ROCK inhibition modulates the senescence‐associated secretory phenotype (SASP) in oral keratinocytes

Senescent cells accumulate in different organs and develop a senescence‐associated secretory phenotype (SASP), associated with the development of age‐related pathologies. The constitution of the SASP varies among cell types and with the method of senescence induction; nevertheless, there is substantial overlap among SASPs, especially the presence of pro‐inflammatory cytokines such as IL‐1β, IL‐1α, IL‐6 and IL‐8. These cytokines are highly conserved among SASPs and are implicated in the development of several cancers. Here, we report that ROCK inhibition by Y‐27632 reduces levels of IL‐1α, IL‐1β, IL‐6 and IL‐8 secreted by senescent normal and dysplastic oral keratinocytes without affecting the permanent cell growth arrest. The data indicate some inflammatory genes downregulated by Y‐27632 remain downregulated even after repeated passage in the absence of Y‐27632. We propose ROCK kinase inhibition as a novel alternative to current strategies to modulate the inflammatory components of the SASP, without compromising the permanent cell growth arrest. This observation potentially has wide clinical applications, given the involvement of senescence in cancer and a wide range of age‐related disease. It also suggests care should be exercised when using Y‐27632 to facilitate cell expansion of primary cells, as its effects on gene expression are not entirely reversible

Endothelin-1 stimulates oral fibroblasts to promote oral cancer invasion

AbstractAimsThe aims of this study were to examine the role of endothelin-1 (ET-1), a pleiotropic peptide found at elevated levels in a number of malignancies and which has been shown to influence oral cancer cell behaviour via paracrine signalling pathways, on the phenotype of oral fibroblasts.Main methodsThe effect of ET-1 on proliferation and migration of human primary oral fibroblasts was assessed using MTS and scratch assays, respectively. The ability of ET-1 to affect fibroblast contractility was analysed using type-I collagen gels. Changes in gene expression in oral fibroblasts exposed to ET-1 were examined using quantitative PCR. The invasiveness of oral cancer cells in the presence of conditioned media collected from ET-1 treated fibroblasts was determined using 2D Matrigel assays.Key findingsHere we provide evidence that ET-1 increases the migration of oral fibroblasts and induces a more contractile phenotype which is not associated with changes in gene expression indicative of myofibroblast transdifferentiation. In addition we provide evidence that conditioned medium of ET-1-stimulated oral fibroblasts promotes invasion of OSCC cells in vitro.SignificanceIn oral squamous cell carcinoma, a frequently fatal and increasingly common epithelial malignancy of the oral cavity, ET-1 is known to contribute to pro-migratory paracrine signalling between stromal fibroblasts and cancer cells. The ability of ET-1 to modulate the phenotype of human oral stromal fibroblasts, however, has not previously been reported. The findings presented here suggest that targeting the stromal endothelin system may be a viable and novel therapeutic strategy for invasive oral cancer

Senescent cells in cancer : wanted or unwanted citizens

Over recent decades, the field of cellular senescence has attracted considerable attention due to its association with aging, the development of age-related diseases and cancer. Senescent cells are unable to proliferate, as the pathways responsible for initiating the cell cycle are irreversibly inhibited. Nevertheless, senescent cells accumulate in tissues and develop a pro-inflammatory secretome, known as the senescence-associated secretory phenotype (SASP), which can have serious deleterious effects if not properly regulated. There is increasing evidence suggesting senescent cells contribute to different stages of carcinogenesis in different anatomical sites, mainly due to the paracrine effects of the SASP. Thus, a new therapeutic field, known as senotherapeutics, has developed. In this review, we aim to discuss the molecular mechanisms underlying the senescence response and its relationship with cancer development, focusing on the link between senescence-related inflammation and cancer. We will also discuss different approaches to target senescent cells that might be of use for cancer treatment

Targeting HOX-PBX interactions causes death in oral potentially malignant and squamous carcinoma cells but not normal oral keratinocytes

