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With the aim to dissect the effect of adult height on head and neck cancer (HNC), we use the Mendelian randomization (MR) approach to test the association between genetic instruments for height and the risk of HNC. 599 single nucleotide polymorphisms (SNPs) were identified as genetic instruments for height, accounting for 16% of the phenotypic variation. Genetic data concerning HNC cases and controls were obtained from a genome-wide association study. Summary statistics for genetic association were used in complementary MR approaches: the weighted genetic risk score (GRS) and the inverse-variance weighted (IVW). MR-Egger regression was used for sensitivity analysis and pleiotropy evaluation. From the GRS analysis, one standard deviation (SD) higher height (6.9 cm; due to genetic predisposition across 599 SNPs) raised the risk for HNC (Odds ratio (OR), 1.14; 95% Confidence Interval (95%CI), 0.99–1.32). The association analyses with potential confounders revealed that the GRS was associated with tobacco smoking (OR = 0.80, 95% CI (0.69–0.93)). MR-Egger regression did not provide evidence of overall directional pleiotropy. Our study indicates that height is potentially associated with HNC risk. However, the reported risk could be underestimated since, at the genetic level, height emerged to be inversely associated with smoking.

Head and neck squamous cell carcinoma (HNSCC) is a widely prevalent cancer globally with high mortality and morbidity. We report here changes in the genomic landscape in the development of HNSCC from potentially premalignant lesions (PPOLS) to malignancy and lymph node metastases. Frequent likely pathological mutations are restricted to a relatively small set of genes includingTP53, CDKN2A,FBXW7,FAT1,NOTCH1andKMT2D; these arise early in tumour progression and are present in PPOLs withNOTCH1mutations restricted to cell lines from lesions that subsequently progressed to HNSCC. The most frequent genetic changes are of consistent somatic copy number alterations (SCNA). The earliest SCNAs involved deletions ofCSMD1(8p23.2),FHIT(3p14.2) andCDKN2A(9p21.3) together with gains of chromosome 20.CSMD1deletions or promoter hypermethylation were present in all of the immortal PPOLs and occurred at high frequency in the immortal HNSCC cell lines (promoter hypermethylation ~63%, hemizygous deletions ~75%, homozygous deletions ~18%). Forced expression ofCSMD1in the HNSCC cell line H103 showed significant suppression of proliferation (p=0.0053) and invasioninvitro(p=5.98X10−5) supporting a role forCSMD1inactivation in early head and neck carcinogenesis. In addition, knockdown ofCSMD1in theCSMD1-expressing BICR16 cell line showed significant stimulation of invasionin vitro(p=1.82 x 10−5) but not cell proliferation (p=0.239). HNSCC with and without nodal metastases showed some clear differences including high copy number gains ofCCND1, hsa-miR-548k andTP63in the metastases group. GISTIC peak SCNA regions showed significant enrichment (adj PLay SummaryCancers affecting the head and neck region are relatively common. A large percentage of these are of one particular type; these are generally detected late and are associated with poor prognosis. Early detection and treatment dramatically improve survival and reduces the damage associated with the cancer and its treatment. Cancers arise and progress because of changes in the genetic material of the cells. This study focused on identifying such changes in these cancers particularly in the early stages of development, which are not fully known. Identification of these changes is important in developing new treatments as well as markers of behaviour of cancers and also the early or ‘premalignant’ lesions. We used a well-characterised panel of cell lines generated from premalignant lesions as well as cancers, to identify mutations in genes, and an increase or decrease in number of copies of genes. We mapped new and previously identified changes in these cancers to specific stages in the development of these cancers and their spread. We additionally report here for the first time, alterations inCSMD1gene in early premalignant lesions; we further show that this is likely to result in increased ability of the cells to spread and possibly, multiply faster as well.

Oral squamous cell carcinoma (OSCC) is a highly aggressive cancer that is associated with poor 5-year patient survival. Disease treatment is further compounded by the difficulty in predicting pre-cancerous tissues that will progress to OSCC and the high recurrence rates following surgical resection. Here we have assessed expression of the oral epithelial markers E-cadherin, EMP1 and 5T4 and the pro-invasive N-cadherin proteins using fully characterised antibodies and quantitative immunofluorescence microscopy in normal tissue (NT), fibroepithelial polyp (FEP), low-grade dysplasia (LGD), high-grade dysplasia (HGD), T1 OSCC and T4 OSCC biopsies. Decreased E-cadherin expression was associated with FEP, LGD and HGD biopsies, demonstrating that loss of E-cadherin is an early event within abnormal epithelium and occurs in the absence of an E- to N-cadherin switch, the latter of which was only observed in T4 OSCC. Furthermore, loss of E-cadherin and EMP1 is an indicator of LGD (p = 0.0006) and loss of E-cadherin, EMP1 and 5T4 an indicator of HGD (p = 0.0006). Expression patterns of E-cadherin, EMP1 and N-cadherin could predict abnormal epithelium in LGD, HGD, T1 and T4 OSCC biopsies (z-value = 0 for all disease grades) and allowed classification of LGD (z = 1.47), HGD (z = 2.138), T1 (z = 1.05) and T4 OSCC (z = 1.49) biopsies. Therefore, these markers provide a useful means to predict abnormal epithelium in patient biopsies. Linear regression and coefficient of determination analysis revealed positive correlation with a NT>LGD>HGD disease transition but low correlation with a putative HGD>T1 OSCC>T4 OSCC disease transition. Furthermore, expression of E-cadherin, EMP1, 5T4 and N-cadherin in pathologically normal surgical safety margins of LGD, HGD and T1 OSCC patient biopsies revealed significant differences to NT and the use of safety margins or FEP as ‘normal tissue’ controls introduced Type II errors in all patient cohorts. This work forms the basis for further investigation of the role of E-cadherin loss in abnormal epithelium and in the development of automated analyses for use in cancer diagnostics.

Infiltrating lipomatosis of the face has been described as a congenital disorder in which mature lipocytes invade adjacent tissues in the facial region. The presentation is always unilateral with hypertrophy of hard and soft structures on the affected side of the face. We present a case of a 27-year-old female who reported with a complaint of recurrent unilateral facial swelling with history of two previous resections, the histopathology or details of these surgeries were not available. The patient underwent resection of tumour and the histopathology confirmed it to be infiltrating lipomatosis. The surgery resulted in a definite improvement in the facial asymmetry and the patient is being closely followed up with no evidence of recurrence. The pathogenesis of the condition is unclear, though it has been postulated that the condition is at one end of a spectrum of overgrowth syndromes with classic Proteus syndrome on the other extreme. Management of this condition involves resection of the tumour which in most cases is subtotal to reduce the risk of damage to facial nerve. There is a controversy regarding both timing and extent of resection in the literature and we think the subtotal resection of tumour in an adolescent or older patient can give good aesthetic outcome without compromising facial nerve function. However, the patients should be informed about high rate of recurrence and increase risk of complications with any subsequent surgery.

We report a rare genetic condition characterized by gingival hyperkeratosis with skin changes affecting the hands and feet. The patient presented with asymptomatic oral lesions and the diagnosis was reached by taking a full clinical history and biopsy tests. Palmoplantar keratosis can be a feature of a range of different syndromes and can be associated with periodontal destruction, benign oral keratosis or cancer of the oesophagus. It is important for dentists to be aware that clues to diagnosis can be gained from examination of the hands and feet, in addition to an oral examination, particularly in recognizing oral genetic disorders.To inform clinicians of both the intra-oral and extra-oral features of focal palmoplantar and gingival hyperkeratosis.

