Functions of cofilin in cell locomotion and invasion.

Recently, a consensus has emerged that cofilin severing activity can generate free actin filament ends that are accessible for F-actin polymerization and depolymerization without changing the rate of G-actin association and dissociation at either filament end. The structural basis of actin filament severing by cofilin is now better understood. These results have been integrated with recently discovered mechanisms for cofilin activation in migrating cells, which led to new models for cofilin function that provide insights into how cofilin regulation determines the temporal and spatial control of cell behaviour.

CD301 mediates fusion in IL-4-driven multinucleated giant cell formation.

Multinucleated giant cells (MGCs) are prominent in foreign body granulomas, infectious and inflammatory processes, and auto-immune, neoplastic and genetic disorders, but the molecular determinants that specify the formation and function of these cells are not defined. Here, using tandem mass tag-mass spectrometry, we identified a differentially upregulated protein, C-type lectin domain family 10 member (herein denoted CD301, also known as CLEC10A), that was strongly upregulated in mouse RAW264.7 macrophages and primary murine macrophages undergoing interleukin (IL-4)-induced MGC formation. CD301+ MGCs were identified in biopsy specimens of human inflammatory lesions. Function-inhibiting CD301 antibodies or CRISPR/Cas9 deletion of the two mouse CD301 genes (Mgl1 and Mgl2) inhibited IL-4-induced binding of N-acetylgalactosamine-coated beads by 4-fold and reduced MGC formation by 2.3-fold (P<0.05). IL-4-driven fusion and MGC formation were restored by re-expression of CD301 in the knockout cells. We conclude that in monocytes, IL-4 increases CD301 expression, which mediates intercellular adhesion and fusion processes that are required for the formation of MGCs.This article has an associated First Person interview with the first author of the paper.

Does direct stenting with drug-eluting stents improve outcome? A meta-analysis of 10,900 patients.

OBJECTIVES: The aim of this study is to summarize the outcomes of patients undergoing direct stenting (DS) with drug-eluting stents (DES) compared to those who underwent balloon predilatation. BACKGROUND: DS has been associated with improved outcomes in the bare-metal stent era. Although DS with DES implantation has been increasingly adopted in clinical practice, its safety and effectiveness remain controversial. METHODS: The search criteria identified 546 studies in the Medline/PubMed, Cochrane, and EMBASE databases from 2001 to July 2014. From these, seven studies totaling 10,900 patients were selected. Summarized estimates [odds ratio (OR) and 95% confidence intervals] were obtained using a random-effects model. The primary outcomes were a composite of major adverse cardiac events (MACE), including all-cause death, myocardial infarction (MI), and repeat revascularization. The secondary outcomes included a composite of death and MI and the rates of target lesion revascularization (TLR). RESULTS: Overall, 4101 (38%) and 6799 (62%) patients underwent DS with DES and balloon pre-dilatation, respectively. DS with DES reduced the likelihood of MACE (OR: 0.81 [0.71-0.93]). Additionally, DS with DES was associated with reduced rates of death/MI (OR: 0.76 [0.62-0.92]), and TLR (OR: 0.66 [0.44-0.98]). CONCLUSIONS: DS with DES is safe and may be associated with better outcomes in selected patients. © 2016 Wiley Periodicals, Inc.

Clinical profiles and correlates of mortality in nonagenarians with severe aortic stenosis undergoing transcatheter aortic valve replacement.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is the current standard for nonoperable and high-risk surgical patients with aortic stenosis, including those of advanced age. However, the clinical profiles, procedural characteristics, and outcomes of nonagenarians undergoing TAVR have not been thoroughly reported. METHODS: A total of 654 patients (n = 107 >90 years old and n = 547 <90 years) with severe aortic stenosis undergoing TAVR were included in this analysis. Baseline characteristics, procedural variables, and in-hospital outcomes and complications at 30 days and 12 months were analyzed. RESULTS: Overall, of the patients included, 46% were high risk and 53% inoperable. Although nonagenarians had a higher Society of Thoracic Surgeons score of 9.2 ± 4 (12.1 ± 4 vs 8.6 ± 4, P < .001), other factors were considerably lower in this group: diabetes (22% vs 36%, P = .008), hyperlipidemia (65% vs 83%, P < .001), prior coronary artery bypass (13% vs 39%, P < .001), and mean body mass index (24.5 ± 5 vs 28.1 ± 7 kg/m(2), P < .001). The correlates for 1-year mortality in nonagenarians were as follows: ≥moderate aortic insufficiency post-TAVR (hazard ratio [HR] 5.07, 95% CI 1.17-22, P = .03), pacemaker implantation after TAVR (HR 6.87, 95% CI 2.32-20.3, P = .001), and peripheral vascular disease (HR 2.35, 95% CI 1.03-5.38, P = .042). Mortality at 30 days (12.1% vs 7.1%, P = .07) and at 1 year (25% vs 21%, P = .35) was similar between groups. CONCLUSION: Nonagenarians undergoing TAVR had a healthier clinical profile compared with younger patients. Age alone should not be a discriminatory factor when screening elderly patients with aortic stenosis because even the nonagenarians are doing well when compared with the younger elderly population. Transcatheter aortic valve replacement remains a viable option for the treatment of severe symptomatic aortic stenosis for the elderly regardless of their age.

