CXCR7 signaling induced epithelial-mesenchymal transition by AKT and ERK pathways in epithelial ovarian carcinomas

Personalization of Therapy in High-Grade Serous Tubo-Ovarian Cancer-The Possibility or the Necessity?

High-grade serous tubo-ovarian cancer (HGSTOC) is the most lethal tumor of the female genital tract. The foregoing therapy consists of cytoreduction followed by standard platinum/taxane chemotherapy; alternatively, for primary unresectable tumors, neo-adjuvant platinum/taxane chemotherapy followed by delayed interval cytoreduction. In patients with suboptimal surgery or advanced disease, different forms of targeted therapy have been accepted or tested in clinical trials. Studies on HGSTOC discovered its genetic and proteomic heterogeneity, epigenetic regulation, and the role of the tumor microenvironment. These findings turned attention to the fact that there are several distinct primary tumor subtypes of HGSTOC and the unique biology of primary, metastatic, and recurrent tumors may result in a differential drug response. This results in both chemo-refractoriness of some primary tumors and, what is significantly more frequent and destructive, secondary chemo-resistance of metastatic and recurrent HGSTOC tumors. Treatment possibilities for platinum-resistant disease include several chemotherapeutics with moderate activity and different targeted drugs with difficult tolerable effects. Therefore, the question appears as to why different subtypes of ovarian cancer are predominantly treated based on the same therapeutic schemes and not in an individualized way, adjusted to the biology of a specific tumor subtype and temporal moment of the disease. The paper reviews the genomic, mutational, and epigenetic signatures of HGSTOC subtypes and the tumor microenvironment. The clinical trials on personalized therapy and the overall results of a new, comprehensive approach to personalized therapy for ovarian cancer have been presented and discussed.

Tenofovir alone or combined with doxorubicin abrogates DMBA-induced mammary cell carcinoma: An insight into its modulatory impact on oxidative/Notch/apoptotic signaling

AIMS

Breast cancer incidence keeps on growing and emerging as one of the major global challenges, therefore, the introduction of new approaches is of great demand. Drug repurposing is crucial to faster and cheaper discovery of anti-cancer drugs. The antiviral tenofovir disproxil fumarate (TF) was reported to decrease hepatocellular carcinoma risk by interfering with cell cycle and proliferation. This study aimed to scrutinize the role of TF alone or combined with doxorubicin (DOX) in 7,12-dimethylbenz (a) anthracene (DMBA)-induced breast carcinoma rat model.

MATERIALS AND METHODS

Breast carcinoma was induced by DMBA (7.5 mg/kg, twice/week, SC into mammary gland) for 4 successive weeks. TF (25 and 50 mg/kg/day) was given orally and DOX (2 mg/kg) was injected once/week by tail vein starting from day 1.

KEY FINDINGS

The anti-cancerous effect of TF was mediated by suppression of oxidative stress markers and Notch signaling proteins (Notch1, JAG1, and HES1), attenuation of tumor proliferation markers (cyclin-D1 and Ki67), and boosting of apoptosis (P53 and Caspase3) and autophagy biomarkers (Beclin1 and LC3). In parallel, histopathological assessment displayed that mammary glands from animals treated with TF alone or combined with DOX showed better histopathological scores. Interestingly, TF and DOX co-treatment markedly decreased myocardial injury markers (AST, LDH, and CK-MB), restored the balance between GSH and ROS, prohibited lipid peroxidation, and preserved microscopic myocardial architecture.

SIGNIFICANCE

TF elicited antitumor activity via multiple molecular mechanisms. Moreover, combining TF with DOX might be a potential novel strategy to enhance DOX-anticancer activity and decrease its cardiac side effects.

Molecular cluster mining of high-grade serous ovarian cancer via multi-omics data analysis aids precise medicine

PURPOSE

HGSOC is a kind of gynecological cancer with high mortality and strong heterogeneity. The study used multi-omics and multiple algorithms to identify novel molecular subtypes, which can help patients obtain more personalized treatments.