YesBackground: High HOX gene expression has been described in many cancers, including oral squamous cell carcinoma and the functional roles of these genes are gradually being understood. The pattern of overexpression suggests that inhibition may be useful therapeutically. Inhibition of HOX protein binding to PBX cofactors by the use of synthetic peptides, such as HXR9, results in apoptosis in multiple cancers. Methods: Activity of the HOX-PBX inhibiting peptide HXR9 was tested in immortalised normal oral (NOK), potentially-malignant (PMOL) and squamous cell carcinoma (OSCC) cells, compared to the inactive peptide CXR9. Cytotoxicity was assessed by LDH assay. Expression of PBX1/2 and c-Fos was assessed by qPCR and western blotting. Apoptosis was assessed by Annexin-V assay. Results: PMOL and OSCC cells expressed PBX1/2. HOX-PBX inhibition by HXR9 caused death of PMOL and OSCC cells, but not NOKs. HXR9 treatment resulted in apoptosis and increased expression of c-Fos in some cells, whereas CXR9 did not. A correlation was observed between HOX expression and resistance to HXR9. Conclusion: Inhibition of HOX-PBX interactions causes selective apoptosis of OSCC/PMOL, indicating selective toxicity that may be useful clinically.Intercalated Degree Scholarship from the Harry Bottom Trust; scholarship by Becas Chile, Comisión Nacional de Investigación Científica y Tecnológica de Chile (CONICYT), Grant 7216004

HPV-negative, but not HPV-positive, oropharyngeal carcinomas induce fibroblasts to support tumour invasion through micro-environmental release of HGF and IL-6.

Human papillomavirus (HPV) infection is causally related to a subset of oropharyngeal carcinomas (OPC) and is linked to a more favourable prognosis compared to HPV-negative OPC. The mechanisms underlying this effect on prognosis are not fully understood, but interactions with the tumour microenvironment may be pivotal. Here, we investigated the role of the tumour microenvironment in HPV-positive compared to HPV-negative cancer using 2D and 3D modelling of OPC interactions with stromal fibroblasts. HPV-negative, but not HPV-positive, OPC-derived cell lines induced a rapid fibroblast secretory response that supported 2D cancer cell migration and invasion in vitro. Array profiling of this HPV-negative induced fibroblast secretome identified hepatocyte growth factor (HGF) as the principal secreted factor that promoted cancer cell migration. The interaction between HPV-negative cell lines and fibroblasts in 2D was prevented using c-Met (HGF receptor) inhibitors, which further restricted both HPV-negative and positive cell invasion in 3D co-culture models. Furthermore, we discovered a synergistic relationship between HGF and IL-6 in the support of migration that relates JAK activation to HGF responsiveness in HPV-negative lines. In summary, our data show significant differences in the interactions between HPV-positive and HPV-negative OPC cells and stromal fibroblasts. In addition, we, provide in vitro evidence to support the clinical application of c-MET inhibitors in the control of early HPV-negative OPC

The roles of HOXD10 in the development and progression of head and neck squamous cell carcinoma (HNSCC).

Background: HOX gene expression is altered in many cancers; previous microarray revealed changes in HOX gene expression in head and neck squamous cell carcinoma (HNSCC), particularly HOXD10. Methods: HOXD10 expression was assessed by qPCR and immunoblotting in vitro and by immunohistochemistry (IHC) in tissues. Low-expressing cells were stably transfected with HOXD10 and the phenotype assessed with MTS, migration and adhesion assays and compared with the effects of siRNA knockdown in high-HOXD10-expressing cells. Novel HOXD10 targets were identified using expression microarrays, confirmed by reporter assay, and validated in tissues using IHC. Results: HOXD10 expression was low in NOKs, high in most primary tumour cells, and low in lymph node metastasis cells, a pattern confirmed using IHC in tissues. Overexpression of HOXD10 decreased cell invasion but increased proliferation, adhesion and migration, with knockdown causing reciprocal effects. There was no consistent effect on apoptosis. Microarray analysis identified several putative HOXD10-responsive genes, including angiomotin (AMOT-p80) and miR-146a. These were confirmed as HOXD10 targets by reporter assay. Manipulation of AMOT-p80 expression resulted in phenotypic changes similar to those on manipulation of HOXD10 expression. Conclusions: HOXD10 expression varies by stage of disease and produces differential effects: high expression giving cancer cells a proliferative and migratory advantage, and low expression may support invasion/metastasis, in part, by modulating AMOT-p80 levels

