Combination chemotherapy for head and neck cancer: the addition of Bcl-2 inhibitors

Locoregionally advanced, recurrent and/or metastatic head and neck squamous cell carcinoma (HNSCC) lacks a validated therapeutic approach. Evidence emphasizes the importance of Bcl-2, Bcl-XL and survivin as survival factors in HNSCC cells. Targeting the Bcl-2 system is therefore an attractive strategy for restoring a 'normal' apoptotic process in HNSCC, making cells more susceptible to conventional chemotherapy and disrupting neovascularization. Among Bcl-2 inhibitors, non-peptidic small molecules hold substantial promise in HNSCC adjuvant therapy. Predicting treatment response requires the precise profiling of tumors, ideally by the use of panels that include markers from different pathways; the further definition of such panels may benefit from proteomic and/or pharmacogenomic approaches. Furthermore, in combination treatments, the effect of drug delivery sequence requires further investigation.

Expression of beta-catenin in human tooth germ

OBJECTIVE

To evaluate beta-catenin expression in human tooth germ development.

STUDY DESIGN

Specimens of 7 human fetuses aged between the ninth and sixteenth week were examined for beta-catenin expression by immunohistochemistry.

RESULTS

In the bud stage, we observed catenin membranous positivity for all primitive dental lamina and dental ridge cells, cytoplasmic positivity for tooth bud and intense nuclear positivity for early-condensed dental mesenchyme. The cap stage was marked by intense cytoplasmic and nuclear positivity in the outer and inner enamel epithelium and the dental papilla and by moderate cytoplasmic positivity in the enamel knot. In the early bell stage, we noted strong cytoplasmic and nuclear staining in the inner and outer enamel epithelium, only moderate membranous and cytoplasmic staining in the stellate reticulum, a high percentage of intense nuclear positivity in the dental papilla and strong focal nuclear and cytoplasmic positivity in the dental sac.

CONCLUSION

All areas with close contact between epithelial structures and ectomesenchymal cells showed increased expression of delocalized cytoplasmic and nuclear beta-catenin. Nuclear localization, tissue expression pattern and timing suggest a pivotal role for beta-catenin in the transcriptional activation of genes probably involved in the mesenchyme-epithelial interactions on which human tooth development is based.

Antibiotic prophylaxis in dentistry and oral surgery: use and misuse

INTRODUCTION

Antibiotic prophylaxis (AP) still represents a common but often misused procedure in dental practice, thus aggravating the risk for antimicrobial resistance and adverse effects occurrence.

AIMS AND METHODS

Our primary objective is to review the available scientific evidence regarding AP in dentistry both among healthy subjects and medically compromised patients. Additionally, the latest available guidelines provided by some of the most authoritative associations are here discussed.

RESULTS AND CONCLUSIONS

AP is advisable only in a small percentage of patients where a risk of severe infective complications (i.e. infective endocarditis and prosthetic joint infection, septicaemia in severely immuno-compromised patients, bisphosphonate-related osteonecrosis of the jaw) exists. On the contrary, little or no scientific evidence exists for AP in subjects with other systemic diseases as well as in healthy individuals. This pioneering recommendation is strongly evidence-based, since a consistent association between any dental procedure and the development of local and distant infective complications is still lacking. In addition, the daily bacteraemia secondary to routine habits has been thought to be robustly associated with a greater risk of systemic disease bacterial-related than a single dental procedure exposure. Compliance of general dental or family practitioners to the current recommendations seems not to be optimal, thus, efforts to improve it should be planned and undertaken.