METHODS

Firstly, the consensus clustering result was obtained using a consensus ensemble of ten classical clustering algorithms, based on mRNA, lncRNA, DNA methylation, and mutation data. The difference in signaling pathways was evaluated using the single-sample gene set enrichment analysis (ssGSEA). Meanwhile, the relationship between genetic alteration, response to immunotherapy, drug sensitivity, prognosis, and subtypes was further analyzed. Finally, the reliability of the new subtype was verified in three external datasets.

RESULTS

Three molecular subtypes were identified. Immune desert subtype (CS1) had little enrichment in the immune microenvironment and metabolic pathways. Immune/non-stromal subtype (CS2) was enriched in the immune microenvironment and metabolism of polyamines. Immune/stromal subtype (CS3) not only enriched anti-tumor immune microenvironment characteristics but also enriched pro-tumor stroma characteristics, glycosaminoglycan metabolism, and sphingolipid metabolism. The CS2 had the best overall survival and the highest response rate to immunotherapy. The CS3 had the worst prognosis and the lowest response rate to immunotherapy but was more sensitive to PARP and VEGFR molecular-targeted therapy. The similar differences among three subtypes were successfully validated in three external cohorts.

CONCLUSION

We used ten clustering algorithms to comprehensively analyze four types of omics data, identified three biologically significant subtypes of HGSOC patients, and provided personalized treatment recommendations for each subtype. Our findings provided novel views into the HGSOC subtypes and could provide potential clinical treatment strategies.

The Role of Cytokines in Epithelial-Mesenchymal Transition in Gynaecological Cancers: A Systematic Review

Chronic inflammation has been closely linked to the development and progression of various cancers. The epithelial-mesenchymal transition (EMT) is a process involving the acquisition of mesenchymal features by carcinoma cells and is an important link between inflammation and cancer development. Inflammatory mediators in the tumour micro-environment, such as cytokines and chemokines, can promote EMT changes in cancer cells. The aim of this systematic review is to analyse the effect of cytokines on EMT in gynaecological cancers and discuss their possible therapeutic implications. A search of the databases CINAHL, Cochrane, Embase, Medline, PubMed, TRIP, and Web of Science was performed using the keywords: "cytokines" AND "epithelial mesenchymal transition OR transformation" AND "gynaecological cancer". Seventy-one articles reported that various cytokines, such as TGF-β, TNF-α, IL-6, etc., promoted EMT changes in ovarian, cervical, and endometrial cancers. The EMT changes included from epithelial to mesenchymal morphological change, downregulation of the epithelial markers E-cadherin/β-catenin, upregulation of the mesenchymal markers N-cadherin/vimentin/fibronectin, and upregulation of the EMT-transformation factors (EMT-TF) SNAI1/SNAI2/TWIST/ZEB. Cytokine-induced EMT can lead to gynaecological cancer development and metastasis and hence novel therapies targeting the cytokines or their EMT signalling pathways could possibly prevent cancer progression, reduce cancer recurrence, and prevent drug-resistance.

In Vitro Models of Ovarian Cancer: Bridging the Gap between Pathophysiology and Mechanistic Models

Ovarian cancer (OC) is a disease of major concern with a survival rate of about 40% at five years. This is attributed to the lack of visible and reliable symptoms during the onset of the disease, which leads over 80% of patients to be diagnosed at advanced stages. This implies that metastatic activity has advanced to the peritoneal cavity. It is associated with both genetic and phenotypic heterogeneity, which considerably increase the risks of relapse and reduce the survival rate. To understand ovarian cancer pathophysiology and strengthen the ability for drug screening, further development of relevant in vitro models that recapitulate the complexity of OC microenvironment and dynamics of OC cell population is required. In this line, the recent advances of tridimensional (3D) cell culture and microfluidics have allowed the development of highly innovative models that could bridge the gap between pathophysiology and mechanistic models for clinical research. This review first describes the pathophysiology of OC before detailing the engineering strategies developed to recapitulate those main biological features.

