not shown);2) The level of circulating EPCs was more in the mice treated with Ad-CXCR4-EPCs;3)EPC transfusion improved CBF,increased MVD,angiogenesis and neurogenesis in peri-infarct area,and decreased ischemic damage.The efficacies were better in Ad-CXCR4 -EPCs group.Data suggest that transfusion of Ad-CXCR4-EPCs could be a therapeutic avenue for ischemia stroke in diabetes.

Inhibition of CXCR4 activity with AMD3100 decreases invasion of human colorectal cancer cells in vitro

AIM: To investigate the effect and mechanism of blockade of the CXC chemokine receptor-4 (CXCR4) signaling pathway by AMD3100, a small non-peptide CXCR4 inhibitor, on invasion and metastasis of colorectal cancer cells in vitro. METHODS: Human colorectal cancer cell line SW480 was treated with AMD3100 at different final concentrations. 3-(4,5-dimethylthiazole-2-yl)-2.5-dipheny-ltetrazolium bromide (MTT) assay was used to detect the effect of AMD3100 on cell proliferation. The invasion ability of SW480 cells was determined by cell invasion assay kit. In the presence of AMD3100, the CXCL12-mediated migratory response of SW480 cells was tested by classical chemotaxis assays. RT-PCR analysis and Western blotting were used to detect the expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) in SW480 cells. RESULTS: Cell viability was significantly suppressed by AMD3100 in a dose-dependent manner. AMD3100 (100 and 1000 ng/mL) significantly inhibited the invasion ability of SW480 cells. Treatment with AMD3100 markedly reduced the expression of VEGF and MMP-9 but not MMP-2 in SW480 cells. CONCLUSION: The CXCL12/CXCR4 system is an important mediator of proliferation and invasion of CXCR4-expressing colorectal cancer cells. AMD3100 inhibited invasion and metastasis activity of the colorectalcancer cell line SW480 through down-regulation of VEGF and MMP-9 expression.

Effects of Triptolide on Cell Proliferation and CXCR4 Expression in Burkitt’s Lymphoma Raji Cells In Vitro

Objective： To investigate the inhibitory effects of triptolide on cell proliferation and CXCR4 expression in Burkitt＇s lymphoma cell line Raji cells. Methods： The effects of triptolide on the growth of Raji cells were studied by 3-（4, 5-Dimethyl-2-thiazolyl）-2, 5-diphenyl-2H-tetrazolium（MTT） assay. The effects of triptolide on CXCR4 expression on Raji cells were studied by flow cytometric analysis. Chemotaxis assays were performed to observe the effects of triptolide on migration of Raji cells towards recombinant human SDF-1α （rhSDF-1α） in vitro. Results： Triptolide inhibited the proliferation of Raji cells in a dose- and time-dependent way with a 24-h IC50 value of 43.06 nmol/L and a 36-h IC50 value of 25.08 nmol/L. Triptolide could downregulate the CXCR4 expression on Raji cells in a dose-dependent manner. Furthermore, chemotaxis assays showed that triptolide could block the migration of Raji cells to rhSDF-1α in vitro, and the inhibition was dose-dependent. Conclusion： Triptolide could inhibit the proliferation and migration of Raji cells in vitro. The underlying anti-tumor mechanism of triptolide might be related to the anti-proliferative effect and the blockage of SDF-1/CXCR4 axis.

Study on the Expression Levels of CXCR4, CXCL12, CD44, and CD147 and Their Potential Correlation with Invasive Behaviors of Pituitary Adenomas

Objective To evaluate the factors of CXCR4, CXCL12, CD44, and CD147 as early potential diagnostic biomarkers by determining their expression levels in invasive and non-invasive pituitary adenomas. Methods Fresh pituitary adenoma specimens were collected from 35 pituitary adenoma （21 invasive and 14 non-invasive） patients who underwent surgical treatment in our Neurosurgery Department between January and April of 2009. The expression levels of CXCR4, CXCL12, CD44, and CD147 were evaluated firstly by flow cytometry, fluorescence microscopy in single cell suspensions, and then by immunohistochemical staining of paraffin tissue sections. Results Flow cytometric analyses showed that the percentage of CXCR4- and CXCL12-positive cells from invasive pituitary adenomas （IPA） was significantly higher in the single cell suspensions than that from non-invasive pituitary adenomas （nlPA） （P〈O.05）. Immunohistochemical staining revealed that CXCR4 and CXCL12 staining index scores of the invasive pituitary adenomas were significantly higher than those of the non-invasive pituitary adenomas （P〈O.05）. In contrast, neither flow cytometry nor immunohistochemical staining demonstrated significant difference between CD44 and CD147 expression levels, respectively. Conclusion Expression levels of CXCR4 and CXCL12 are correlated with the invasiveness of pituitary adenomas. Therefore, rather than CD44 and CD147, CXCR4 and CXCL12 may potentially serve as biomarkers for early detection of pituitary adenomas.

