Papers by Philip J Coates
Journal of Oral Pathology & Medicine, 2010
Lichen planus is a chronic inflammatory disease of mucosa and skin affecting approximately 1-2% o... more Lichen planus is a chronic inflammatory disease of mucosa and skin affecting approximately 1-2% of the adult population. Autoimmunity has been implicated in the etiology of this disease, and recently we detected antibodies directed against all six p63 isoforms in sera from 2 out of 20 patients diagnosed with oral lichen planus (OLP) using Western blot analysis. Here we have developed an ELISA method for screening sera for presence of autoantibodies directed against p63. Using the same sera as previously analysed, we show that the optical density ratios for sera from the two patients with known autoantibodies was considerably higher compared to mean optical density ratios for all samples as well as controls analysed. Applying this novel ELISA technique for screening of sera from an additional group of 46 patients with oral and/or genital or skin lichen and 43 matched controls, we detected another three patients with autoantibodies against the p63 proteins. These data are discussed together with the observation that all five patients with detectable p63 autoantibodies from our two studies had clinically severe disease symptoms.
Journal of Investigative Dermatology, 2006
Psoriasis is a chronic and excessive inflammation of the skin and is currently incurable. The cau... more Psoriasis is a chronic and excessive inflammation of the skin and is currently incurable. The cause of psoriasis remains poorly understood and a central and cooperative role for keratinocytes and T-cells in triggering the disease is highlighted. The p63 gene encodes six different proteins with homology to the tumor suppressor protein p53 that are crucial for normal development of ectodermally derived structures such as skin and oral mucosa. In this study, we have analyzed levels of the different p63 isoforms using quantitative reverse transcriptionpolymerase chain reaction (RT-PCR) and immunohistochemistry in 15 patients diagnosed with psoriasis. Quantitative RT-PCR results showed downregulation of the full-length TAp63 in psoriatic lesions compared to both clinically normal skin from patients (Po0.001) and matched healthy controls (Po0.001); however, p63 protein levels detected by immunohistochemistry were similar. All psoriasis lesions also had detectable levels of activated Stat3, a protein indicated in development of the disease, whereas control tissue lacked this protein. The present data show a different regulation of TAp63 in psoriasis, where the discrepancy between mRNA levels and protein expression indicates a post-transcriptional regulation analogous to that seen in p53.
Acta Dermato Venereologica, 2011
Psoriasis is an inflammatory skin disease in which dysregulation of p63, a member of the p53 fami... more Psoriasis is an inflammatory skin disease in which dysregulation of p63, a member of the p53 family that is crucial for skin development and maintenance, has been demonstrated. Involvement of miR-203, miR-21 and miR-125b, small non-coding RNAs implicated in the regulation of p63 or p53, has been suggested in the pathogenesis of psoriasis. To elucidate the roles of p63 and p63-related microRNAs in psoriasis and to increase our understanding of the mechanisms of narrow-band ultraviolet B (NB-UVB) phototherapy, we studied the effects of NB-UVB treatment on the expression of these molecules. Skin biopsies from 12 psoriasis patients were collected before, during and after NB-UVB therapy. Real-time PCR and immunohistochemistry showed that p63 expression was not significantly affected, whereas NB-UVB phototherapy significantly decreased expression of miR-21 (p = 0.003) and increased miR-125b levels (p = 0.003). The results indicate that the unresolved p63 abnormality in treated epidermis may play a role in maintenance of this disease.