Expression of E-cadherin, beta-catenin and APC protein in canine colorectal tumours

The present study aimed at evaluating, through immunohistochemical staining, E-cadherin, beta-catenin and adenomatous polyposis coli (APC) expression and distribution in normal, dysplastic and neoplastic canine colon and rectum, and at correlating the protein expression with the histological grade of malignancy. In order to obtain a more thorough evaluation of the APC/beta catenin complex, both proteins were also assessed for colocalization in neoplastic cells through double immunofluorescence staining. Immunohistochemical investigation showed a marked decrease of E-cadherin and APC expression in malignant tumours, while a lack of membranous beta-catenin distribution and a cytoplasmic positivity, rather than a decrease of expression, was observed in less differentiated carcinomas. Confocal laser microscopical observation showed cytoplasmic beta-catenin distribution solely in APC-negative cells, demonstrating that the correct beta-catenin distribution on the cell membrane can be APC dependent, as in human colorectal carcinomas. Therefore, the changes in adhesion molecules can play a very important role both in colorectal carcinogenesis and in malignant progression; moreover, these proteins can also be considered powerful prognostic tools in veterinary oncology.

Effect of p63 Expression on Survival in Oral Squamous Cell Carcinoma

BACKGROUND

P63 is the protein codified by p63 gene, a p53 gene homolog, known for its pivotal role in cell cycle regulation, and involved in the tumor differentiation. Aims of the present study were to assess the frequency and pattern of p63 protein expression in oral squamous cell carcinoma (OSCC) in relation to the main tumour characteristics and to verify whether p63 can be considered a marker of prognosis in patients with OSCC.

MATERIAL AND METHODS

In a retrospective study, a cohort of 64 OSCC patients was investigated for p63 protein expression and its cellular localization by immunohistochemistry (monoclonal mouse anti-human p63 protein-clone 4A4). After grouping by p63 expression, OSCCs were statistically analyzed for the variables age, gender, histological grading (G), TNM, staging, recurrence, and overall survival rate.

RESULTS

The overall frequency of p63 overexpressed was of 57.8 percent. Various p63 staining patterns were observed according to G score, with a significant correlation between p63 overexpression and the lowest G score (P < 0.0001). No statistically significant difference was found between p63 pattern expression and age, sex, staging. OSCC patients with p63 overexpressed were found to have a poorer survival rate with respect to OSCCs with a normal pattern of expression (P = 0.024).

CONCLUSIONS

On the basis of these results, it is possible to suggest p63 pattern expression as a reliable indicator of histological grading and an early marker of poor prognosis.

Immediate Placement and Temporization of Implants: Three- to Five-year Retrospective Results

The immediate placement of dental implants in esthetic areas is a primary challenge for modern implantology. The underlying treatment goal is to preserve the natural periodontal architecture; in recent years, however, a concurrent goal has been to reduce the period between implant placement in the fresh extraction socket and delivery of the definitive restoration, but adequate long-term data are still lacking on the efficacy of this technique. A 3- to 5-year retrospective analysis of 282 dental implants immediately placed into extraction sockets, and temporized with nonoccluding provisional prostheses has been undertaken. All recorded outcomes and complications, as well as a proposed protocol for management of immediate function, are discussed.

Survivin expression in renal cell carcinoma

Deregulated expression of inhibitors of apoptosis may contribute to cancer by aberrantly extending cell viability and facilitating the insurgence of resistance to chemo- and radiotherapy. In this study, we have investigated, by immunohistochemical technique, the expression and potential prognostic significance of survivin in a series of 49 clear cell type renal cell carcinoma (ccRCC). Survivin expression was significantly associated with poorly differentiated, advanced stages and more aggressive ccRCCs (p < 0.05). Patients with low survivin expression had statistically significant better survival rates than patients with high survivin expression (p < 0.05). This may be relevant for follow-up protocols design and/or alternative therapeutic approaches.

Nevoid basal cell carcinoma syndrome (Gorlin syndrome)

Nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome, is a hereditary condition characterized by a wide range of developmental abnormalities and a predisposition to neoplasms.

The estimated prevalence varies from 1/57,000 to 1/256,000, with a male-to-female ratio of 1:1.

Main clinical manifestations include multiple basal cell carcinomas (BCCs), odontogenic keratocysts of the jaws, hyperkeratosis of palms and soles, skeletal abnormalities, intracranial ectopic calcifications, and facial dysmorphism (macrocephaly, cleft lip/palate and severe eye anomalies). Intellectual deficit is present in up to 5% of cases. BCCs (varying clinically from flesh-colored papules to ulcerating plaques and in diameter from 1 to 10 mm) are most commonly located on the face, back and chest. The number of BBCs varies from a few to several thousand. Recurrent jaw cysts occur in 90% of patients. Skeletal abnormalities (affecting the shape of the ribs, vertebral column bones, and the skull) are frequent. Ocular, genitourinary and cardiovascular disorders may occur. About 5–10% of NBCCS patients develop the brain malignancy medulloblastoma, which may be a potential cause of early death.