Influence of CXCR4/SDF-1 axis on E-cadherin/β-catenin complex expression in HT29 colon cancer cells

AIM： To study the influence of CXCR4/stromal cell- derived factor-1 （SDF-1） axis on E-cadherin/β-catenin complex expression in HT29 colon cancer ceils and its underlying mechanisms. METHODS： Effect of SDF-1 on E-cadherin/β-catenin expression was detected by immunocytochemistry. E-cadherin and/3-catenin mRNA expression levels were measured by reverse transcriptase-polymerase chain reaction. SDF-l-induced phosphorylation of phosphati- dylinositol 3-kinase （PI3K）/AKT and β-catenin was detected by Western blotting. RESULTS： The E-cadherin and β-catenin mRNA ex-pression levels in HT29 cells were lower 48 h after incubated with SDF-1 at the concentrations of 20 and 40 ng/mL （P 〈 0.05）. SDF-l-induced significant phosphorylation of PI3K/AKT and β-catenin. AMD3100 and LY294002 inhibited the phosphorylation of PI3K/AKT and β-catenin. CONCLUSION： SDF-1 down-regulates the E-cadherin/ β-catenin complex expression in HT29 cells by decreasing mRNA synthesis and increasing β-catenin phosphorylation.

Comparison of skeletal and soft tissue pericytes identifies CXCR4+ bone forming mural cells in human tissues

Human osteogenic progenitors are not precisely defined,being primarily studied as heterogeneous multipotent cell populations and termed mesenchymal stem cells(MSCs).Notably,select human pericytes can develop into bone-forming osteoblasts.Here,we sought to define the differentiation potential of CD146 f human pericytes from skeletal and soft tissue sources,with the underlying goal of defining cell surface markers that typify an osteoblastogenic pericyte.CD146+CD31~CD45_pericytes were derived by fluorescence-activated cell sorting from human periosteum,adipose,or dermal tissue.Periosteal CD146+CD31—CD45 cells retained canonical features of pericytes/MSC.Periosteal pericytes demonstrated a striking tendency to undergo osteoblastogenesis in vitro and skeletogenesis in vivo,while soft tissue pericytes did not readily.Transcriptome analysis revealed higher CXCR4 signaling among periosteal pericytes in comparison to their soft tissue counterparts,and CXCR4 chemical inhibition abrogated ectopic ossification by periosteal pericytes.Conversely,enrichment of CXCR4+pericytes or stromal cells identified an osteoblastic/non-adipocytic precursor cell.In sum,human skeletal and soft tissue pericytes differ in their basal abilities to form bone.Diversity exists in soft tissue pericytes,however,and CXCR4+pericytes represent an osteoblastogenic,non-adipocytic cell precursor.Indeed,enrichment for CXCR4-expressing stromal cells is a potential new tactic for skeletal tissue engineering.

Nef-M1, a CXCR4 Peptide Antagonist, Enhances Apoptosis and Inhibits Primary Tumor Growth and Metastasis in Breast Cancer

Results from studies with animal models suggest that, in many cancers, CXCR4 is an important therapeutic target and that CXCR4 antagonists may be promising treatments for primary cancers and for metastases. The Nef protein effectively competes with CXCR4’s natural ligand, SDF-1α, and induces apoptosis. As described in this report, the Nef-M1 peptide (Nef protein amino acids 50 - 60) inhibits primary tumor growth and metastasis of breast cancer (BC). Four BC cell lines (MDA-MB-231, MDA-MB-468, MCF 7, and DU4475) and primary human mammary epithelium (HME) cells were evaluated for their response to the Nef protein and to the Nef-M1 peptide. The presence of CXCR4 receptors in these cells was determined by RT-PCR, Western blot (WB), and immunohistochemical analyses. The apoptotic effect of Nef-M1 was assessed by terminal transferase dUTP nick-end labeling (TUNEL). WBs was used to assess caspase 3 activation. BC xenografts grown in SCID mice were evaluated for the presence of CXCR4 and for their metastatic potential. CXCR4 was presented in MDA-MB-231, MCF 7, and DU 4475 BC cells but not in MDA-MB-468 BC or HME cells. Cells expressing CXCR4 and treated with Nef-M1 peptide or the Nef protein had higher rates of apoptosis than untreated cells. Caspase-3 activation increased in MDA-MB 231 cells treated with the Nef protein, the Nef 41 - 60 peptide, or Nef-M1. Nef-M1, administered to mice starting at the time of xenograft implantation, inhibited growth of primary tumors and metastatic spread. Untreated mice developed diffuse intraperitoneal metastases. We conclude that, in BCs, Nef-M1, through interaction with CXCR4, inhibits primary tumor growth and metastasis by causing apoptosis.