The Journal of Pathology, 2009
The p53 homologue p63 produces six different isoforms that are important in development of epithe... more The p53 homologue p63 produces six different isoforms that are important in development of epithelial tissues and squamous cell carcinoma of the head and neck (SCCHN). In SCCHN, the expression of p63 isoforms is highly complex, with over-expression of Np63 and p63β isoforms in many tumours. To date, little is known about the functions of different Np63 isoforms and elucidating the distinctive properties of Np63 isoforms will help to clarify how they influence tumour biology. By gene expression profiling of SCCHN cells over-expressing the Np63 isoforms we identified different effects of the three isoforms, with Np63β being more effective at gene induction than Np63α and Np63γ , whereas Np63γ was most effective at repressing gene expression. Thus, tumours expressing even low levels of Np63β or Np63γ may have distinct clinicopathological characteristics important for metastasis and therapeutic response. Induction of cyclooxygenase-2 (Cox-2) was shown by each isoform and data were confirmed by independent quantitative RT-PCR and western blotting. No direct binding of Np63 to the Cox-2 promoter could be seen, neither could any evidence for Cox-2 induction as a consequence of activated NF-κB pathway responses be found. As Cox-2 is known to inhibit radiotherapy responses in SCCHN patients, data indicate an additional mechanism through which Np63 acts to promote cell survival and influence therapeutic response of SCCHN. MIAME-compliant data have been deposited in the MIAME Express database (Accession Cell pellets from the different p63 over-expressing clones were collected and lysed in 200 µl buffer A
TRAF4 is potently induced by TAp63 isoforms and localised according to differentiation in SCCHN
Cancer Biology & Therapy, 2007
p63, a member of the p53 family, is overexpressed in squamous cell carcinoma of the head and neck... more p63, a member of the p53 family, is overexpressed in squamous cell carcinoma of the head and neck (SCCHN) and some other tumors of epithelial origin. As a transcription factor, p63 can bind to p53-type response elements and there is some overlap between p53 family transcriptional targets. Tumor necrosis factor receptor associated factor 4 (TRAF4) is a p53 regulated gene which is overexpressed in many human carcinomas. We investigated the involvement of p63 in regulation of TRAF4 and the expression of the TRAF4 protein in SCCHN. Disrupting endogenous p63 expression resulted in downregulation of TRAF4 mRNA and protein in an SCCHN cell line. Endogenous p63 bound to the TRAF4 promoter in vivo and reporter assays showed that p63, p73 and p53 can all transactivate TRAF4, with TAp63 isoforms being the most potent activators. The level of TRAF4 activation by TAp63 was two-fold higher than by p53, and TRAF4 was ten-fold more responsive to TAp63 than another p63-target, IGFBP3. Nuclear expression of TRAF4 was seen in normal oral epithelium and highly/moderately differentiated SCCHN, whereas cytoplasmic expression of TRAF4 was seen in poorly differentiated SCCHN. These results indicate that TRAF4 is a common target of p53 family members and that localization of TRAF4 is associated with differentiation of SCCHN cells.
ΔNp63 isoforms regulate CD44 and keratins 4, 6, 14 and 19 in squamous cell carcinoma of head and neck
The Journal of Pathology, 2007
ABSTRACT The human p63 gene codes for multiple protein isoforms and is commonly over-expressed in... more ABSTRACT The human p63 gene codes for multiple protein isoforms and is commonly over-expressed in squamous cell carcinoma of head and neck (SCCHN). This expression is predominantly of the DeltaN- and beta-isoforms, the former lacking the p53-related transactivation domain. p63 can activate or repress transcription of p53 and p73 target genes, but also has unique transcriptional targets and, unlike other p53 family members, is required for normal development and differentiation of squamous epithelia. We have identified novel targets of p63, using microarray analysis of SCCHN cells that stably over-express individual DeltaNp63 isoforms. All three isoforms induced expression of the cancer stem cell marker, CD44, with the DeltaNp63beta isoform showing strongest induction. Using chromatin immunoprecipitation, we were unable to show direct binding of p63 to the CD44 promoter, but found that p63 specifically increased expression of CD44 lacking variant exon 2. Each of the DeltaNp63 isoforms up-regulated expression of keratins 6A and 14 and down-regulated expression of keratins 4 and 19, in keeping with their expression patterns in SCCHN. The data strengthen the idea that p63 has key roles in regulating normal and abnormal differentiation processes through both induction and repression of genes with opposite functions. The identification of up-regulation and differential splicing of CD44 following p63 over-expression indicates roles in the regulation of adhesion, metastasis and the cancer stem cell phenotype.