The present study attempted to assess the reasons behind the inter-observer variation in grading oral epithelial dysplasia (OED). Three oral pathologists and one general pathologist examined 68 histological slides of OED lesions of variable grade for scoring the presence of each individual characteristic of the architecture and cytology changes that were established by the 2005 WHO classification. The assigned features in each case were correlated with clinical outcomes to understand which features are more commonly associated with malignant transformation. Interestingly, for all individual characteristics, the pairwise inter-examiner and group kappa values ranged from poor to moderate. It appeared that for each characteristic separately there was much dissension. Despite these observations, comparing these data with that from our previous paper on the same slides showed that the inter-observer agreement on the degree of dysplasia either by using the new binary system of "low-risk" or "high-risk" or by using the 2005 WHO classification turned out to be better than the agreement on the individual characteristics of architecture and cytology changes. Certain features show significant association with the clinical outcomes. In the discussion, some explanations to help understanding the sources of variation in grading OED are put forward. In conclusion, grading dysplasia is not an exact science and pathologists are doing their best to reach optimal results. Improvement in the standard of the histopathology reporting of OED lesions could be achieved by consideration of several issues. Of these, there is need for a universal definition of the architectural and cytological features that are the basis of any OED grading process. A minimum dataset for reporting OED lesions should be set up. Also, the use of a consensus scoring process between two or more observers should be encouraged as this would improve inter-observer agreement.

Papillon-Lefévre syndrome is a rare, inherited, autosomal-recessive disease, characterized by palmoplantar keratosis and severe prepubertal periodontitis, leading to premature loss of all teeth. Papillon-Lefévre syndrome is caused by a mutation in the cathepsin C gene, resulting in complete loss of activity and subsequent failure to activate immune response proteins. Periodontitis in Papillon-Lefévre syndrome is thought to arise from failure to eliminate periodontal pathogens as a result of cathepsin C deficiency, although mechanistic pathways remain to be elucidated. The aim of this study was to characterize comprehensively neutrophil function in Papillon-Lefévre syndrome. Peripheral blood neutrophils were isolated from 5 patients with Papillon-Lefévre syndrome, alongside matched healthy control subjects. For directional chemotactic accuracy, neutrophils were exposed to the chemoattractants MIP-1α and fMLP and tracked by real-time videomicroscopy. Reactive oxygen species generation was measured by chemiluminescence. Neutrophil extracellular trap formation was assayed fluorometrically, and proinflammatory cytokine release was measured following overnight culture of neutrophils with relevant stimuli. Neutrophil serine protease deficiencies resulted in a reduced ability of neutrophils to chemotax efficiently and an inability to generate neutrophil extracellular traps. Neutrophil extracellular trap-bound proteins were also absent in Papillon-Lefévre syndrome, and Papillon-Lefévre syndrome neutrophils released higher levels of proinflammatory cytokines in unstimulated and stimulated conditions, and plasma cytokines were elevated. Notably, neutrophil chemoattractants MIP-1α and CXCL8 were elevated in Papillon-Lefévre syndrome neutrophils, as was reactive oxygen species formation. We propose that relentless recruitment and accumulation of hyperactive/reactive neutrophils (cytokines, reactive oxygen species) with increased tissue transit times into periodontal tissues, alongside a reduced antimicrobial capacity, create a locally destructive chronic inflammatory cycle in Papillon-Lefévre syndrome.

The aim of this paper is to assess the reproducibility of a novel binary grading system (high/low risk) of oral epithelial dysplasia and to compare it with the WHO classification 2005. The accuracy of the new system for predicting malignant transformation was also assessed. Ninety-six consecutive oral epithelial dysplasia biopsies with known clinical outcomes were retrieved from the Oral Pathology archives. A pilot study was conducted on 28 cases to determine the process of classification. Four observers then reviewed the same set of H&E stained slides of 68 oral dysplastic lesions using the two grading systems blinded to the clinical outcomes. The overall inter-observer unweighted and weighted kappa agreements for the WHO grading system were Ks = 0.22 (95% CI: 0.11-0.35), Kw = 0.63 (95% CI: 0.42-0.78), respectively, versus K = 0.50 (95% CI: 0.35-0.67) for the new binary system. Interestingly, all pathologists showed satisfactory agreement on the distinction of mild dysplasia from severe dysplasia and from carcinoma in situ using the new WHO classification. However, assessment of moderate dysplasia remains problematic. The sensitivity and specificity of the new binary grading system for predicting malignant transformation in oral epithelial dysplasia were 85% and 80%, respectively and the accuracy was 82%. The new binary grading system complemented the WHO Classification 2005 and may have merit in helping clinicians to make critical clinical decisions particularly for the cases of moderate dysplasia. Histological grading of dysplasia using established criteria is a reproducible prognosticator in oral epithelial dysplasia. Furthermore, the present study showed that more consensus scoring on either the degree of dysplasia, assessment of risk or the presence of each morphological characteristic by a panel should be encouraged.

OBJECTIVE: To survey two broad areas of oral cancer awareness and management of patients at risk of oral cancer by specialists in oral surgery, oral medicine, surgical dentistry and general dental practitioners (GDPs) in the UK. The first of these included knowledge and awareness of aetiological factors, changing patterns of disease, and screening/detection programmes including their effectiveness. The second included oral cancer detection methods, advice on avoidance of high-risk activity and self-examination, and referral pattern of GDPs. DESIGN AND METHOD: A pretested, 44-item questionnaire, a covering letter, a brief outline of the research protocol and return, stamped envelope were mailed in March 2003. A sample of 200 GDPs whose names were obtained from the General Dental Council's main list and 305 dental specialist names obtained from specialist's list in surgical dentistry, oral medicine and oral surgery were selected randomly. Information on oral cancer awareness and practice, screening practice and education was obtained. RESULTS: The response rate was 66.9%. The knowledge of the dental specialists was consistent with that in reports of current aetiological studies on oral cancer. However there were gaps in the GDP's knowledge and ascertainment of oral cancer risk factors. Over 70% of the dental specialists provided counselling advice on the risks of tobacco and alcohol habits compared with 41.2% of GDPs. More GDPs (52.4%) than specialists (35.4%) believed that oral cancer screening on a national basis would be effective in decreasing the mortality of oral cancer. Over 95% of all respondents used a visual examination for oral cancer screening and 89.9% of all respondents strongly believed that visual screening is effective in the early detection of oral cancer. CONCLUSION: The results showed that GDPs had knowledge gaps in their awareness of oral cancer risk factors and the application of preventive measures. Most dental health providers in the UK perform visual screening of the oral mucosa for their patients. Opinion was equivocal as to whether a nationally based screening programme similar to cervical cancer would be effective in improving the mortality and morbidity of oral cancer.

Worldwide, oral cancer has one of the lowest survival rates. It is well recognized that survival rates are improved if the disease is treated in its early stages. The aim of this study was to assess the effectiveness of screening methods in decreasing the mortality of oral cancer. A systematic review on the effectiveness of oral cancer screening was performed using all publications in MEDLINE, CANCERLIT, EMBASE, and Cochrane CCTR between 1966 and September 2002. The evidence was evaluated using the standardized methodology of the Cochrane Collaboration. The search strategy revealed 1,389 citations. From these, 100 potentially relevant articles were selected for review. However, only one randomized controlled study using visual examination as the method for screening fulfilled the selection criteria. Given the limitation of evidence and the potential methodological weakness in the included study, it is valid to say that there is no evidence to recommend inclusion or exclusion of screening programs for oral cancer using visual examination in the general population. In addition, no robust evidence exists that indicates whether other screening methods including toluidine blue, fluorescence imaging, or brush biopsy are either beneficial or harmful. Further high-quality studies to assess the efficacy and effectiveness of screening are required. Additional investigations aimed at elucidating the natural history of oral cancer and evaluating the effectiveness of prevention and opportunistic screening in high-risk groups are needed. A greater understanding of the genetic basis of oral cancer is an essential prerequisite to the development of molecular markers for screening.