Retrovirus-Mediated CXCR4-siRNA Can Inhibit the Invasion of Prostate Carcinoma In Vitro

Objective： CXCR4 is a potential target for cancer gene therapy. In this study, an RNA interference retrovirus vector targeting CXCR4 gene was constructed, and its influence on the invasion of prostate cancer cells by depressing CXCR4 gene expression was analyzed. Methods： the CXCR4-specific siRNA gene was cloned by PCR and inserted into the Pgensil-1 plasmid eonstaining U6 promoter and EGFP, and then the recombinant fragment was sub-cloned into PLXSN and tested by restriction enzyme and sequencing. The virus obtained from transfected PA317 cells was transfected into prostate cancer cells. The expression of CXCR4 mRNA was detected by RT-PCR. The ability of invasion of prostate cancer cells in vitro was estimated by Transwell experiment. Results： it was showed that with the recombinant PLXSN transfection, the expression of CXCR4 mRNA in prostate cancer cells PC-3m and LNCaP was reduced at rates of （84.26±10.20）% and （88.17±11.23）%, respectively. The results of Transwell experiment also showed that the number of cells under micro-membrane were 14.7±3.1 and 18.9±4.2 in the treated group of PC-3m and LNCaP, respectively, compared with 46.9±5.3 and 66.7±6.0 in the control group （P〈0.05）. Conclusion： PLXSN/EGFP-U6-siCXCR4 can significantly depress the expression f CXCR4, by which the invasiveness of prostate cancer cells in vitro was inhibited as well. This recombinant fragment would be helpful in the treatment of prostate cancer.

Effect of CXCR4 pretreated with ultrasound-exposed microbubbles on accelerating homing of bone marrow mesenchymal stem cells to ischemic myocardium in AMI rats

Objective: To investigate the role and potential mechanism of CXCR4 in promoting targeted homing of bone marrow mesenchymal stem cells(BMSCs) with ultrasound-exposed microbubbles(UM) pretreatment. Methods: Third generation BMSCs were divided into four groups control group, ultrasound(US) group, UM group and ultrasound-exposed microbubbles plus catalase group. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and protein expression, respectively. Third generation BMSCs were labeled with Fluo-α/AM and divided into three groups: control group, US group and UM group, and flurorescence intensities in the cells were observed immediately, 5 min and 15 min after intervention underflurorescence microscope. The calcium iron levels in the cells were analyzed. BMSCs were divided into i ve group: group A without calcium in the medium, group B, group C, group D and group E containing calcium chloride with concentration of l mol, 2 mol, 4mol, anti-calciurn-sensing receptor antibody, respectively. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and proteins expression of the third generation BMSCs of each group, respectively. Results: The levels of CXCR4 m RNA transcription and protein expression between US group and control group had no statistically signii cant dif erence(P>0.05) shown by RT-PCR and western blot; the transcription level in the UM group was signii cantly higher than that in US group and control group(P<0.05); and in the ultrasound-exposed microbubbles plus catalase group, the transcription level was much lower than that in UM group. Fluorescence intensify in the cells of US group had no signii cant dif erence compared with that in the cells of the control group(P>0.05), which in the cells of UM group was signii cantly higher than that in the cells of both US group and control group(P<0.05). Compared to group A, expressions of CXCR4 of group B to D were signii cantly increased in concentration-dependent manner showed by RT-PCR and western blot(P< 0.05). Compared to group C, expressions of CXCR4 of group E were signii cantly decreased(P< 0.05). Conclusions: UM can promote the inl ux of calcium in BMSCs and increase m RNA transcription and protein expression of CXCR4. The latter may partly be caused by influx of calcium.

