Markus Martini

Long-term results of endosteal implants following radical oral cancer surgery with and without adjuvant radiation therapy.

PURPOSE The aim of this study was to analyze the long-term survival of implants and implant-retained prostheses in patients after ablative surgery of oral cancer with or without adjunctive radiation therapy. MATERIALS AND METHODS Between 1997 and 2008, 66 patients who had undergone ablative tumor surgery in the oral cavity were treated with dental implants (n = 262). Thirty-four patients received radiation therapy in daily fractions of 2 Gy administered on 18 to 30 days. Implants were inserted in the maxilla (49; 18.7%) or mandible (213; 81.3%), in non-irradiated residual (65; 24.8%) or grafted bone (44; 16.8%) and in irradiated residual (15.6%) or grafted bone (39; 14.9%). Seventeen fixed protheses and 53 removable dentures (34 bar attachments, 9 telescopic and 10 ball retained dentures) were inserted. RESULTS Mean follow-up after implant insertion was 47.99 (±34.31) months (range 12-140 months). The overall 1-, 5-, and 10-year survival rates of all implants were 96.6%, 96.6%, and 86.9%, respectively. Fourteen implants were lost in nine patients (5.3% of all implants); eight implants were primary losses, and five secondary losses because of an operation of tumor recurrence. There was no significantly lower implant survival for implants inserted into irradiated bone (p = .302), bone and/or soft-tissue grafts (p = .436), and maxilla or mandible (p = .563). All prosthetic restorations in patients without tumor recurrence could be maintained during the observation period. CONCLUSIONS Implant survival is not significantly influenced by radiation therapy, grafts (bone and/or soft tissue), or location (maxilla or mandible). However, implants placed in irradiated bone exhibit a higher failure rate during the healing period than those placed in non-irradiated bone. No superstructure was particularly favorable. Osseointegrated implants can be used successfully in patients with prior history of ablative surgery with and without additional radiation therapy.

IRF6 gene variants in Central European patients with non-syndromic cleft lip with or without cleft palate

Variants in the interferon regulatory factor 6 (IRF6) gene have repeatedly been associated with non-syndromic cleft lip with or without cleft palate (NSCL/P). A recent study has suggested that the functionally relevant variant rs642961 is the underlying cause of the observed associations. We genotyped rs642961 in our Central European case-control sample of 460 NSCL/P patients and 952 controls. In order to investigate whether other IRF6 variants contribute independently to the etiology of NSCL/P, we also genotyped the non-synonymous coding variant V274I (rs2235371) and five IRF6-haplotype tagging single nucleotide polymorphisms (SNPs). A highly significant result was observed for rs642961 (P = 1.44 x 10(-6)) in our sample. The odds ratio was 1.75 [95% confidence interval (CI): 1.38-2.22] for the heterozygous genotype and 1.94 (95% CI: 1.21-3.10) for the homozygous genotype, values that are similar to those reported in a previously published family-based study. Our results thus confirm the involvement of the IRF6 variant, rs642961, in the etiology of NSCL/P in the Central European population. We also found evidence suggestive of an independent protective effect of the coding variant V274I. In order to understand fully the genetic architecture of the IRF6 locus, it will be necessary to conduct additional SNP-based and resequencing studies using large samples of patients.

Strong Association of Variants around FOXE1 and Orofacial Clefting

Nonsyndromic orofacial clefting (nsOFC) is a common, complex congenital disorder. The most frequent forms are nonsyndromic cleft lip with or without cleft palate (nsCL/P) and nonsyndromic cleft palate only (nsCPO). Although they are generally considered distinct entities, a recent study has implicated a region around the FOXE1 gene in both nsCL/P and nsCPO. To investigate this hypothesis, we analyzed the 2 most strongly associated markers (rs3758249 and rs4460498) in 2 independent samples of differing ethnicities: Central European (949 nsCL/P cases, 155 nsCPO cases, 1163 controls) and Mayan Mesoamerican (156 nsCL/P cases, 10 nsCPO cases, 338 controls). While highly significant associations for both single-nucleotide polymorphisms were obtained in nsCL/P (rs4460498: pEurope = 6.50 × 10−06, pMayan = .0151; rs3758249: pEurope = 2.41 × 10−05, pMayan = .0299), no association was found in nsCPO (p > .05). Genotyping of rs4460498 in 472 independent European trios revealed significant associations for nsCL/P (p = .016) and nsCPO (p = .043). A meta-analysis of all data revealed a genomewide significant result for nsCL/P (p = 1.31 × 10−08), which became more significant when nsCPO cases were added (pnsOFC = 1.56 × 10−09). These results strongly support the FOXE1 locus as a risk factor for nsOFC. With the data of the initial study, there is now considerable evidence that this locus is the first conclusive risk factor shared between nsCL/P and nsCPO.