Determination of Potential Therapeutic Targets and Prognostic Markers of Ovarian Cancer by Bioinformatics Analysis

This study is to study the expression of CXCRs in ovarian cancer tissues and their value in prognosis. The expressions of CXCR1-CXCR7 mRNA between ovarian tumor tissues and normal tissues and in different pathological types of ovarian tumor tissues were compared by ONCOMINE online tool. The relationship between the expression of CXCRs and clinical pathological staging was studied by GEPIA. Kaplan-Meier plotter online tool was used to analyze prognosis. Finally, GO and KEGG analyses and protein interaction network analysis were performed for CXCRs by the DAVID software to predict their function, and cBioPortal was used to identify the key functional genes. The expression of CXCR3/4/7 mRNA in ovarian cancer tissues was higher than that in normal ovarian tissues, and the expression of CXCR4 was the highest (fold change = 306.413, P < 0.05). The expression of CXCR1/2/3/4/7 mRNA in different pathological types of ovarian tumors was significantly different (P < 0.05). Only CXCR5 expression level was associated with tumor staging. Survival analysis showed that high CXCR7 mRNA expression and low CXCR5/6 expression were associated with the shortening of overall survival. High CXCR4/7 expression and low CXCR5/6 expression were associated with the shortening of progression-free survival. High CXCR2/4 expression and low CXCR5/6 expression were closely related to the shortening of postprogressing survival. Protein interaction network analysis showed that GNB1, PTK2, MAPK1, PIK3CA, GNB4, GNA11, KNG1, and ARNT proteins were closely related to the CXC receptor family. CXCR3/4/7 are potential therapeutic targets, and CXCR2/4/5/6/7 are new markers for the prognosis of ovarian cancer.

Impact of Selected Signaling Proteins on SNAIL 1 and SNAIL 2 Expression in Ovarian Cancer Cell Lines in Relation to Cells' Cisplatin Resistance and EMT Markers Level

It has been increasingly recognized that SNAIL1 and SNAIL2, as major EMT-inducers, might also be involved in drug resistance of cancer cells. We sought to determine a relation between SNAIL1/2, E-cadherin and N-cadherin expression, as well as ovarian cancer cells’ resistance to cisplatin and EMT markers’ level. Thus, four ovarian cancer cell lines, were used: A2780, A2780cis, SK-OV-3 and OVCAR-3. We assessed the impact of ERK1/2, AKT and STAT3 proteins (chosen by the profiling activity of over 40 signaling proteins) on SNAIL1/2 expression, along with E-cadherin and N-cadherin levels. We showed that expression of SNAIL1 and N-cadherin are the highest in cisplatin-resistant A2780cis and SK-OV-3 cells, while high SNAIL2 and E-cadherin levels were observed in cisplatin-sensitive A2780 cells. The highest E-cadherin level was noticed in OVCAR-3 cells. SNAIL1/2 expression was dependent on ERK1/2 activity in cisplatin-resistant and potentially invasive SK-OV-3 and OVCAR-3 cells. STAT-3 regulates expression of SNAIL1/2 and leads to the so-called “cadherin switch” in cancer cells, independently of their chemoresistance. In conclusion, SNAIL1, but not SNAIL2, seems to be involved in ovarian cancer cells’ cisplatin resistance. STAT3 is a universal factor determining the expression of SNAIL1/2 in ovarian cancer cells regardless of their chemoresitance or invasive capabilities.

Shear stress improves the endothelial progenitor cell function via the CXCR7/ERK pathway axis in the coronary artery disease cases

BACKGROUND

Dysfunction in the late Endothelial Progenitor Cells (EPCs) is responsible for endothelial repair in patients with Coronary Artery Disease (CAD), and the shear stress is beneficial for EPCs function. However, the impact of shear stress on the capacity of EPCs in CAD patients has not been elucidated yet. The C-X-C chemokine receptor 7/extracellular signal-regulated kinase (CXCR7)/(ERK) pathways are identified to regulate EPCs function in CAD patients. Here, we hypothesize that shear stress upregulates the CXCR7/ERK pathways, which restore the EPCs function in CAD patients.