Impact of baseline mitral regurgitation on short- and long-term outcomes following transcatheter aortic valve replacement.

BACKGROUND: The prevalence of concomitant significant mitral regurgitation (MR) in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) ranges from 2% to 33%. The impact of significant MR on post-TAVR outcomes remains controversial. METHODS: The data from a cohort of patients with symptomatic severe AS undergoing TAVR at out institution were retrospectively analyzed. The last transthoracic echocardiogram (TTE) before the index TAVR procedure was selected as the baseline assessment of the degree of MR. The total study cohort (N = 589) was divided into 2 groups: significant ≥moderate MR (n = 68) versus nonsignificant

Does the disparity in baseline characteristics of patients undergoing transcatheter aortic valve replacement with 23 mm vs. 26 mm valves impact clinical outcome?

OBJECTIVES: We sought to identify if baseline characteristic differences in patients who receive a 23 mm vs. 26 mm valve impact clinical outcomes. BACKGROUND: Transcatheter aortic valve replacement (TAVR) is currently an approved therapy for patients with severe aortic stenosis who are considered inoperable or are at high risk. METHODS: We retrospectively examined baseline characteristics and outcomes of patients receiving a 23 mm (n = 132) vs. 26 mm valve (n = 81) via the transfemoral approach. RESULTS: Gender (P < 0.01), previous coronary artery bypass surgery (P < 0.01), history of atrial fibrillation (P = 0.04), and mean Society of Thoracic Surgeons (STS) score (P < 0.01) were significantly different between groups. There were no significant differences in the rates of minor/major vascular complications (2.2 vs. 3.7%, P = 0.68 and 13.0 vs. 12.3%, P = 0.89, respectively). Bleeding complications were also comparable (major bleed 2.3 vs. 1%, P >0.99, minor bleed 19.0 vs. 22.0%, P = 0.67 and life threatening bleed 7.0 vs. 5.0%, P = 0.77). In-hospital death (6.0 vs. 5.0%, P >0.99), 30-day all-cause death (7.6 vs. 6.2%, P = 0.69), and all-cause death at 1 year (17.4 vs. 25.9%, P = 0.13) were also similar between groups. Gender, valve size, previous coronary bypass surgery and atrial fibrillation were not independently associated with mortality; however, on multivariate analysis STS score was (HR 1.11; 95% CI 1.02-1.19; P = 0.01). CONCLUSION: Patients undergoing TAVR with 23 and 26 mm valves have similar clinical outcomes despite significant differences in baseline characteristics. © 2015 Wiley Periodicals, Inc.

Active Versus Passive Anchoring Vascular Closure Devices Following Percutaneous Coronary Intervention: A Safety and Efficacy Comparative Analysis.