Allelic imbalance on chromosome arm 8p is common in head and neck squamous cell carcinoma (HNSCC). DLC1, a tumour suppressor gene inactivated in liver carcinogenesis and encoding a Rho GTPase activating protein (RhoGAP) maps to one of the deleted regions (8p21.3-22). In order to determine whether inactivation of DLC1 is involved in HNSCC, we have screened tumour cell lines for DLC1 mutations and expression. Pathological mutations were not identified in any of the 17 cell lines tested. Seven polymorphisms were identified; 13 of the 17 of cell lines were homozygous for all seven polymorphisms compared to only 2 of 17 controls suggesting a loss of heterozygosity in a majority of the cell lines. DLC1 expression was observed in all 11 HNSCC cell lines tested, thus excluding the possibility of transcriptional silencing of DLC1 by promoter hypermethylation. Overall, our data suggest that hemizygous deletions of the DLC1 locus are frequent in HNSCCs but this gene is unlikely to be primary target for inactivation on this chromosomal arm.

Hypoxia in tumours of the oral cavity has not been extensively investigated with regard to clinical outcome and prognosis. The expression of the facilitative glucose transporter, Glut-1, has been shown to be related to hypoxia in tumours at other sites. The aim of the present study was to investigate the relationship between Glut-1 expression and clinical outcome in a series of oral squamous cell carcinomas. A retrospective series of 54 cases of oral squamous cell carcinomas with known clinical outcome and treated by one surgeon over a period of 6 years was used in the study. A representative section from each case was stained immunohistochemically with an antibody against Glut-1. The stained sections were then assessed independently by two observers using a semi-quantitative method. The relationship between these results and the clinical outcomes of local recurrence, regional lymph-node metastasis and disease-free survival were examined. Glut-1 staining was observed in most of the tissue specimens and all of the few sections with demonstrably necrotic areas histologically. Some showed more prominent staining in the epithelial islands of the tumour than others. However, the intensity of staining was variable. There was a significant relationship between those tumours which demonstrated intense staining and recurrence overall (chi(2)=6.18, P=0.032). This relationship was strongest in relation to regional lymph-node recurrence (chi(2)=10.19, P=0.005). A significant relationship between disease-related death and intense Glut-1 staining was also observed (chi(2)=11.67, P=0.002). In conclusion, the results of this study indicate a relationship between Glut-1 expression and disease progression of oral cancer and could indicate a need for neoadjuvant chemoradiotherapy for those tumours demonstrating intense Glut-1 expression.

We have previously reported that loss-of-function mutations in the cathepsin C gene (CTSC) result in Papillon Lefevre syndrome, an autosomal recessive condition characterized by palmoplantar keratosis and early,onset, severe periodontitis. Others have also reported CTSC mutations in patients with severe prepubertal periodontitis, but without any skin manifestations. The possible role of CTSC variants in more common types of non-mendelian, early-onset, severe periodontitis ("aggressive periodontitis") has not been investigated. In this study, we have investigated the role of CTSC in all three conditions. We demonstrate that PLS is genetically homogeneous and the mutation spectrum that includes three novel mutations (c.386T>A/p. V129E, c.935A>G/p.Q312R, and c.1235A>G/p.Y412C) in 21 PLS families (including eight from our previous study) provides an insight into structure-function relationships of CTSC. Our data also suggest that a complete loss-of-function appears to be necessary for the manifestation of the phenotype, making it unlikely that weak CTSC mutations are a cause of aggressive periodontitis. This was confirmed by analyses of the CTSC activity in 30 subjects with aggressive periodontitis and age-sex matched controls, which demonstrated that there was no significant difference between these two groups (1,728.7 +/- SD 576.8 mu moles/mg/min vs. 1,678.7 +/- SD 527.2 mu moles/mg/min, respectively, p = 0.73). CTSC mutations were detected in only one of two families with prepubertal periodontitis; these did not form a separate functional class with respect to those observed in classical PLS. The affected individuals in the other prepubertal periodontitis family not only lacked CTSC mutations, but in addition did not share the haplotypes at the CTSC locus. These data suggest that prepubertal periodontitis is a genetically heterogeneous disease that, in some families, just represents a partially penetrant PLS. (C) 2004 Wiley-Liss, Inc.

BACKGROUND: We have previously described a weighted index for determining the diagnostic significance of dento-osseous changes observed on dental panoramic radiographs (DPRs) in individuals at 50% risk of inheriting Familial Adenomatous Polyposis (FAP). A diagnostic test based on this index (Dental Panoramic Radiograph Score, DPRS) was shown to have a sensitivity of 69% and specificity of 100%. OBJECTIVES: To evaluate the validity of the diagnostic test in an independent sample of individuals at 50% risk of inheriting FAP. DESIGN: A retrospective assessment of DPRs in individuals at 50% risk of inheriting FAP. SUBJECTS AND METHODS: A final year dental student assessed blindly and independently, DPRs from an independent sample (n = 119) of affected (n = 26), unaffected (n = 78) and clinically low risk individuals (n = 15). This revealed a sensitivity and specificity of 62 and 97% respectively which is in close agreement with results of the previous study. The dental student's training in assessing DPRs was previously tested using radiographs from 81 individuals from our original study. Weighted Kappa statistics were used to test for agreement. A kappa score of 0.82 (95% confidence interval 0.70-0.93) indicated almost perfect agreement. MAIN OUTCOME: The DPRS is a reproducible and valid index for assessing the diagnostic significance of dentoosseous changes, in individuals at 50% risk of FAP, even in relatively inexperienced hands.

This paper examines the genetic defects associated with inherited cancer syndromes and their relevance to oral cancer. Tumour suppressor genes are now thought of as either gatekeepers or caretakers according to whether they control cell growth directly by inhibiting cell proliferation and/or promoting cell death (gatekeepers) or whether they maintain the integrity of the genome by DNA repair mechanisms (caretakers). In disorders such as xeroderma pigmentosum, ataxia telangiectasia, Bloom syndrome and Fanconi's anaemia, where there are defective caretaker genes, there is an increased incidence of second primary malignancies, including oral cancer. By contrast, with the exception of Li Fraumeni syndrome, abnormalities of gatekeeper genes do not predispose to oral cancer. Not only do Li Fraumeni patients develop second primary malignancies, but defects of the p53 pathway (p53 mutation, MDM2 over-expression, CDKN2A deletion) appear to be a ubiquitous feature of sporadic oral cancer as it occurs in the West. The findings suggest that genetic instability is of fundamental importance in the pathogenesis of oral cancer.