METHODS

The human Peripheral Blood Mononuclear Cells (PBMCs) were collected from healthy adults and CAD patients and then used for EPCs cultivation. The Lv-siRNA for human CXCR7 was transfected into induced EPCs isolated from the CAD patients. Meanwhile, the EPCs from CAD patients were subjected to shear stress generated by a biomimetic device. Next, the cell viability, migration, tube formation, and apoptosis were detected by CCK-8, Transwell assay, Matrigel, and flow cytometry, respectively. Also, the CXCR7/ERK pathways in human EPCs were analyzed by Western blotting and qRT-PCR.

RESULT

Compared to the EPCs collected from normal adults, the CAD patient-derived EPCs showed reduced in vitro vasculogenic capacity. Also, the level of CXCR7 in CAD patient-derived EPCs was significantly reduced compared to the EPCs of healthy subjects. Meanwhile, the extracellular signal-regulated kinase (ERK), which represents a CXCR7 downstream signaling pathway, had decreased phosphorylation level. The shear stress treatment augmented the CXCR7 expression and also elevated ERK phosphorylation, which is comparable to the up-regulation of CAD patient-derived EPCs function. Further, the small interfering RNA (siRNA)-mediated CXCR7 knockdown diminished the enhanced migration, adhesion, and tube formation capacity of shear stress treated CAD patient-derived EPCs.

CONCLUSION

Up-regulation of the CXCR7/ERK pathways by shear stress can be a promising new target in enhancing the vasculogenic ability of CAD patient-derived EPCs.

Amyloid β precursor protein silencing attenuates epithelial‑mesenchymal transition of nasopharyngeal carcinoma cells via inhibition of the MAPK pathway

Advances in the treatment of nasopharyngeal carcinoma (NPC) have significantly improved the local control rate; however, distant metastasis remains a principal cause of mortality. Previous studies have demonstrated that the expression levels of amyloid β precursor protein (APP) are increased in NPC. The present study aimed to investigate the association between APP and the development of NPC. In order to knockdown APP expression, an APP-small interfering RNA vector was synthesized and transfected into SUNE-1 cells. Cell Counting Kit-8 assay was performed to assess cell viability. The migratory and invasive abilities of SUNE-1 cells were examined by wound healing and Transwell assays, respectively. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to measure the mRNA and protein expression levels of APP, and additional factors involved in epithelial-mesenchymal transition (EMT) and in the mitogen-activated protein kinase (MAPK) signaling pathway. APP silencing significantly suppressed cell viability, migration and invasion. In addition, APP interference downregulated the expression levels of metastasis-associated 1, matrix metalloproteinase (MMP)-2 and MMP-9; however, knockdown of APP led to upregulation of tissue inhibitor of metalloproteinases 2 and inhibited EMT. The phosphorylation levels of p38, extracellular signal-regulated kinases 1/2 and c-Jun N-terminal kinases 1/2 were decreased following downregulation of APP. The present results suggested that APP knockdown may significantly inhibit the development of NPC by suppressing cell viability, migration and invasion, and by inhibiting the EMT process via downregulation of the MAPK signaling pathway. Therefore, APP may facilitate the development of a novel gene therapy for the treatment of NPC.

Blocking TBK1 alleviated radiation-induced pulmonary fibrosis and epithelial-mesenchymal transition through Akt-Erk inactivation