OBJECTIVE: We evaluate the prevalence of complications and failure rates between the most commonly used "active" anchoring vascular closure device (VCD), AngioSeal™ and the "passive" anchoring VCD, Mynx™, in all-comers undergoing percutaneous coronary intervention (PCI). METHODS: A total of 4,074 patients between 2008 and 2014, representing an era when both devices were available, were included. Thirty-two percent were acute coronary syndromes (37% STEMI). VCD choice was at the operator's discretion and included AngioSeal (n = 2,910) or Mynx (1,164). Cardiogenic shock or patients receiving intra-aortic balloon pumps were excluded. Safety was assessed by vascular complications defined as either vascular injury (perforation, dissection, acute limb ischemia, arteriovenous fistula, pseudoaneurysm with thrombin injection, or surgical repair) or access-site bleed (hemoglobin droP >3 g/dL requiring transfusion, retroperitoneal bleed, or hematoma >5 cm, or the composite of both. Efficacy was evaluated by device failure and defined as inability to achieve immediate hemostasis or use of additional hemostatic mechanisms. Outcomes at 30-days were evaluated. RESULTS: Groups (AngioSeal vs Mynx) were fairly balanced with regards to bleeding risk factors of gender (male, 65% vs 66%), body mass index (30 ± 6 vs 30 ± 7), heart failure class III/IV (5% vs 6%), chronic kidney disease (15% vs 17%), use of glycoprotein IIb/IIIa inhibitor (5% vs 4%), or bivalirudin (86% vs 88%), all P >0.5. The AngioSeal group was slightly younger (64 ± 12 vs 65 ± 12, P < 0.001) with less peripheral arterial disease (11.3% vs 13.9%, P = 0.03), and increased 7F sheath use compared with Mynx (59% vs 22%, P < 0.001). Safety and efficacy outcomes were similar between groups. CONCLUSIONS: AngioSeal and Mynx appear to be equally safe and efficacious VCDs following PCI. The passive anchoring system may prove desirable as no intra-arterial anchor remains upon device removal.

The choice of arterial access for percutaneous coronary intervention and its impact on outcome: An expert opinion perspective.

The prevention of major bleeding during percutaneous coronary intervention is one of the most widely discussed and often controversial topics within interventional cardiology. The choice of arterial access should be considered a mechanism for bleeding avoidance, and various strategies have been proposed to prevent or lower major bleeding and vascular complications with varying levels of strength. Herein, we review the current literature on arterial access as a bleeding avoidance strategy during percutaneous coronary intervention and its impact on outcome and provide a consensus opinion based on the strength of the evidence supporting various techniques.

Outcome comparison of African-American and Caucasian patients with severe aortic stenosis subjected to transcatheter aortic valve replacement: a single-center experience.

OBJECTIVE: This study aimed to report the outcomes of African Americans (AAs) in the US undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS). BACKGROUND: Compared to Caucasians, AAs are reported to have poorer outcomes from most cardiovascular diseases, including high complication rates after surgical aortic valve replacement. The outcomes of AAs undergoing TAVR are not well established. METHODS: Consecutive patients who underwent TAVR were included in this analysis. Patients' baseline characteristics, procedural data, in-hospital- and long-term outcomes were recorded and a comparison was performed between the AA and Caucasian cohorts. RESULTS: In a cohort of 469 consecutive patients, 51 (10.8%) were AA and 345 (74.5%) were Caucasian. The remaining patients (n = 73; 15.3%) self-reported their race as "unknown" or were from other races. Most baseline characteristics were similar between the two groups except for less men (33.3 vs. 50.1%; P = 0.016), a lower mean left ventricular ejection fraction (48.85 ± 16.35 vs. 53.24 ± 13.41%; P = 0.04) and lower rates of atrial fibrillation in AAs (15.7 vs.45.4%; P < 0.001). TAVR procedures in AAs were less frequently performed as part of a clinical trial (60.8 vs. 76.8%; P = 0.014). Most procedural and periprocedural outcome parameters were similar save for a higher rate of hemodynamic instability and postoperative need for intubation in AAs (10.4 vs. 2.5%; P = 0.018 and 29.4 vs. 16.9%; P = 0.03, respectively). This did not translate into a difference in mortality between AAs and Caucasians (30-day mortality 9.8 vs. 9.9%; P = 0.99; 1-year mortality 19.6 vs. 24.3%; P = 0.458, respectively). CONCLUSION: Unlike with other cardiovascular interventions, this study demonstrates that AA patients referred for TAVR shared similar risks and outcomes when compared to a Caucasian population.

Does baseline hematocrit influence the assays of on-treatment platelet reactivity to clopidogrel?