NBCCS is caused by mutations in the PTCH1 gene and is transmitted as an autosomal dominant trait with complete penetrance and variable expressivity.

Clinical diagnosis relies on specific criteria. Gene mutation analysis confirms the diagnosis. Genetic counseling is mandatory. Antenatal diagnosis is feasible by means of ultrasound scans and analysis of DNA extracted from fetal cells (obtained by amniocentesis or chorionic villus sampling). Main differential diagnoses include Bazex syndrome, trichoepithelioma papulosum multiplex and Torre's syndrome (Muir-Torre's syndrome).

Management requires a multidisciplinary approach. Keratocysts are treated by surgical removal. Surgery for BBCs is indicated when the number of lesions is limited; other treatments include laser ablation, photodynamic therapy and topical chemotherapy. Radiotherapy should be avoided. Vitamin A analogs may play a preventive role against development of new BCCs.

Life expectancy in NBCCS is not significantly altered but morbidity from complications can be substantial. Regular follow-up by a multi-specialist team (dermatologist, neurologist and odontologist) should be offered. Patients with NBCCS should strictly avoid an excessive sun exposure.

Titanium acts on osteoblast translational process

Titanium is a highly biocompatible material and very osteogenic in vivo. However, how titanium regulates osteoblast activity to promote bone formation is incompletely characterized. We, therefore, attempted to get more information by using microRNA (miRNA) microarray techniques to investigate translation regulation in osteoblasts grown on titanium disks. The miRNA oligonucleotide microarray provides a novel method to carry out genome-wide miRNA profiling in human samples. By using miRNA microarrays containing 329 probes designed from the human miRNA sequence, several miRNA were identified in osteoblast-like cell line (MG 63) grown on titanium disks. There were 13 upregulated miRNAs (ie, mir-23a, mir-222, mir-523, mir-22, mir-23b, mir-143, mir-377, mir-24, mir-422b, mir-26a, mir-29a, mir-17-5p, mir-182) and 2 down-regulated miRNAs (ie, mir-187, mir-339). The data reported are, to our knowledge, the first study on translation regulation in osteoblasts exposed to titanium. The data can be relevant to understand better the molecular mechanism of osteoblast activation and as a model for comparing other materials with similar clinical effects.

Prognostic value analysis of urokinase-type plasminogen activator receptor in oral squamous cell carcinoma: an immunohistochemical study

Background

Oral squamous cell carcinoma (OSCC) represents the most common oral malignancy. Despite recent advances in therapy, up to 50% of the cases have relapse and/or metastasis. There is therefore a strong need for the identification of new biological markers able to predict the clinical behaviour of these lesions in order to improve quality of life and overall survival. Among tumour progression biomarkers, already known for their involvement in other neoplasia, a crucial role is ascribed to the urokinase-type plasminogen activator receptor (uPAR), which plays a multiple role in extracellular proteolysis, cell migration and tissue remodelling not only as a receptor for the zymogen pro-uPA but also as a component for cell adhesion and as a chemoattractant. The purpose of this study was to gain information on the expression of uPAR in OSCC and to verify whether this molecule can have a role as a prognostic/predictive marker for this neoplasia.

Methods

In a retrospective study, a cohort of 189 OSCC patients was investigated for uPAR expression and its cellular localization by immunohistochemistry. As standard controls, 8 normal oral mucosal tissues free of malignancy, obtained from patients with no evidence or history of oral cavity tumours, were similarly investigated. After grouping for uPAR expression, OSCCs were statistically analyzed for the variables age, gender, histological grading (G), tumour size, recurrence, TNM staging and overall survival rate.