As a common serious complication of thoracic radiotherapy, radiation-induced pulmonary fibrosis (RIPF) severely limits radiation therapy approaches. Epithelial–mesenchymal transition (EMT) is a direct contributor to the fibroblast pool during fibrogenesis, and prevention of EMT is considered an effective strategy to inhibit tissue fibrosis. Our previous study revealed that TANK-binding kinase 1 (TBK1) regulates EMT in lung cancer cells. In the present study, we aimed to investigate the therapeutic potential of targeting TBK1 to prevent RIPF and EMT progression. We found radiation-induced EMT and pulmonary fibrosis in normal alveolar epithelial cells and lung tissues. TBK1 knockdown or inhibition significantly reversed EMT in vivo and in vitro and attenuated pulmonary fibrosis and collagen deposition. Moreover, we observed that TBK1 was elevated in a time- and dose-dependent manner by radiation. Meanwhile, radiation also induced time- and dose-dependent activation of AKT and ERK, each of whose inhibitors suppressed radiation-induced EMT. Intriguingly, silencing of TBK1 with shRNA also blocked the radiation-induced activation of AKT and ERK signaling. The ERK inhibitor did not obviously affect the expression of TBK1 or phosphorylated AKT, while AKT inhibition suppressed activation of ERK without changing the expression of TBK1. Finally, we found that a TBK1 inhibitor inhibited inflammatory cytokine expression in a RIPF model and Amlexanox protected normal cells and mice from ionizing radiation. In conclusion, our results indicate that the TBK1–AKT–ERK signaling pathway regulates radiation-induced EMT in normal alveolar epithelial cells, suggesting that TBK1 is a potential target for pulmonary fibrosis prevention during cancer radiotherapy.

The risk of scarred tissues and respiratory distress during radiation treatment of lung cancer could be reduced by targeting an enzyme that alters healthy cells. Lung cancer radiotherapy often causes pulmonary fibrosis, excessive growth of fibrous tissues in the lungs, involving the transition of normal epithelial cells into an invasive form of multipotent stem cells. The development of pulmonary fibrosis limits the clinical application of radiotherapy. Hongjin Qu and co-workers at the Second Military University in Shanghai, China, previously demonstrated that the TANK-binding kinase 1 (TBK1) enzyme regulates this transition. Now, the team have shown that levels of TBK1 itself increased during radiation treatment, together with two proteins that would normally suppress alterations in healthy cells. Inhibiting TBK1, both in cell cultures and mouse models, reversed the cell transitions and prevented pulmonary fibrosis.

CXCR7 silencing inhibits the migration and invasion of human tumor endothelial cells derived from hepatocellular carcinoma by suppressing STAT3

C-X-C chemokine receptor type 7 (CXCR7) is reported to be overexpressed in tumor endothelial cells (TECs), which are the primary target cells of antivascular chemotherapy. However, the role of CXCR7 in TECs is not fully understood. In the present study, CXCR7 expression was inhibited in TECs derived from hepatocellular carcinoma (HCC) using short hairpin (sh)RNA plasmids to investigate the role of CXCR7 in the regulation of migration and invasion of TECs as well as its underlying mechanisms. The data showed that the downregulation of CXCR7 significantly inhibited the migration and invasion of TECs. Further study showed that silencing CXCR7 resulted in decreased phosphorylated signal transducer and activator of transcription 3 (STAT3) at Tyr705 and its downstream target genes in TECs, including matrix metalloproteinase‑2 (MMP2) and vascular endothelial growth factor (VEGF). However, restoring STAT3 phosphorylation abolished the CXCR7‑shRNA‑induced decrease in TECs migration and invasion, as well as the downregulation of MMP2 and VEGF in TECs. These findings indicate that CXCR7 may regulate the migration and invasion of TECs derived from HCC via the STAT3 signaling pathway and that CXCR7 could be a potential target for the antivascular therapy of HCC.

Biological/pathological functions of the CXCL12/CXCR4/CXCR7 axes in the pathogenesis of bladder cancer