One of the most important components of G1 checkpoint is the retinoblastoma protein (pRB110). The activity of pRB is regulated by its phosphorylation, which is mediated by genes such as cyclin D1 and p16/MTS1. All three genes have been shown to be commonly altered in human malignancies. We have screened a panel of 26 oral squamous cell carcinomas (OSCC), nine premalignant and three normal oral tissue samples as well as eight established OSCC cell lines for mutations in the p16/MTS1 gene. The expression of p16/MTS1, cyclin D1 and pRB110 was also studied in the same panel. We have found p16/MTS1 gene alterations in 5/26 (19%) primary tumours and 6/8 (75%) cell lines. Two primary tumours and five OSCC cell lines had p16/MTS1 point mutations and another three primary and one OSCC cell line contained partial gene deletions. Six of seven p16/MTS1 point mutations resulted in termination codons and the remaining mutation caused a frameshift. Western blot analysis showed absence of p16/MTS1 expression in 18/26 (69%) OSCC, 7/9 (78%) premalignant lesions and 8/8 cell lines. One cell line, H314, contained a frameshift mutation possibly resulting in a truncated p16/MTS1 protein. pRB was detected in 14/25 (56%) of OSCC but only 11/14 (78%) of these contained all or some hypophosphorylated (active) pRB. In premalignant samples, 6/8 (75%) displayed pRB, and all three normal samples and eight cell lines analysed contained RB protein. p16/MTS1 protein was undetectable in 10/11 (91%) OSCCs with positive pRB. Overexpression of cyclin D1 was observed in 9/22 (41%) OSCC, 3/9 (33%) premalignant and 8/8 (100%) of OSCC cell lines. Our data suggest p16/MTS1 mutations and loss of expression to be very common in oral cancer cell lines and less frequent in primary OSCC tumours. A different pattern of p16/MTS1 mutations was observed in OSCC compared to other cancers with all the detected p16/MTS1 mutations resulting in premature termination codons or a frameshift. The RB protein was expressed in about half (44%) of OSCCs and its expression inversely correlated with p16/MTS1 expression. In conclusion, we show that abnormalities of the RB pathway are a common mechanism of oral carcinogenesis. © 1999 Cancer Research Campaign

Frequent loss of heterozygosity on chromosome 8p in a variety of human malignancies, including head and neck cancers, has suggested the presence of a tumor suppressor gene (or genes) associated with the pathogenesis of these cancers. To test the role of genetic alterations at 8p23 in oral carcinogenesis, we studied 51 squamous cell carcinomas of the head and neck and 29 oral squamous cell carcinoma cell lines for allelic loss using 7 microsatellite markers spanning approximately 5 cM of chromosome band 8p23. Twenty-three of 51 tumors (45%) and 23 of 29 cell lines (79%) showed allelic loss at 1 or more loci. Three cell lines showed homozygous deletion of loci within a 3 cM region defined by the markers D8S1781 and D8S262. Our results suggest that a tumor suppressor gene (or genes) is located in 8p23 and is associated with the development and/or progression of oral carcinomas.

Patients who present with unilateral vestibular schwannomas either at a young age or with additional features of type 2 neurofibromatosis (NF2) are at risk of developing bilateral disease and transmitting a risk of neurogenic tumours to their offspring. We have identified 15 patients from a series of 537 with unilateral vestibular schwannomas who also had one or more of the following: other tumours (10/15), features of NF2 (3/15), or a family history of neurogenic tumours (5/15). No germline NF2 mutations were detected and in 7/9 cases where tumour material was available for analysis a germline mutation in the NF2 gene has been excluded. Although a possibility of gonosomal mosaicism still exists, exclusion tests for the offspring are now possible. We suggest a general strategy, based on analysis of tumour DNA, for distinguishing sporadic and familial cases of tumours caused by two hit mechanisms. Application of this strategy suggests that most instances of unilateral vestibular schwannoma which do not fulfil criteria for NF2 represent chance occurrences.

Deletions on chromosome arm 8p, as defined by allelic imbalance, are a frequent event in many different types of malignant tumors, including those of the head and neck. These regions are thought to harbor tumor suppressor genes. In order to define a high-density deletion map of this chromosomal arm in oral and oropharyngeal squamous cell carcinomas, we have tested for allelic imbalance in 35 such tumors with 22 short tandem-repeat polymorphisms. Overall, 21 (60%) of the 35 tumors showed allelic imbalance at one or more loci on chromosome arm 8p. Interstitial deletions defined three discrete areas of deletion: at 8p23, 8p22, and 8p12-p21. Tumors of TNM stages II-IV showed a significantly higher frequency of allelic imbalance on 8p than did TNM stage I tumors. Our data suggest that there are least three tumor suppressor loci on chromosome arm 8p that may be implicated in oral carcinogenesis. Furthermore, inactivation of such genes may be associated with high-grade tumors.

Background We have previously reported oxidative and fatty acids disturbances in one Papillon–Lefevre syndrome (PLS) family. This Mendelian condition characterized by palmar plantar keratosis and severe aggressive periodontitis, is caused by mutations in the cathepsin C (CTSC) gene. In this study, we have analysed two further unrelated PLS families to confirm this association. Methods Mutations were identified by direct sequencing of CTSC. Biochemical analyses were performed in probands and their relatives in order to determine plasma levels of vitamin E, CoQ10, lipid hydroperoxides (HP) and fatty acid patterns. Results Pathogenic CTSC mutations were identified in both families including a new mutation (c504C>G). Both probands showed low levels of vitamin E and CoQ10, and high levels of lipid HP, and also very low levels of docohexaenoic acid. Conclusions The previously reported oxidative and fatty acids disturbances were confirmed as a feature of this condition in two further families. There are low levels of antioxidant markers and high levels of oxidative markers, in addition of low levels of some anti-inflammatory fatty acids in persons suffering PLS and some of their relatives.

Human papillomavirus (HPV) is causally implicated in a subset of cancers of the upper aero-digestive tract (UADT). Methods Associations between type-specific HPV antibodies were examined among 1496 UADT cancer case subjects and 1425 control subjects by estimating odds ratios (ORs) in logistic regression analyses adjusted for potential confounders. The agreement between serology and tumor markers of HPV infection, including presence of HPV DNA and p16 expression, were examined in a subset of tumors. Results HPV16 L1 seropositivity was associated with increased risk of oral cavity and oropharyngeal cancer (OR = 1.94, 95% confidence interval [CI] = 1.03 to 3.65; OR = 8.60, 95% CI = 5.21 to 14.20, respectively). HPV16 E6 antibodies were present in 30.2% of oropharyngeal case subjects and only 0.8% of control subjects (OR = 132.0, 95% CI = 65.29 to 266.86). Combined seropositivity to HPV16 E6 and E7 was rare (n = 1 of 1425 control subjects). An agreement of 67% was observed between HPV16 E6 serology and the corresponding presence of an HPV-related cancer: four of six HPV DNA-positive/p16-overexpressing tumors were HPV16 E6 antibody positive. An HPV16 independent association was observed for HPV18 and oropharyngeal cancer (OR = 8.14, 95% CI = 2.21 to 29.99 for HPV18 E6 seropositivity) and HPV6 and laryngeal cancer (OR = 3.25, 95% CI = 1.46 to 7.24 for HPV6 E7 seropositivity). Conclusions These results confirm an important role for HPV16 infection in oropharyngeal cancer. HPV16 E6 antibodies are strongly associated with HPV16-related oropharyngeal cancers. Continuing efforts are needed to consider both HPV serology and p16 staining as biomarkers relevant to the etiology and natural history of HPV16-related oropharyngeal tumors. These results also support a marginal role for HPV18 in oropharyngeal cancer and HPV6 in laryngeal cancer