Human Beta-Defensin-1, -2, and -3 Exhibit Opposite Effects on Oral Squamous Cell Carcinoma Cell Proliferation

The objective of this study was to investigate the impact of human beta-defensins (hBDs) on oral squamous cell carcinoma (OSCC) proliferation and hBD expression in vitro. BHY-OSCC cell lines were stimulated with hBD-1, -2, and -3. Proliferation of BHY cells was ascertained and hBD-mRNA expression was evaluated by real-time PCR. Proliferation of BHY cells decreased by 25% in response to hBD-1 stimulation but increased after stimulation with hBD-2 and -3. HBD-1 stimulation enhanced hBD-3 expression, whereas HBD-2 stimulation decreased early hBD-3 expression. HBD-3 stimulation enhanced hBD-1 expression. HBDs profoundly impact on OSCC proliferation and hBD expression in vitro. Therefore, hBD-1 might function as a tumor suppressor gene in OSCCs, while hBD-2 and -3 might be protooncogenes.

Genome-wide linkage scan of nonsyndromic orofacial clefting in 91 families of central European origin†

Orofacial clefts are among the most common of all congenital disorders. Nonsyndromic cases of cleft lip with or without cleft palate (NSCL/P) and cleft palate only (NSCPO) are considered to have a multifactorial etiology which involves both genetic and environmental factors. We present the results of a genome‐wide linkage scan in 91 families of central European descent with nonsyndromic orofacial clefts (NSC). The sample included 74 NSCL/P families, 15 NSCPO families, and 2 mixed families (a total of 217 affected and 230 unaffected individuals were genotyped). We genotyped 542 microsatellite markers (average intermarker distance = 6.9 cM). Multipoint nonparametric linkage analysis was performed using Allegro 2.0f. In addition to the factors investigated in previous genome‐wide linkage analyses, we searched for sex‐specific susceptibility loci, loci demonstrating parental imprinting and loci that are shared by NSCL/P and NSCPO. Several genomic regions likely to contain susceptibility loci for NSC were identified at the level of nominal significance. Some of these overlap with regions identified in previous studies. Suggestive evidence of linkage was obtained for the loci 4q21‐q26 and 1p31‐p21, with the chromosome 1 locus showing a male‐specific genetic effect. Our study has identified promising chromosomal regions for the identification of NSC‐associated genes, and demonstrates the importance of performing detailed statistical analyses which take into account complex genetic mechanisms such as sex‐specific effects and genomic imprinting. Further research in large patient samples is necessary to identify factors common to NSCL/P and NSCPO.

Decreased gene expression of human β-defensin-1 in the development of squamous cell carcinoma of the oral cavity

The aim of this study was to investigate the gene expression of human beta-defensin-1, -2, -3 (hBD-1, -2, -3), interleukin-1beta, tumour necrosis factor-alpha and cyclooxygenase-2 in oral squamous cell carcinoma (OSCC) compared to benign and premalignant lesions as well as healthy controls. Biopsies of healthy gingiva (n=5), irritation fibroma (n=5), leukoplakia (n=5) and OSCC (n=5) were obtained during routine surgical procedures. RNA was extracted according to standard protocols and transcripts of hBD-1, -2, -3, interleukin-1beta, tumour necrosis factor-alpha and cyclooxygenase-2 were analysed by real-time polymerase chain reaction. The expression of hBD-1 was reduced in all lesions (5-fold in irritation fibroma and 2.5-fold in leukoplakia), but most significantly (50-fold) in OSCC. hBD-1 appears to play a role in the development of OSCC. The loss of its function might contribute to the malignant progression of these tumours.

TGFB3 displays parent-of-origin effects among central Europeans with nonsyndromic cleft lip and palate

AbstractMice with a deletion of Tgf-β3 (−/−) and association studies in humans of different ethnicities support the involvement of TGFB3 in the etiology of orofacial clefts. In this study, we investigated the relevance of TGFB3 in the development of cleft lip and palate (CL/P) among 204 triads of central European origin. Transmission-disequilibrium test (TDT) analysis revealed no significant transmission distortions for each marker alone, and none for any possible haplotypes. However, we found strong evidence for parent-of-origin effects, with lower risk of maternal transmission compared with paternal transmission [IM = 0.38; confidence interval (CI): 0.17–0.86] of the risk allele T to an affected offspring at marker rs2300607. This is also expressed in an increased risk of heterozygous children having the T allele inherited from the father (RP = 3.47; CI: 1.32–9.11). Our data support the involvement of TGFB3 in the development of oral clefts in patients of central European origin.