BACKGROUND: High on-treatment platelet reactivity (HTPR) has been shown to be associated with adverse cardiac events in patients undergoing percutaneous coronary intervention, but the effect of baseline hematologic parameters upon platelet reactivity remains controversial. OBJECTIVE: The present study aims to evaluate the impact of hematocrit on 2 different assay methods used to assess on-treatment platelet reactivity to clopidogrel. METHODS: We tested clopidogrel on-treatment platelet reactivity in 466 consecutive patients using VerifyNow P2Y12 (VN) and light transmission aggregometry (LTA) with adenosine diphosphate (ADP) 5 and 20 µM assays 6 to 24 hours after percutaneous coronary intervention. Patients were categorized into 4 groups according to baseline hematocrit. One-year major adverse cardiac events, including death, nonfatal myocardial infarction, and definite stent thrombosis, were collected. RESULTS: Lower hematocrit was associated with higher P2Y12 reaction unit (PRU) and a higher rate of HTPR (P < .001) as measured by VN assay. No differences were seen among the 4 groups in platelet reactivity measured by LTA using ADP 5 µM (P = .23) and ADP 20 µM (P = .21). In a multivariable logistic regression model, baseline hematocrit was independently associated with PRU ≥208 (odds ratio [OR] 0.92, 95% CI 0.86-0.97, P = .005) but had no correlation with LTA ADP 5 µM ≥46% (OR 1.0, 95% CI 0.95-1.06, P = .88) or LTA ADP 20 µM ≥59% (OR 1.03, 95% CI 0.97-1.09, P = .39). In a logistic regression model, the addition of VN assay results, hematocrit, and interaction between the hematocrit and assay results had shown a significant influence on the area under curve for prediction of 1-year major adverse cardiac events compared with baseline clinical variables only for PRU (0.63 vs 0.76, P = .006) but not with LTA (0.64 vs 0.74, P = .13). CONCLUSION: Baseline hematocrit has a differential influence on results of the ex vivo platelet functional assays. Lower baseline hematocrit was independently associated with HTPR by VN but not LTA. This may affect the interpretation of platelet function testing in patients with significant anemia.

Long-term safety and efficacy of second-generation everolimus-eluting stents compared to other limus-eluting stents and bare metal stents in patients with acute coronary syndrome.

OBJECTIVES: This study aimed to investigate the long-term safety and efficacy of everolimus-eluting stents (EES) compared with other limus-eluting stents and bare metal stents (BMS) in ACS patients. BACKGROUND: There have been concerns about the long-term safety of drug-eluting stents in the setting of acute coronary syndrome. METHODS: The study cohort included 1,612 patients presenting with acute coronary syndrome who underwent BMS, SES, E-ZES, or EES implantation. End points included probable or definite stent thrombosis and major adverse cardiovascular events (MACE), defined as a composite of all-cause death, Q-wave myocardial infarction, and target lesion revascularization up to 3 years. RESULTS: The overall MACE rates were significantly higher for both BMS and SES, but not E-ZES, when compared with EES (EES vs. BMS: HR 2.68, 95% CI 1.91-3.78, P <0.001; EES vs. SES: HR 1.75, 95% CI 1.24-2.47, P = 0.001 and EES vs. E-ZES: HR 1.08, 95% CI 0.65-1.77, P = 0.72). Stent thrombosis rates were similar for EES, E-ZES, and BMS but higher for SES throughout the 3-year follow-up (EES vs. BMS: HR 1.02, 95% CI: 0.31-3.35, P = 0.973; EES vs. SES: HR 4.90, 95% CI: 1.75-13.69, P = 0.002 and EES vs. E-ZES: HR 1.63, 95% CI 0.37-7.31, P = 0.449). CONCLUSIONS: There was an improvement in the long-term outcome for MACE with EES when compared to earlier-generation stents, but this was comparable with the 2nd-generation E-ZES. There was no additional risk of early or late stent thrombosis in EES when compared with BMS.

Intravascular ultrasound analysis to determine the relationship between high-density lipoprotein cholesterol and lesion characteristics in patients with coronary artery disease.