Cancer Letters, 2008
The transcription factor p63 is commonly over-expressed in squamous cell carcinomas of the head a... more The transcription factor p63 is commonly over-expressed in squamous cell carcinomas of the head and neck (SCCHN). By microarray analysis of p63-siRNA-treated SCCHN cells we identified 127 genes whose expression relies on over-expression of p63. More than 20% of these genes are involved in cell motility. Chromatin immunoprecipitation and reporter assay revealed PAI-1 and AQP3 as direct p63 transcriptional targets. In addition to PAI-1, most of the key cell motility-related molecules are up-regulated by p63, such as MMP14 and LGALS1. Our findings indicate a contribution by p63 in cell invasion and migration, supporting an oncogenic role for p63 in SCCHN.
Exclusion of p63 as a candidate gene for autosomal-dominant amelogenesis imperfecta
Acta Odontologica Scandinavica, 2006
Mutations within the p63 gene have been shown to cause ectodermal dysplasia syndromes affecting a... more Mutations within the p63 gene have been shown to cause ectodermal dysplasia syndromes affecting a spectrum of developmental abnormalities, including ectodermal appendages, e.g. enamel. The affected teeth have a similar phenotype as another dental disorder, amelogenesis imperfecta (AI), a disease of genetically determined abnormal enamel formation in the absence of systemic symptoms. The genetic basis of particular forms of AI has been found, although the gene(s) responsible for the most prevalent AI types has not been identified. DNA samples of 41 individuals (25 affected and 16 unaffected) from 6 Swedish families with autosomal-dominant AI were screened for mutations (by partially denaturing HPLC) and sequenced. No mutation in p63 was found in these families. p63 is not responsible for different forms of autosomal-dominant AI in the Swedish families studied. The roles of p63 in tooth development and in the genetic etiology of AI remain to be identified.
Oxidation Reduction is a Key Process for Successful Treatment of Psoriasis by Narrow-band UVB Phototherapy
Acta Dermato Venereologica, 2015
Narrow-band UVB (NB-UVB) phototherapy is commonly used for treatment of psoriasis, though the mec... more Narrow-band UVB (NB-UVB) phototherapy is commonly used for treatment of psoriasis, though the mechanisms underlying its efficacy have not been completely elucidated. We used gene expression profiling to characterise gene expression in lesional epidermis from psoriasis patients in the middle and late stages of NB-UVB photo-therapy. Increased melanogenesis gene expression was the earliest response to phototherapy. At the end of treatment, genes responding to phototherapy and correlated to treatment outcome were involved in oxidation reduction, growth and mitochondria organisation. Particularly, SPATA18, a key regulator of mitochondrial quality, was significantly down-regulated in psoriasis (p < 0.05). Poly(dA:dT) and poly(I:C) stimulation increased SPATA18 level in primary keratinocytes, indicating the importance of mitochondria quality control under innate immune induced oxidative stress. Normalised SPATA18 expression after phototherapy indicates improved mitochondrial quality control and restored cellular redox status. Our data suggest that oxidation reduction is critical for the resolution of psoriatic plaques following NB-UVB phototherapy.
Decreased expression of the p63 related proteins β-catenin, E-cadherin and EGFR in oral lichen planus
Oral Oncology, 2008
Oral lichen planus (OLP) is a chronic inflammatory disease and although classified by WHO as a pr... more Oral lichen planus (OLP) is a chronic inflammatory disease and although classified by WHO as a premalignant condition, the risk for transformation into squamous cell carcinoma of the head and neck (SCCHN) is a matter of great controversy. The p63 gene encodes six different proteins which are required for development of ectodermally derived tissues such as oral mucosa, salivary glands, teeth and skin. p63 is highly expressed in SCCHN whereas decreased expression is seen in OLP. beta-catenin, E-cadherin and epidermal growth factor receptor (EGFR) are p63 related proteins, and abnormalities in their expression suggested they are involved in development of squamous cell carcinoma of the head and neck (SCCHN). In this study we mapped the expression of these p63 related proteins in OLP and matched normal healthy controls. Results showed decreased expression of beta-catenin, E-cadherin and EGFR in the vast majority of OLP samples compared with the normal controls. This is the first comprehensive study mapping expression of several p63- and SCCHN-related proteins in tissue from patients with OLP. Results showed a mixed expression pattern with OLP variably resembling normal as well as tumour tissue. Based on our present and previous data it cannot be judged whether OLP lesions are at an increased risk of malignant development.