CXC chemokine ligand 12 (CXCL12) is an important member of the CXC subfamily of chemokines, and has been extensively studied in various human body organs and systems, both in physiological and clinical states. Ligation of CXCL12 to CXCR4 and CXCR7 as its receptors on peripheral immune cells gives rise to pleiotropic activities. CXCL12 itself is a highly effective chemoattractant which conservatively attracts lymphocytes and monocytes, whereas there exists no evidence to show attraction for neutrophils. CXCL12 regulates inflammation, neo-vascularization, metastasis, and tumor growth, phenomena which are all pivotally involved in cancer development and further metastasis. Generation and secretion of CXCL12 by stromal cells facilitate attraction of cancer cells, acting through its cognate receptor, CXCR4, which is expressed by both hematopoietic and non-hematopoietic tumor cells. CXCR4 stimulates tumor progression by different mechanisms and is required for metastatic spread to organs where CXCL12 is expressed, thereby allowing tumor cells to access cellular niches, such as the marrow, which favor tumor cell survival and proliferation. It has also been demonstrated that CXCL12 binds to another seven-transmembrane G-protein receptor or G-protein-coupled receptor, namely CXCR7. These studies indicated critical roles for CXCR4 and CXCR7 mediation of tumor metastasis in several types of cancers, suggesting their contributions as biomarkers of tumor behavior as well as potential therapeutic targets. Furthermore, CXCL12 itself has the capability to stimulate survival and growth of neoplastic cells in a paracrine fashion. CXCL12 is a supportive chemokine for tumor neovascularization via attracting endothelial cells to the tumor microenvironment. It has been suggested that elevated protein and mRNA levels of CXCL12/CXCR4/CXCR7 are associated with human bladder cancer (BC). Taken together, mounting evidence suggests a role for CXCR4, CXCR7, and their ligand CXCL12 during the genesis of BC and its further development. However, a better understanding is still required before exploring CXCL12/CXCR4/CXCR7 targeting in the clinic.

Collagen triple helix repeat containing 1 (CTHRC1) activates Integrin β3/FAK signaling and promotes metastasis in ovarian cancer

BACKGROUND

Metastasis is the major cause of morbidity and mortality in patients with epithelial ovarian cancer (EOC), however the mechanisms that underline this process are poorly understood. Collagen triple helix repeat containing-1 (CTHRC1) is a 28-kDa secreted protein reported to be involved in vascular remodeling, bone formation and morphogenesis. This study aimed to investigate the role of CTHRC1 in promoting the metastasis of EOC and to elucidate the underlying molecular mechanisms.

METHODS

The biologic functions of CTHRC1 in metastasis were validated both in vivo and in vitro experiments. The phosphor-antibody microarray analysis and Co-immunoprecipitation were performed to detect and identify the integrin β3/FAK signaling pathway that mediated the function of CTHRC1. Seventy two EOC samples were analyzed for association between CTHRC1/integrin β3 expression and patient clinicopathological features.

RESULTS

We demonstrated that CTHRC1 enhances the biological behavior of EOC including cell migration, invasion, as well as its adhesion capability to cell-extracellular matrix in vitro. Additionally, CTHRC1 promoted metastatic spread of EOC cells in an i.p. ovarian xenograft model and this phenotype was primarily ascribed to the activation of integrin/FAK signaling. Mechanistically, we determined that FAK were phosphorylated on Tyr397, and were activated by integrin β3, which is important for the CTHRC1-mediated migratory and invasive ability of EOC cells in vitro and i.p. metastasis. In addition, we found that attenuated CTHRC1/integrin β3 expression predicted a poor prognostic phenotype and advanced clinical stage of EOC.

CONCLUSIONS

Our results suggest that CTHRC1, a newly identified regulator of i.p. metastasis through activation of integrin β3/FAK signaling in EOC, may represent a potential therapeutic target for ovarian cancer.

CXCL12 enhances angiogenesis through CXCR7 activation in human umbilical vein endothelial cells

Angiogenesis is the process by which new vessels form from existing vascular networks. Human umbilical vein endothelial cells (HUVECs) may contribute to the study of vascular repair and angiogenesis. The chemokine CXCL12 regulates multiple cell functions, including angiogenesis, mainly through its receptor CXCR4. In contrast to CXCL12/CXCR4, few studies have described roles for CXCR7 in vascular biology, and the downstream mechanism of CXCR7 in angiogenesis remains unclear. The results of the present study showed that CXCL12 dose-dependently enhanced angiogenesis in chorioallantoic membranes (CAMs) and HUVECs. The specific activation of CXCR7 with TC14012 (a CXCR7 agonist) resulted in the significant induction of tube formation in HUVECs and in vivo. Further evidence suggested that CXCL12 induced directional polarization and migration in the HUVECs, which is necessary for tube formation. Moreover, CXCR7 translocalization was observed during the polarization of HUVECs in stripe assays. Finally, treatment with TC14012 also significantly increased PI3K/Akt phosphorylation, and tube formation was blocked by treating HUVECs with an Akt inhibitor. Overall, this study indicated that CXCL12-stimulated CXCR7 acts as a functional receptor to activate Akt for angiogenesis in HUVECs and that CXCR7 may be a potential target molecule for endothelial regeneration and repair after vascular injury.