OBJECTIVES: This study utilized grayscale intravascular ultrasound (IVUS) to explore the relationship between high-density lipoprotein cholesterol (HDL-C) levels and culprit lesion characteristics in patients with coronary artery disease. BACKGROUND: Low HDL-C is associated with an increased risk of cardiovascular events. Previous IVUS studies have suggested a significant association between lesion characteristics and cardiovascular events. METHODS: According to HDL-C levels, 120 patients who underwent IVUS for native, de novo coronary lesions before any intervention were divided into a low HDL-C group (<40 mg/dL, n = 60) and a high HDL-C group (≥40 mg/dL, n = 60). Quantitative and qualitative IVUS analyses were performed to compare lesion characteristics. RESULTS: Quantitative IVUS measurements showed no significant differences between the 2 groups. HDL-C level was not significantly correlated with remodeling index (r = 0.03, P = 0.78). However, attenuated plaque was more frequent in the low HDL-C group (48.3% vs. 28.3%, P = 0.02) and a greater percentage of attenuated plaque was found in this group (32.5 ± 21.3% vs. 21.0 ± 11.0%, P = 0.02). Moreover, when categorized into 4 groups according to HDL-C levels, the proportion of attenuated plaque (64.7% in group with <30 mg/dL, 41.9% in group with 30-39 mg/dL, 36.4% in group with 40-59 mg/dL, and 6.3% in group with ≥60 mg/dL; P = 0.001 for trend) was significantly different among groups. On multivariate analysis, only HDL-C and male gender were independently associated with the presence of attenuated plaque at the culprit lesions. CONCLUSIONS: Patients with low levels of HDL-C may be at increased risk of having a higher incidence of attenuated plaques.

Rac regulates PtdInsP3 signaling and the chemotactic compass through a redox-mediated feedback loop.

Directional cell migration is an essential requirement for efficient neutrophil translocation to sites of infection and requires the establishment of a polarized cell characterized by an actin-rich leading edge facing the chemoattractant gradient. The asymmetrical accumulation of phosphatidylinositol(3,4,5)-trisphosphate [PtdIns(3,4,5)P(3)] in the up-gradient leading edge is a hallmark of polarization and regulates the recruitment and localization of various effector proteins at the leading-edge plasma membrane. How shallow gradients of chemoattractants trigger and maintain a much steeper intracellular gradient of PtdIns(3,4,5)P(3) is a critical question in the study of leukocyte chemotaxis. Our data demonstrate that the migration of neutrophils toward the chemoattractant N-formyl-L-methionyl-L-leucyl-L-phenylalanine depends on the generation of reactive oxygen species by the phagocytic NADPH oxidase (NOX2) and subsequent oxidation and inhibition of phosphatase and tensin homolog. Moreover, we show that events downstream of PtdIns(3,4,5)P(3), including phosphorylation of AKT, Rac activation, uncapping of actin filaments, and directional migration, can be attenuated by ROS scavengers or genetic ablation of NOX2. Using Rac mutants that are defective in their ability to activate NOX2, we show that Rac regulates a redox-mediated feedback loop that mediates directional migration of neutrophils.

Transcatheter aortic valve implantation through a diseased left common carotid artery: combined approach with endarterectomy and left carotid-subclavian bypass.

We report a case of transcatheter aortic valve implantation (TAVI) with the self-expanding Medtronic CoreValve bioprosthesis (Medtronic, Minneapolis, MI) through a diseased left common carotid (LCC) artery. This 81-year-old male patient presented with heart failure due to a severe degenerative aortic valve stenosis. Comorbidities included diabetes, hypertension, and dyslipidemia as well as peripheral and coronary artery disease, resulting in a logistic EuroScore II of 25.9%. Consequently, he was rejected to undergo surgery and a transcatheter approach was planned. Due to severe peripheral vascular disease with iliofemoral lesions, significant calcifications and unfavourable angulations of the innominate artery as well as prior bypass surgery precluding a direct aortic and subclavian approach, none of the established access sites were suitable. Therefore, we considered a left carotid access, which had to be combined with a surgical endarterectomy for treatment of a significant common carotid bifurcation stenosis and left subclavian-LCC permanent tunnel bypass graft. The procedure was successful without cardiac, cerebrovascular, or access complications. This case illustrates a true heart team approach, establishing a unique access for TAVI for patients without regular access options.

Progression to malignancy in oral potentially malignant disorders: a retrospective study of 5,036 patients in Ontario, Canada.