Johansson, Mattias Roberts, Angus Chen, Dan Li, Yaoyong Delahaye-Sourdeix, Manon Aswani, Niraj Greenwood, Mark A Benhamou, Simone Lagiou, Pagona Holcatova, Ivana Richiardi, Lorenzo Kjaerheim, Kristina Agudo, Antonio Castellsague, Xavier Macfarlane, Tatiana V Barzan, Luigi Canova, Cristina Thakker, Nalin S Conway, David I Znaor, Ariana Healy, Claire M Ahrens, Wolfgang Zaridze, David Szeszenia-Dabrowska, Neonilia Lissowska, Jolanta Fabianova, Eleonora Mates, Ioan Nicolae Bencko, Vladimir Foretova, Lenka Janout, Vladimir Curado, Maria Paula Koifman, Sergio Menezes, Ana Wunsch-Filho, Victor Eluf-Neto, Jose Boffetta, Paolo Franceschi, Silvia Herrero, Rolando Fernandez Garrote, Leticia Talamini, Renato Boccia, Stefania Galan, Pilar Vatten, Lars Thomson, Peter Zelenika, Diana Lathrop, Mark Byrnes, Graham Cunningham, Hamish Brennan, Paul Wakefield, Jon McKay, James D eng 1R03DE020116/DE/NIDCR NIH HHS/ R01 CA092039 05/CA/NCI NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't 2012/06/05 06:00 PLoS One. 2012;7(5):e36888. doi: 10.1371/journal.pone.0036888. Epub 2012 May 25.; International audience; BACKGROUND: Genome-wide association studies (GWAS) require large sample sizes to obtain adequate statistical power, but it may be possible to increase the power by incorporating complementary data. In this study we investigated the feasibility of automatically retrieving information from the medical literature and leveraging this information in GWAS. METHODS: We developed a method that searches through PubMed abstracts for pre-assigned keywords and key concepts, and uses this information to assign prior probabilities of association for each single nucleotide polymorphism (SNP) with the phenotype of interest―the Adjusting Association Priors with Text (AdAPT) method. Association results from a GWAS can subsequently be ranked in the context of these priors using the Bayes False Discovery Probability (BFDP) framework. We initially tested AdAPT by comparing rankings of known susceptibility alleles in a previous lung cancer GWAS, and subsequently applied it in a two-phase GWAS of oral cancer. RESULTS: Known lung cancer susceptibility SNPs were consistently ranked higher by AdAPT BFDPs than by p-values. In the oral cancer GWAS, we sought to replicate the top five SNPs as ranked by AdAPT BFDPs, of which rs991316, located in the ADH gene region of 4q23, displayed a statistically significant association with oral cancer risk in the replication phase (per-rare-allele log additive p-value [p(trend)] = 2.5x10(-3)). The combined OR for having one additional rare allele was 0.83 (95% CI: 0.76-0.90), and this association was independent of previously identified susceptibility SNPs that are associated with overall UADT cancer in this gene region. We also investigated if rs991316 was associated with other cancers of the upper aerodigestive tract (UADT), but no additional association signal was found. CONCLUSION: This study highlights the potential utility of systematically incorporating prior knowledge from the medical literature in genome-wide analyses using the AdAPT methodology. AdAPT is available online (url: http://services.gate.ac.uk/lld/gwas/service/config).

Background The study aimed to investigate the role of medical history (skin warts, Candida albicans, herpetic lesions, heartburn, regurgitation) and medication use (for heartburn; for regurgitation; aspirin) in the aetiology of upper aerodigestive tract (UADT) cancer. Methods A multicentre (10 European countries) case–control study [Alcohol-Related CAncers and GEnetic susceptibility (ARCAGE) project]. Results There were 1779 cases of UADT cancer and 1993 controls. History of warts or C. albicans infection was associated with a reduced risk [odds ratio (OR) 0.80, 95% confidence interval (CI) 0.68–0.94 and OR 0.73, 95% CI 0.60–0.89, respectively] but there was no association with herpetic lesions, heartburn, regurgitation or medication for related symptoms. Regurgitation was associated with an increased risk for cancer of the oesophagus (OR 1.47, 95% CI 0.98–2.21). Regular aspirin use was not associated with risk of UADT cancer overall but was associated with a reduced risk for cancer of oesophagus (OR 0.51, 95% CI 0.28–0.96), hypopharynx (OR 0.53, 95% CI 0.28–1.02) and larynx (OR 0.74, 95% CI 0.54–1.01). Conclusions A history of some infections appears to be a marker for decreased risk of UADT cancer. The role of medical history and medication use varied by UADT subsites with aspirin use associated with a decreased risk of oesophageal cancer and suggestive of a decreased risk of hypopharyngeal and laryngeal cancers.

Background Neurofibromatosis type 1 (NF1) affects 1 in 2500 people, and 15% of these may develop an optic pathway glioma (OPG). OPGs behave differently in NF1, and, given their frequency, surveillance is important. However, this is difficult because of the additional complications these patients may have, such as learning difficulties. Management is also different given that NF1 results from loss of function of tumour suppressor gene. A genotype–phenotype correlation may help to determine who is at risk of developing these tumours, aid focused screening, and shed light on response to treatments. Methods As part of a long-term follow-up study of patients with NF1 OPGs, the authors assessed genotype–phenotype correlation. Fluorescein in situ hybridisation was performed to identify large deletions, and then a full gene screen for mutations, by denaturing high-performance liquid chromatography. Results 80 patients with NF1 OPGs were identified, and molecular analyses were performed in a subset of 29. A clustering of pathogenic changes in the 5′ tertile of the gene was found. The authors combined these results with those for another two NF1 OPG cohorts and collectively found the same trend. When compared with a control population of NF1 patients without an OPG, the OR of a mutation being present in the 5′ tertile was 6.05 (p=0.003) in the NF1 OPG combined cohorts. Conclusion It is possible that genotype is a significant determinant of the risk of development of OPGs in NF1.

Background: Sequence variants located at 15q25 have been associated with lung cancer and propensity to smoke. We recently reported an association between rs16969968 and risk of upper aerodigestive tract (UADT) cancers (oral cavity, oropharynx, hypopharynx, larynx, and esophagus) in women (OR = 1.24, P = 0.003) with little effect in men (OR = 1.04, P = 0.35). Methods: In a coordinated genotyping study within the International Head and Neck Cancer Epidemiology (INHANCE) consortium, we have sought to replicate these findings in an additional 4,604 cases and 6,239 controls from 10 independent UADT cancer case–control studies. Results: rs16969968 was again associated with UADT cancers in women (OR = 1.21, 95% CI = 1.08–1.36, P = 0.001) and a similar lack of observed effect in men [OR = 1.02, 95% CI = 0.95–1.09, P = 0.66; P-heterogeneity (Phet) = 0.01]. In a pooled analysis of the original and current studies, totaling 8,572 UADT cancer cases and 11,558 controls, the association was observed among females (OR = 1.22, 95% CI = 1.12–1.34, P = 7 × 10−6) but not males (OR = 1.02, 95% CI = 0.97–1.08, P = 0.35; Phet = 6 × 10−4). There was little evidence for a sex difference in the association between this variant and cigarettes smoked per day, with male and female rs16969968 variant carriers smoking approximately the same amount more in the 11,991 ever smokers in the pooled analysis of the 14 studies (Phet = 0.86). Conclusions: This study has confirmed a sex difference in the association between the 15q25 variant rs16969968 and UADT cancers. Impact: Further research is warranted to elucidate the mechanisms underlying these observations. Cancer Epidemiol Biomarkers Prev; 20(4); 658–64. ©2011 AACR.