CXCL8 Antagonist Improves Diabetic Nephropathy in Male Mice With Diabetes and Attenuates High Glucose-Induced Mesangial Injury

Inflammation is recognized as a crucial contribution to diabetic nephropathy (DN). CXCL8 binds to its CXC chemokine receptors (CXCR1 and CXCR2) for recruiting neutrophil infiltration and initiates tissue inflammation. Therefore, we explored the effect of CXCR1 and CXCR2 inhibition on DN. This was achieved by CXCL8(3-72)K11R/G31P (G31P), an antagonist of CXCL8 that has exhibited therapeutic efficacy in inflammatory diseases and malignancies. In this study, we found that renal leukocyte accumulation and rapid increases of CXCL8 occurred in high-fat diet/streptozocin-induced diabetic mice. G31P effectively reduced urine volume, urine albumin/creatinine ratio, blood urea nitrogen, and creatinine clearance rate in mice with diabetes. In addition, renal histopathologic changes including mesangial expansion, glomerulosclerosis, and extracellular matrix deposition were partially moderated in G31P-treated diabetic mice. Furthermore, G31P attenuated renal inflammation and renal fibrosis of diabetic mice by inhibiting proinflammatory and profibrotic elements. G31P also inhibited high glucose-induced inflammatory and fibrotic factor upregulation in human renal mesangial cells. At the molecular level, G31P inhibited activation of CXCR1/2 downstream signaling JAK2/STAT3 and ERK1/2 pathways in in vitro and in vivo experiments. Our results suggest blockade of CXCR1/2 by G31P could confer renoprotective effects that offer potential therapeutic opportunities in DN.

Parametric analysis of colony morphology of non-labelled live human pluripotent stem cells for cell quality control

Given the difficulties inherent in maintaining human pluripotent stem cells (hPSCs) in a healthy state, hPSCs should be routinely characterized using several established standard criteria during expansion for research or therapeutic purposes. hPSC colony morphology is typically considered an important criterion, but it is not evaluated quantitatively. Thus, we designed an unbiased method to evaluate hPSC colony morphology. This method involves a combination of automated non-labelled live-cell imaging and the implementation of morphological colony analysis algorithms with multiple parameters. To validate the utility of the quantitative evaluation method, a parent cell line exhibiting typical embryonic stem cell (ESC)-like morphology and an aberrant hPSC subclone demonstrating unusual colony morphology were used as models. According to statistical colony classification based on morphological parameters, colonies containing readily discernible areas of differentiation constituted a major classification cluster and were distinguishable from typical ESC-like colonies; similar results were obtained via classification based on global gene expression profiles. Thus, the morphological features of hPSC colonies are closely associated with cellular characteristics. Our quantitative evaluation method provides a biological definition of ‘hPSC colony morphology’, permits the non-invasive monitoring of hPSC conditions and is particularly useful for detecting variations in hPSC heterogeneity.