Dynamical modelling of the elliptical galaxy NGC 2974

In this paper we analyse the relations between a previously described oblate Jaffe model for an ellipsoidal galaxy and the observed quantities for NGC 2974, and obtain the length and velocity scales for a relevant elliptical galaxy model. We then derive the finite total mass of the model from these scales, and finally find a good fit of an isotropic oblate Jaffe model by using the Gauss-Hermite fit parameters and the observed ellipticity of the galaxy NGC 2974. The model is also used to predict the total luminous mass of NGC 2974, assuming that the influence of dark matter in this galaxy on the image, ellipticity and Gauss-Hermite fit parameters of this galaxy is negligible within the central region, of radius $0.5R_{\rm e}.$Comment: 7 figure

Automated analysis of atrial late gadolinium enhancement imaging that correlates with endocardial voltage and clinical outcomes: A 2-center study

This work was supported by the British Heart Foundation PG/10/37/28347, RG/10/11/28457, NIHR Biomedical Research Centre funding, and the ElectroCardioMaths Programme of the Imperial BHF Centre of Research Excellence

HOPX functions as a tumour suppressor in head and neck cancer.

Head and neck squamous cell carcinoma (HNSCC) is generalized term that encompasses a diverse group of cancers that includes tumours of the oral cavity (OSCC), oropharynx (OPSCC) and nasopharynx (NPC). Genetic alterations that are common to all HNSCC types are likely to be important for squamous carcinogenesis. In this study, we have investigated the role of the homeodomain-only homeobox gene, HOPX, in the pathogenesis of HNSCC. We show that HOPX mRNA levels are reduced in OSCC and NPC cell lines and tissues and there is a general reduction of HOPX protein expression in these tumours and OPSCCs. HOPX promoter methylation was observed in a subset of HNSCCs and was associated with a worse overall survival in HPV negative tumours. RNAseq analysis of OSCC cells transfected with HOPX revealed a widespread deregulation of the transcription of genes related to epithelial homeostasis and ectopic over-expression of HOPX in OSCC and NPC cells inhibited cell proliferation, plating efficiency and migration, and enhanced sensitivity to UVA-induced apoptosis. Our results demonstrate that HOPX functions as a tumour suppressor in HNSCC and suggest a central role for HOPX in suppressing epithelial carcinogenesis

Archaeological signatures of landscape and settlement change on the Isle of Harris

Between 2004 and 2011, a programme of archaeological investigation by the University of Birmingham on the Isle of Harris, a distinctive island forming part of the Western Isles of Scotland, has allowed the archaeological remains of this enigmatic place to be further characterised and understood. Despite intensive archaeological interest in the archipelago for a number of decades, the Isle of Harris has been overlooked and only now are we beginning to identify the archaeological resource and make comparisons to the wealth of published data from islands such as the Uists, Barra and Lewis. This paper highlights some generic overall patterns of archaeological signatures on the Isle which has been identified through a range of archaeological methods including field walking, intrusive excavation, aerial reconnaissance, geophysical and topographical survey, and documentary research. Several key case studies will be introduced including upland shieling complexes and mulitperiod settlement sites on the west coast machair systems. The purpose of the paper is not to present a gazetteer of the results of the work to date, but to highlight some of the key findings with a view to demonstrating that the Isle of Harris is directly comparable with the archaeologically rich landscapes of the other islands