CUB and SUSHI multiple domain protein 1 (CSMD1) is a candidate tumour suppressor gene that maps to chromosome 8p23, a region deleted in many tumour types including 50% of breast cancers. CSMD1 has homologies to proteins implicated in carcinogenesis. We aimed to study the expression pattern of the CSMD1 protein and evaluate its prognostic importance in invasive ductal carcinoma (IDC). An anti-CSMD1 antibody was developed and validated. The expression pattern of CSMD1 in normal breast and IDC samples was investigated by immunohistochemistry in 275 patients. Univariate and multivariate Cox regression analyses were performed. In normal breast duct epithelial cells, luminal, membranous and cytoplasmic CSMD1 staining was identified. Reduced expression of CSMD1 was detected in 79/275 (28.7%) of IDC cases. Low CSMD1 expression was significantly associated with high tumour grade (P = 0.003). CSMD1 expression was associated with overall survival (OS; HR = 0.607, 95%CI: 0.4-0.91, P = 0.018) but not with disease-free survival (DFS; HR = 0.81, 95%CI: 0.46-1.43, P = 0.48). Multivariate analysis showed that CSMD1, together with Nottingham Prognostic Index, was considered an independent predictor of OS (HR = 0.607, 95%CI: 0.4-0.91, P = 0.018) but not DFS (HR = 0.84, 95%CI: 0.46-1.5, P = 0.573). Reduction of CSMD1 expression was significantly associated with high tumour grade and decreased OS. Therefore, our results support the idea that CSMD1 is a tumour suppressor gene and suggest its possible use as a new prognostic biomarker. The membrane expression pattern of CSMD1 suggests that it may be a receptor or co-receptor involved in the process of signal transduction. © Springer Science+Business Media, LLC. 2009.

The reasons for an increasing incidence of oral cancer, particularly amongst younger persons is unclear. It has been hypothesised either to be a result of an increase in exposure to known risk factors amongst certain groups in the community, or to be due to new aetiological agents. Prior to conducting large expensive population-based studies, it seems appropriate to conduct initial smaller-scale surveys to assess evidence for each of these two hypotheses. This survey of young persons with oral cancer suggest that most are exposed to traditional risk factors of tobacco smoking, drinking alcohol and a low consumption of fruit and vegetables.

The association of mucocutaneous lichen planus and chronic liver disease is widely recognized. The hepatitis B and C viruses have been implicated as being important in this association, although their exact role remains unclear. Recently, lichenoid lesions of the skin after a hepatitis B vaccination have also been reported. In this case, a woman of Southeast Asian origin had lichenoid lesions affecting the oral mucous membranes develop after she was vaccinated against hepatitis B. The lesions appeared 3 weeks after the administration of the third dose of the vaccine and persisted for about 1 year. As the use of the hepatitis B vaccine becomes more widespread, more such cases can be expected to be encountered.

Matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry (IMS) is a recently developed technique that generates molecular profiles usually of peptide and protein signals directly from the surface of thin tissue sections and can be coupled with automation to generate two-dimensional ion density maps. This allows specific information to be obtained on the relative abundance and spatial distribution of the analytes of interest. The technique has potential for application in many diseases including cancer with respect to elucidating the molecular pathology and identifying potential biomarkers. In this proof-of-principle study we have evaluated inkjet printing of the sinapinic acid matrix used for MALDI-IMS directly onto the surface of human oral squamous cell carcinoma biopsy specimens. This MS profiling technique produced reproducible informative chemical images for clinical pathology. Analysis of the resulting protein profiles of highly expressed protein in squamous cell carcinoma of the tongue reveals spectral features at approximately 4500 and approximately 8360 Da.

The release of active pharmaceutical ingredients (APIs) into the environment is an ecologically important topic for study because, whilst APIs have been designed to have a wide range of biological properties for the target of interest (usually in man), little information on potential ecological risks is currently available regarding their effects on the organisms that inhabit the environment. In this study, the algae Micrasterias hardyi was exposed to propranolol, metoprolol (beta-adrenergic receptor agonist drugs) and mefenamic acid (a non steroidal anti-inflammatory drug), at concentrations ranging between 0.002-0.2 mM. Initial studies showed that Fourier transform infrared (FT-IR) spectroscopy on algal homogenates illustrated that all three APIs had a quantitative effect on the metabolism of the organisms and it was possible to estimate the level of API exposure from the FT-IR metabolic fingerprints using partial least squares (PLS) regression. From the inspection of the PLS loadings matrices it was possible to elucidate that all drugs caused effects on protein and lipid levels. Most strikingly propranolol had significant effects on the lipid components of the cell. These were dramatically reduced possibly as a consequence of loss of membrane integrity. In order to investigate this further, FT-IR microspectroscopy was used to generate detailed metabolic fingerprinting maps. These chemical maps revealed that all the drugs had a dramatic effect on the distribution of various chemical species throughout the algae, and that all drugs had an affect on protein and lipid levels. In particular, as noted in the PLS analyses for propranolol treated cells, the lipid complement found in the lipid storage areas in the processes of M. hardyi was greatly reduced. This illustrates the power of spatial metabolic fingerprinting for investigating abiotic stresses on complex biological species.

Delahaye-Sourdeix, Manon Oliver, Javier Timofeeva, Maria N Gaborieau, Valerie Johansson, Mattias Chabrier, Amelie Wozniak, Magdalena B Brenner, Darren R Vallee, Maxime P Anantharaman, Devasena Lagiou, Pagona Holcatova, Ivana Richiardi, Lorenzo Kjaerheim, Kristina Agudo, Antonio Castellsague, Xavier Macfarlane, Tatiana V Barzan, Luigi Canova, Cristina Thakker, Nalin S Conway, David I Znaor, Ariana Healy, Claire M Ahrens, Wolfgang Zaridze, David Szeszenia-Dabrowska, Neonilia Lissowska, Jolanta Fabianova, Eleonora Mates, Ioan Nicolae Bencko, Vladimir Foretova, Lenka Janout, Vladimir Curado, Maria Paula Koifman, Sergio Menezes, Ana Wunsch-Filho, Victor Eluf-Neto, Jose Boffetta, Paolo Garrote, Leticia Fernandez Serraino, Diego Lener, Marcin Jaworowska, Ewa Lubinski, Jan Boccia, Stefania Rajkumar, Thangarajan Samant, Tanuja A Mahimkar, Manoj B Matsuo, Keitaro Franceschi, Silvia Byrnes, Graham Brennan, Paul McKay, James D eng 1R03DE020116/DE/NIDCR NIH HHS/ R01 CA092039 05/05S1/CA/NCI NIH HHS/ Research Support, N.I.H., Extramural 2015/03/21 06:00 PLoS One. 2015 Mar 20;10(3):e0117639. doi: 10.1371/journal.pone.0117639. eCollection 2015.; International audience; Genetic variants located within the 12p13.33/RAD52 locus have been associated with lung squamous cell carcinoma (LUSC). Here, within 5,947 UADT cancers and 7,789 controls from 9 different studies, we found rs10849605, a common intronic variant in RAD52, to be also associated with upper aerodigestive tract (UADT) squamous cell carcinoma cases (OR = 1.09, 95% CI: 1.04-1.15, p = 6x10(-4)). We additionally identified rs10849605 as a RAD52 cis-eQTL inUADT(p = 1x10(-3)) and LUSC (p = 9x10(-4)) tumours, with the UADT/LUSC risk allele correlated with increased RAD52 expression levels. The 12p13.33 locus, encompassing rs10849605/RAD52, was identified as a significant somatic focal copy number amplification in UADT(n = 374, q-value = 0.075) and LUSC (n = 464, q-value = 0.007) tumors and correlated with higher RAD52 tumor expression levels (p = 6x10(-48) and p = 3x10(-29) in UADT and LUSC, respectively). In combination, these results implicate increased RAD52 expression in both genetic susceptibility and tumorigenesis of UADT and LUSC tumors.