Results

In our immunohistochemical study, 74 cases (39.1%) of OSCC showed a mostly cytoplasmic positivity for uPAR, whereas 115 were negative. uPAR expression correlated with tumour differentiation grade and prognosis: percentage of positive cases was the greatest in G3 (70.4%) and patients positives for uPAR expression had an expectation of life lower than those for uPAR negatives.

Conclusion

The results obtained in this study suggest a role of uPAR as a potential biomarker useful to identify higher risk subgroups of OSCC patients.

Survivin gene-expression and splicing isoforms in oral squamous cell carcinoma

PURPOSE

Survivin, an inhibitor of apoptosis protein and a cell cycle regulator, has been detected in the majority of human cancers. Five splice variants (survivin, survivin-2alpha, survivin-2B, survivin-3B, and survivin-DeltaEx3) have been identified; their expressions have been investigated here.

METHODS

By means of RT real-time PCR and immunohistochemistry, we have evaluated survivin isoform expressions at both mRNA and protein levels in human normal oral tissue, precancerous lesions, and oral squamous cell carcinoma (OSCC). Their correlations with the pathological findings have also been analyzed.

RESULTS

Expression levels of all survivin transcript variants were markedly elevated in OSCC when compared to normal tissues. One-way analysis of variance (ANOVA) revealed highly significant up-regulation of survivin (P = 0.001), survivin-DeltaEx3 (P = 0.001) and survivin-2B (P = 0.004), whereas survivin-3B showed a minor increase in OSCC compared to normal mucosa.

CONCLUSIONS

Our findings suggest that survivin isoforms deregulation may have significant implications in tumor aggressiveness and prognosis.

Oral mucosal diseases: Mucous membrane pemphigoid

Subepithelial vesiculobullous conditions are chronic autoimmune disorders that arise from reactions directed against components of the hemidesmosomes or basement membrane zones (BMZ) of stratified squamous epithelium to which the term immune-mediated subepithelial blistering diseases (IMSEBD) has been given. Mucous membrane pemphigoid (MMP) is the most common, but variants do exist. Non-immune disorders that involve these epithelial components typically have a genetic basis--the main example being epidermolysis bullosa. All subepithelial vesiculobullous disorders present as blisters and erosions, and diagnosis must be confirmed by biopsy examination with immunostaining, sometimes supplemented by other investigations. No single treatment reliably controls all subepithelial vesiculobullous disorders; the immunological differences within IMSEBD may account for differences in responses to treatment. Currently, as well as improving oral hygiene, immunomodulatory treatment is used to control the oral lesions of MMP, but it is not known if its specific subsets reliably respond to different agents.

MMP-13 (collagenase 3) localization in human temporomandibular joint discs with internal derangement

The normal articular disc of the human temporomandibular joint (TMJ) consists of regularly arranged collagen fibers and fibroblast-like cells. Disc tissue is subjected to various types of loading. Adaptive remodelling entails microscopic changes in which different types of collagen and non-collagen proteins, as well as matrix metalloproteinases (MMPs), are involved. Collagenase-3 (MMP-13) seems to play a key role. The aim of the study was to evaluate its involvement in TMJ disc histopathology. We studied 10 discs from patients with arthropathy of the TMJ. Paraffin wax-embedded sections were processed for histological and immunohistochemical analysis. A well-characterized mouse monoclonal anti-MMP-13 antibody (anti-collagenase 3) was used. The results showed increased MMP-13 immunoreactivity in TMJ diseased disc tissue was correlated with the severity of the histopathological changes. The more severe the pathological changes, the greater the number of immunolabelled cells detected. Nearly all chondrocyte-like cells were immunopositive, whereas fibroblast-like cells and fibrochondrocytes were more rarely labelled. MMP-13 upregulation in disc tissue from patients with TMJ internal derangement suggests that MMP-13 is involved in disc histopathology, and that disc cells actively participate in the synthesis of extracellular matrix-degrading proteinases.

Oral manifestations in patients with gastro-oesophageal reflux disease: a single-center case-control study

OBJECTIVE

To assess the occurrence of oral pathological changes and symptoms in patients affected by gastro-oesophageal reflux disease (GERD).