Nuclear hBD-1 accumulation in malignant salivary gland tumours

BackgroundWhereas the antimicrobial peptides hBD-2 and -3 are related to inflammation, the constitutively expressed hBD-1 might function as 8p tumour suppressor gene and thus play a key role in control of transcription and induction of apoptosis in malignant epithelial tumours. Therefore this study was conducted to characterise proteins involved in cell cycle control and host defence in different benign and malignant salivary gland tumours in comparison with healthy salivary gland tissue.Methods21 paraffin-embedded tissue samples of benign (n = 7), and malignant (n = 7) salivary gland tumours as well as healthy (n = 7) salivary glands were examined immunohistochemically for the expression of p53, bcl-2, and hBD-1, -2, -3.ResultsHBD-1 was distributed in the cytoplasm of healthy salivary glands and benign salivary gland tumours but seems to migrate into the nucleus of malignant salivary gland tumours. Pleomorphic adenomas showed cytoplasmic as well as weak nuclear hBD-1 staining.ConclusionHBD-1, 2 and 3 are traceable in healthy salivary gland tissue as well as in benign and malignant salivary gland tumours. As hBD-1 is shifted from the cytoplasm to the nucleus in malignant salivary gland tumours, we hypothesize that it might play a role in the oncogenesis of these tumours. In pleomorphic adenomas hBD-1 might be connected to their biologic behaviour of recurrence and malignant transformation.

Gene expression of oncogenes, antimicrobial peptides, and cytokines in the development of oral leukoplakia.

OBJECTIVE The aim of this study was to investigate the expression pattern of oncogenes, antimicrobial peptides, and genes involved in inflammation in leukoplakia of the oral cavity compared with healthy gingiva. STUDY DESIGN Biopsies of healthy gingiva (n=20) and leukoplakia (n=20), were obtained during routine surgical procedures. RNA was extracted according to standard protocols. Transcript levels of alpha-defensin (DEFA) 1/3, DEFA-4, S100-A7, deleted-in-oral-cancer (Doc) 1, interleukin (IL) 1beta, IL-6, IL-8, IL-10, tumor necrosis factor (TNF) alpha, cyclooxygenase (Cox) 2, epidermal growth factor (EGF), keratinocyte growth factor (KGF), transforming growth factor (TGF) beta1, TGF-alpha, collagen-IA1 (Col-1), and tenascin-c were analyzed by real-time reverse-transcription polymerase chain reaction. The proteins encoded by the different genes were visualized by immunostaining. RESULTS Compared with healthy gingiva (set as 1), there was an increased gene expression of DEFA-4 (179.2-fold), S100-A7 (25.4-fold), EGF (24.8-fold), TGF-beta1 (25.2-fold), and tenascin-c (34.3-fold) in oral leukoplakia. The expression of IL-1beta and Doc-1 was decreased (0.01-fold and 0.2-fold, respectively). CONCLUSIONS The combination of an increased expression of the antimicrobial peptide DEFA-4, the oncogene S100-A7, EGF, and tenascin-c, and a decreased Doc-1 expression in oral leukoplakia might characterize its potency of malignant transformation. Chronic inflammation seems not to be involved in the development of this lesion.

Mutation Screening in the IRF6-Gene in Patients With Apparently Nonsyndromic Orofacial Clefts and a Positive Family History Suggestive of Autosomal-Dominant Inheritance

Stefanie Birnbaum,* Heiko Reutter, Carola Lauster, Martin Scheer, Gül Schmidt, Mitra Saffar, Markus Martini, Alexander Hemprich, Henning Henschke, Franz-Josef Kramer, and Elisabeth Mangold Institute of Human Genetics, University of Bonn, Bonn, Germany Department of Cleft Lip and Cleft Palate Surgery, Humboldt University of Berlin, Berlin, Germany Department of Oral and Maxillo-Facial Surgery, University of Cologne, Köln, Germany Department of Orthodontics, University of Cologne, Köln, Germany Department of Oral and Maxillo-Facial Surgery, University of Bonn, Bonn, Germany Department of Oral and Maxillo-Facial Surgery, University of Leipzig, Leipzig, Germany Institute for Medical Biometry, Informatics and Epidemiology, University of Bonn, Bonn, Germany Department of Oral and Maxillo-Facial Surgery, University of Göttingen, Göttingen, Germany