Purpose: Vaults are multi-subunit structures that may be involved in nucleo-cytoplasmic transport, with the major vault protein (MVP or lung resistance-related protein [LRP]) being the main component. The MVP gene is located on chromosome 16 close to the multidrug resistance-associated protein and protein kinase c- genes. The role of MVP in cancer drug resistance has been demonstrated in various cell lines as well as in ovarian carcinomas and acute myeloid leukemia, but nothing is known about its possible role in radiation resistance. Our aim was to examine this in head-and-neck squamous cell carcinoma (HNSCC). Methods and Materials: Archived biopsy material was obtained for 78 patients with squamous cell carcinoma of the oropharynx who received primary radiotherapy with curative intent. Immunohistochemistry was used to detect MVP expression. Locoregional failure and cancer-specific survival were estimated using cumulative incidence and Cox multivariate analyses. Results: In a univariate and multivariate analysis, MVP expression was strongly associated with both locoregional failure and cancer-specific survival. After adjustment for disease site, stage, grade, anemia, smoking, alcohol, gender, and age, the estimated hazard ratio for high MVP (2/3) compared with low (0/1) was 4.98 (95% confidence interval, 2.17‐11.42; p 0.0002) for locoregional failure and 4.28 (95% confidence interval, 1.85‐9.95; p 0.001) for cancer-specific mortality. Conclusion: These data are the first to show that MVP may be a useful prognostic marker associated with radiotherapy resistance in a subgroup of patients with HNSCC. © 2007 Elsevier Inc.

Pupose: Fragile histidine triad (FHIT) expression in precursor oral lesions (POL) and oral squamous cell carcinomas (OSCC) was studied with regard to (a) the frequency of loss of FHIT expression, (b) whether loss of FHIT expression correlates with degree of dysplasia in POLs, (c) whether FHIT loss predicts high-risk POLs that are more likely to transform, and (d) whether FHIT loss in OSCCs correlates with survival. Experimental Design: Ninety-four POLs and 86 OSCCs were immunostained for FHIT. Survival analysis was done for cases with validated clinical outcomes. Results: By optimizing the immunostaining protocol, we found that FHIT is expressed in a distinctive strong nuclear and weak cytoplasmic pattern in oral tissues. Loss of FHIT expression was found in 42 of 94 (45%) POLs and in 66 of 86 (77%) OSCCs. We observed a statistically significant positive correlation between frequency of FHIT loss and increasing grade of dysplasia (χ2 = 13.8; degrees of freedom = 4; P = 0.008). Loss of FHIT expression in POLs that progressed to malignancy was more frequent than in those that did not [17 of 25 (68%) versus 12 of 29 (41.4%), respectively]. This difference was statistically significant (χ2 = 3.8; degrees of freedom = 1; P = 0.046). In OSCCs, loss of FHIT staining indicated a worse prognosis (survival rate, 36.2%) than when positive FHIT staining was observed (survival rate, 50%), but the difference was not statistically significant (P = 0.546, Kaplan-Meier, log-rank). Conclusions: FHIT seems to localize to both nuclear and cytoplasmic domains. FHIT inactivation occurs early in oral carcinogenesis and may be useful molecular marker for progressive dysplastic oral lesions.

The co-occurrence of two rare recessive genetic conditions in apparently unrelated individuals or families is extremely rare. Two geographically distant and apparently unrelated families were identified in which individuals were simultaneously affected by two rare recessive mendelian syndromes, Papillon-Lefevre syndrome and type 1 oculocutaneous albinism. The families were tested for mutations in the causative genes, cathepsin C (CTSC) and tyrosinase (TYR), respectively, by direct sequencing. To assess the relationship of the two families, both families were tested for polymorphisms at eight microsatellite markers spanning both CTSC and TYR loci. Independent mutations (c.318-1G-->A and c.817G-->C/p.W272C) were identified in CTSC and TYR, respectively, that were shared by the affected individuals in both families. The two affected genes lie close together on chromosome bands 11q14.2-14.3, and studies with linked genetic markers suggested that the families shared a small chromosomal segment carrying both mutations that had been transmitted intact from a remote common ancestor. The co-occurrence of the two rare diseases in multiple families depends on their shared chromosomal location, but not on any shared pathogenic mechanism.

Lenz microphthalmia is inherited in an X-linked recessive pattern and comprises microphthalmia, mental retardation, and skeletal and other anomalies. Two loci associated with this syndrome, MAA (microphthalmia with associated anomalies) and MAA2, are situated respectively at Xq27-q28 (refs. 1,2) and Xp11.4-p21.2 (ref. 3). We identified a substitution, nt 254C-->T; P85L, in BCOR (encoding BCL-6-interacting corepressor, BCOR) in affected males from the family with Lenz syndrome previously used to identify the MAA2 locus. Oculofaciocardiodental syndrome (OFCD; OMIM 300166) is inherited in an X-linked dominant pattern with presumed male lethality and comprises microphthalmia, congenital cataracts, radiculomegaly, and cardiac and digital abnormalities. Given their phenotypic overlap, we proposed that OFCD and MAA2-associated Lenz microphthalmia were allelic, and we found different frameshift, deletion and nonsense mutations in BCOR in seven families affected with OFCD. Like wild-type BCOR, BCOR P85L and an OFCD-mutant form of BCOR can interact with BCL-6 and efficiently repress transcription. This indicates that these syndromes are likely to result from defects in alternative functions of BCOR, such as interactions with transcriptional partners other than BCL-6. We cloned the zebrafish (Danio rerio) ortholog of BCOR and found that knock-down of this ortholog caused developmental perturbations of the eye, skeleton and central nervous system consistent with the human syndromes, confirming that BCOR is a key transcriptional regulator during early embryogenesis.

We have previously reported that loss-of-function mutations in the cathepsin C gene (CTSC) result in Papillon-Lefèvre syndrome, an autosomal recessive condition characterized by palmoplantar keratosis and early-onset, severe periodontitis. Others have also reported CTSC mutations in patients with severe prepubertal periodontitis, but without any skin manifestations. The possible role of CTSC variants in more common types of non-mendelian, early-onset, severe periodontitis ("aggressive periodontitis") has not been investigated. In this study, we have investigated the role of CTSC in all three conditions. We demonstrate that PLS is genetically homogeneous and the mutation spectrum that includes three novel mutations (c.386TA/p.V129E, c.935AG/p.Q312R, and c.1235AG/p.Y412C) in 21 PLS families (including eight from our previous study) provides an insight into structure-function relationships of CTSC. Our data also suggest that a complete loss-of-function appears to be necessary for the manifestation of the phenotype, making it unlikely that weak CTSC mutations are a cause of aggressive periodontitis. This was confirmed by analyses of the CTSC activity in 30 subjects with aggressive periodontitis and age-sex matched controls, which demonstrated that there was no significant difference between these two groups (1,728.7 +/- SD 576.8 micro moles/mg/min vs. 1,678.7 +/- SD 527.2 micro moles/mg/min, respectively, p = 0.73). CTSC mutations were detected in only one of two families with prepubertal periodontitis; these did not form a separate functional class with respect to those observed in classical PLS. The affected individuals in the other prepubertal periodontitis family not only lacked CTSC mutations, but in addition did not share the haplotypes at the CTSC locus. These data suggest that prepubertal periodontitis is a genetically heterogeneous disease that, in some families, just represents a partially penetrant PLS.

Background PLS is a rare autosomal recessive disorder characterized by early onset periodontopathia and palmar plantar keratosis. PLS is caused by mutations in the cathepsin C (CTSC) gene. Dipeptidyl-peptidase I encoded by the CTSC gene removes dipeptides from the amino-terminus of protein substrates and mainly plays an immune and inflammatory role. Several mutations have been reported in this gene in patients from several ethnic groups. We report here mutation analysis of the CTSC gene in three Indian families with PLS. Methods Peripheral blood samples were obtained from individuals belonging to three Indian families with PLS for genomic DNA isolation. Exon-specific intronic primers were used to amplify DNA samples from individuals. PCR products were subsequently sequenced to detect mutations. PCR-SCCP and ASOH analyses were used to determine if mutations were present in normal control individuals. Results All patients from three families had a classic PLS phenotype, which included palmoplantar keratosis and early-onset severe periodontitis. Sequence analysis of the CTSC gene showed three novel nonsense mutations (viz., p.Q49X, p.Q69X and p.Y304X) in homozygous state in affected individuals from these Indian families. Conclusions This study reported three novel nonsense mutations in three Indian families. These novel nonsense mutations are predicted to produce truncated dipeptidyl-peptidase I causing PLS phenotype in these families. A review of the literature along with three novel mutations reported here showed that the total number of mutations in the CTSC gene described to date is 41 with 17 mutations being located in exon 7.