Journal of Oral Pathology & Medicine, 2007
Oral Oncology, 2008
Oral lichen planus (OLP) is a chronic inflammatory disease of unknown origin, showing little spon... more Oral lichen planus (OLP) is a chronic inflammatory disease of unknown origin, showing little spontaneous regression. WHO classifies OLP as a premalignant condition, however, the underlying mechanisms initiating development of cancer in OLP lesions are not understood. The p53 tumour suppressor plays an important role in many tumours, and an increased expression of p53 protein has been seen in OLP lesions. Recently it was shown that the human TP53 gene encodes at least nine different isoforms. Another member of the p53 family, p63, comprises six different isoforms and plays a crucial role in the formation of oral mucosa, salivary glands, teeth and skin. It has also been suggested that p63 is involved in development of squamous cell carcinoma of the head and neck (SCCHN). In contrast to p53, a decreased expression of p63 protein has been seen in OLP lesions. In this study, we mapped the expression of five novel p53 isoforms at RNA and protein levels in OLP and matched normal controls. In the same samples we also measured levels of p63 isoforms using quantitative RT-PCR. Results showed p53 to be expressed in all OLP lesions and normal tissues. The p53b and D133p53 isoforms were expressed in the majority of samples whereas the remaining three novel isoforms analysed were expressed in only a few samples. Levels of p63 isoforms were lower in OLP lesions compared with normal tissue, however, changes were not statistically significant.
Journal of Oral Pathology & Medicine, 2010
Lichen planus is a chronic inflammatory disease of mucosa and skin affecting approximately 1-2% o... more Lichen planus is a chronic inflammatory disease of mucosa and skin affecting approximately 1-2% of the adult population. Autoimmunity has been implicated in the etiology of this disease, and recently we detected antibodies directed against all six p63 isoforms in sera from 2 out of 20 patients diagnosed with oral lichen planus (OLP) using Western blot analysis. Here we have developed an ELISA method for screening sera for presence of autoantibodies directed against p63. Using the same sera as previously analysed, we show that the optical density ratios for sera from the two patients with known autoantibodies was considerably higher compared to mean optical density ratios for all samples as well as controls analysed. Applying this novel ELISA technique for screening of sera from an additional group of 46 patients with oral and/or genital or skin lichen and 43 matched controls, we detected another three patients with autoantibodies against the p63 proteins. These data are discussed together with the observation that all five patients with detectable p63 autoantibodies from our two studies had clinically severe disease symptoms.
Expression of p63, COX-2, EGFR and ß-catenin in smokers and patients with squamous cell carcinoma of the head and neck reveal variations in non-neoplastic tissue and no obvious changes in smokers
International Journal of Oncology
ABSTRACT
Genes involved in epithelial differentiation and development are differentially expressed in oral and genital lichen planus epithelium compared to normal epithelium
Acta dermato-venereologica, 2014
Lichen planus (LP) is a chronic mucocutaneous disease with unknown cause. Patients with LP often ... more Lichen planus (LP) is a chronic mucocutaneous disease with unknown cause. Patients with LP often have both oral and genital lesions, but these conditions are often considered as separate diseases and treated accordingly. To find out which genes are differently expressed in mucosal LP compared to normal mucosa and establish whether oral and genital LP are in fact the same disease, whole genome expression analysis was performed on epithelium from 13 patients diagnosed with oral and/or genital LP and normal controls. For confirmation of keratin 4 and corneodesmosin expression, quantitative reverse-transcription PCR and immunohistochemistry were used. Many genes involved in epithelial development and differentiation are differently expressed in epithelium from LP compared to normal epithelium. Several of the differentially expressed genes are common for oral and genital LP and the same biological processes are altered which supports the fact that oral and genital LP are manifestations o...
International journal of oncology, 2011
Global miRNA expression arrays were used for analysis of 836 miRNAs in formalin-fixed paraffin-em... more Global miRNA expression arrays were used for analysis of 836 miRNAs in formalin-fixed paraffin-embedded samples from 21 tongue cancer patients and 8 controls. Samples had been stored for one to eleven years. Results separated tumour samples from controls, however, the largest variation was correlated to sample storage time, detectable already after one year. With the use of a linear regression model we could adjust for the storage-dependent effect, leading to the identification of 54 differentially expressed miRNAs in tongue cancer, compared to 16 when using standard normalization, including up-regulation of a novel miRNA, miR-424.