Oroxylin A reverses the drug resistance of chronic myelogenous leukemia cells to imatinib through CXCL12/CXCR7 axis in bone marrow microenvironment

Imatinib (IM), a tyrosine-kinase inhibitor, is used in treatment of multiple cancers, most notably Philadelphia chromosome-positive (Ph⁺ ) chronic myelogenous leukemia (CML). However, the majority of patients continue to present with minimal residual disease occurred in the bone marrow (BM) microenvironment. One of the key factors that contribute to leukemia cell drug resistance is chemokine CXCL12. In the current study, co-culturing CML cell K562 and KU812 with BM stromal cell M2-10B4 attenuated IM-induced apoptosis. CXCL12/CXCR7 pathway was activated in co-culture models, which was further proved to be related to drug resistance by silencing CXCR7. ERK phosphorylation and downstream apoptosis related proteins' activation were also observed in co-culture group after the activation of CXCR7. Moreover, oroxylin A, a bioactive flavonoid isolated from the root of Scutellaria baicalensis Georgi, was found to be effective in reversing BM stroma induced CML resistance to IM. After cells were treated with weakly toxic concentration of oroxylin A, cell apoptosis induced by IM in co-culture model was enhanced. And the activated CXCL12/CXCR7 pathway, the expression of p-ERK and downstream apoptosis related proteins were suppressed. The in vivo study also showed that oroxylin A increased apoptosis of CML cells with low systemic toxicity, and the mechanism was consistent with the in vitro study. In conclusion, oroxylin A improved sensitivity of CML cells to IM treatment in BM microenvironment through regulating CXCL12/CXCR7 pathway. © 2016 Wiley Periodicals, Inc.

Xenograft of human umbilical mesenchymal stem cells from Wharton's jelly as a potential therapy for rat pilocarpine-induced epilepsy

We evaluated the effects of intra-hippocampal transplantation of human umbilical mesenchymal stem cells (HUMSCs) on pilocarpine-treated rats. Sprague-Dawley rats were divided into the following three groups: (1) a normal group of rats receiving only PBS, (2) a status epilepticus (SE) group of rats with pilocarpine-induced SE and PBS injected into the hippocampi, and (3) a SE+HUMSC group of SE rats with HUMSC transplantation. Spontaneous recurrent motor seizures (SRMS) were monitored using simultaneous video and electroencephalographic recordings at two to four weeks after SE induction. The results showed that the number of SRMS within two to four weeks after SE was significantly decreased in SE+HUMSCs rats compared with SE rats. All of the rats were sacrificed on Day 29 after SE. Hippocampal morphology and volume were evaluated using Nissl staining and magnetic resonance imaging. The results showed that the volume of the dorsal hippocampus was smaller in SE rats compared with normal and SE+HUMSCs rats. The pyramidal neuron loss in CA1 and CA3 regions was more severe in the SE rats than in normal and SE+HUMSCs rats. No significant differences were found in the hippocampal neuronal loss or in the number of dentate GABAergic neurons between normal and SE+HUMSCs rats. Compared with the SE rats, the SE+HUMSCs rats exhibited a suppression of astrocyte activity and aberrant mossy fiber sprouting. Implanted HUMSCs survived in the hippocampus and released cytokines, including FGF-6, amphiregulin, glucocorticoid-induced tumor necrosis factors receptor (GITR), MIP-3β, and osteoprotegerin. In an in vitro study, exposure of cortical neurons to glutamate showed a significant decrease in cell viability, which was preventable by co-culturing with HUMSCs. Above all, the expression of human osteoprotegerin and amphiregulin were significantly increased in the media of the co-culture of neurons and HUMSCs. Our results demonstrate the therapeutic benefits of HUMSC transplantation for the development of epilepsy, which are likely due to the ability of the cells to produce neuroprotective and anti-inflammatory cytokines. Thus, HUMSC transplantation may be an effective therapy in the future.

Overview and potential unifying themes of the atypical chemokine receptor family

Chemokines modulate immune responses through their ability to orchestrate the migration of target cells. Chemokines directly induce cell migration through a distinct set of 7 transmembrane domain G protein-coupled receptors but are also recognized by a small subfamily of atypical chemokine receptors, characterized by their inability to support chemotactic activity. Atypical chemokine receptors are now emerging as crucial regulatory components of chemokine networks in a wide range of physiologic and pathologic contexts. Although a new nomenclature has been approved recently to reflect their functional distinction from their conventional counterparts, a systematic view of this subfamily is still missing. This review discusses their biochemical and immunologic properties to identify potential unifying themes in this emerging family.