OBJECTIVES: Determine the rate of malignant transformation (MT) of oral potentially malignant disorders (OPMDs) and risk factors for transformation. STUDY DESIGN: The OPMD database (2001-2015) from 2 biopsy services in Ontario, Canada, was linked to the Ontario Cancer Registry to determine the rate of progression to oral squamous cell carcinoma (OSCC). Clinical and histologic features of progressed and non-progressed cases were compared to determine risk factors for progression. RESULTS: The MT rate was 6.4% (322/5,036 cases). The mean time for cancer development was 51.2 months. 33.6% of cases (107/322) progressed after over 60 months. The risk of cancer increased with age and was higher in non-smokers. The MT rate was highest in the tongue (11.4%), followed by the floor of mouth (7.1%) and gingiva (6.5%). Histologic grade was associated with progression to cancer (P < .0001). Atypical verrucous-papillary lesions with no or mild dysplasia predominantly affected older patients' gingiva, and the progression rate was significantly higher than conventional mild dysplasia (9.2% vs 3.2%, P = .0002). CONCLUSIONS: Our population-based retrospective study showed that <10% of OPMDs progressed to cancer, which could take many years. Atypical papillary-verrucous proliferation without high-grade dysplasia is a subtype of OPMD requiring further study.

Rac1 and Rac2 differentially regulate actin free barbed end formation downstream of the fMLP receptor.

Actin assembly at the leading edge of migrating cells depends on the availability of high-affinity free barbed ends (FBE) that drive actin filament elongation and subsequent membrane protrusion. We investigated the specific mechanisms through which the Rac1 and Rac2 small guanosine triphosphatases (GTPases) generate free barbed ends in neutrophils. Using neutrophils lacking either Rac1 or Rac2 and a neutrophil permeabilization model that maintains receptor signaling to the actin cytoskeleton, we assessed the mechanisms through which these two small GTPases mediate FBE generation downstream of the formyl-methionyl-leucyl-phenylalanine receptor. We demonstrate here that uncapping of existing barbed ends is mediated through Rac1, whereas cofilin- and ARP2/3-mediated FBE generation are regulated through Rac2. This unique combination of experimental tools has allowed us to identify the relative roles of uncapping (15%), cofilin severing (10%), and ARP2/3 de novo nucleation (75%) in FBE generation and the respective roles played by Rac1 and Rac2 in mediating actin dynamics.

Activation of antibacterial autophagy by NADPH oxidases.

Autophagy plays an important role in immunity to microbial pathogens. The autophagy system can target bacteria in phagosomes, promoting phagosome maturation and preventing pathogen escape into the cytosol. Recently, Toll-like receptor (TLR) signaling from phagosomes was found to initiate their targeting by the autophagy system, but the mechanism by which TLR signaling activates autophagy is unclear. Here we show that autophagy targeting of phagosomes is not exclusive to those containing TLR ligands. Engagement of either TLRs or the Fcgamma receptors (FcgammaRs) during phagocytosis induced recruitment of the autophagy protein LC3 to phagosomes with similar kinetics. Both receptors are known to activate the NOX2 NADPH oxidase, which plays a central role in microbial killing by phagocytes through the generation of reactive oxygen species (ROS). We found that NOX2-generated ROS are necessary for LC3 recruitment to phagosomes. Antibacterial autophagy in human epithelial cells, which do not express NOX2, was also dependent on ROS generation. These data reveal a coupling of oxidative and nonoxidative killing activities of the NOX2 NADPH oxidase in phagocytes through autophagy. Furthermore, our results suggest a general role for members of the NOX family in regulating autophagy.

Opposing roles of CXCR4 and CXCR7 in breast cancer metastasis.

INTRODUCTION: CXCL12-CXCR4 signaling has been shown to play a role in breast cancer progression by enhancing tumor growth, angiogenesis, triggering cancer cell invasion in vitro, and guiding cancer cells to their sites of metastasis. However, CXCR7 also binds to CXCL12 and has been recently found to enhance lung and breast primary tumor growth, as well as metastasis formation. Our goal was to dissect the contributions of CXCR4 and CXCR7 to the different steps of metastasis - in vivo invasion, intravasation and metastasis formation. METHODS: We overexpressed CXCR4, CXCR7 or both in the rat mammary adenocarcinoma cell line MTLn3. Stable expressors were used to form tumors in severe combined immunodeficiency (SCID) mice, and in vivo invasiveness, intravital motility, intravasation, and metastasis were measured. RESULTS: We found that CXCR4 overexpression increased the chemotactic and invasive behavior of MTLn3 cells to CXCL12, both in vitro and in vivo, as well as in vivo motility and intravasation. CXCR7 overexpression enhanced primary tumor growth and angiogenesis (as indicated by microvessel density and VEGFA expression), but decreased in vivo invasion, intravasation, and metastasis formation. In vitro, expression of CXCR7 alone had no effect in chemotaxis or invasion to CXCL12. However, in the context of increased CXCR4 expression, CXCR7 enhanced chemotaxis to CXCL12 but decreased invasion in response to CXCL12 in vitro and in vivo and impaired CXCL12 stimulated matrix degradation. The changes in matrix degradation correlated with expression of matrix metalloproteinase 12 (MMP12). CONCLUSIONS: We find that CXCR4 and CXCR7 play different roles in metastasis, with CXCR4 mediating breast cancer invasion and CXCR7 impairing invasion but enhancing primary tumor growth through angiogenesis.