PATIENTS AND METHODS

200 patients with GERD and 100 matched healthy controls were studied. Thorough visual examination of the dental and oral mucosal tissues was performed and medical history relevant to oral symptoms was collected. The primary outcome was defined as a statistically significant difference, between the study group and controls, in the presence of the following indicators: soft/hard palate and uvula erythema, tooth wear, xerostomia, oral acid/burning sensation, subjective halitosis and dental sensitivity. Statistical analysis included chi-squared test, and crude odds ratio with 95% CI.

RESULTS

Univariate analysis showed that xerostomia, oral acid/burning sensation, subjective halitosis, and soft and hard palate mucosa and uvula erythema were more common in patients with GERD than matched controls (P < 0.05).

CONCLUSIONS

This study failed to find any significant association between GERD and dental erosions, whereas some symptoms and other objective oral mucosal changes were found to be significantly associated with GERD.

Zirconium oxide regulates RNA interfering of osteoblast-like cells

Zirconium oxide (ZO) has outstanding mechanical properties, high biocompatibility and high resistance to scratching. Since dental implants are made with ZO and the genetic effects of ZO on osteoblasts are incompletely understood, we used microRNA microarray techniques to investigate the translation process in osteoblasts exposed to ZO. By using miRNA microarrays containing 329 probes designed from Human miRNA sequences, we identified in osteoblast-like cells line (MG-63) cultured on ZO disks several miRNA whose expression was significantly modified. The most notable regulated genes acting on osteoblasts are: NOG, SHOX, IGF1, BMP1 and FGFR1. The data reported below represent the first study on translation regulation in osteoblasts exposed to zirconium and one in which the effect of ZO on bone formation has been detected.

Calcium sulfate acts on the miRNA of MG63E osteoblast-like cells

Calcium sulfate (CaS) is a highly biocompatible material and enhances bone formation in vivo. However, how CaS alters osteoblast activity to promote bone formation is incompletely understood. We therefore investigated the translation regulation in osteoblasts exposed to CaS by using microRNA microarray techniques. Transduction, transcription, and translation are the three levels of regulation of cell activity. Recently, a new type of translation regulation has been identified: RNA interference (RNAi). RNAi is a process in which microRNA, (miRNA), that is, noncoding RNAs of 19-23 nucleotides can induce sequence-specific mRNA degradation and/or translational repression. The human genome encodes a few hundred miRNAs that can post-transcriptionally repress thousands of genes. The miRNA oligonucleotide microarray provides a novel method of carrying out genome-wide miRNA profiling in human samples. By using miRNA microarrays containing 329 probes designed from Human miRNA sequences, we identified in osteoblast-like cells line (MG-63) cultured with CaS (Surgiplaster, Classimplant, Roma, Italy) several miRNA whose expression is significantly modified. The data reported are, to our knowledge, the first study on translation regulation in osteoblasts exposed to CaS. They could be relevant to a better understanding of the molecular mechanism of bone regeneration and as a model for comparing other materials with similar clinical effects.

Short-period effects of zirconia and titanium on osteoblast microRNAs

BACKGROUND

MicroRNAs (miRNAs) are a class of small, functional, noncoding RNAs of 19 to 23 nucleotides which induce degradation of specific messenger RNAs (mRNAs), thus controlling the translational process (ie, synthesis of proteins from mRNAs). In addition, mRNAs regulate the promoter of specific miRNAs activating an autoregulatory feedback loop.

PURPOSE

Titanium and zirconium dioxide ceramics (ZDCs) are used to make dental implants. Because the molecular mechanism by which ZDC and Ti act on osteoblasts is incompletely understood, we attempted to get more information by comparing the effect of ZDC and Ti on osteoblast miRNAs.

MATERIALS AND METHODS

By using miRNA microarray technique, we identified in osteoblast-like cell line (MG63) grown on grade 3 Ti and ZDC disks several miRNAs whose expression was modified. We collected mRNAs after 24 hours of cell culturing to better understand molecular events related to early bone healing around inserted implants. An mRNA microarray technique was then performed as a control.