The diverse oncogenic and tumour suppressor roles of p63 and p73 in cancer: a review by cancer site
Histology and histopathology, Jan 16, 2014
p63 and p73, the two other members of the p53 family, were identified almost 15 years ago. Here, ... more p63 and p73, the two other members of the p53 family, were identified almost 15 years ago. Here, we review their potential use for diagnosis, prognosis and prediction of response to therapy in various cancers. The two genes show distinct expression patterns in both normal and cancer tissues and each gene gives rise to multiple protein isoforms with different activities, including those with tumour-suppressor or oncogenic effects. Despite such complexity, some common themes emerge; p63 is commonly over-expressed as the ΔNp63 isoform and sometimes associated with TP63 amplification, whereas p73 is often reduced (by methylation or gene loss), or there is an increase in the ratio of ΔNp73 to TAp73. These generalisations do not apply universally; TAp63 is overexpressed in haematological malignancies, TP63 mis-sense mutations have been reported in squamous cancers and TP63 translocations occur in lymphomas and some lung adenocarcinomas. There are associations with disease progno...
Tubulin α-6 chain is a stably expressed reference gene in archival samples of normal oral tissue and oral squamous cell carcinoma
Experimental and therapeutic medicine, May 1, 2010
One of the most critical factors in gene expression studies using quantitative real-time PCR is t... more One of the most critical factors in gene expression studies using quantitative real-time PCR is the choice of reference gene. Many of the commonly used reference genes have been shown to vary during a number of biological processes as well as between tissues. It is therefore important to always verify the stability of the gene of choice for all new tissues and experimental conditions. Here, we used two publicly available computer software packages (GeNorm and NormFinder) to investigate the stability of eight potential reference genes in formalin-fixed paraffin-embedded (FFPE) samples from normal oral tissue of different origin as well as from oral squamous cell carcinomas. Both programs found the tubulin α-6 chain (TUBA6) and ribosomal protein S13 (RPS13) to have the most stable expression between malignant and non-malignant tissue. NormFinder also found TUBA6 to be the most stable gene when samples were grouped according to tissue origin. FFPE samples constitute a large research re...
Endogenous p63 acts as a survival factor for tumour cells of SCCHN origin
International journal of molecular medicine, 2005
The human p63 gene encodes a series of proteins that differ in their N- and/or C-terminal sequenc... more The human p63 gene encodes a series of proteins that differ in their N- and/or C-terminal sequences and have widely differing properties in promoting or repressing p53-related functions such as growth arrest and apoptosis. In addition, p63 has important roles in the maintenance and differentiation of epithelial cell populations. Squamous cell carcinomas of the head and neck (SCCHN) express high levels of DeltaNp63 and p63beta isoforms compared to normal tissue from the same patients, suggesting a role for these isoforms in the pathogenesis of this common human malignancy. Here, we explore the function of p63 in SCCHN cells by using small interfering RNA (siRNA) to silence the expression of different isoforms in two SCCHN cell lines, FaDu and SCC-25. Silencing results in statistically significant decreased survival for tumour cells when all p63 isoforms, the N-terminal truncated or the alpha isoforms are inhibited. No effect was observed on cell proliferation or on the expression of ...
Mutation research, Jan 2, 2004
The major adverse consequences of radiation exposures are attributed to DNA damage in irradiated ... more The major adverse consequences of radiation exposures are attributed to DNA damage in irradiated cells that has not been correctly restored by metabolic repair processes. However, the dogma that genetic alterations are restricted to directly irradiated cells has been challenged by observations in which effects of ionizing radiation arise in non-irradiated cells. These, so called, untargeted effects are demonstrated in cells that are the descendants of irradiated cells either directly or via media transfer (radiation-induced genomic instability) or in cells that have communicated with irradiated cells (radiation-induced bystander effects). Radiation-induced genomic instability is characterized by a number of delayed responses including chromosomal abnormalities, gene mutations and cell death. Bystander effects include increases or decreases in damage-inducible and stress-related proteins, increases or decreases in reactive oxygen and nitrogen species, cell death or cell proliferation...
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Papers by Philip J Coates