TNFα Signaling Is Increased in Progressing Oral Potentially Malignant Disorders and Regulates Malignant Transformation in an Oral Carcinogenesis Model.

Oral carcinogenesis represents a multi-stage process which encompasses several genetic and molecular changes that promote the progression of oral potentially malignant disorders (OPMDs) to oral squamous cell carcinomas (OSCCs). A better understanding of critical pathways governing the progression of OMPDs to OSCCs is critical to improve oncologic outcomes in the future. Previous studies have identified an important role of tumor necrosis factor α (TNFα) and TNF receptor 1 (TNFR1) in the invasiveness of oral cancer cell lines. Here, we investigate the expression of TNFα and TNFR1 in human OPMDs that progress to OSCC compared to non-progressing OPMDs utilizing fluorescent immunohistochemistry (FIHC) to show increased TNFα/TNFR1 expression in progressing OPMDs. In order to interrogate the TNFα/TNFR1 signaling pathway, we utilized a 4-nitroquinoline 1-oxide (4-NQO) mouse model of oral carcinogenesis to demonstrate that TNFα/TNFR1 expression is upregulated in 4-NQO-induced OSCCs. TNFα neutralization decreased serum cytokines, inhibited the development of invasive lesions and reduced tumor-associated neutrophils in vivo. Combined, this data supports the role of TNFα in oral malignant transformation, suggesting that critical immunoregulatory events occur downstream of TNFR1 leading to malignant transformation. Our results advance the understanding of the mechanisms governing OSCC invasion and may serve as a basis for alternative diagnostic and therapeutic approaches to OPMDs and OSCC management.

Oral Squamous Cell Carcinoma Associated with Precursor Lesions.

Oral squamous cell carcinoma (OSCC) may be associated with precursor lesions known as oral potentially malignant disorders (OPMD). Few studies have reported on how OPMD diagnosis affects early detection and outcome of OSCC. We reviewed a large series of OSCC to determine the proportion that was associated with preceding OPMD and to compare the outcome of OSCC with or without precursor. Cases of oral-oropharyngeal carcinoma diagnosed between 2005 and 2015 were retrieved from the Ontario Cancer Registry (OCR) and matched to records of OPMD between 2001 and 2015 in two large oral pathology diagnostic services and the pathology databases of two hospitals with oral pathology services, to identify cases with precursor. Of 10,987 cancer cases, 378 (3.44%) had a preceding OPMD. Patients living in Central Ontario were more likely to have OPMD diagnosed before carcinoma than those in North Ontario (4.73% vs. 1.63%, P = 0.05). 329 of 5,257 cases of oral cancer were linked to a precursor, compared with 24 of 4,174 cases of oropharyngeal cancer (6.26% vs. 0.57%, P < 0.0001). Oral cancers with precursor were predominantly diagnosed at stage I (49.30%), compared with those without precursor, where stage IV disease predominated (41.28%). Sixty-nine of 309 (22.33%) patients with precursor-associated oral cancer have died of disease, compared with 1,551 of 4,656 (33.31%) patients without a precursor (P = 0.02). We conclude that patients with OSCC associated with a precursor had significantly lower odds of dying from disease. The beneficial effect of precursor lesion diagnosis on outcome is related to a higher proportion of stage I disease. PREVENTION RELEVANCE: OSCC causes significant morbidity and mortality, especially if diagnosed at late stages. Precursor lesions to OSCC can be recognized by clinical examination. Our study shows that early diagnosis of OSCC at the precursor stage can improve the outcome of oral cancer.