We and others previously identified a region of hemizygous or homozygous deletion at chromosome band 8p23 in oral and oropharyngeal squamous cell carcinomas (OSCCs) and many other cancer types, suggesting the presence of a tumor-suppressor gene (TSG) in this region. Recently, based on a single region of homozygous deletion in head and neck squamous cell carcinomas (HNSCC), a putative TSG, CUB and sushi multiple domains-1 (CSMD1), has been identified. In the present study, we mapped three OSCC cell lines with previously described homozygous deletions at a high resolution onto a detailed physical map. Critically, this map covered a wider region than that used in previous studies, and in contrast to these studies, our results revealed multiple regions of homozygous deletion within a small interval on 8p23. To investigate this deletion pattern further, we generated a panel of 34 sequence tagged site (STS) markers spanning the region and tested these three cell lines and an additional 34 OSCC cell lines, identifying homozygous deletions in a further four. Combining the results from all seven deleted cell lines identified three non-overlapping regions of homozygous deletion. This complex pattern could be consistent with the presence of multiple TSGs or one very large TSG in this region, and/or specific chromosomal instability. CSMD1 spans two of the three deleted regions and, therefore, would appear to be an excellent candidate for a TSG. However, deletion mapping with STSs corresponding to the exons of CSMD1 shows that some of the deletions do not interrupt its coding region, and in other cell lines the coding region is interrupted by two discontinuous homozygous deletions, suggesting the presence of redundant deletions. These results call into question whether the CSMD1 gene is the 8p23 TSG or whether this or any other genes at this locus are involved in the development of OSCC.

Familial melanoma predisposition is associated with germline mutations at the CDKN2A/ARF locus in up to 40% of families. The exact role of the two proteins encoded by this complex locus in this predisposition is unclear. Most mutations affect either CDKN2A only or products of both genes. Recently a deletion affecting ARF-specific exon 1beta was reported in a family with melanoma and neural tumours. However, the possibility of this deletion also altering the CDKN2A transcript could not be excluded. More convincingly, a 16 base pair insertion in exon 1beta has been reported in an individual with multiple melanomas suggesting a direct role for ARF in melanoma predisposition. We report here a splice mutation in exon 1beta in a family with melanoma that results in ARF haploinsufficiency. The mutation was observed in a mother and daughter with melanoma. A sibling of the mother with breast cancer also had this mutation. Analysis of the melanoma from one individual revealed a 62 bp deletion in exon 3 of the wildtype allele and loss of the mutant allele; these somatic changes would affect both CDKN2A and ARF. These somatic events suggest that concomitant inactivation of both ARF and CDKN2A may be necessary for melanoma development and that mutations in ARF and CDKN2A possibly confer different levels of susceptibility to melanoma, with the former associated with lesser predisposition. In this situation, the events follow a 'three-hit' model as observed in tumours from FAP patients with an attenuated phenotype. Overall, the data suggest a direct role for ARF haploinsufficiency in melanoma predisposition and co-operation between ARF and CDKN2A in tumour formation, consistent with recent observations in Cdkn2a-specific knockout mice.

This study appeared in full in the last issue of Research Ethics Review (2010; 6 (2): 67). Dr Arber, a cancer biologist in Chesterpool oncology services and working at Chesterpool University wishes to study prevalence and nature of somatic mutations in selected genes associated with breast cancer. She proposes to use, without specific consent, tumour and normal tissues from 100 positive breast biopsies already collected in the clinical service and analyse selected genes that are suspected to be altered in breast cancer. A year later she submits an amendment to allow whole genome sequencing of the tumour DNA and for comparison, blood DNA.

Papillon-Lefèvre syndrome, or keratosis palmoplantaris with periodontopathia (PLS, MIM 245000), is an autosomal recessive disorder that is mainly ascertained by dentists because of the severe periodontitis that afflicts patients. Both the deciduous and permanent dentitions are affected, resulting in premature tooth loss. Palmoplantar keratosis, varying from mild psoriasiform scaly skin to overt hyperkeratosis, typically develops within the first three years of life. Keratosis also affects other sites such as elbows and knees. Most PLS patients display both periodontitis and hyperkeratosis. Some patients have only palmoplantar keratosis or periodontitis, and in rare individuals the periodontitis is mild and of late onset. The PLS locus has been mapped to chromosome 11q14-q21 (refs 7, 8, 9). Using homozygosity mapping in eight small consanguineous families, we have narrowed the candidate region to a 1.2-cM interval between D11S4082 and D11S931. The gene (CTSC) encoding the lysosomal protease cathepsin C (or dipeptidyl aminopeptidase I) lies within this interval. We defined the genomic structure of CTSC and found mutations in all eight families. In two of these families we used a functional assay to demonstrate an almost total loss of cathepsin C activity in PLS patients and reduced activity in obligate carriers.

Bizarre parosteal osteochondromatous proliferations are a rare subgroup of the osteochondromatous lesions. They must be differentiated from reactive osteochondromatous proliferations, low grade parosteal osteogenic sarcoma, and chondrosarcoma. Their recognition is important from the point of view of management, which should be by simple excision. This article describes a case of bizarre parosteal osteochondromatous proliferation in a 2-year-old child; the lesion developed in the anterior maxilla, a previously unreported site.

Early identification and prophylactic surgery are essential in preventing development of malignancy in colorectal polyps in familial adenomatous polyposis (FAP). Previous studies indicate a 100% cumulative risk of developing colonic polyps in individuals with FAP by the age of 34 yr. However, we have previously reported late-onset and non-penetrance of polyposis in four families. We describe here in detail one of these families with florid oral manifestations detectable on panoramic radiography of the jaws, which were instrumental in the diagnosis of FAP in the index patient and for ascertainment of her family for screening. The pathological adenomatous polyposis coli (APC) gene mutation in this family was shown to segregate with dento-osseous changes. Panoramic jaw radiography is a common examination carried out prior to dental or oral surgical procedures. This case illustrates the importance of appropriate investigations, including family history and colonoscopy, even in relatively older patients with radiological findings such as those described here and in members of their families at risk of FAP.

A weighted scoring system (Dental Panoramic Radiograph Score) taking into consideration the nature, extent, and site of osseous and dental changes on dental panoramic radiographs in familial adenomatous polyposis is described. The weighting takes into consideration the incidence of the anomaly in the general population. The reliability of the system was tested by application to 85 people known to be affected by clinical or mutation analysis, 30 people lacking mutation in the adenomatous polyposis gene, and 19 people shown to be at low risk (< 1%) by linkage analysis. Using the highest thresholds, a specificity of 100% and sensitivity of approximately 68% was obtained. If all positive findings were considered as significant, sensitivity was increased to approximately 82% but the specificity was reduced to approximately 88%. Significant DPRS findings were observed at a significantly higher frequency in patients aged over 20 compared to the patients aged 20 and under. Overall, approximately 68% of the affected subjects had significant changes, and approximately 18% had normal appearance on DPR, with the remainder having changes classified as minimal or equivocal.