Expression levels of CXCR4 and VEGF correlate with blood-borne metastatic progression and outcome in patients with osteosarcoma

Objective:We determine whether chemokine receptor CXCR4 and vascular endothelial growth factor(VEGF) expression related to the metastasis and survival outcome of patients with osteosarcoma.Methods:Tissue microarray(TMA) was used to detect the expression of CXCR4 and VEGF in 56 osteosarcoma patient samples.Two-year follow-up was performed to observe the metastatic behavior and overall survival of osteosarcoma patients.Results:There was a significant correlation between the expression levels of CXCR4 and VEGF in 56 osteosarcoma patient samples(P = 0.002).Univariate analysis revealed the expression of CXCR4 and VEGF was not associated with age, gender and the level of ALP but associated with clinical stage.Conclusion:These data raises the possibility that VEGF could regulate the levels of CXCR4 to promote the migration of tumor cells to target organs.CXCR4 and VEGF expression are highly correlated with metastatic progression in patients with osteosarcoma and their immunohistochemical expression have predictive value for the metastatic development.

CXCL12 Retargeting of an Oncolytic Adenovirus Vector to the Chemokine CXCR4 and CXCR7 Receptors in Breast Cancer

Breast cancer is the most frequently diagnosed cancer in women under 60, and the second most diagnosed cancer in women over 60. While significant progress has been made in developing targeted therapies for breast cancer, advanced breast cancer continues to have high mortality, with poor 5-year survival rates. Thus, current therapies are insufficient in treating advanced stages of breast cancer;new treatments are sorely needed to address the complexity of advanced-stage breast cancer. Oncolytic virotherapy has been explored as a therapeutic approach capable of systemic administration, targeting cancer cells, and sparing normal tissue. In particular, oncolytic adenoviruses have been exploited as viral vectors due to their ease of manipulation, production, and demonstrated clinical safety profile. In this study, we engineered an oncolytic adenovirus to target the chemokine receptors CXCR4 and CXCR7. The overexpression of CXCR4 and CXCR7 is implicated in the initiation, survival, progress, and metastasis of breast cancer. Both receptors bind to the ligand, CXCL12 (SDF-1), which has been identified to play a crucial role in the metastasis of breast cancer cells. This study incorporated a T4 fibritin protein fused to CXCL12 into the tail domain of an adenovirus fiber to retarget the vector to the CXCR4 and CXCR7 chemokine receptors. We showed that the modified virus targets and infects CXCR4- and CXCR7-overexpressing breast cancer cells more efficiently than a wild-type control vector. In addition, the substitution of the wild-type fiber and knob with the modified chimeric fiber did not interfere with oncolytic capability. Overall, the results of this study demonstrate the feasibility of retargeting adenovirus vectors to chemokine receptor-positive tumors.

Clinicopathologic significance of CXCR4 and Nrf2 in colorectal cancer

The CXCR4 and Nrf2 signaling pathways are abnormally activated in response to cellular stress in various types of human cancers. In this study, we examined the expression of CXCR4 and Nrf2 in colorectal cancer （CRC） tissue specimens and investigated their correlation with patient clinicopathologic characteristics. We determined CXCR4 and Nrf2 expression in 76 CRC tissue specimens and paired normal tissue specimens by immunohistochemistry and real-time PCR. We found that the protein and mRNA transcript levels of CXCR4 were significantly higher in CRC tissue specimens than in paired normal tissues, while the expressions of Nrf2 protein and mRNA were increased in CRC tissues compared to distant non-cancerous tissues. High expression level of CXCR4 was positively correlated with poorly differentiated （P=0.031）, more advanced tumor-node-metastasis （TNM） stage （P=0.019）, lymph node metastasis （P=0.007） and distant metastasis （P=0.018）. However, the expression of Nrf2 protein was positively correlated with larger tumor size （P=0.049）, more advanced TNM stage （P=0.013）, lymph node metastasis （P=0.016） and distant metastasis （P=0.023）. Moreover, there was a strong relationship between CXCR4 and Nrf2 expression in CRC tissues, indicating that high Nrf2 expression may contribute to CXCR4 overexpression. In addition, combined expression of CXCR4 and Nrf2 strongly correlated with lymph node metastasis and distant metastasis （P=0.003）. Furthermore, we found that combined high expression of CXCR4 and Nrf2 had stronger correlation with lymph node metastasis and distant metastasis than any single molecule did. This study indicated that the abnormal expression of CXCR4 and Nrf2 contributed to the progression of CRC.