RESULTS

There were six up- and four down-regulated miRNAs. Because every miRNA regulates hundreds of genes, we focused only on those related to bone formation. Among them, the most notable are BMP4 and 7, which are both up-regulated in osteoblasts cultured on Ti disks.

CONCLUSION

The detected miRNAs differentially expressed in osteoblast-like cells grown on ZDC versus Ti act on a limited number of miRNAs and bone-related genes. The most notable are BMP4 and 7, which are more expressed in osteoblasts exposed to Ti surface. Consequently, we suggest that Ti surfaces could provide some advantages to immediate load implantology.

Bisphosphonate-associated osteonecrosis can hide jaw metastases

BACKGROUND

Osteonecrosis of the jaw is a well known potential complication of bisphosphonate treatment but its pathogenesis is poorly understood. The current management of patients with bisphosphonate-associated osteonecrosis (BON) is based on "expert recommendations" and there is a recognized need of better evidence. We report two cases where BON hid jaw metastases and use them to discuss some limitations of the current recommendations.

PATIENTS

Two patients undergoing long-term I.V. amino-bisphosphonate treatment for metastatic cancer presented with areas of intraorally exposed jawbone. Bisphosphonate-associated osteonecrosis was diagnosed on the basis of medical history, clinical and radiological features. They underwent surgical resection of the affected jaw due to unrelenting pain and lack of response to conservative treatments.

RESULTS

Histological examination of the surgical specimen revealed cancer cells at the margins of the site of osteonecrosis. Our patients did not undergo bone biopsy according to current recommendations, due to lack of clinical and radiological signs suggestive of jaw metastases.

CONCLUSIONS

Our findings show that: i) patients with BON may also have jaw metastases; ii) there may not be clinical or imaging hints to this fact and; iii) that a biopsy based on careful selection of the site (with inclusion of necrotic margins) may be needed to reach the correct diagnosis. Further studies should be performed on this topic because of its very important prognostic implications.

Solitary fibrous tumor of the oral cavity: the need for an extensive sampling for a correct diagnosis

BACKGROUND

Solitary fibrous tumor (SFT) is an uncommon but well-characterized soft tissue tumor that was first described as a pleural lesion and now is considered ubiquitous, having been detected at many extra-pleural sites (abdominal cavity, orbit, upper respiratory tract, and oral cavity). Histologically, SFT may show wide morphological variability of both its cellular and stromal components, which may lead to incorrect diagnosis especially when dealing with small incisional biopsies.

MATERIALS

We report on the clinical, morphological and immunohistochemical features of eight SFT occurring in the oral cavity.

RESULTS

Microscopically all eight tumors showed widely variable morphological features in terms of cellular density and stromal architecture, thus simulating benign fibrous histiocytoma, schwannoma, hemangiopericytoma or low-grade sarcoma in distinct areas of the same lesion. Among these eight cases, five had been diagnosed as SFT, two as benign fibrous histiocytoma and one as low-grade sarcoma.

CONCLUSIONS

In consideration of the heterogeneous morphological appearance of SFT, inaccurate sampling of the mass may lead to misdiagnosis and inappropriate treatment. Therefore, an accurate histological examination of multiple tissue sections is advised, along with the use of appropriate immunostains.

Nicotinamide N-methyltransferase upregulation inversely correlates with lymph node metastasis in oral squamous cell carcinoma

We investigated expression levels of Nicotinamide N-Methyltransferase (NNMT), an enzyme involved in the biotransformation of many drugs and xenobiotic compounds, in oral squamous cell carcinoma (OSCC). Measurements were performed by semi-quantitative RT-PCR and quantitative real-time PCR in tumor and matched adjacent healthy tissue. Interestingly, NNMT was up-regulated in most of the favorable OSCCs, while no marked NNMT expression alterations between tumor and normal mucosa were detected in most of the unfavorable OSCCs. Western blot and immunohistochemical analyses also were performed and the relationship between tumor characteristics and NNMT levels in OSCC were studied to evaluate the effectiveness of NNMT as a prognostic marker in the squamous cell carcinoma of the oral cavity. In summary, the present study suggests that NNMT may have potential as a biomarker and a therapeutic target for OSCC.