A549/DDP derived exosomes can affect cisplatin chemosensitivity via transporting CXCR4 to A549 cells

The resistance of cancer cells to the anti-cancer drugs is the most important reason that affecting the efficacy of the non-small cell lung cancer(NSCLC)chemotherapy;thus,to explore the underlyingmechanismof drug resistance ofNSCLC medications is urgently needed for improving the therapeutic efficacy of current anti-NSCLC chemotherapies.The aim of the present study is to explore the roles of exosomes in the chemosensitivity of A549 cells and the related mechanism.A549 cells and cisplatin resistant cell line A549/DDP derived exosomes were isolated,and the expressions of CXCR4 were compared.Then,after cisplatin treatment,A549 cells were treated with exosomes,and the proliferation,apoptosis,migration,and invasion of the cells were examined.Finally,the tumorigenic effect of A549/DDP derived exosomes were also evaluated by cisplatin treated xenograft tumor mice models in vivo.We found that A549/DDP derived exosomes increased the proliferation,migration,and invasion,and inhibited the apoptosis and cisplatin sensitivity of A549 cells.CXCR4 was also significantly increased in cells treated with A549/DDP derived exosomes.Furthermore,A549/DDP derived exosomes may also decrease the chemosensitivity of NSCLC cells to cisplatin in vivo.Our data suggested that A549/DDP derived exosomes can affect the chemosensitivity of A549 cells to cisplatin,possibly by transporting CXCR4 to A549 cells.Our data may provide novel evidence for the investigation of drug resistance of NSCLC.

Effect of Lentivirus-induced shRNA Silencing CXCR4 Gene on Proliferation and Apoptosis in Human Esophageal Carcinoma Cell Line Eca109

OBJECTIVE To discuss the application of the slow virus-induced short-hairpin RNA （vshRNA） to silence the expression of CXCR4 in EsCa cell lines Eca109, and observe the effect of silencing CXCR4 on the proliferation and apoptosis of Eca109 cells in vitro. METHODS The expression plasmid of vshRNA targeting CXCR4 was constructed, with a concurrent construction of negative vshRNA expression plasmid, and without targeting any known mRNA. Real-time quantitative PCR and Western blot assay were used to determine the change of CXCR4 expression in the post-transfected EsCa cell Eca109, and MTT assay was conducted to detect the change of proliferation in EsCa Eca109 cell after silencing the CXCR4. The .ow cytometry was used to detect the change of the cell cycle and apoptosis in the post-silenced EsCa Eca109 cell in di. erent groups. RESULTS The transfection rate was respectively （87.3 ± 1.2）% and （90.1 ± 1.4）% in the CXCR4- RNAi-LV （silent group） and NC-GFP-RNAi-LV （negative control group） cellular plasmids. The vshRNA interference resulted in a down-regulation of the CXCR4 gene mRNA and protein expressions in Eca109 cells. CXCL12 promoted the proliferation of EsCa cell lines Eca109. The speed of EsCa cell proliferation became slower in the silencing group than in the normal control （also the control） and the negative control groups （P 〈 0.05）. However, there was no significant difference in comparison of the proliferation speeds between the negative control and the normal control groups （P 〉 0.05）. In the silencing group, the proportion of the cells in phase G0/G1, phase S and phase G2/M was respectively （69.9 ± 5.0）%, （17.1 ± 2.5）% and （13.0 ± 7.4）%, and the apoptotic rate achieved （7.27 ± 0.50）%. In the normal control group, the proportion of the cells in phase G0/G1, S and G2/M was respectively （55.9 ± 4.6）%, （30.2 ± 3.9）% and （13.8 ± 1.4）%, and the apoptotic rate was （3.30 ± 0.70）%. In the negative control group, the proportion of cells in phase G0/G1, S and G2/M was respectively （52.7 ± 7.8）%, （25.3 ± 2.3）% and （21.9 ± 7.4）%, with an apoptotic rate of （4.03 ± 1.37）%. Compared with the normal control and negative control groups, there was an apparent growth of cells in the phase G0/G1 （P 〈 0.05）, and a greatly increased number of cells in phase S （P 〈 0.05） in the silencing group. There was no signi. cant di.erence in comparison of those between the normal control and negative control groups （P 〉 0.05）. The apoptotic rate was obviously higher in the cells of the silencing group than in the normal control and the negative control groups （P 〈 0.05）. There was no signi. cant di.erence in comparison of the apoptotic rate between the normal control and the negative control groups （P 〉 0.05）. CONCLUSION CXCR4-vshRNA can specifically and effectively inhibit CXCR4 expression of Eca109 cells. CXCR4-vshRNA can inhibit the proliferation and enhance the apoptosis rate of Eca109 cells through intervening the expression of CXCR4, suggesting that CXCL12/CXCR4 might have an important role in the progression of Escc Thisslow virus-induced shRNA can effectively silence the expression of CXCR4 gene in the EsCa cells; block up the biological e.ect of CXCL12/CXCR4 axle; and e.ectively inhibit the potency of proliferation in the EsCa cell line Eca109, thus advancing apoptosis. It suggests that the CXCL12/CXCR4 plays an important role in the progression of EsCa.